ABSTRACT
Molasses-based alcohol producing distillery industries are growing promptly nowadays due to the high demand for alcohol in various industrial sectors. During alcohol production, distillery industries produce melanoidin containing brown-colored effluent called spent wash as wastewater. This wastewater contains a high amount of chemical oxygen demand (COD) and is highly acidic in nature. Due to this reason, it causes pollution in both land and water, so it creates the most critical environmental issues. A number of chemical, physical and biological systems were developed for the treatment of distillery spent wash (DSW). But among all of them, anaerobic digestion is very effective for primary treatment because it is low cost, environment friendly and economically acceptable. It can reduce COD faster than other techniques. However, the impurities cannot completely cast off from DSW after anaerobic treatment; sequential treatment with several aerobic methods could provide a link in the process. Potent aerobic microorganisms can reduce color as well as COD very meritoriously. Moreover, with the help of microorganisms and DSW as a substrate, various value-added products could be achieved, which would make it economically significant and valuable for relevant industries.
