Nitrate removal from ground water through lab scale bioreactor using dissimilatory nitrate reducer Bacillus weihenstephanensis (DS45)

Abstract

The study has been attempted as a combined process to treat groundwater contamination with nitrate through lab scale bioreactor using dissimilatory denitrifying bacterium Bacillus weihenstephanensis (DS45) and chemical treatments by alum and lime. Nitrate removal was attained up to 80.04% at 156 h by bioreactor process. The residual nitrate, nitrite, ammonium and bacterial growth were effectively removed by addition of lime at 150 mg/L as active coagulants. The treated sample was applied to various disinfectants such as boiling, membrane filtration, UV radiation and chlorination in order to remove bacterial biomass. The bacterial cells of 17 × 104 CFU/ml was completely removed by various disinfectant methods.