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Recent years, with the development of production and increase in human consumption, in addition to not waste make timely and effective treatment, leading to all kinds of pollution in the world growing organic pollution problem which is becoming increasingly prominent. Waste emissions increasing relative increasing depletion of global fossil energy. Anaerobic fermentation of organic waste, biomass, and the fermentation product utilization, while alleviating the organic waste pollution and energy pressure. Anaerobic dry fermentation has to save water, save time managing working hours, the high rate of gas production, the pool capacity utilization high, saving the cost of waste disposal and other advantages, to achieve environmental protection and energy combination of solid organic waste processing. In this paper, the use of the pig farm pig manure anaerobic dry fermentation biogas technology research, and process handling pig farm pig manure benefit analysis to draw dry fermentation anaerobic treatment of pig manure is feasible recommendations. Pig manure anaerobic dry fermentation process research investigated retting time dung grass than vaccination rates and fermentation time (TS) four factors of pig manure and straw anaerobic dry fermentation biogas integrated indicators. Preferred orthogonal experiment through the process of the 4 factors and 5 levels, derived the optimal combination of process parameters. Of retting time set 2d, 3d, 4d, 5d, 6d five levels of fecal grass than setting 8:2,7:3,6:4,5:5,4:6 five levels, the vaccination rate set 10 %, 15%, 20%, 25%, 30% and five levels, fermentation time setting 10d, 15d, 20d, 25d, 30d five levels. Optimal process: fecal grass than 5:5 retting time 3d, the vaccination rate of 30%, fermentation days 30d. Amplification test on the basis of the optimal process 10 times, in order to observe the process route is stable, and its gas production characteristics in the case of the scale. Magnified 10 times trials the optimal process conducted in accordance with the process preferred test anaerobic dry fermentation to about 20 ~ 22d kg feed Nissan quantity of methane is the highest, up to 1600 ml · Kg -1 · d -1 . The whole process, the average kg material Nissan the methane amount 1157.5ml Kg -1 · d -1 . Methane content in the biogas in more than 45% of the time, 24d, 80% of the total anaerobic dry fermentation time; Nissan methane amount in more than 90% of the number of days on the average amount of Methane for 20d, 66.7% of the total anaerobic dry fermentation time . The best process tests the processing of pig manure and straw-effectiveness analysis found that the annual slaughter 10,000 hog pig farms, anaerobic dry fermentation engineering investment in fixed assets of approximately 400 million, the payback period 11.6 a project internal rate of return of 4.5%, but the investment risk is small; achieve 259.8t / a the BOD 5 removal 266.1t / a the COD removal produce biogas fertilizer 5235.4t / a, significantly reduce the odor, reduce 40t / a CH 4 emissions; 2880 people · d / a of can create jobs and help to promote farming enterprises with neighboring residents build harmonious relationship. Poor economic efficiency of the process, but better environmental and social benefits, starting from the point of view of the protection of the environment and sustainable development, is still worth to promote the use of suitable farm.
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