Bacterial removal of nitrate, nitrite and sulphate in wastewater

Solutions of various concentrations of NO sub(2) super(-), NO sub(3) super(-) or SO sub(4) super(2-), and equal concentrations of NO sub(2) super(-) + NO sub(3) super(-) and NO sub(2) super(-) + NO sub(3) super(-) + SO sub(4) super(2-) in thrice distilled water as well as in samples of industrial wastewater effluents of Kima company (a factory producing ammonium nitrate coated with limestone powder fertilizer) at Aswan City and River Nile water collected from Mansoura, Damietta, Kafr El Zayat and Edfina were tested against Bacillus Stearothermophilus Asw 88 and Bacillus Stearothermophilus Asw 129 and autoclaved at 37 and 50 degree C for various hours using nutrient yeast extract (NYE) medium. Detection and assay of NO sub(2) super(-), NO sub(3) super(-) and SO sub(4) super(2-) in simple salt solutions using NaNO sub(2), NaNO sub(3), Na sub(2)SO sub(4) and H sub(2)SO sub(4) after screening for 120 h indicates complete depletion of these components as they are good and convenient essential nutrient sources for both strains utilized safely for the treatment of polluted water. The strains are not pathogenic and they have no hazardous effect on human and animal life. The method is efficient and the results of the analysed water samples are consistent with the permissible safety baseline levels desired for domestic, irrigation and industrial purposes and also for drinking purposes after disinfection according to the World Health Organisation Standards.