Biogas: A waste-to-energy solution

As a renewable energy, biogas is naturally produced from organic wastes such as animal manure, wastewater treatment residues, municipal and industrial food waste, and sewage sludge. This waste-to-energy decomposition process usually takes place in an environment absent of oxygen, known as anaerobic digestion. It is a biological process through which bacteria break down biodegradable materials, releasing a mixture of gases, primarily methane and carbon dioxide.

Biogas anaerobic digestion

Compared with traditional methods such as composting, anaerobic digestion is a more environmentally friendly and sustainable approach to converting organic wastes into bioenergy. The anaerobic digestion system allows microorganisms to convert organic residue of sludge and waste treatment into biogas through biological fermentation. A typical biogas digester entails a system capable of mechanical mixing, heat exchanging, and separation through a centrifuge or sludge press. The remaining liquid can be recycled for slurry pre-treatment, and the non-digestible sludge can be used as raw materials for fertilizers.

Benefits of biogas production

Biogas production reuses organic resources to produce bioenergy for the production of electricity and heat. Simultaneously, it digests and converts organic materials into fertilizers or soil conditioners in the form of nutrient-rich sludge, which results in fewer CO2 emissions and fewer waste materials. Most importantly, biogas can be purified and upgraded to renewable natural gas and thus be used as automotive fuels or in natural gas networks.