vided gene sherman - dallas · this guide has been written for hospitals, dental offices,...

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cover file to be provided

by Gene Sherman

i


This document may be reproduced in its entirety without permission fordistribution at no charge to diagnostic and industrial X-ray film processors.

TThhee SSiillvveerr CCoouunncciillThe Silver Council is a national group focused on the environmentally sound management ofsilver derived from the processing of photographic images. The Silver Council is supported bythe photographic chemical and equipment manufacturers and associations and represents morethan 360,000 users. The purpose of the group is to encourage communications between theregulatory and regulated communities, to support scientific research, and to share currentscientific, technical and economic information about silver so that the common goals ofpollution prevention, recycling, water conservation, and compliance can be met.

The Silver Council5454 Wisconsin AvenueSuite 1510Chevy Chase, Maryland 20815Telephone: (301) 664-5150Fax: (301) 664-5156

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FFiillmm PPrroocceessssoorrssThis Guide has been written for hospitals, dental offices, chiropractic clinics, veterinary clinicsand industrial X-ray film processing (i.e., nondestructive testing) facilities. It contains a set ofrecommended operating procedures designed to reduce the amount of silver in film processingsolutions AND the overall volume of solution discharged to the drain.

If your municipality has adopted the Code of Management Practice for Silver Dischargers, usethis Guide to help you implement the requirements of the Code.

If your municipality has not adopted the Code of Management Practice for Silver Dischargers,use this Guide to help you establish an effective silver recovery or silver management program.

LLiimmiittaattiioonnssThe Code of Management Practice Guide for Diagnostic and Industrial X-Ray Film Processorsdoes not supercede existing local regulations. Where the Code has not been adopted, relyingexclusively on this Guide may cause diagnostic and industrial X-ray film processors to be out ofcompliance with local regulations. Therefore, before using this Guide, each diagnostic andindustrial X-ray film processor should check with the local government agency to determine itsregulatory requirements. For more information contact The Silver Council.

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Many individuals representing the health care and industrial X-ray film processing industry havecontributed to the Code of Management Practice Guide for Diagnostic and Industrial X-RayFilm Processors. This guide is the direct result of their participation in the committee process.We gratefully acknowledge all of these contributions.

The participants volunteered their time and expertise, thus ensuring this guide provides anapproach written for diagnostic and industrial X-ray film processors. Our thanks to each of thesepeople and their companies. Special thanks go to The Silver Council for funding this project.

CPAC, Inc.

Delta Medical Systems, Inc.

Envision Compliance Ltd.

Optima Health

Safety-Kleen Corp

The Silver Council

Agfa Division, Bayer Corporation

Eastman Kodak Company

Fuji Medical Systems U.S.A., Inc.

Ilford Photo

Imation Corporation

Konica Corporation

National Association of Photographic Manufacturers

Photo Marketing Association International

White Mountain Imaging

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1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Regulating Silver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

a. Concentration-based Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . 2b. Performance-based Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

What’s the Concern With Silver? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2 Implementing the Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.0 Determining the Category . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Chart - Size Category Based on Type and Quantity of Film Processed Daily . . . . 5

3.0 Small Processors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.1 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.2 Equipment Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1. One or Two Metallic Replacement Cartridges . . . . . . . . . . . . . . 72. Off-Site Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

4.0 Medium Processors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.1 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94.2 Equipment Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

1. Terminal Electrolytic Unit Followed by a MetallicReplacement Cartridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

2. In-line Electrolytic Unit with a Metallic Replacement Cartridge . . 113. Two or More Metallic Replacement Cartridges . . . . . . . . . . . . . 124. Off-Site Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

5.0 Large Processors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.1 Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145.2 Equipment Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1. Terminal Electrolytic Unit Followed by Two or More MetallicReplacement Cartridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2. In-line Electrolytic Unit with Two Metallic Replacement Cartridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

3. Off-Site Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table of Contents

iv


6.0 Pollution Prevention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186.1 Create a Team . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

a. Management Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19b. Staff Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20Pollution Prevention Team Checklist . . . . . . . . . . . . . . . . . . . . . . . . . 21

6.2 Review Your Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22a. Management Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Process Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Inventory Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Spill Response Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22Good Housekeeping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Safety and Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Management Practices Checklist . . . . . . . . . . . . . . . . . . . . . . . 25

b. Equipment Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Crossovers/Squeegees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27In-line Silver Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Standby Water Saver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27Equipment Modifications Checklist . . . . . . . . . . . . . . . . . . . . . 28

c. Process Modifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Solution Regeneration and Reuse . . . . . . . . . . . . . . . . . . . . . . . 29Water Recirculation and Recycling . . . . . . . . . . . . . . . . . . . . . 29Dry Chemicals and Automated Mixing . . . . . . . . . . . . . . . . . . . 29Process Modifications Checklist . . . . . . . . . . . . . . . . . . . . . . . . 30

d. Solid Waste . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Solid Waste Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

6.3 Develop a P2 Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Screening Your Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Worksheet for Screening Options . . . . . . . . . . . . . . . . . . . . . . . 33Point System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Writing the P2 Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34Pollution Prevention Plan Worksheet . . . . . . . . . . . . . . . . . . . . 34

6.4 Put the Plan in Place . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 356.5 Track Your Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Worksheet for Evaluating P2 . . . . . . . . . . . . . . . . . . . . . . . . . . 35Spread the Word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Table of Contents

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AppendicesAppendix A Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Appendix B Electrolytic Silver Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . 40Appendix C Metallic Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Appendix D Off-Site Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46Appendix E Ion Exchange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49Appendix F Testing for Silver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Appendix G Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

Sample Spill Contingency Plan . . . . . . . . . . . . . . . . . . . . . . . . 54Worksheet for Screening Options . . . . . . . . . . . . . . . . . . . . . . . 55Pollution Prevention Plan Worksheet . . . . . . . . . . . . . . . . . . . . 56Worksheet for Evaluating P2 . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Appendix H Assumptions for Size Category . . . . . . . . . . . . . . . . . . . . . . . . . 58

Table of Contents

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Liquid effluent is a by-product ofprocessing diagnostic and industrial X-rayfilms. After silver recovery, this effluent isgenerally discharged to the drain where itgoes to the publicly owned treatmentworks (POTW) for treatment, and eventualrelease back to the environment.

Silver is the component of film that makesit possible to form an image. Duringprocessing the silver is removed from thefilm and goes into the fixer. While a smallamount of silver may be carried over intothe wash water, fixer is the only silver-richsolution produced in a diagnostic andindustrial X-ray processing facility. Silvershould be recovered from silver-richsolutions before they are discharged to thedrain because:

• silver is a non-renewable resource,

• some cities/towns restrict the amountof silver that can be discharged, and

• silver has economic value.

Effective silver recovery requires equipmentthat is appropriate to the size and activitiesof the diagnostic or industrial X-ray filmprocessor. It also requires implementing a

sound preventive maintenance program.Providing you with this silver recoveryinformation is the primary focus of the Codeof Management Practice Guide forDiagnostic and Industrial X-Ray FilmProcessors.

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The other element of the guide is voluntarypollution prevention. In addition torecovering silver efficiently, diagnostic andindustrial X-ray film processors should beconcerned with minimizing the amount ofwaste they create. Waste solutions areliterally money down the drain. In caseswhere the solutions can’t be discharged tothe drain, such as when the processordischarges to a septic system, it costs moneyfor off-site disposal. That’s why it makessense to minimize waste in the first place.The second half of the guide details severalactivities a diagnostic or industrial X-rayfilm processor can voluntarily undertake toreduce waste and save money.

The Code of Management Practice Guidefor Diagnostic and Industrial X-Ray FilmProcessors is an industry-recommendedguide. It is NOT a legal requirement. Itwas written by people just like yourselves

1.0 Introduction

A silver-rich solution is a solution thatcontains sufficient silver that

cost-effective recovery can be done eitheron-site or off-site. For purposes of this

guide, fixer is the only silver-rich solutionproduced from processing films.*

* The Code of Management Practice addresses silver from film processing solutions only.

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— people who manage diagnostic orindustrial X-ray film processing operations.The guide takes the guesswork out ofdetermining the specific silver recoveryequipment configurations and preventivemaintenance activities you need. Termsused throughout this guide are defined inthe Glossary of Terms (Appendix A).

Regulatory agencies can control thedischarge of silver to the drain in twoways:

1. by using concentration-based limitsand regulating the concentration ortotal amount of silver allowed inwastewater, or

2. by using performance-based limits andrequiring that suitable treatment beapplied before the wastewater isdischarged.

aa.. CCoonncceennttrraattiioonn--bbaasseedd lliimmiittssThe traditional means of restricting silver isthrough concentration-based numericallimits in the city sewer ordinance. Forexample, silver may be restricted to fourparts per million (4 ppm).* This means thatfor every million parts of effluent† therecan be no more than four parts of silver.

Concentration-based limits have beenshown to be a poor way to regulatediagnostic and industrial X-ray filmprocessors for several reasons:

1. Our industry conserves water throughstandby water savers and lowerreplenishment chemicals. As we useless water, the concentration of silver inthe effluent increases. Concentration-based limits, therefore, actuallypenalize those who practice waterconservation.

2. Municipal and state sewage treatmentauthorities ideally develop pretreatmentlimitations by comparing wastewatercoming into the sewage treatment plantand the treated water leaving the plant.The discharge of treated wastewatermust meet limits set by the state toavoid impacting the water quality of thereceiving body of water. Localdevelopment of pretreatment limitationshas resulted in widely varied and oftenunrealistic restrictions across thecountry.

3. The sampling point used to determinewhether or not a limit is being met isdetermined by the local sewerauthority. It may be the property linemanhole or a point where all processwastewater is combined. Thisintroduces additional variation fromcity to city.

4. Industry’s ability torecover silver cost-effectively is dependentupon the equipment available in themarketplace. Restrictions in somejurisdictions are so stringent they cannot be met with the best availabletechnology that is economicallyachievable.

bb.. PPeerrffoorrmmaannccee--bbaasseedd lliimmiittssPerformance-based limits are spelled outas a percentage of the silver that must be

* ppm is the same measurement as milligrams per liter (mg/L).

† Effluent means the liquid waste generated from theprocessing of film.

1.1 Regulating Silver

Silver

3


recovered from discharged solutions.These limits provide environmentalprotection while taking into considerationthe amount of silver-rich solutionsgenerated by diagnostic and industrial X-ray film processors, the efficiency of thebest available technology (equipment), andthe capabilities of the generating facility.

The Code of Management Practice placesdiagnostic and industrial X-ray filmprocessors into one of four categories andprovides specific silver recoveryequipment recommendations for eachcategory. The category may vary for eachfilm processing machine in your facility.For example, in a large hospital, there maybe a small machine that runs only fivefilms per day. This machine would fall intothe small category. In the same hospital,there may be a very busy machine thatruns 150 films per day and would,therefore, fall into the medium category.

If the POTW were categorizing yourfacility, it might take into consideration allthe process effluent produced per day inthe entire facility. For our purposes that’snot very helpful. It could easily result inrequiring an extensive silver recoverysystem on every film processing machine— even one on which only a few filmsper day are processed. If you have thistype of situation in your facility, you mayneed to negotiate with your POTW whenit comes to categorizing your equipment.

The exception is in facilities where silverrecovery operations are centralized. Inthese cases, where the fixer from manyprocessors is collected and desilvered in acentral location, the category is based onthe total volume of fixer and processingeffluent produced at the centralizedtreatment site.

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We wear silver jewelry, eat off silverwareand carry silver fillings in our teeth. Thenwhy is the silver in film processing solutionsregulated? The answer has to do with thedifferent forms silver can take. The metallicsilver that we use in eating utensils andjewelry is nontoxic. But some forms of silvercan be very toxic to aquatic organisms. Infact, years ago, silver cation (Ag+) was usedas a biocide in wastewater treatment. Eventoday, silver nitrate is sometimes added tothe eyes of new infants in order to killbacteria.

Because the silver ion is highly reactive, itquickly and easily complexes with materialsin the environment such as sulfides andchlorides, to yield compounds with little orno toxicity. This means that silver rarelyoccurs in ionic or noncomplexed forms. Thesilver found in used film processing fixer, forexample, is in the form of silver thiosulfate,a nontoxic form.

While there is general agreement amongregulators that it’s the ionic form of silverthat’s most toxic, there’s no accurate andrepeatable analytical test method to measurethe ionic species. Therefore, regulations arebased on total silver, with no differentiationmade between ionic and complexed formsof silver.

Silver discharge regulations impact all filmprocessors from the small dental office to thelarge diagnostic imaging clinic to theindustrial X-ray film processor. Whileindividual dischargers may have little impacton the POTW, collectively, diagnostic andindustrial X-ray film processors discharge asignificant amount of silver.

4


The four categories of film processorsidentified in the Code of Practice, are asfollows:

• A small diagnostic or industrial X-ray film processor is one thatproduces less than two gallons perday of silver-rich solutions and no morethan 1,000 gallons per day of total processeffluent. Small processors should recoversilver to at least 90 percent efficiency.

• A medium diagnostic orindustrial X-ray film processor is onethat produces less than 20 gallonsper day of silver-rich solutions and no morethan 10,000 gallons per day of total processeffluent. Medium processors should recoversilver to at least 95 percent efficiency.

• A large diagnostic or industrialX-ray film processor is one thatproduces more than 20 gallons perday of silver-rich solutions and no morethan 25,000 gallons per day of total processeffluent. Large processors should recoversilver to at least 99 percent efficiency.

• A significant industrial user (SIU) is aprocessor that discharges more than25,000 gallons per day of total processeffluent.* SIUs have no set percentagerecovery efficiency as each SIU isindividually permitted.

Through the use of this guide, diagnosticand industrial X-ray film processors,together with the local agency cancooperatively manage silver discharges tosewer. This guide offers a uniform set of

recommendations for controllingphotoprocessing waste and moves awayfrom existing restrictions that are difficult toachieve given today’s technology and ourefforts to conserve water.

Performance-based limits are realistic,given the technology currently available todiagnostic and industrial X-ray filmprocessors. Performance-based limits thatare uniform across the country will allowfilm processors to self-regulate.

Performance-based limits are the best wayto ensure industrial waste is properlymanaged while providing economicincentives to diagnostic and industrial X-ray film processors.

Who is responsible for ensuring this silvermanagement program is implemented? In amedium or large operation, the responsibleperson is most likely the film processingmanager. While the technical servicesdepartment, a quality assurance (QA)technician or even a radiology technologist(RT) may be assigned the job of puttingcertain aspects of the Code in place, thefinal responsibility rests with management.That responsibility cannot be delegated.Even if an outside contractor services theprocessors and silver recovery systems, theresponsibility stays with the diagnostic orindustrial X-ray film processing manager.

In a small facility such as a dental orveterinary office, the doctor is most likelythe responsible person. While a hygienistor assistant may undertake some of theduties of silver management and pollutionprevention, the final responsibility lies withthe person in charge.

1.2 Implementing the Code

* The EPA defines a significant industrial user as a facility thatdischarges an average of 25,000 gallons per day or more ofprocess wastewater to the publicly owned treatment works(POTW) (excluding sanitary, noncontact cooling and boilerblowdown wastewater). Individual municipalities are free to usea more stringent definition. (40 CFR 403.3 (t)(ii))

95%

90%

99%

5


The first step is to determine which of thefour categories best describes each of yourfilm processors: small, medium, large orsignificant industrial user (SIU). Remember:If you have centralized silver recovery, youshould consider the number of filmsprocessed throughout the entire facilityrather than by individual machine.

To determine your size you can monitor thevolume of both fixer and total processeffluent produced daily for each filmprocessor. Then use the definitions on page4 to find out which category best describesyour situation: small, medium or large.

Since it may be easier for you to simplytrack the amount of film used, we’veprovided the chart below that translates thevolume of chemicals used into the numberof films processed. To use this simple chart,follow these steps:

1. Find the box in the left-hand columnof the chart that best describes the typeof film you process — dental, generalpurpose, mammography or industrialX-ray.

2. For a specific film processor, estimatethe number of films processed per day.

3. Move across the row to the squarecontaining the number of films processedper day as estimated above.

4. Look at the heading in that column toidentify the size category for thatprocessing machine.

5. Now, categorize each of the remainingfilm processors if you have more thanone.

For example, a machine processing 60dental radiographs per day would be inthe small category. On the other hand, amachine processing 60 industrial X-rayfilms per day would be consideredmedium. Note: If a machine falls at abreak point between categories (e.g., 100general purpose films), talk with yoursupplier to make sure that you select thecorrect category.

Now that you’ve identified the category ofeach of your processors, let’s move on.

• For small processors, turn to Section3.0 on page 6.

• For medium processors, turn to Section4.0 on page 9.

• For large processors, turn to Section5.0 on page 14.

• SIUs are beyond the scope of thisguide. If you fall into this category, youshould consult your POTW.

2.0 Determining the Category

Dental 1 - 750 751 - 7,500 N/A

General Purpose 1 - 100 101 - 900 901 - 24,000

Mammography 1 - 250 251 - 2,500 2,501 - 24,000

Industrial X-ray 1 - 50 51 - 400 401 - 6,000

Small Medium LargeType of Film Processed

Size Category Based on Type and Quantity of FilmProcessed Daily*

* These numbers are based on the assumptions shown inAppendix H.

6


Remember: The category size of small isbased on an individual machine not thewhole facility. This is done to ensure thesilver recovery equipment and testingrecommendations are appropriate for thesize and utilization of the processingequipment.

Small diagnostic and industrial X-ray filmprocessors have three practical options forachieving a 90 percent removal. These canbe configured in several ways, discussedbelow.

The following options are recommendedfor recovering at least 90 percent of thesilver from silver-rich solutions:

1. one or two metallic replacementcartridges (MRCs)* with manufacturer-specified flow control,† or

2. off-site management, or

3. alternative technology providing atleast 90 percent silver recovery.**

In this section for small diagnostic andindustrial X-ray film processors, we’llreview typical silver recovery equipmentconfigurations for each of the complianceoptions. Detailed information is availablein the appendices.

We’ll also describe the testing methodsand procedures to use with the equipmentto verify that it is recovering at least 90percent of the silver.

Finally, we’ll show you samples of simplesilver recovery logs to use for recordingthe results of the testing.

3.0 Small Processors

3.1 Options

A small diagnostic or industrial X-rayfilm processor is one that produces less

than 2 gallons per day of silver-richsolutions and no more than 1,000

gallons per day of total process effluent.Small processors should recover silver to

at least 90 percent efficiency.

* Facilities that generate less than 0.5 gallons per day of silver-rich solutions need only one MRC. Due to the low volume, asecond MRC would oxidize and channel by the time the firstMRC was exhausted resulting in no additional silver recovery.

† Flow control may be gravity feed or a metering pump,depending upon the design capabilities of the cartridge andthe processing workload. Work with your supplier todetermine the flow control appropriate for your system.

** This option allows for improvements to existing technologyand for new technology, developed after this guide waswritten. It also allows for less commonly used technology thatis available and can meet the percent recovery requirements.

For detailed information about a specificsilver recovery option, how it works, andpreventive maintenance recommendations,refer to:

Appendix C Metallic Replacement CartridgesAppendix D Off-Site Management

3.2 Equipment Configurations

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HHooww iitt wwoorrkkss

In this configuration, the silver-richoverflow from the processor (A) is directedto a holding tank (B). Next, it is fed viagravity or a metering pump (C) at a fixedrate through the metallic replacementcartridges (MRCs) set up in series (E and G).In this diagram two MRCs are shown. Oncethe solution exits the last cartridge in series(H) at least 90 percent of the silver has beenrecovered and the solution can bedischarged to the drain (I) with permission.

TTeessttiinngg mmeetthhooddss

There are two types of testing methodsyou should use:

• once each week, use silver-estimatingtest papers or another method of approxi-mating silver concentration to checkwhether the system is working (if thepaper shows any change in color, thesystem is not working*), and

• once every year, use highly accurateanalytical laboratory testing such asatomic absorption (AA) or inductivelycoupled plasma spectroscopy (ICP). Usean outside service for analytical testing.

TTeessttiinngg pprroocceedduurreess

1. To indicate whether the system isworking, check the solution weekly at

two locations using a method ofapproximating the silverconcentration:• after the first MRC at (F)• after the last MRC at (H)

2. To verify the percent efficiency of thesystem, use an analytical laboratory totest the solution once every year, fromtwo locations:• before the first MRC at (B) or (D)• after the last MRC at (H)

See Appendix F for more informationabout testing for silver.

TTeessttiinngg rreeccoorrddss

• Record all test results in a silverrecovery log. See the examples below.Check with the publicly ownedtreatment works (POTW) to find outhow long to keep records on file.

11.. OOnnee oorr ttwwoo mmeettaalllliicc rreeppllaacceemmeenntt ccaarrttrriiddggeess ((MMRRCCss)) wwiitthh mmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll

Date

7/1/96

7/8/96

7/15/96

P

P

F

P

Silver Recovery LogWeekly Effluent Check*

MRC #1 MRC #2

P

P

* Pass (P) = no color, Fail (F) = color

Date

7/1/96

7/1/97

7/1/98

2,500

Influent Effluent%

Recovery

150 94%*

Annual Test

Silver Recovery Log (ppm)

When the weekly check indicatescartridge failure, refer to theequipment manual for themanufacturer’s recommendations.

* To obtain the percent recovery,use the following formula:100 - (effluent x 100 ÷ influent).

Optional — for low volumes theoverflow may feed directly fromthe film processor to the MRC viagravity.

* This may vary for systems in which the MRCs are rotatedrather than both replaced at the same time.

metallicreplacement

cartridgemetallic

replacement cartridge

8



In this configuration, the silver-richsolution overflow from the processor isstored in a container (A) until it is picked-up by a licensed hauler for off-site silverrecovery, treatment and/or disposal (B).

TTeessttiinngg rreeqquuiirreemmeennttss

There are no Code of ManagementPractice testing requirements for verifyingsilver recovery efficiencies. State wasteagencies, however, may require testing inorder to characterize the waste.

AAddddiittiioonnaall rreeqquuiirreemmeennttss

Diagnostic and industrial X-ray filmprocessors using off-site management mustmeet the following requirements:

• Store the silver-rich solutions incontainers that are compatible withfilm processing solutions.

• If it’s required in your jurisdiction,provide secondary containment forstorage tanks.

• Comply with all applicable hazardouswaste and DOT regulations.

• Keep records of volumes and types ofsolutions transferred off-site. See theexample log below.

• Maintain logs, hazardous wastemanifests and other records for at leastthree years. Make the records availablefor inspection by the sewage treatmentauthorities.

• Verify the contractor is properlylicensed to transport your waste and ishandling it correctly.

22 .. OOffff--ssiittee mmaannaaggeemmeenntt

OO ffff -- SS ii tt ee CChheemmiiccaa ll LLooggDate Amount Type of Manifest

(gallons) Solution NumberDate

9/9/96

10/7/96

44

44

silver - rich photo

silver - rich photo

MI 3084201

MI 3084202

MI 3084203

MI 3084204

MI 3084205

silver - rich photo

silver - rich photo

silver - rich photo

55

48

55

11/4/96

12/2/96

1/6/97

9


Remember: The category size of medium isbased on an individual machine not thewhole facility. This is done to ensure thesilver recovery equipment and testingrecommendations are appropriate for thesize and utilization of the processingequipment.

Medium diagnostic and industrial X-rayfilm processors have five practical optionsfor achieving a 95 percent removal. Thesecan be configured in several ways,discussed below.


1. terminal electrolytic unit followed by ametallic replacement cartridge (MRC)with manufacturer-specified flowcontrol*, or

2. in-line electrolytic unit with a metallicreplacement cartridge (MRC) withmanufacturer-specified flow control*, or

3. two or more MRCs with manufacturer-specified flow control, or


5. alternative technology providing atleast 95 percent silver recovery.**

In this section for medium diagnostic andindustrial X-ray film processors, we’llreview typical silver recovery equipmentconfigurations for each of the complianceoptions. Detailed information is availablein the appendices.



4.0 Medium Processors

4.1 Options

For detailed information about a specificsilver recovery option, how it works, andpreventive maintenance recommendations,refer to:

Appendix B Electrolytic Silver Recovery Appendix C Metallic Replacement CartridgesAppendix D Off-Site Management


A medium diagnostic or industrial X-ray film processor is one that

produces less than 20 gallons per day of silver-rich solutions and no morethan 10,000 gallons per day of totalprocess effluent. Medium processors

should recover silver to at least 95 percent efficiency.

* Flow control may be gravity feed or a metering pump,depending upon the design capabilities of the cartridge andthe processing workload. Work with your supplier todetermine the flow control appropriate for your system.

** This option allows for improvements to existing technologyand for new technology, developed after this guide waswritten. It also allows for less commonly used technology thatis available and can meet the percent recovery requirements.

10


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11.... TTeerrmmiinnaall eelleeccttrroollyyttiicc uunniitt ffoolllloowweedd bbyy aa mmeettaalllliicc rreeppllaacceemmeenntt ccaarrttrriiddggee((MMRRCC)) wwiitthh mmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll

working, check the solution weekly attwo locations using a method ofapproximating the silver concentration:• after the electrolytic unit at (D)• after the MRC at (H)

2. To verify the percent efficiency of thesystem, use an analytical laboratory totest the solution once every sixmonths, from two locations:• before the electrolytic unit at (A)• after the MRC at (H)



• Record all test results in a silverrecovery log. See the examples below.Check with the POTW to find out howlong to keep records on file.

Date

7/1/96

7/8/96

7/15/96

P

P

P

P


Electrolytic MRC

P

F


Date

7/4/96

1/4/97

7/4/97

2,500

Influent Effluent%

Recovery

75 97%*2,530 50.6 98%*

Six Month Test


* To obtain the percent recovery,use the following formula:100 - (effluent x 100 ÷ influent).When the weekly check indicates

cartridge failure, refer to theequipment manual for themanufacturer’s recommendations.


In this configuration, the silver-rich overflow from theprocessor (A) is directed tothe electrolytic unit (B).When sufficient silver-rich solution hasaccumulated, the electrolytic unit beginsto desilver the solution. When the batch iscompleted, the partially desilveredsolution is pumped out (C) of theelectrolytic unit into the holding tank (D).From here, it is metered (E) at a fixed ratethrough the metallic replacementcartridge (G). Once the solution exits thecartridge (H) at least 95 percent of thesilver has been recovered and the solutioncan be discharged to the drain (I), withpermission.



• once each week, use silver-estimatingtest papers or another method of approxi-mating silver concentration to checkwhether the system is working (if thepaper shows any change in color, thesystem is not working), and

• once every six months, use highlyaccurate analytical laboratory testing suchas atomic absorption (AA) or inductivelycoupled plasma spectroscopy (ICP). Usean outside service for analytical testing.


1. To indicate whether the system is

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Where the electrolytic unit is flow-through rather than batch, the holdingtank and pumps are optional.

metallicreplacement

cartridge

11


22 .... IInn-lliinnee eelleeccttrroollyyttiicc uunniitt wwiitthh aa mmeettaalllliicc rreeppllaacceemmeenntt ccaarrttrriiddggee ((MMRRCC)) wwiitthhmmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll


In this configuration, the silver-richoverflow from the processor fixer tank (A) iscontinuously recirculated through the in-line electrolytic silver recovery unit (B) andback into the fixer tank (A). Fixer overflow(C) is fed into the holding tank (D). Fromhere, it is metered (E) at a fixed rate throughthe metallic replacement cartridge (G).Once the solution exits the cartridge (H) atleast 95 percent of the silver has beenrecovered and the solution can bedischarged to the drain (I), with permission.



• once each week, use silver-estimatingtest papers or another method ofapproximating silver concentration tocheck whether the system is working (ifthe paper shows any change in color, thesystem is not working), and



1. To indicate whether the system isworking, check the solution weekly attwo locations using a method ofapproximating the silver concentration:• after the electrolytic unit at (D)• after the MRC at (H)

2. To verify the percent efficiency of thesystem, use an analytical laboratory to

test the solution once every six months,from one location:• after the MRC at (H)

Note: Where an in-line unit is installed, itmaintains the fixer working tank silverconcentration below 1000 ppm. Since it’snot possible to obtain a pre silver recoverysample, we will assume that if the in-lineunit weren’t there, the silver concentration inthe tank would be approximately 2500 ppm.




Date

7/1/96

7/8/96

7/15/96

P

P

P

P


Electrolytic MRC

P

F


Date

7/4/96

1/4/97

7/4/97

2,500

Influent Effluent%

Recovery

75 97%*2,500 50.6 98%*

Six Month Test




metallicreplacement

cartridge

processorworking fixer tank

12


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Optional — for low volumes, theoverflow may feed directly fromthe film processor to the MRC viagravity.

approximating the silverconcentration:• after the first MRC at (F)• after the second MRC at (H)

2. To verify the percent efficiency of thesystem, use an analytical laboratory totest the solution once every sixmonths, from two locations:• before the first MRC at (B)• after the second MRC at (H)



• Record all test results in a silverrecovery log. See the example below.Check with the POTW to find out howlong to keep records on file.

Date

7/1/96

7/8/96

7/15/96

P

P

F

P


MRC #1 MRC #2

P

P


Date

7/4/96

1/4/97

7/4/97

2,500

Influent Effluent%

Recovery

75 97%*2,530 50.6 98%*

Six Month Test




33.. TTwwoo oorr mmoorree mmeettaalllliicc rreeppllaacceemmeenntt ccaarrttrriiddggeess ((MMRRCCss)) wwiitthh mmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll


In this configuration, the silver-rich overflowfrom the processor (A) is directed to theholding tank (B). Next, it is metered (C) at afixed rate through the metallic replacementcartridges (MRCs) set up in series (E and G).Once the solution exits the last cartridge inseries (H) at least 95 percent of the silverhas been recovered and the solution can bedischarged to the drain (I), with permission.



• once each week, use silver-estimatingtest papers or another method of approxi-mating silver concentration to checkwhether the system is working (if thepaper shows any change in color, thesystem is not working*), and



1. To indicate whether the system isworking, check the solution weekly attwo locations using a method of

* This may vary for systems in which the MRCs are rotatedrather than both replaced at the same time.

metallicreplacement

cartridgemetallic

replacementcartridge

13



In this configuration, the silver-richsolution overflow from the processor isstored in a container (A) until it is picked-up by a licensed hauler for off-site silverrecovery, treatment and/or disposal (B).




Diagnostic and industrial X-ray filmprocessors using off-site management mustmeet the following requirements:

• Store the silver-rich solutions incontainers that are compatible withdiagnostic and industrial X-ray filmprocessing solutions.





• Verify that the contactor is properlylicensed to transport your waste and ishandling it correctly.

44.. OOffff-ssiittee mmaannaaggeemmeenntt



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silver - rich photo

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14


Remember: The category size of large isbased on an individual machine not thewhole facility. This is done to make surethe silver recovery equipment and testingrecommendations are appropriate for thesize and utilization of the processingequipment.

Large diagnostic and industrial X-ray filmprocessors have several practical optionsfor achieving a 99 percent removal. Thesecan be configured in several ways,discussed below.


1. terminal electrolytic unit followed bytwo metallic replacement cartridges(MRC) with manufacturer-specifiedflow control, or

2. in-line electrolytic unit with twometallic replacement cartridges (MRC)with manufacturer-specified flowcontrol, or


4. alternative technology providing atleast 99 percent silver recovery.*

In this section for large diagnostic andindustrial X-ray film processors, typicalsilver recovery equipment configurationsfor each of the compliance options.Detailed information is available in theappendices.



A large diagnostic or industrial X-rayfilm processor is one that produces

more than 20 gallons per day of silver-rich solutions and less than 25,000

gallons per day of total process effluent.Large processors should recover silver

to at least 99 percent efficiency.

5.0 Large Processors

5.1 Options For detailed information about a specificsilver recovery option, how it works, andpreventive maintenancerecommendations, refer to:

Appendix B Electrolytic Silver Recovery Appendix C Metallic Replacement CartridgesAppendix D Off-Site ManagementAppendix E Ion Exchange


* This option allows for improvements to existing technologyand for new technology, developed after this guide waswritten. It also allows for less commonly used technology thatis available and can meet the percent recovery requirements.

15



In this configuration, the silver-richoverflow from the processor (A) isdirected to the electrolytic unit (B). Whensufficient silver-rich solution hasaccumulated, the electrolytic unit begins todesilver the solution. When the batch iscompleted, the partially desilvered solution ispumped out of the electrolytic unit (C) intothe holding tank (D). From here, it is metered(E) at a fixed rate through the MRCs (G andI). Once the solution exits the last MRC (J) atleast 99 percent of the silver has beenrecovered and the solution can bedischarged to the drain (K), with permission.



• once each week, use silver-estimatingtest papers or another method ofapproximating silver concentration tocheck whether the system is working (if thepaper shows any change in color, thesystem is not working), and

• once every three months, use highlyaccurate analytical laboratory testing suchas atomic absorption (AA) or inductivelycoupled plasma spectroscopy (ICP). Usean outside service for analytical testing.


1. To indicate whether the system isworking, check the solution weekly at

two locations using a method ofapproximating the silver concentration:• after the electrolytic unit at (D)• after the first MRC at (H)• after the last MRC at (J)

2. To verify the percent efficiency of thesystem, use an analytical laboratory totest the solution once every threemonths, from two locations:• before the electrolytic unit at (A)• after the last MRC at (J)

See Appendix F for more informationabout testing for silver


• Record all test results in a silverrecovery log. See the example below.Check with the POTW to find out howlong to keep records on file.

Date

7/1/96

7/8/96

7/15/96

P

P

P

P


Electrolytic MRC #1 MRC #2

P

F

P

P

P


Date

7/4/96

10/4/96

1/4/97

2,500

Influent Effluent%

Recovery

5 99.8%*

2,420 2.4 99.9%*

2,531 2.5 99.9%*

Three Month Test




11.. TTeerrmmiinnaall eelleeccttrroollyyttiicc uunniitt ffoolllloowweedd bbyy ttwwoo oorr mmoorree mmeettaalllliicc rreeppllaacceemmeennttccaarrttrriiddggeess ((MMRRCC)) wwiitthh mmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll

metallicreplacement

cartridge

metallicreplacement

cartridge

16


22 .... IInn--lliinnee eelleeccttrroollyyttiicc uunniitt wwiitthh ttwwoo mmeettaalllliicc rreeppllaacceemmeenntt ccaarrttrriiddggeess ((MMRRCC))wwiitthh mmaannuuffaaccttuurreerr --ssppeecciiffiieedd ffllooww ccoonnttrrooll


In this configuration, the silver-richoverflow from the processor fixertank (A) is continuouslyrecirculated through the in-lineelectrolytic silver recovery unit(B) and back into the fixer tank(A). Fixer overflow (C) is fed intothe holding tank (D). From here, itis metered (E) at a fixed rate through themetallic replacement cartridges (F and H).Once the solution exits the last cartridge (I)at least 99 percent of the silver has beenrecovered and the solution can bedischarged to the drain (J), with permission.



• once each week, use silver-estimatingtest papers or another method of approxi-mating silver concentration to checkwhether the system is working (if thepaper shows any change in color, thesystem is not working), and

• once every three months, use highlyaccurate analytical laboratory testing suchas atomic absorption (AA) or inductivelycoupled plasma spectroscopy (ICP). Usean outside service for analytical testing.


1. To indicate whether the system isworking, check the solution weekly attwo locations using a method ofapproximating the silver concentration:• after the electrolytic unit at (D)• after the first MRC at (G)• after the second MRC at (I)

2. To verify the percent efficiency of thesystem, use an analytical laboratory totest the solution once every threemonths, from one location:• after the last MRC at (I)

Note: Where an in-line unit is installed, itmaintains the fixer working tank silverconcentration below 1000 ppm. Since it’snot possible to obtain a pre silver recoverysample, we will assume that if the in-lineunit weren’t there, the silver concentration inthe tank would be approximately 2500 ppm.




Date

7/1/96

7/8/96

7/15/96

P

P

P

P


Electrolytic MRC #1 MRC #2

P

F

P

P

P


Date

7/4/96

10/4/96

1/4/97

2,500

Influent Effluent%

Recovery

5 99.8%*

2,500 2.4 99.9%*

2,500 2.5 99.9%*

Three Month Test




metallicreplacement

cartridge

metallicreplacement

cartridge

processorworking fixer tank

17



In this configuration, the silver-richsolution overflow from the processor isstored in a drum (A) until it is picked-upby a licensed hauler for off-site silverrecovery, treatment and/or disposal (B).




Diagnostic and industrial X-ray filmprocessors using off-site managementmust meet the following requirements:

• Store the silver-rich solutions incontainers that are compatible withfilm processing solutions.





• Verify that the contractor is properlylicensed to transport your waste and ishandling it correctly.

33.. OOffff-ssiittee mmaannaaggeemmeenntt



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18


Minimizing or reducing waste is acommon practice among film processors.For example, automated processingchemical mixers are used to reduce wastecaused by mixing errors. Outdatedradiographs and other scrap films are sentto a recycler where the silver is recoveredand the film base is recycled for use inmanufacturing new film. Using good wastecontrol practices has two benefits: it canlower the impact the operation has on theenvironment and it can save moneythrough reduced materials and labor.

In today’s language, waste control iscalled pollution prevention. Pollutionprevention, or P2, is the name given togood management practices, as well asequipment and chemical modificationsthat result in reducing or eliminatingwaste. While P2 activities can be appliedthroughout a facility, in this guide we’llfocus on the film processing area.

Most diagnostic and industrial X-ray filmprocessors are already using somepollution prevention practices. In thissection of the Code of ManagementPractice Guide for Diagnostic andIndustrial X-Ray Film Processors we’re

going to give you a method to look at yourdiagnostic or industrial X-ray filmprocessing operation, identify options forvoluntary pollution prevention, put a P2plan in place and follow-up on the successof that plan. The diagram on the next pageshows the five steps of P2 planning:

1. Create a team of interested andcapable staff and administrativeemployees to develop and overseepollution prevention activities in yourfacility.

2. Review your options by examiningyour current practices in light ofalternative or additional measures that canreduce or eliminate waste.

3. Develop a P2 plan by deciding whichoptions you’ll adopt, the time frame foradopting them, and who will beresponsible for overseeing implementationand maintenance of the option.

4. Put the plan in place by providing thestaff with pollution prevention training andresources.

5. Track your results by keeping recordswhere they are helpful and by routinelyauditing or inspecting your diagnostic orindustrial X-ray film processing operationfor pollution prevention opportunities.

Not every pollution prevention activitydiscussed in this section will make sensefor you. For example, if the filmprocessing volume is low, an in-lineelectrolytic system is probably not a goodchoice. This is just one example of why

6.0 Pollution PreventionThis section of the guide introducesseveral voluntary activities that can resultin preventing pollution. We recommendthat you read through it and adopt anyideas that are appropriate for your filmprocessing operation. While many ofthese activities are better suited to largeroperations, there are some that can alsobenefit even the smallest film processor.

19


it’s so important for you to conduct athorough review of your operation andexamine your options before you begin todevelop a P2 plan.

In the following pages of this section, weprovide you with specific P2 informationand checklists to assess your performance.

Commitment from management and staffis an essential element of a successfulpollution prevention plan.

Management supports the plan by 1) developing, implementing andmaintaining a P2 policy, 2) forming a P2team, and 3) allowing adequate time andresources for P2 activities.

Staff supports the plan by working withmanagement to ensure pollutionprevention is a priority in the diagnostic orindustrial X-ray film processing area.

aa.. MMaannaaggeemmeenntt aaccttiivviittiieessThere’s no substitution for good leadershipin pollution prevention. Management isresponsible for setting the pollutionprevention policy, establishing who will

help with the plan and providing thenecessary resources.

AA ppoolllluuttiioonn pprreevveennttiioonn ppoolliiccyy

A pollution prevention policy is a simpleand clear statement that waste reductionand elimination are goals of your facility.We’ve provided an example of a policybelow. Make sure your policy is signed bya manager to show commitment andresponsibility for P2 activities.

Once the policy is developed, post it forall employees, and perhaps even patientsclients or customers to see. Remember —the success of P2 depends upon supportfrom all the people in the film processingoperation. You may decide to develop thepolicy with the help of the P2 team.

6.1 Create a Team

Pollution prevention is a key

consideration in all our operating

decisions and is the responsibility of

management. We have a P2 plan in

place incorporating internal practices

and procedures that result in reducing

both liquid and solid waste. The plan is

routinely evaluated and modified to

improve our P2 record.

Manager and date

Create a team1 Review your options2

Develop a P2plan3

Put the plan in place4

Track yourresults5

Planning for Pollution Prevention

20


TThhee PP22 tteeaamm

The pollution prevention team is the groupof managers and staff people whodevelop, implement and evaluate all theactivities that go into making up the P2plan.

• How many people should be on theteam? That depends upon the size of youroperation. In a three or four persondiagnostic or industrial X-ray filmprocessing operation, it might be a teamof one — the supervisor. In a large facility,it might be a team of five or six. Youdecide how many people you need.

• Who makes the best team member?The best team member is someone who’sinterested in pollution prevention, whowants to be on the team and who has agood understanding of film processingsystems. In large facilities try to getrepresentatives of different departmentswhere film processing is done.

• What about a team leader? The P2team needs a leader. Management canleave that decision up to the team or itcan designate someone.

TTiimmee aanndd rreessoouurrcceess ffoorr tthhee PP22 tteeaamm

The P2 team needs time and resources todo its job properly. Time means time tomeet, audit the facility, develop the P2plan, put it into action, and periodicallyevaluate it. Resources mean training andtechnical information such as number offilms processed and replenishment rates.Management should provide these as partof its commitment to P2.

bb.. SSttaaffff aaccttiivviittiieessEveryone has a part to play in pollutionprevention. Some staff will be part of theP2 team. Their responsibilities will be tohelp develop the P2 plan and put it inplace.

The rest of the staff will be trained torecognize pollution preventionopportunities and to work in such a waythat doesn’t create waste in the first place.


CChheecckklliissttThis checklist reviews all the elements for putting together a P2 team. When you have the teamin place, you should be able to answer “Yes” to all questions. “No” answers are potentialpollution prevention opportunities. When you don’t have adequate information to answer,check the “?” Then get the information you need to make an assessment.

21

Pollution Prevention Team

Yes No ?

• Do you have a P2 policy?

• Has it been signed and dated by a manager?

• Is the policy posted where all staff can see it?

• Have staff members been told about the P2 policy and its purpose?

• Has the P2 team been formed?

• Are the team members knowledgeable about film processing?

• Has a team leader been chosen?

• Does management provide the team with the time and resources needed for P2 planning and implementation?

22


Pollution prevention options for filmprocessing solutions can be placed into oneof three categories:

1) management practices, 2) equipment modifications, and 3) process modifications.

We’ll examine each of these. We’ll alsolook at options for managing the solidwaste produced in diagnostic andindustrial X-ray film processing.

At this phase of the P2 process, we’re onlylooking at the possible options. After eachdiscussion, we’ve included a checklist foryou to evaluate your practices andequipment. A “Yes” answer means you’realready practicing that P2 activity. Anytimeyou answer “No” you’ve found a potentialpollution prevention opportunity. Anytimeyou answer “?” it means you need moreinformation to evaluate the option. Whenyou finish, look back at the checklists andwith the team, choose the best P2 optionsfor your operation.

aa.. MMaannaaggeemmeenntt pprraaccttiicceessSome of the simplest and least expensivemanagement practices may produce themost effective pollution prevention results.Keep this in mind as we look at thefollowing management practices.

PPrreevveennttiivvee mmaaiinntteennaannccee

Preventive maintenance should be yourfirst pollution prevention option. Byimplementing an effective preventivemaintenance program, the film processingequipment will work at its optimum level,keeping waste at a minimum. Use therecommendations found in the equipment

operating manuals as a starting point foryour preventive maintenance program.Contact the equipment manufacturer formore information.

PPrroocceessss ccoonnttrrooll

Process control is the routine monitoringof variables that affect the quality of yourproduct. These variables include:

• replenishment rates, • processing temperatures• processing times, and• chemical mix procedures.

They should be checked routinely toensure that film image quality is good,image stability is maximized and waste isminimized. These variables should bemonitored on a schedule tied to thepreventive maintenance schedule.

The film processor should also routinelyrun control strips, chart the results of eachstrip (see the control chart on the next page)and take action based on the results.

IInnvveennttoorryy ccoonnttrrooll

Managing the chemical inventory includesrotating the stock so that the oldest is usedfirst and maintaining an appropriate supplyof chemicals on-hand. This reduces theamount of money tied-up in overstock orhaving to dispose of old, unusedchemicals.

SSppiillll rreessppoonnssee ppllaannnniinngg

Any time a solution is unintentionallyreleased it’s a spill. The key word isunintentional. When you produce a wastesolution during processor cleaning andrecharging, it’s intentional. But if acontainer of film processing solution isdropped on the floor, ruptures and leaks,you have an unintentional spill.

6.2 Review Your Options

23


Most spills are minor splashes or leaks andcan be cleaned up with a sponge or mop.Occasionally, however, a larger spill couldoccur requiring specialized clean-upmaterials and procedures.

The time to plan for a spill is long before ithappens. A good spill response plan willhelp minimize the effects of the spill onthe environment and ensure the diagnosticor industrial X-ray film processor returns tonormal as quickly as possible. Some of theitems to include in your spill responseplan include:

• an inventory of all the chemicals usedin the diagnostic or industrial imagingfilm processing operation,

• a floor plan showing the location of allchemicals in the film processing area,floor drains, exits, fire extinguishersand spill response supplies,

• a description of the containment usedfor silver recovery equipment,chemical mixers and storage tanks andany other containers that could leak orrupture,

• a list of spill response supplies andequipment such as mop, pail, sponge,co-polymer or other absorbentmaterials and personal protectiveequipment, and

• a set of tested procedures forresponding to a spill. A sample spillresponse procedure, as shown below,is included in Appendix G.

Film Processor Inc.*

SPILL CONTINGENCY PLANSpill Response Personnel

Name pager/phone

Name pager/phone

Name pager/phone

EnvironmentalEmergencyPhone (999) 999-9999 24 hours a day

7 days a week

EQUIPMENT REQUIRED

• Gloves • Bucket • Absorbent• Apron • Mop Materials• Goggles • Sponge

SPILL RESPONSE PROCEDURES

1. Put on gloves, goggles and an apron.

2. Contain the spill with a mop or absorbent materials available.

3. Check the appropriate material safety data sheet (MSDS) for specialhandling, ventilation, personal protection or other pertinent data.

4. Clean up the spill, as directed, using generous amounts of water.

5. Use the mop and sponge to clean the area thoroughly.

6. Package and label all contaminated absorbent materials for off-sitedisposal.

7. Notify the supervisor or manager that a spill has occurred.

8. (If required) Notify the appropriate government agency that a spillhas occurred.

* This plan will not meet the requirements in all states, including California.

EExxaammppllee pprroocceessss ccoonnttrrooll cchhaarrtt

24


GGoooodd hhoouusseekkeeeeppiinngg

In a clean and orderly facility, there’sbetter control over materials andequipment and less likelihood of spills.This results in less operational waste andprevents pollution.

Good housekeeping is one of thoseinexpensive and simple managementpractices that can significantly reducewaste, increase productivity and lowercosts. You can’t afford to neglect it. Hereare three basic good housekeepingguidelines:

1. Designate an appropriate storage areafor all materials and equipment.

2. Require every employee to return allmaterials and equipment to theirdesignated area.

3. Establish a procedure and a scheduleto inspect chemical receiving, storage,mixing, and use areas for spills, leaks,cleanliness and orderliness.

SSaaffeettyy aanndd sseeccuurriittyy

Keeping chemical areas safe and securecan minimize spills and other upsets.

• Make sure there is always someonetrained in spill response procedures inthe facility or who can be contacted torespond immediately.

• Restrict staff admittance to areas wherechemicals are used and stored to thosewho have had hazard communicationtraining.

• Make sure there’s an MSDS on file forevery chemical in the facility.

• Maintain a security system so that youknow when someone is in the facility,both during and after working hours.


CChheecckklliissttThis checklist reviews all the elements for evaluating management practices. “Yes” answersindicate that you’re already using that pollution prevention measure. “No” answers are potentialpollution prevention opportunities. When you don’t have adequate information to answer,check the “?” Then get the information you need to make an assessment. Mark “N/A” (notapplicable) when the item doesn’t apply in your situation.

25

Management Practices

Yes No ? N/A

• Is there a preventive maintenance program in place incorporating all the equipment manufacturer recommendations?

Yes No ? N/A

• Are solution replenishment rates routinely monitored?

• Are processing tank temperatures routinely checked?

• Are the appropriate staff trained in correct chemical mix procedures?

• Are control strips run on processors at least once per day?

• Are all control strips plotted on control charts?

• When corrective action is taken, is it noted on the control chart?

Yes No ? N/A

• Is the oldest chemical stock always used first?

• Are appropriate levels of stock maintained?

Yes No ? N/A

• Is there a spill response plan?

• Is there an inventory of all chemicals in the film processing area?

• Is there a floor plan detailing the location of chemicals, floordrains, exits, fire extinguishers and spill response supplies?

• Is there containment around all permanent chemical containers?

• Are the spill response supplies easily accessible?

• Are spill response personnel properly trained?

Preventive Maintenance

Process Control

Spill Response Planning

Inventory Control


26

Management Practices (continued)

Yes No ? N/A

• Are all materials and equipment kept in a specified location?

• Are all chemical containers routinely checked for cracks or leaks?

• Is all equipment wiped clean of chemical residue and dirt?

• Are all floors free of chemical spills and residue?

• Are aisles and walkways clear?

• Does the film processing area look orderly and clean?

• Are all employees held accountable for good housekeeping?

Yes No ? N/A

• Is there at least one staff member trained in spill response inthe facility or available at all times?

• Are areas where chemicals are used and stored restricted tostaff trained in safe chemical handling (hazard communication)?

• Where it’s required, is there an MSDS for every chemical?

• Is there a security system in place during both working and nonworking hours?

Good housekeeping

Safety and Security

27


bb.. EEqquuiippmmeenntt mmooddiiffiiccaattiioonnssA second category of pollution preventionoptions is equipment modifications. Thisrefers to the changes made to filmprocessors to reduce the amount of wastesolution produced through processing. Aswe examine each of these optionsremember what we said earlier: Not every one of these options isappropriate for your equipment. In somecases, equipment cannot be modified.Check with your equipment manufacturer.

CCrroossssoovveerrss//ssqquueeeeggeeeess

Crossovers/squeegees are an effective P2option that improves silver recovery. Asthe film exits the fixer tank, it carries overa certain amount of silver-rich solutioninto the wash. Crossovers/squeegeesreduce carryover, therefore keeping thesilver in the fixer tank where the overflowcan be sent to silver recovery instead ofbeing lost in the wash tanks.* Care androutine maintenance can extend the lifeand effectiveness of crossovers/squeegees.

IInn-lliinnee ssiillvveerr rreeccoovveerryy

Another way to reduce the silver carriedover from the fixer tank into the washtanks is to reduce the concentration ofsilver in the fixer. This can be done within-line silver recovery (sometimes calledrecirculating or closed-loop silverrecovery).

In-line silver recovery is an electrolyticunit through which the fixer in theprocessor tank is recirculated andconstantly desilvered. By keeping thesilver concentration in the fixer tank at alower level, the amount of silver lost to

the wash is significantly reduced.There are other benefits of in-line silverrecovery. Generally, it’s possible to use alower fixer replenishment rate whichmeans lower chemical consumption.Additionally, the silver recovered is highgrade silver flake.

If you use in-line silver recovery, checkwith your chemical supplier to determineif you need a specially formulated fixer.

SSttaannddbbyy wwaatteerr ssaavveerr

Today, most processors come equippedwith an extremely efficient water savingdevice called standby water saver. Thiscontrols the wash water so it runs onlywhen film is being processed. When thefilm clears the machine, the wash goesinto standby position and doesn’t beginagain until the next film is processed. Thisequipment modification can savehundreds of gallons of water. If you havean older machine, check with yoursupplier to find out if it’s possible to haveit modified for a standby water saver.

* Crossovers/squeegees are also used between the developerand fixer tanks. This minimizes developer carryover that cancontaminate the fixer.


CChheecckklliissttThis checklist reviews all the elements for evaluating equipment modifications. “Yes” answersindicate that you’re already using that pollution prevention measure. “No” answers are potentialpollution prevention opportunities. When you don’t have adequate information to answer,check the “?” Then get the information you need to make an assessment. Mark “N/A” (notapplicable) when the item doesn’t apply in your situation.

28

Equipment modifications

Yes No ? N/A

• Are there crossovers/squeegees on processors capable of being equipped?

• Are all crossovers/squeegees routinely checked, cleaned and replaced as necessary?

• Are all crossovers/squeegees cleaned as part of the shut-down procedure?

Yes No ? N/A

• Is there an in-line electrolytic unit on all film fixer tanks?

• Is the silver concentration in the tank monitored so that itdoesn’t get below 500 ppm or above 1000 ppm?

• Is the fixer appropriate for in-line silver recovery?

• Has the fixer replenishment rate been reduced?

Yes No ? N/A

• Are the processors equipped with standby wash?

In-line Silver Recovery (if applicable)

Crossovers/Squeegees

Standby Wash (if applicable)

29


cc.. PPrroocceessss mmooddiiffiiccaattiioonnssThe third category of pollution preventionoptions is process modifications. Just aswith equipment modifications, not allprocessors can be changed toaccommodate every one of these processmodifications.

SSoolluuttiioonn rreeggeenneerraattiioonn aanndd rreeuussee

Regenerating and reusing processingsolutions may reduce the amount ofchemicals to be desilvered or dischargedto the drain. If the equipment can bemodified and the film use is high enough,these pollution prevention options cansignificantly reduce waste. Talk with yourfilm and chemical suppliers to find out ifthis option is appropriate for your facility.

Off-site chemical recycling may also be anoption. In this case, the film processingfacility collects the fixer overflow at theprocessor and periodically ships thecollected solution to the recycler. Fromhere, the fixer is desilvered and alsoregenerated for reuse. The regeneratedfixer is then returned to the filmprocessing facility to be used as freshchemical for processing radiographs.

WWaatteerr rreecciirrccuullaattiioonn aanndd rreeccyycclliinngg

Water is a valuable resource and shouldbe conserved. Under certain conditions,wash water recirculators can be used toreduce the volume of water required forprocessing and reduce heat requirementsfor maintaining wash water temperatures.Another alternative is the standby washdiscussed on page 27.

Because wash water has a direct affect onimage stability, always consult with yourmanufacturer before making waterconservation modifications to theprocessors.

DDrryy cchheemmiiccaallss aanndd aauuttoommaatteedd mmiixxiinngg

Under some conditions, dry chemicalpackaging and automated mixing cancontribute to waste minimization throughextended shelf life and less packagingmaterial.


CChheecckklliissttThis checklist reviews all the elements for evaluating process modifications. “Yes” answersindicate that you’re already using that pollution prevention measure. “No” answers are potentialpollution prevention opportunities. When you don’t have adequate information to answer,check the “?” Then get the information you need to make an assessment. Mark “N/A” (notapplicable) when the item doesn’t apply in your situation.

30

Process modifications

Yes No ? N/A

• Have replenishment rates been measured or adjustedto manufacturer specifications?

• Are there opportunities to lower fixer replenishment rates?

Yes No ? N/A

• Is fixer regenerated where it’s practical?

• Is the portion of the silver-rich fixer that is not regenerated sent for silver recovery?

• Are chemicals reused where it’s practical?(e.g., developer or fixer recirculators)

Yes No ? N/A

• Are wash water rates set at manufacturer recommendations?

• Does the wash water run only during processing?

• Is wash water conservation being used? (e.g., wash water recirculator or standby wash)

Yes No ? N/A

• Are dry chemicals used where it’s practical?

• Are automated mixers used where it’s practical?

Solution Reuse

Replenishment

Water Reuse and Recycling

Other Process Modifications

31


dd.. SSoolliidd wwaasstteeThere are pollution preventionopportunities for reducing the solid wasteproduced in diagnostic and industrial X-ray film processing. For example, film canbe sent out for polyester plastic processingand silver refining. Local recyclers willaccept cardboard from film boxes, theouter cardboard from chemical containersand they may also accept thoroughlyrinsed plastic liners.

Many cities have recycling programs formost of the solid waste generated in yourfilm processing area. Reusing andrecycling reduces the amount of solidwaste going to landfill and lowers yourwaste disposal fees.


CChheecckklliissttThis checklist reviews all the elements for evaluating your solid waste management program.“Yes” answers indicate that you’re already using that pollution prevention measure. “No”answers are potential pollution prevention opportunities. When you don’t have adequateinformation to answer, check the “?” Then get the information you need to make an assessment.Mark “N/A” (not applicable) when the item doesn’t apply in your situation.

32

Solid Waste

Yes No ? N/A

• Plastic film bags?

• Cardboard film boxes?

• Packing materials including pallets and plastic wrap?

Yes No ? N/A

• Film?

• Unwanted or excess exposed and processed film?

• Lead sheets?

• Plastic chemical bottles and box liners?

• Plastic chemical box liners?

• Corrugated cardboard?

• Office paper?

• Box board?

• Packing materials including pallets and plastic wrap?

list additional items here

Are the following solid wastes reused:

Are the following solid wastes recycled:

33


Now that the P2 team has finished theaudit or review, it’s time for them to lookat all the options and prioritize them as:

• High priority — needs immediateaction

• Medium priority — needs actionwithin 3 to 12 months

• Low priority — needs considerationwithin the next 1 to 2 years

SSccrreeeenniinngg yyoouurr ooppttiioonnss

Screen each option by asking thefollowing questions and writing out youranswers:

1. What is the potential for reducingwaste and providing otherenvironmental benefits?

2. What is it going to cost in time andmaterials?

3. How much money will it save in timeand materials?

4. How difficult is it to implement?

5. Does it have an adverse affect onimage quality?

Review the example below for screeningthe option of using in-line silver recoveryon the film processor. A blank worksheetis included in Appendix G. Make copiesas you need them and leave the originalin this guide.

6.3 Develop a P2 Plan

Worksheet for Screening Options Date

Option: (example) Installing and maintaining an in-line silver recovery unit on the processor

1. What is the potential for reducing waste and providing other environmental benefits?Less silver will be lost to the wash tank and therefore the drain. In addition, we may be able toreduce replenishment rates.

2. What is it going to cost in time and materials?Cost of the electrolytic unit, labor for installation and periodic replacement, and labor formaintenance. (Note: estimate actual costs as closely as possible.)

3. How much money will it save in time and materials?The savings will come in the increased amount of silver recovered (Note: estimate actualsavings as closely as possible) and lower fixer replenishment rates.

4. How difficult is it to implement? Not difficult. We can schedule the installment during the next preventive maintenance check onthe machine. We need to buy the electrolytic unit. We also need to train process operators tokeep the silver concentration about 500 ppm to reduce the potential for sulfiding.

5. Could it have an adverse affect on image quality? No, providing it’s properly set-up and maintained.

10/2/96

34


Screening all the options you’ve identifiedwill take time but it’s time well spent. It’svery important that you actually write outyour answers. Doing your homework heremakes the difference between a P2 planthat exists only in your head vs. one that isimplemented and working.

PPooiinntt ssyysstteemm

You might find it useful to develop a pointsystem for rating all the options. Forexample, you could assign a plus value toevery potential benefit and a minus valueto every negative impact.

WWrriittiinngg tthhee PP22 ppllaann

Whatever system you use, you need toprioritize all of the options. Now you canbegin to draft the P2 plan. For your firstattempt at systematic pollution prevention,we recommend that you start with onlythe high priority options. Work at gettingthese into place and evaluate your success

before addressing the medium and lowpriority options. Don’t make too manychanges as once — start with only three orfour items.

Keep your P2 plan simple. Here is theinformation you should include:

• Spell out each option and its purpose

• State a specific date when the optionwill be implemented

• List who is responsible

• Note if a record will be kept

Review the example below. A blankPollution Prevention Plan Worksheet isincluded in Appendix G. Make copies asyou need them and leave the originals inthis guide.

Pollution Prevention Plan Worksheet Date

Option or activity: (example) Install the in-line unit on the film processor in order

to reduce the amount of silver in the wash water.

Implementation date: The unit will be installed during the December preventive

maintenance check.

Responsibility: Joe Smith, maintenance supervisor, will arrange to buy the unit,

ensure it is installed and be responsible for seeing it is maintained. He will also train

the process operators how to maintain the unit and harvest the silver.

Record: In-line electrolytic maintenance will be added to the preventive maintenance

checklist.

11/10/96

35


Now that you have a P2 plan it’s time toput it into action. These are the steps:

1. Make the plan known - Post it, explainits purpose and details to the staff, and talkit up. Through both your words andactions, make all employees aware of howcommitted the management is to pollutionprevention. Keep employees updated onboth the successes and failures of theplan.

2. Provide training and education - Makesure that anyone who is given responsibilityin the P2 plan has the training andknowledge to carry out his/her tasks.

3. Provide the necessary resources - Makesure that anyone who is given responsibilityin the P2 plan has the time and materialsrequired to fully implement the P2 plan.

Your P2 plan isn’t a “Now I’ve done it so Ican forget about it” kind of thing. Youneed to periodically review it, evaluate

which elements are working, which needto be modified and which need to bediscontinued. A review every six monthsshould be often enough.

As you evaluate your P2 plan, keep inmind your original intent for pollutionprevention: minimizing or eliminatingwaste for both environmental andeconomic benefit.

Answer each of the following questions foreach pollution prevention option oractivity listed in your plan:

• How much waste has been reduced oreliminated as a result of this activity?

• How much has it cost?

• How much money has it saved?

In some cases, it may be hard to get exactanswers to these questions. But try. It’simportant that you fully evaluate every P2option implemented in your diagnostic orindustrial X-ray film processing operation.Once again, let’s look at installing an in-line unit as an example.

6.4 Put the Plan in Place

6.5 Track Your Results

Worksheet for Evaluating P2 Date

Option: (example) Installing and maintaining an in-line electrolytic silver recovery unit on the film processor

1. Waste reduction resultsUsing colorimetric testing, we found the concentration of silver in the wash tank went from 95ppm to 28 ppm. Over the 6 month period, we estimate this is 386 troy ounces of silver.

2. CostsMaterials: unit = $1,240. Labor: installation 1-1/2 hours x $20/hour = $30. Daily maintenance:1 minute at $12/hour = $.20 daily or $24 for 6 months. Total costs = $1,294.

3. Savings386 troy oz. of silver at $5.40 tr. oz. = $2,084. This was the amount of silver diverted fromthe wash. Total savings realized were $2,084 - $1,294 = $790.00 in six months.

5/17/96

36


A successful P2 option or activity is onethat reduces waste and saves more moneythan it costs. Consider whether changing itwould make it even more successful orwhether to let it continue as is.

An unsuccessful option or activity is onethat doesn’t reduce waste, or it costs moremoney than it saves. With an unsuccessfuloption, consider whether changing itwould make it successful or whether todiscontinue using it.

Once you’ve done this evaluation forevery option, you can also considerwhether it’s time to put some of thosemedium priority options in place.Remember not to make too many changesat once.

SSpprreeaadd tthhee wwoorrdd

Every time you evaluate the success of theP2 plan, let the staff know the results —both the positive and the not so positive.When you decide to make changes orimplement new P2 activities, remember totrain the staff if there are any newprocedures.

Include your P2 success stories in yourfacility’s annual report or newsletter. Ifthere’s no environmental section in thereport, now is a good time to start one.

With pollution prevention, everyone’s awinner: the impact of your business on theenvironment is reduced and the costsavings from lower waste means moremoney in your pocket.

P2P2

37

AMSA: The Association of MetropolitanSewerage Agencies represents the interestsof the country’s largest wastewatertreatment agencies. AMSA maintains a keyrole in the development of environmentallegislation and implementation ofenvironmental rules, guidance and policy.

Anode: The positively charged electrode.When electrolytically desilvering filmprocessing solutions, the thiosulfate isoxidized at the anode.

Batch Process: The collection of silver-richsolution into a tank or container which isprocessed through a silver recovery ormanagement system.

Biocide: A chemical that discourages thegrowth of bacteria.

Cathode: The negatively chargedelectrode. When electrolyticallydesilvering film processing solutions,metallic silver is deposited on the cathode.

Code of Management Practice (CMP): Thesite-specific plan implemented by theindividual processing facility for thepurpose of controlling and reducingdischarges of silver to the POTW.

Continuous Process: The processing ofsilver-rich solution in a continuous flowfrom the processing machine through asilver recovery or management system.

Cradle-to-Grave: A phrase used todescribe the tracking system for hazardouswaste. All parties in the waste chain —generator, transporter, storage and disposalfacilities — use a common manifest thatidentifies them, the waste, and the finaldisposition of the waste.

Diagnostic or Industrial X-Ray FilmProcessing Facility: A facility using thephotographic process in creatingdiagnostic or industrial images.

DOT: Department of Transportation

Effluent: The solution exiting a process orpiece of equipment.

Electrolytic Silver Recovery: A method ofrecovering silver in which a direct currentis applied across two electrodes immersedin a silver-rich solution. Silver plates ontothe cathode and the thiosulfate is oxidizedat the anode.

Good Housekeeping: Maintenance of aneat, orderly and clean working environment.

Influent: The solution entering a processor piece of equipment.

In-Line Silver Recovery: A method ofrecovering silver in which fixer iscirculated between the processor fixertank and an electrolytic unit. An in-lineunit continuously recovers silver and

Appendix AGlossary of Terms



38maintains it in the fixer at a reduced level,typically between 500 ppm - 1,000 ppm.This method of silver recovery is alsocalled closed-loop or recirculating silverrecovery.

Ion Exchange: A reversible exchange ofions between a solid (resin) and a liquid(water containing ionized salts). Whenused with film processing solutions, ionexchange removes the silver ion fromsolution and replaces it with non silver ion.

Large Diagnostic or Industrial X-ray FilmProcessor: A processor which produceson average more than 20 gallons per day(GPD) of silver-rich solution and usesmore than 10,000 GPD of process washwater.

Low-Silver Solution: A solution containinginsufficient silver for cost effective silverrecovery. Low-silver solutions includeused developers, stop baths and washwaters.

Medium Diagnostic or Industrial X-RayFilm Processor: A processor whichproduces on average less than 20 gallonsper day (GPD) of silver-rich solution anduses less than 10,000 GPD of processwash water.

Metallic Replacement: A method ofrecovering silver from silver-rich solutionsby an oxidation-reduction reaction withelemental iron and silver thiosulfate toproduce ferrous iron and metallic silver.The device used is commonly called ametallic replacement cartridge (MRC).

Milligrams per Liter (mg/L): mg/L is thesame measurement as parts per million(ppm).

MRC: A metallic replacement cartridge isa device which recovers silver through aprocess known as metallic replacement.

Off-Site Silver Recovery andManagement: Removal of silver-richsolutions from a facility by a haulingservice to a recovery facility.

On-Site Silver Recovery and Management:The management and treatment of silver-rich solutions on the premises in which thesilver-rich solutions are generated.

Pollution Prevention: Any practice thatreduces or eliminates waste at the source.

POTW: Publically owned treatment works.A wastewater treatment facility owned bythe public (municipality or serviceauthority).

Preventive Maintenance: A set ofprocedures routinely performed onequipment and processes to reduce therisk of a malfunction.

Pretreat: To change the characteristic of awaste by treatment before it is dischargedto a POTW.

Significant Industrial User (SIU): Anyindustrial user that discharges an averageof 25,000 GPD or more of processwastewater to a POTW, contributes aprocess waste stream which makes up fivepercent or more of the average dry weatherhydraulic or organic capacity of thePOTW, or, is designated as such by theControl Authority on the basis that theindustrial user has a reasonable potentialfor adversely affecting the POTW’soperation or for violating any pretreatmentstandard.


39Silver Recovery: The process of reclaimingsilver from silver-rich solutions such asfixers.

Silver-Rich Solution: A solution containingsufficient silver that cost effective recoverycould be done either on-site or off-site.Fixer is a silver-rich solution.

Silver-Estimating Test Paper: A test papercoated with cadmium sulfide whichchanges color on reacting with silver insolution. A reference color code allowsusers to estimate the amount of silver insolution.

Small Diagnostic or Industrial X-Ray FilmProcessor: A processor which produceson average less than 2 gallons per day(GPD) of silver-rich solution and uses lessthan 1,000 GPD of process wash water.

Source Reduction: A decrease in theproduction of the volume, concentrationor toxicity of liquid waste.

Spill: Unintended release of liquid that isnot in the ordinary course of events.

Squeegee: Physical device (e.g. rollers,blades) used on processors to removeresidual surface liquids before the film orpaper travels from one processor tank tothe next.

Sewer: An underground conduit forcarrying wastewater to a POTW.

The Silver Council: A national groupsupported by the photographic chemicaland equipment manufacturers andassociations and representing more than360,000 users. The purpose of the groupis to encourage communications betweenthe regulatory and regulated communities,to support scientific research, and to sharecurrent scientific, technical and economicinformation about silver so that thecommon goals of pollution prevention,recycling, water conservation, andcompliance can be met.

40

Electrolytic recovery is an efficient andcost-effective silver recovery technologyfirst used in 1931. Since then theequipment has evolved and been refinedso that today’s electrolytic units arereliable and consistent. The equipment iscontinuously reused and few, if any,additional chemicals are required toperform the recovery operation.

Throughout this discussion, refer to thediagram in the right-hand column. Inelectrolytic silver recovery two electrodesare immersed in silver-rich solution.Electric current reduces the silver-thiosulfate complex in the solution andplates almost pure silver metal onto thecathode — the negatively chargedelectrode. The cathode is typically madeof stainless steel. The amount and qualityof the silver plated out depends upon theoperating amperage and the length of timethe solution is exposed to the current.

There are two basic types of electrolyticequipment: one in which the cathode rotates in the solution and the other inwhich the solution flows around astationary cathode. Either type ofequipment is capable of recovering asignificant amount of the silver from thesilver-rich solutions.

In addition, there are batch units andflow-through units. In the batch unit, the

solution is collected within a chamberinside the electrolytic unit until there issufficient quantity to constitute a batch.The solution is then pumped into thedesilvering chamber where the silver isremoved. When the batch is completed, itis pumped out all at once, usually to asecondary silver recovery system. In aflow-through unit, the silver is recoveredcontinuously as it flows into the unit. Thissolution is then displaced as moreprocessor overflow enters the electrolyticunit. Electrolytic units should be used inconjunction with another system.

In-line electrolytic silver recoveryBy using in-line electrolytic silver recoveryon fixer solutions, the amount of silver insolution is significantly reduced. Thisresults in less silver carried over into thefinal wash water and subsequentlydischarged to the sewer. Where the use ofin-line silver recovery is possible, mixingand chemical usage can be reduced by upto 50 percent, further increasing the cost

Appendix BElectrolytic Silver Recovery


B.1 How it Works

Electrolytic Unit


41

effectiveness of this technology. Thisapproach may not be feasible in allcircumstances. Solution overflow from in-line systems should be treated by anothersystem to further reduce the silverconcentration.

The electrolytic unit must have enoughcapacity to treat peak volumes of silver-rich chemical effluent produced by thefilm processor. The manufacturer/supplierof the electrolytic unit can help thediagnostic or industrial X-ray filmprocessor choose the appropriateequipment and provide preventivemaintenance information. Generallyelectrolytic units are monitored for thefollowing: pH, silver concentration, sulfiteconcentration, time and amperage, and,mechanical operation. All of these arediscussed below.

aa.. ppHHFixer solutions from film processes areeasy to desilver electrolytically andrequire little, if any, pH adjustment.*

bb.. SSiillvveerr ccoonncceennttrraattiioonnThe concentration of silver in theoverflows from diagnostic and industrialX-ray film processing operations willtypically range from 2,000 - 3,000 ppmprior to electrolytic recovery but canreach as high as 6,000 ppm.

Recovery efficiency is directly related tosilver concentration; the higher the silver

concentration, the higher the platingefficiency. Replenishment rates play animportant role in determining thisconcentration level. Over replenishmentdilutes the amount of silver. When silverconcentration falls below 500 mg/L,plating efficiency decreases significantlythus reducing the recovery rate of theelectrolytic unit.

It's very important to calibratereplenishment rates routinely on theprocessors.

cc.. SSuullffiittee ccoonncceennttrraattiioonnIn the plating process, sulfite is consumedas silver is plated out of solution. It’snecessary, therefore, to have sufficientsulfite in the solution. This is particularlyimportant in in-line electrolytic silverrecovery where the fixer solution iscontinually recirculated through theprocessing tank. Any degradation of thefixer can affect the final product. Checkwith the equipment manufacturer orchemical supplier to find out if you shouldbe using a fixer with an increased level ofsulfite.

dd.. TTiimmee aanndd aammppeerraaggeeMany of the electrolytic silver recoveryunits sold today are automatic so theoperator doesn't have to set platingcurrent and batch times — two criticalfactors in electrolytic silver recovery. Thecorrect plating current must be maintainedto drive the silver out of solution and ontothe cathode. If the plating current is toohigh or the plating time too long, the silverdeposited on the cathode will be blackand sludgy, with much of it falling off thecathode and collecting on the bottom ofthe electrolytic unit. This situation, knownas sulfiding, results in a low quality silver

* It is highly recommended not to exceed a pH of 8.5.Above this level significant ammonia air emissions arereleased.

B.2 Operation/Maintenance


42

and a mess to clean. To avoid sulfiding,follow the manufacturer recommendationsfor setting both the plating time andamperage.

Attempts to achieve higher efficienciesthan those recommended by themanufacturer can actually lead to lowersilver recovery. By over extending theplating time or significantly raising thecurrent density, sulfiding will occur. Thisresults in coating the cathode with a blacksulfide precipitate rendering it unsuitablefor continued silver recovery.

ee.. MMeecchhaanniiccaall ooppeerraattiioonnGeneral mechanical preventivemaintenance should be conductedperiodically to ensure the plating currentis correct, the cathode is rotating or thepump is working, and the color of thesilver on the cathode is creamy-grey ratherthan black or white. The silver should beharvested (removed from the cathode)periodically and sent to the refiner.

The most common mechanical problemwith electrolytic units is a poor electricalconnection to either the anode or thecathode. It is important that terminals andwires do not come in contact withsolutions. Corroded terminals or cableswill result in poor plating.

The person who is responsible for silverrecovery should follow all manufacturerrecommendations for preventivemaintenance and keep accurate recordsof any maintenance performed.

• Make sure you receive theoperations and maintenancemanuals for your silver recoveryequipment. These manuals are partof the purchase price of yourequipment and you are entitled tothem.

• Obtain data from the silverrecovery equipment manufacturer/supplier demonstrating theperformance capability of theequipment. For example, if you arerequired to recover silver to 99percent efficiency, ask themanufacturer to provide you withdata showing the equipment canachieve this level.

43

Metallic replacement is a relatively lowcost method of achieving a fairly highlevel of silver recovery.

Metallic replacement is a process thatoccurs when a solution containingdissolved ions of an active metal, such assilver, contact a more active solid metal,such as iron. The more active metal, ironwhich is contained in a cartridge, reactswith the silver and dissolves in solution.The silver in solution is reduced to metallicsilver and collects in the cartridge.

In essence, the dissolved silver in solutionchanges places with the solid iron in thecartridge. The exchange reaction isdependent upon the contact of the silver-thiosulfate in solution with the ironsurface. To ensure good and controlledcontact, metallic replacement isaccomplished by metering the silver-richsolutions through a cartridge of iron. Assilver is removed from the solution, theiron metal filler in the cartridge becomesdepleted. The cartridge is then replacedwith a new cartridge and the accumulatedsilver sludge is sent to be refined.

A typical metallic replacement cartridge(MRC) is shown in the diagram above.

There are a variety of MRCs on the markettoday. They contain iron in the form of

chopped steel wool, spiral wound steelwool, a heavy iron mesh similar to doorscreening material, or iron chipsimbedded in a fiberglass support.

A properly designed and maintainedsingle-cartridge MRC system is capable ofrecovering more than 95 percent of thesilver from silver-rich solutions when usedin accordance with manufacturer specifiedflow rates. A system utilizing two MRCshooked in series is capable of recovering99 percent of the silver.

Where the flow of solution through thecartridge exceeds its rated capacity, flowcontrol must be used. While a meteringpump is generally recommended, in

Appendix CMetallic Replacement


Metallic Replacement Cartridge

C.1 How it Works

grating or mesh for solution dispersion


44extremely low volume situations a flowrestrictor may be adequate.

The manufacturer/supplier of the MRC canhelp the diagnostic or industrial X-ray filmprocessor choose the appropriateequipment. The manufacturer is also thebest source of preventive maintenanceinformation. Generally metallicreplacement cartridges are monitored forthe following: flow rate, channeling,obstruction, pH, and, cartridge capacity.

aa.. FFllooww rraatteeThe length of time the silver-rich solutionis in contact with the iron is critical foreffective silver recovery. If the solutionflows through the MRC too quickly, it willnot contact the steel wool long enough forthe iron/silver reaction to occur. The lowerthe flow rate, the better the recovery.

A pump may be used to meter the solutionat a prescribed rate from the holding tankto the first MRC in the series. To ensureproper flow rate, calibrate the meteringpump each time the MRCs are replaced.Consult the manufacturer for the optimumflow rate.

bb.. CChhaannnneelliinnggAs the recovery cartridge is exposed tofixer, the active surface area is used upand small channels will begin to developin the iron material. This is known aschanneling. It also occurs when an MRCis used only intermittently due to lowvolume or when the solution is introducedin batches. When a small volume ofsolution enters the MRC and sits on thesurface, it slowly eats through the steel

wool, forming a vertical shaft or channelas it goes. As more solution enters theMRC, it takes the path of least resistanceand flows through the channel, thuscontacting very little of the steel wool inthe cartridge. This causes only a smallamount of the iron to be used (that alongthe channel). When channeling occurs,only low levels of silver are recovered andhigh levels are discharged from the MRC.

To avoid channeling: (1) select the propersize MRC for the average volume of filmprocessed through the machine, and (2)fill the MRC with water just prior tointroducing chemical solutions into it.

cc.. OObbssttrruuccttiioonnWhen the iron in solution contacts air,iron hydroxide or rust forms. If the rust isallowed to build up in the lines leadinginto and out of the MRCs, it caneventually restrict the flow of solutioncausing the solution to back up. The MRCmay also leak around the fittings andcover.

Obstruction also occurs when the centercore of the MRC is crushed or damagedand the solution cannot pass through it. Ifthis happens, replace the MRC with a newone. Consult the MRC supplier forinformation.

Finally, rust that passes through the MRCcan eventually build up in the floor drain,requiring expensive drain cleaning.

Monitor the system regularly forobstruction. Remove the lines and rinsethem with hot water each time the MRCsare replaced. Do this more often if thereare several hours each day when nosolution is flowing through the MRCs. Be

C.2 Operation/Maintenance


45

sure to run the overflow system downhillso there’s no chance of back-up.

dd.. ppHHFor best results with MRCs, the pH shouldbe between 4.5 to 5.5. If the pH is toolow, the steel wool is etched too quicklyreducing the life of the MRC. If the pH ofthe solution is too high, etching does notoccur so the silver/iron exchange reactioncan't take place. Also, at higher pH levels,iron hydroxide (rust) is formed which cancause obstructions in the lines and drains.

Try to maintain a consistent pH in theinfluent going to the MRCs. This is bestaccomplished by plumbing the silver-richoverflow directly from the processors tothe silver recovery system. Manuallyemptying waste tanks tends to introducepH variation into the system. Normally, asolution containing fixer will not requirepH adjustment. Work with yourequipment supplier to determine the bestpH for your MRCs.

ee.. CCaarrttrriiddggee ccaappaacciittyyEach type of MRC has a limited capacity torecover silver depending on the type andamount of iron used and conditions in thefilm processing lab. Manufacturersgenerally rate the capacity of their MRCs inboth gallons of solution and time. Forexample, depending on the silverconcentration of the influent, an MRCmight have the capacity to desilver 100gallons of solution or last 12 weeks,whichever comes first. Ask themanufacturer to help you in selectingMRCs appropriate for your lab.

KKeeeeppiinngg aa llooggKeep a silver recovery log to record all ofthe checks and testing you do on your

The person who is responsible for silverrecovery should follow all manufacturerrecommendations for preventivemaintenance and keep accurate recordsof any maintenance performed.

• Make sure you receive theoperations and maintenancemanuals for your silver recoveryequipment. These manuals are partof the purchase price of yourequipment and you are entitled tothem.

• Obtain data from the silverrecovery equipment manufacturer/supplier demonstrating theperformance capability of theequipment. For example, if you arerequired to recover silver to 99percent efficiency, ask themanufacturer to provide you withdata showing the equipment canachieve this level.

silver recovery equipment. As soon as theweekly check (done with silver-estimatingtest papers) shows color, you know themetallic replacement cartridge has failedand it’s time to change it. When you installa new MRC, mark the installation date onthe cartridge.

Check with your local POTW authorities tofind out how long to keep these records onfile.


46

aa.. GGeenneerraattoorr ccaatteeggoorryyIf you’re shipping waste diagnostic orindustrial X-ray film processing solutionscontaining 5 ppm or more of silver, it’simportant that you know how todetermine your hazardous waste category.The specific requirements foraccumulation, storage, and manifestingvary depending on the category.

The chart on the next page shows thethree categories of waste generatorsestablished in the federal ResourceConservation and Recovery Act (RCRA).These categories, as shown across the topof the chart, are:

• Conditionally exempt small quantity generator

• Small quantity generator

• Large quantity generator

To determine your category, track themonthly volume of waste film processingsolutions containing 5 ppm or more ofsilver produced in your facility to be sentoff-site. This amount must be added to theamount of any other hazardous wasteproduced by your facility, in determiningthe generator category.

For example, if you process film in severallocations within your facility and thesolutions are accumulated and taken off-site, add all the fixer produced in all

The following information applies only todiagnostic and industrial X-ray filmprocessors that ship waste off-site.

In some situations, off-site silver recoveryis the best option. For example:

• Diagnostic and industrial X-ray filmprocessing operations required to meetexcessively restrictive silver concentrationlimits may be forced to ship the solutionsoff-site for treatment.

• For diagnostic and industrial X-ray filmprocessing facilities discharging to a septictank and leach field, there is no option;they must haul. Diagnostic and industrialX-ray film processing chemicals must notbe discharged to septic systems. Thiscould cause an upset that would destroythe microorganisms responsible forbreaking down the wastewater.

Solutions containing 5 ppm or greater ofsilver are currently classified as hazardouswaste. In order to transport these solutionsoff-site, the facility must fulfill therequirements for transporting hazardouswaste. In this section, we’re going todiscuss the Federal requirements for off-site silver recovery. Since individual statesmay enact stricter regulations, make sureyou check with your state agency for itsspecific requirements.

Appendix DOff-Site Management

F.1 Off-Site Requirements


47

locations for one month. If it’s not morethan 100 kilograms (approximately 220pounds or 25 gallons), and you have noother hazardous waste, your facility fallsinto the category of conditionally exemptsmall quantity generator.

bb.. GGeenneerraattoorr iiddeennttiiffiiccaattiioonn nnuummbbeerrSQGs and LQGs must obtain an EPAidentification number before shippingwaste off-site. This 12-character numberidentifies both your site where the waste isproduced and the type of waste. It’s a keyelement of tracking the waste from cradle-to-grave. Your state hazardous wasteagency can provide you with the properpaperwork.

In some states, CESQGs do not have toobtain an ID number.

cc.. AAccccuummuullaattiioonn aanndd ssttoorraaggeeCESQGs must not accumulate more than270 gallons of waste at any time.

SQGs must not accumulate more than1,620 gallons of hazardous waste in any180 day period.

LQGs must not accumulate hazardouswaste on-site longer than 90 days.In all cases, wastes must be stored in tanksand containers suitable for film processingwaste. In addition:

• Clearly mark each container with thewords Hazardous Waste and with thedate you began to collect waste in thatcontainer.

• Use only containers in good condition.

• Keep containers closed except whenyou fill or empty them.

• Inspect areas where containers arestored, at least weekly, looking forleaks and deterioration.

• Provide secondary containment whereit’s required.

dd.. LLaabbeellss aanndd mmaarrkkssContainers of silver-rich chemicals mustbe properly labeled and marked. The labelshown on the next page contains the sixrequired elements:

Hazardous Waste Category*

Conditionally Exempt Small Small Quantity Large QuantityQuantity Generator (CESQG) Generator (SQG) Generator (LQG)

* Any film processing waste containing 5 ppm or more of silver is considered hazardous under the ResourceConservation and Recovery Act (RCRA). Most states and municipalities have additional regulations for the dischargeand transport of silver and silver-bearing wastes. For more information contact your local state hazardous waste agency.

Facility that generates nomore than 100 kilograms ofhazardous waste per month

Facility that generates greaterthan 100 but less than 1,000kilograms of hazardous wasteper month

Facility that generates greaterthan 1000 kilograms ofhazardous waste per month


48

accumulation start date,

EPA waste identification number(silver is D011),

site name and address where thewaste was produced (generator name),

EPA generator identification number,

manifest number, and

Department of Transportation (DOT)shipping name for the waste. (this isthe correct shipping name for silver-bearing waste.)

ee.. MMaanniiffeessttssThe manifest is a multi-copy documentused to track the waste from the time itleaves the generator (the diagnostic orindustrial X-ray film processing facility), tothe time the receiver treats, recycles ordisposes of it. Each party in the link —generator, transporter, receiver — haveEPA identification numbers and each mustcomplete its portion of the manifest.

The generator is responsible for obtainingnumbered manifest forms from the state

hazardous waste agency. All links in thechain keep a copy of the manifest andreceive copies from the other links toacknowledge receipt of the waste.Manifests must be kept on file by thegenerator for at least three years. Manifests are not required for CESQGs.Some transporters, however, may still askthat they be used to help the transporterand receiver fulfill their requirements.

ff.. SSppiillll rreessppoonnssee aanndd ttrraaiinniinnggSQGs and LQGs are required to developemergency plans and train employees onemergency response so that if a spill oraccident occurs, the facility is ready.Generally, the plans must includeprocedures and identify the necessary spillcontrol/response equipment.

One important element of the cradle-to-grave waste management system isliability. Once you’ve generated the waste,you retain some responsibility even afterturning it over to a licensed transporterand a licensed receiver. This means youshould choose your waste managementpartners carefully.

Talk with your colleagues, tradeassociations and state hazardous wasteagency to get the names of licensedcompanies that could handle silver-bearing film processing wastes. Choose afirm with a good reputation. Verify theirEPA identification numbers and anyrequired permits. Keep copies of theirpermits on file. Visit their site to look attheir equipment and the general conditionof their operation. Choose carefully andwith confidence.

F.2 Precautions

HAZARDOUS WASTEFederal Law Prohibits Improper Disposal

If found, contact the nearest police or public safety authority, or the U.S.Environmental Protection Agency

Accumulation Start Date: EPA Waste #:

Generator Name:

Address:

City: State: Zip Code:

EPA ID #: Manifest #:

DOT Proper Shipping Name, Class, UN#, and packing group:

Dec. 5, 1996 D011

Film Processor Inc.

1500 Main Street

Your Town

XXXXXXXXXXX YYYYYY

NY 02143

RQ Hazardous waste liquid, n.o.s. (silver), Class 9, NA 3082, Packing group III

1 2

3

3

3 3 3

4 5

6

1

2

3

4

5

6

49

Ion exchange technology can be used torecover silver from dilute processingsolutions and wash waters. Keep silverlevels as low as possible in wash water byinstalling and maintaining equipment andmonitoring replenishment rates.

Ion exchange is recommended for useonly to remove silver from wash water. Itis not generally recommended for usewith fixer solutions.

Ion exchange is a reversible exchange ofions between a solid (resin) and a liquid(water containing ionized salts). When ionexchange is used with low-silver solutions,the silver thiosulfate in solution is adsorbedto the resin in the column. Periodically,under a service contract, the column isremoved and the resin is rinsed with adilute sulfuric acid solution to decomposethe silver thiosulfate to silver sulfide, whichremains in the ion exchange column. Theresin is reused for many cycles and is thenincinerated to recover the silveraccumulated in it.

Ion exchange should not be used forrecovering silver directly from silver-richfixer solution.

These concentrated thiosulfate solutionswill strip silver from the resin, and canactually result in more silver being

discharged from the resin column than ispresent in the feed solution. Ion exchange,therefore, lends itself only to the recoveryof silver from wash waters and diluteprocessing solutions. Typically, more than90 percent of the silver from wash waterscan be removed in a single-columnsystem. Two-columns used in series canprovide 99 percent silver removalefficiency.

Converting equipment to incorporate in-line silver recovery greatly reduces thesilver content of the final wash water. Ionexchange technology is most effectivewhen used in conjunction with an in-linesilver recovery unit for the preceding fixersolution.

Appendix EIon Exchange


G.1 How it Worksdesilveredsolution to drain

low silversolution in

outlet

Ion Exchange Column

G.2 Operation/Maintenance


50

Factors affecting the efficiency of ionexchange include: thiosulfateconcentration, flow rate, and biologicalgrowth control.

aa.. TThhiioossuullffaattee ccoonncceennttrraattiioonnThe capacity of the resin to retain silver isvery dependent on the concentration ofthiosulfate in the influent. The higher thethiosulfate, the lower the capacity. That’swhy ion exchange is not recommended forrecovering silver from fixer. These solutionsare high in thiosulfate.

If you operate under such severe dischargerestrictions that you must use ion exchangeto recover silver from silver-rich solutions,two steps are required:

1. desilver the silver-rich solutionsthrough an electrolytic unit, and

2. meter the desilvered solutions into thecollected wash water overflow at a ratenot exceeding their replenishment rate.

These procedures will reduce the silverconcentration prior to ion exchange andensure the thiosulfate levels are controlled.

bb.. FFllooww rraatteeThe low-silver solutions must be meteredthrough the ion exchange columns at aprescribed rate in order to allow for theexchange between the silver and the resinto occur. Generally, this should neverexceed 1 bed volume of resin/minute.

cc.. BBiioollooggiiccaall ggrroowwtthh ccoonnttrroollAlgae, bacteria and fungi grow quitereadily in ion exchange columns and feedon the dilute film processing chemicals.This growth causes two problems: 1) itforms a film on the resin beads, therebyblocking the silver exchange reaction, and2) it obstructs the flow of solution throughthe column.

To eliminate the problem of biologicalgrowth, the ion exchange column(s) mustbe flushed routinely with biocide.

51

You should routinely monitor your silverrecovery system to make sure it’soperating correctly. There are two differenttesting methods recommended:approximations utilizing test papers areperformed frequently, and exact analyticaltesting is performed every three months,six months or annually, depending on thesize of the diagnostic or industrial X-rayfilm processor.

Silver-estimating test papers are used toprovide only an approximation of howmuch silver is in a solution. The test stripsare coated with yellow cadmium sulfidethat forms brownish-black silver sulfidewhen it comes into contact with silver.The higher the concentration of silver insolution, the greater amount of brownish-black silver sulfide will be formed. Thecolor formed on the test strip after it hasbeen in solution, therefore, reflects theamount of silver contained in thatsolution.

Generally, the procedure for using the teststrips is as follows:

1. Dip the test strip in the samplesolution for two (2) seconds so that thestrip is properly wetted.

2. Remove the test strip from solution,shake off any excess liquid, and placethe strip on a white card.

3. After about 15 seconds, compare thecolor of the moist test strip with thecolor key provided with the test strips.Find the color that most closelymatches. That is approximately theconcentration of silver in solution.

4. When evaluating a solution that hascolor, such as seasoned fixer, rinse thetest strip briefly under running watertoward the end of the 15-second waitingperiod. Take the color of the solutioninto consideration when you’re makingthe comparison with the color key.

A typical color key scale is shown below.As you can see from the scale of numbersranging from 0 to 10 g/L* (0 - 10,000mg/L), the silver readings are onlyapproximations of the actual silver insolution. Note that the lowest detectionpoint is 0.5g/L or 500mg/L (500 ppm).

The test strips are helpful in estimating theamount of silver in the solution exiting thesilver recovery system. Once the solutionhas gone through primary silver recovery,the concentration of silver should be below

Appendix FTesting for Silver


H.1 Silver-Estimating Test Papers

SSiillvveerr CCoonntteenntt ooff FFiillmm PPrroocceessssiinngg SSoolluuttiioonn

Grams per Liter

Comparison

Color

Patches

0 10.5 1.75 2.5 3.5 5 7 10

* Silver-estimating papers are generally scaled in grams perliter (g/L) rather than parts per million (ppm). Remember:mg/L and ppm are the same measurement.


52the 500 mg/L (ppm) mark. Since the lowestrange on the silver-estimating test papers is500 ppm, you should see no color changeon the paper. These papers are only usefulfor finding major problems with the silverrecovery system.

For example, if you are using metallicreplacement cartridges, you should testthe cartridge effluent using test strips todetermine the presence of silver. Theeffluent should be below 500 ppm andtherefore, not change the color of the teststrip. The only thing you’ve learned fromtesting the effluent with a test strip is thatthere are no major problems with themetallic replacement cartridges.Periodically, use a more exactingmeasurement to verify the percentage ofsilver the system is recovering.

Only an exact analytical measurementusing EPA protocols can verify whether thesilver recovery system is achieving aspecific percentage recovery. Use anoutside analytical laboratory to analyzethe solution samples.

You may obtain a sample bottle andinstructions from a suitable analyticallaboratory. Generally, fill the bottle with asample of the solution to be analyzed andbring the bottle to the laboratory. Whenthey have finished the procedure, theanalytical laboratory will report the resultsof the analysis to you.

Your best source of informationconcerning your sampling procedures andtechniques is the analytical lab that’sdoing your work. Work with them closelyto get your best results. Following aresome general considerations for sampling:

aa.. SSaammppllee ccoonnttaaiinneerrss• Obtain appropriate containers from theanalytical laboratory. Don’t use glassbecause silver precipitates more easily onthe wall of a glass container.

• Make sure the laboratory knows thatyou are specifically testing for silver sothey provide you with the correct size andtype of container.

bb.. SSaammppllee pprreesseerrvvaattiioonn• Tell the analytical laboratory NOT touse a nitric acid preservative with thesample. Nitric acid precipitates the silverout of solution, thereby providing anartificially low silver reading.

• Return the sample to the analyticallaboratory as quickly as possible to avoidany change in the make-up of the sample.

cc.. SSaammpplliinngg mmeetthhooddoollooggyy• If you are asked to perform thesampling yourself, use the protocolsspecified by the analytical laboratory.

• Make sure that none of the equipmentyou are using to collect the sample hasbeen contaminated with another solutionor material.

dd.. AAnnaallyyttiiccaall tteesstt mmeetthhooddssThere are two EPA-approved methods theanalytical laboratory can use to detectsilver in the sample:

1. Inductively coupled plasmaspectroscopy (ICP)

2. Atomic absorption (AA)

Either test will provide the same result.

H.2 Analytical Testing


53

Appendix GForms


54

Film Processor Inc.*

SPILL CONTINGENCY PLANSpill Response Personnel

Name pager/phone

Name pager/phone

Name pager/phone

EnvironmentalEmergencyPhone (999) 999-9999 24 hours a day

7 days a week

EQUIPMENT REQUIRED

• Gloves • Bucket • Absorbent• Apron • Mop Materials• Goggles • Sponge

SPILL RESPONSE PROCEDURES

1. Put on gloves, goggles and an apron.

2. Contain the spill with a mop or absorbent materials available.

3. Check the appropriate material safety data sheet (MSDS) for specialhandling, ventilation, personal protection or other pertinent data.

4. Clean up the spill, as directed, using generous amounts of water.

5. Use the mop and sponge to clean the area thoroughly.

6. Package and label all contaminated absorbent materials for off-sitedisposal.

7. Notify the supervisor or manager that a spill has occurred.

8. (If required) Notify the appropriate government agency that a spillhas occurred.

* This plan will not meet the requirements in all states, including California.


55

Worksheet for Screening Options Date

Option:

1. What is the potential for reducing waste and providing other environmental benefits?

2. What is it going to cost in time and materials?

3. How much money will it save in time and materials?

4. How difficult is it to implement?


56


Option or activity:

Implementation date:

Responsibility:

Record:


Option or activity:

Implementation date:

Responsibility:

Record:


57


Option:

1. Waste reduction results

2. Costs

3. Savings


Option:

1. Waste reduction results

2. Costs

3. Savings


58

Appendix HAssumptions for Size Category

The Chart on page 5, entitled Size Category Based on Type and Quantity of Film Processed Daily,was created using the assumptions listed below. If your situation doesn’t fit the assumptions usedhere, please consult with your suppliers and service providers to establish your category.

Dental • The average daily run is 20 - 30 intraoral or extraoral films.

• The replenishment rate for both the developer and fixer is 10 ml per film. This is 0.00264 gallonsper film.

• The wash water rate is 1.33 gallons per film.

General Purpose • The average daily run is 50 - 100 sheets of intermixed size general purpose films.

• The fixer replenishment rate is 85 ml per film. This is 0.0224 gallons per film.

• The developer replenishment rate is 65 ml per film. This is 0.0172 gallons per film.

• The wash water rate is 1 gallon per minute.

• The process cycle time is 90 seconds.

Mammography• The average daily run is 60 - 150 sheets of intermixed size mammography films.



• The wash water rate is 1 gallon per minute.

• The process cycle time is 150 seconds.

Industrial X-ray (Nondestructive Testing)• The film size is 14” x 17”



• The wash water rate is 4 gallons per film.

• The process cycle is 12 minutes.

vided gene sherman - dallas · this guide has been written for hospitals, dental offices,...

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