Feed preparation enables the input of the organic matter / wastes to be brought to the desired size. Mix quantities of each material is also established in order to achieve the optimum “recipe”. The resulting feed is loaded in the digesters at the designed quantity and intervals by the automated feeding system.
Fermenters
In industrial biogas plants, the size and number of fermenters vary depending on the plant capacity and the hydraulic waiting time. Fermenters can be constructed from concrete or steel. In most facilities, the top of the gas tank is usually equipped with an elastic gas collection cover on the fermenter. The mixers are placed in the fermenter so that the material in the fermenter can be properly mixed. In addition, fermenters are well insulated to minimize heat loss and auto-controlled heating coils are placed in the fermenters to keep the interior temperature of the fermenter within the desired range.
Cogeneration Unit
The Cogeneration Unit is the part where the produced biogas is converted into electricity and heat. Biogas taken from the fermenter contains 50-60% CH4, 30-40% CO2, 500-2500 ppm H2S, and very small amounts of other gases and moisture. H2S in the content of biogas, combined with moisture in the gas engine, pipelines and so on causes corrosion of mechanical parts. Before the biogas is used in the gas engine, H2S and moisture in its’ content must be separated. Heat and electricity are obtained by using H2S and moisture in the separated biogas gas engines. Part of the heat generated is utilized in the heating of the materials in the fermenter, the remainder being utilized to provide heating for other facilities in the complex. While most of the electricity produced is supplied to the electricity grid, some is used to operate the equipment in the facility.
Organic Fertilizer Factory
The Digestate remaining at the end of biogas process is pumped to separators. After separation, the solids phase is sent to the Dry Organic Fertilizer Plant where it is dried to 25-30% moisture levels, before being granulated, pelleted or powdered, then hygienized before being packaged for sale. The liquid phase (3-6% solid matter) is pumped to the Liquid Organic Fertilizer Plant to be further processed to produce 30% solid matter liquid fertilizers with high humic-fulvic acid content, & packaged for sale
