AWWA WQTC71614

This powerpoint presentation begins by providing a brief overview of ammonia and biological treatment. Study objectives were to: characterize a full-scale biologically active filter using molecular techniques to identify major genera present and determine those responsible for nitrification; design and operate pilot filters under controlled conditions to evaluate the role of operational conditions on functionality; and, observe microbial population changes in response to operating conditions in the pilot filters. Methods: ICP-MS and ICP-AES; SmartChem-Colorimetry; EM, XRD, EDS; and, benchwork. Molecular methods: culture-independent 16s rDNA gene (11F, 1492R), Ammonia monooxygenase gene (AOB and AOA), Aerobic arsenite oxidase gene; and, culture-dependent HPC, E. coli, enteroccoci, aerobic endospores, and arsenite oxidizers. Biological active filtration was found to be an efficient and sustainable technology for treatment of source waters with elevated ammonia: rapid recovery from backwash; insensitive to changes in operating conditions; oxidize ammonia >90% with complete conversion to nitrate; no pathogenic organisms/indicators; lower operating costs; nitrosomonas and Nitrospira are the major genera involved in nitrification; and, 79% of 16s diversity driven by singletons, 44% in amoA. Includes figures.