Elliptical soft biogas digester is a common biogas fermentation equipment, which has the advantages of simple structure, large volume and small footprint, and is suitable for rural families or agricultural production units. The following describes how to construct an elliptical soft biogas digester.
Design site: Choose a place with sufficient sunlight, good drainage, and away from living areas and livestock farms to ensure the normal operation and use of the biogas digester.
2.Foundation construction: According to the design requirements, excavate an oval-shaped foundation pit, and the depth of the foundation pit is generally 15-2 meters with a width of 15-2 meters. The bottom of the foundation pit should be flat and solid, and a layer of sand or cement mortar can be laid as a foundation.
3.Biogas digester wall construction: The wall of the biogas digester can be constructed with cement bricks, mortar or reinforced concrete. First of all, a circle of wooden formwork is built around the foundation pit, and then concrete or mortar is poured into the formwork to gradually form the wall of the biogas digester. The height of the wall is generally 15-2 meters with a thickness of 15-20 cm.
4.Biogas digester top construction: A steel plate or plastic film is installed on the top of the digester to cover the digester and prevent gas leakage. The size of the steel plate or plastic film should match the size of the top of the digester, which can be fixed to the wall of the digester using bolts or welding.
5.Biogas inlet and outlet construction: Two holes are dug in the wall of the biogas digester, one for the biogas inlet and the other for the biogas outlet. The biogas inlet is generally located at the top of the digester and is used to introduce the biogas produced by the fermentation materialThe biogas outlet is generally located at the bottom of the digester and is used to discharge the biogas. The size and location of the inlet and outlet holes should be determined according to the design requirements, and valves or pipes need to be installed to connect other equipment.
6.Construction at the bottom of the digester: Lay a layer of plastic film or cement mortar at the bottom of the digester to prevent biogas leakage and leakage. At the same time, a sewage hole can also be set at the bottom to discharge biogas residue and wastewater.
7.Sealing treatment of biogas digester: In order to prevent biogas leakage, a layer of rubber film or tape can be installed on the wall and top of the digester, and it can be sealed with glue or tape. In addition, valves or seals can be installed at the inlet and outlet of the biogas to ensure the tightness of the biogas.
8.Start-up and maintenance of the digester: After the construction of the digester is completed, the fermentation material needs to be put into the digester, and the appropriate amount of water and fermentation bacteria are added, and the biogas can be generated after a period of time.