Dissolved NH3 Monitor

Model Q45N Model Q45N

A pplications

• Wastewater Treatment• Potable Water Treatment• River and Stream Water Quality• Refrigeration Chillers

Continuous monitoring of ammonia in water andwastewater streams is becoming increasinglyimportant for plant operations and process control.Unfortunately, on-line ammonia monitors aregenerally very expensive, complex, and laborintensive instruments. Most are automated versionsof ammonia selective ion electrode methods bettersuited to laboratory measurements. Others areautomated colorimetric devices or instrumentalmethods that are difficult to justify on a cost basis.

ATl has developed a completely new approach toon-line monitoring of ammonia that is far lessexpensive and much simpler than conventionalmonitoring equipment. The Q45N DissolvedAmmonia Monitor uses reaction chemistry thatconverts ammonia in solution to a stablemonochloramine compound equivalent inconcentration to the original ammonia level. Thechloramine concentration is then measured with aunique amperometric sensor that responds linearlyto chloramines while eliminating interference fromexcess free chlorine in solution.

Q45N monitors are available in two versions, onethat includes all components convenientlyintegrated into a Nema 4X fiberglas enclosure, and asecond that separates the monitor from thechemistry system for applications where a moreconvenient display location is desired. A sample inletfilter assembly attached to the side of the enclosureallows filtered sample to be drawn from the inletflow. Sample must be pumped to the inlet assemblyat a rate high enough to insure the desired responsetime for the measurement system. Excess sample isbypassed to any convenient drain location.

The electronic display and alarm packageprovides the user interface to the system. Ammoniaconcentration is displayed on a large format LCDdisplay with secondary display for other operatingvariables. Operating ranges for the ammonia monitor

are 0-2 or 0-20 PPM, with a low end resolution ofabout 0.05 PPM. Response time to changes inammonia concentration is less than 60 seconds to90% of a step change in concentration, making thesystem much faster responding than competitivemonitors. Two programmable alarm relays areavailable for local alarm functions, and two analog 4-20 mA output signals are provided for interface toplant DCS, telemetry, or other supervisoryinstrumentation.

ATl's Q45N monitoring package for dissolvedammonia provides the measurement stability neededto avoid complicated automatic calibration systems.Unlike typical ammonia SIE sensors subject tosignificant drift problems, the amperometric sensorprovides excellent repeatability for long periods oftime. And because the measurement utilizeschloramine conversion for measurement, the sampleis inherently subjected to biocidal conditions,eliminating long term biofouling on the sensor.

This new ammonia system represents a majorstep forward in providing users with a monitor thatis both simple to operate and economical topurchase, selling for 50% of the cost of manycompetitive ammonia monitors. Contact your localATI representative for additional assistance in theapplication of this system to your requirements.

ChloramineSensor

Sample

Reagent A Reagent B

Total NH3Sensor

Free AmmoniaOutput (4–20mA)

MonochloramineOutput (4–20mA)

Chloramination Process Monitoring

Chloramination is increasingly being used in potablewater systems to limit THM formation and insuredisinfection in large distribution systems. Propercontrol of this process requires the addition ofsufficient ammonia to insure that onlymonochloramine is formed while limiting theamount of excess ammonia to a minimum.

An enhanced version of the Q45N DissolvedAmmonia Monitor is available that provides anexcellent tool for monitoring the chloraminationprocess. This system employs two separate sensors,the first measuring monochloramine and the secondmeasuring total ammonia after reagent addition.

From these measurements, the monitor willcalculate "Free Ammonia" concentration, whicheffectively is the excess ammonia that has notcombined with chlorine.

This Free Ammonia version can provide twoseparate 4-20 mA outputs and those outputs may beprogrammed to track Free Ammonia, TotalAmmonia, or Monochloramine concentration. Forchloramination systems, it provides operatingpersonnel with continuous confirmation that theprocess is running correctly, or warns of processproblems.

Model Q45N Specifications

Represented By:

PDS-Q45N (08/10)

Measurement: Total ammonia (as NH3 - N)Optional: Free Ammonia (as NH3) and

MonochloramineSensor Type: Amperometric membraned cell Range:

Ammonia: 0-2.000 PPM minimum, 0-20.00PPM Maximum

Monochloramine: 0-10.00 PPMResponse Time: 90% in 120 seconds Accuracy: ± 0.1 PPM or 2% of full scale Sensitivity: 0.05 PPM minimum Zero Stability: ± 0.02 PPM per week Electronic Linearity: ± 0.5% Span Drift: Generally less than 5% per month

(application dependent) Zero Drift: ± 0.03 PPM Analog Output: Two isolated 4-20 mA, 575 ohms max.

Power: 115 or 230 VAC, 50/60 Hz., 5 VAmax.

Alarm Relays: Two SPDT, 5 A @ 230 VAC resistive Relay Coil: Programmable either normally

energized or normally de-ener-gized.

Enclosure: Nema 4X Fiberglas, wall mount Controls: 4 membrane switches on front

of monitor. Operating Temperature: 0° to +40° C Sample Inlet: 1/2" FNPT Sample Drain: 1/2" FNPT Recommended Sample Flow: 0.1-0.5 GPM (0.4 - 2.0 LPM) Size: 15.2" H x 13.W x 7.1" D

(386 x 335 x 180 mm) Weight: 17 lbs. (7.7 Kg.)

Note: The basic ammonia monitor is sup-plied with the spare parts necessary to runthe instrument for approximately 12months, with the exception of reagents.An initial supply of reagents to operate forapproximately 45 days is supplied as partof the base price. Additional reagents maybe purchased in concentrate form.

Suffix A - Measurement 1 - Total Ammonia only 2 - Free Ammonia & Monochloramine

Suffix B - System Style1 - Integrated single enclosure system 2 - Separate monitor and chemistry

module (25 ft. cable) Suffix C - Power

1 -120 VAC, 50/60 Hz.2 - 230 VAC, 50/60 Hz.

Ordering Information:Q45N-A-B-C DissolvedAmmonia Monitor

Typical System:

Reagent BReagent A

AC Power

1/4" – 1/2"Sample Tubing

3/8" – 1/2"Drain Tubing

Analytical Technology, Inc.6 Iron Bridge DriveCollegeville, PA 19426Phone: 610/917-0991• Toll-Free: 800/959-0299Fax: 610/917-0992E-Mail: sales@analyticaltechnology.com

Analytical TechnologyUnit 1 and 2 Gatehead Business ParkDelph New Road, DelphSaddleworth OL3 5DEPhone: +44 (0) 1457 873 318Fax: +44 (0) 1457 874 468E-Mail: sales@atiuk.com

Web Site: www.analyticaltechnology.com