The main component of biogas is methane. Methane is a colorless, odorless gas. Solubility: slightly soluble in water, soluble in alcohol and ether. , density (standard conditions) 0.717 g/L, boiling point -161.5℃, melting point -182.48℃. Heat of combustion (kJ/mol): 889.5, critical temperature (℃): -82.6,
Critical pressure (MPa): 4.59. Flash point (℃): -188, ignition temperature (℃): 538. Under certain conditions, methane can undergo halogenation reactions (Cl2, Br2) and thermal decomposition (decomposition into C, H2, C2H2, etc.). Build a biogas tank with a volume of 6 cubic meters, and ferment the manure equivalent to four pigs every day. The biogas it produces can solve the fuel problem of lighting and cooking for a family of four.
Biogas can also be used in agricultural production, such as greenhouse insulation, baking agricultural products, biogas moth prevention, grain storage, fruit preservation, etc. Biogas can also be used to generate electricity to power agricultural machinery. The biogas produced by large and medium-sized biogas projects can be used to generate electricity, burn boilers, process food, heat or supply urban residents. For example, in Nanyang City, Henan Province, 30,000 urban residents have used biogas since the 1970s.
What are the benefits of building a biogas digester?
Years of practice have proven that developing biogas in rural areas is a good thing that achieves multiple goals with one stone. It can bring many benefits to the country, collectives and farmers, and is a major event in my country's rural construction. The benefits of running biogas in rural areas can be summarized in the following aspects.
First, the development of biogas in rural areas is one of the important ways to solve the fuel problem in rural areas. A family of 3 to 4 people can build a biogas digester with a volume of about 6 cubic meters. As long as the fermentation raw materials are sufficient and managed well, the problem of fuel for lighting and cooking can be solved. Wherever biogas is implemented well, the sanitary conditions and living environment of farmers have been greatly improved. In particular, through the use of biogas, the majority of rural women are freed from the smoky traditional cooking methods. Biogas production is also conducive to protecting forest and grass resources, promoting the development of afforestation, reducing water and soil erosion, and improving the agricultural ecological environment.
Second, biogas development in rural areas can change agricultural production conditions and promote the development of agricultural production.
(1) After adding fertilizer to start biogas, a large amount of crop straw and livestock and poultry manure that were burned in the past are added to the biogas tank for closed fermentation, which can produce gas and retting into high-quality organic fertilizer. , expanding the sources of organic fertilizers. At the same time, human and animal manure, straw, etc. are fermented in a biogas digester to improve fertilizer efficiency and eliminate parasite eggs and other pathogenic bacteria that endanger people's health. If biogas is done well, organic fertilizers can be doubled, and the production of grains, vegetables, and fruits can increase year after year. At the same time, the quality of products has also been greatly improved, and production costs have dropped.
(2) Enhance the ability of crops to resist drought and freeze, and produce green food. All crops that use biogas fertilizers have enhanced their ability to resist drought and freeze, and improve the survival rate of seedlings. After closed fermentation of human and animal manure and straw, while producing biogas, a certain amount of biogas fertilizer is also produced. Biogas fertilizer contains abundant amino acids, B vitamins, various hydrolases, certain plant hormones, and has obvious effects on pests and diseases. It has inhibitory effects, so it is an excellent organic fertilizer for various crops, flowers, fruit trees, vegetables, etc. It has the functions of promoting production, increasing yield, resisting cold, and resisting diseases and pests for various crops. The application of biogas fertilizer not only saves the amount of chemical fertilizers and pesticides, but is also beneficial to the production of green food.
(3) It is conducive to the development of livestock and poultry breeding. The establishment of biogas will help solve the contradiction between the "three materials" (fuel, feed and fertilizer) and promote the development of animal husbandry.
(4) Saving labor and funds. After the establishment of biogas, the large amount of labor that farmers spent in the past on collecting firewood and transporting coal can be saved and invested in the front line of agricultural production. At the same time, it saves money to buy firewood, coal, pesticides, and chemical fertilizers, allowing farmers to reduce daily economic expenses and benefit from biogas.
Third, the implementation of biogas in rural areas is conducive to protecting the ecological environment and accelerating agricultural modernization. Using biogas as power fuel, you can start a diesel engine (or gasoline engine) for pumping water, generating electricity, grinding rice, grinding flour, crushing feed, etc. The benefits are very significant and it is very popular among farmers. The fuel saving rate of diesel engines using biogas is generally 70% to 80%. Using biogas as power fuel is clean, pollution-free, easy to prepare, and low cost. It can not only save petroleum products for the country, but also reduce operating costs. It opens up new power resources for the realization of agricultural modernization and is an important energy source in rural areas. construction.
Fourth, the implementation of biogas in rural areas is a major change in health work. A key measure to eliminate parasitic diseases such as schistosomiasis and hookworm is to manage human and animal feces well. After the establishment of biogas, human and animal excrement are put into the biogas tank for closed fermentation. Parasitic eggs in the excrement can be reduced by about 95%. The environmental sanitation where farmers live has been greatly improved. Parasitic diseases can be controlled and eliminated, which is a good way to do a good job in rural pest control. Sterilization has found a new approach.
Fifth, the implementation of biogas in rural areas has promoted the development of science and technology popularization in rural areas and vividly demonstrated the huge role of science and technology in improving productivity.