Biogas is a mixture of gases, mainly composed of methane (CH4), of the total volume of 50% to 70%, followed by carbon dioxide (CO2), accounting for 25% to 45%. In addition, it also contains a small amount of nitrogen (N2), hydrogen (H2), oxygen (02), ammonia (NI-I4), carbon monoxide (CO) and hydrogen sulfide (H2S) and other gases.

     Biogas with energy, ecological, environmental, economic and social multiple functions. Development and utilization of biogas technology to solve their living and production of energy, help protect resources and the environment. The promotion of rural socio-economic and ecological environmental development, and building a socialist new countryside with far-reaching significance. Biogas energy in rural areas has become an important part of the broad prospects for development.

 Advantages and disadvantages of evaluation:
 (l) from the resource recovery, utilization and commercialization of products starting Optimization related science and technology, not only to obtain higher energy, ecological and environmental benefits, and access to considerable economic benefits.
 (2) due to the convergence point of the technology section of the buffer areas are provided, running water to fully bear pig manure, water and the pH, the impact of the operation and ensure that the system can get a stable yield excellent results. Specifications and Requirements: Date header handling herds 6500-7000 100-200 tons of pig manure all the old, at about 300 cubic meters of biogas production and commodification of about 1.5 tons of organic fertilizer.

 Major equipment:
 Acid pool, regulation pool, physical and chemical filter, contact oxidation pond, corruption tower, sun road, dry room. Pig, gas, multi-functional household biogas manure technical background and significance of the construction. China's current agricultural production, mainly in the form of family as a unit, the majority of farmers also run both operating aquaculture farming, and household biogas digesters to farmers in the production and living waste as raw materials, fermentation, biogas and a variety of anaerobic Digestion products, so as to solve the farmers can live with, and meet certain requirements in production, so the construction of household biogas digesters in China has good prospects for development. This technology aims to design a practical, easy to manage the feeding, gas, fertilizer and the corresponding supporting multi-functional biogas technology.