【作者】 吴根义；

【导师】 杨仁斌； 许振成；

【作者基本信息】 湖南农业大学 ， 生态学， 2007， 博士

【摘要】 畜牧业已成为中国农村经济中最活跃增长点和主要支柱产业,畜牧排放的大量废物对周围环境造成严重污染,畜牧养殖废水中污染物进一步加剧了我国水资源短缺的矛盾,严重制约着可持续发展战略的实施。畜禽养殖废水处理中碳氢化合物去除技术已相对成熟,而对氮、磷处理仍缺乏理想方法。基于新发现的废水脱氮机理,寻求一条工艺可靠、运行稳定、成本相对低的畜禽废水脱氮处理工艺,不但对创新废水处理方法有重要理论意义,而且对解决我国水体污染有着重要的应用价值。本文基于氨氧化机理,探索用厌氧—亚硝化—厌氧氨氧化组合工艺处理养殖废水。通过构建一套养殖废水处理试验装置,利用模拟废水培养出厌氧氨氧化污泥,利用实际养殖废水进行驯化运行;着重对处理过程中亚硝化反应和厌氧氨氧化反应两个处理单元各影响因素、处理效能进行了研究,并对亚硝化和厌氧氨氧化处理单元的微生物种群和反应机理进行了较深入探索。得出如下研究成果:1、通过分析畜禽养殖废水处理的现状和发展要求,总结出了四套畜禽养殖废水处理工艺流程,并确定水解酸化—UASB厌氧反应—SBR亚硝代反应—UASB厌氧氨氧化反实验工艺流程。2、选择适合反应器和反应条件,在较短的时间内可以培养出厌氧氨氧化微生物为主体的污泥,启动成功的厌氧氨氧化反应器表现出较高的NO₂^--N和NH₄⁺-N去除率。试验条件下用人工模拟养殖废水,以养殖场废水处理厌氧污泥为种泥通过150天培养出成熟的厌氧氨氧化污泥;培养成熟的污泥在HRT为24h时处理NO₂^--N和N₄⁺-N浓度均为490mg/L的人工模拟养殖废水、去除率均达到85%以上。3、较低浓度有机物和溶解氧对厌氧氨氧化反应器影响不大,但有机物和溶解氧的存在导致反应器中反应类型增加,好氧氨氧化菌主要消除溶解氧的危害、反硝化反应主要消除有机物的危害,正是由于几个反应在同一反应器中同时存在要求进水NO₂^--N/NH₄⁺-N比值随进水中溶解氧和有机物浓度的变化而改变。试验条件下模拟废水中有机物浓度为180mg/L、溶解氧浓度0.5mg/L、TN浓度为980mg/L时要维持厌氧氨氧化最高TN去除率应保持进水NO₂^-N/NH₄⁺-N的比值为1.45左右为宜。4、影响亚硝化反应进行的主要因素是溶解氧、pH值、温度,溶解氧浓度是控制亚硝化进行程度的决定性因素。实验表明:曝气量在0.036-0.04m³/h（通过多次测定此时溶解氧浓度为0.3mg/L左右）、pH值为8、温度为34-36℃之间反应器处于较理想的亚硝化状念。在此状态下,进水NH₄⁺-N和NO₂^--N浓度均为490mg/L、HRT为24小时出水NH₄⁺-N浓度为35.7mg/L,除率为92.6%;出水NO₂^--N浓度为18.7mg/L,去除率为96.2%。5、保持适合的亚硝化反应条件,通过控制反应时间可以对亚硝化反应发生程度进行控制,使亚硝化反应出水达到厌氧氨氧化微生物要求的NO₂^--N/NH₄⁺-N比值。试验中亚硝化反应器进水有机物浓度180mg/L、溶解氧浓度为0.03mg/L亚硝化反应时间控制在34h,出水中NO₂^--N/NH₄⁺-N比值为1.45满足厌氧氨氧化反应的要求。6、厌氧氨氧化反应器对养殖废水TN去除效果较好,处理过程中对NO₂^--N的去除效果明显优于对NH₄⁺-N的去除效果。人工模拟养殖废水培养成熟的厌氧氨氧化污泥经过61天的驯化培养可对实际养殖废水进行处理,并达到稳定运行状态。达到稳定运行后NH₄⁺-N去除率为45.5%、NO₂^--N去除率为95.1%、TN去除率为62.6%。7、厌氧氨氧化反应微生物对环境条件的适应能力较差,进水中有害物质严重影响其生长和活性。厌氧氨氧化反应器处理实际养殖废水时TN、NH₄⁺-N去除率均出现较大幅度下降,与人工模拟废水相比NH₄⁺-N去除率下降47%左右,NO₂^--N去除率下降不明显,TN去除率下降31.8%。8、采用亚硝化—厌氧氨氧化组合工艺进行养殖废水脱氮处理时两个工艺过程水力停留时间对TN去除效率有较大影响,亚硝化反应水力停留时间决定厌氧氨氧化能否完全进行。组合工艺亚硝化最佳水力停留时间为34小时,厌氧氨氧化反应器最佳水力停留时间为19-20小时。9、存在一定溶解氧和有机物的养殖废水进行脱氮处理时反应器的选择必须满足进水在反应器中处于较完整的推流状态,这样可在反应器中形成满足不同微生物生长条件的反应区,在反应器中加装填料有利于生长缓慢微生物的富集,形成以某类反应为主的主反应区。试验中发现在加填料的UASB反应器底部进水区好氧氨氧化微生物菌群富集主要发生好氧氨氧化反应,进水区上部一定范围内反硝化微生物菌群富集主要进行反硝化反应,上部处于完全缺氧和无机状态厌氧氨氧化微生物菌群富集主要进行厌氧氨氧化反应。10、养殖废水脱氮处理中微生物种类繁多,且不同的反应区起主要作用的微生物菌群存在较大差别。通过对亚硝化反应器、厌氧氨氧化反应器各不同部位污泥进行电镜扫描发现亚硝化反应微生物菌群以丝状菌为主、球菌和短杆菌也有一定量的存在;好氧氨氧化反应微生物菌群以丝状菌为主,厌氧氨氧化反应微生物菌群以球菌和短杆菌为主。更多还原

【Abstract】 The livestock husbandry has become the most active growth point and the main pillar industry of rural economy in China. The environment was polluted gravely by a large amount of waste discharged by livestock and poultry, and the contamination of livestock wastewater has aggravated the shortage of water resource, The strategy of sustainable development was seriously restricted. The technology of eliminating hydrocarbon in livestock wastewater is already relatively mature, but still lack an ideal method to nitrogen and phosphorus. Based on the newly discovered mechanism of wastewater denitrification, seeking for a reliable ,stable and economical craft for denitrification of livestock wastewater not only has important theoretical significance for innovative wastewater treatment methods, but also has important applications value to solve the water pollution. Based on the ammonia oxidation mechanism, anaerobic - Nitrosation - ANAMMOX combination to treat .with waste water was researched in this text. Through construction of a suit of experimental treatment plant for Livestock Wastewater , ANAMMOX sludge was cultivated successfully by simulated wastewater and The plant was run by ANAMMOX sludge which domesticated by actual wastewater; the anaerobic-nitrosation-ANAMMOX combined processess for treating livestock wastewater has been researched, and the influencing factors, treatment efficacy and reaction mechanism of nitrosation and ANAMMOX processess were studied respectively, and the microbial community in nitrosation and ANAMMOX processess were analyzed.The main results were as follows:1、Situation and developmental requirements of Livestock wastewater treatment was analyzed and four sets of livestock and poultry wastewater treatment process was summarized. A Hydrolysis-UASB anaerobic reactor-SBR Nitrosation reaction-UASB ANAMMOX anti-experimental process was determined.2、Selecting the appropriate reactor and the reaction conditions can cultivate ANAMMOX microorganisms as the main sludge in a short period of time. ANAMMOX reactor showed high NO₂^--N and NH₄⁺-N removal rate in a successful state. when artificial livestock wastewater was simulated, The mature ANAMMOX sludge which seeded with anaerobic sludge treat of livestock wastewater was cultivated successfully in 150 days. When the influent concentration of NO₂^-N and NH₄⁺-N was 490mg/L, the both of removal rate was above 85% at HRT of 24 h.3、Low concentrations of organism and dissolved oxygen has little impact to ANAMMOX reactor, but the existence of organism and dissolved oxygen in the reaction could increase types of reaction in the reactor. Aerobic ammonia-oxidizing bacteria mainly to eliminate the harm caused by dissolved oxygen, Denitrification mainly to eliminate the harm caused by organism.Because sereval reaction exist in the same reactor,the ratio of NO₂^--N/ NH₄⁺-N must be adjusted as the amount of organism and DO in influent wastewater. Keeping the ratio of NO₂^--N/ NH₄⁺-N 1.45 is good for maintaining optimum TN removal rate of ANAMMOX with the concentration of organism 180mg/L, DO 0.5 mg/L and TN 980 mg/L in synthetic wastewater.4、Dissolved oxygen, pH, temperature are the major factors to affect Nitrosation reaction , whereas dissolved oxygen concentration is the crucial factor to control of the degree of denitrification.Data suggested that: The reactor cause to ideal nitrosation condition under the conditions of value of pH 8,aeration rat was from 0.036 m³/h to 0.04m³/h（DO was 0.3mg/L by repeated determine）, temperature was 34-36℃. When the influent concentration of NO₂^--N and NH₄⁺-N was 490mg/L, the concentration of NH₄⁺-N in effluent was 35.7mg/L and removal rate was 92.6% at HRT of 24 h, While the concentration of NO₂^--N in effluent was 18.7mg/L, the removal rate was 96.2%.5、Maintaining suitable reaction conditions of Nitrosation , it can controlling of the degree of denitrification by controlling the reaction time, so that the effluent reached requirements NO₂^--N/NH₄⁺-N ratio of anammox microbial.In the studies, nitrosation process with time of 34h, concentration of organism 180mg/L and DO of 0.03 mg/L in influent, ratio of NO₂^--N / NH₄⁺-N 1.45 are good for ANAMMOX reaction.6、ANAMMOX reactor has a outstanding treatment for TN. in the Livestock Wastewater. In the process,the removal rate of NO₂^--N is superior to NH₄⁺-N.During 61 clays domestication, the mature ANAMMOX bacteria treated with synthetic livestock wastewater could treat with actual livestock wastewater,and work stably. the removal rate of NH₄⁺-N , NO₂^--N and TN was 45.5%, 95.1% and 62.6%, respectively after stably working.7、ANAMMOX bacteria have inferior capacity to adapt to environmental conditions,so the harmful materials in actual livestock wastewater influenced the growth and activity considerably. The revomal rate of TN,ammonia and nitrite has descended significantly. Compared with the synthetic livestock wastewater , revomal rate of NH₄⁺-N declined 47%, NO₂^--N didn’t decline obviously,and TN declined 31.8%.8、The HRT in the Nitrosation- ANAMMOX combined processess have remarkably influence for the removal rate of TN when they were used to treat with nitrification in the Livestock Wastewate. HRT in the Nitrosation reaction decided whether ANAMMOX was completely progressed.Nitrosation- ANAMMOX combined processes have great effect on nitrogen removal of livestock wastewater,the nitrosation optimal water power standing time of the process was 34h, ANAMMOX reactor optimal water power standing time of the process was 19-20h.9、choosing reactor for the denitrification treatment in the Livestock Wastewater which exist a certain of dissolved oxygen must keep influent in push flow state.Then different growth conditions of microbial are reached and reaction zone is formed in the reactor.It is benefit for enrichment of slowly development microbial. The installation in the reactor is good for enrichment of slowly development microbial and it can form a certain reaction dominating the main reaction zone.In this studies, aerobic ammonia oxidation reaction occurred mainly in ammonia oxidation zone where aerobic microbial community enriched at the bottom of the in let zone of UASB reactor . denitrification reacted during the top of inlet zone and ANAMMOX reacted in the top of the reactor that lack oxygen and filled with inorganisms.10、There are varieties of microorganisms for denitrification treatment of Livestock wastewater, and there is a outstanding difference between microbial community which play a major role in different reactions.The scanning electronmicrograph showed that microorganism species in different parts of nitrosation and ANAMMOX reactors were different .the predominantly microorganism species was Filamentous bacteria,accompanied with Methanobacterium and Sarcina-type bacteria in nitrosation reactor, but Methanobacterium and Sarcina-type bacteria were predominantly in ANAMMOX reactor.更多还原