Anaerobic digestion of brewery wastewater for pollution control and energy

This paper describes the operation of a pilot-scale anaerobic filter to treat brewery wastewater containing approximately 6000 mg/l of GOD. The 2600-liter pilot digester was loaded at up to 2.79 kg of COD per cubic meter of digester per day and an HRT of 2.2 days. Biogas containing 75% methane was produced at the rate of 0.39 cubic meters per kg of COD per day, and the COD was reduced by 87%. The digester was maintained at 36 degrees C. and the effluent pH was above 6.8 as long as the influent pH was adjusted to above 6.0. A full-scale system that would treat 40,000 liters of wastewater per day would have a volume of 80 cubic meters and produce 90 cubic meters of biogas per day while reducing COD by 80 to 90%. Additional aeration will be required to meet the 400 mg/l COD discharge requirement.