Treatment of rice grain-based distillery effluent using hybrid electro-coagulation–microfiltration processes: performance and optimization

The distillery industry has tremendous contribution to the Indian economy. Nowadays poor grade rice grain is used as a raw material for alcohol production instead of sugarcane molasses due to its availability throughout the year. However, wastewater generated from the distillery industry creates a serious effect on humans, plants, and animals. The biodigester effluent (BDE) generated from the rice grain-based distillery industry has a high organic load in terms of the chemical oxygen demand (COD = 7,020 mg/dm3) and color appearance (color = 485 PCU). Present work is an attempt to treat BDE by using electrocoagulation (EC) and electrocoagulation followed by microfiltration (EC-MF) processes. The maximum COD removal of 98.6% and color removal of 99.9% were achieved by the EC-MF process at their optimum condition. On the other hand, maximum COD removal of 87% and 80% were achieved with individual EC and MF processes respectively. The zero discharge is the need of the distillery industry therefore the EC-MF process is well applicable to treat BDE.