Evaluation of potential substrates for biogas production via anaerobic digestion: A review

The anaerobic digestion of organic matter is now a widely-used technology, to address both energy and environment challenges. Biogas can be produced by landfill gas (LG), or produced at sewage treatment plant, in anaerobic digestion of industrial, municipality and agricultural treatment. Biogas contains 50-70% methane and 30-50% carbon dioxide as well as small amounts of other gases, nevertheless, the quality of biogas composition is dependent on the substrate type and technology used. Thus, this paper reviews the methane yield from various feedstocks. Sewage sludge has shown positive methane yield, nevertheless its conversion may be optimized by applying co-digestion process with organic fraction municipality waste (OFMSW) as a co-substrate. Although pulp and paper mill sludge has high methane potential, the amount of methane yield is dependent on the pulp and paper process used and activated sludge plants (ASPs). Generally, methane yield from AD of slaughterhouse range between 160m³/ton kg VS- 500 m³/ton kg VS, depending on the amount of blood presented and processes used.