Two Large-Scale Farm Manure Disposal Systems’ Environmental Impact Assessment Of Life Cycle

With the rapid development of China’s large-scale intensive aquaculture, Livestock manure has being an important pollution of environment. Farm waste pollution to the environment is mainly manifested in the water pollution, air pollution, the spread of disease and soil pollution, etc Evety region of our country has taken harmless, reduction and recycling technologies for processing actively. However, it will inevitably have a negative impact on the environment during the process of livestock and poultry control. So, it is necessary to carry out the envitonmental impact study of large-scale farm manure handing system including treatment process and the product obtained after treatment.This paper builds a life cycle assessenmt model of the large-scale farm manure handing system based on the life cycle theory. Then the writer takes the large-scale cattle farm for example, using life cycle assessment model to compare aerobic composting and anaerobic fermentation; Using the evaluation result of LCA, this paper uses the fuzzy comprehensive evaluation method based on membership to get the pros and cons by comparing aerobic composting and anaerobic fermentation considered the economy, environment and social factors. This paper evaluated the products of the two types of treatment using the LCA model. It discussed the feasibility of the application of organic fertilizer instead of chemical fertilizer based on the result.The results showed that:(1) The anaerobic fermentation’s environmental impacts is better than aerobic composting process, the aggregate life cycle environmental impact index were respectively0.0155and0.0178. In terms of the manure treatment process,the anaerobic fermentation process is more friendly to environmentally.(2) Considering the four factors comprehensively, the overall evaluation results of anaerobic fermentation process, aerobic composting process and untreated process were92.53,87.30,64.49, anaerobic fermentation process was the highest scores, which showed that anaerobic fermentation process was the best suited treatment approach for scaled cattle farms.(3) The environmental impact of anaerobic fermentation product is better than aerobic compost product, the aggregate life cycle environmental impact index of product of anaerobic fermentation and product of aerobic compost were respectively0.0177and0.0219.In terms of the manure treatment products,the anaerobic fermentation products is more friendly to environmentally.(4) Life cycle assessment methodology is used to establish inventory of resource use and emission and to comparative assessment of the life cycle environmental impacts of urea and organic fertilizer. The results showed that for the whole life cycle resource depletion, global warming potential, acidification potential value of the environment and eutrophication potential value of organic fertilizer were all lower than fertilizer. The aggregate life cycle environmental impact index of fertilizer is1.17201in comparison with0.4268for organic fertilizer. If insteaded, will reduce energy consumption59.22GJ, global warming, acidification and eutrophication potential will be reduced by36.99%,62.96%,61.54%each.Thus, the environment impact load for organic fertilizer is lower, and organic fertilizer have the potential to displace fertilizer taking the energy and environmental aspects into consideration.