Effluent treatment process in molasses-based distillery industries : A review

Distillery effluent is a contaminated stream with high chemical oxygen demand (COD) varying from 45,000 to 75,000 mg/l and low pH values of between 4.3 and 5.3. Different processes covering aerobic, anaerobic as well as physico-chemical methods which have been employed to this effluent has been given in this review paper. Among the different methods available, it was found that "An Inverse Anaerobic Fluidization" to be a better choice for treating effluent from molasses-based distillery industries using an inverse anaerobic fluidized-bed reactor (IAFBR). This technology has been widely applied as an effective step in removing 80-85% of the COD in the effluent stream. Therefore, in this review, attention has been paid to highlight in respect of fluidization phenomena, process performance, stability of the system, operating parameters, configuration of inverse anaerobic fluidization and suitable carrier material employed in an inverse anaerobic fluidized-bed reactor especially for treating this effluent.