A novel sequence batch treatment of wastewater using Bacillus sp. IITRDVM-5 mixing with paper mill and sewage sludge powders

Abstract

Worldwide, the release of toxic organics with liquid and solid waste from the paper industry has become a serious concern. Papermill effluent was treated by the activated sludge process using urea-diammonium phosphate (DAP) as the sources of nitrogen and phosphorous, which caused bleaching of phytoplankton and eutrophication. Aiming this, urea-DAP was replaced with paper mill sludge powder (PMSP) and sewage sludge powder (SWSP) individually for the treatment of effluent using Bacillus sp. IITRDVM-5. The use of PMSP and SWSP individually showed maximum reduction in total organic carbon, chemical oxygen demand, biochemical oxygen demand, lignin, total phenol, adsorbable organic halides, total Kjeldahl nitrogen, phosphate, and color than the final discharge of paper industry effluent at optimum conditions. IITRDVM-5 also showed a 75.0 to 82.5% reduction in different concentrations of phenol. Gas chromatography analysis of effluent treated mixing with PMSP showed complete removal of 2,5-dichlorophenol; 2-methyl-4, 6-dinitrophenol, and 94% pentachlorophenol. Finally, the effect of untreated, treated, and final discharge of effluent was studied on seed germination of Vigna radiata and effluent treated with IITRDVM-5 showed good seed-growth and lesser phytotoxicity.