Methane production from anaerobic digestion of dairy grease trap waste: Effect of sugarcane bagasse addition

Abstract

Lipids are attractive substrates for anaerobic digestion due to their high methane production yield. However, high concentrations of lipids may cause problems in anaerobic processes. Typically, grease trap waste is mechanically removed and discharged, both generating environmental issues and wasting a potential energy source. In this study, grease trap waste from a dairy wastewater treatment plant was subjected to anaerobic digestion. Untreated and pretreated sugarcane bagasse was evaluated as fat adsorbents to reduce the inhibitory effect of the fatty waste. The bagasse pretreated by the organosolv method was the condition that most contributed to increased methane production (82%) from anaerobic digestion of dairy fatty waste at 0.5 g COD.g–1TVS concentration. Untreated bagasse provided the second-best condition, followed by hydrothermally treated bagasse, presenting no statistical difference. The obtained results showed the potential of using sugarcane bagasse as a strategy to reduce the inhibitory effect of the fatty waste from the dairy grease trap, making this waste another possible source for generating biogas.