Anaerobic Digestion Treatment of Soft Drink Wastewater

Abstract

The aim of this study was to treat soft drink industrial wastewater by anaerobic digestion. Digestion lasted for a hydraulic retention time of 30 days. The total quantity of biogas produced was 80ml. The wastewater was characterized after digestion. The result showed that chloride, total dissolved solid, total suspended solid and chemical oxygen demand met the specifications of the world health organization for the safe disposal of wastewater into the water body. The kinetics of anaerobic digestion of the wastewater was described by first order kinetic model. The net specific growth rate of the wastewater was evaluated and observed to reduce with time. The kinetic parameters such as maximum rate of substrate utilization, half velocity or saturation constant, endogenous decay coefficient, biomass or microbial growth yield and maximum specific microorganism growth rate obtained were 0.350day −1 , 204.12mg/l, 0.0222day −1 , 0.194day −1 and 0.0679day −1 respectively. This revealed that inoculation would be needed for increased volume of biogas production and for an increased digestion rate to be obtained. Based on the endogenous decay coefficient and biomass yield values, a small sludge handling facility would be required in the absence of inoculation during digestion.