Co-Digestion of Cattle Slurry and Waste Milk under Shock Loading Conditions

Anaerobic digestion of cattle slurry has become a well established practice. In recent years disposal of waste milk in the UK has been the cause of many pollution incidents. This paper describes the co-digestion of cattle slurry and waste milk under shock loading conditions in 1 dm3 laboratory digesters. Methane concentration in the biogas of all digesters receiving waste milk additions initially dropped, but quickly recovered to above previous levels. The methane production rate (dm3 methane day−1) was most elevated in those digesters receiving the greatest loading of waste milk; however, initial depression of biogas methane concentration was also greatest in this system.