What is Total Nitrogen?

Total Nitrogen or Total Kjeldahl Nitrogen (TKN) is the U.S. EPA approved parameter, used to measure organic nitrogen and ammonia. Total nitrogen is the sum of Total Kjeldahl Nitrogen (ammonia, organic and reduced nitrogen) and nitrate-nitrite. It can be derived by monitoring for organic nitrogen compounds, free-ammonia, and nitrate-nitrite individually and adding the components together. The TKN content of influent municipal wastewater is typically between 35 and 60 mg/L.

Total nitrogen measurement may be determined using on-line instrumentation or by using portable/laboratory water analysis. The Proam ammonia monitor provides continual on-line measurement of the ammoniacal-nitrogen using a gas sensing ion selective technique. The summation of nitrate and nitrite may be determined by the TriOS NICO sensor or individually by the OPUS sensor technology.