Anaerobic digestion is one of the methods through which biogas is produced. Biogas can be produced utilizing anaerobic digesters. Here, the plants can be fed with energy crops such as maize silage or biodegradable wastes including sewage sludge and food waste; whereas, the landfill gas is produced by organic waste decomposing under anaerobic conditions in a landfill. Gober Gas is the other form of biogas generated out of cow dung. This type of biogas is produced mainly in the households of India and Pakistan.
Biogas has many advantages over other alternative fuels. One of the main advantages of biogas is that the technology is cheaper and much simpler than those for other biofuels. Recovery of the methane is spontaneous as the gas automatically separates from the substrates. Dilute waste materials can be used as substrate. In the process of making biogas, organic pollutants are removed from the environment and used to generate useful biogas and this actually cleans the environment. Aseptic conditions are not needed for operation. Other advantage of biogas is that it will not produce any unpleasant odours. Electricity can be generated with biogas 24 hours a day. There is reduced risk of explosion as compared to pure methane and any biodegradable matter can be used as substrate for producing biogas.
As it has many advantages, biogas too has few disadvantages as well. One among them is that the product (biogas) value is rather low and this makes it an unattractive commercial activity. This process is not very attractive economically (as compared to other biofuels) on a large industrial scale. Biogas contains some gases as impurities, which are corrosive to the metal parts of internal combustion. Other major disadvantage of biogas is that its yields are lower due to the dilute nature of substrates.
Nevertheless, Biogas can become a great substitute for other conventional energy sources.
Clifton is a qualified mechanical engineer committed to finding alternative fuel sources that can be incorporated into everyday life.