| "Effect of potassium cyanide (KCN) on nitrification process in municipal wastewater treatment plants was studied by batch nitrification tests, which indicated that nitrification process tends to be inhibited at a lower KCN concentration than present discharge standard to sewerage. The experiment of the biosensor using nitrifying bacteria was also conducted for continuous monitoring of nitrification inhibitor in influent wastewater, and demonstrated that the biosensor can detect KCN at as low as EC10 of the abovementioned batch nitrification test. Moreover, to know the effectiveness of application of the biosensor to avoid the impact of KCN due to accidental spill in sewerage system, KCN was intentionally injected into both the experimental models of activated sludge process equipped with and without the biosensor. The model with the biosensor that could detect KCN could divert the wastewater including KCN to a refuge tank, which resulted in the avoidance of upset of the activated sludge process. On the other hand, the model without the biosensor was upset in nitrification process due to KCN. Such difference demonstrates the effectiveness of the biosensor applied to countermeasures of accidental spill of toxic chemicals to avoid upset of nitrification in municipal wastewater treatment plants." |
