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类型 应用研究 预答辩日期 2018-03-04
开始(开题)日期 2011-04-01 论文结束日期 2015-08-21
地点 热能所一楼会议室 论文选题来源 中央、国家各部门项目     论文字数 8.2 (万字)
题目 生物生态组合型农村生活污水处理系统污染物去除特性及工艺模拟研究
主题词 农村生活污水,大深径比厌氧器,跌水充氧,水生蔬菜型人工湿地,工艺模拟
摘要 随着我国农村社会与经济的发展、农村居民生活与生产方式的转变,农村水环境质量持续恶化。调查表明农村生活污水是水环境的主要污染源之一,对水资源安全构成潜在威胁,制约了农村地区社会、经济的持续发展。高效、低耗与可持续的农村生活污水治理技术研究已成为国内水污染控制领域的重要研究方向之一。 针对农村水污染特征和我国农村现状,以农村生活污水处理过程中的节能减排和资源化利用为出发点,本课题组开发了由大深径比厌氧反应器、缺氧除臭反应器、跌水充氧反应器和人工湿地组成的生物生态组合型污水处理系统。组合系统既具有厌氧-缺氧-好氧生物处理工艺污染物降解的高效性,也具有人工湿地生态处理工艺管理维护的简便性。本文对组合系统处理农村生活污水的污染物去除效能进行了深入研究,具体开展:不同水温大深径比厌氧反应器的工艺优化及运行特性分析;缺氧段脱氮除臭过程优化;跌水充氧段污染物去除效率及生物膜特性研究;水生蔬菜型人工湿地氮磷资源化利用、污染物去除途径研究与运行方式优化。基于上述研究,建立组合系统工艺模型,并进行验证。主要研究成果简述如下。 启动大深径比厌氧反应器,考察了水温、水力停留时间对厌氧反应器有机物去除率、产气量、出水臭阈值等的影响。反应器产气率与水温成正比;水力停留时间与有机物去除率呈显著正相关关系,且随着水力停留时间的延长,产气量减少,出水臭阈值降低。水温为15℃~25℃时,经济水力停留时间为72h,有机物去除率可达79.7%;水温为8℃~15℃时,经济水力停留时间为144h,有机物去除率为66.5%。对于高碳浓度的污水,可通过厌氧发酵将有机物转化为沼气,在去除有机物的同时,实现对有机物的资源化利用;对于低碳浓度的污水,则应首先考虑有机物的去除。 缺氧除臭反应器内悬挂弹性填料,考察了不同水温下,回流比和水力停留时间对缺氧段脱氮除臭性能的影响。随着回流比增加,缺氧段出水的总氮、硫化氢、挥发性脂肪酸(Volatile fatty acid,VFA)和臭阈值均有显著下降。水温为15℃~25℃时,调节回流比至200%,可获得较高的总氮、硫化氢、VFA和臭阈值的去除率,分别为52.3%、82.6%、83.6%和83.0%;水温为8℃~16℃时,需增加回流比至400%才能有效去除臭味,总氮、硫化氢、VFA和臭阈值的去除率分别为30.1%、64.1%、72.2%和60.0%。 优化设计了跌水充氧装置,较优构形为:设五级跌水充氧池,池内水深0.4m,填充无纺布;使用具有水平间距为5cm竖缝的跌水挡板,一、二级跌水充氧池各设两级跌水挡板,垂直间距25cm,其它充氧池各安装一级跌水挡板。使用改进后的跌水充氧接触氧化装置,当水力停留时间为2h时,COD及NH4+-N的去除率分别达到51.4%和54.1%。试验水质条件下,COD与NH4+-N容积负荷分别小于1.5 kgCOD/(m3?d)、0.2 kgNH4+-N/(m3?d)时,可获得较优污染物处理效果。 水生蔬菜人工湿地的适宜水力负荷为0.2m3/(m2?d),栽培水深为10cm,此时TN去除负荷达到最大值1.87g/(m2?d);采用收割1/4蔬菜量的收割法,可保证营养盐的有效去除及较高的蔬菜产量。分析了水生蔬菜人工湿地内氮磷去除途径,空心菜的吸收作用和微生物降解是TN去除的主要途径,去除贡献率分别在47.68~59.57%和39.43~51.34%之间;TP的去除途径主要是空心菜的吸收,贡献率在58.4~77.5%之间,植物对磷素去除的贡献率远高于普通潜流式人工湿地内植物吸收对磷素去除的贡献率。 潜流人工湿地内,以煤渣为基质的湿地虽然在低水力负荷(即0.1m3/(m2?d))时去除率相对较低,但随着负荷增加至0.2m3/(m2?d),去除率仍稳定在50%左右,其对负荷变化有较强的抗冲击能力;而采用碎砖、砾石、细砂构建的组合基质湿地仅在低水力负荷时对污染物有明显的去除,水力负荷从0.1m3/(m2?d)提高至0.2m3/(m2?d),去除率从70.2%逐渐降低至50.9%。 串联水生蔬菜人工湿地和潜流人工湿地,考察了串联顺序和水力负荷对尾水中污染物去除的影响。水生蔬菜湿地前置时,水力负荷为0.3m3/(m2?d)时,污染物去除负荷较大,COD、TN、TP分别达到8.41 g/(m2?d)、2.6 g/(m2?d)和0.18 g/(m2?d),出水可达到一级A标准;潜流湿地前置时,较优水力负荷仍为0.3m3/(m2?d),此时COD、TN、TP去除负荷分别为7.37m3/(m2?d)、1.96 m3/(m2?d)和0.14 m3/(m2?d),出水仅可达到一级B标准。因此应用中建议采用前置水生蔬菜人工湿地、后置潜流湿地的模式,以保证出水稳定达标。 分析了不同组合的湿地系统内的蔬菜(空心菜和水芹菜)的食用安全性,蔬菜内农药残留和重金属均未超出《茄果类蔬菜等55类无公害农产品检测目录》(农办质〔2013〕17号文件)和《食品中污染物限量》(GB 2762-2012)的规定。因此,采用水生蔬菜人工湿地处理经过生物处理后的农村生活污水尾水,可实现污水中氮磷资源化利用,构建污染净化型农业,实现污水治理和农业生产的有机结合。 基于物料守恒,建立了农村生活污水生物生态组合处理系统中各单元的污染物去除模型,并进行了全流程的耦合。工艺模型对污染物去除的模拟结果与实测值之间的偏差维持在5%~25%。各单元模型以及全流程耦合模型可用于预测组合系统的运行效果与指导运行工况调整。 本文研究结果表明,“厌氧-缺氧-跌水充氧-人工湿地”组合系统可有效处理农村生活污水,并实现污水中有机物、氮和磷的资源化利用,对构建高效、低耗、可持续的农村污水处理体系、改善农村水环境质量具有重要的指导意义。
英文题目 Study on the Pollutant Removal Characteristics and Process Simulation of the Rural Domestic Sewage in Biological-Ecological Treatment System
英文主题词 rural domestic sewage, large depth-diameter ratio anaerobic reactors, dripping aeration reactors, aquatic vegetables type artificial wetland, process simulation
英文摘要 The water quality in China’s rural areas is continually deteriorating, with the social and economic development and the transformation of life and production mode. It is showed in survey that rural sewage is one of the main sources of water environment, a potential threat to water resources security, restricting the sustainable development of the rural society and economy. Thus, the sustainable rural sewage treatment technology research with high efficiency, low consumption has become one of the important research directions in the field of water pollution control. According to the rural water pollution characteristics and the current situation of the rural areas, in the aim of energy conservation, emissions reduction and resource utilization, a new process of rural sewage treatment was developed combined with large depth-diameter ratio anaerobic reactors, anoxic reactors, dripping aeration reactors and artificial wetland, which is called biological and ecological wastewater treatment system. The combined system is highly efficient to remove pollutions as anaerobic-anoxic-aerobic biological treatment technology, and also easy to manage and maintain as artificial wetland ecological process. In this thesis, the pollution removal efficiency of the combined system was studied, in the aspects as followed: 1.The process optimization and operation characteristics analysis on different temperature of large depth-diameter ratio anaerobic reactors; 2.The process optimization of denitrification deodorization in anoxic reactors; 3. The pollution removal efficiency and biological membrane characteristics analysis in dripping aeration reactors; 4.The research on nitrogen and phosphorus resource utilization and pollution removal mechanism and the operation mode optimization in the aquatic vegetables type artificial wetland. Based on the research above, a combined system process model is also established, and verified in practical treatment. The main research results are briefly as follows: 1. The effects of temperature and hydraulic retention time (HRT) on organic pollution removal efficiency, gas production and effluent odor threshold were researched in the large depth-diameter ratio anaerobic reactor. The gas production rate is proportional to the temperature; HRT and organic matter removal rate have significantly positive correlation, and with the extension of HRT, the gas production rate decreased, odor threshold also lowered. When the water temperature was 15℃~25℃, the economic HRT was 72 h, organics removal efficiency reached 79.7%; When the temperature was 8℃~15℃, the economic HRT was 144 h, organics removal efficiency reached 66.5%. As for the sewage with high carbon concentration, organic matter can be converted to biogas by anaerobic fermentation, simultaneously realizing the recycling use of organic matter; as for sewage with low carbon concentration, the removal of organic matter should be first priority. 2. The effects of temperature, reflux ratio and HRT on denitrification deodorization were researched in the anoxic regulation reactor hung with elastic filler. With the increase of reflux ratio, the value of total nitrogen, hydrogen sulfide, Volatile fatty acid (Volatile fatty acid, VFA) and odor threshold which was in the anoxic period has dropped significantly. When the water temperature was 15℃~25℃, the reflux ratio was regulated to 200%, the removal rate of total nitrogen, hydrogen sulfide, VFA and threshold value can be obtained as 52.3%, 82.6%, 83.6% and 82.6% respectively; When temperature was 8℃~15℃, the reflux ratio was required to increase to 400% in order to effectively remove odor, the removal rate of total nitrogen, hydrogen sulfide, VFA and odor threshold can be obtained as 30.1%, 64.1%, 72.2% and 64.1% respectively. 3. The design of the dripping aeration devices was optimized: an aerobic reactor with five steps plunge pool which each step was 0.4m depth were set up, filled with non-woven fabric; a dripping baffle with horizontal spacing of 5cm was used, and the first and secondary reactor was devised with two baffles each, with the vertical interval of 25cm, and other reactors with one baffle. With the improved baffles, when the HRT was 2h, the removal rate of COD, NH4+-N reached 51.4% and 54.1% respectively. Under the test condition, when COD and NH4+-N volume load was less than 1.5 kgCOD/(m3?d), 0.2 kgNH4+-N/(m3?d) respectively, the reactor have reached to a better treatment effect in system. 4. The most suitable hydraulic load for the aquatic vegetables type artificial wetland is 0.2 m3/(m2?d), with the planting depth of 10 cm, and the TN removal load can reach maximum of 1.87 g/(m2?d); Using the harvest method of 1/4 vegetable, the effective nutrient removal and higher vegetable production can be ensured. The nitrogen phosphorus removal pathways in aquatic vegetables type constructed wetland were analyzed. The absorption of water spinach and microbial degradation are the main ways of TN removal, the rates of which were between 47.68~59.57% and 39.43~51.34%; The absorption of water spinach is the main approach of TP removal, the rates of which were between 58.4~77.5%. The contribution of plants in the aquatic vegetables type artificial wetland to remove phosphorus is much higher than those in normal artificial wetland. 5. In the Subsurface flow constructed wetland(SFCW), the wetland with cinder as substrate had although a low removal rate under a low hydraulic load (i.e. 0.1 m3/(m2?d)), but as the hydraulic load increased to 0.2 m3/(m2?d), the removal rate remained stable around 50%, which showed its stronger ability to resist shock; However, the wetland with rubble, gravel, fine sand as substrate had obvious removal of the pollutants only at low hydraulic load, and when hydraulic load increased from 0.1 m3/(m2?d) to 0.2 m3/(m2?d), the removal rate was gradually reduced from 70.2% to 50.9%. 6. The aquatic vegetables type artificial wetland and SFCW were combined to examine the influence of the tandem sequence and the hydraulic load to tail water pollutants removal. When the aquatic vegetable type artificial wetland was in the former, and the hydraulic load was 0.3 m3/(m2?d), the pollutant removal load is higher, e.g. COD, TN, TP, respectively was 8.41 g/(m2?d) and 2.6 g/(m2?d) and 0.18 g/(m2?d), having reached Standard A of the first class; When the SFCW was in the former, the optimum hydraulic load is 0.3 m3/(m2?d), the COD, TN and TP removal load respectively was 7.37m3/(m2?d), 1.96m3/(m2?d) and 0.14m3/(m2?d), having barely reached Standard B of the first class. It is recommended that SFCW is placed at the rear, in order to guarantee the stable effluent standard. 7. The food security, agricultural vegetable pesticide residues and heavy metals of vegetables (water spinach and water celery) in the different combination wetland system were analyzed, according to "Monitoring directory of 55 Pollution-free agricultural products" (The Ministry of Agriculture 17th file in 2013) and "the Contamination Limitations in Food" (GB 2762-2012), which were not beyond the regulations. Therefore, the utilization of aquatic vegetable type artificial wetland after biological treatment can realize nitrogen and phosphorus resource recycle, build pollution purification type agriculture, combine sewage disposal with agricultural production. 8. Rural domestic sewage pollution removal models with biological-ecological treatment system were built based on material conservation, and the models were also coupled. The results of process model on pollutants removal of simulation were similar with the practical measured values, with the deviation maintained at 5%~25%. Each element model and coupling model can be used to predict combination system of whole flow operation effect and operation condition adjustment. In this thesis, the research results showed that “anaerobic-anoxic-dripping aerobic-artificial wetland” combination system can be used to effectively treat the rural domestic sewage, and realize the organic matter, nitrogen and phosphorus recycling use in sewage, in order to construct a sustainable rural sewage treatment system with high efficiency and low consumption, improving the rural water environment quality.
学术讨论
主办单位时间地点报告人报告主题
能源与环境学院 2013.10.21 五五楼会议室 张跃峰 小型分散式生活污水处理工艺跌水充氧方式及效率研究进展
能源与环境学院 2013.04.11 五五楼会议室 张跃峰 高效厌氧产沼气及硝化液回流脱臭污水处理工艺研究进展
能源与环境学院 2012.10.10 五五楼会议室 张跃峰 小型分散式生物生态组合工艺在不同温度下的运行效果及微生物特性研究
能源与环境学院 2010.08.18 五五楼会议室 张跃峰 太湖流域村庄生活污水治理情况
能源与环境学院 2012.10.13 无锡分校 陈文亮 多目标优化在污水处理系统工艺优化中的应用
能源与环境学院 2011.09.22 五五楼会议室 张跃峰 大阪市雨污合流制排水系统改造措施简介
日本国际协力机构(JICA) 2011.01.20 北京 竹岛 正 事后评估的意义和日本的相关事例
能源与环境学院 2012.10.12 无锡分校 Ahmed M. Osman Performance Analysis of New Bio-Ecological processes for Rural Domestic Wastewater Treatment
     
学术会议
会议名称时间地点本人报告本人报告题目
日本下水道协会第47届研究发表会 2010年7月28-29日 日本名古屋市
日本国际协力机构(JICA)深度处理/高效污水处理设施建设研修班 2010年7月25日—8月7日 日本大阪
日本国际协力机构(JICA)污水深度处理规划设计及事后评估研修班 2011年6月15日—7月1日 日本东京
第四届农村和小城镇水环境治理论坛 2014年8月7日-8日 北京 江苏省农村生活污水治理进展及对策
中国环境科学学会2015 年学术年会 2015.8.6—8.7 深圳 村庄生活污水处理适宜技术与人工湿地景观系统的构建
     
代表作
论文名称
人工湿地处理农村生活污水的脱氮影响因素
Features and performance of biological and ecological treatment combination process for rural sanita
多点交替进水阶式A2/O工艺实时控制参数研究
 
答辩委员会组成信息
姓名职称导师类别工作单位是否主席备注
姚重华 正高 教授 博导 华东理工大学
张雁秋 正高 教授 博导 中国矿业大学
仲兆平 正高 教授 博导 东南大学
杨林军 正高 教授 博导 东南大学
余冉 正高 教授 博导 东南大学
      
答辩秘书信息
姓名职称工作单位备注
邵云 其他 讲师 东南大学