Enhancing Wastewater Ammonia Treatment Using a Colorimetric Ammonia Analyzer
Engineers at municipal wastewater treatment plants responsible for the removal of ammonia will find the versatile colorimetric ammonia analyzer to help them confidently protect water quality reuse systems, groundwater recharge ponds, and surface water systems prior to discharge. Prolonged exposure to ammonia is toxic to aquatic life. The Environmental Protection Agency (EPA) recommends limiting NH3 to 0.02ppm in freshwater or marine environments. Within this limit, the total ammonia content can range from 160 ppm at a pH level of 6 and a temperature of 41°F (5°C) to 0.06 ppm at a pH level of 9 and a temperature of 77°F (25°C). Sewage treatment plants often use nitrification to remove ammonia. Nitrification is a two-step process of removing ammonia from wastewater using two different types of autotrophs, these oxidize ammonia to nitrite (nitrite) and then oxidize nitrite to nitrate (nitrification). Ammonia analyzers help plant technicians determine the effectiveness of treatment processes before wastewater is discharged. Ammonia analyzers with adjustable cycle times reduce disposal costs by minimizing the use of consumable reagents while still getting the job done efficiently. Technician time is also reduced, freeing up staff for other important tasks. The ammonia nitrogen analyzer is an online sequential sampling analyzer. It automates controlled sampling, analysis sequences, and then performs and repeats result processing using colorimetric methods and reagents. Colorimetric methods for water analysis rely on LED light sources and heated cuvettes designed for the measurement of trace amounts of ammonia in water. The multi-function ammonia nitrogen colorimetric analyzer can be configured to measure ammonia or a variety of other substances, and multiple parameters can be selected: ppb, ppm and mg/L. It can measure ammonia in a wide range from trace 0 to 50mg/L. Three ammonia measurement ranges are provided: 0 to 1.0 mg/L, 0 to 10 mg/L and 0 to 50 mg/L. The ammonia colorimeter performs two measurements in one analysis cycle. The second measurement is the original sample, which sets the baseline for compensation of the color, turbidity and optical properties of the cells. A second measurement is taken after the color forming reagent is added to the sample, mixed, and sufficient time has elapsed to allow the color to develop. The concentration is calculated using the difference between the two absorbance measurements and the calibration information stored in the analyzer. The Ammonia Colorimetric Analyzer is equipped with a graphical touch screen interface that displays measured values and status information. It provides users with easy access to menus and functions in multiple languages. Onboard integrated data logger with USB download capability for history tracking. The main screen of the display shows measurement parameters, status, volume percent of reagents, time and menu options. The on-screen help menu includes information on startup, shutdown, start/stop commands, calibration, function list, programming, maintenance and troubleshooting. The outputs provided by the ammonia analyzer include two 4-20mA outputs for measurement data, it also includes a Modbus compatible RS485RTU. Four programmable SPDT relays can be used to provide an alarm function. The Ammonia Colorimetric Analyzer is designed with two compartments to separate critical electronics from the wet process. The standard model is recommended for indoor use and meets NEMA IP54 dust and water resistance. The operating temperature range of the ammonia analyzer is 41 to 113°F (5 to 45°C).