It is called biogas to the gas which is obtained from the decomposition of type waste organic by anaerobic route (that is, without oxygen). This process is developed by bacteria.
Biogas, therefore, is a fuel generated by the degradation of organic substances . The anaerobic decomposition that microorganisms perform allows producing biofuel with the treatment of biodegradable waste. Process effluents, on the other hand, serve as fertilizer .
He methane and the carbon dioxide they are the main constituents of biogas, which also has nitrogen , hydrogen and other elements. With biogas you can generate the Energy They use boilers, stoves, ovens and other devices, and it is even possible to produce electricity using a generator.
He system which takes advantage of the digestion of bacteria found in manure for the generation of biogas and fertilizer is called biodigester . In its simplest format, a biodigester is a container known as reactor , where the organic substances that will ferment are stored. In the reactor, which is impermeable and closes tightly, waste from plants and animal feces can be included so that, with anaerobic fermentation, biogas and fertilizer are generated.
The building of a biodigester is very simple and economical. That's why in rural regions of Latin America the development of these reactors is promoted to obtain biogas, whose combustion generates little smoke. Farmers, in this way, can produce their own energy at a reduced cost.
To produce biogas through the digestion Anaerobic organic matter is necessary to carry out a process consisting of four well-defined stages, as indicated by experts in biochemistry and microbiology who are engaged in this activity. The procedure is presented in detail below:
* hydrolysis : It is the first stage of biogas production, and requires that organic compounds pass through the cell wall so that its organic matter can be harnessed. It is possible to obtain organic compounds soluble from polymeric organic matter thanks to the action of hydrolytic microorganisms, which generate extracellular enzymes that have such capacity. The time it takes for the entire process is largely determined by this stage, whose success is linked to the dimensions of the particles, the temperature, the biochemical composition of the substrate and the pH, among more factors;
* acidogenesis : At this stage the conversion of soluble organic molecules into three types of compounds takes place. They are divided into those who cannot take advantage of bacteria methanogenic (such as fatty acids, aromatic compounds and ethanol), and those that do (where we find hydrogen, acetic and formic, in addition to propionic, valeric and lactic). These compounds are also responsible for eliminating any trace of oxygen in the biodigester;
* acetogenesis : Any compound that could not be metabolized by methanogenic bacteria is used at this stage, and among them are aromatic, fatty acids and ethanol, which are transformed into others of less complexity, such as hydrogen and acetate . Homoacetogens also stand out here, a very particular type of acetogenic microorganism that is capable of generating acetate and is used to keep hydrogen gas below, since it does not produce it;
* methanogenesis : to complete the anaerobic decomposition of the products, they enter action methanogenic bacteria, which are responsible for producing methane. It is known that 70% of the methane produced in biodigesters arises when acetic acid loses the carboxyl group of atoms, since acetate can only be used by two genera of bacteria.