Field Evaluation of HCl CEMS at Holcim St. Genevieve Plant

December 19, 2012

Prepared by:

Jim Peeler Emission Monitoring Inc.

Glen Rosenhamer Holcim Inc.

Executive Summary

Holcim (US) Inc. developed, planned and executed a field evaluation project of four HCl CEMS at the St. Genevieve plant during the summer and fall of 2012. The study was conducted to identify continuous emission monitoring systems (CEMS) that may be capable of reliable operation and able to provide accurate and precise HCl monitoring data at a contemporary preheater precalciner kiln system and to provide information regarding appropriate performance specifications and technical requirements for such CEMS. The information gained from the study will assist Holcim plants in the US in deciding how best to demonstrate continuous compliance with new strict HCl emission limits and to determine which HCl measurement systems are best suited to Holcim’s needs regarding continuous monitoring of HCl and other emission parameters. It is hoped that the substantial technical results and information gained from the study will be of use to the United States Environmental Protection Agency (EPA) in its current efforts to develop HCl CEMS performance specifications and quality assurance requirements.

Various technologies and numerous monitoring systems were considered during the selection process which considered many factors. Holcim selected the two extractive Fourier Transform Infrared (FTIR) based CEMS that were judged most likely to be successful during the project timeframe for measuring both HCl and other emission parameters. Holcim also selected a cross stack in-situ tunable diode laser (TDL) monitor for HCl only measurements which was judged to be the furthest along a development path that may result in a monitor that is acceptable under developing EPA requirements. A SICK MCS100E (extractive multi-parameter non-dispersive infrared CEMS) permanently installed and used at the St. Genevieve plant for monitoring of SO2, NOx, CO, CO2, and other parameters for regulatory purposes, was also evaluated during the project.

The initial project schedule required equipment suppliers to complete installation and insure the CEMS were fully operational by July 15. However, numerous issues were encountered, significant trouble shooting efforts continued, and significant revisions and modifications continued for two additional months for both of the extractive FTIR CEMS directly related to the measurement of HCl. Modification to the TDL CEMS were also made during the project to address the effects of effluent temperature changes with raw mill operation. Changes to the TDL quantification method were made during the test week. The three new CEMS evaluated during this project need further development and refinement before they can be considered viable commercially available CEMS suitable for monitoring HCl emissions at cement plants.

Draft EPA HCl CEMS technical requirements are still in the early stages of development, not yet based on actual laboratory or field test results, and are likely to change as more information becomes available, and through the rulemaking process. Therefore, while the performance of

the HCl CEMS included in this project can be judged relative to scientific principles, good engineering practices for monitoring air pollutants, candidate technical specifications, and HCl reference measurements, it is not possible to determine whether the CEMS will be able to meet EPA’s final requirements. In fact, many of the results acquired during this project suggest that EPA’s current draft performance specifications will need substantial revision.

The Thermo Scientific OMNI FTIR CEMS evaluated was a Pilot/Beta unit and has not been released for sale to commercial clients. Nevertheless, this was the only extractive CEMS in the study that had the capability to perform dynamic spikes, manually, remotely and by an automated procedure. It was the only extractive CEMS that demonstrated proper responses to dynamic spikes over a wide range of conditions, demonstrated acceptable zero and upscale calibration drift for both criteria pollutants and HCl, passed relative accuracy tests over a wide range of concentrations, and was capable of measuring very low HCl concentrations (<0.22 ppm) introduced at the sample probe.

The CEMTEK TDL CEMS was the simplest system to install and start-up and required virtually no maintenance attention. The TDL CEMS passed the RATA at all test conditions and HCl concentrations. The results of numerous dynamic spikes performed using the flow-through cell optically in-line with the effluent measurement path demonstrated the accuracy and precision of the TDL data and the ability of this spiking approach to be used as a quality assessment procedure. The TDL system was shown to be capable of HCl concentration measurements less than 0.16 ppm for the St. Genevieve installation.

The compressed gas HCl mixtures were a source of significant confusion and frustration during the three months of field work and a disappointment relative to expectations. The HCl calibration gas certified values do not accurately reflect the values of these gas mixtures as determined by the on-site reference FTIR re-analysis and confirmed by three other independent measurement systems. Discrepancies between the certified analysis and re-analysis values of 12-70% for most cylinders, with only four out of 25 certified values accurate within 10% error. It is concluded that the dry gas calibration mixtures in the range of 5 to 100 ppm HCl cannot be considered “standards”, cannot be used to establish monitor calibrations, and cannot be used for assessing the accuracy of CEMS based on assigned tag values, which, happens to be the main basis for the current draft EPA HCl Performance Specification.

The compressed gas mixtures can be used for dynamic spike assessments where the cylinder value is assigned by direct analysis of the spike gas in the field, immediately prior to the test, or, for use in short term drift tests.

Valid dynamic spike procedures can be implemented for FTIR-based CEMS using either SF6 or N2O as a tracer gas to quantify the spike rate. This provides flexibility for equipment suppliers

to choose the method most appropriate for their measurement system. Properly conducted dynamic spikes introduced upstream of all active sampling components will detect sample condensation, reaction, or adsorption losses in the sample transport equipment. This capability is critically important for cement kiln applications where HCl and ammonia are both present and formation of ammonium chloride salts poses a significant challenge for extractive systems, especially where effluent temperatures and concentrations change with raw mill operating conditions.

Limitation of detection (LOD) tests results from laboratory tests or TÜV certifications based on “noise limited calculations” have little to do with the actual performance of any installed CEMS and ignore important issues such as measurement bias and analytical interference which are limiting factors to low concentration measurements. In contrast, limitation of system tests (LOS), as defined in this study, can be conducted in the field and be performed to demonstrate the ability of both extractive and certain in-situ CEMS to actually measure HCl at very low concentrations under representative and challenging operating conditions.

Relative accuracy test specifications should include an absolute mean difference tolerance which accounts for the LOD and LOS of the reference measurement system and its sensitivity. The mean difference specification must be set much higher than the LOD, and should be set considering the practical quantification limit of the reference system. The use of a traditional relative accuracy tests should not be required for HCl CEMS, whereas, performing dynamic spikes can demonstrate acceptable measurement accuracy.

Further technical investigations are needed to address important technical issues regarding the establishment of “zero” for FTIR-based CEMS. These include questions regarding (a) whether the background spectrum is acquired from zero gas conveyed directly to the optical measurement cell, or through the probe, particulate filter and sampling system, (b) subtraction of apparent zero gas system responses, (c) treatment of spectral residuals, (d) averaging of apparent negative measurement values, and (e) reporting of measurements where some or all measurement data within an averaging period is below the LOD or LOS.

Development and demonstration efforts by all of the CEMS equipment suppliers that were included in this Holcim field project are on-going. Two of the participating suppliers implemented additional modifications to the CEMS at the St. Genevieve plant and acquired additional test results after the evaluations described in this report were completed. One supplier acquired additional test results after the period of this report and has prepared a separate addendum report with additional information. Additional tests at the St. Genevieve plant using a new Beta FTIR during the third quarter of 2013 are under consideration. The other two suppliers are actively involved in other field studies and evaluations. Technical refinements and new developments are expected to continue in this rapidly evolving field.

FORWARD

The authors have attempted to prepare this report in a manner that accurately and completely reflects the events, conditions, evaluation procedures, data, results and findings of the project. Data reduction, calculations, and other determinations have been checked as thoroughly as possible within the time and resource constraints of this project. Preliminary results and draft reports have been subject to internal review and to review by equipment suppliers participating in this study on several occasions to detect errors or mistakes, to provide opportunities for input, and to afford opportunities to identify proprietary information. Nevertheless, these efforts and considerations are balanced with the necessity to complete the report so that the information can be used in a timely fashion due to current and on-going technical and regulatory developments. If errors or other technical issues are discovered by reviewers of this information, we request that these issues be directed to the attention of the authors.

Contents

1. Introduction 1 2. Objectives and Project Approach 3 3. Summary of Results 5 4. Conclusions 10 5. Project Overview & Chronology 14

5.1. Selection of Equipment Suppliers 14 5.2. May 1 Plant Visit 16 5.3. Calibration Gases 17 5.4. Meeting with EPA at RTP NC 18 5.5. Monitor Installation and Start-up 18 5.6. Site Visit Shakedown July 25-26 19 5.7. July 26 –Aug 10 20 5.8. Aug 10 - Test Postponed 20 5.9. Aug 13-September 16 - Further CEMS Development Efforts 20 5.10. Test Week Chronology 22 5.11. EPA Site Visit September 25 24 5.12. Second Meeting with EPA at RTP NC 24 5.13. November 19 Draft Project Report 24 5.14. December 19 Project Report 24

6. Test Procedures 25 6.1. Stratification Test Procedures 25 6.2. RATA Test Procedures 27 6.3. Dynamic Spike Test Procedures 28 6.4. Limitation of Detection (LOD) and Limitation of System (LOS) Test Procedures 31

7. Thermo Scientific OMNI FTIR Results CEMS Results and Observations 33 7.1. Description 33 7.2. Installation and Start-Up 33 7.3. RATA Tests 34 7.4. Dynamic Spikes 41 7.5. Compressed Gas Cylinder Analysis 47 7.6. Zero and Upscale Calibration Checks and Drift Tests 48 7.7. Limitation of Detection (LOD) and Limitation of System (LOS) 49

8. ABB ACF-NT CEMS Results and Observations 56 8.1. Description 56 8.2. Installation and Start-Up 56 8.3. RATA Tests 57 8.4. Dynamic Spikes 64

8.5. Compressed Gas Cylinder Analysis 67 8.6. Zero and Upscale Calibration Checks and Drift Tests 71 8.7. Limitation of Detection (LOD) and Limitation of System (LOS) 71

9. CEMTEK/Unisearch TDL Results and Observations 73 9.1. Description 73 9.2. Installation and Start-Up 74 9.3. RATA Tests 74 9.4. Dynamic Spikes 78 9.5. Limitation of Detection (LOD) and Limitation of System (LOS) 85 9.6. Appendix 9A -CEMTEK correspondence (not numbered)

10. SICK MCS100E Results and Observations 87 10.1. Description 87 10.2. MCS100E Status 87 10.3. RATA Tests 88 10.4. Dynamic Spikes 89 10.5. Compressed Gas Cylinder Analysis 98 10.6. Limitation of Detection (LOD) and Limitation of System (LOS) 98

11. HCl Calibration Gas Re-Analysis 101

Appendix 1 - Project Scope

Appendix 2 - Prism Analytical Technology Inc. Test Report (separate volume)

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Field Evaluation of HCl CEMS at Holcim St. Genevieve Plant

1. Introduction Holcim (US) Inc. (Holcim) developed, planned and executed a field evaluation project of four HCl CEMS at its St. Genevieve plant during the summer and fall of 2012. In broad terms, the study was conducted to determine if contemporary HCl continuous emission monitoring systems (CEMS) have the capability, accuracy, precision and reliability to allow Holcim plants in the US to demonstrate continuous compliance with new strict HCl emission limits and to determine which HCl measurement systems are best suited to Holcim’s needs regarding continuous monitoring of HCl and other emission parameters. Section 2 of this report explains the objectives of the study and the approach that was implemented. Section 3 presents the summary of results. Section 4 presents conclusions derived from this project. Section 5 describes the selection of the study participants, and provides a chronology of the measurement systems deployment over several months. Section 6 describes the test procedures used for a stratification test, relative accuracy test audits (RATAs) at multiple conditions, dynamic spikes (also referred to as “analyte spikes”) and limitation of detection and limitation of system determinations. Sections 7 through 10 detail monitor-specific test results for the performance tests conducted during September 2012 for each of the CEMS. Section 11 presents the re-analysis results of the HCl calibration standards provided by several gas vendors for this project. All of the HCl CEMS continued to operate at the St. Genevieve plant, for one to two months, after the test week was completed to allow equipment suppliers to make improvements and changes to their systems and assess the reliability and performance over a longer period. Significant changes to the ABB CEMS were implemented and additional tests were performed by ABB and CEMSI during October and into November. Information from these efforts are included in separate addendum report. The specific objectives of the study are detailed later but were necessary because of the nature of the rapidly evolving field. The objectives cover a wide range of issues because the applicable technical requirements for the initial certification and on-going QA of the HCl CEMS were under investigation and development by EPA concurrent with the field study in advance of their formal proposal by EPA. Similarly, instrumentation suppliers were developing and significantly revising their measurement systems and approaches, and gaining initial experience in deploying these systems to meet the difficult HCl

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measurement challenges encountered at cement plants. The quality and traceability of fundamental calibration standards has not been established despite claims by compressed gas vendors, and is now certainly further questioned. However, it is important to understand that this study was conducted in view of the promulgated EPA regulations at 40CFR63, Subpart LLL which require installation, certification, operation and ongoing quality assurance of HCl CEMS to demonstrate continuous compliance with a 3 ppm HCl corrected to 7% O2, dry basis emission limit on a 30-day rolling average by not later than September 2013. Even though EPA proposed a two year extension to the deadlines in Subpart LLL several months after the Holcim study began, the promulgated regulations remain as the enforceable requirement. Holcim also seeks to provide credible technical information based on actual field testing experience at a cement plant for EPA’s consideration prior to EPA’s formal proposal of HCl CEMS performance specifications and quality assurance procedures. The study was conducted at the St. Genevieve plant under the direction of Glen Rosenhamer, Corporate Environmental Manager. Michelle Ferguson, Plant Environmental Manager, Aaron Dwyer (Electrical Superintendent), Rodney Miller (Instrumentation Specialist) provided extensive support for the project over many months. Jim Peeler, Emission Monitoring Inc. (EMI) provided consulting assistance during the entire project, participated in the field test, and prepared this report. Phil Kauppi, Prism Analytical Technologies, Inc. performed the FTIR testing for the stratification test, the Method 321 tests for the RATAs, and analyzed numerous compressed gas cylinders. CEMS evaluated were:

A. Thermo Scientific OMNI FTIR CEMS (direct extractive wet basis measurement) B. ABB ACF-NT FTIR CEMS (direct extractive wet basis measurement) C. CEMTEK/Unisearch TDL (cross-stack in-situ wet basis measurement) D. SICK MCS100E (direct extractive IR multi-parameter hot wet measurement

system: reporting results on a dry basis)

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2. Objectives and Project Approach The objectives are stated in the Project Scope document that was developed and distributed to participants at the beginning of the study. They are:

2.1. . Obtain actual on-site data to assist in the development, support and defense of an HCl Performance Specification appropriate and achievable for the cement industry.

2.1.1. Determine accuracy of vendor supplied cylinder gases at concentration necessary to meet anticipated performance specifications.

2.1.2. Determine viability of analyte spiking methodologies to establish performance specification requirements.

2.1.3. Determine realistic detection limits using commercially available equipment installed at a cement manufacturing facility.

2.1.4. Perform a conventional RATA, via third party, on multiple analyzers to determine which instruments are best suited to meet upcoming HCl standard requirements.

2.2. Determine what technologies and equipment supplier(s) are best suited to meet future multi-component monitoring requirements.

2.2.1. Identify viable equipment for future monitoring requirements. 2.2.2. Identify a complete measurement system capable of measuring HCl at relevant

detection limits 2.2.3. Determine what company provides the best overall CEMs solution to current and

future facility monitoring needs.

The Holcim St. Genevieve (GV) plant is a contemporary preheater precalciner kiln system which began operation during 2009. The kiln system has two inline raw mills and operating conditions include: (a) both raw mills operating, (b) one raw mill operating, and (c) no raw mills operating. These operating conditions affect the associated effluent HCl concentrations, the concentrations of other effluent components including NH3, as well as the effluent gas temperatures. HCl effluent concentrations varied over a range of 0-20 ppm, wet basis. Effluent gas temperatures also vary with operating condition and were expected to be approximately 205°F (two mills on), 255°F (one mill on) and 320°F (no mills operating).

The project approach was based on selecting the two FTIR based CEMS that were judged most likely to be successful during the project timeframe for measuring both HCl and other emission parameters and another non-FTIR technology for HCl only measurements. These instruments were to be installed during June and early July, be fully functional by July 15 and be shown to be able to meet certain performance specifications and quality assurance requirements performed by the supplier’s representatives including: limitation of detection tests, calibration error/linearity tests, analyte spiking tests, and a seven-day zero and upscale calibration drift

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test. Independent performance tests including dynamic spiking and relative accuracy test comparisons with Method 321 results were planned for mid-August. Significant problems were encountered with most of the new measurement systems. Plant operations also delayed the performance test until mid-September due to market conditions. Many expected test results noted above were not completed prior to testing, even with, the 30-day testing delay due to the multiple complexities and discovered short-comings when analyzing HCl emissions continuously at a cement plant. For this project, all performance assessments including relative accuracy were made on wet basis HCl concentration. No effort was made to correct data to units of the Subpart LLL standard (ppm HCl corrected to 7% O2 dry basis).

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3. Summary of Results The project schedule required that equipment suppliers complete installation of the CEMS and insure the systems are fully operational by July 15. Numerous issues were encountered, significant trouble shooting efforts continued, and significant revisions and modifications continued for two additional months for both of the extractive FTIR CEMS. Final changes to the two FTIR CEMS were made on the weekend preceding the test week. Modifications to the TDL CEMS were also made prior to the rescheduled Sept. 17 test week, and changes to the TDL quantification method and calculations were made during and after the test week. The relative accuracy test audit (RATA) results over a wide range of effluent concentrations are summarized for each CEMS. Details and multiple calculations are provided in each monitor-specific section.

Thermo Scientific OMNI FTIR CEMS – RATA Results for Raw Data HCl Concentration Range ≤ 20% Of Ref Value ≤ 10% Of Emission

Standard High 4.0-15.0 ppm Pass Mid 0.7-3.0 ppm Fail Fail

Low <0.3 ppm Pass

Thermo Scientific OMNI FTIR CEMS – RATA Results for Zero Corrected Data HCl Concentration Range ≤ 20% Of Ref Value ≤ 10% Of Emission

Standard High 4.0-15.0 ppm Pass Mid 0.7-3.0 ppm Pass (9 runs) Pass (9 runs)

Low <0.3 ppm Pass

ABB FTIR CEMS – RATA Results HCl Concentration Range ≤ 20% Of Ref Value ≤ 10% Of Emission

Standard High 4.0-15.0 ppm Fail (Pass with Prism probe) Mid 0.7-3.0 ppm Fail (Fail with Prism probe) Fail (Fail with Prism probe)

Low <0.3 ppm Fail

CEMTEK TDL CEMS – RATA Results HCl Concentration Range ≤ 20% Of Ref Value ≤ 10% Of Emission

Standard High 4.0-15.0 ppm Pass Mid 0.7-3.0 ppm Pass

Low <0.3 ppm Pass

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SICK MCS100E CEMS – RATA Results HCl Concentration Range ≤ 20% Of Ref Value ≤ 10% Of Emission

Standard High 4.0-15.0 ppm Pass Mid 0.7-3.0 ppm Fail Fail

Low <0.3 ppm Fail HCl calibration gases were provided by AirGas and Linde at 5 and 10 ppm concentrations for routine calibration checks, and at 25 and 100 ppm for dynamic spikes. One 300 ppm level gas was used for spikes of the flow through calibration cell for the in-situ TDL CEMS. Concerns were expressed by the CEMS providers throughout the start-up and troubleshooting period regarding the accuracy of the HCl cylinder tag values. Re-analysis of 25 HCl cylinders by Prism using the reference FTIR revealed gross discrepancies between the HCl cylinder tag values and the FTIR analysis results. Measured errors ranged from from 12% to 70% of the tag value for 21 of 25 cylinders that were reanalyzed. Only two cylinders had a deviation of less than 5% from the tag value, and both of these were nominal 25 ppm HCl cylinders which were certified only three days prior to the on-site reanalysis by Prism. Only two other cylinders (another 25 ppm and a 318.5 ppm cylinder gas) had a deviation of less than 10% from the tag value. The nominal 10 and 5 ppm HCl gases exhibited even greater deviations from the tag value. Excluding gases that had been certified only three days prior to Prism’s field reanalysis, revealed differences from the certified concentration ranging from 21% to 48% for the nominal 10 ppm gases, and 25% to 75% for the nominal 5 ppm gases. In every one of the 25 HCl cylinders reanalyzed in the field, it was found that the measured value was lower than the certified value. Furthermore, comparison of HCl cylinder gas analyses by the Thermo Scientific OMNI FTIR, the ABB ACF-NT FTIR and the SICK MCS100E all agreed closely with the Prism analysis results. The fundamental calibration of these four independent measurement systems are established in completely different ways and are verified by comparison to other reliable standards. There are indications that the HCl concentrations are degrading over time. However, there is insufficient information to discern whether the HCl compressed gas mixtures degrade over time, cannot be quantitatively recovered from the cylinder, or were incorrectly analyzed and labeled by the suppliers, or that some combination of these issues are present. The injection of dry HCl calibration gases into an extractive HCl CEMS system, including the probe, sample line, and monitoring system, requires a period of 15 to 25 minutes to achieve a reasonably stable response (98-99%). A more stable response was achieved

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after a longer period of 30-45 minutes. One equipment vendor indicated it would take many hours to fully stabilize a dry HCl calibration gas. However, indications obtained during the test did not support this statement. The response time depends on many monitor-specific factors including length of calibration and sample line, diameter of calibration and sample line, temperature, sampling rate, HCl concentration, etc. The appropriate period to inject the gas may also depend on the purpose. A shorter time is necessary for a check or verification of monitor status with a reasonable tolerance, and where adjustment or “calibration” of the monitor is not intended. The time required for HCl dry gas calibrations, and time required for the measurement system to recover, including the period of invalid elevated HCl concentrations that must be discarded when wet effluent gas is reintroduced to the measurement system, could prohibit many CEMS from achieving acceptable data availability. The Thermo Scientific OMNI FTIR CEMS was the only extractive CEMS successfully challenged with HCl calibration gases as well as SO2/NO/CO calibration gases that was able to complete a seven day calibration drift test during this project. The OMNI FTIR CEMS can meet the criteria pollutant and diluent monitor zero and upscale drift test requirements such as those found in 40CFR60, Appendix B, Performance specification 2, 3, and 4. The OMNI FTIR CEMS was demonstrated to achieve a HCl zero drift limit of ± 0.25 ppm and an HCl upscale drift limit of ± 0.50 ppm based on uncorrected values for a short term test. The test results demonstrate that dynamic spikes (analyte spikes) can be used to assess the accuracy of extractive CEMS HCl measurement accuracy using the direct analysis of the cylinder gas value in spike recovery calculations, during periods of operation with stable HCl emissions that result in the HCl component of the spike concentration representing a minimum of 10% of the stack emission level. The spike recovery calculations for the ABB FTIR CEMS demonstrate that both SF6 and N2O tracers in the calibration gases at appropriate concentrations can provide equivalent indications of spike recoveries. Thermo CEMS results demonstrate that dynamic spike results can be acquired over a wide range of conditions by manual spikes performed by the operator and by an automated procedure which runs without an attendant. ABB FTIR CEMS demonstrated that dynamic spikes could be performed manually using external equipment to control spike gas flow rate. It was particularly noteworthy that spikes introduced downstream of a cold spot in the ABB sample probe did not detect a malfunctioning system, as should be expected.

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The dynamic spike procedure for the SICK MKS100E CEMS was cumbersome and difficult to implement, but other approaches were limited by the fact that this CEMS is used for the plant compliance monitoring requirements and could not be modified. Nevertheless it showed that the CEMS was capable of accurate measurements concentrations above 10 ppm. The procedure must be repeated several times to minimize imprecision in the spike results. The external spike method which determines the spike rate based on the reduction of other measurement compounds is not appropriate for spike injection rates less than 10% of the sample flow rate. The dynamic spike procedures for the TDL CEMS were easy to perform and could be done quickly because of the rapid response time of the measurement system. Initial dynamic spikes that indicated varying responses proved to be an effective tool to identify a problem with the monitor optical alignment which was then simply and quickly resolved. The subsequent dynamic spike recoveries for the TDL typically ranged from 102% to 115% over a wide range of effluent concentrations. Replicate spikes over short periods produced very consistent spike recoveries varying 1% or less (e.g., 105% to 106%). An unambiguous explanation about how the site-specific fundamental calibration of the TDL was established has been provided by CEMTEK/Unisearch. Certain issues about the potential effects of CO2 broadening related to calibration gases used for spikes and calculation of associated spike recoveries are still being investigated. Limitation of detection tests performed for representative analyzers under laboratory conditions have minimal application to real world conditions and the significant effects of the sampling system after measurement of cement kiln effluent. It is absolutely apparent from the field test results that the background concentrations seen by an analyzer through the sampling system are strongly affected by the recent use of the system to quantify calibration gases and measure effluent samples, and that these effects are dependent on the changing conditions in the kiln exhaust stack. The noise limited detection limit of an analyzer without HCl present is of little practical use, or overall merit in any field application specification, standard, or quality assessment. Limitation of system measurements performed by successively decreasing analyte spikes were performed in the field for the Thermo Scientific OMNI FTIR CEMS and demonstrated conclusively that the system was able to quantitatively transport ≤0.22 ppm HCl introduced into the actual effluent sample matrix upstream of the particulate filter, through the filter and sample lines to the heated analyzer cell, and reliable sense the increase in concentration and display the measurement response.

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Similarly, dynamic spikes of HCl calibration gas in the TDL flow through calibration gas cell were able to demonstrate that the monitor could sense an incremental change equivalent to ≤0.16 ppm HCl in the presence of very low effluent HCl concentrations. Although both the ABB ACF-NT FTIR CEMS and the SICK MCS100 CEMS report low laboratory determined LODs in their respective TÜV certifications, neither of these systems was able to provide accurate low concentration measurements. Two potential reasons for this inability include possible analytical interferences or inappropriate cross component compensation Based on further investigation after the test project, it is believed that a majority of the analytical interference for the ABB ACF-NT FTIR CEMS has been identified. Detection or quantification of spatial variation in HCl concentration by performing an HCl “stratification test traverse” cannot be accomplished when effluent concentrations are at or near the LOD of the measurement system. In most monitoring applications there is no scientific or engineering justification to suggest any possibility of HCl stratification at a monitoring location. A simple test can be used to detect the presence of stratification due to air in-leakage.

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4. Conclusions

Although this project attempted to select CEMS that were the most mature, and believed most likely to be able to meet applicable performance specifications and quality assurance requirements, none of these systems can be considered commercially available and able to meet all of the applicable QA criteria at the time this study was performed.

The time period and extensive activities that were performed during the installation, start-up and troubleshooting over more than two months for the FTIR-based CEMS do not reflect robust, reliable, or mature fully developed measurement systems suitable for deployment at cement plants.

Two extractive CEMS evaluated which are known to be widely used for monitoring of SO2, NO, CO, and CO2 emissions at cement plants for many years did not demonstrate acceptable performance during the period of this field study for measurement of HCl at the concentrations and conditions necessary to demonstrate continuous compliance with 40CFR63 Subpart LLL HCl emission standards for preheater/precalciner cement kiln systems.

In contrast, the Thermo Scientific OMNI FTIR CEMS evaluated was a Pilot/Beta unit and has not been released for sale to commercial clients. Thermo Fisher Scientific participated in the project to gain experience and revise its monitoring equipment and refine its technical procedures. Nevertheless, this was the only CEMS in the study that had the capability to perform dynamic spikes, manually, remotely and by an automated procedure. It was the only extractive CEMS that demonstrated proper responses to analyte spikes over a wide range of conditions, demonstrated acceptable zero and upscale calibration drift for both criteria pollutants and HCl, was capable of passing relative accuracy tests over a wide range of concentrations, and was capable of measuring very low HCl concentrations (<0.22 ppm) introduced at the sample probe.

The CEMTEK TDL CEMS was by far the simplest system to install and start-up and required virtually no maintenance attention during the study. The TDL CEMS passed the RATA at all test conditions and HCL concentrations. The results of numerous dynamic spikes performed by introducing high level calibration gas concentrations to the flow-through cell optically in-line with the effluent measurement path demonstrated the accuracy and precision of the TDL measurement data and the ability of this spiking approach to be used as a quality assessment procedure. The TDL system was shown to be capable of HCl concentration measurements < 0.16 ppm for the St. Genevieve installation. The method used to establish the fundamental calibration of the monitoring system requires the use of at least one known calibration standards. The method used to estimate the zero response based on the residual of the area quantification method appears to be effective.

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The HCl calibration gas certified values (i.e., “ tag values”) do not accurately reflect the values of these gas mixtures as determined by the on-site reference FTIR re-analysis and confirmed by three other independent measurement systems. Gross discrepancies (12-70% errors) between the certified analysis and re-analysis exceeding 10% error for 21 of 25 cylinders were observed. The nominal 5 ppm and 10 ppm HCl gas mixtures were the most inaccurate, reflecting disparities between 21% and 70% in comparisons between certified values and field re-analysis. The source of these errors are not known and there is insufficient information at this time to determine if the supplier’s original analysis was incorrect, or the contents have degraded, or whether regulator delivery problems play a role, or whether all of these issues play a role. Nevertheless, it is concluded that the dry gas calibration mixtures in the range of 5 to 100 ppm HCl cannot be considered “standards”, provide no credible basis for use in calibrations or monitor evaluations as “certified” and cannot be used for assessing the accuracy of CEMS or other measurement systems. Where their use is strictly limited to stability checks over short periods (i.e., one week), or are employed for dynamic spikes where “direct analysis” of the spike gas is used rather than the certified tag value for all calculations. It should be noted that the ability to implement “strictly limited stability checks” and, “direct analysis” as stated above have their own inherent procedural and implementation shortcomings requiring considerable procedural control.

The inaccuracy in HCl compressed gas tag values prohibits the use of multiple gas cylinders for performing linearity tests on any measurement system. Quantitative dilution of a single gas would likely be far more accurate, if linearity tests are needed and are technically justified. However, procedures involving dilution of high concentration compressed gas mixtures raises other concerns regarding establishing their combined uncertainty and EPA traceability.

The time necessary for injection of dry calibration gases to achieve a final stable response suitable for calibration or adjustment of a CEMS on a daily basis may prevent achievement of acceptable CEMS availability on an ongoing basis. (Many EPA Regional Office and state agency enforcement policies initiate enforcement action for data availability of less than 95% when encountered during two consecutive reporting periods. If one-hour per day is required for HCl and other criteria pollutant measurements, the maximum data availability is 95.8% before any other maintenance, QA, or corrective action is performed.)

The injection of dry calibration gases will not necessarily detect problems in the sample acquisition and transport equipment due to sample condensation, reaction, or adsorption/desorption effects.

Valid dynamic spike procedures can be implemented for FTIR-based CEMS using either SF6 or N2O as a tracer gas to quantify the spike rate. This provides flexibility for equipment suppliers to choose the method most appropriate for their measurement system.

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Properly conducted dynamic spikes introduced upstream of all active sampling components will detect sample condensation, reaction, or adsorption losses in the sample transport equipment.

The Thermo Scientific OMNI FTIR CEMS demonstrated that its automated dynamic spike procedure provides a method to check the integrity of the sampling system on a daily basis, without any need for daily HCl dry gas injections. Under conditions of rapidly changing HCl concentrations, it may be necessary to perform multiple dynamic spikes to minimize the effects of temporal changes on the spike recovery determinations.

Appropriate detailed dynamic spike procedures (including calculations) should be developed and provided by the CEMS manufacturers. It is unlikely that there is a “one size fits all approach” and prescriptive procedures in any EPA performance specification or QA procedure are likely to restrict advances in technology and monitoring equipment improvements.

Limitation of detection (LOD) tests results from laboratory tests or TÜV certifications have little to do with the actual performance of a CEMS. The recitation of these values out of context is a source of great confusion about actual CEMS performance.

Limitation of system tests (LOS) can be conducted in the field and can be performed to demonstrate the ability of both extractive and certain in-situ CEMS to actually measure HCl at very low concentrations under representative and challenging operating conditions.

HCl stratification tests do not produce quantitative results when HCl effluent concentrations are less than 1.0 ppm, due to the inability of available monitors to measure effluent level variations accurately at this concentration. Such tests should not be required at any HCl concentration unless there is a legitimate technical design reason to expect that spatial variation exists at a particular monitoring location.

Relative accuracy test specifications should include an absolute mean difference tolerance which accounts for the LOD and LOS of the reference measurement system and its sensitivity. The mean difference specification must be set much higher than the LOD, and should be set considering the practical quantification limit of the reference system. An acceptable RATA specification for HCl CEMS which reflects current limits of technology could be: RA ≤20% of the reference mean, or RA ≤10% of the emission standard, or absolute value of mean difference ≤0.5 ppm, whichever is least restrictive.

HCl CEMS RATAs should not be required for CEMS which can demonstrate acceptable measurement accuracy by performing dynamic spikes. If an HCl CEMS can meet all of the requirements of reference Method 321 including acceptable dynamic spike recoveries, than comparison to an independent reference FTIR system meeting the requirements of Method 321 is unnecessary, redundant, and without technical justification.

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Further technical investigations, and likely additional specifications, are needed to address important technical issues regarding the establishment of “zero” for FTIR-based CEMS. These include questions regarding (a) whether the background spectrum is acquired from zero gas conveyed directly to the cell, or through the probe, PM filter and sampling system, (b) subtraction of apparent zero gas system responses, (c) treatment of spectral residuals, (d) averaging of apparent negative measurement values, and (e) reporting of measurements where some or all measurement data in an averaging period is below the LOD or LOS.

Based on the findings of this study, a practical and reasonable approach for an FTIR-based CEMS would be (a) daily gas injections of a non-reactive calibration transfer standard to verify that the FTIR analyzer is performing correctly and (b) a daily dynamic HCl spike to verify the integrity of the sample transport and analysis routine. No adjustments to the measurement system or data would be applied based on the spike results. The calibration transfer standard could be NO or CO or another parameter for which gas injections are required by other regulations where a multi-parameter CEMS is used.

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5. Project Overview & Chronology Holcim decided that the project would be performed at the St. Genevieve plant. The project began in April 2012. After considering preliminary budget estimates, it was decided that the evaluation would include two FTIR based CEMS, one non-FTIR based CEMS technology and would also include evaluation of the installed SICK MCS100E that is used for compliance monitoring for other kiln emissions parameters (SO2, NOx, CO, and CO2) at the St. Genevieve plant.

5.1. Selection of Equipment Suppliers Candidate equipment suppliers for consideration were identified based on previous experience, recent public presentations at conferences and meetings, internet information, and discussions with other knowledgeable people. Information on various equipment suppliers and monitors was reviewed and a number of vendors were contacted to discuss the project and their potential participation. Holcim/EMI/supplier conference calls were held with five candidate equipment suppliers to discuss their measurement systems. Several suppliers presented information of multiple technologies or multiple measurement approaches. In order to be considered for participation the equipment supplier had to offer a complete CEMS system (sample acquisition/transport, analyzer, system controller, and data acquisition system) designed for unattended operation at a cement plant with a reasonable level of technical support from plant personnel. Suppliers that only offered an analyzer, or that offered an instrumental measurement system capable of operation for short periods or requiring a technician to operate it, were not selected. Suppliers that could not offer to install a fully integrated measurement system at St. Genevieve by July 15 were not selected. Some suppliers explained that they only had sufficient measurement systems available or sufficient resources to participate in either the EPA laboratory study or an industry field study, and at least one chose the former. Another chose to participate in the Holcim project. One company declined to offer an FTIR-based CEMS which is part of their product line but has not been deployed in the US, and preferred to offer its multi-component IR analyzer instead. Several companies had new products under development, but the schedule of the project precluded their use. Holcim’s selection also involved other considerations. For FTIR based CEMS, instrument systems that were thought to be most likely to provide data similar to FTIRs used for low concentration emission testing in accordance with EPA Method 321 were preferred. FTIRs with thermoelectrically cooled detectors were preferred over non-cooled (i.e.,

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room temperature) detectors. Instruments with greater resolution, 0.5 to 1 wavenumbers were preferred over 2, 4 or 8 wavenumber instruments. Another important factor was whether the candidate measurement system had been previously used to monitor cement kiln emissions. If not, then the fall back criteria was whether the offering supplier have experience with other measurement systems at cement plants, or any cement plant CEMS experience at all. Business considerations were also important. At the time of the selection, Holcim was under a regulatory obligation to purchase and install HCl CEMS under a looming deadline. It was expected that monitor equipment purchase orders for multiple plants and kiln systems would need to be issued by the December 2012 to meet the deadlines. Holcim’s selection also considered whether the candidate supplier had sufficient depth and resources to be able to deliver and support multiple systems. Holcim is also one of the largest cement companies in the world with approximately 100 plants. Holcim prefers to utilize similar CEMS in many countries for economies of scale and other efficiencies where possible. It was critical to complete the selection process quickly in order to keep the project on schedule. Tentative supplier selections were completed within two weeks. A Project Scope dated April 13, 2012 (See Appendix A) was prepared for the FTIR-based CEMS and for the in-situ cross-stack TDL system and was distributed to the candidate participants. The project scope detailed the project objectives, discussed the technical performance specifications and QA procedures that would be evaluated, and provided background information on the kiln system and expected effluent conditions. The scope also set forth the project schedule and list of things required of the equipment suppliers regarding both the measurement system capabilities and technical support that would be needed during the project. The scope detailed the support and project funding that the St. Genevieve plant would provide. The scope requested a response from project participants by April 25. After further conference calls with each of four companies to discuss the scope and related issues, the selection process was completed. The CEMS selected were as follows for the reasons given along with other technical considerations.

• ABB ACF-NT FTIR based CEMS with capabilities to measure HCl and numerous other effluent parameters. Holcim has approximately 50 of these CEMS worldwide (one in the United States for about 10 years) and the platform is fairly mature and well demonstrated with respect to other parameters. A new and improved version of this system was scheduled to be under TÜV evaluation

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during the fall of 2012, but could not be provided in time for the Holcim study. ABB teamed with CEM Specialties, Inc. (CEMSI) to provide much of the installation, start-up and ongoing technical support for the St. Genevieve project.

• Thermo Scientific OMNI FTIR CEMS. This was a Pilot/Beta unit but had been previously evaluated at another preheater/precalciner cement kiln system. Thermo Fisher Scientific was also known to be participating in several other HCl CEMS demonstration projects at cement kilns and electric utility boilers. Thermo Fisher Scientific obviously has resources to support development of new CEMS and deployment at many facilities.

• CEMTEK/Unisearch cross stack TDL. This teaming arrangement couples a promising technology group judged by EMI and Holcim to be further along than the other TDL suppliers we interviewed or considered, along with a veteran CEMS integrator with a great deal of experience. Although the TDL measures only HCl (rather than multiple parameters) it was considered a potentially practical add-on alternative where existing CEMS are installed and performing well for the measurement of criteria pollutants.

• The SICK MCS100E was evaluated because it was already installed at the St. Genevieve plant and was serving as the certified compliance monitoring system for other kiln system parameters. Holcim has these systems at other plants in the United States. SICK expressed confidence that the same system could meet the challenges of monitoring HCl in accordance with new EPA draft requirements and that the MCS100E would perform as well as the SICK FTIR or TDL systems.

5.2. May 1 Plant Visit A one day meeting site inspection was held at the St. Gen plant on May 1. Two representatives from ABB Frankfurt, one CEMSI representative, two Thermo Fisher Scientific representatives, and one CEMTEK representative were present along with Jim Peeler, Glen Rosenhamer, Aaron Dwyer, Michelle Ferguson, and Rodney Miller. An inspection of the monitoring location and the available CEMS shelter was performed with all present. Because there were already many installed ports with instruments in the stack, (COMS, flow monitor, SICK MCS100E, light scattering monitor) there were concerns that installing more 4 inch ports and flanges could raise structural considerations for the stack which rises more than 100 feet above the measurement location. Decisions were made to use the existing four stack testing sample ports at 90 degree intervals around the stack for the Thermo Scientific, ABB and CEMTEK monitors. It was decided that two new 2 inch reference sampling ports could be installed and used along with two existing ports for reference testing. Preliminary discussions about

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support utilities (electrical power, instrument air), routing of sample lines and umbilical lines, telecommunication access via cell phone networks, data transfer to Holcim information systems, and other issues were held. Numerous technical issues were addressed regarding the intended specifications and evaluation procedures. For the purpose of the specific technical evaluation, it was agreed that all monitoring data would be acquired digitally, and that 4-20 ma analog signals would be used only for trending general performance. This eliminates many traditional concerns about setting measurement ranges and scaling outputs which are relics of past eras. Based on historical information, HCl emissions were expected to range between 10 and 20 ppm for two raw mills off with possible transients approaching 30 ppm. All CEMS were expected to be configured to measure at least 0-30 ppm HCl, and/or higher levels, if this could be done without loss in resolution or data quality. Based on the Project Scope and the May 1 meeting, it was agreed that all CEMS should be installed and fully operational by no later than July 15, 2012.

5.3. Calibration Gases Linde and AirGas representatives were contacted to discuss their ability to provide HCl calibration gases for calibration gas checks at 5, 10 ppm and 25 ppm which would provide linearity checks over the expected measurement range. Higher concentration spike gases (25 and 100 ppm) were also needed. Both companies indicated they could provide the gases. Linde indicated that the 5 ppm standard was not yet considered a commercial product. We planned to include SF6 in the spike gases as a tracer for determining the spike gas flow rate. ABB requested that the spike gases contain N2O as a tracer rather than SF6 as the quantification of N2O was part of their existing analysis routine and SF6 was not. After discussion, it was agreed that both SF6 and N2O would be included as tracers and both would be used to quantify spike gas flow rate for the ABB CEMS. Based on additional discussions with ABB and Thermo Fisher Scientific, it was concluded that 5 ppm SF6 would be used as a tracer in all spike gases and 350 ppm N2O would also be included in spike gases intended for use in the ABB system. The quantity of calibration gases that would be needed was estimated from expected response times, and sample flow rates. These estimates were reviewed by the

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respective vendors. Calibration gas orders were placed in early June with both Linde and AirGas with requested delivery dates by July 15.

5.4. Meeting with EPA at RTP NC On June 26, Glen Rosenhamer and Jim Peeler participated in a meeting at EPA offices in Research Triangle Park, NC with representatives of OAPQS and ORD to discuss the project scope and approach as a courtesy to EPA. A tour of EPA laboratory facilities where HCl measurement system evaluations were planned followed after the meeting.

5.5. Monitor Installation and Start-up CEMTEK completed its initial installation of the double pass TDL system during the week of July 9 which required only about 2 days: 1 day to install and 1 day to verify the installation. The stack mounted equipment, the accompanying purge blower, fiber optic and coaxial cables, and analyzer installation was completed on the first day. The second day was used to set up the analyzer and the remote wireless access. A 318.5 ppm HCl cylinder was employed to verify the calibration factor inputted into the analyzer. Analyte spikes were performed to verify the calibration factor for both area and peak measurement methods. The calibration factor for both methods was set to a lower value to match the cylinder concentration of 318.5 ppm. The area method was employed per advice from Unisearch that the area method would provide better measurements. 4-20 mA output to the DCS was verified to match the readings from the analyzer. Wireless access to the laptop interface was intermittent at best, given the location of the site. Subsequent modifications to improve the reliability of the remote access were completed by Rodney Miller at the behest of Paul Tran at CEMTEK. Thermo Fisher Scientific began installation June 19, but calibration gases were not available until July 18. Thermo Fisher Scientific encountered a number of issues and had teams of people on-site on several occasions. ABB planned to perform its installation and startup by July 15. However, it was found that the probe tube was not shipped with the other equipment. A number of problems were encountered including excessive calibration gas usage and apparent leaks. Initial installation was eventually completed by July 18, however problems with the low probe temperature were not yet resolved.

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5.6. Site Visit Shakedown July 25-26, 2012

A site visit was performed by Glen Rosenhamer and Jim Peeler on July 25 and 26 to verify operational status of the monitors. Gary Saunders from CEMSI was on-site to assist with the ABB monitor. Steve Johnson, Dave Glen and Jeremy Whorton were onsite from Thermo Fisher Scientific and working with David Martin from TRACE to complete installation of new CEMS software package for the OMNI FTIR CEMS. During the visit, problems with the ABB monitor, probe hook up, calibration gas flow rate, deviation between local and probe calibrations, etc. were investigated the morning of July 25. Saunders found and resolved several leaks and other problems. It was necessary for Holcim to reorder additional calibration gases for the ABB system because the NO/SO2/CO gas had been exhausted, the 25 ppm spike gas was low and a portion of the 100 ppm spike has been used. Analyte spikes were performed for the ABB system during the afternoon. The spike recoveries were acceptable and produced similar values for both the SF6 and N2O recovery calculations based on the direct analysis of the calibration gas cylinders. The Thermo Fisher Scientific /TRACE team was busy with the implementation of new software and various technical issues. Low throughput on the FTIR analysis cell was indicated but could not be resolved. Thermo Fisher Scientific worked through other items on a punch list resolving most. Direct and probe calibrations indicated disparity with calibration gas tag values. Analyte spikes were performed and initial spikes showed apparent losses of SF6. Further investigation revealed several leaks that were subsequently repaired. Negative SF6 readings for pre-spike effluent measurements were confusing and Thermo Fisher Scientific continued to investigate. Preliminary calibrations and analyte spikes were completed. The observations, actions taken to correct problems, decisions and conclusions regarding the status of the Thermo Scientific CEMS, as well as relevant data and results were documented in weekly reports, throughout the field project. The reports were submitted in a timely fashion and greatly helped facilitate effective decisions about how to proceed. The CEMTEK TDL seemed to operate properly and recorded plausible HCl data. No quantitative tests were performed for the TDL during the site visit.

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5.7. July 26 –Aug 10 Preparations continued for the tests planned to be conducted Aug. 13-17. Thermo Fisher Scientific and ABB representatives accessed their monitors and attempted daily drift checks and other diagnostics. Problems with excessive calibration gas usage and delayed replacement gas shipments arose. Thermo Fisher Scientific continued efforts with analyte spikes and attempted to resolve the check valve/spike flow and SF6 issues. CEMSI performed on-site corrective action to check calibration gas hook ups and flow rates and initiated a 7-day drift test. Excessive upscale calibration drift was observed for the ABB monitor. Discrepancies between monitoring results were observed and reported to specific suppliers. Problems in scaling of analog outputs were investigated. The project lurched along as the equipment suppliers attempted to address new challenges. Many of the seemingly puzzling issues are far less confusing and solutions are quite clear in retrospect. However, the confusion arising due to intermittent remote electronic access via cell phone networks, anecdotal verbal reports, discrepancies between digital and analog results for the same instrument, disparity in measurement results between instruments, participation of representatives from six companies and three countries, along with all the havoc mother nature and life can impose all took its toll. Some of the stories for individual monitors are interesting and informative, but are not included here to spare the reader. Representatives from SICK visited the St. Gen site Aug. 9-10 to inspect the MCS100E, perform preventive maintenance, and insure the HCl channel was functioning properly. An email report from SICK indicated that the MCS100E was in proper working order and no problems had been found.

5.8. Aug 10 - Test Postponed As the scheduled test data approached, operational concerns for the St. Genevieve plant and a planned outage expected to begin at the end of the week raised concerns and initiated discussions about means to compress the field test schedule. Late on Aug. 10, a decision was made to postpone the test and all parties were notified.

5.9. Aug 13-September 16 - Further CEMS Development Efforts The performance test was rescheduled for Sept. 17-21. The kiln did not return to operation until September 2. The rescheduled test provided more than a calendar month (and more than two additional weeks of kiln operation) for the equipment suppliers to address various issues. Details are included in monitor-specific sections of this report. Some highlights follow.

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CEMTEK/Unisearch installed an active effluent temperature measurement and temperature compensation feature to its monitor. This was done in recognition of the fact that the significant changes in effluent temperature for different kiln system operating modes (two mills on, one mill on, no mills on) necessitated corrections for both gas density and line strength absorbance to improve the accuracy of the data. The new feature was installed August 31. ABB sent personnel from Frankfurt Germany and from CEMSI to the St. Genevieve site to investigate apparent significant discrepancies between the ABB HCl measurements and other measurement systems and to verify the proper installation and operation of the ACF-NT. The investigation revealed that the heated sample line did not reach temperature at the probe end and needed to be replaced. Comparisons were performed between (a) Hovocal calibrations introduced at the analyzer and at the sample probe, and (b) injections of dry calibration gas and humidified calibration gas. Spectral analyses were verified by application of several different methods. Results were documented in an September 11 email from ABB and it concluded that the tag value of the compressed calibration gas must be in error. Based on all results and tools available to ABB/CEMSI, the system was believed to be working correctly except for the heated line issue. Plans were made, and the heated sample line was replaced with a new line from Germany. Thermo Fisher Scientific continued to investigate apparent slow response time and analyte spike issues. An increase sampling rate was tried and efforts were continued to resolve the check valve problems inhibiting performance of low spike dilutions. Thermo Fisher Scientific decided to install an integral pre-filter in the end of the probe stinger. Thermo Fisher Scientific visited the site and found and repaired several leaks, changed out the FTIR cell, installed the heated pre-filter, and investigate the sample flow rate and pressures. All activities were documented in the weekly reports. Intermittent discrepancies between the Thermo Fisher Scientific measurement results recorded from the instrument and data recorded in the plant TIS files were investigated. Thermo Fisher Scientific’s final site-visit was on the weekend prior to the test. Activities included changing out the FTIR source and detector, increasing the scan rate from 13 to 23 scans per minute, changing the sample line from the original ¼ inch tube to the 3/8 Teflon tube (previously used for blowback) to fix a damaged umbilical sample line (noting that the 3/8 inch line will not be used in the final system configuration),

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calibrations of the SO2, NO, CO channels, and improvements to the SF6 quantification which provided acceptable spike performance at, and above, 5% dilution.

5.10. Test Week Chronology 5.10.1. Monday Sept. 17– Jim Peeler arrived on-site and set up gas dilution manifold and

reviewed Thermo Fisher Scientific Weekly status report sent via email Sunday night. Phil Kauppi arrived, completed safety training for contractor, and began reference FTIR set-up. Multiple analyte spikes were performed for the CEMTEK/Unisearch TDL by Jim Peeler and Keith Mackay and the optical alignment was adjusted. Thirteen additional analyte spikes and LOS determination were performed for the TDL. Steen Jensen (SICK) and Rodney Miller performed gas injections on the MCS100E using an EMI Hovocal and determined the approximate sampling rate via empirical observation of spike flow rate necessary to prevent stack gas entering probe. They performed analyte spikes with nominal 33 ppm calibration gas. When completed the MCS was returned to service by Rodney Miller. Thermo Fisher Scientific checked automated zero check, found cylinder was turned off, ran manual zero and upscale calibration checks, ran nitrogen zero through probe, performed direct analysis of spike gas, ran three analyte spikes, made final changes to effluent SF6 quantification method, recalculated spike recoveries, and analyzed a nominal 5 ppm gas.

Two analyte spikes and one calibration gas injection calibrations were performed by Kon Bouttarath (CEMSI) for the ABB CEMS.

Phil Kauppi observed a discrepancy between the tag value of the HCl cylinder that he brought for test and his direct FTIR analysis. Several other cylinders were analyzed indicating discrepancies. These included cylinders that had been analyzed by Thermo Fisher Scientific and ABB and were suspected of having incorrect tag values.

Jim Peeler and Phil Kauppi performed a stratification test by sampling three measurement points on each of four traverses (12 points total) and determined that there was no evidence of HCl stratification and no evidence of spatial variation in CO2 or H2O or any other gas concentration due to air in-leakage. The

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measurements confirmed the obvious result apparent by simple inspection that there was no reason to expect stratification at the measurement location.

5.10.2. Tuesday – RATA test for two mills on. Thermo Scientific dynamic spike and zero

upscale calibration checks were performed by the automated sequence. Thermo Fisher Scientific and ABB personnel reviewed and/or performed manual calibrations of the CEMS under test and analyte spikes were completed. Nine 30-minute test runs were completed at very low HCl levels.

5.10.3. Wednesday – Arrived at plant at 4:30 am. Thermo Scientific dynamic spike and

zero upscale calibration checks were performed by the automated sequence. Initiated RATA for two mills off. A total of 18 sample runs were completed. HCl concentrations for Runs 1-9 ranged from 13.9 to 16.6 ppm. One analyte spike was performed by Jim Peeler for the TDL CEMS. Lime injection was initiated after completing Run 9, and for Runs 11-18 HCl concentrations decreased from 9.0 to 4.2 ppm. During the afternoon, the Thermo Scientific OMNI FTIR CEMS was removed from service and zero gas was directed to probe to check for sample filter/sample line contamination. Jim Peeler performed a dynamic spike for ABB/Prism system with temporary spike line after the RATA test was completed.

5.10.4. Thursday – Thermo Scientific dynamic spike and zero upscale calibration checks

were performed by the automated sequence. No calibration checks or spikes were possible for ABB/Prsim system. RATA for one mill on was performed. A total of 17 runs were completed. HCl concentrations for Runs 1-9 began at 3.1 ppm and decreased relatively steadily to 1.3 ppm. Five analyte spikes were performed by Jim Peeler for the TDL CEMS. Lime injection was increased to lower effluent concentrations to provide an additional test level. Run 10-17 HCl concentrations ranged from 1.3 ppm to 0.1 ppm.

5.10.5. Friday – Thermo Scientific dynamic spike and zero upscale calibration checks

were performed by the automated sequence. Prism performed analysis of numerous HCl cylinders. Jim Peeler and Rodney Miller attempted to perform linearity gas injections for the ABB CEMS but were not successful. Jim Peeler performed calibration gas injections for MCS100E and analyte spikes at two levels.

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5.11. EPA Site Visit September 25

Ray Merrill and Robin Segall from EPA’s, Office of Air Quality Planning and Standards visited the St. Gen plant on September 25. Preliminary results and data were reviewed and discussed. A tour of the monitoring location and instrument systems was provided.

5.12. Second Meeting with EPA at RTP NC On November 1, 2012, Glen Rosenhamer and Jim Peeler participated in a meeting at EPA offices in Research Triangle Park, NC with representatives of OAPQS and ORD to discuss the project results and findings as a courtesy to EPA. After the meeting, discussions continued during a tour of EPA laboratory facilities where HCl measurement system evaluations were planned, but had been delayed due to problems with the combustor facility, and other issues.

5.13. November 19 Draft Project Report A preliminary draft project report was completed during October, and relevant sections were provided to the equipment suppliers for review. Written comments were received, and conference calls were held to resolve some issues. A revised complete report was prepared dated Nov. 19, and was distributed to equipment suppliers for further review.

5.14. December 19 Project Report Technical corrections and additions, and editorial changes were incorporated based on internal reviews and comments received from equipment suppliers. A separate report prepared by ABB and CEMSI entitled “Addendum To: Field Evaluation of HCl CEMS at Holcim St. Genevieve Plant Report” dated December 17, 2012 has been received. This report describes the activities, field tests, and results obtained by ABB and CEMSI after the September 21, 2012.

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6. Test Procedures Reference measurements of HCl were provided by Phil Kauppi of Prism Analytical Technologies Inc. using an MKS 2030 liquid nitrogen cooled FTIR with MCT detector operating at approximately 60 scans per minute and one half wave number resolution. Samples were acquired at approximately 10 liters per minute through a heated probe, heated filter, and heated sample line all maintained above 377°F. The sample pump is located downstream of the FTIR measurement cell and the concentration measurements are compensated for the actual pressure within the cell. The procedures used and data acquired during this test project are presented in a separate report. The test procedures and equipment used for this project are essentially the same as used in many short term cement kiln area source tests performed since 1999 by Prism and EMI requiring measurement of HCl and other parameters. The data from the area source tests is included in the EPA Subpart LLL rulemaking docket and was used by EPA in establishing the new HCl emission limit for cement kilns. It is important that the same procedures are now used to characterize the performance of HCl CEMS that may be used to determine continuous compliance with HCl emission standards. It is important to understand that the field test was conducted under strict time and budget constraints. Furthermore, as with most all preheater/precalciner cement kilns with in-line raw mills (in this case two raw mills) there are significant operational constraints on the times and duration of operation with raw mills off. The St. Genevieve plant went to extraordinary lengths to accommodate the testing program and operate the kiln system under a wide variety of conditions during the performance test. It was clear to EMI and Prism that the two mills off operating condition was a one chance opportunity. The entire test week was organized around the expected kiln system operating schedule. The test procedures were optimized and adjusted to provide the most useful information that could be obtained in the time available.

6.1. Stratification Test Procedures There is no reasonable basis to expect spatial variation if the HCl concentration, or any other gaseous component, across the stack cross section at the measurement location. This is apparent because the ID fans on the baghouse outlet completely mix the effluent streams, which then travel through relatively long ducts with turns and additional mixing at the stack breeching, and then travel 147 feet (or further) through the stack to the sampling location.

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Nevertheless, a stratification test was performed on Monday afternoon for demonstration purposes because the EPA draft performance specifications include this requirement and some EPA representatives have asserted that it is necessary. The stack internal diameter is 218.9 inches (5.56 meters) at the measurement location. Prism’s longest probe available for this project has an effective reach of 2.134 meters from the inside stack wall. Three sample points were traversed on each of four radial traverses at 90 degree intervals around the stack. The sample points were located at 2.134, 1.42, and 0.711 meters from the stack wall on each traverse. The inner most points on opposite traverses were 1.29 meters apart. These sample points are better placed for identifying spatial variation in pollutant concentration then are the Method 1 points (where the inner sample point sample points are 2.28 meters apart and the outer sample points are only 0.45 meters from the wall). Sampling was performed for a sufficient period to acquire at least 5 one-minute average measurements at each sample point. The probe was then moved to the next sample point on the traverse, or the next sample port. The test was performed on Monday afternoon during which kiln operation was relatively constant. It was not necessary, and no attempt was made to correct the measurement data for temporal variations. (If this was necessary, then any of the 3 other multi-parameter measurement systems or the cross-stack TDL could have been used as the temporal reference.) The one-minute measurements for each sample point were averaged. The data are included in the Prism report. Applying the standard EPA criteria for the presence of stratification (deviation of any measurement point by more than 10% of the average), review of the data demonstrates:

• All one minute HCl measurements (as well as all point average HCl measurements) were less than the nominal limitation of detection for the Prism FTIR (0.1 ppm). Therefore, the HCl concentration is less than the background noise of the measurement system, and hence it would never be possible to discriminate a 10% relative concentration difference.

• Using H2O as a surrogate to indicate the presence of stratification due to ambient air in-leakage, the mean H2O concentration measured by the FTIR was 13.6% by volume with a STD of 0.05% by volume. The maximum deviation of any one sample point from the mean was 0.1% H20, which is equal to 0.81% of the mean value, and is much less than 10% of the mean.

• Using CO2 as a surrogate to indicate the presence of stratification due to ambient air in-leakage, the mean CO2 concentration measured by the FTIR was 18.74% by

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volume with a STD of 0.07% by volume. The maximum deviation of any one sample point from the mean was 0.14% CO2, which is equal to 0.74% of the mean value, and is much less than 10% of the mean.

• Subsequent HCl testing during the two mill off condition and elevated HCl concentrations showed that the PRISM FTIR, the Thermo Scientific OMNI FTIR CEMS, the ABB ACF-NT FTIR CEMS, the SICK MCS100E multi-parameter CEMS, and the cross-stack TDL all read within about ±0.2 ppm HCl. This also clearly demonstrates the absence of pollutant stratification.

• The stratification test took longer than two hours of EMI and Prism’s time to prepare and perform. Additional time for data analysis was necessary.

6.2. RATA Test Procedures

All effluent samples for the three days of RATA testing were collected at a single point approximately 2 meters from the inside stack wall. Individual RATA test runs were of 30 minutes duration and included approximately 30 consecutive discrete effluent measurements (each determined from 60 scans). Considering the variability of emissions from the St. Genevieve kiln system at any particular operating condition, this period is more than sufficient to eliminate any concerns about minor differences in data averaging, or calculation of rolling averages from three successive measurements, differences in monitor response time, etc..

For the first RATA (two mills on), the testing began by performing dynamic spikes before and after each test run. The lack of any measurable HCl present in the effluent, together with desire to obtain accurate very low level measurements near the LOD of the reference FTIR system, required long periods (approximately 45 minutes) to initiate and stabilize the dynamic spike, record steady responses and then allow the reference measurement system to completely recover, (i.e., re-equilibrate) at 0.1 ppm. After several test runs, all with successful spike recoveries, Jim Peeler decided that spikes would be performed before and after every three runs (90 minutes of testing) in order that the objectives of the test program could best be accomplished. The dynamic spikes are used to demonstrate that the reference measurement system is working. The spike results are not used to adjust the measurement data (as is done with instrumental Methods such as Method 6C, 7E, etc.).

Six dynamic spikes were performed during the “two mills on” RATA consisting of 9 test runs. Seven spikes were performed during the “two mills off” RATA which

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included 18 test runs. Seven spikes were performed during the “one mill on” RATA which included 17 test runs. All spike recoveries were between 91% and 104% as compared to the acceptable tolerance of 70% to 130% in Method 321.

6.3. Dynamic Spike Test Procedures

Dynamic spikes (a.k.a. “analyte spikes”) consist of the quantitative addition of the analyte of concern (HCl) to the sample and the subsequent determination of whether the change in the analyzer response is consistent with the amount of analyte spiked into the sample. It is similar to the “method of standard additions” often used for laboratory analysis, except that the spike is added continuously to a continually flowing sample stream. Hence the term “dynamic spike” is often used. (See “EPA Handbook for Continuous Monitoring of Non-Criteria Air Pollutants” for a general discussion.)

Dynamic spikes are a far more extensive challenge to a monitoring system than a simple injection of a dry calibration gas containing HCl in nitrogen because the components in the effluent stream which cause problems for HCl measurements (H2O, NH3, methane, etc.) are present in the spiked samples but are not present in the dry calibration gases. Thus for example, if there are HCl losses due to a cold spot and absorption by condensed water, or reaction of HCl with NH3 to form ammonium chloride salts, these losses can be detected with a properly performed dynamic spike but not necessarily by a traditional calibration. Also, if the specific analysis procedure used by an instrument requires compensation for (including measurement and subtraction) analytical interferences (e.g. H2O and formaldehyde), errors in the analysis can be detected with a properly performed dynamic spike. These errors cannot be detected by a traditional dry gas calibration injection. In order that the spiked sample matrix is similar to (representative) of the effluent samples (i.e., contains about the same level of the problem compounds), the spike should not be more than 10% of the total sample. In addition, the amount of the analyte spike should be a reasonable addition relative to the measurements of concern. For example, Method 321 recommends that the spike approximately doubles the native HCl concentration, or for low levels, adds 5 ppm of HCl.

In expectation of HCl concentrations of about 10-15 ppm for two mills off, and lower concentrations for other kiln operating conditions, spike gases with nominal HCl concentrations of 100 ppm and 25 ppm were ordered. Spiking 10% of a 100 ppm gas adds roughly 10 ppm to the effluent sample (not accounting for dilution of the

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native HCl concentration). Similarly, spiking 5% of a 100 ppm gas adds roughly 5 ppm to the effluent sample. Using the 25 ppm spike gases, lower level concentration spikes are possible.

A widely used practice is to add a non-reactive and easily measured tracer compound to the spike gas which can be quantified simultaneously by the instrument system. Sulfur hexafluoride (SF6) is often used for many FTIR systems as a tracer because SF6 has a large infrared absorption, is easily measured at low concentrations (especially for liquid nitrogen cooled MCT detectors.) and is not present in the effluent. 5 ppm of SF6 is a good cylinder concentration for some FTIRs.

In view of the lack of traceable HCl gas standards, and serious concerns about the accuracy of the tag value analysis and their instability, the HCl and SF6 values are established in the field by introducing the undiluted spike gas directly to the gas measurement cell. The HCl and SF6 are quantified in the absence of interfering compound relative to the FTIR reference spectra which are unchanging (often calculated from HiTran reference spectra or well established laboratory experiments). The direct analysis rather than the tag values are used in spike recovery calculations.

The HCl spike recovery calculations used during this project for systems that also measure SF6 are:

𝐶𝐸𝑥𝑝𝑒𝑐𝑡𝑒𝑑 = 𝐶𝑁𝑎𝑡𝑖𝑣𝑒 �1 − 𝑆𝐹6𝑂𝑏𝑠𝑒𝑟𝑣𝑒𝑑𝑆𝐹6𝐵𝑜𝑡𝑡𝑙𝑒

� + 𝐶𝑆𝑝𝑖𝑘𝑒 𝐺𝑎𝑠 �𝑆𝐹6𝑂𝑏𝑠𝑒𝑟𝑣𝑒𝑑𝑆𝐹6𝐵𝑜𝑡𝑡𝑙𝑒

� (Eq. 1)

Where:

CExpected = HCl expected concentration response for dynamic spike (i.e., analyte spike) based on the sum of the diluted native concentration and spike addition

CNative = HCl concentration present in the sample gas without spike added

SF6Observed = Concentration of SF6 observed during dynamic spike gas injection concurrent with stable spiked HCl response

SF6Bottle = Concentration of SF6 in spike gas determined from direct analysis of the spike gas

30

CSpike Gas = HCl concentration of spike gas as determined from direct analysis of the spike gas

%𝑅 = 𝐶𝑂𝑏𝑠𝑒𝑟𝑣𝑒𝑑𝐶𝐸𝑥𝑝𝑒𝑐𝑡𝑒𝑑

× 100 (Eq. 2)

Where:

%R = Dyanmic Spike Recovery expressed as a percentage of expected value

CObserved = HCl concentration observed after stable response is achieved during dynamic spike

CExpected = HCl expected concentration response for dynamic spike (i.e., analyte spike) based on the sum of the diluted native concentration and spike addition calculated from Equation 1

ABB preferred use of N2O as a tracer since it was already a compound included in their TUV certified analysis routines. The concentration of N2O in the cylinder must be significantly higher due to the N2O absorption characteristics and the calculations of spike recovery must take into account that that there is a low level of N2O present in the effluent samples. Jim Peeler derived HCl spike recovery calculations for the use of N2O as a tracer.The HCl spike recovery calculations used during this project for systems that also measure N2O are:

𝐶𝐸𝑥𝑝𝑒𝑐𝑡𝑒𝑑 = 𝐶𝑁𝑎𝑡𝑖𝑣𝑒 �1 − 𝑁2𝑂𝑂𝑏𝑠𝑒𝑟𝑣𝑒𝑑−𝑁2𝑂𝑁𝑎𝑡𝑖𝑣𝑒𝑁2𝑂𝐵𝑜𝑡𝑡𝑙𝑒− 𝑁2𝑂𝑁𝑎𝑡𝑖𝑣𝑒

� + 𝐶𝑆𝑝𝑖𝑘𝑒 𝐺𝑎𝑠 �𝑁2𝑂𝑂𝑏𝑠𝑒𝑟𝑣𝑒𝑑−𝑁2𝑂𝑁𝑎𝑡𝑖𝑣𝑒𝑁2𝑂𝐵𝑜𝑡𝑡𝑙𝑒− 𝑁2𝑂𝑁𝑎𝑡𝑖𝑣𝑒

�

(Eq. 3)

Where:

CExpected = HCl expected concentration response for dynamic spike (i.e., analyte spike) based on the sum of the diluted native concentration and spike addition

CNative = HCl concentration present in the sample gas without spike added

N2OObserved = Concentration of N2O observed during dynamic spike gas injection concurrent with stable spiked HCl response

31

N2ONative = N2O concentration in the sample gas without spike added

N2OBottle = Concentration of N2O in spike gas determined from direct analysis of the spike gas

CSpike Gas = HCl concentration of spike gas as determined from direct analysis of the spike gas

The percent spike recoveries for the N2O spikes are calculated using Equation 2 above based on the ratio of observed and expected HCl concentrations, the same as with the SF6 Calculations.

Spreadsheet templates were developed and provided to Thermo Fisher Scientific and ABB as examples for spike recovery calculations.

6.4. Limitation of Detection (LOD) and Limitation of System (LOS) Test Procedures

The traditional method for determining the limitation of detection (LOD) is to calculate the noise limited detection usually expressed as two times the standard deviation of the noise at the zero concentration level. Such a determination adopts the premise that the HCl signal cannot be reliably detected until it is twice as large as the standard deviation of the background. This LOD test is often performed for a “representative analyzer” under laboratory conditions.

LOD determinations can also be performed using humidified air or humidified nitrogen samples. For some instruments the LOD result may be different for dry and wet gases. Some manufacturers also calculate the LOD at elevated HCl concentrations by introducing an elevated concentration during an analyte spike (or dry calibration gas) and again reporting the standard deviation or (2σ) of the noise apparent in the measurement response. It is important to determine exactly how results are reported (1σ, 2σ and 3σ) as conventions vary.

LOD tests without the analyte present (noise at the zero level) demonstrate a one-sided fundamental limitation. Measurements cannot be made below this level. However, they provide no information about what can be measured. When performed for a representative instrument in the laboratory, they provide no information about the sampling system’s ability to transport HCl to the detector in the presence of dirty filters with cement kiln dust, HCl ammonia and water vapor

32

adsorption on sample lines and sample transport components, analytical interferences, and other problems. Reliance on laboratory LOD determinations for analyzers allows (and perhaps invites) equipment suppliers to grossly overstate the abilities of their measurement systems.

The Holcim Project Scope requested that the LOD for the entire CEMS (probe to analyzer) be determined using three methods. The first two methods were the noise limited calculation approaches described above for dry and humidified zero gases. The third approach, which will now be referred to as Limitation of System (LOS), was to present dynamic spikes of sequentially decreasing concentration to determine the HCl concentration at which the spiked and unspiked HCl samples were indistinguishable. Using a 25 ppm HCl spike gas with 5 ppm SF6, and assuming that SF6 can be quantified at 0.04 ppm yields an potential spike level at 0.2 ppm HCl. Lower SF6 levels can be achieved by some FTIR analyzers and /or external mass flow meters can be used to create even lower spike flow rates, as necessary.

33

7. Thermo Scientific OMNI FTIR Results CEMS Results and Observations

7.1. Description The Thermo Scientific OMNI FTIR CEMS is a Pilot/Beta unit not yet released for sale to commercial clients and is still under development and refinement. The CEMS as tested included a heated pre-filter (sintered steel filter maintained at 220° C), heated stinger, heated M&C replaceable primary filter, heated sample line, Thermo Scientific Antaris IGS 0.5 wavenumber resolution FTIR with 5.2 meter multi-pass gas cell, and thermo-electrically cooled DTGS detector. The system includes IMACC software for FTIR analysis, and a system controller operating a Trace Environmental System software package for system control and data reporting. The CEMS is equipped with blowback for the probe stinger/pre-filter. The system includes a proprietary humidified “flowback” feature which can be activated to direct humidified zero gas back through the sample line, primary particulate filter and probe stinger/pre-filter. The system is fully automated and can be programmed to perform zero and upscale HCl calibrations, zero and upscale calibrations of other parameters (NO, SO2, CO, CO2 etc.). It also configured to perform dynamic spikes which can be triggered automatically on periodic basis, by remote access through cell phone or other internet access, or performed manually, at any time by an operator.

7.2. Installation and Start-Up Thermo Fisher Scientific sent teams of several people to the St. Genevieve site for the initial installation, start-up and on several additional occasions up until the test week. As would be expected for a Pilot/Beta unit, a variety of problems were encountered and the Thermo Fisher Scientific personnel worked to resolve them. Detailed reports for each site visit were prepared and provided to Holcim. The reports included a detailed step-by-step recount of exactly what was done and observed, analysis of the results and discussion of next steps, and where appropriate presentation of results with explanatory graphs and charts. The reports along with discussions during periodic conference calls with Holcim provided a coherent explanation and understanding of what was being done in a systematic and organized problem solving approach. In general, the Thermo Fisher Scientific reports contain data and information which may be considered as proprietary information and are therefore not included in this report but are retained as the record of what was done. As an exception, the report dated

34

9/24/2012 is included at the end of this section as Fig. 7-6 and covers the period of the test week. In addition, to on-site evaluations, Thermo Fisher Scientific ran additional experiments via the remote access and with the assistance of St. Genevieve personnel from time to time, and performed experiments on similar equipment at their facilities. Other Pilot/Beta prototype OMNI FTIR evaluations were conducted over the same time period as the St. Genevieve study. Note: For the purposes of this evaluation it was requested and agreed that raw one-minute averages would be provided (Thermo Fisher Scientific had considered averaging several consecutive measurements) and that no adjustments or corrections would be applied by the DAS, even though such corrections are allowed under all EPA regulations. The analysis of unadjusted measurement results was expected to provide the fullest understanding of the technical issues. The RATA results are determined for the unadjusted data and are reanalyzed for the Thermo Scientific OMNI FTIR applying a zero correction based on daily zero calibration check responses obtained during the early morning hours of the RATA test days.

7.3. RATA Tests The traditional Part 60 relative accuracy specification for SO2, NOx and most other pollutant gas CEMS is ≤20% of the reference measurement value or ≤10% of the emission standard, whichever is least restrictive. This specification is used for the Holcim project as a tentative specification. The relative accuracy is calculated as the sum of the absolute value of the differences and the 95% confidence coefficient, divided by either the mean reference measurement result or the emission standard, to express the result as a percentage. The emission standard is 3 ppm at 7% O2, dry basis. For the purposes of this comparison, we will simply use 3 ppm HCl as the emission standard.

7.3.1. Two Mills On RATA Tests

The two mills on RATA results are shown in Table 7-1. For this low concentration test, the OMNI FTIR CEMS relative accuracy was 4.9% of the emission standard. The CEMS meets the RA requirement. A small mean difference of +0.1 ppm shows that CEMS measurements are slightly greater than the reference measurements.

Table 7-1 THERMO CEMS Two Mills On RATA Calculations

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 18-Sep 9:00 - 9:30 0.23 0.12 0.11 0.012 18-Sep 10:11 - 10:40 0.33 0.15 0.18 0.033 18-Sep 11:16-11:46 0.29 0.14 0.15 0.024 18-Sep 11:47 - 12:17 0.24 0.11 0.13 0.025 18-Sep 12:18 - 12:48 0.24 0.09 0.15 0.026 18-Sep 13:19 - 13:48 0.24 0.17 0.07 0.007 18-Sep 13:50 - 14:19 0.20 0.11 0.09 0.018 18-Sep 14:21 - 14:50 0.21 0.10 0.11 0.019 18-Sep 15:16 - 15:46 0.22 0.16 0.06 0.00

SUM 1.15 1.05 0.14AVG 0.24 0.13 0.12 0.02

RATA RESULTSAverage Difference 0.12Standard Deviation 0.04

Confidence Coefficient 0.03 Relative Accuracy % 115%

Relative Accuracy ppm 0.15 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 4.91% % of STD

36

7.3.2. Two Mills OFF RATA Tests

The two mills off RATA results for the OMNI FTIR CEMS are shown in Table 7-2 based on 17 of the 18 runs performed. (CEMS operation was interrupted during run 15, to run diagnostic checks.) For this high concentration test, the OMNI FTIR CEMS relative accuracy was 13.6% which meets the 20% relative accuracy specification. The mean difference was 0.88 ppm reflecting that the OMNI FTIR values were, on average, higher than the reference FTIR measurements.

Lime injection was increased after the first nine sampling runs were completed to reduce the effluent HCl concentrations. During the test, the OMNI FTIR measurements did not decrease as quickly as the reference FTIR measurements. Diagnostic checks were performed during run 15 as the differences continued to increase after run 10. It appeared as though the previous high concentrations had contaminated some portion of the sampling system which was desorbing HCl during subsequent runs.

The relative accuracy test procedures allow for the rejection of three test runs, as long as nine test runs are reported. The two mills off RATA results were recalculated based on nine test runs (omitting run 1, and using runs 2-10) as shown in Table 7-3. The relative accuracy based on these nine test runs was 1.7% of the reference value, and shows excellent agreement with the reference FTIR system.

7.3.3. One Mill On RATA Tests

For this test, 17 reference test runs were completed. HCl concentrations began above 3 ppm and decreased throughout the day as lime injection was increased on several occasions. The OMNI FTIR CEMS relative accuracy was calculated for runs 1-17 and the results were 43.7% of the reference value and 19.5% of the emission standard as shown in Table 7-4, which does not meet the relative accuracy specification. The mean difference was 0.53 ppm reflecting that OMNI FTIR values were greater than the reference FTIR measurements.

The one mill on RATA results were recalculated based on 9 “best” test runs as shown in Table 7-5. The relative accuracy based on 9 test runs was 32.3% of the reference value and 17.6% of the emission standard. The mean difference for the best nine runs was 0.45 ppm.

Table 7-2 THERMO CEMS Two Mills Off Rata Calculations (17 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 19-Sep 6:58 - 7:26 14.48 13.86 0.62 0.382 19-Sep 7:28 - 7:58 14.43 14.18 0.25 0.063 19-Sep 7:59 - 8:29 14.93 14.68 0.25 0.064 19-Sep 8:38 - 9:07 15.65 15.29 0.36 0.135 19-Sep 9:09 - 9:39 15.67 15.43 0.24 0.066 19-Sep 9:40 - 10:10 15.84 15.59 0.25 0.067 19-Sep 10:16 - 10:47 15.95 16.08 -0.13 0.028 19-Sep 10:47 - 11:16 16.33 16.46 -0.13 0.029 19-Sep 11:16 - 11:46 16.57 16.59 -0.02 0.00

10 19-Sep 11:53 - 12:23 15.47 15.74 -0.27 0.0711 19-Sep 12:24 - 12:54 10.71 8.99 1.72 2.9612 19-Sep 12:55 - 13:25 9.97 6.40 3.57 12.7413 19-Sep 13:38 - 14:08 8.66 5.31 3.35 11.2214 19-Sep 14:09 - 14:39 4.40 4.86 -0.46 0.2116 19-Sep 15:18 - 15:46 4.94 4.41 0.53 0.2817 19-Sep 15:58 - 16:18 6.64 4.30 2.34 5.4818 19-Sep 16:19 - 16:49 6.58 4.12 2.46 6.05

SUM 207.22 192.29 14.93 39.81AVG 12.19 11.31 0.88 2.34

RATA RESULTSAverage Difference 0.88Standard Deviation 1.29

Confidence Coefficient 0.66 t = 2.12Relative Accuracy 13.6%

Table 7-3 THERMO CEMS Two Mills Off Rata Calculations (Runs 2-10)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

2 19-Sep 7:28 - 7:58 14.43 14.18 0.25 0.063 19-Sep 7:59 - 8:29 14.93 14.68 0.25 0.064 19-Sep 8:38 - 9:07 15.65 15.29 0.36 0.135 19-Sep 9:09 - 9:39 15.67 15.43 0.24 0.066 19-Sep 9:40 - 10:10 15.84 15.59 0.25 0.067 19-Sep 10:16 - 10:47 15.95 16.08 -0.13 0.028 19-Sep 10:47 - 11:16 16.33 16.46 -0.13 0.029 19-Sep 11:16 - 11:46 16.57 16.59 -0.02 0.00

10 19-Sep 11:53 - 12:23 15.47 15.74 -0.27 0.07SUM 140.84 140.04 0.80 0.48AVG 15.65 15.56 0.09 0.05

RATA RESULTSAverage Difference 0.09Standard Deviation 0.23

Confidence Coefficient 0.17Relative Accuracy 1.7%

Table 7-4 THERMO CEMS One Mill On Rata Calculations (17 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 20-Sep 8:00 - 8:30 3.41 3.21 0.20 0.042 20-Sep 8:30 - 9:00 3.00 2.35 0.65 0.423 20-Sep 9:00-9:30 2.56 2.05 0.51 0.264 20-Sep 9:41-10:11 2.32 1.84 0.48 0.235 20-Sep 10:12-10:42 2.28 1.66 0.62 0.386 20-Sep 10:42 - 11:12 1.99 1.53 0.46 0.217 20-Sep 11:22 - 11:52 1.90 1.44 0.46 0.218 20-Sep 11:52 - 12:22 1.88 1.35 0.53 0.289 20-Sep 12:22 - 12:52 1.86 1.30 0.56 0.31

10 20-Sep 13:06 - 13:36 1.74 1.21 0.53 0.2811 20-Sep 13:36 - 14:06 1.53 1.06 0.47 0.2212 20-Sep 14:06 - 14:36 1.44 0.85 0.59 0.3513 20-Sep 15:00 - 15:30 1.09 0.49 0.60 0.3614 20-Sep 15:30 - 16:00 1.16 0.54 0.62 0.3815 20-Sep 16:00 - 16:30 1.48 1.05 0.43 0.1816 20-Sep 16:59 - 17:29 1.39 0.71 0.68 0.4617 20-Sep 17:29 - 17:59 0.64 0.07 0.57 0.3218

SUM 31.67 22.71 8.96 4.92AVG 1.86 1.34 0.53 0.29

RATA RESULTSAverage Difference 0.53Standard Deviation 0.11

Confidence Coefficient 0.06 t =2.12Relative Accuracy 43.7%

Relative Accuracy ppm 0.58 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 19.5% % of STD

Table 7-5 THERMO CEMS One Mill On Rata Calculations (Best 9 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 20-Sep 8:00 - 8:30 3.41 3.21 0.20 0.043 20-Sep 9:00-9:30 2.56 2.05 0.51 0.264 20-Sep 9:41-10:11 2.32 1.84 0.48 0.236 20-Sep 10:42 - 11:12 1.99 1.53 0.46 0.217 20-Sep 11:22 - 11:52 1.90 1.44 0.46 0.218 20-Sep 11:52 - 12:22 1.88 1.35 0.53 0.28

10 20-Sep 13:06 - 13:36 1.74 1.21 0.53 0.2811 20-Sep 13:36 - 14:06 1.53 1.06 0.47 0.2215 20-Sep 16:00 - 16:30 1.48 1.05 0.43 0.18

SUM 18.81 14.74 4.07 1.92AVG 2.09 1.64 0.45 0.21

RATA RESULTSAverage Difference 0.45Standard Deviation 0.10

Confidence Coefficient 0.08Relative Accuracy 32.3%

Relative Accuracy ppm 0.53 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 17.6% % of STD

41

7.3.4. Re-Analyzed RATA Tests with Zero Offset

The Thermo Scientific OMNI FTIR CEMS performs daily zero calibration checks each morning as part of an automated calibration check sequence. The typical response to the zero check during the performance test week was 0.25 ppm. If the OMNI FTIR CEMS RATA data are reanalyzed accounting for a 0.25 ppm offset in the Thermo Fisher Scientific data, the results would be:

Two Mills On 5.5% of emission standard (from 4.9%) Two Mills Off 11.4% of reference value (from 13.2%) One Mill On (17 runs) 25% of reference value (from 43.7%) 11.1% of emission standard (from 19.5%) One Mill On (9 runs) 15.5% of reference value (from 32.3%) 8.5% of emission standard (from 17.6%) Using zero corrected data, the OMNI FTIR CEMS would pass the relative accuracy test specification at all three test conditions.

7.4. Dynamic Spikes

Thermo Fisher Scientific personnel performed dynamic spikes throughout the start-up period as a diagnostic tool and for the purpose of refining the automated procedure. During the July 25-26 site visit, attempted dynamic spikes helped reveal leaks in the CEMS manifold that were not apparent during pressurization with calibration gas for probe calibrations. The results of dynamic spikes performed prior to the test week are documented in the reports prepared by Thermo Fisher Scientific. After the final adjustments were completed to the OMNI CEMS on September 16, dynamic spikes were performed on each day during the test week and the results were documented in EXCEL files provided to Holcim. On Sept. 17, a new “nominal 25 ppm” spike cylinder was hooked up to the spike line, which had previously been exposed to ambient air for about an hour, and had been purged with nitrogen. The new gas was analyzed at a spike flow rate of 6 lpm (100% spike gas) and the rise time was 16 minutes (longer than expected, probably due to reconditioning the spike line and installation of a new cylinder). The stable value was 17.36 ppm indicated by the OMNI FTIR. (Prism

42

analyzed the same gas and reported a 17.8 ppm HCl value). The OMNI FTIR SF6 reading for the cylinder was 4.98 and agrees closely with the SF6 tag value of 4.93 ppm. The “direct” analysis of the spike cylinder by the OMNI FTIR must be used for spike recovery calculations because the tag values are not reliable or accurate. Three consecutive manual spikes were performed at a nominal spike rate of approximately 10%. The initial SF6 responses were determined to be invalid due to a linearity issue in the SF6 method. The SF6 method was revised and the data were re-quantified. The SF6 background measurements when spikes are off are negative values but the algebraic difference in these values and the spiked responses are used in the calculations. This approach and the revised SF6 quantification method were used throughout the test. Each spiked and un-spiked HCl and SF6 measurement response was determined as the average of approximately 20 one-minute values. The three consecutive manual spike recoveries (%R) were 61%, 75%, and 88%, respectively. The second two spike recoveries are acceptable. The increasing spike recoveries are attributed to conditioning of the test equipment. An automated analyte spike was performed on Sept 18 at approximately 4 a.m. using the 17.4 ppm spike gas at a dilution rate of 12%. A graphic depiction of the spike is shown in Figure 7-1. The %R was 98.4%. An automated analyte spike was performed on Sept 19 at 4 a.m. during a period when the effluent HCl concentration was decreasing. The spike was performed using the 17.4 ppm spike gas at a dilution rate of 10.7%. A graphic depiction of the spike is shown in Figure 7-2. The %R was 105.0% as calculated from the spike response and post-spike effluent HCl concentration. The %R was 100.1% as calculated from the spike response and average of the pre- and post-spike effluent HCl concentrations. The %R was 83.6% as calculated from the spike response and difference from a baseline polynomial fit to the effluent HCl concentrations. This example shows the sensitivity of the dynamic spike procedure to temporal changes during the spike, and several ways to address the issue. An automated analyte spike was performed on Sept 20 at 4 a.m. while the effluent concentrations were about 9 ppm using the 17.4 ppm spike gas at a dilution rate of 10.5%. A graphic depiction of the spike is shown in Figure 7-3. The %R was 97.7%. Ideally, a higher concentration spike would be performed at

-0.5

0

0.5

1

1.5

2

2.5

3

9/18/2012 3:21 9/18/2012 3:36 9/18/2012 3:50 9/18/2012 4:04 9/18/2012 4:19 9/18/2012 4:33 9/18/2012 4:48

Figure 7-1 HCl Dynamic Spike Sept. 18

HCl

HCl = 0.464 ppm

HCl = 0.300 ppm

HCl = 2.381ppm

Recovery Rate = 0.984

0

2

4

6

8

10

12

9/19/2012 3:21 9/19/2012 3:36 9/19/2012 3:50 9/19/2012 4:04 9/19/2012 4:19 9/19/2012 4:33 9/19/2012 4:48

Figure 7-2 HCl Dynamic Spike Sept. 19

HClHCl =4.520 ppm

HCl =2.741 ppm

Recovery Rate = 1.050

HCl = 3.211 ppm

0

2

4

6

8

10

12

9/20/2012 3:21 9/20/2012 3:36 9/20/2012 3:50 9/20/2012 4:04 9/20/2012 4:19 9/20/2012 4:33 9/20/2012 4:48

Figure 7-3 HCl Dynamic Spike Sept. 20

HCl

Spike Started Spike Ended

Stack HCl = 9.382 ppm Stack HCl = 9.116 ppm Spike HCl = 9.866 ppm

Recovery Rate = 0.977

0

0.5

1

1.5

2

2.5

3

9/21/2012 3:21 9/21/2012 3:36 9/21/2012 3:50 9/21/2012 4:04 9/21/2012 4:19 9/21/2012 4:33 9/21/2012 4:48

Figure 7-4 HCl Dynamic Spike Sept. 21

HCl

Stack HCl = 0.465 ppm Stack HCl = 0.480 ppm

Spike HCl = 2.000 ppm

Recovery Rate = 0.859

47

elevated HCl effluent levels. However, this is not possible for automated spikes performed in the middle of the night without an attendant, and it is not possible to predict when elevated HCl concentrations will be encountered. An automated analyte spike was performed on Sept 21 at approximately 4 a.m. while the effluent values were more variable (“noisy”) again using the 17.4 ppm spike gas at a dilution rate of 11%. A graphic depiction of the spike is shown in Figure 7-4. The %R was 85.9%. The above spikes demonstrate some of the challenging circumstances associated with conducting analyte spikes, especially for an automated procedure. A series of decreasing concentration analyte spikes was performed on Sept. 21 again using the 17.4 ppm HCl cylinder but with dilution rates controlled by EMI’s dilution manifold. The lowest dilution rates were used for a LOS determination (described later). Calculations of spike recoveries was not intended, but were pretty good anyway. The results in Table 7-6 were obtained for the OMNI FTIR CEMS.

Table 7-6 Decreasing Concentration Analyte Spikes Dilution Ratio % % Recovery

10.8% 105 5.2% 105 3.6% 98 1.7% 113 0.5% 118

7.5. Compressed Gas Cylinder Analysis The unreliable tag values for the HCl calibration gases caused much confusion, consternation, and consumed a lot of resources during the entire project, to say the least. The OMNI FTIR CEMS analyzed a number of these gases (some of which were also analyzed by Prism). The following is an excerpt from Steve Johnson’s Sept. 24 report:

Multiple calibration cylinders were analyzed during last week with the following results. On average, the HCl cylinders that we have data for were 25% lower than the vendor’s analyzed concentration according to Prism and Thermo Fisher Scientific’s readings were 1.5% higher than Prism’s readings for the same HCl cylinders:

48

Date Vendor Cylinder Number

Gases Vendor Analyzed Conc (ppm,

% analytical accuracy)

Prism Reading (ppm, % of cylinder conc)

Thermo Reading (ppm,

% of Prism reading)

Cylinder Pres (psi)

9/17 SO2

NO

CO

79.28

275.3

472.8

78.49

271.9

463.0

500

9/17 Linde HCl

SF6

25.3

4.93

17.8, -29.6%

4.74, -3.9%

17.36, -2.5%

4.99, +5.3%

2100

9/17 Airgas HCl 5.395 4.107, -23.9% 4.24, +3.2% 1800

9/21 Airgas CC220612 NH3 9.731, 5% 8.52, -12.4% 8.42, -1.2% 1950

9/21 CC135201 CO2 20100 179300 1800

9/21 Linde CC118783 SO2

NO

CO

78.1, 2%

279, 2%

465, 2%

78.57

274.1

463.9

9/21 CC352084 HCl 11.59, 5% 8.65, -25.4% 8.90, +2.9% 800

9/21 HCl 11.49 8.90, -22.5% 9.10, +2.2% 1000

The OMNI FTIR analysis of calibration gases agrees well with the reference FTIR analysis of the same gases.

7.6. Zero and Upscale Calibration Checks and Drift Tests

7.6.1. Criteria Pollutants Zero and upscale calibration drift tests were performed by automated gas injections for the SO2, NO, and CO monitoring channels using instrument air and a single SO2/NO/CO certified gas mixture. The drift test began on Sept. 17. It was necessary to change out the certified gas mixture on Sept. 21 because the cylinder pressure was low. The drift test results are presented in Steve Johnson’s Sept. 24 report as % of span (See Figure 7-6 at the end of this Section). The span values are: SO2 = 160 ppm, NO = 550 ppm, CO = 1500 ppm. All of the zero drift

49

checks were less than ±0.2% of span for the three parameters. All of the upscale calibration drift checks were less than ±1.0% of span for SO2, NO, and CO monitoring channels. The OMNI FTIR CEMS easily meets the applicable drift criteria for the criteria pollutants contained in Performance Specifications 2 and 4 of Part 60, Appendix B.

7.6.2. HCl The HCl zero and upscale responses shown in Table 7-7 were recorded without any correction or adjustment applied:

Table 7-7 OMNI FTIR CEMS Zero and Upscale HCl Checks Date Manual/Auto

Time Zero ppm

Zero Std. ppm

Upscale ppm

Upscale Std ppm

9/17 Manual 9:12 0.07 9.15 0.44 9/18 Auto 4:00 0.018 0.056 9.30 0.29 9/19 Auto 4:00 0.221 0.19 9.07 9/19 Manual

20:36 0.17 0.18

9/20 Manual 2:52 0.103 0.106 9/20 Auto 4:00 0.139 0.119 8.79 0.269 9/21 Auto 4:00 0.126 0.155 9.103 0.358 9/21 Manual

10:20 0.110 0.090

Some of the manual zero gas injections were performed to assess the CEMS condition after sampling high concentrations of HCl and ammonia. The data show that the OMNI FTIR CEMS could likely achieve a zero drift limit of ± 0.25 ppm and an upscale drift limit of ± 0.50 ppm based on uncorrected values for a short term test. However, the standard deviation of measurement values during the checks shows that averaging the response over a reasonable interval is necessary. Additional data over a much longer period is needed to assess long term drift and stability.

7.7. Limitation of Detection (LOD) and Limitation of System (LOS)

7.7.1. The LOD can be calculated as two times the standard deviation of the HCl zero responses for dry gas (zero air or nitrogen) injections. Alternatively, the LOD for

50

infrared based measurements can be calculated as two times the standard deviation of the HCl zero responses for wet gas measurements to account for measurement “noise” due to water vapor interference. The zero offset that is observed for the OMNI FTIR CEMS, and likely all HCl measurement devices, is dependent on the concentrations and conditions that the CEMS has been exposed to, at least recently, as well as the duration of the zero gas injections. For example, after sampling during the elevated HCl and NH3 concentrations for many hours such as those encountered during the two mills off RATA (15 ppm HCl and 45 ppm NH3) the system will require a long period to recover. A residual zero offset and increased “noise” at the zero concentration may be observed. (Note the difference in the zero responses in Table 7-7 for 9/17 and 9/18 when effluent concentrations were very low as compared to the zero responses for 9/19 and 9/20 after elevated emissions.) The time interval used for the daily zero checks injections is not sufficient for the LOD determination.

The effects of the sample system are removed if the zero gas is introduced directly to the measurement cell. Such results reflect the capability of the analyzer rather than the entire measurement system. However, these are the commonly reported values.

For the Thermo Scientific OMNI FTIR CEMS the direct zero gas injections to the

analyzer have been performed at several sites and Thermo Fisher Scientific reports a 2σ LOD of 0.1 ppm. This is equivalent to a 3σ LOD of 0.15 ppm.

7.7.2. An empirical LOS determination was performed for the entire measurement

system on Sept. 21 using EMI’s dilution manifold with mass flow meters to control the spike gas injection rate to very low levels. The HCl responses to various spikes are shown in Figure 7-5. The lowest spike, introduced at a dilution rate of 0.5% of the sample flow (50 ccm) produced a visibly apparent difference from the baseline HCl response to the effluent. This very clearly demonstrates that the entire CEMS is able to transport concentrations ≤0.22 ppm of HCl introduced to the dirty side of the primary particulate matter filter, through the 25 meter heated line to the measurement cell, and produce a quantitative measurement response under real world conditions while monitoring cement kiln effluent. It is likely that the Thermo Scientific OMNI FTIR CEMS could demonstrate even lower LOS, however, the HCl background response at the time the test was performed was about 0.3 ppm HCl.

0

0.5

1

1.5

2

2.5

3

9/21/2012 7:12 9/21/2012 7:40 9/21/2012 8:09 9/21/2012 8:38 9/21/2012 9:07 9/21/2012 9:36 9/21/2012 10:04 9/21/2012 10:33

Figure 7-5 HCl Dynamic Spikes for LOS Determination

HCl

Stack HCl = 0.431 ppm Stack HCl = 0.356 ppm

HCl = 2.343 ppm Recovery = 1.050

HCl = 1.348 ppm Recovery = 1.051

HCl = 0.990 ppm Recovery = 0.980

HCl = 0.766 ppm Recovery = 1.131

HCl = 0.571 ppm Recovery = 1.181

The system can discern less than 0.22 ppm HCl

Figure 7-6 OMNI FTIR BASED CEMS Status Report

Report Date: September 24, 2012

Preparer Name: Stephen Johnson

Model Code & Options: 70-BNNP020CN

Describe any maintenance or system changes made since last report: Numerous entries in this section have been removed to avoid disclosure of proprietary information and/or intellectual property of Thermo Fisher Scientific.

Describe the system’s current operating status: System was used for RATA last week, data has been provided to Holcim. After swapping the sample and blowback lines in the sample line on 9/16 to address blockage in the sample line, the new sample line had to be conditioned. After sampling stack gas for over 24 hours, It appeared to be OK during the daily spike check on 9/18 and afterwards. The sample and FTIR cell input line temperatures were increased from 180 to 190 degrees Celsius on 9/20 at 07:50 and continue to run at that temperature today. SF6 method was modified on Monday 9/17 at 15:45 to address high readings during spikes, the same method was used all week and is still being used now. This method does show a negative bias on stack gas due to CO2/H2O/NH3 interferences, but this bias was factored in to all spiking calculations. Switched to sample stack gas about 14:30 on Friday 9/21 and has been sampling stack gas ever since except for the daily calibration tests which are all being conducted. The daily calibration check cylinders are currently: Spike: HCl 25.3 ppm, SF6 4.93 ppm (Prism reads HCl 17.8 ppm, SF6 4.74 ppm)(1775 psi 9/19 15:00) Span1: HCl 11.49 ppm (Prism reads 8.9 ppm)(1000 psi 9/21 14:10) Span2: SO2 78.1 ppm, NO 279 ppm, CO 465 ppm (new cylinder, didn’t record pressure)

Report daily drift levels: All drift levels are reported as a % of span concentration (HCl = 60 ppm, SO2 = 160 ppm, NO = 550 ppm, CO = 1500 ppm). Zero Drift:

Span Drift:

Note that the SO2/NO/CO mixture cylinder was changed the day of 9/21 due to low cylinder pressure and the deviations in readings are within the 2% analytical precision of the new cylinder. List any necessary maintenance that should be performed:

• None List any other actions:

• Holcim should periodically check cylinder pressures and swap out cylinders when the pressure is low (and notify Thermo of the new analyzed and expected concentrations to add to the chart below).

Additional Comments: Multiple calibration cylinders were analyzed during last week with the following results. On average, the HCl cylinders that we have data for were 25% lower than the vendor’s analyzed concentration according to Prism and Thermo’s readings were 1.5% higher than Prism’s readings for the same HCl cylinders: Date Vendor Cylinder

Number Gases Vendor

Analyzed Conc (ppm, % analytical accuracy)

Prism Reading (ppm, % of cylinder conc)

Thermo Reading (ppm, % of Prism reading)

Cylinder Pres (psi)

9/17 SO2 NO CO

79.28 275.3 472.8

78.49 271.9 463.0

500

9/17 Linde HCl SF6

25.3 4.93

17.8, -29.6% 4.74, -3.9%

17.36, -2.5% 4.99, +5.3%

2100

9/17 Airgas HCl 5.395 4.107, -23.9% 4.24, +3.2% 1800 9/21 Airgas CC220612 NH3 9.731, 5% 8.52, -12.4% 8.42, -1.2% 1950 9/21 CC135201 CO2 20100 179300 1800 9/21 Linde CC118783 SO2

NO CO

78.1, 2% 279, 2% 465, 2%

78.57 274.1 463.9

9/21 CC352084 HCl 11.59, 5% 8.65, -25.4% 8.90, +2.9% 800 9/21 HCl 11.49 8.90, -22.5% 9.10, +2.2% 1000

56

8. ABB ACF-NT CEMS Results and Observations 8.1. Description

The ABB ACF-NT CEMS is an FTIR-based CEMS with a ZRO2 oxygen sensor and options for addition of a FID analyzer. The system includes a heated probe and heated filter, heated sample gas line and heat 6.4 meter gas cell. The FTIR is 1.0 wavenumber resolution and is equipped with a thermoelectrically cooler DGTS detector. The measurement system is TÜV certified for measurement of many compounds including HCl. The system ABB installed for the Holcim project included a high pressure blowback probe and was specially configured to allow for conduct of automated zero and upscale calibration drift tests using compressed gas standards. It was also specially configured with provisions to conduct manual analyte spikes. CEMSI installed the system and provided a Limesoft DAS for recording of data. Detailed descriptions of the CEMS and components were provided in product literature provided by CEMSI.

8.2. Installation and Start-Up

The installation, start-up and subsequent trouble shooting for the ABB CEMS began in early July to meet the July 15 deadline and continued through replacement of the heated sample line during the week preceding the September 16 performance test. Some delay occurred at the start because the heated probe tube was not received with the other equipment. Issues were encountered regarding the calibration gas hookups, leaks in the system resulted in venting of several calibration gas cylinders and excessive calibration gas usage. Several site visits were made by CEMSI to address these and other issues. After these problems were thought to be resolved, 7-day zero and upscale drift tests were initiated. However, the upscale calibration responses indicated an unacceptable deviation and the tests were stopped.

Informal inter-comparison of HCl monitoring data showed that the ABB CEMS was reading quite differently than the other monitoring systems. Long term data for the measurement of other parameters was provided by Holcim to aid in trouble shooting. ABB reanalyzed data using several different spectral analysis procedures and concluded that the system was operating correctly. Problems with incorrect HCl cylinder gas tag values made problem resolution much more difficult. Eventually, ABB sent a

57

representative from ABB Frankfurt along with a CEMSI representative to conduct an on-site investigation.

The investigation revealed that the heated sample line was well below the acceptable temperature for a considerable distance from the point at which it connected to the sample probe assembly. During the investigation, Hovocal generated HCl standards and humidified standards were injected both locally to the FTIR cell and at the heated probe. Proper responses were observed. However, the injection of dry calibration gases produced measurement results much lower than the tag values. ABB concluded that the system was working correctly based on all available means to evaluate it, and that the tag value of the cylinder was incorrect. ABB’s assessment of the cylinder tag value was later demonstrated to be consistent with analyses of the same cylinder by Prism and by Thermo and is judged to be a correct conclusion. However, ABB’s conclusion that the CEMS was performing correctly was not correct as was determined by subsequent tests.

8.3. RATA Tests The traditional Part 60 relative accuracy specification for SO2, NOx and most other pollutant gas CEMS is ≤20% of the reference measurement value or ≤10% of the emission standard, whichever is least restrictive. This specification is used for the Holcim project as a tentative specification. The relative accuracy is calculated as the sum of the absolute value of the differences and the 95% confidence coefficient, divided by either the mean reference measurement result or the emission standard, to express the result as a percentage. The emission standard is 3 ppm at 7% O2, dry basis. For the purposes of this comparison, we will simply use 3 ppm HCl as the emission standard.

8.3.1. Two Mills On RATA Tests

The two mills on RATA results are shown in Table 8-1. For this low concentration test, the ABB CEMS relative accuracy was 22.7% of the emission standard. The CEMS does not meet the RA requirement, primarily because of the +0.63 ppm average mean difference (CEMS measurements are greater than the reference measurements).

Table 8-1 ABB AFC-NT Two Mills On RATA Calculations

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 18-Sep 9:00 - 9:30 0.89 0.12 0.77 0.592 18-Sep 10:11 - 10:40 0.82 0.15 0.67 0.453 18-Sep 11:16-11:46 0.77 0.14 0.63 0.404 18-Sep 11:47 - 12:17 0.73 0.11 0.62 0.385 18-Sep 12:18 - 12:48 0.68 0.09 0.59 0.356 18-Sep 13:19 - 13:48 0.70 0.17 0.53 0.287 18-Sep 13:50 - 14:19 0.71 0.11 0.60 0.368 18-Sep 14:21 - 14:50 0.75 0.10 0.65 0.429 18-Sep 15:16 - 15:46 0.76 0.16 0.60 0.36

SUM 6.81 1.15 5.66 3.59AVG 0.76 0.13 0.63 0.40

RATA RESULTSAverage Difference 0.63Standard Deviation 0.07

Confidence Coefficient 0.05 Relative Accuracy % 532%

Relative Accuracy ppm 0.68 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 22.7% % of STD

59

8.3.2. Two Mills OFF RATA Tests

During the night preceding this condition, kiln system operating conditions resulted in elevated and varying HCl emission concentrations as indicted by other HCl CEMS but not by the ABB CEMS. After completing QA activities for the reference system, it and the other CEMS showed that emissions were emissions were above 12 ppm and increasing. The ABB CEMS indicated less than 3 ppm emissions with very little increase. It was obvious that something was wrong. Jim Peeler and Phil Kauppi offered to assist Kon Bouttarath in trouble shooting. A quick comparison of the NO, CO, CO2, and H2O monitoring parameters for the ABB CEMS and the reference FTIR and the other CEMS showed reasonable agreement. However, the ABB CEMS read less than one third of the HCl concentrations and less than one-third of the NH3 concentrations indicated by the other measurement systems. This strongly suggests that there was a sampling problem with likely ammonium chloride salt formation somewhere in the sampling system. The ABB sample line was disconnected, and there was a small indication of HCl and NH3 desorption from the line while sampling ambient air, but of small consequence. A TEE fitting was installed on the open end of the sample line and the spike line was connected to one leg so that a dynamic spike could be performed while sampling ambient air. Calculating the spike recoveries from the ABB direct analysis or the Prism re-analysis of the system resulted in acceptable spike recoveries. This result suggested that the problem was in the ABB sample probe/filter assembly.

Phil Kauppi and Jim Peeler offered to build a probe and filter system from Prism and EMI spare parts and fittings that would be equivalent to the reference FTIR sampling system. Rodney Miller made provisions for additional electrical power to operate the heated probe and filter oven. The connection of the ABB heated line to the Prism heated filter oven was imperfect but was made a closely as possible and insulted as best could be done. The work was completed as quickly as possible during the first few runs of the RATA. The new Prism probe/filter was preheated and then inserted into the stack. The ABB CEMS measurements immediately began to increase, and by the beginning of the fourth RATA test run were comparable to the reference measurements at about 15 ppm.

60

The two mills off RATA results for the ABB CEMS with Prism probe and filter are shown in Table 8-2. For this high concentration test, the ABB/Prism CEMS relative accuracy was 11.3% based on runs 5-18, which is acceptable. Looking at the differences for the individual runs it appears that the ABB/Prism CEMS was still catching up for the first two runs and then exhibited a positive high bias of about 1 ppm for the remainder of the test.

After run 9, the plant lime injection was restarted to reduce HCl emission concentrations. It appeared as though the ABB/Prism CEMS did not fall as rapidly as the reference FTIR measurements. Calculating the relative accuracy from the last nine runs provide result of 17.9% which was acceptable, but also showed a mean difference of +1.09 ppm for the ABB/Prism CEMS as shown in Table 8-3. During the test, this raised concerns that there might be a cool spot at the junction of the heated line and the probe box resulting in some ammonium chloride adsorption and desorption as the HCl concentrations varied..

8.3.3. One Mill On RATA Tests

The ABB/Prism unit ran through the night and was used for the one mill on RATA. For this test 17 reference test runs were completed. HCl concentrations began above 3 ppm and decreased throughout the day as lime inject was increased on several occasions. The ABB CEMS relative accuracy was calculated for runs 1-15 (runs 16 and 17 were flagged) and the results were 62.1% of the reference value and 30.3% of the emission standard, as shown in Table 8-4. The CEMS does not meet the RA requirement, primarily because of the +0.85 ppm average mean difference (CEMS measurements are greater than the reference measurements).

After removing the Prism probe from the stack with the ABB sample line still connected, the apparent positive offset disappeared quickly. This observation suggests that there was no cold spot at the junction of the ABB sample line and the Prism filter oven, and suggests instead that there may be some analytical interference when stack gases are sampled.

Further troubleshooting of the ABB probe system was performed during the RATA, including de-powering the filter heater and removal of filter element, visual inspection, and subsequent removal of the entire probe, and washing with clean water. Rust or corrosion was seen in the

Table 8-2 ABB AFC-NT Two Mills Off RATA Calculations (All Valid Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 19-Sep 6:58 - 7:26 under repair 13.862 19-Sep 7:28 - 7:58 under repair 14.183 19-Sep 7:59 - 8:29 under repair 14.684 19-Sep 8:38 - 9:07 under repair 15.295 19-Sep 9:09 - 9:39 14.94 15.43 -0.49 0.246 19-Sep 9:40 - 10:10 15.76 15.59 0.17 0.037 19-Sep 10:16 - 10:47 16.49 16.08 0.41 0.178 19-Sep 10:47 - 11:16 17.15 16.46 0.69 0.489 19-Sep 11:16 - 11:46 17.77 16.59 1.18 1.39

10 19-Sep 11:53 - 12:23 16.74 15.74 1.00 1.0011 19-Sep 12:24 - 12:54 10.20 8.99 1.21 1.4612 19-Sep 12:55 - 13:25 7.37 6.40 0.97 0.9413 19-Sep 13:38 - 14:08 6.50 5.31 1.19 1.4214 19-Sep 14:09 - 14:39 6.02 4.86 1.16 1.3515 19-Sep 14:40 - 15:10 5.74 4.61 1.13 1.2816 19-Sep 15:18 - 15:46 5.57 4.41 1.16 1.3517 19-Sep 15:58 - 16:18 5.35 4.30 1.05 1.1018 19-Sep 16:19 - 16:49 5.04 4.12 0.92 0.85

SUM 150.64 138.89 11.75 13.04AVG 10.76 9.92 0.84 0.93

RATA RESULTSAverage Difference 0.84Standard Deviation 0.49

Confidence Coefficient 0.29 t = 2.160Relative Accuracy 11.3%

Table 8-3 ABB AFC-NT Two Mills Off RATA Calculations (Last 9 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

10 19-Sep 11:53 - 12:23 16.74 15.74 1.00 1.0011 19-Sep 12:24 - 12:54 10.20 8.99 1.21 1.4612 19-Sep 12:55 - 13:25 7.37 6.40 0.97 0.9413 19-Sep 13:38 - 14:08 6.50 5.31 1.19 1.4214 19-Sep 14:09 - 14:39 6.02 4.86 1.16 1.3515 19-Sep 14:40 - 15:10 5.74 4.61 1.13 1.2816 19-Sep 15:18 - 15:46 5.57 4.41 1.16 1.3517 19-Sep 15:58 - 16:18 5.35 4.30 1.05 1.1018 19-Sep 16:19 - 16:49 5.04 4.12 0.92 0.85

SUM 68.53 58.74 9.79 10.74AVG 7.61 6.53 1.09 1.19

RATA RESULTSAverage Difference 1.09Standard Deviation 0.11

Confidence Coefficient 0.08 t = 2.306Relative Accuracy 17.9%

Table 8-4 ABB AFC-NT One Mill On RATA Calculations (17 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 20-Sep 8:00 - 8:30 3.90 3.21 0.69 0.482 20-Sep 8:30 - 9:00 3.39 2.35 1.04 1.083 20-Sep 9:00-9:30 3.01 2.05 0.96 0.924 20-Sep 9:41-10:11 2.78 1.84 0.94 0.885 20-Sep 10:12-10:42 2.64 1.66 0.98 0.966 20-Sep 10:42 - 11:12 2.43 1.53 0.90 0.817 20-Sep 11:22 - 11:52 2.35 1.44 0.91 0.838 20-Sep 11:52 - 12:22 2.22 1.35 0.87 0.769 20-Sep 12:22 - 12:52 2.15 1.30 0.85 0.72

10 20-Sep 13:06 - 13:36 1.99 1.21 0.78 0.6111 20-Sep 13:36 - 14:06 1.87 1.06 0.81 0.6612 20-Sep 14:06 - 14:36 1.69 0.85 0.84 0.7113 20-Sep 15:00 - 15:30 1.23 0.49 0.74 0.5514 20-Sep 15:30 - 16:00 1.27 0.54 0.73 0.5315 20-Sep 16:00 - 16:30 1.71 1.05 0.66 0.4416 20-Sep 16:59 - 17:29 Flagged Data 0.7117 20-Sep 17:29 - 17:59 Flagged Data 0.0718

SUM 34.63 21.93 12.70 10.93AVG 2.31 1.46 0.85 0.73

RATA RESULTSAverage Difference 0.85Standard Deviation 0.11

Confidence Coefficient 0.06 t =2.145Relative Accuracy 62.1%

Relative Accuracy ppm 0.91 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 30.3% % of STD

64

compartment upstream of the filter compartment and discolored water and other solid material flowed from the probe barrel. It was apparent that a large section of the probe between the heated probe barrel and heated filter element was unheated (except for some conduction from heated filter element). This section was un-insulated and in fact bolted to the protective enclosure, which in this case, aided in cooling of the flanged section.

8.4. Dynamic Spikes

Preliminary dynamic spikes were performed during the July 25-26 shakedown visit using a cylinder with a HCl tag value of 25.88 ppm. Using the bottle tag values for a 9.1% spike, the spike recovery calculated based on SF6 tracer was 86.7% and the recovery based on N2O tracer was 87.2%. As stated in the test procedures section (and demonstrated elsewhere in this study) the cylinder tag values are not reliable. Using the values from ABB’s direct analysis of the cylinder, the spike recovery calculated based on SF6 tracer was 94.2% and the recovery based on N2O tracer was 95.7%. The native N2O concentration was 2.9 ppm prior to the spike and very constant. These results show that the use of the SF6 and N2O tracers are equivalent for the ABB system under these conditions.

Dynamic spikes for the ABB system can only be performed manually. Few spikes were performed during site visits that have been reported.

Two dynamic spikes were performed on Sept. 17 by CEMSI. The results submitted by CEMSI in the field (subsequently corrected for an error in the spike calculation template) were based on the cylinder tag values and are shown in Table 8-5. The spike performed at 11:40 am revealed low spike recoveries of 73.0% to 81.7% for the SF6 and N2O tracers, respectively. A second spike performed at 13:20 showed spike recoveries of 81.6% and 91.3% for the SF6 and N2O tracers, respectively, as reported by CEMSI. The reason for the difference between the first and second spike responses is not known.

The September 17 dynamic spikes were recalculated by EMI based on the ABB direct analysis of the cylinder, which is the correct procedure. The results are shown in Table 8-6. The same relative difference is seen between the first and second spikes and the reason for this is not known. The spike recoveries for the second spike were 89.9% for SF6 and 101.4% for N2O tracer.

Table 8‐5  ABB Analyte Spikes Based on Tag ValuesHCl SF6 N2O

Cal Bottle 28.55 4.169 350.5Bottle Pressure: 11:40 (start)Bottle Pressure: 12:20 (end)

Run TimeSpike Gas

Injection RateInstrument 

Injection Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 8 11:40 260 1.06 0 2.89End 12:20 260 3.66 0.6 46.16 5.016 4.482 72.96% 81.66%

HCl SF6 N2OCal Bottle 28.55 4.169 350.5Bottle Pressure: 13:20 (start)Bottle Pressure: 14:03 (end)

Run TimeSpike Gas

Injection RateInstrument 

Injection Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 8 13:20 260 0.81 0 3.05End 14:03 260 3.92 0.6 46.67 4.802 4.293 81.63% 91.32%

Analyte Spike Calculation TemplateInstrument ABBDate: 9/17/2012

Table 8‐6  ABB Analyte Spikes Based on Direct AnalysisHCl SF6 N2O

Cal Bottle 25.55 4.18 356.23Bottle Pres 11:40 (start)Bottle Pres 12:20 (end)

Run Time

Spike GasInjection Rate

Instrument Injection 

Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 8 11:40 260 1.06 0 2.89End 12:20 260 3.66 0.6 46.16 4.575 4.059 79.99% 90.17%

HCl SF6 N2OCal Bottle 25.55 4.18 356.23Bottle Pres 13:20 (start)Bottle Pres 14:03 (end)

Run Time

Spike GasInjection Rate

Instrument Injection 

Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 8 13:20 260 0.81 0 3.05End 14:03 260 3.92 0.6 46.67 4.361 3.866 89.88% 101.41%

67

CEMSI performed another dynamic spike beginning at 15:40 on Sept. 18 after the RATA was completed. The results are shown in Tables 8-7 and 8-8 using the tag values and using the direct analysis values, respectively. The spike recoveries based on direct analysis of the cylinder were 81% and 85.6% based on SF6 and N2O tracers respectively. These spikes indicate low spike recovery.

Spikes for the ABB CEMS were introduced on the dirty side (upstream) of the PM filter. However, as was identified by the events during the RATA test, the spikes were introduced downstream of the cold spot in the ABB sample probe. Hence all, dynamic spike results above are representative only of the analyzer and heated line performance, and the native HCl concentration measurements are not correct.

A dynamic spike was performed on Sept. 19 as a troubleshooting measure after disconnecting the ABB sample line while the CEMS was sampling ambient air. The spike results showed the ABB system responded appropriately using the cylinder values from Prism’s analysis of the cylinder. (Spike recoveries of 87.5% and 102.6% for SF6 and N2O, respectively.)

After completing the Sept. 19 RATA testing, Jim Peeler performed a dynamic spike for the ABB/Prism CEMS using the EMI calibration manifold and a temporary spiking line to reach the temporary probe system. The spike recoveries based on direct analysis of the cylinder were 103.6% and 102.2% based on SF6 and N2O tracers, respectively and are shown in Table 8-9. The very good spike recoveries are consistent with the successful RATA for the ABB/Prism CEMS at the high HCl concentration.

The CEMSI Hovalcal used to control the spike gas flow rate was removed and shipped to another job site on Sept. 20. No additional spikes were performed.

8.5. Compressed Gas Cylinder Analysis No assembled report of the compressed gases analyzed by the ABB ACF-NT has been provided. Based on data in emails and on-site conversations it is clear that some of the gases analyzed by ABB were re-analyzed by Prism. The following are some examples:

Example Compressed Gas Analysis Certified Value (ppm) ABB Analysis (ppm) Prism Analysis (ppm)

28.55.(CC267989) 25.55 21.10 10.1 (CC-18216) 6.72 6.01

11.59 (CC352084) 8.80 8.65

Analyte Spike Calculation TemplateInstrument:Date: 9/18/2012

Table 8-7 ABB Analyte Spike on Sept. 18 Based On Tag ValueHCl SF6 N2O

Cal Bottle 28.55 4.169 350.5Bottle Pressure: (start)Bottle Pressure: (end)

Run Time

Spike GasInjection

Rate

Instrument Injection

Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 15:50 260 0.78 0 3.8End 16:01 260 3.03 0.5 43.08 4.111 3.926 73.71% 77.17%

Analyte Spike CalculationInstrument: ABB spikeDate: 9/18/2012

Table 8-8 ABB Analyte Spike on Sept. 18 Based On Direct Analysis ValueHCl SF6 N2O

Cal Bottle 25.55 4.18 356.23Bottle Pressure: (start)Bottle Pressure: (end)

Run TimeSpike Gas

Injection RateInstrument

Injection Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 0.78 0 3.8End 3.03 0.5 43.08 3.743 3.541 80.95% 85.58%

Analyte Spike CalculationInstrument: B CEMS with PRISM probeDate: 9/19/2012

Table 8-9 ABB Analyte Spike on Sept. 19 of ABB CEMS with Prism probeHCl SF6 N2O

Cal Bottle 25.55 4.18 356.23Bottle Pressure: (start)Bottle Pressure: (end)

Run TimeSpike Gas

Injection RateInstrument

Injection Rate HCl SF6 N2OConcentration

ExpectedConcentration

Expected % Recovery % Recovery(#) (00:00) (cc) (l/min) (ppm) (ppm) (ppm) (ppm, SF6) (ppm, N2O) (SF6) (N20)

Start 5.92 0.0 3.91End 8.08 0.4 39.60 7.798 7.909 103.61% 102.17%

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8.6. Zero and Upscale Calibration Checks and Drift Tests Automated zero and upscale calibrations were initiated on several occasions. The tri-blend gas for the NO/SO2/CO calibrations was exhausted. Problems were encountered for the HCl drift tests. After leaks and other issues were believed to be resolved, the drift test was re-started on Aug. 3. The drift results reported for the next few days for a nominal 10 ppm value were: -0.58, -0.25, -0.62, -0.94, -1.80, -0.76 ppm. For comparison, EPA’s draft drift specification is 5% of span. EPA formally proposed changes to 40CFR63, Subpart LLL (Federal Register Vol. 77, No. 138 July 18, 2012 page 42409) that HCl CEMS for cement plants use a span value of 5 ppm. This proposal would result in a zero and upscale drift limit of ±0.25 ppm. Alternatively, if the span value is 10 ppm for HCl CEMS at a cement plant ( a more reasonable level), the drift limit would be ±0.5 ppm. The observed ABB ACF-NT CEMS HCl upscale drift was unacceptable and the test was stopped. A successful 7-day zero and upscale drift test had not been completed for either the conventional monitoring channels (SO2, NO, CO, CO2) of the ABB CEMS installed at St. Genevieve nor was a successful zero and upscale drift test completed for the HCl monitoring channel by the end on the test week (Sept. 21.).

8.7. Limitation of Detection (LOD) and Limitation of System (LOS) The HCl detection limit stated in the ACF-NT operating manual is 0.16 ppm and the minimum measuring range is 0-10 ppm HCl. Review of the TUV report on approval testing (TUV Report No.: 936/21210471/A dated Feb. 13, 2009) Table 18 Repeatability of standard deviation at zero for HCl provides a standard deviation of device 3 of 0.08 mg/m3 and of device 4 of 0.06 mg/m3. Three times the standard deviation at the zero concentration, (3σ LOD) expressed in ppm is 0.16 and 0.12 ppm for devices 3 and 4, respectively. The LOD can be calculated from dry zero gas injections as three times the standard deviation of the noise. The LOD can also be determined in a similar manner for humidified zero gas injections. The Holcim Project Scope asked the equipment suppliers to do both dry and wet gas LOD determinations. ABB and CEMSI personnel made these determinations while on-site Sept. 4 and the

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results are presented in EXCEL files attached to Norbert Will’s e-mail report dated Sept. 11, 2012. For dry gas injections, the 3σ LOD was 0.146 ppm HCl with a mean HCl response value of -0.066 ppm. For wet gas injections containing 14.7% H2O, the 3σ LOD was 0.184 ppm HCl with a mean HCl response value of 0.381 ppm. It is noted that the mean HCl response to 14.7% H2O gases containing no HCl is more than twice the 3σ LOD result. The same calculation can be performed for any constant HCl emission level from dry gases or dynamic spikes. Results from dynamic spikes of a nominal 25 ppm HCl cylinder also performed by ABB and CEMS personnel on Sept. 4 provide the following results:

ACF-NT LOD Determinations from Analyte Spikes dilution rate HCl ppm SDTV LOD

28% 7.00 0.05 0.156 16% 4.02 0.05 0.152 12% 2.90 0.04 0.117 9% 2.13 0.02 0.066

The mass flow meters in the Hovacal provided by CEMSI could not be operated below about 250 ccm. Thus, the lowest dynamic spike possible is about 7-8% or 1.75 ppm. This is not sufficient for the LOS determination by introducing successively lower spike concentrations to determine the lowest HCl concentration that can be detected by the measurement system under actual conditions. We had planned to do an LOS determination using EMI’s calibration manifold. However if view of the events of the RATA, this effort was not undertaken because it is not possible to introduce spikes upstream of the cold spot for the ABB CEMS. During the two mills on RATA, the effluent HCl concentration was 0.15 ppm or less, as determined by the reference system. The ACF-NT indicated an average value of 0.76 ppm for the nine runs. For the system and analysis as currently configured, the value 0.76 ppm can be used as the LOS for the measurements on kiln system effluent at the St. Genevieve plant.

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9. CEMTEK/Unisearch TDL Results and Observations

9.1. Description The monitor is a cross-stack tunable diode laser (TDL) which measures HCl concentrations but does not measure any other effluent component. CEMTEK decided at the outset to install a double-pass system to achieve the optimum sensitivity for the St. Genevieve installation. The transmitter and associated receiver are installed on the same side of the stack within a protective enclosure. The reflector is installed on the opposite side of the stack within a protective enclosure. Filtered ambient air is supplied to both devices by purge air blowers to protect the optical components from contamination. The transmitter and receiver are connected by optical fiber to the analyzer which was located on a table in the CEMS shelter. (The fiber optic cables allow the analyzer to be installed at any convenient location, including great distances away from the stack mounted components). The analyzer is a small box (19x11x6 inches) and can be rack mounted. The analyzer contains a sealed internal audit cell which is used for stability checks based on a small portion of light diverted by a stationary beam splitter to a second detector internal to the analyzer A permanently installed flow through audit cell is also installed in the normal measurement light path. This cell can be filled with HCl calibration gas to provide an incremental calibration check similar to an extractive dynamic spike because the effluent stream also remains in the optical path. The audit cell must be purged with dry air or nitrogen after performing incremental calibrations/spikes to remove the HCl calibration gas. The measurement system is operated, and measurement results are recorded, by a laptop computer. A secondary box contained electronics and remote communication connections, and later including active effluent temperature measurement devices, was located next to the analyzer. CEMTEK/Unisearch also provided a spreadsheet for calculating the expected response to spikes that takes into account the path length of the effluent measurement and the path length of the audit cell and it also accounts for adsorption line strength as a function of stack temperature.

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9.2. Installation and Start-Up A local CEMTEK representative completed the initial installation of the double pass TDL system on July 12 and 13 which required only about one and one-half days. The monitor was installed in two opposite 4 inch sample ports normally used for stack testing. CEMTEK representatives installed an active temperature measurement and temperature compensation system on Aug. 31 to improve the accuracy of the monitoring data in view of the significant effluent temperature variations that occur during varying kiln operating conditions. The fundamental calibration of the TDL CEMS is established by Unisearch at its factory relative to a fixed gas cell containing a known amount of HCl. After installation at St. Genevieve, the calibration factor was evaluated and then changed so that the monitor provided the correct response to the introduction of a known calibration gas in the flow through cell. A calibration gas with a certified gas value of 318.5 ppm HCl was used. Later, the same cylinder was re-analyzed during the test week using the reference FTIR and was found to contain 294 ppm. The original factory calibration factor was subsequently adjusted and the TDL monitoring data were re-processed to the 318.5 ppm gas value. Other changes to the analysis methods used were made. The methods used to establish the TDL calibration and the changes that were made are documented in correspondence from CEMTEK dated October 15 and October 26, 2012 and several attachments. (See Appendix 9-1 included at end of this Section.)

9.3. RATA Tests The traditional Part 60 relative accuracy specification for SO2, NOx and most other pollutant gas CEMS is ≤20% of the reference measurement value or ≤10% of the emission standard, whichever is least restrictive. This specification is used for the Holcim project as a tentative specification. The relative accuracy is calculated as the sum of the absolute value of the differences and the 95% confidence coefficient, divided by either the mean reference measurement result or the emission standard, to express the result as a percentage. The emission standard is 3 ppm at 7% O2, dry basis. For the purposes of this comparison, we will simply use 3 ppm HCl as the emission standard. For TDL CEMS, an optical realignment was performed following initial spikes performed on Sept. 17. Also, the software was changed to eliminate negative

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zero value suppression and the method of quantification was changed from peak area to peak height by Keith Mackay of Unisearch. After issues with the HCl cylinder tag values became apparent, Prism re-analyzed the 318 ppm HCl cylinder that was used for the TDL spikes. The Prism re-analysis value was 294 ppm, 7.5% less than the cylinder tag value. The 318 ppm value was ultimately used in the final TDL spike calculations because it was the same value used to establish the site-specific calibration. This is equivalent to the use of the “direct analysis” value for FTIR systems (rather than the tag value) for dynamic spike recovery calculations and also equivalent to the procedure used in the SICK MCS100E spike calculations. Keith Mackay subsequently re-quantified the data reverting to the peak area method and changed in the calibration factor to reflect the analysis of the HCl calibration gas as 318.5 ppm. All data provided on this report is based on the 318.5 ppm reference value and not the 294 ppm re-analysis value determined by Prism.. The re-quantified TDL data submitted on Sept. 21 by Keith Mackay to Holcim were used in all of the subsequent relative accuracy calculations. The original and re-quantified data were included in the measurement results provided by Mackay and generally reflected a decrease in the measured HCl values at higher concentrations. It should be noted that no one at CEMTEK or Unisearch had access to the relative accuracy test data or results prior to the re-quantification of the data by Keith Mackay to use the peak area method.

9.3.1. Two Mills On RATA Tests

The two mills on RATA results are shown in Table 9-1. For this low concentration test, the TDL CEMS relative accuracy was 4.4% of the emission standard. The CEMS meets the RA requirement. The small mean difference of -0.1 ppm is attributed to the fact that the FTIR reference system does not measure values below 0.1 ppm.

9.3.2. Two Mills OFF RATA Tests

The two mills off RATA results for the TDL CEMS are shown in Table 9-2 based on all 18 runs performed. For this high concentration test, the TDL CEMS relative accuracy was 10.2% which meets the 20% relative accuracy specification. The mean difference was -0.90 ppm reflecting that the TDL values were lower than the reference FTIR measurements.

Table 9-1 CEMTEK TDL Two Mills On RATA Calculations

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 18-Sep 9:00 - 9:30 0.02 0.12 -0.10 0.012 18-Sep 10:11 - 10:40 0.07 0.15 -0.08 0.013 18-Sep 11:16-11:46 0.04 0.14 -0.10 0.014 18-Sep 11:47 - 12:17 0.02 0.11 -0.09 0.015 18-Sep 12:18 - 12:48 0.03 0.09 -0.06 0.006 18-Sep 13:19 - 13:48 0.01 0.17 -0.16 0.037 18-Sep 13:50 - 14:19 0.06 0.11 -0.05 0.008 18-Sep 14:21 - 14:50 -0.01 0.10 -0.11 0.019 18-Sep 15:16 - 15:46 -0.01 0.16 -0.17 0.03

SUM 0.23 1.15 -0.92 0.11AVG 0.03 0.13 -0.10 0.01

RATA RESULTSAverage Difference -0.10Standard Deviation 0.04

Confidence Coefficient 0.03 Relative Accuracy % 104%

Relative Accuracy ppm 0.13 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 4.4% % of STD

Table 9-2 CEMTEK TDL Two Mills Off RATA Calculations (18 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 19-Sep 6:58 - 7:26 13.06 13.86 -0.80 0.642 19-Sep 7:28 - 7:58 13.43 14.18 -0.75 0.563 19-Sep 7:59 - 8:29 13.93 14.68 -0.75 0.564 19-Sep 8:38 - 9:07 14.08 15.29 -1.21 1.465 19-Sep 9:09 - 9:39 14.38 15.43 -1.05 1.106 19-Sep 9:40 - 10:10 14.30 15.59 -1.29 1.667 19-Sep 10:16 - 10:47 15.20 16.08 -0.88 0.778 19-Sep 10:47 - 11:16 15.44 16.46 -1.02 1.049 19-Sep 11:16 - 11:46 14.92 16.59 -1.67 2.79

10 19-Sep 11:53 - 12:23 13.91 15.74 -1.83 3.3511 19-Sep 12:24 - 12:54 7.72 8.99 -1.27 1.6112 19-Sep 12:55 - 13:25 5.77 6.40 -0.63 0.4013 19-Sep 13:38 - 14:08 4.40 5.31 -0.91 0.8314 19-Sep 14:09 - 14:39 4.32 4.86 -0.54 0.2915 19-Sep 14:40 - 15:10 4.11 4.61 -0.50 0.2516 19-Sep 15:18 - 15:46 4.01 4.41 -0.40 0.1617 19-Sep 15:58 - 16:18 3.92 4.30 -0.38 0.1418 19-Sep 16:19 - 16:49 3.83 4.12 -0.29 0.08

SUM 180.73 196.90 -16.17 17.72AVG 10.04 10.94 -0.90 0.98

RATA RESULTSAverage Difference -0.90Standard Deviation 0.43

Confidence Coefficient 0.22 t = 2.11Relative Accuracy 10.2%

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The relative accuracy test procedures allow for the rejection of three test runs, as long as nine test runs are reported. The two mills off RATA results were recalculated based on 15 test runs (omitting runs 6, 9, and 10) as shown in Table 9-3. The relative accuracy based on 15 test runs was 9.3% of the reference value.

9.3.3. One Mill On RATA Tests

For this test 17 reference test runs were completed. HCl concentrations began above 3 ppm and decreased throughout the day as lime inject was increased on several occasions. The TDL CEMS relative accuracy was calculated for runs 1-17 and the results were 18.7% of the reference value as shown in Table 9-4. This result meets the 20% relative accuracy specification. The mean difference was -0.06 ppm reflecting that the TDL values were virtually equal to the reference FTIR measurements.

The one mill on RATA results were recalculated based on 14 “best” test runs (omitting runs 1, 5, and 15) as shown in Table 9-5. The relative accuracy based on 14 test runs was 13.6% of the reference value.

9.4. Dynamic Spikes More than 27 dynamic spikes were performed by Jim Peeler during the performance test week. The nominal 318 ppm calibration gas specifically purchased for the evaluation of the TDL should produce about a nominal 5 ppm increase in the response for the TDL. The specific expected response requires inputting the gas concentration and the effluent temperature into the spreadsheet as a correction for absorbance line strength is included in the calculation. The spreadsheet must have the proper effluent measurement path length and the correct audit cell path length. Keith Mackay indicated that the actual cell path length differed from the fixed value in the spreadsheet. After, some investigation, Keith recommended that we make an offsetting correction to the effluent path length (change from 11.12 to 11.61 meters and use the 16.5 mm cell path length as opposed to the correct 15.8 mm cell path length. So doing, the ratio of the cell and effluent path lengths remains the same. The correct value of the cell path length and the

Table 9-3 CEMTEK TDL Two Mills Off RATA Calculations (15 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 19-Sep 6:58 - 7:26 13.06 13.86 -0.80 0.642 19-Sep 7:28 - 7:58 13.43 14.18 -0.75 0.563 19-Sep 7:59 - 8:29 13.93 14.68 -0.75 0.564 19-Sep 8:38 - 9:07 14.08 15.29 -1.21 1.465 19-Sep 9:09 - 9:39 14.38 15.43 -1.05 1.107 19-Sep 10:16 - 10:47 15.20 16.08 -0.88 0.778 19-Sep 10:47 - 11:16 15.44 16.46 -1.02 1.04

11 19-Sep 12:24 - 12:54 7.72 8.99 -1.27 1.6112 19-Sep 12:55 - 13:25 5.77 6.40 -0.63 0.4013 19-Sep 13:38 - 14:08 4.40 5.31 -0.91 0.8314 19-Sep 14:09 - 14:39 4.32 4.86 -0.54 0.2915 19-Sep 14:40 - 15:10 4.11 4.61 -0.50 0.2516 19-Sep 15:18 - 15:46 4.01 4.41 -0.40 0.1617 19-Sep 15:58 - 16:18 3.92 4.30 -0.38 0.1418 19-Sep 16:19 - 16:49 3.83 4.12 -0.29 0.08

SUM 137.60 148.98 -11.38 9.91AVG 9.17 9.93 -0.76 0.66

RATA RESULTSAverage Difference -0.76Standard Deviation 0.30

Confidence Coefficient 0.17 t = 2.145Relative Accuracy 9.3%

Table 9-4 CEMTEK TDL One Mill On RATA Calculations (17 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 20-Sep 8:00 - 8:30 2.56 3.21 -0.65 0.422 20-Sep 8:30 - 9:00 2.21 2.35 -0.14 0.023 20-Sep 9:00-9:30 2.14 2.05 0.09 0.014 20-Sep 9:41-10:11 1.54 1.84 -0.30 0.095 20-Sep 10:12-10:42 1.33 1.66 -0.33 0.116 20-Sep 10:42 - 11:12 1.35 1.53 -0.18 0.037 20-Sep 11:22 - 11:52 1.26 1.44 -0.18 0.038 20-Sep 11:52 - 12:22 1.45 1.35 0.10 0.019 20-Sep 12:22 - 12:52 1.19 1.30 -0.11 0.01

10 20-Sep 13:06 - 13:36 1.05 1.21 -0.16 0.0311 20-Sep 13:36 - 14:06 0.94 1.06 -0.12 0.0112 20-Sep 14:06 - 14:36 0.74 0.85 -0.11 0.0113 20-Sep 15:00 - 15:30 0.36 0.49 -0.13 0.0214 20-Sep 15:30 - 16:00 0.73 0.54 0.19 0.0415 20-Sep 16:00 - 16:30 2.19 1.05 1.14 1.3016 20-Sep 16:59 - 17:29 0.59 0.71 -0.12 0.0117 20-Sep 17:29 - 17:59 0.00 0.07 -0.07 0.0018

SUM 21.63 22.71 -1.08 2.16AVG 1.27 1.34 -0.06 0.13

RATA RESULTSAverage Difference -0.06Standard Deviation 0.36

Confidence Coefficient 0.19 t =2.12Relative Accuracy 18.7%

Relative Accuracy ppm 0.25 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 8.3% % of STD

Table 9-5 CEMTEK TDL One Mill On RATA Calculations (14 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

2 20-Sep 8:30 - 9:00 2.21 2.35 -0.14 0.023 20-Sep 9:00-9:30 2.14 2.05 0.09 0.014 20-Sep 9:41-10:11 1.54 1.84 -0.30 0.096 20-Sep 10:42 - 11:12 1.35 1.53 -0.18 0.037 20-Sep 11:22 - 11:52 1.26 1.44 -0.18 0.038 20-Sep 11:52 - 12:22 1.45 1.35 0.10 0.019 20-Sep 12:22 - 12:52 1.19 1.30 -0.11 0.01

10 20-Sep 13:06 - 13:36 1.05 1.21 -0.16 0.0311 20-Sep 13:36 - 14:06 0.94 1.06 -0.12 0.0112 20-Sep 14:06 - 14:36 0.74 0.85 -0.11 0.0113 20-Sep 15:00 - 15:30 0.36 0.49 -0.13 0.0214 20-Sep 15:30 - 16:00 0.73 0.54 0.19 0.0416 20-Sep 16:59 - 17:29 0.59 0.71 -0.12 0.0117 20-Sep 17:29 - 17:59 0.00 0.07 -0.07 0.0018

SUM 15.55 16.79 -1.24 0.33AVG 1.11 1.20 -0.09 0.02

RATA RESULTSAverage Difference -0.09Standard Deviation 0.13

Confidence Coefficient 0.07 t =2.16Relative Accuracy 13.6%

Relative Accuracy ppm 0.16 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 5.5% % of STD

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validity of the above correction are further supported in the correspondence from CEMTEK dated October 26 included in Appendix 9-1. All of the spike conditions, spike responses, and % Recoveries are shown in Table 9-6. A series of three spikes with the 318 ppm gas were performed with purging of the cell with nitrogen from a compressed gas cylinder between spikes. There was a variation in the spiked responses even though the effluent was consistently at very low HCl levels. Jim Peeler performed three additional spikes of the 318 ppm gas and then several dilutions of the 318 gas, and a few very low concentration spikes during a period while Keith was absent. Again, a decreasing response to the three 318 ppm spike replicates was observed and the response to the low level spike seemed to be erratic, appearing and disappearing. Mackay soon reviewed the data and on the basis of the variable spike responses, adjusted the optical alignment and indicated it has not been locked down. After the adjustment, the repeatability of the dynamic spikes was much improved. Mackay also said that the unusual responses at very low concentrations were due to a negative value suppression feature of the software. Mackay removed this feature so that negative values due to noise around the zero concentration level would be apparent. Because of these changes to the monitoring system, the spikes prior to the changes are labeled as 01, 02 … 08. Afterwards the spikes are labeled in consecutive order for each day they were performed. Replicate analyte spikes were performed with the undiluted standard to provide an assessment of the precision of this determination. Dynamic spikes were also performed by quantitative dilution of the spike gas to lower the spike concentration. Spikes were performed at very low concentrations for the purpose of the LOS determination. Spikes were performed on different days with different background (native HCl concentrations). During several of the RATA tests, it was possible to perform dynamic spikes during the same periods that the reference FTIR system was performing its QA spikes due to the rapid response and recovery of the TDL measurement system. After the alignment adjustment, the 12 dynamic spike responses for the undiluted 318 ppm HCl calibration gas range from 102% to 115% over a wide range of effluent concentrations on three different days. For consecutive spikes conducted over short periods, the spike responses are very consistent. For

Table 9‐6 CEMTEK Unisearch TDL SpikingHCl ppm

Monitor responses were retrieved from EXCEL file "Corrected Data for Cylinder Value" 318 Spike cylinder tagMonitor calibration and spike recoveries based on 318 ppm tag value 294 Spike cylinder Prism re‐analysis

Unisearch  Expected Stable spike response shown in bold spreadhseet Response %Recovery

Calculated  Effluent + IncrementTemp Temp HCl Spiked Spike Gas Increment Comments

Date Spike# Time (start) Time (end) K F ppm Response ppm ppm ppm17‐Sep 01 374 214 0.01 ppm

11:04:19 6.16 318 5.34 5.34 115%11:06:19 0

17‐Sep 02 11:10:40 011:12 11:14 374 214 5.73 318 5.34 5.34 107%

11:16:00 11:17:30 017‐Sep 03

11:20:20 11:22:30 374 214 5.67 318 5.34 5.34 106%

17‐Sep 04 12:11:21 377.7 220 0.006 318 5.4212:14:21 12:17:32 6.58 318 5.423 5.429 121%12:22:32 378.4 222 0.109 5.532 119%12:25:52 0.139

17‐Sep 05 12:27:42 12:28:22 378.7 222 6.27 318 5.43 5.539 113%12:31:02 0.115 5.5712:34 12:37 0.14

17‐Sep 06 12:38:52 12:40:32 378.7 222 5.71 318 5.43 5.5712:48:42 0.04

Manifold flow adjustments for blends17‐Sep 07 13:03:52 13:04:52 377 219 0.54 29.3 0.498 0.498 108% 3.00 lpm N2 and .304 lpm 294 ppm gas

13:09:00 3.08 lpm N2 and .150 lpm 294 ppm gas17‐Sep 08 13:09:53 13:10:23 0.27 14.8 0.252 0.252 107%

Note spikes 01 02 amd 03 show varying (decreasing) responses.  Repeat spikes 04 05 and 06 show same phenomenaKEITH MACKAY ADJUST Optical ALIGNMENT and tighten

Start Over After Optical Alignement Adjustment

17‐Sep 1 13:54:14 13:56:14 372 210 0.001 5.61 318 5.351 5.352 105%17‐Sep 2 14:04:04 14:05:04 371 208 0.01 5.67 318 5.338 5.348 106%17‐Sep 3 14:14:04 14:15:04 370 207 0.015 5.61 318 5.332 5.347 105%

17‐Sep 4 14:37:05 14:38:25 368.9 205 0 2.76 161.5 2.702 2.702 102% 0.43 lpm N2 and .444 lpm 294 ppm gas17‐Sep 5 14:49:06 14:49:56 368.5 204 0 2.67 161.5 2.699 2.699 99% 0.43 lpm N2 and .444 lpm 294 ppm gas

17‐Sep 6 14:56:16 14:57:03 368 203 0 1.575 100.6 1.679 1.679 94% 0.43 lpm N2 and .199 lpm 294 ppm gas17‐Sep 7 15:03:56 15:04:26 368 203 0 1.635 100.6 1.679 1.679 97% 0.43 lpm N2 and .199 lpm 294 ppm gas

17‐Sep 8 15:15:36 15:16:26 368 203 0 0.23 20.0 0.334 0.334 69% 2.92 lpm N2 and .196 lpm 294 ppm gas LOS determination17‐Sep 9 15:23::46 15:24:16 368 203 0 0.29 20.0 0.334 0.334 87% 2.92 lpm N2 and .196 lpm 294 ppm gas  LOS determination

17‐Sep 10 15:27 368 203 0.09 10.7 0.179 0.179 50% 2.92 lpm N2 and .102 lpm 294 ppm gas  LOS determination‐0.005 No spike

Effluent

17‐Sep 11 16:09:19 16:10:49 370 207 0 5.53 318 5.332 5.332 104%17‐Sep 12 16:14:50 16:15:50 370 207 0 5.54 318 5.332 5.332 104%17‐Sep 13 16:20:00 16:22:00 370 207 0 5.55 318 5.332 5.332 104%

19‐Sep 11:47:05 15.61 11:50:25 11:53:45 440 333 22.9 318 6.137 21.737 105% Pre‐spike plus increment

11:55 11:57 16.35 22.49 102% Post‐spike plus increment

20‐Sep 1 7:24 405 270 4.307:27 10.93 318 5.726 10.03 109% Pre‐spike plus increment

20‐Sep 2 7:52 406 271 2.957:56 9.25 318 5.726 8.676 107% Pre‐spike plus increment

20‐Sep 3 9:34:41 407 273 1.8059:37:41 9:38:41 8.56 318 5.745 7.55 113% Pre‐spike plus increment9:40:11 9:41:21 1.7 7.445 115% Post‐spike plus increment

20‐Sep 4 11:14:03 408 275 1.4811:15 4.5 159.0 2.879 4.36 103% 0.450 lpm N2 and .450 lpm 294 ppm gas

12:55:15 12:55:55 408 275 1.0520‐Sep 5 12:56:45 12:57:35 3.97 159.0 2.879 3.929 101% 0.450 lpm N2 and .450 lpm 294 ppm gas

1.1 3.979 100%

85

example, spikes 1, 2, and 3 on Sept. 17 resulted in spike recoveries from 105% to 106%. Spikes 11, 12 and 13 on Sept. 17 all showed spike recoveries of 104%. The spike recoveries are all within acceptable tolerances and the spike procedure and TDL responses appear to be accurate and precise. All six spike results using the diluted 318 ppm gas (i.e., 101 to 161 ppm (31% to 51% of the undiluted 318 ppm gas) produced spike recoveries ranging from 94% to 102%. These results demonstrate that the TDL responses are accurate and precise and that spikes can be performed using small incremental additions. During preliminary discussions with Keith Mackay about on-site observations, there was some concern expressed about the effects due to CO2 broadening which occurs in the stack gases but which are not present in the calibration gas as it does not contain CO2. (A few spikes with 50/50 mixtures of the 294 ppm HCl and 20.1% CO2 were performed on Sept. 25 to provide CEMTEK and Unisearch the opportunity to see if that made any difference. These attempts have not yet provided insight into the issue.) Previous laboratory studies conducted by EPRI suggest little to no effect of CO2 on HCl measurements up to 11% CO2. However, CO2 concentrations at cement plants are significantly greater due to calcination of the limestone. Future laboratory evaluations are being planned to evaluate the effects at higher CO2 concentrations. Degradation of the concentration in the HCl cylinder appears to be a likely possibility, as all of the re-analyzed cylinders tested on Sept. 21 had concentrations lower than the certified values. However, it is expected that if the actual HCl concentration of the spike cylinder was less than the assigned value, that spike recoveries would be lower than 100%.

9.5. Limitation of Detection (LOD) and Limitation of System (LOS) An extensive EPRI laboratory study conducted by the University of California Riverside demonstrated that the LOD for the TDL was 0.66 ppm meters at 100°C and 1.10 ppm meters at 200°C. For the 10.6 meter path length at the St. Genevieve installation, this is equivalent to 0.06 ppm HCl for the effluent temperatures with two mills on, and about 0.08 ppm for the effluent temperatures with two mills off.

86

Field conditions are likely to increase the LOD somewhat as compared to laboratory conditions. A reasonable guestimate to the TDL LOD at the St. Genevieve installation is 0.10 to 0.15 ppm. Successively decreasing spike gas concentrations were introduced to the in-line audit cell by means of diluting the 318 ppm audit gas with nitrogen using the EMI gas dilution manifold. (See spikes 1 through 10 for Sept. 17 in Table 9-6.) The diluted spike concentration of 9.9 ppm is equivalent to an effluent HCl concentration of 0.165 ppm and was clearly distinguishable from the zero HCl concentration response of -0.005 ppm observed for the effluent after the spike was discontinued. Therefore the LOS for the TDL system as installed at St. Genevieve under real world conditions while actively monitoring cement kiln effluent is ≤ 0.16 ppm. Lower concentrations were spiked into the audit cell, however it was difficult to distinguish the presence of the response from the apparent zero value.

Appendix 9A

CEMTEK Correspondence

(pages not numbered)

Continuous Emissions Monitoring CEM Systems, Service, Repair and Parts

888-400-0200 toll free www.cemteks.com info@cemteks.com October 15, 2012 Emission Monitoring, Inc. 8901 Glenwood Avenue Raleigh, NC 27612 Attn: Jim Peeler Subject: Follow-up to the Jim’s Question with regards to Changing the Calibration

Factor for TDL-based Monitors Dear Mr. Peeler,

Thank you for giving CEMTEK Environmental the opportunity to provide our response with regards to changing the calibration factor on TDL-based HCl monitoring systems. The calibration factor is a value/term that accounts for the probability of light absorption of HCl on a molecular level. Also known as the absorption cross section coefficient, it is a key variable of the Beer-Lambert Law. In order to solve the Beer-Lambert Law, this parameter must be known and accounted for. With TDL-based systems, this value is determined at the factory for each analyzer through the use of an audit module with a known value of HCl. Unisearch’s standard HCl reference is a sealed gas cell with HCl gas from a cylinder verified via titration and each analyzer’s calibration factor is adjusted to this reference. However, the Unisearch reference cell was made over 3 years ago, and although no significant variability in the cell concentration has been noted, there exists the possibility that the factory set calibration factor may be incorrect. As a result, the calibration factor should be verified and changed to match with a verified cylinder or external audit cell on site and the data adjusted for the new calibration—this is a part of our procedure during the commissioning of TDL-based HCl monitors. At Holcim, the analyzer’s calibration factor was verified with a 318.5 ppmv bottle provided by Airgas. See below for a summary of the process to revise the calibration factor in the field.

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During the testing conducted at site, the listed 318.5 ppmv bottle originally used to calibrate the instrument was reanalyzed and its new value was determined to be lower than listed on the tag: 294 ppmv. The calibration factor was then re-corrected from 8576 to 6295 in September to account for the change. See the attached Excel spreadsheet that includes the plotted spike tests conducted at Holcim adjusted with the new calibration factor. Please also find attached the documentation that details the background on the calibration factor as well as feedback with regards to the TDL results from your analysis and recommendations to verifying a cylinder’s concentration. In addition, we have provided a summary of the modifications that have been done to the system to improve/test its performance. If you have any questions with regards to the provided documentation, please do not hesitate to contact me at 714-437-7100 ext. 272 or Keith Crabbe at 714-437-7100 ext. 221 or by e-mail at ptran@cemteks.com or keith@cemteks.com. Sincerely,

Paul Tran Project Engineer / TDL Product Manager

Keith Crabbe Engineering Manager

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Calibration Factor Verification done at Holcim during Analyzer Startup on July 13th After having the instrument and optics set up, confirmation of the factory set peak and area calibration factors (CFs) was conducted. The original factory set values are 10800 and 716 respectively. A 318.5 ppmv bottle was employed and began flowing gas at 1-2 L/min at a pressure of 5-10 psig. At the time of measurement, the stack HCl reading was averaging at 3.8 ppmv. With a 318.5 ppmv bottle, the expected concentration per my spreadsheet was 4.4 ppmv. This is incorrect since the inputted flow-thru cell length is 0.124 meters from a previous HCl-TDL installation. The cell used here at Holcim was a bit longer at 0.165 meters as noted on the cell itself. A correction to the path length ratio was applied to correct the discrepancy, which brings up the expected value to 5.9 ppmv. Once this was done, the expected analyzer response was 9.8 ppmv. Corrections to the area measurement were done first. The analyzer was first set up to use the area measurement and measured it for a period of time to obtain a reasonable average (on the order of 5-10 minutes). The analyzer response was 13.8 ppmv, which is 42% high. Taking the inverse of 142% and multiplying it by the original area CF yields 505. The spike test was then re-run to confirm the CF. Analyzer response was 10.0 ppmv; approximately 2% high. The area CF was corrected again to a final value of 493. With the peak measurement, the same procedure applied to the area measurement was conducted. The initial analyzer response with peak measurement was 12.4 ppmv; 27% high. The peak CF value was corrected it to 8474 and the gasses were reran to confirm it. This second test yielded a response of 9.6 ppmv; approximately 1% low. The CF was finally corrected to 8576 as a final value before leaving the site. The analyzer was left to take measurements via area per Keith Mackay's suggestion due to observations of peak broadening due to CO2 interaction.

3041 South Orange Ave, Santa Ana, CA. 92707 Phone: 714-437-7100 Fax: 714-437-7177 2013 S. Wood Avenue, Linden, NJ 07036 Phone: 908-474-9630 Fax: 908-474-9413

Regarding the calibration factor The TDL uses the Beer-Lambert Law to convert a quantity of absorption into a concentration as follows:

L

IIVTC L )ln( 0α−= (1)

Where:

α is the line strength factor at STP I is the amount of measured light after passing through the

gas medium 0I is the amount of initial light (i.e. transmitted light with no

gas present that is to be measured) L is the length of the absorption medium (Path length) V is the volume correction

LT is the line strength correction (a function of gas temperature)

When we do the initial calibration of the instruments we use a certified cylinder of gas, and re-arrange the equation to solve for α . For the set up at Holcim, we noticed that the line shape was significantly broader for the process gas than for our internal reference cell. We believe this is caused by collisional broadening with the other constituents of the process gas. This is not the same as interference caused by another absorption feature, but by the molecules of HCl interacting (colliding) with H2O, CO2, N2, etc in the process. The broadening, if present, may decrease the peak height of the absorption signal while increasing the width. Therefore, the area of the absorption peak will stay constant, independent of the broadening. Since we can’t measure these other gases directly with the TDL and there are no CO2 absorption features in the region we use to measure HCl, we can compensate for these unknowns by measuring the area of the absorption feature, instead of relying on the peak absorption feature. Typically, we measure the peak absorption feature, and the one extremely nice aspect of the peak height is that the system is completely calibration free. The drawback of using the area

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measurement is that we have no way of measuring the wavelength of light we’re emitting, so we must calibrate the instrument when we make a change to the frequency of light we are emitting by increasing, or decreasing the amount of ‘ramping’ we perform. Change of ramp size will alter the absorption signal area, and hence the calibration factor. However, once the area is calibrated against a certain ramp size, the calibration factor will stay constant as long as the ramp size is not changed. See attached document that shows how things change when the ramp is adjusted.

Regarding Confirmation of Gas Bottle Concentration It is recommended that a titration of the gas bottle is conducted in order to confirm the actual concentration in lieu of utilizing a FTIR since the FTIR itself is calibrated to a reference.

Modifications Made to the Analyzer over the Test Period The following modifications have been added to the analyzer to improve its performance or compare to the draft performance specification for this private test:

• Implementation of a residual background measurement to aid in calculating the background when there is HCl present in the gas stream. This was implemented prior to equipment startup at site.

• Implementation of dynamic temperature inputs to analyzer. This employed was to account for the potentially wide swings in temperature at site. The expected error in the measurements would be in the range of 6 to 7% if a fixed temperature of 126.6°C was employed—thus a fixed calibration factor.

• Suppression of negative values that were observed via adjusting the algorithm to provide negatives for obtaining a true zero, but to not fit an inverted absorption spectrum that occasionally occurs.

• Disabling Correlation (R-value) Correction. This feature suppresses low concentration readings when its R-value for the measurement is lower than 0.7 by applying a correction factor based on its R-value. Thus when low values with the function enabled is lower when flowing a very low HCl concentration gas.

3041 South Orange Ave, Santa Ana, CA. 92707 Phone: 714-437-7100 Fax: 714-437-7177 2013 S. Wood Avenue, Linden, NJ 07036 Phone: 908-474-9630 Fax: 908-474-9413

• Implementing the automated calibration gas solenoid assembly in order to test the use of the internal audit cell in comparison to a daily calibration gas injection sequence per EPA’s HCl performance specification.

Continuous Emissions Monitoring CEM Systems, Service, Repair and Parts

888-400-0200 toll free www.cemteks.com info@cemteks.com October 24, 2012 Emission Monitoring, Inc. 8901 Glenwood Avenue Raleigh, NC 27612 Attn: Jim Peeler Subject: Transmittal letter for the comments to the Holcim draft report. Dear Mr. Peeler,

Please find attached our markups to the draft Holcim report. Also below you will find additional information to questions expressed during the testing and correction to our previous statement in regards to the data collected on September 21st. After further review with Unisearch and the data, we need to retract our statement with regards to the calibration factor noted in the previous letter dated October 15, 2012. The calibration factor was not adjusted to reflect the 294 ppmv; rather that it was readjusted to match the bottle concentration of 318.5 ppmv. All data taken and submitted to Holcim, which includes the corrected dataset provided on September 21st by Keith Mackay, reflects this value. It is believed that the cylinder concentration is 318.5 ppmv as the results of the relative accuracy tests you have conducted corroborate with this value. As stated in the previous letter, to confirm the value of the bottle, it is preferred that a pH titration is conducted. Pertinent to the calculated spike results conducted in September, we have a number of comments. The formula employed in calculating the sample spike recoveries (SR) differs from the equation referenced in the draft EPA performance specification reference in section 12.13.2 of the draft Performance Specification 18. Equation 1 is the equation employed in the spiking tests.

BackgroundEffluent Response Spike Expected

ResponseAnalyzer

MMM

SR+

= (1)

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For the number of daily automated spikes we have been conducting for the past week, the sample spike recoveries were calculated as follows:

Response Spike Expected

BackgroundEffluent ResponseAnalyzer

MMM

SR−

= (2)

While Equation 2 also differs from the referenced equation in the draft PS18 specification, section 12.13.2, it is based off of it. Either equation provides similar results. It was also noted that the calculated recoveries ranged from 110% to 140% after Keith’s adjustment of the optical alignment and locking it into place. Prior to the alignment adjustment, the recoveries ranged from 106% to 161%. It is unknown at this time as to why the range of the recoveries is so wide. The number of daily automatic spiking tests that we have been conducting in October shows a tighter range of recoveries: the min/max recovery range of this dataset was 95% to 113%, with a median of 104%. Attached to the letter is a summarized table of the results we have collected thus far. I have also attached a summary of the methodology in acquiring and processing the data. With regards to the purpose of modifying the path length of the analyzer to 11.61 meters instead of the actual 11.12 meters: this is due to a locked cell in the spreadsheet that did not allow us to the change the path length of the flow-thru cell. To account for the discrepancy, the path length of the measurement path was modified instead. Below is the formula used in the spreadsheet to calculate the expected analyzer response to a known HCl concentration with a zero HCl background:

LSMT

TPLPLCC

roombottle

stack

stack

cellbottlespike ×××=

/

(3)

Where spikeC = Expected concentration of gas spike response in ppmv bottleC = Concentration of gas cylinder in ppmv cellPL = Path length of flow-thru gas cell in meters stackPL = Path length of stack in meters stackT = Temperature of stack in Kelvin roombottleT / = Temperature of bottle/room in Kelvin LSM = Line strength multiplier Since cellPL was incorrect in the spreadsheet, a correction was applied to stackPL to provide the equivalent and correct data for the measurements. The value for the equivalent stackPL of 11.61 meters was determined as follows:

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meters 61.11meters 158.0

meters 165.0meters 12.11

meters 165.0meters 12.11meters 158.0

,

,

,

,

,

,

=

×=

=

=

adjustedstack

adjustedstack

adjustedstack

incorrectcell

correctstack

correctcell

PL

PL

PLPL

PLPL

(4)

Please see link found in the footnote for a description of how the supplier “calculates” the length of the cell1

. Unisearch opened up the enclosure and measured the internal cell. The path that the gas fills was measured to be 0.158 m, NOT 0.165 m as specified. Looking over the specification sheet from Wavelength References, the path length of the cell is not listed, other than in the description of the item.

Unisearch contacted the manufacturer and they are under the impression that they are 0.165 m in length; their supplier is supposed to be cutting them to 0.165 ± 0.001 m, so there is a breakdown [in communication] somewhere. As far as the gentleman that Unisearch talked to knows, this information is not documented but he is checking into it. Figure 1: Measuring the flow-thru gas cell from interior window surface to interior window surface

The information is not documented but they will be including the cell length on the specification sheets from now on. He subsequently tested the 10 other cells they have in stock, all were between 16.3 and 16.6 cm, so I’m not sure why Unisearch received one with such a discrepancy. With regards to the data that was submitted in the previous letter, the data provided on the previous letter is to show how the Correlation Correction function suppresses low concentration measurements where the correction value is less than 0.7. Given the path length of the system, disabling this function improves the measurements near the detection limit. The data to utilize for the report is the set provided to you in September. 1 http://www.wavelengthreferences.com/products/absorption-tubes/

3041 South Orange Ave, Santa Ana, CA. 92707 Phone: 714-437-7100 Fax: 714-437-7177 2013 S. Wood Avenue, Linden, NJ 07036 Phone: 908-474-9630 Fax: 908-474-9413

If you have any questions with regards to the above, please do not hesitate to contact me at 714-437-7100 ext. 272 or Keith Crabbe at 714-437-7100 ext. 221 or by e-mail at ptran@cemteks.com or keith@cemteks.com. Sincerely,

Paul Tran Project Engineer / TDL Product Manager

Keith Crabbe Engineering Manager

Daily Spiking Summary

Day Date # Of readings

Pre-Spike Bkg Average (ppm)

Post-Spike Bkg Average (ppm)

HCl Baseline (ppm)

Average Analyzer Response (ppm)

Average Analyzer Spike Reponse (ppm)

Tavg (K)

Expected Response at Tavg (ppm)

SRavg (%)

SAavg (%)

Cal. Drift

0.0 10/16 13 0.00062 -0.00064 -0.00001 5.322 5.322 357.22 5.195 102.45% 3.44% 0.42% 0.1 10/16 13 -0.00032 -0.00040 -0.00036 4.959 4.959 359.12 5.215 95.08% 3.18% 0.85% 0.2 10/16 13 0.00053 0.00000 0.00027 5.455 5.455 386.72 5.522 98.79% 3.30% 0.22% 0.3 10/16 13 0.00286 0.00002 0.00144 5.847 5.846 383.50 5.486 106.57% 3.57% 1.20% 1.0 10/17 13 5.29874 5.60349 5.45112 11.888 6.437 442.42 6.170 104.31% 3.63% 0.89% 2.0 10/18 13 -0.00017 -0.00051 -0.00034 5.585 5.585 372.74 5.366 104.09% 3.48% 0.73% 3.0 10/19 13 -0.00018 -0.00023 -0.00021 5.640 5.640 376.29 5.405 104.35% 3.49% 0.78% 4.0 10/20 13 -0.00092 -0.00118 -0.00105 5.596 5.597 376.75 5.410 103.46% 3.46% 0.62% 5.0 10/21 13 -0.01857 -0.00504 -0.01180 5.277 5.289 362.12 5.248 100.77% 3.37% 0.14% 6.0 10/22 13 0.56555 0.35426 0.45991 7.136 6.676 419.30 5.896 113.24% 3.79% 2.60% 7.0 10/23 13 0.00342 0.00412 0.00377 5.787 5.783 373.52 5.374 107.61% 3.60% 1.36% 8.0 10/24 13 0.00009 0.00126 0.00068 5.778 5.778 378.99 5.435 106.30% 3.56% 1.14%

MISC Parameters

Bottle Concentration SPAN Ref/Room Temp PLCell PLStack t-value

318.5 30 73 0.158 11.12 n-1 ppm ppm °F meters meters 12

295.9 t-value @ n-1 = 12 K 2.179

Spiking Sequence 1. Start Sequence 2. Inject N2 gas to flow-thru cell 3. Measure pre-spike background levels for 2 minutes.

Generate an average and store. 4. 1 minute delay 5. Stop N2 gas injection 6. Begin HCl gas injection 7. 1 minute delay 8. Measure initial HCl reading and temperature. Store. 9. Record HCl measurements and stack temperature

temporarily 10. After 3 minutes of injection and 2 minutes after initial

reading, take a second reading of HCl and stack temperature.

11. Calculate the percent change in relation to the initial HCl reading. If the change is less than 5%, calculate the average, standard deviation, and number of individual HCl/temperature measurements between the two readings of HCl as done in steps 5 and 7.

a. If this criteria fails i. Stop sequence and return to Step 2. Flow for

at least 2 minutes to purge cell prior to moving to step 3.

12. 1 minute after step 8, stop injection of HCl 13. Begin N2 gas flow to purge the line. 14. 1 minute delay 15. Measure post-spike background levels for 2 minutes.

Generate and average and store. 16. Calculate average background levels using values obtained

from Step 3 and 15. Store. 17. Subtract calculated background level on Step 16 from

calculated average on Step 11. Store 18. Calculate expected analyzer spike response based on the

user-inputted bottle concentration, user-inputted path length, and average temperature calculated in Step 11.

19. Calculate the SA per specification. If the calculated SA is less than or equal to 20%, flag result as a pass. Otherwise flag as a fail.

3041 South Orange Ave, Santa Ana, CA. 92707 Phone: 714-437-7100 Fax: 714-437-7177 2013 S. Wood Avenue, Linden, NJ 07036 Phone: 908-474-9630 Fax: 908-474-9413

20. Calculate the SR per specification. If the calculated SR is less than 15%, flag result as a pass. Otherwise flag as a fail.

Notes: 1. Percent difference is calculated in relation to the initial

recorded value 2. Percent difference calculation was not done for zero /

background measurements as they will consistently fail the criteria unless the percent change is in relation to span

3. The number of measurements between the two readings needs to be greater than or equal to 6 per specification

87

10. SICK MCS100E Results and Observations 10.1. Description

The MCS100E is a straight extractive hot wet monitoring system capable of measurement of multiple parameters using its infrared analyzer, which reports measurements on a dry basis. The main stack are configured to measure SO2, NO, CO, CO2 and H2O for regulatory purposes and to measure NH3 and HCl for Holcim’s internal purposes. An additional measurement channel has been added to facilitate measurement of methane concentrations (CH4) in order to compensate SO2 measurement data for methane interference which creates a positive (high) bias. The various channels of the MCS100EE analyzer rely on either differential absorption or gas filter correlation as analytical principals. Gas samples are acquired through a stainless steel sample probe (stinger) at a sampling point approximately 1 meter from the stack wall. A heated out of stack fine PM filter is included in the probe assembly. Provisions are included to introduce calibration gases upstream of the PM filter for periodic performance audits of the CEMS and calibration/diagnostic tests. Gas samples exiting the probe assembly are conveyed to the MCS 100 system via heated Teflon sample line maintained at 200°C and sample flow rate is maintained by a heated head K&F diaphragm pump maintained at 205°C. The sample gas stream exiting the sample pump enters the folded path analytical cell within the MCS 100 analyzer which is also maintained at 200°C. Analysis of the multiple components is performed by the analyzer by sequentially rotating various interference filters and gas cells into the light path in an appropriate sequence. Routine upscale calibration checks are performed using internal calibration gas cells and/or optical filters located within the analyzer. The HCl monitoring channel is set up on a 0-60 ppm range.

10.2. MCS100E Status

The MCS100E was installed by FLS during the construction of the kiln system and has served as the CEMS for monitoring requirements in the plants Title V Permit for SO2, NOx, CO, and the EPA Part 98 Mandatory Greenhouse Gas Reporting Requirements for CO2. The HCl and NH3 monitoring capabilities are used for Holcim’s internal purposes and are not subject to the QA requirements or activities that apply to SO2, NOx and CO monitoring parameters.

88

An inspection and preventive maintenance for the MCS100E on the kiln system stack was performed by SICK representatives on Aug. 8-9, 2012. The activities performed included verification of the water absorption tables for the MCS100E using a water vapor generator, checks of the calibration response relative to internal gas cells for HCl, cleaning of sample lines and rebuild of sample pump and other preventive maintenance. Injections of HCl standards generated by a Hovocal or similar device were not performed. SICK representatives reported that the MCS100E was in very good condition, had drifted little since its initial calibration in Germany, and was in proper condition for upcoming performance tests. After the spiking tests were performed on the first day of the performance test, it was observed that a calibration of factor of 1.167 was present in the SICK MCS100E HCl channel. (All recorded measurement results are increased by this multiplicative factor.) The origin of this factor could not be determined. After some discussion, it was determined by SICK that the factor should not have been present. Data for the RATA tests were subsequently mathematically adjusted to remove the influence of the factor. Dynamic spike results are unaffected due to the specific procedures used. The dry calibration gas analysis results are adjusted to account for the factor.

10.3. RATA Tests The traditional Part 60 relative accuracy specification for SO2, NOx and most other pollutant gas CEMS is ≤20% of the reference measurement value or ≤10% of the emission standard, whichever is least restrictive. This specification is used for the Holcim project as a tentative specification. The relative accuracy is calculated as the sum of the absolute value of the differences and the 95% confidence coefficient, divided by either the mean reference measurement result or the emission standard, to express the result as a percentage. The emission standard in Subpart LLL for cement plants is 3 ppm at 7% O2, dry basis. For the purposes of this comparison, we will simply use 3 ppm HCl as the emission standard.

89

10.3.1. Two Mills On RATA Tests

The two mills on RATA results are shown in Table 10-1. For this low concentration test, the MCS100E CEMS relative accuracy was 27.7% of the emission standard. The CEMS does not meet the RA requirement, primarily because of the +0.77 ppm average mean difference (CEMS measurements are greater than the reference measurements).

10.3.2. Two Mills OFF RATA Tests

The two mills off RATA results for the MCS100E CEMS are shown in Table 10-2. Run 4 was excluded because the routine automatic O2 calibration occurred during this time period. For this high concentration test, the MCS100E CEMS relative accuracy was 3.1% based on 17 test runs, which is very good.

10.3.3. One Mill On RATA Tests

For this test, 17 reference test runs were completed. HCl concentrations began above 3 ppm and decreased throughout the day as lime injection was increased on several occasions. The MCS100E CEMS relative accuracy was calculated for runs 1-17 and the results were 62% of the reference value and 27.5% of the emission standard as shown in Table 10-3. The CEMS does not meet the RA requirement, primarily because of the +0.69 ppm average mean difference (CEMS measurements are greater than the reference measurements).

The MCS100E CEMS relative accuracy was re-calculated for the last nine runs at lower concentrations. The results were 105% of the reference value and 28.3% of the emission standard for Runs 9-17, as shown in Table 10-4. The CEMS does not meet the RA requirement, primarily because of the +0.75 average mean difference.

10.4. Dynamic Spikes Each equipment supplier was asked to provide a written dynamic spike procedure appropriate for its measurement system because it is very likely that such procedures will be included in the EPA performance specification/QA procedures. This was communicated to SICK on several occasions.

Table 10-1 SICK MCS100 Two Mills On RATA Calculations

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 18-Sep 9:00 - 9:30 0.89 0.12 0.77 0.592 18-Sep 10:11 - 10:40 0.96 0.15 0.81 0.663 18-Sep 11:16-11:46 1.00 0.14 0.86 0.744 18-Sep 11:47 - 12:17 0.98 0.11 0.87 0.765 18-Sep 12:18 - 12:48 0.94 0.09 0.85 0.726 18-Sep 13:19 - 13:48 0.88 0.17 0.71 0.507 18-Sep 13:50 - 14:19 0.81 0.11 0.70 0.498 18-Sep 14:21 - 14:50 0.80 0.10 0.70 0.499 18-Sep 15:16 - 15:46 0.80 0.16 0.64 0.41

SUM 8.06 1.15 6.91 5.36AVG 0.90 0.13 0.77 0.60

RATA RESULTSAverage Difference 0.77Standard Deviation 0.08

Confidence Coefficient 0.06 Relative Accuracy % 651%

Relative Accuracy ppm 0.83 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 27.7% % of STD

Table 10-2 SICK MCS100 Two Mills Off RATA Calculations

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 19-Sep 6:58 - 7:26 12.66 13.86 -1.20 1.442 19-Sep 7:28 - 7:58 14.84 14.18 0.66 0.443 19-Sep 7:59 - 8:29 15.06 14.68 0.38 0.145 19-Sep 9:09 - 9:39 15.89 15.43 0.46 0.216 19-Sep 9:40 - 10:10 15.98 15.59 0.39 0.157 19-Sep 10:16 - 10:47 16.47 16.08 0.39 0.158 19-Sep 10:47 - 11:16 16.82 16.46 0.36 0.139 19-Sep 11:16 - 11:46 16.75 16.59 0.16 0.03

10 19-Sep 11:53 - 12:23 15.82 15.74 0.08 0.0111 19-Sep 12:24 - 12:54 8.94 8.99 -0.05 0.0012 19-Sep 12:55 - 13:25 6.37 6.40 -0.03 0.0013 19-Sep 13:38 - 14:08 5.23 5.31 -0.08 0.0114 19-Sep 14:09 - 14:39 4.90 4.86 0.04 0.0015 19-Sep 14:40 - 15:10 4.61 4.61 0.00 0.0016 19-Sep 15:18 - 15:46 4.50 4.41 0.09 0.0117 19-Sep 15:58 - 16:18 4.51 4.30 0.21 0.0418 19-Sep 16:19 - 16:49 4.35 4.12 0.23 0.05

SUM 183.70 181.61 2.09 2.81AVG 10.81 10.68 0.12 0.17

RATA RESULTSAverage Difference 0.12Standard Deviation 0.40

Confidence Coefficient 0.21 t = 2.12Relative Accuracy 3.1%

Table 10-3 SICK MCS100 One Mill On RATA Calculations (17 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

1 20-Sep 8:00 - 8:30 3.51 3.21 0.30 0.092 20-Sep 8:30 - 9:00 2.18 2.35 -0.17 0.033 20-Sep 9:00-9:30 2.76 2.05 0.71 0.504 20-Sep 9:41-10:11 2.61 1.84 0.77 0.595 20-Sep 10:12-10:42 2.52 1.66 0.86 0.746 20-Sep 10:42 - 11:12 2.37 1.53 0.84 0.717 20-Sep 11:22 - 11:52 2.26 1.44 0.82 0.678 20-Sep 11:52 - 12:22 2.15 1.35 0.80 0.649 20-Sep 12:22 - 12:52 2.17 1.30 0.87 0.76

10 20-Sep 13:06 - 13:36 2.09 1.21 0.88 0.7711 20-Sep 13:36 - 14:06 1.86 1.06 0.80 0.6412 20-Sep 14:06 - 14:36 1.67 0.85 0.82 0.6713 20-Sep 15:00 - 15:30 1.27 0.49 0.78 0.6114 20-Sep 15:30 - 16:00 1.34 0.54 0.80 0.6415 20-Sep 16:00 - 16:30 1.77 1.05 0.72 0.5216 20-Sep 16:59 - 17:29 1.25 0.71 0.54 0.2917 20-Sep 17:29 - 17:59 0.61 0.07 0.54 0.2918

SUM 34.39 22.71 11.68 9.17AVG 2.02 1.34 0.69 0.54

RATA RESULTSAverage Difference 0.69Standard Deviation 0.27

Confidence Coefficient 0.14 t =2.12Relative Accuracy 62%

Relative Accuracy ppm 0.82 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 27.5% % of STD

Table 10-4 SICK MCS100 One Mill On RATA Calculations (Last 9 Runs)

Run Date Time CEMS (ppmw) Ref (ppmw) Difference Difference 2

9 20-Sep 12:22 - 12:52 2.17 1.30 0.87 0.7610 20-Sep 13:06 - 13:36 2.09 1.21 0.88 0.7711 20-Sep 13:36 - 14:06 1.86 1.06 0.80 0.6412 20-Sep 14:06 - 14:36 1.67 0.85 0.82 0.6713 20-Sep 15:00 - 15:30 1.27 0.49 0.78 0.6114 20-Sep 15:30 - 16:00 1.34 0.54 0.80 0.6415 20-Sep 16:00 - 16:30 1.77 1.05 0.72 0.5216 20-Sep 16:59 - 17:29 1.25 0.71 0.54 0.2917 20-Sep 17:29 - 17:59 0.61 0.07 0.54 0.29

SUM 14.03 7.28 6.75 5.19AVG 1.56 0.81 0.75 0.58

RATA RESULTSAverage Difference 0.75Standard Deviation 0.13

Confidence Coefficient 0.10Relative Accuracy 105%

Relative Accuracy ppm 0.85 ppmEmiswsion Standard 3 ppm

Relative Accuracy % of STD 28.3% % of STD

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The MCS100E as configured at the St. Genevieve plant cannot measure SF6 nor can it measure N2O. Furthermore, all of the available eight measurement channels are used for other purposes. Therefore in the absence of any other procedure, Jim Peeler provided an EMI Hovocal for external control of spike gas flow rates and asked that the SICK representative together with Rodney Miller implement an HCl dynamic spike procedure which quantifies the spike rate based on the apparent reduction in other measured gas constituents. The following procedures were used on the first day of the performance test:

• Connect the Holcim MCS100E HCl audit gas (nominal tag value of 33 ppm) to the Hovacal gas inlet and connect the outlet to the MCS gas injection port to the directional valve (probe or cell) located in the lower section of the MCS cabinet. The valve is set in the probe calibrate position.

• Inject the spike gas at rates approximating the expected sample flow rate and observe the responses of CO2, H2O and O2 channels (expected to be most stable parameters for the kiln system effluent).

• Vary the spike gas injection rate by adjusting the Hovocal mass flow meter in iterative steps to find the lowest spike gas injection rate that excludes effluent gas from entering the probe (i.e., CO2, H2O, and O2 concentrations are very near zero). The spike gas injection should continue for a sufficient period to obtain a steady state HCl response. (The iterative procedure took about one-hour to complete and the Hovocal flow reading was about 8 liters per minute when the other measurement parameters were approximately zero. The MCS100E response to the HCl audit cylinder was 30.5 ppm.)

• Turn off the Hovocal and allow the MCS100E to recover to normal effluent monitoring conditions.

• Set the Hovocal spike gas injection rate to 10% of the apparent flow rate (0.8 liters/min) to achieve an approximate 10% spike.

• Record the native effluent concentrations of HCl, CO2, H2O, and O2, inject a 10% spike, record the stable spike gas concentrations, stop the spike, and record the stable native gas concentrations.

• Repeat several times. The actual spike gas dilution rate (i.e., 1 -%spike/100) can be determined from the ratio of the spiked to un-spiked CO2 concentrations. This rate can also be determined from the ratio of the spiked to un-spiked H2O concentrations, or ratio of the spiked to un-spiked O2 concentrations. Knowing the spike gas flow

95

rate, the HCl concentration expected for each spike can be determined from (a) the MCS100E response to the undiluted audit gas (this avoids the problems with using the tag value), and (b) the native pre- or post-test HCl concentration. The spike recovery (%R) is then simply the observed HCl spike response divided by the expected HCl concentration, expressed as a percentage. Table 10-5 presents the MCS 100 spike result calculations for the tests performed on Sept. 17. The spike % recovery is calculated based on CO2, H2O, and O2 reductions for comparison purposes. In addition, the spike recoveries are calculated based on the pre-spike concentration compared to the spiked response, as well as the post-spike concentration as compared to the spiked response. Twenty seven determinations of the %spike recovery were calculated for the 5 spike replicates. Overall, the CO2 calculations seem to provide the most consistent results. The nine replicated spike recoveries for the Sept. 17 spike experiments were all within 92% to 110% based on the CO2 calculations. Jim Peeler conducted additional dynamic spikes on Sept. 21 using an HCl spike gas with a 101 ppm tag value. The spike gas concentration exceeds the MCS100E HCl measurement range (0-60 ppm), so it could not be analyzed directly by the MCS100E. (Also, we did not want to introduce such a high concentration to the measurement system.) Because of problems with the cylinder tag values, the Prism re-analysis of this cylinder was used as the actual concentration. The Prism analysis of CC-85129 was 81.0 ppm. This value was corrected by the MCS100E 1.167 HCl correction factor so that it is on the same basis as the native and spike responses. Hence, the value used in the spike calculations is 94.5 ppm (=81 ppm x 1.167). Other than the above steps to adjust the spike gas concentration value, the dynamic spikes were performed using the same procedure as on Sept. 17. Three replicate spikes were performed at a nominal 10% spike rate and one spike was performed at a nominal 5% spike rate. Table 10-6 presents the calculations and spike results for tests performed on September 21. For the 10% spikes, the individual spike rate determinations based on the pre- and post-test spikes are fairly consistent but the spike recoveries are quite variable (%R ranging over about 20% for each parameter.) The average of the

Table 10‐5 Sept. 17 SICK MCS100 Dynamic SpikesData Recorded by Rodney Miller, Holcim and Steen Jensen, SICKRaw Data

Time HCl CO2 H20 O21:29 0.93 22.90 15.10 9.081:36 3.73 20.58 14.13 8.001:42 0.77 23.13 15.70 8.961:48 4.00 20.68 14.18 8.021:54 0.92 22.96 15.47 9.152:00 4.05 20.50 13.97 8.032:06 0.78 23.21 15.51 8.932:12 4.21 20.81 14.14 7.892:19 0.82 23.25 15.60 8.972:25 3.99 20.92 14.12 7.86

Native, spike responses, and spike gas values all based on uncorrected MCS responses for 1.167 correction factorValues in red are based on pre‐spike native and spikeValues in blue are based on spike and post spike nativeSpikes on 9/17

CO2 Apparent  CO2 CO2 H2O Apparent  H2O H2O O2 Apparent  O2 O2Time HCl CO2 1‐% Spike/100 Ce %R H20 1‐% Spike/100 Ce %R O2 1‐% Spike/100 Ce %R

Native 1:29 0.93 22.90 15.10 9.080.90 3.92 0.95 0.94 2.82 1.32 0.88 4.44 0.84

Spike 1:36 3.73 20.58 14.13 8.000.89 4.04 0.92 0.90 3.73 1.00 0.89 3.94 0.95

Native 1:42 0.77 23.13 15.70 8.960.89 3.91 1.02 0.90 3.64 1.10 0.90 3.88 1.03

Spike 1:48 4.00 20.68 14.18 8.020.90 3.85 1.04 0.92 3.38 1.18 0.88 4.56 0.88

Native 1:54 0.92 22.96 15.47 9.150.89 4.08 0.99 0.90 3.78 1.07 0.88 4.53 0.89

Spike 2:00 4.05 20.50 13.97 8.030.88 4.24 0.96 0.90 3.72 1.09 0.90 3.77 1.08

Native 2:06 0.78 23.21 15.51 8.930.90 3.84 1.10 0.91 3.40 1.24 0.88 4.23 1.00

Spike 2:12 4.21 20.81 14.14 7.890.90 3.92 1.07 0.91 2.85 1.48 0.88 4.38 0.96

Native 2:19 0.82 23.25 15.60 8.970.90 3.78 1.05 0.91 3.63 1.10 0.88 4.48 0.89

Spike 2:25 3.99 20.92 14.12 7.860.8945 0.9092 0.8846

Table 10‐6 Sept. 21 SICK MCS100 Dynamic SpikesData Recorded by Jim Peeler, EMINative and spike responses all based on uncorrected MCS responses for 1.167 correction factorNominal 100 ppm calibration gas was reanalyzed by Prism and found to be 81 ppmEquivalent Spike gs corrected for MCS100 correction factor is 94.5 ppmValues in red are based on pre‐spike native and spikeValues in blue are based on spike and post spike nativeSpikes on 9/21

CO2 Apparent  CO2 CO2 H2O Apparent  H2O H2O O2 Apparent  O2 O2Time HCl CO2 1‐% Spike/100 Ce %R H20 1‐% Spike/100 Ce %R O2 1‐% Spike/100 Ce %R

Native 2:20 1.40 23.70 15.10 8.680.90 11.06 1.01 0.89 11.88 0.94 0.88 12.88 0.87

Spike 2:32 11.20 21.24 13.40 7.610.92 8.82 1.27 0.89 11.04 1.01 0.89 11.75 0.95

Native 2:41 1.20 23.13 14.98 8.580.90 10.15 1.15 0.90 10.48 1.12 0.90 10.66 1.10

Spike 2:57 11.70 20.91 13.49 7.710.89 11.23 1.04 0.89 11.24 1.04 0.89 11.54 1.01

Native 3:12 1.00 23.48 15.15 8.690.90 10.48 1.12 0.90 10.57 1.11 0.88 12.30 0.95

Spike 3:27 11.70 21.10 13.60 7.64

5% spike 3:36 6.30 22.23 14.29 8.080.95 5.92 1.06 0.96 4.94 1.28 0.92 9.02 0.70

Native 3:45 1.30 23.39 14.87 8.81

Average Values 0.9015 1.1184 0.8941 1.0443 0.8857 0.9771

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five calculations of percent recoveries are: 112% for CO2, 104% for H2O, and 98% for O2. All of these results indicate acceptable performance of the MCS100E, but show that the spike procedure does not provide very consistent results. The results for the single at the 5% injection rate are less consistent, which is attributed to insufficient change in the native concentration at the lower spike rate.

10.5. Compressed Gas Cylinder Analysis At the outset of the performance test, the SICK representative expressed concerns that it would not be possible to achieve stable MCS100E responses to dry calibration gases without exhausting the cylinder. However, a stable response to the Paxair audit cylinder was obtained during the pre-spike sample gas flow rate determination on Sept. 17. Jim Peeler injected nominal 10 ppm and 5 ppm cylinders on Sept. 21 with Rodney Miller’s assistance. It is necessary to adjust the gas flow rate to match the normal effluent sampling rate, because an isolation valve closes in the probe when calibration gas are introduced at the probe. (This is not a “probe flood: calibration.) The following results were obtained:

Table 10-7 Dry Calibration Gas Analysis Tag value

(ppm) Prism Analysis

(ppm) MCS100E raw

(ppm) MCS100E/1.167

(ppm) Error (ppm)

33.1 25.5 30.3 25.7 0.2 10 8.85 10.1 8.65 -0.20 5 4.07 4.94 4.23 0.16

A graph showing the response of the MCS to a nominal 10 ppm HCl calibration gas is shown in Fig 10-1. The MCS100E HCl measurement results for gases introduced at the sample probe agree very well with Prism’s analysis of the same cylinders.

10.6. Limitation of Detection (LOD) and Limitation of System (LOS)

The minimum measurement range in the MCS100E literature is 0-10 ppm.

0.00

2.00

4.00

6.00

8.00

10.00

12.00

14.00

16.00

18.00

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

ppm

HCl

Tn=mie - Minutes

MCS100 Response to 10 ppm Cal Gas

100

Review of the TÜV certification reports provides a 3σ LOD of 0.051 and 0.173 mg/m3 for HCl in dry gas for the two instruments tested. This corresponds to 0.03 ppm and 0.11 ppm, for the two instruments. The LOD can be calculated from dry zero gas injections as three times the standard deviation of the noise. For the St. Genevieve MCS100E, SICK points to data from Aug 9, 9:10 to 9:30 hours where the HCl mean value is 1.4 ppm and the standard deviation of the HCl values is 0.129ppm. The LOD calculated as 3σ is .387 ppm for this period. The data show that the moisture content changed from about 3% to essentially zero during this determination and that the indicated HCl concentration appears to vary with the moisture content. This data is not understood as of the writing of this report. The same calculation can be performed for humidified gas that does not contain HCl. EMI requested identification of the periods during the SICK inspection visit during which dry zero gas and water calibrations were performed in order to perform the LOD calculations. During some of those periods, the HCl channel recorded responses far from zero. There is not sufficient information to correctly interpret this data. During the two mills on RATA, the effluent HCl concentration was 0.15 ppm or less, as determined by the reference system. The MCS100E indicated an average value of 0.9 ppm for the nine runs. It is believed that the elevated response is at least in part due to an analytical interference or cross sensitivity. For the system and analysis as currently configured, the value 0.9 ppm can be used as the LOS for the measurements on kiln system effluent at the St. Genevieve plant. Negative HCl measurements are observed during the O2 upscale calibration checks and soon after usually around -.04 to to-.20, but occasionally as large as -1.3 ppm. The reason for these values is not known but inappropriate cross component compensation is suggested. These negative data appear to be the artifact of the calibration check procedure and should not be included in averages as valid measurements.

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11. HCl Calibration Gas Re-Analysis Calibration gases were obtained from Linde and from AirGas for this project. The gases purchased included analyte spike gases containing nominal 100 ppm and 25 ppm HCl concentrations with nominal tracer gas concentrations of 5 ppm SF6, and 350 ppm N2O in certain cylinders intended for use with the ABB FTIR. 10 ppm HCl cylinders were acquired for performing daily calibration checks. 5 ppm HCl cylinders were also acquired to be used for linearity checks. A nominal 350 ppm HCl gas was requested for incremental calibration checks of the TDL CEMS. In addition, a gas blend containing certified concentrations of SO2, NO, and CO was acquired for both of the FTIR CEMS and other cylinders containing CO2 and NH3 were also purchased. Another HCl gas cylinder supplied by Praxair to St. Genevieve for internal audits of the SICK MCS100E CEMS having a certified HCl concentration of 33.1 ppm was also used during the study and re-analyzed on-site. Most of the HCl cylinders had tag values with certified analysis accuracy (or uncertainty) stated as 5% HCl and 5% SF6. Some cylinders had certified values stated to 2%. During the two months period beginning from the receipt of calibration gases in mid-July until the test week in mid-September, there were multiple occasions when Thermo Fisher Scientific and ABB personnel questioned the tag values of various cylinders or simply stated the tag values were wrong. Because the actual HCl concentrations of the cylinders are critical to determination of whether the CEMS could meet draft EPA performance specifications, it was part of the test plan from the outset that the cylinders would be re-analyzed on-site by Prism using the same FTIR analyzer for the analysis of multiple HCl calibration gases from multiple suppliers. A total of 10 HCl regulators were purchased from AirGas. It was intended that pristine regulators would be installed on HCl cylinders and would remain in place until the cylinder was nearly empty. It was communicated to all parties that cylinders were to be removed from service with at least 250-300 psig remaining, so that re-analysis could be performed before reaching the minimum pressure limitation. Nevertheless, some cylinders were exhausted due to leaks, remote activation of calibrations, or other problems. Cylinders with significantly less than 200 psig could not be reanalyzed. Phil Kauppi of Prism reanalyzed several cylinders during the test week and reanalyzed as many other HCl cylinders as was possible on Sept. 21, the day after the RATA testing was completed. The cylinders were brought into the CEMS shelter where the reference FTIR was located for the entire test week. Care was taken to purge regulators with nitrogen

102

or other dry gas before initial use. Care was taken to properly install the cylinder regulator and purge the contents though a short Teflon line prior to direct connection to the FTIR analyzer. Sufficient time was allowed to acquire a stable response. In some cases this was a very long period. It was also noted that some cylinder valves for brand new cylinders received the day of the reanalysis, had visible corrosion present when the plastic wrapper was removed. The results of Prism’s reanalysis of 25 cylinders performed during the test week are shown in Table 11-1. The results demonstrate gross differences between the certified tag values and Prism’s reanalysis. The difference in the Prism analysis and the tag value ranged from 12% to as much as 70% for 21 of the 25 cylinders. Only two cylinders had a tag value less than 5% different from Prism’s re-analysis and both of these cylinders were nominal 25 ppm mixtures provided by Linde. Linde gas cylinder CC88663 had a certified value 3% greater than the Prism analysis and Linde cylinder CC18123 had a certified value 5% greater than the Prism analysis. It is particularly noteworthy that both of these cylinders have a certification date of Sept. 18, only three days prior to Prism’s on-site analysis! Only two other cylinders had a tag value less than 10% different from Prism’s re-analysis and one of these was another nominal 25 ppm mixtures provided by Linde, and the special high concentration (i.e., 318.5 ppm) HCl calibration gas used for audits of the cross-stack TDL. All eight of the other AirGas cylinders (excluding the special high concentration gas) that were reanalyzed have certified values which differ from the Prism re-analysis by 19% to 44% (average difference of 26.5%). The accuracy of the nominal 5 and 10 ppm gases is of particular concern because these gases are used exclusively for calibration checks (i.e., calibration error and linearity tests) as compared to the nominal 25 and 100 ppm gases which are used for dynamic spikes. (Dynamic spikes can be performed without using the “certified tag value” by comparing the results of direct analysis of the undiluted spike gas with the results of the diluted spike gas to assess sample transport and analysis, as is discussed elsewhere in this report.) For the seven nominal 10 ppm calibration gases ( after excluding those certified only three days before the Prism re-analysis), the certified values relative to the Prism analysis differences ranged from 21% to 48% (average difference of 32%). There were only three nominal 5 ppm gases (after excluding those certified only three days before the Prism re-analysis). The certified values relative to the Prism analysis differences were 25%, 25% and 70%. In every single case, the Prism re-analysis results are lower than the certified values.

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Throughout the monitor-specific results section of this report, the analysis of many of the gases analyzed by the Thermo Scientific OMNI FTIR CEMS, the ABB ACF-NT FTIR CEMS, and a few gases analyzed by the SICK MCS100E CEMS have been tabulated. In short, as these results have demonstrated, the analysis results provided by the three extractive CEMS agreed closely with Prism’s reanalysis. The fundamental calibration of the four measurement systems are established in very different ways and have been verified by many independent standards and tests, including evaporative calibration gas generators (e.g., Hovocals) and unchanging reference spectra used for FTIR analysis. The likelihood that the four independent extractive measurement systems all have similar low biases which cause them to agree is vanishingly remote. The cylinder gas analysis results have been evaluated by comparing the % deviation from the tag value relative to the number of days since certification. There are some week correlations suggesting degradation over time. (One participant in the study stated that they continued to see declining HCl concentrations in some of these gases after the period covered by this report.) Similarly, the data have been evaluated to determine if there is a correlation of HCl concentration and deviation from the tag value. However, the data set is to small and of too short duration to draw conclusions. There is insufficient information to discern whether the HCl compressed gas mixtures degrade over time, cannot be quantitatively recovered from the cylinder, or were incorrectly analyzed and labeled by the suppliers. The procedures used by the different vendors for the HCl cylinder gas preparation and analysis are not known. The potential use of HCl compressed gas mixtures for calibration of HCl CEMS where the delivered concentration is significantly less than the certified “tag” value, raises serious concerns for cement kiln monitoring applications. Resulting monitor adjustments would result in incorrect adjustments to the measurement systems, and, are likely to result in RATA and dynamic spike failures immediately following the monitor adjustment, should they be tested. The adjustment would have ultimately resulted in transitioning a compliant monitor that meets proper QA/QC requirements to one that does not. In effect, this increases the stringency of the emission standard and may make it impossible for facilities to demonstrate compliance. This is unacceptable. Second, the observed variations in the percent deviations of the certified value and actual HCl concentration of various cylinders, shows that it is not possible to conduct linearity tests or multi-level calibrations.

Bottle No. Supplier Contents (as measured)Certify Date

Prism Analysis Date

Pressure(psi)

HCl(measured)

HCl (certified)

HClVariation

(%)CC88645 Linde 5.08 ppm HCl 7/5/2012 9/21/2012 2000 1.52 5.08 70%CC352112 Airgas 5.395 ppm HCl 6/25/2012 9/21/2012 1890 4.07 5.40 25%CC353246 Airgas 5.890 ppm HCl 6/25/2012 9/21/2012 1990 4.40 5.89 25%CC38270 Linde 6.00 ppm HCl 9/18/2012 9/21/2012 2000 5.01 6.00 17%CC268081 Airgas 9.395 ppm HCl 6/26/2012 9/21/2012 1800 5.28 9.40 44%CC53180 Linde 10.0 ppm HCl 7/5/2012 9/21/2012 1190 5.25 10.00 48%CC130771 Linde 10.0 ppm HCl 7/5/2012 9/21/2012 190 7.90 10.00 21%CC18216 Linde 10.1 ppm HCl 7/5/2012 9/21/2012 190 6.01 10.10 40%SG9149943 Linde 11.0 ppm HCl 9/18/2012 9/21/2012 2000 9.41 11.00 14%CC349616 Airgas 11.49 ppm HCl 6/26/2012 9/21/2012 1110 8.85 11.49 23%CC349230 Airgas 11.57 ppm HCl 6/26/2012 9/21/2012 250 8.75 11.57 24%CC118683 Linde 11.57 ppm HCl 9/18/2012 9/21/2012 2000 7.93 11.57 31%CC352084 Airgas 11.59 ppm HCl 6/26/2012 9/21/2012 850 8.65 11.59 25%CC88663 Linde 25.0 ppm HCl 9/18/2012 9/21/2012 2000 24.13 25.00 3%CC126719 Linde 25.0 ppm HCl5.10 ppm SF6 7/5/2012 9/21/2012 390 23.20 25.00 7%CC18123 Linde 25.1 ppm HCl5.02 ppmSF6 9/18/2012 9/21/2012 2000 23.90 25.10 5%CC110148 Linde 25.1 ppm HCl4.00 ppm SF6353 ppm N2O 8/8/2012 9/21/2012 2000 22.10 25.10 12%CC53186 Linde 25.3 ppm HCl4.93 ppm SF6 8/20/2012 9/17/2012 1800 17.80 25.30 30%CC267989 Airgas 28.55 ppm HCl 6/25/2012 9/19/2012 1550 21.10 28.55 26%CC30944 Praxair 33.1 ppm HCl 6/6/2012 9/17/2012 25.50 33.10 23%

C143750 Linde

100 ppm HCl4.01 ppm SF6352 ppm N2O 8/8/2012 9/21/2012 1900 85.20 100.00 15%

CC85129 Linde 101 ppm HCl 8/8/2012 9/21/2012 1700 81.00 101.00 20%CC133658 Linde 101 ppm HCl 7/5/2012 9/17/2012 1700 77.00 101.00 24%CC351225 Airgas 107.9 ppm HCl 6/22/2012 9/17/2012 480 86.90 107.90 19%CC353075 Airgas 318.5 ppm HCl 6/27/2012 9/17/2012 1660 294.00 318.50 8%

Table 11‐1 HCl Calibration Gas Analysis

Appendix 1– Project Scope

CoHo

ontinuous Emisolcim (US) Inc.

HCl

ssion Monitor T.

l Cont

Trial (Confident

tinuou

tial)

us Em

TriaApri

ission

al Studil 13, 2012

n Mon

dy 2

itor Syystemms

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

Table of Contents

I.  Objective: ......................................................................................................................................... 3 

II.  Site CEMs System and Manufacturing Site Details .................................................................. 4 

III.  Calibration and Quality Assurance Requirements .................................................................... 5 

IV.  Equipment and Services to be provided by Holcim (US) Inc. ................................................. 7 

V.  Equipment and Services to be provided by CEMs Provider .................................................... 8 

VI.  Performance Evaluation .............................................................................................................. 10 

VII.  Schedule ........................................................................................................................................ 11 

VIII.  Response Details ......................................................................................................................... 12 

Attachments

Attachment 1 – Site Stack Details

Attachment 2 – Site Emissions Details

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

I. Objective: 1. Obtain actual on-site data to assist in the development, support and defense of an HCl

Performance Specification appropriate and achievable for the cement industry. a) Determine accuracy of vendor supplied cylinder gases at concentrations

necessary to meet anticipated performance specifications. b) Determine viability of Analyte Spiking methodologies to establish performance

specification requirements. c) Determine realistic detection limits using commercially available equipment

installed at a cement manufacturing facility. d) Perform a conventional RATA, via third party, on multiple analyzers to determine

which instruments are best suited to meet upcoming HCl standard requirements.

2. Determine what technologies and equipment supplier(s) are best suited to meet future multi-component monitoring requirements.

a) Identify viable equipment for anticipated multi-component analyzer change-out at multiple facilities over upcoming 1-3 years

b) Identify a complete measurement system capable of measuring HCl at relevant detection limits

c) Determine what company provides the best overall CEMs solution to current and future facility monitoring needs.

This project is being completed internally within Holcim, and as such, all information and communications related to this study will be kept confidential unless prior authorization is granted. An evaluation report will be prepared and provided, in some form, to those companies that participate in the trial. We anticipate that the effort will generate data and lessons learned that will ultimately be submitted to the EPA to assist in the formulation of an appropriate HCl Performance Specification and on-going quality assurance procedures. If the study does not provide appropriate or conclusive information, it is possible a report will not be generated, or, provided to EPA.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

II. Site CEMs System and Manufacturing Site Details The Holcim St. Genevieve (GV) plant is a contemporary preheater precalciner kiln system which began operation during 2009. The kiln system has two inline raw mills and operating conditions include: (a) both raw mills operating, (b) one raw mill operating, and (c) no raw mills operating. These operating conditions will affect the associated effluent HCl concentrations, the concentrations of other effluent components including NH3, as well as the effluent gas temperatures. HCl effluent concentrations are expected to be in the range of 0-15 ppm, wet basis. Effluent gas temperatures are expected to be approximately 205°F (two mills on), 255°F (one mill on) and 320°F (no mills operating).

The field trial is expected to include the concurrent evaluation of two extractive FTIR CEMS each monitoring HCl and multiple effluent components and the currently installed Sick Maihak MCS100 hot wet multiple parameter infrared measurement system. The MCS100 has been installed, certified and is maintained to monitor emissions in accordance with permit requirements for SO2, NOx, CO, CO2, and CH4. The MCS100 also provides measurements of non-regulatory parameters (HCl and NH3) for Holcim’s internal purposes. A THC (FID) analyzer and O2 analyzer are included in the measurement system. The CEMS required by permit are generally subject to requirements equivalent to 40CFR60, Appendix B and Appendix F, Procedure 1. Emission measurements provided by multi-component FTIR systems will be compared to the installed MCS100 for SO2, NO, CO, and CO2 to assess accuracy during the evaluation project. Significant differences will be investigated.

The field trail may also include evaluation of other measurement technologies for HCl.

The sampling location is in the main stack on the 8th level of the preheater tower. The sampling location and CEMS shelter are accessed by a service elevator for transport of personnel and equipment. The elevator dimensions are 82" H x 70" W x 147" D (2.1 m x 1.8 m x 3.75 meters) and the lift capacity is 8000 lbs.

The sampling location is approximately eight (8) duct diameters downstream of the nearest flow disturbance and 8 duct diameters upstream of the stack exit and is expected to provide representative (i.e, non-stratified) sampling location for HCl.

1. Plant Photo with Stack Dimensions included as Attachment 1.

2. Facility Address Holcim (US) Inc. 2942 US Highway 61 Bloomsdale, MO 63627

3. Anticipated Emission Levels included as Attachment 2

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

III. Calibration and Quality Assurance Requirements It is Holcim’s intent to evaluate the HCl CEMS in accordance with the EPA draft performance specification and ongoing quality assurance procedures (both currently under development) and/or alternative calibration and quality assurance procedures which may be more appropriate. The procedures and criteria are subject to change. The following requirements are expected to apply:

1. Typical effluent HCl concentrations are expected to be in the range of 0-10 ppm depending on operating conditions. (Historical data will be reviewed to determine maximum expected HCl concentration and presence of peaks/transients and the same review will be performed for NH3).) It is desirable that the upper limit of the measurement range can be adjusted in the field (i.e, 0-10, 0-15, or 0-20 ppm HCl may prove to be optimal). Equipment suppliers should identify limitations or conditions on field adjustment of measurement range.

2. LOD –The limitation of detection must be demonstrated in the field for the complete measurement system after sampling of the effluent for a reasonable period (at least one day) to condition all measurement system components. See discussion at Federal Register Vol. 76, No. 96 May 18, 2011 “Method 301 Field Validation of Pollutant Measurement Methods From Various Waste Media” preamble section “G. Limit of Detection”pages 28666-28667. The calculated noise-limited detection limit for the analyzer should be reported for comparison. The LOD shall be determined in accordance with ASTM D 6348-12 Annex A2 and include the flowing: a. Determination of the noise limited detection limit for analysis of nitrogen or air

introduced at the sample probe (MDC#1). b. Determination of 3 times the standard deviation (3σ) of eight consecutive

measurement cycle results for humidified nitrogen or air samples containing moisture approximating the effluent concentration introduced at the sample probe (MDC#2).

c. Direct determination of the minimum detectable concentration and LOD by analysis of successive analyte spikes of decreasing HCl concentration.

3. HCl CEMS must perform a daily zero and upscale calibration check using an automated procedure involving the introduction of external gas standards at the sample probe, upstream of the outlet particulate filter. Calibration checks may be performed using compressed gas mixtures, gas mixtures produced by evaporative generator (i.e., Hovocal or equivalent) or other humidified gas mixture for which the target concentration can be determined accurately. Equipment suppliers must provide a written explanation of the daily check procedure explaining the calibration standards used, means of initiating the procedure, time required to complete, need for human observation, and application of automatic adjustments, etc. Alternatives to the above may be proposed for consideration, such as introduction of a zero gas and another “calibration transfer standard” together with frequent HCl analyte spikes.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

a. Note 1: It may be possible through the acquisition of daily calibration checks to demonstrate that less frequent calibration checks are warranted after an initial period.

b. Note 2: It is expected that EPA will require daily calibration checks as this is a requirement of the general provisions (See 40CFR63.8(c)(6)) and it requires a formal rulemaking action to change the requirement.

c. Note 3: FTIR CEMS that measure other criteria pollutants and other components are required by regulation to perform daily zero and upscale calibration checks for each parameter (See 40CFR60.13(d)(1),Appendix B, Performance Specifications 2, 3, 4 etc. and Appendix F, Procedure 1).

4. HCl CEMS must be capable of analyzing external gas standards introduced at the sample probe upstream of the outlet particulate filter for the purpose of demonstrating linearity over the measurement range and conducting audits. It is expected that both dry compressed gas mixtures and humidified gas standards will be used during the field evaluation and CEMS responses to each standard will be evaluated. Equipment suppliers must identify the proper flow rate (or means to determine) for the introduction of external audit gases, and any particular limitations or considerations that apply.

5. HCl CEMS must be capable of performing analyte spikes (a.k.a “dynamic spikes”) to assess measurement accuracy at the level of the emission standard and at higher HCl concentration levels with the kiln system operating under raw mill off conditions. The procedure for performing analyte spikes must assure that the spike gas is 10% or less of the spiked samples reaching the sample cell. The procedure must provide for (a) measurement of the total sample flow rate and spike gas flow rate, or (b) determination of the relative dilution ratio by use of tracer compound or other technique. The equipment supplier must provide a detailed explanation of the analyte spiking methodology including the duration of gas injections, criteria for rejecting spike attempts due to temporal variations, and provide associated documentation in the proposal. a. It is desirable that the analyte spike procedure is fully automated and can be

initiated by the system controller. b. It is desirable that the analyte spike procedure can be initiated, performed and

results be obtained via remote access through internet connectivity. 6. In the event that unexplained performance problems are encountered, Holcim

representatives may request access to spectral analysis software or other information necessary to evaluate residuals or other FTIR analysis parameters to investigate the problem and evaluate possible resolution options.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

IV. Equipment and Services to be provided by Holcim (US) Inc.

1. Payment for costs associated with Emission Monitoring, Inc. 2. Payment for costs associated with third party performing one RATA and other

certifications. The Holcim facility will not provide or cover costs associated with additional testing if an instrument does not pass its RATA requirements, or, if the CEMs Provider determines the need for additional testing. Provisions will be made to support additional CEMs Provider funded testing requests when possible at the facility’s discretion.

3. Electrical hook-ups a. GV to provide specifications during on-site meeting

4. Compressed Air hook-up a. GV to provide specifications during on-site meeting

5. Shelter for analyzers a. CEMs Provider to indicate necessary cabinet space and accessibility with

proposal submittal 6. Electrical technician to assist with installation 7. Instrument technicians for daily walk-through (estimate – 15 min per analyzer per

weekday) a. 4-hour classroom and 4-hr equipment training required to be completed by

CEMs Provider prior to turning over equipment to facility 8. Labor associated with analyzer transfer upon reaching facility shipping dock,

installation (including sample port and sample line installation), and general setup assistance

9. Compressed Cylinder Gas to be provided unless Holcim determines that CEMs Provider anticipates using an inordinate volume of gas during the trial

a. CEMs Provider to indicate in proposal the volume and concentrations necessary for the proposed equipment.

b. If CEMS provider elects to use evaporative calibration gas generator (e.g. Hovocal or equivalent) as alternative to compressed calibration gases, supplier shall indicate whether they will supply the device as part of their system or rely on external calibrator.

10. Stack sample ports will be installed prior to delivery and installation of CEMS.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

V. Equipment and Services to be provided by CEMs Provider

1. Turn-key analyzer and sampling system capable of operating independently upon completion of normal installation to stack, compressed gas cylinders, power, and compressed air.

a. System to include a dedicated sampling probe and all associated equipment, including gas sample conditioning, as applicable, and heated sample line

b. System capable of and setup to monitor NOx, SO2, CO, CO2, HCl, and NH3 c. System capable of outputting a 4-20 mA signal for concentration and

relevant operating flags for incorporation into the plant data historian d. Analyzer, cabinet, and infrastructure necessary to facilitate automatic

calibrations e. Sampling probe and line to be used for sample collection f. System capable of collecting, downloading and maintaining a minimum of

one-minute data for a period of 90-days in a format capable of simple incorporation to a MS Excel spreadsheet.

2. Dial-up capability to be provided via mobile phone network by CEMs Provider at their discretion

a. Site will not provide communication access due to the complexity associated with access through the company firewall.

3. Bi-Weekly, (or as recommended by CEMs Provider), site visit to monitor and review CEMS performance. Physical on-site visits may be supplemented by remote access via internet connectivity or phone line provided adequate functionality is supported.

a. A minimum of two reports to be provided to Holcim per month indicating the performance status of the respective analyzer, including the following items; i. All maintenance and system changes completed during prior

maintenance period ii. Current operating status iii. Daily drift levels iv. Necessary maintenance v. Action Log vi. General Communications

4. During installation, or soon after, the equipment supplier shall attempt to perform a short stratification traverse by temporarily moving the sample probe between three sample points (if possible) within the same sample port to detect apparent spatial variation in the HCl concentration. The ratio of the CEMS response to the MCS 100 response may be used to account for temporal variations.

5. After CEMS installation is completed and reliable operation has been established, the equipment supplier shall perform the LOD determinations (See III. 2 above) and will initiate a 7-day calibration drift test applying the daily zero and upscale or alternative routine check procedures.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

6. After reliable CEMS operation has been achieved, equipment supplier personnel shall perform linearity checks and analyte spike tests at least monthly during site visits.

7. Maintain qualified technical on-site for a minimum of three days during the week of the performance test, anticipated to be completed the week of August 13, 2012. Efforts will be made to minimize the time that will be needed from each CEMs Provider.

8. Information to be supplied with proposal (supplier to mark any information that is confidential or proprietary before transmission to Holcim):

a. Information sufficient to describe the sampling and analysis procedures so that knowledgeable persons can assess the adequacy and effectiveness of specific proposed quality assurance procedures, likelihood of interferences or cross-sensitivities, and other relevant factors

b. CEMS operation and maintenance manual c. Written daily calibration check procedures d. Procedures for use of external audit gases e. Analyte spike procedures

9. Contract requirements as it relates to the temporary use of the proposed equipment.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

VI. Performance Evaluation During the entire field project, each measurement system will be evaluated relative to its internal zero and upscale calibration checks and by comparison of HCl measurement data between systems and by inter-comparison of other measurement parameters. A 7-day calibration drift test will be performed after reliable operation has been established.

Equipment supplier technical personnel will perform the initial LOD determination and will perform linearity tests and analyte spike procedures at least monthly while on-site.

Emission Monitoring Inc. together with Prism Analytical Technologies, Inc. and Holcim personnel plan to perform performance tests during the week of August 13. Prism will perform independent sampling and analysis using an extractive instrumental FTIR measurement system operated in accordance with EPA Method 321 to determine HCl concentrations. A stratification traverse will be performed at the measurement location, to the extent possible. Relative accuracy tests will be performed under both mill on and mill off conditions. Each relative accuracy test will include 9 to 12 consecutive sample runs and analyte spikes of the Prism measurement system will be performed before and after test runs. For each installed CEMS, linearity tests and analyte spike tests will also be performed. Other QA evaluations such as repetition of the LOD determination, or calibration comparisons with dry and wet calibration standards may be performed.

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

VII. Schedule April 13, 2012

1. Work Plan provided to prospective CEMs vendors

April 16 – 20, 2012

2. Conference calls to review work plan and answer questions, vendor specific

April 25, 2012

3. Section VIII. Response Details to be received from CEMs vendors

May 1, 2012

4. On-site CEMs Meeting and site tour at GV facility

July 16, 2012

5. Expected start-up of CEMs systems (earlier is ok depending on GV considerations)

August 13 - 17, 2012

6. Performance Test Evaluation

September 7, 2012

7. Draft Report Completed

September 14, 2012

8. Final Report Completed

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

VIII. Response Details Please provide the following details by no later than April 25, 2012.

1. CEMs System a. System Manuals

i. Operations and Maintenance Requirements ii. Power requirements iii. Compressed air requirements iv. Cylinder gas volume requirements – calibration v. Written daily calibration procedures vi. External audit gas procedures vii. Analyte spike procedures (expected date of delivery if not available)

b. System Schematic c. System cabinet dimensions d. Sampling probe flange pattern and requirements

2. Dial-up and communication capability 3. Example bi-weekly report 4. Confirmation that the following dates and resource requirements will be met

a. July 15, 2012 system start-up b. Limited Stratification traverse performed at start-up c. LOD and 7-day calibrations performed upon start-up d. Linearity checks and analyte spike tests to be completed, at a minimum, monthly e. Provide qualified technician for 3-days during August performance evaluation

5. Contract requirements as it relates to the use of the proposed equipment

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

Attachment 1

Holcim Ste. Genevieve - Bloomsdale, MO Page: 4-2EMR Test Report Revision: 0Test Dates: September 14 - 20, 2011 Report Date: November 12, 2011

Figure 4.1 Schematic of the Main Kiln/Raw Mill Stack sampling location.Attachment 1:

Continuous Emission Monitor Trial (Confidential) Holcim (US) Inc.

Attachment 2

Attachment 2 – Anticipated Flow and Concentration Values

A. Stack Gas Expected Concentrations

Constituent Expected Max/Min Range

SO2 10 ppm 0 to 160 ppm

NOX 220 ppm 0 to 550 ppm

CO 140 ppm 0 to 800 ppm

H2S ND ppm to ppm

NH3 4 ppm 0 to >20 ppm

HCl 2 ppm 0 to 30 ppm

Hydrocarbons 18 ppm 0 to 50 ppm

O2 8 % 0 to 40 %

CO2 24 % 0 to 26 %

Opacity <5 % 0 to 20 % B. Stack Gas Conditions at Sample Probe Location

Condition Expected Max/Min Range

Stack Gas Temperature 250 Deg. F 175 to 420 Deg. F

Stack Gas Static Pressure in.w.c in.w.c

Stack Gas Velocity 39000 KSCFH

32000 46500 KSCFH

Water Vapor 7 % MBV 0 15 %

Dust/Particulate Loading 1.3 gr/dscf 5 gr/dscf

Water Drops Yes No

Fuels Burned Oil Nat. Gas X Coal X Other: Petcoke, liquid non-hazardous fuel

C. AMBIENT ENVIRONMENT AT CEMS ENCLOSURE LOCATION

Elevation above sea level: 8th level of tower @ 780

Feet

AmbientTemperature: 40 Min. Deg. F 115 Max. Deg. F

CEMS Shelter Temperature Unusual Atmosphere:

65-80 F controlled None

Relative Humidity: Min. % Max. %

Facility Electrical Power Available: 120 VAC 1 Phase

60 Hz

UPS Electrical Power Available: 120 VAC Phase

Instrument Air Available: 100-110 psi