AWWA WQTC65705

This powerpoint presentation begins by providing a brief overview of the use of chloramination, nitrification mechanisms in chloramine system, and conventional nitrification control strategies. The objectives of this study were to: establish a kinetic inhibition model on Nitrosomonas europaea at low levels of chlorite (<0.40 mg/L as ClO₂ ^-) based on ammonia-oxidizing bacteria (AOB) activity; and, compare the activity and viability of the AOBs in response to chlorite inhibition. The experimental design is provided, along with model development, and results and discussion. The summary states that: chlorite concentration at 0.02-0.4 mg/L can completely inhibit the N. europaea within 6-72 hours, depending on the environmental conditions; and, based on the modeling and PCR results, they are suggested that the presence of chlorite impact activity rather than viability of the cells. Includes table, figures.