The main constituent of biogas is methane, which makes up about 50-75% of the gas. Other components include carbon dioxide, hydrogen, and trace amounts of other gases. Biogas is produced by the anaerobic decomposition of organic matter, such as manure, sewage, and food waste. The process of anaerobic digestion produces a number of beneficial effects, including the reduction of greenhouse gas emissions, the production of a renewable energy source, and the treatment of waste.
Oxygen is not a major constituent of biogas. It is a gas that is essential for aerobic respiration, which is the process by which cells produce energy in the presence of oxygen. However, anaerobic respiration, which is the process by which cells produce energy in the absence of oxygen, is the process that produces biogas.
Acetic acid is a weak organic acid that is found in vinegar and other fermented foods. It is not a major constituent of biogas.
Methyl alcohol is a flammable liquid that is used as a solvent and fuel. It is not a major constituent of biogas.