洛克沙胂对生物脱氮过程的干预及其行为研究

发布时间：2018-03-01 02:17

本文关键词： 生物脱氮洛克沙胂微生物毒性迁移和生物转化生物群落多样性　出处：《合肥工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：洛克沙胂(4-羟基-3-硝基苯砷酸)是一种被广泛用于畜禽养殖业的饲料添加剂,其很难在动物体内转化,会随动物的排泄进入环境。环境中的洛克沙肿容易在生物或非生物的作用下转化为毒性和迁移性更强的无机砷。最终洛克沙胂及其转化产物通过粪肥的施用进入土壤,通过废弃物的露天堆放由雨水的冲刷带入自然水体或通过下渗进入地下含水层引发潜在的环境风险。当洛克沙肿随动物粪便进入养殖废水时,很有可能对养殖废水的生物处理过程造成不利影响。本文从洛克沙胂和活性污泥微生物在废水处理过程中的交互作用出发,系统的研究了洛克沙肿对生物脱氮过程的干预及其行为。具体包括：洛克沙胂对生物脱氮过程的急性干预；洛克沙胂对生物脱氮系统的长期生态影响；洛克沙胂的长期胁迫对活性污泥微生物种群结构的影响。通过实验研究,本文取得几条重要结论并简述如下：(1)洛克沙胂及其生物转化产物对生物脱氮过程具有显著的不利影响,并且通过一段时间的驯化并不能使情况好转。与硝化阶段相比,反硝化阶段无机砷的生成导致微生物的反硝化作用被更强烈的抑制。(2)洛克沙胂在生物脱氮过程中很难被去除和生物转化,极少量的洛克沙胂转化为4-羟基-3-氨基苯砷酸(HAPA)和无机砷,这增加了微生物微生态环境中的无机砷含量。污泥絮体中无机砷的富集使微生物胞外聚合物和细胞内的无机砷水平升高,最终抑制了活性污泥微生物的呼吸作用和多种酶活性。(3)洛克沙胂的长期胁迫使活性污泥系统中的微生物多样性明显下降且改变了活性污泥微生物的群落结构。气单胞菌属和嗜甲基菌科的细菌逐渐取代了活性污泥中不动杆菌属细菌的优势地位,成为新的优势菌种。
[Abstract]:Roxarsone (4-hydroxy-3-nitrobenzene arsenic acid) is a feed additive widely used in livestock and poultry breeding, which is difficult to transform in animals. The roxarsone can enter the environment with the excretion of animals. The roxarsone in the environment is easily converted into inorganic arsenic, which is more toxic and migratory, under the action of biological or abiotic. Finally, roxarsone and its transformation products enter the soil through manure application. Potential environmental risks arise from the open-air piling of waste by Rain Water's scouring into natural waters or from infiltration into underground aquifers. When Locke's sand swells into the aquiculture wastewater with animal droppings, In this paper, the interaction between roxarsone and activated sludge microorganisms in the process of wastewater treatment is discussed. The intervention and behavior of roxarsone on biological denitrification process were systematically studied, including the acute intervention of roxarsone on biological denitrification process, the long-term ecological effect of roxarsone on biological denitrification system, and the effect of roxarsone on biological denitrification. The effects of roxarsone on the microbial population structure of activated sludge were studied. Several important conclusions were obtained and summarized as follows: 1) roxarsone and its biotransformation products had significant adverse effects on the biological denitrification process. And after a period of acclimation, things don't get better. Compared with the nitrification stage, The formation of inorganic arsenic in denitrification stage results in stronger inhibition of microbial denitrification.) roxarsone is difficult to be removed and biotransformed during biological denitrification. A very small amount of roxarsone was converted to 4-hydroxy-3-aminobenzene arsenate (HAPA) and inorganic arsenic. The concentration of inorganic arsenic in sludge floc increased the levels of inorganic arsenic in the extracellular polymers of microorganism and in the cells. The microbial diversity in activated sludge system was significantly decreased and the community structure of activated sludge microorganism was changed under the long-term stress of roxarsone. Acinetobacter bacteria in activated sludge were gradually replaced by bacteria belonging to the genus Monomonas and methanophilic bacteria. To become a new dominant strain.
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X713

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