The name ‘Biogas’ is commonly used to refer to a gas which has been produced by the biological degradation of organic matter.
Anaerobic Digestion is a microbiological process for decomposition of organic matter, in the absence of oxygen, common to many natural environments and largely applied today to produce biogas in airproof reactor tanks, commonly named digesters. A wide range of micro-organisms are involved in the anaerobic process which has two main end products: biogas and undigested residue. Biogas is a combustible gas consisting of methane, carbon dioxide and small amounts of other gases and trace elements. Residual substance is the decomposed substrate, rich in macro- and micro nutrients and therefore suitable to be used as fertilizer.
Usage of Biogas
Biogas can be used as primary source of energy to cater our ever increasing energy needs in various sectors some of them can be described as following
Electric Power Generation:- Biogas be used to generate electrical power as well as heat can be produced with the help of simple conventional gas fueled generator. The proportions of heat and power generated depend of course on the design of the plant but generally the chemical bond energy present in biogas can be converted into 35 percent electricity and rest of 65 percent into heat.
Bio-CNG (Vehicular Fuel): – Biogas can be upgraded to produce Bio-CNG so as to make it usable as vehicular fuel in transportation sector to replace the Mineral CNG. The biogas from a Digester is purified up to desired level and compressed up to 200 Bar, what is called the Bio-CNG, ready to use as alternative fuel for automobile vehicles.
Biogas in the gas network: – As per recent developments in Govt. Policies Refined biogas (Bio-CNG) can be injected into existing gas (CNG or PNG) networks. Functioning networks with natural gas are being used for gas cookers, heaters, baking ovens, water heaters in many towns.
Biogas in Industry: – Many industries such as Sugar Mills, Refineries, Distilleries, Dairies and paper mills generate processing Waste which can be used as a source of feed stock for AD plants and digested directly on site. The biogas created can then be used on site for heating premises, district heating, power production and any heat requirement.