If the ammonia concentration in an anaerobic digester exceeds __________, it becomes toxic.

The threshold for ammonia concentration in an anaerobic digester is a critical factor to consider because ammonia can inhibit microbial activity, which is essential for the digestion process. When ammonia concentrations exceed 200 mg/L, it starts to become toxic to the microorganisms responsible for the anaerobic digestion of organic waste. This can result in a decrease in digestion efficiency and potentially lead to system failure.

The chosen concentration of 3000 mg/L reflects a level that is recognized in the field as significantly detrimental to the operational health of an anaerobic digester. At this higher concentration, the toxicity effects are pronounced, leading to substantial disruptions in microbial function, which can halt the decomposition of waste and affect biogas production.

Understanding the mechanisms of toxicity at different ammonia concentrations highlights the importance of monitoring and controlling ammonia levels within anaerobic digesters to ensure optimal performance and effective waste treatment.