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The large-scale livestock and poultry brings a lot of dung, not only causing the pollution of the surrounding environment, but also causing the spread of the disease. Fermented dung is a good way. The ambient temperature is low, so that the digesters internal fermentation temperature is low, affecting the biogas generated. Also in the farms heating and cooling systems consume large amounts of electricity. In this paper, a new energy system is formed with a ground source heat pumps, biogas digesters, and the breeding shed. According to the system design, simulation and calculation, obtain the following results:1. According to the present, the proportion of the scale of farming in Henan Province, choose breeding stock2000pig farms for the object, and then calculate the area of the farm, pig dung emissions, the size of digesters, and establish their quantitative relationship.2. Calculated by numerical simulation in different fermentation temperature and ambient temperature conditions and the different thickness of the insulation layer and the insulation layer, obtain the temperature distribution of the digester and the surrounding soil and digester heat dissipation.3. By a numerical simulation for digester heated wall installation coil,simulation results show that:the digester is larger and the centre of the digesters is the lower temperature, therefore it is needed to increase the turbulence of these regionsextent, making the digester temperature distribution more uniform.4. Forming a new system with breeding shed, digester and a ground source heat pump during the cold season and hot season, the system needs that heat and cold is basic balance, therefore GSHP systems extract heat from the soil and cold basically the same, which can guarantee the efficient and stable operation of the heat pump system. 5. Analysis of the initial investment and running costs of the heating and cooling mode of the farms and ground source heat pump system, we get the ground source heat pump is more economic, energy, and development prospects.
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