Research On The Utilization Benefits Of Rural Household Biogas Digester In The City Of Huixian

Developing biomass energy, changing the traditional pattern of energy consumption, improving energy structure, promoting agricultural cleaner production, and making peasants’life with convenient energy is an important task of rural construction. Biogas, as a source of biomass, which has the advantages of simple operation, easy holding, low cost, clean and improving the rural landscape, has got a rapid development in rural areas. As a typical agricultural city, Huixian city is rich in biomass resources, which set a good foundation for the development of biogas. Therefore, it is important to study the comprehensive utilization benefit of rural household biogas digester, which can optimize the structure of rural energy and improve living quality of farmers.With the research object of household biogas digester, this paper learned from agricultural sustainable development theory, the emergy analysis theory, renewable energy theory, combined of statistical data and survey data, used grey correlation analysis method, emergy analysis method and analytic hierarchy process method to analyze the utilization situation of biogas in the city of Huixian. The following are conclusions out of the research:(1) The development of rural household biogas digester has a good development trend in the city of Huixian. By the end of2010, Huixian city built52,159household biogas digesters.The factors that affect rural household biogas digester, from big to small, are numbers of technicians, the scale of rural households breeding, rural per capita net income, construction and operating cost, alternative energy prices and subsidy.(2) In the economic benefit, the revenue net present value, internal rate of return, the investment pay-back period of the household biogas project families is CNY6995.95,54.03%, which is superior to the peasants without subsidy. Then this paper uses the emergy analysis method to analysis the energy flow in the breeding and planting system, and makes a conclusion that the VCR of a biogas households in breeding subsystem, the planting industry subsystem, the whole system of agricultural are1.91:1,1.70:1,1.89:1, which are higher than the peasant without household biogas. (3) In the ecological environment benefit, this paper set up the index system and identifies weight with analytic hierarchy process method. Then it draws the conclusion that the ecological benefit numerical value is5.53, which is between "very big" and "bigger".(4) In the alternative energy efficiency, through the energy conversion between biogas energy and electricity, liquid gas, coal, firewood and straw energy, this paper draws the result that there is a certain difference for different energy sources. And the alternative energy efficiency of biogas energy with commercial energy is higher than non-commercial energy.(5) In the social efficiency, the utilization of biogas has a positive effect in improving farmers’ consciousness of science and technology, training technical personnel, changing the structure of rural energy, promoting the liberation of the rural labor force, optimizing the agriculture structure, promoting the process of green agriculture, improving rural landscape.(6) Based on the empirical analysis, the research draws the conclusions that:the construction of rural household biogas digesters has good economic benefit, ecological environment, energy alternative benefit and social benefit in the city of Huixian. And it is worth to continue promoting in appropriate areas. But the service system, the value of eco-environmental benefits and the residue of biogas slurry to be strengthened, which makes the following recommendations:tighten propaganda and improve the penetration of household biogas digester; strengthen training and expand technical personnel team; enhance research and development to optimize the digester performance; broaden the channels and improve the methane gas service system; strengthen management and improve the ecological environmental benefits; integration of resources and development potential of biogas residues.