Microbial Treatment of Raw and Primary Treated Sanitary Landfill Leachate by Indigenous Strain Brevibacillus agri.

Abstract

Landfill leachate is a potential environmental threat. Sanitary landfills are model sites which contains a leachate collection pool and a processing facility to treat it up to environmental standards before discharge. The present study is the very first endeavor to establish leachate treatment efficiency of indigenous microbial strain Brevibacillus agri. Leachate samples were inoculated with isolated strain and incubated for 41days in an orbital shaker. Percent reduction in major water quality parameters was assessed after 0, 7, 21, and 41days of incubation, for understanding the degradation kinetics. Results of the study demonstrate that Brevibacillus agri was effective in improving the wastewater quality of both raw and primary treated leachate. Overall reduction for different water quality parameters was found to be 50% higher for primary treated leachate than that for raw leachate within 21days of incubation. Microbial degradation followed first-order kinetics with rate constants in the range of 0.0047-0.03 and 0.0061-0.074day-1 for raw and primary treated leachate respectively. Calculated half-life of each pollutant parameter was significantly higher in the raw sample (23-147days) as compared to the primary treated one (27-112days). The leachate pollution index (LPI) value of the raw leachate was also found to be > 25% higher than primary treated leachate sample after microbial treatment. Hence, it can be concluded that on site application of primary treatment technology followed by secondary microbial degradation by indigenous microflora, viz., Brevibacillus sp., may prove effective to achieve desirable water quality for safe environmental discharge.