Batch studies and Effect of Environmental parameters on microbial degradation of perchlorate using acclimatized effluent sludge

摘要

Perchlorate (ClO_4~-) is a soluble anion which is widely used in explosive industries, rocket fuel manufacturing plants, demilitarization of weaponry and so on. It causes serious health implications in human by impairing the function of thyroid gland.Hence there is an urge to develop technologies for perchlorate remediation in contaminated sites or contaminated water. Present work deals with the laboratory scale study of perchlorate degradation using an acclimatized effluent sludge and the effect ofvarious environmental parameters on its degradation. Anaerobic biodegradation of perchlorate was carried out in a laboratory scale batch reactor using a mixed microbial consortium. Perchlorate reduction was monitored through routine analysis of parameters like pH, oxidation-reduction potential (ORP), salinity, CIO4 concentration using ion selective electrode and mixed liquor suspension solid (MLSS) levels. Perchlorate degradation in the absence of nitrate was more rapid compared to cells grown on perchlorate and nitrate mixture. The optimum pH and salinity for the reductive bioremediation by perchlorate enriched microbial consortium was found to be 8.0 and 0.25% NaCl. The stochiometric requirement level of ClO_4~- to acetate for the effective degradation was found to be in 1:2 ratio.