Performance Evaluation of a Full Scale Effluent Treatment Plant for Distillery Spent Wash

Distillery spent wash can be one of the major polluting wastewaters, if discharged into water bodies without adequate treatment. Anaerobic lagooning was the only treatment option mostly practiced by distillers to treat distillery spent wash before 1980s. Thereafter, significant development in management of distillery spent wash has been achieved in this country. Today almost all distillers recover biogas from distillery spent wash through the biomethanation process. Anaerobic digesters, anaerobic fixed film systems and two-phase anaerobic treatment are some of the treatment options popularly practiced by Indian distilleries for biomethanation. Production of biogas from spent wash not only reduces the pollutional load but also reduces the payback period of the effluent treatment plant. This paper details the performance evaluation of a full-scale effluent treatment plant for distillery spent wash. In addition, the approach that included detailed biological and physico-chemical treatability studies for improvement in treated effluent quality is also discussed.