Biogas production and composition optimization in an anaerobic digestor using cheese whey and swine manure as substrate

Abstract

The search for new sources of energy has intensified these days due to the environmental impacts caused by fossil fuels. The tripod composed of energy, food and water is the base of human existence. Food production implies the generation of organic waste and the need to manage it properly. The dairy and pig farming sectors have an essential role in the Brazilian economy, producing a large amount of waste. One energy and environmental alternative to treat this issue is anaerobic digestion. Here we aimed to optimize the production and composition of biogas obtained from cheese whey and swine manure. Batch-scale laboratory tests were performed on bench anaerobic digesters for 65 days with 6 triplicates loaded with different proportions of cheese whey and swine manure. The proportion of 50% cheese whey and 50% swine manure presented the highest biogas production and methane concentration (CH₄).