猪场废水厌氧消化液好氧处理过程酸化改进及菌群结构变化

摘要

When digested swine wastewater was directly treated with a sequencing batch reactor (SBR) process,the efficiency for COD and NH4+-N removal was low.Two methods were adopted in this study to improve the treatment process of digested swine wastewater,i.e.inoculating with anaerobic ammonia oxidation sludge (AN group) for the SBR system,and adding raw swine wastewater (RW group) to the treating wastewater.High throughput sequencing technology of Miseq was employed to analyze the variation of microbial community.The results showed that,comparing with that without taking improvement method(CG group),the AN group and RW group increased COD removal by 60.2％ and 102.6％,and increased total inorganic nitrogen (TIN) removal by 11.1％ and 73.3％,respectively.The improvement of RW group was the most obvious.The relative abundance of the Nitrosomonas of CG group(7.9％)and AN group(4.2％)were higer than RW group (0.79％).And the relative abundance of enriched ammonia oxidizing bacteria(AOB)was lower than that of nitrite oxidizing bacteria(NOB) in RW group.The enrichment of anaerobic ammonia oxidation bacteria (Anammox) only appeared in the AN group,but the relative abundance was low(Candidatus_Brocadia =0.05％).These could explain the NO2-N accumulation in CG group and AN group,but little accumulation in RW group.The relative abundance of Anammox was lower than the demand of high-efficiency autotrophic denitrification.%采用序批式反应器(SBR)工艺直接处理猪场废水厌氧消化液,处理系统发生酸化,对COD和NH4+-N去除效率较低.针对这一问题,文章试验了两种改进方案,分别是接种厌氧氨氧化污泥(AN)和厌氧消化液中添加猪场废水原水(RW).考察了不同改进方法对污染物的去除效果,并使用Miseq高通量测序技术分析了污泥中微生物多样性的变化情况.研究结果表明:与SBR直接处理猪场废水厌氧消化液相比,AN和RW组对COD去除率分别提高60.2％和102.6％,总无机氮(TIN)去除率分别提高了11.1％和73.3％,RW组的改进效果最明显.3个反应器中主要氨氧化细菌(AOB)是亚硝化单胞菌(Nitrosomonas),其对照(CG)组(7.9％)和AN组(4.2％)的相对丰度高于RW组(0.79％);RW组富集的氨氧化菌(AOB)相对丰度小于亚硝酸盐氧化菌(NOB);这些可解释CG组和AN组出现亚硝酸积累,而RW组没有出现亚硝酸盐积累.只有AN组出现厌氧氨氧化细菌的富集但相对丰度比较低(Candidatus_Brocadia=0.05％).AN组厌氧氨氧化菌相对丰度低于高效的自养脱氮的需求.