Ammonia sensor and nitrate sensor with improved selectivity over critical interfering ions for municipal wastewater Treatment Plants - Case Study
- Capability to measure below 1ppm ammonium (total ammonia or NH3-N) in presence of common levels of potassium for secondary WWTP
- Capability to measure nitrate (NO3-N) even in the presence of high levels of chloride or nitrite ions without loss of linearity or stability
- Ammonia and nitrate measurements can be performed using just one analyzer
- Support for dual ammonia/ammonia, nitrate/nitrate configurations and ammonium/nitrate configurations to minimize cost per channel as well as triple channel ISE, pH and ORP measurement configurations
- No potassium ion 'compensation' required for ammonium ion selective sensors and no chloride ion 'compensation' required for nitrate ion selective sensors for most common WWTP applications, due to substantial improvements using novel proprietary technology developed from ASTI research and extensive field trials to ensure performance in actual measurement conditions of interest
- Support for dual ammonium/pH systems to determine total ammonia at any given pH for any given temperature within the permissible range
The measurement of ammonium ions (commonly referred to as “total free ammonia”) at low levels, such as below 1 ppm, can be difficult with many competing sensor technologies. Competitors using older traditional ISE membrane technology grapple with a well-known problem due to the effects of the interfering ion potassium at the concentration in which they are commonly present. The “solution” that is promoted by many competitors is to employ a second ion selective sensor to measure the interfering potassium ion activity and then to 'compensate' for the effects of the potassium ion error upon the ammonium sensor.