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Technologies Dry fermentation (biogas)


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In dry fermentation, raw material does not have to be liquefied, which makes it suitable for organic wastes with high (up to 50%) dry matter content. The technology is based on the process "biological fermentation - methanisation." Methanisation is a process in which various types of bacteria pull down the biomass of animal or plant origin to combustible gas in oxygen-free (anaerobic) environment. The gas emitted during the process of methanisation consists mainly of methane, CH4 (up to 70%), carbon dioxide CO2 and small (less than 1%) amounts of other gases. This mixture of gases is known as "biogas" and its precise characteristics depend on the parameters under which the methanisation takes place. Biogas is burned into internal combustion engines resulting in a combined production of heat and electrical power. It is possible to enrich (upgrade) the biogas by 98 to 99% of methane, which is equal to the content of methane in the fossil gas and its possible usage as a vehicle fuel.

The main technological systems provided for the enterprise are: storing and preparation of raw materials (in accordance with the requirements of the European directives for soil protection from nitrate pollution and preventing emission of methane and hydrogen sulfide in the atmosphere), methanisation, combined production of heat and electrical power, utilization of the waste heat, processing of waste products and production of organic fertilizer.