| Pig-breeding industry plays an important role in animal husbandry industry and whole agriculture economic of X county. With rapid development of pig-breeding industry, especially for intensive pig culture, the pollution of environment became more and more serious by a lot of feces and waste discharged, as people's environmental protection awareness increased. Discharge amount and equivalent load of feces and urine in a year, and present situation of intensive pig culture and pollution in X area, also a case of feces and waste water treatment on large scale pig farm which were investigated in this article. The results of investigation as follow:1,The pig-breeding industry of X county became more and more intensive in these year. From 2004 to 2006, average discharge amount of feces and urine in a year of X were 1864,3075.6 thousand tons respectively, and average discharge amount of CODcr,BOD5,NH3-N,TP,TN,TK in a year were 124.6,21.7,101.4,79.5,211.1,382.1 thousand tons respectively.From 2004 to 2006, average equivalent load of feces,CODcr,BOD5,NH3-N,TP,TN,TK in a year of X were 658.2,1.86,1.81,1.51,1.18,3.15,5.69 thousand tons respectively. The average equivalent load of feces was very higher than the max number 30 ton/hm2 in theory, so pig-breeding industry of X was dangerous to environment protection.2,The farms which pig population was more than 300, were only 4.3% of total amount of farms in X county, and mainly located in Shitan,Jiangshe,Yangjiaqiao,Paitou,Xiangshui,Baishi town. The feces discharged by large scale pig farm were sold and used by themselves as organic fertilizer, and the waste water treated by traditional anaerobic fermentation process.The investigation of pollution present situation of large scale farm showed that, the land around large scale farm became more and more eutrophic; the concentration of pollutants in waste water improved with the pig population increased in a farm, and also the traditional anaerobic fermentation process was enough to treat the waste water; concentration of SO2,NO2 in the air around the large scale farm was normal, and improved the concentration of PM10,NH3 in the air, also the discharge amount of NH3 improved with the pig population increased in a farm.3,Investigation the case of feces and waste water treatment on large scale farm showed that:firstly, the solid-liquid separators as a pretreatment was effect measure to decreased the concentration of pollutants; secondly, waste water treated with anaerobic fermentation process, not only decreased the concentration of pollutants in waste water, also produced biogas; lastly, treated the waste water tor the furtherly by SBR process that would match the discharged standard of GB18596-2001. Also the solid-liquid separators had great ecological and social benefits, and it was worth learning by X county.The solid-liquid separators and anaerobic fermentation process of the large scale farm was effect to decrease the pollutants, but the NH3-N. But the SBR process decreased the concentration of NH3-N in the waste water effectly.In a word, the pig-breeding industry of X had been regionalized, large-scale, and industrialized development. There were the treatments and measures of decreasing pig-breeding industry pollution:a. establishing the environment protection awareness of people; b. controlling the scale of pig-breeding industry and planning scientifically; c. improving breeding pig and feeding in a scientific way; d. deepening and popularized the mode of ecological culture; e. adopting advanced fermentation process and improving the technology of feces and waste water treatment; f. making biogas,biogas slurry and feces industrialization and commercialization; g. establishing the system of pollution monitor and increasing the law enforcement dynamics.
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