Basic Wastewater Operator Practice Exam

Total Kjeldahl Nitrogen (TKN) is comprised of which of the following?

1. Phosphorous and nitrogen

2. Nitrogen, oxygen, and magnesium

3. Nitrogen, potassium, and ammonia

4. Organic nitrogen and ammonia

The correct answer is: Organic nitrogen and ammonia

Total Kjeldahl Nitrogen (TKN) is an important measure in wastewater treatment that quantifies the total concentration of nitrogen present in a sample. Specifically, TKN includes two main components: organic nitrogen and ammonia nitrogen. Organic nitrogen refers to nitrogen that is part of organic compounds, which come from various sources including proteins and amino acids found in living organisms and their waste products. On the other hand, ammonia nitrogen refers to nitrogen in the form of ammonium ions (NH4+) that can be readily available for biological processes. Measuring TKN provides insight into the nitrogen content that can affect aquatic life when released into environments, as excessive nitrogen can lead to problems like eutrophication. In contrast, the other options include components that do not accurately represent what TKN measures. Phosphorous, oxygen, and potassium are not included in the Total Kjeldahl Nitrogen assessment. Therefore, the option that correctly identifies the components of TKN is the combination of organic nitrogen and ammonia.