江西省规模化养殖场调查及沼液理化性质研究

Investigation of Large-scale Farms and Research on Physical and Chemical Characteristics of Digested Slurry in Jiangxi Province

针对规模化养殖场粪污处理等一系列农村环境污染问题,以江西省8家规模化养殖场及场内沼气工程为研究对象,获取各养殖场及沼气工程的基本信息,并对养殖场内大气环境进行了监测。同时,采集进料池、发酵罐和沼液池料液样品,对所采集料液的理化特性进行检测和分析。结果表明:沼气工程设计施工规范,配套设施较齐全,主要以畜禽粪便为原料,但进料料液总固体(TS)<3%,以低浓度发酵为主。发酵温度以中温发酵为主,由于冬季气温偏低,难以达到中温发酵标准(25~40℃)。沼气利用方式单一,且沼气产量存在季节差异,夏季沼气产量高,冬季产气量低。沼液、沼渣综合利用配套不足,且利用方式不规范。养殖场恶臭污染物浓度下风向高于上风向,冬季高于夏季,夏季和冬季NH_3和H_2S浓度日均值分别为0.078和0.011 mg/m^3,0.104和0.016 mg/m^3,均低于国家规定的限值。自进料池到沼液池料液pH处于7.2~7.4,呈中至微碱性,经厌氧发酵后沼液中NH_4^-N、总氮(TN)和化学需氧量(COD)含量分别>400、>800和>1 400 mg/L,养分含量仍然非常高。该调查结果可为规模化养殖场及沼气工程的健康运行与发展提供参考。

Aiming at a series of rural environmental pollution problems of the fecal pollution treatment in large-scale farms,taking 8 large-scale farms and field biogas projects in Jiangxi Province as research object,the basic information of farms and biogas projects were obtained,and the atmospheric environment in the farms was monitored.Meanwhile,samples of feed pool,fermenting tank and biogas liquid pool were collected,and the physical and chemical properties of the collected material were detected and analyzed.The results showed that:biogas engineering design and construction specifications and facilities were relatively complete,mainly using livestock and poultry manure as raw materials,but the feed material TS<3%,with low concentration fermentation.The fermentation temperature was mainly medium temperature fermentation.Because of the low temperature in winter,it was difficult to reach the medium temperature fermentation standard(25-40℃).The biogas utilization method is single,and there is seasonal difference in biogas production,the biogas production in summer is high,and the gas production in winter is low.The comprehensive utilization of biogas slurry and biogas residue inadequate facilities,and the way of use is not standard.Under the concentration of odor pollutants,the wind direction is higher than the upper wind direction,and winter is higher than that of summer.The daily average values of NH 3 and H 2S concentrations in summer and winter were 0.078 and 0.011 mg/m 3,0.104 and 0.016 mg/m 3,respectively,which were all lower than those specified by the state.The pH value of the feed liquid from the feed pool to the biogas slurry tank is between 7.2-7.4,showing neutral and weak alkaline.After anaerobic fermentation,the contents of NH 4-N,TN and COD in biogas slurry are>400,>800 and>1 400 mg/L,respectively,the nutrient content is still very high.The results can provide a reference for the healthy operation and development of large-scale farms and biogas engineering.