【作者】 张增胜；

【导师】 陈季华； 刘振鸿；

【作者基本信息】 东华大学 ， 环境科学与工程， 2010， 博士

【摘要】 农村分散式生活污水的随意排放对农村的生态环境构成了严重威胁,因地制宜的研究开发适合农村分散式生活污水处理的新技术与新工艺是解决农村水污染问题的关键所在。本研究基于上海市科委2007年度“科技创新行动计划”项目崇明生态岛建设科技专项“农村分散式污水处理适用技术的应用与示范”(编号：07dz12408),在崇明生态岛面源污染控制示范区国家级生态村-前卫村内调查了农村分散式污水的水质水量特征,建立了复合型生物净化槽-强化生态浮床组合工艺处理设施及相应微生物研究的小试装置,研究了复合型生物净化槽的启动过程及其对农村分散式污水中污染物质的去除效果和机理,比较了强化生态浮床与普通浮床对污染物质的去除效果、提出了强化生态浮床的强化依据及其对污染物质的去除效果和机理,然后对复合型生物净化槽优势菌株进行了条件优化性能测定及鉴定,对强化生态浮床系统微生物生态学特征与功能进行了分析研究,最后对组合工艺的总处理效果及其经济技术适用性作了相关的分析。崇明岛农村地区人均用水量约为95L/d,收集量只有用水量的40-45%,可收集的人均生活污水量约为40L/d。复合型生物净化槽-强化生态浮床组合工艺位于崇明岛前卫村,整个工艺依次包括化粪池、复合型生物净化槽和强化生态浮床。采用了好氧活性污泥预挂膜的方式对复合型生物净化槽进行微生物膜的培养与驯化,在流量为0.5m3/d、平均水温为25.7℃的条件下约10d便可培养成功。复合型生物净化槽对COD的去除效果明显,平均去除率夏季69.29%、秋季60.22%、冬季45.82%、春季59.45%,从沿程变化规律来看,第一格净化槽去除贡献率最大,整体上呈现出第一格、第二格及第三格净化槽去除贡献率的比值为5：3：2的趋势；复合型生物净化槽对氮的去除率不理想,但由于进水中氮的浓度较高,在低去除率的情况下仍旧保持了较高的氮去除量,第二格净化槽去除贡献率最大,整体上呈现出去除贡献率的比值为3：5：2的趋势；复合型生物净化槽对磷的去除效果较好,平均去除率夏季37.74%、秋季33.58%、冬季28.95%、春季32.36%,第一格、第二格净化槽去除贡献率较大,整体上呈现出去除贡献率的比值为4：4：2的趋势。在强化生态浮床中种植不同的浮床植物来实现全年不同季节植物的衔接作用,并在水生植物间利用纤维填料附着微生物膜,强化植物与微生物之间的协同作用,提高了微生物的浓度和数量,其对污染物质的去除效率明显优于普通浮床。第一阶段以茭白为浮床植物,对COD、NH4+-N、TP及SS平均去除率,普通浮床的分别为37.33%、74.54%、45.95%和50.99%,而强化生态浮床的分别为51.11%、79.32%、64.14%和82.15%；为实现全年不同季节上植物的衔接作用,第二阶段低温下选择喜寒植物水芹菜及第三阶段中温下选择喜暖植物睡莲作为浮床植物,结果表明强化生态浮床对污染物质均保持着较好的去除效果。对污染物质在强化生态浮床内沿程变化的研究表明污染物变化规律各有差异,COD、TN、NH4+-N及TP的浓度沿程逐渐降低的,COD和TP第一段去除贡献率最高,TN第三段去除贡献率最高；NH4+-N则不同季节有所差别,对于寒季而言,第二段去除贡献率最高,暖季则是第一段和第二段的去除贡献率均较高；SS的浓度沿程变化为先降低、再增加、最后降低,第一段去除贡献率最大；NO3--N及NO2--N的浓度沿程变化为先增加后降低,其中NO3--N的第三段去除量最大,NO2--N的第四段去除量最大。通过以培养基为单位进行初筛和脱氮除磷实验的复筛,得到了三株优势菌株：编号A-1、B-5及C-2,并在各自的最佳条件下进行了优化性能测定表明各菌株单独脱氮除磷的效果均不理想。将三种菌株按照1：1：1的比例复合4d对TN的去除率达到了87.4%,7d对TP的去除率达到了57.9%,脱氮除磷效果明显；运用正交试验的方法确定了复合菌株的最佳环境条件并在该条件下进行了模拟农村分散式生活污水脱氮除磷的性能测定,结果为14d中TN去除率达到了97%,TP去除率为63%,去除效果理想。运用离子色谱法和营养液培养法综合分析菌株脱氮除磷后的产物组成,再采用革兰氏染色法对菌株进行初步判定,然后从基因的角度进行鉴定,建立了三种菌株的系统树,运用16S rDNA基因序列分析法分析了三种菌株的基因序列,对菌株的理化指标分析表明：菌株A-1的理化指标符合奇异变形杆菌的特征,菌株B-5的理化指标符合门多萨假单胞菌的特征,菌株C-2的理化指标符合枯草杆菌的特征。对16S rDNA基因序列进行对比分析,发现与奇异变形杆菌同源性达到99%,与门多萨假单胞菌同源性达到98%,与枯草杆菌同源性达到98%。在强化生态浮床中,纤维填料酶活性、细菌数量及微生物量基本上是从前到后沿程依次降低的,都是以夏季7月份最高,其它三个季节无明显差异规律。蛋白酶、脲酶和脱氢酶活性上层纤维填料低于下层的,磷酸酶活性则是上层高于下层的,上层的细菌总数和下层的没有明显差异规律,微生物碳、氮均呈现出上层明显低于下层的,微生物磷则是上层高于下层。从沿程各段变化来看,蛋白酶和脲酶活性的沿程各段变化与TN的去除贡献率负相关性较差；磷酸酶活性的沿程各段变化与TP去除贡献率、脱氢酶活性的沿程各段变化与COD的去除贡献率均正相关性显著；从整体上来看,各个季节蛋白酶、磷酸酶活性分别与TN、TP总去除率正相关性显著；脲酶、脱氢酶活性分别与TN、COD总去除率相关性较差。纤维填料上细菌的数量与污染物去除率之间没有显著相关性。因此无论是酶活性、细菌数量还是微生物量,都是强化生态浮床中不同季节的植物、纤维填料及微生物等各种因素联合作用的结果,直接将一种参数与不同季节沿程各阶段污染物去除贡献率及污染物总去除率之间建立线性关系似乎过于简单。总的来说CBPT-EEFR组合工艺对COD、TN、NH4+-N及TP具有较好的去除效果,全年平均去除率分别达到了79.59%、61.06%、72.14%和77.14%,出水NO3--N、NO2--N、PO43--P和SS浓度全年平均值分别为1.533mg/L、0.442mg/L、0.36mg/L和27.3mg/L,其中出水COD达到了城镇污水处理厂一级A标准的要求,TN及TP出水达到了城镇污水处理厂一级B标准的要求,NH4+-N及SS出水达到了城镇污水处理厂二级标准的要求。通过对CBPT-EEFR组合工艺进行经济技术适用性分析发现,组合工艺基本处于零运行费用的状态,且具有出水水质好、不易堵塞、管理维护方便等优点,符合现阶段农村的经济技术发展现状,是一种生态的适用的农村分散式污水处理技术,便于在农村地区普及推广。更多还原

【Abstract】 Random disposal of rural decentralized domestic sewage has seriously threatened rural environment. Development of new technologies which are suitable for local decentralized domestic sewage treatment is the key way out. Based on the Scientific and Technical Innovative Program "the Applicable Technology and Demonstration of Treatment for Rural Decentralized Sewage" in Chongming Ecological Island which supported by Science and Technology Commission of Shanghai Municipality in 2007 (Grant No.07dz 12408), the quantity and quality for rural decentralized sewage were investigated in Qianwei village and both the pilot-scale combined biological purification tank-enhanced ecological floating raft (CBPT-EEFR) and the lab-scale experimental facility about the microorganism were constructed. After the build-up of experimental facilities, following subjects were studied:start-up of combined biological purification tank (CBPT); the removal efficiencies and mechanism of pollutants from rural decentralized sewage in the CBPT; the contrast of removal efficiencies of pollutants between the enhanced ecological floating raft (EEFR) and general floating raft (GFR); the enhanced basis of EEFR; the removal efficiencies and mechanism of pollutants in the EEFR; the performance measurement of the preponderant strains in the CBPT at the optimized conditions and their identifications; the ecological characters and functions of microorganisms in the EEFR; the total treatment effects by CBPT-EEFR system and its applicability on economy and technology.The quantity per person in rural area of Chongming-Island basin was 95L/d. And about 40～45% sewage could be collected through pipe network system corresponding to 40L/d per person. The pilot-scale craftwork of CBPT-EEFR located at Qianwei Village in Chongming-Island. The process consisted of the septic tank, the combined biological purification tank and the enhanced ecological floating raft in series. The biomembrane in the CBPT were cultivated and domesticated by precoating treatment with aerobic activated sludge under 0.5m3/d flow rate and 25.7℃average water temperature. After about 10-day cultivation and domestication, biomembrane in the CBPT were hanged successfully. The removal effect of COD was obvious by the CBPT with removal rate 69.29% in summer,60.22% in autumn, 45.82% in winter and 59.45% in spring, respectively. From on-way distribution analysis, the first-stage purification tank’s removal contribution was high. And the ratio of removal contribution among the first-stage, the second-stage and the third-stage purification tank was 5:3:2 on the whole. The removal rate of TN was bad by the CBPT. But due to the high TN influent concentration, the removal volume of TN was kept high at low removal rate. The second-stage purification tank’s removal contribution was high. And the ratio of removal contribution among the first-stage, the second-stage and the third-stage purification tank was 3:5:2 on the whole. The removal effect of TP was good by the CBPT with removal rate 37.74% in summer, 33.58% in autumn,28.95% in winter and 32.36% in spring, respectively. Both the first-stage and the second-stage purification tank’s removal contribution were high. And the ratio of removal contribution among the first-stage, the second-stage and the third-stage purification tank was 4:4:2 on the whole.Firstly, through planting different hydrophytes in the EEFR, it could achieve to converge of hydrophytes in different seasons. Secondly, fiber padding was embedded among the hydrophytes for adhering biomembrane. Because of these, the synergy between hydrophytes and microorganisms was enhanced and the concentration and amount of microorganisms were increased. So the removal rates of pollutants by EEFR were better than GFR. Zizania caduciflora Hand was used as floating raft’s hydrophytes at the first experimental stage. The average removal rates of COD, NH4+-N, TP and SS were 37.33%,74.54%,45.95% and 50.99% in GFR, relatively, and 51.11%、79.32%、64.14% and 82.15% in EEFR, relatively. In order to satisfy converge of hydrophytes in different seasons, floating raft’s hydrophytes were chosen as Oenanthe javanica which was kryophilous at the second experimental stage in low temperature and Nymphaea tetragona Georgi which likes warm at the third experimental stage in moderate temperature. And as results shown, both of them kept good removal effect of pollutants. The on-way distribution analysis of pollutants in the EEFR showed that there were different characters at different pollutants. The concentration of COD, TN, NH4+-N and TP decreased along the raft. Regarding to COD and TP, the first-stage raft’s removal contribution were high, and the third-stage raft to TN. NH4+-N was discrepant in different seasons which the second-stage raft’s was high in winter and the first-stage and second-stage raft’s was high. The concentration of SS decreased firstly, and then increased, at last decreased. And the first-stage raft’s removal contribution was high. The concentration of N03--N and NO2--N increased firstly, and then decreased. And the third-stage raft’s removal contribution was high for N03--N, and the forth-stage for NO2--N.Water samples collected from CBPT was concentrated and separated after cultivated in broth bouillon and N/P obligate media. Three kinds of preponderant strains were sieved from the vessels. They were named as A-1, B-5 and C-2. After the performance measurement of the preponderant strains in the CBPT at the optimized conditions, the removal effects of TN and TP were bad for each strain individually. But with the compound proportion of 1:1:1 for the three strains, the removal rate of TN in 4d was 87.4% and TP in 7d 57.9% by the compound strains. The logarithmic test was carried out to optimize degradation conditions in logarithmic growth phase, and at the optimize conditions, the removal rate of TN and TP in 14d was 97% and 63%, relatively for the simulative rural decentralized sewage. By chromatography of ions and standard detecting method under the optimal biodegradation conditions, the preponderant strains were confirmed to be Proteus mirabilis, Pseudomonas Medocina, Bacillus subtilis by gene sequencing. From the analysis of 16S rDNA gene sequencing, the homologies of Proteus mirabilis were 99%,98% for Pseudomonas Medocina, and 98% for Bacillus subtilis.Enzyme activity, bacteria, and microbial biomass were monitored in the EEFR. The results showed that enzyme activity, bacteria, and microbial biomass decreased along with flow direction. The concentrations of these in July were more than other months. The proteinase activities, urease activities and dehydrogenase activities increased from the upper layer to the bottom layer, and this was opposite for phosphatase activities. The bacteria population was similar from the upper layer to the bottom layer. The microbial carbon and nitrogen were increased from the upper layer to the bottom layer, and this was opposite for microbial phosphorus. From on-way distribution analysis, the variations of proteinase activities and urease activities were irrelevant to the removal contribution of TN. The variations of phosphatase activities and dehydrogenase activities were relevant to the removal contribution of TP and COD. Taken as a whole, proteinase activities and phosphatase activities were relevant to the total removal rate of TN and TP, and urease activities and dehydrogenase activities were irrelevant to the total removal rate of TN and COD. That is to say, enzyme activity or bacteria or microbial biomass resulted from multifarious factors of the EEFR, such as the hydrophytes in different seasons, fiber padding and microorganisms. So it is too simple to select one parameter as index of organic matter or nitrogen of phosphorus removal of the EEFR.In summary, CBPT-EEFR system can effectively remove COD, TN, NH4+-N and TP from rural decentralized sewage with the average removal rate 79.59%,61.06%, 72.14% and 77.14%, relatively. The effluent concentration of NO3--N, NO2--N, PO43--P and SS were 1.533mg/L,0.442mg/L,0.36mg/L and 27.3mg/L, relatively. The effluent concentration of COD could get the Municipal Wastewater Treatment Plant 1 A Standard, TN and TP for the Municipal Wastewater Treatment Plant 1 B Standard, NH4+-N and SS for the Municipal Wastewater Treatment Plant 2 Standard. From the applicability on economy and technology of CBPT-EEFR system, the running cost was much lower. At the same time, CBPT-EEFR system exhibited the advantages of steady effluent, hard to be jammed, simple operation and as well as high viability. It also meets with the economic and technical situation of rural areas. So it is an ecological and applicable craftwork for rural decentralized sewage and has large potential in wide spreading in rural areas.更多还原