Total Kjeldahl Nitrogen (TKN) is comprised of which components?

Total Kjeldahl Nitrogen (TKN) is a measurement used to assess the total nitrogen content in a sample, specifically reflecting the organic and inorganic nitrogen fractions present. The correct components of TKN are organic nitrogen and ammonia.

Organic nitrogen represents nitrogen that is part of complex organic molecules, typically associated with proteins and amino acids found in biological materials. Ammonia, on the other hand, consists of the ammonia nitrogen that is liberated during the digestion process that TKN testing employs. The digestion process converts organic nitrogen into ammonia, allowing it to be quantified together.

This combination provides a comprehensive view of nitrogen present in wastewater, excluding forms like nitrate and nitrite, which are measured separately in other methods. Thus, TKN focuses specifically on the organic portion and the ammonia, making the understanding of nitrogen dynamics in wastewater treatment processes crucial for lab analysis and water quality management.