EFFECT OF HYDRAULIC RETENTION TIME FORTREATING DISTILLERY EFFLUENT IN DIPHASICANAEROBIC DIGESTER

Diphasic anaerobic digesters have inherent advantages of exclusive process controls on the growth of microorganisms independently in acidogenic and methonogenic phases. A laboratory model of 15.0L effective volume with 2.5L of acidogenic reactor and 13.5L of methonogenic reactor was used to evaluate the treatability of distillery wastewater stream. The model was run for varying concentrations of COD and influent rates to study the effect of hydraulic retention time in reducing the COD into unharmful end products. The COD removal efficiency is found to vary from 17.67 to 26.19 % for the acidogenic reactor under the varying HRT of 0.96 to 2.89 days and 59.51 to 77.42% with varying HRT conditions from5.21 to 15.63 days for the methanogenic reactor. The overall COD removal of the system is observed at an efficiency of 82.30% for the system HRT of 18.52 days.