EQUIPMENT AND SERVICE COMPANY, INCORPORATED FX- 300 ISE Ammonia, Nitrate, Nitrite Measurement

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1 FX-300 Online Ammonia, Nitrate, Nitrite Monitor and Controller The Foxcroft FX-300 with ion selective electrode technology can be used as an online monitor and control method for Ammonium (NH4+), Ammonia (NH3), Nitrate (NO3), and Nitrite (NO2) in select locations in the nitrogen reduction process, or to monitor fresh water and fresh water aquaculture. The FX-300 is designed to be a simpler, lower cost alternative to some sample conditioning analyzers where the application allows; producing real time measurements that can provide you a more detailed status of your process and possibly reduce grab sampling frequency. The modular design allows you to select either a single channel transmitter or a monitor for total unbound ammonia, free ammonia, nitrate, nitrite, ph, temperature, ORP, conductivity and DO all in one package. FX-300 Features / Benefits Unique membrane technology results in a combination sensor that does not need rebuilding or maintenance; and provides enhanced selectivity over interfering ions. You can often expect twice the sensor life compared to competitive sensors depending upon water quality. The flexibility to configure the FX-300 as a simple transmitter, or as a controller for any combination of measurements and functions to suit your application and budget. For example, you can configure one unit to display & transmit total ammonia and conductivity readings, monitor nitrate with alarm functions, and monitor ph and ORP with alarm and control functions. Monitor nitrate or nitrite without interference from turbidity or chemical oxygen demand (COD) that can be problematic for optical sensors. Minimize maintenance and ownership costs due to rugged ISE sensors that require no reagents, no sample preparation, no rebuilding. Standard weekly sensor cleaning is usually sufficient for secondary wastewater treatment. 1-point grab sample offset calibration quickly standardizes the instrument with your interference compensated grab or lab analysis used for reporting WITHOUT removing the sensor from service. Unique Membrane Technology Engineered from the ground up and extensively field tested, unique proprietary membrane and reference technology provides significantly improved sensor life and selectivity of ammonia over potassium; and nitrate over chloride ions, versus traditional ion selective electrode (ISE) membranes.

2 Typical Applications Single channel Ammonia Nitrogen (NH3-N), ph, nitrate (NO3-), nitrite (NO2-), conductivity or ORP for secondary or tertiary wastewater treatment monitoring, aqua culture and process control. Potable water monitoring nitrate, ph, conductivity. Wastewater influent monitoring ammonium / ammonia nitrogen, ph, conductivity. Wastewater nitrification & denitrification multi-channel monitoring and control in select sampling points to assure full nitrification and prevent excessive chlorine consumption due to high nitrite levels. Wastewater final effluent monitoring nitrate, ph, conductivity. Drinking water distribution systems low level ammonia & nitrate monitoring. Industrial air scrubbers - ammonia solution concentration measurement. Environmental monitoring of natural water sources: DO, ph, conductivity, nitrate. Available Parameters & Measuring Ranges FX-300-NH4: Ammonium ion concentration in clean potable water through wastewater and industrial processes. Also configurable to measure ph compensated total ammonia (NH3-N). Municipal wastewater range: 1 ppm to 999 ppm Municipal drinking water range: 0.2 ppm to 999 ppm FX-300-NO3: Nitrate ion concentration in clean potable water through wastewater and industrial processes. Range 0.62 ppm to 999 ppm units in nitrate ion, (for NO3-N units divide ion units by 4.43 to determine Nitrate as nitrogen). FX-300-NO2: Nitrite ion concentration in drinking water through select wastewater and industrial processes that contain no unbound sulfides. Range 0.46 ppm to 999 ppm units in nitrite ion, (for NO2-N units divide ion units by 3.29 to determine Nitrite as nitrogen).

3 Compensation For ISE Electrodes Is Not a Valid Solution Measuring ammonium and nitrate ions using traditional older ISE membrane technology has been problematic due to interfering potassium and chloride ions that are present in concentrations typically found in processes outside of the laboratory. Often the solution has been to measure the interfering ion with a second electrode and compensate for the effect of the error on the primary measurement. However, there is no widely accepted scientific consensus that an ion selective sensor can be compensated for interferences with a second ISE sensor in continuous field applications. Interference is a degenerative process, exposure to levels outside the range of the sensor gradually degrades the sensor to the point it becomes unresponsive. Online process streams can have varying analyte and interfering ion levels, temperature, and sample background. Such continuous change in the sensor characteristics and sample, combined with potential uncertainty of a second compensation electrode, is a complex process to measure properly even in lab conditions. This just can t be corrected in the field with a simple mathematical factor. Sensors used with the FX-300 do not require such compensation, and are capable of measuring ammonia in the presence of 20 to 30 ppm potassium ions, or nitrate as low as 1 ppm in the presence of up to 400 ppm chloride ions, while maintaining linearity and stability. Such high selectivity over chloride is necessary in many secondary municipal wastewater applications to make nitrate measurement useful. Conversion Table for Logarithmic Ammonia pnh4 to ppm Ammonia ppm ppm ppm ppm ppm As shown in the graph, the FX-300-NH4 sensor performs nearly identically to the ideal response (as shown with the no potassium ions present plot with red squares) in the presence of the 20 ppm potassium even at low levels of ammonium. For the primary range of interest (as shown in blue square bracketed area) the deviation from ideal response for the FX-300- NH4 sensor even in the presence of 20 ppm potassium is altogether negligible whereas the deviation from the competitor sensor in this same area is quite prominent, with poor linearity and large deviations from the ideal response.

4 Compensation For ISE Electrodes Is Not a Valid Solution (continued) The linear response plot of our nitrate sensors in the presence of chloride at such concentrations and in the complete absence of chloride at such concentrations is statistically identical in terms of absolute response and slope (sensitivity).this means that chloride ion interference can be ignored when measuring nitrate under the most common conditions found in nitrification and denitrification monitoring processes. Description & Options: Standard system includes the universal power supply, the measurement transmitter(s) in a 9 x 11 NEMA 4X enclosure that can be wall or pipe mounted. alarm/controller and ph compensation modules are optional. The ISE modules in the FX-300 include measurement and temperature transmission, integral temperature compensation, LED display of ppm or temperature, and configurable 0/4-20mA output of ppm or temperature. Sensors are supplied as standard with a 10-ft cable with tinned lead ends, and feature industrial grade construction with the best reference lifetime in process industry through nonporous cross linked conductive polymer. Sensors are available with a protective guard and can be mounted inline in a pipe tee, immersion mounted in a tank, or submerged in a basin. A variety of waterproofing options are available to suit almost any application.

5 Description & Options: Measurement / Transmitter Modules: Modules are available to measure ph, ORP, mv, Temperature, Conductivity, Ammonium ion NH4+, Ammonia Nitrogen NH3-N, Nitrate NO3-, Nitrite NO2-, Calcium (used as a proxy for water hardness), Potassium, Perchlorate, Chloride, and Sodium among other ion selective parameters. Each module includes a 3-digit display, (6) LED s for setup and value display, and a single scalable 0 / 4-20mA output. All analog outputs have built-in trim calibration support, including both offset and span adjustments. Calibration of temperature element is available for all measurement modules. Preamplifier Support: Unlike many low cost systems, the FX-300 series supports optional external sensor preamplifiers for operation in noisy environments. It also eliminates the need to open the analyzer enclosure for sensor service, thus preventing accidental damage to the analyzer. Sensors with preamp can be located up to a maximum 300 feet away. Available only at time of order. FX-REL Option: Alarm and relay controller module with two independent configurable limits. One module required for each measurement module. Providing (2) each 250VAC / 5 amp dry contact relays with hold function for sensor calibration, and control functions that are fully configurable for control mode and variables for each control algorithm. Control modes include: 1) Alarm functions only; 2) On/Off control with a userconfigurable dead band; 3) Time proportional control; 4) Proportional frequency control (variable pulse controller). Alarms include configurable startup timer and reaction timer to avoid alarming if limits are exceeded for a short time. FX-USB Data Logging Option: Removable single or dual channel USB data logger Windows compatible software to configure, graph, or export data to other applications. FX-TP Option: Temperature output module. Transmits a 0/4-20mA output of the PT100/PT1000 temperature element. FX-TOT Option: Computes ph compensated total unbound free ammonia measurement using the free ion activity, ph and temperature as inputs; and sends the computed value by 4-20mA output. The inputs can also be sent by RS485 Modbus digital output along with the computed total unbound ion value.

6 Modbus Option: Available by ordering the measurement module to include RS485 Modbus (only on initial order), or by adding the separate FX-TM module anytime. Modbus outputs from the FX-300-TM module can consist of the ISE measurement, ph, and temperature, or the ISE measurement, ph, and a third input which can be conductivity, or a second ph/orp or ISE measurement that does not require ph compensation. Power: Universal 115/230 VAC power supply or a dedicated 24VDC power supply (not 2-wire loop power). Suitable to power up to (8) measurement / function modules. General Sensor Specifications (Additional sensors are available for other ph ranges and applications) Combination Ammonium Ion Selective Sensor: Concentration Range: 1 to 5 X 10-6 Molar, (18,000 to ppm) Lowest Limit of Detection: 2X10-7 Molar,.004 ppm ph Range: 2.5 to 9.0 ph (2.5 to 11.0 ph with FX-TOT module) Temperature Range: 5 to 40 o C Pressure Range: 1 to 10 psig Body Materials: CPVC, Ultem Junction: HDPE Reference System: Double junction, Porous Ceramic & Porous HDPE, each saturated KCl in cross-linked polymer Configuration: 3/4-3/4 MNPT, 3/4-1 MNPT, 1 MNPT Twistlock Interfering Ions (in permissible ratios of Molar excess): Interfering Ion / (Measured Ion in Molarity): Na+ (5X10 3 ), K + (10), H + (1X10 5 ) Combination Nitrate Ion Selective Sensor: Concentration Range: 1 to 5 X 10-5 Molar, (62,000 to ppm) Lowest Limit of Detection: ppm (80 ppb) ph Range: 4 to 9.0 ph Temperature Range: 5 to 40 o C Pressure Range: 1 to 10 psig Body Materials: CPVC, Ultem Junction: HDPE Reference System: Double junction, Porous Ceramic & Porous HDPE, each saturated KCl in cross-linked polymer Configuration: 3/4-3/4 MNPT, 3/4-1 MNPT, 1 MNPT Twistlock Interfering Ions (in permissible ratios of Molar excess): Interfering Ion / (Measured Ion in Molarity): ClO4- (0.006), I - (0.42), Br - (74), NO2- (219), Cl - (2,754) Combination Nitrite Ion Selective Sensor: Concentration Range: 1 to 5 X 10-5 Molar, (46,000 to ppm) Lowest Limit of Detection: ppm (276 ppb) ph Range: 4 to 9.0 ph Temperature Range: 5 to 40 o C Pressure Range: 1 to 10 psig Body Materials: CPVC, Ultem Junction: HDPE Reference System: Double junction, Porous Ceramic & Porous HDPE, each saturated KCl in cross-linked polymer Configuration: 3/4-3/4 MNPT, 3/4-1 MNPT, 1 MNPT Twistlock Interfering Ions (in permissible ratios of Molar excess): Interfering Ion / (Measured Ion in Molarity): SCN - (5), ClO4 - (25), Br - (230), NO3 - (760), Cl - (6,400) Important Notes: All linear measurement ranges for ISE sensors are given in the absence of any interfering ions. For a specific measurement range of interest for a given background of interfering ions, you should consult the factory for recommendations. Likewise, sample points in the process must be selected carefully to avoid ISE sensor damage caused by unbound sulfides, please contact the factory for assistance. FX-300 Nitrogen4 brochure