Performance evaluation and intensification of novel buoyant filter bioreactor with associated secondary treatment process for rice processing industries

Rice being the staple food of a larger population in general and to the India in particular and most of the industries are adapting the parboiled process. Rice production by parboiled process required large amount of water and discharging huge amount of wastewater to environment. Thus, most of the rice industries were falling under red or orange category of highly polluted industry. In this context the present study was undertaken to evaluate the performance of an ETP at rice processing industry. The ETP employed a primary high rate anaerobic treatment system called Buoyant filter bioreactor (BFBR) followed by secondary chemical treatments, to meet the effluent standards. The overall percentage removal efficiency of ETP observed is COD (90%), Colour (93%), Iron (100%), phosphate (100%), turbidity (94%), TSS (50%) and BOD (99%). A sharp reduction of BOD from 1500 to 10 mg/l was observed upon BFBR treatment indicating the excellent working condition of BFBR. The final effluent coming out from ETP meets the criteria for Permissible Limit as per ISI,1977 (On land of irrigation) and Permissible Limit as per ISI 1974 (In land surface water) which indicates the performance of the developed ETP is satisfactory.