Methane Fermentation (Anaerobic Digestion)

Methane fermentation is a process where anaerobic microorganisms decompose organic matter in oxygen-free conditions, producing biogas (methane and CO2). Livestock manure, food residues, and sewage sludge serve as feedstock. The biogas generates electricity and heat; post-fermentation residue returns to farmland as liquid fertilizer. It is a circular technology yielding energy and fertilizer from waste simultaneously. Applied to wastewater treatment at food factories and breweries, it demonstrates fermentation's contribution to both food production and environmental conservation. In Japan since the 2010s, biogas plants using wastewater from food factories and breweries have been built across the country. This technology converting fermentation byproducts into new energy embodies fermentation's philosophy: there is no waste, everything is a resource.