【作者】 田卫；

【导师】 董德明；

【作者基本信息】 吉林大学 ， 环境科学， 2004， 硕士

【摘要】 采用人工湿地进行污水净化的研究与应用始于70年代未期，1996年在奥地利维也纳召开的第四届人工湿地国际研讨会标志着人工湿地系统作为一种独特新型废水处理技术正式进入水污染控制领域。目前它被应用于生活污水、工业废水、矿山及石油开采废水、农业点源和非点源以及水体富营养化的治理。西欧、北美等国家已建立了大量的人工湿地，但国内应用实例还很少，在处理城市污水方面目前仅有深圳沙田、山东胶南、辽宁沈阳3座人工湿地处理厂。人工湿地是个完整的生态系统，它是由水体、基质（由土壤、细沙、粗砂、砾石等构成）、水生植被（以芦苇、香蒲为主）和微生物四个基本组成要素构成的，能够利用基质微生物、植物这个复合生态系统的物理、化学和生物的协同作用，通过过滤、吸附、共沉、离子交换、植物吸收和微生物分解来实现对废水的高效净化，实现废水的资源化与无害化，属于一种生态治理污水的方法。人工湿地污水处理系统分为：表面流人工湿地、潜流人工湿地、垂直流人工湿地3种类型。其中前两种在实际中均有应用的实例，而垂直流人工湿地尚无应用实例的报道，处于小试研究之中。根据我国目前已建成的人工湿地城市污水处理厂的实际情况，人工湿地对污染物去除效率是较高，其中表面流人工湿地系统主要污染物去除效率：COD为80%，BOD5为86%，SS为91%，TN为64%，TP为75%，主要污染物排放浓度符合国家污水二级排放标准要求。即从净化效果来看，人工湿地可与常规生物处理法相媲美，而其投资约为常规生物处理法的1/6～1/3，运行费用仅为其1/7～1/4，但人工湿地占地面积<WP=69>较大，约为常规二级生化污水处理厂面积的4～6倍。人工湿地处理技术适合我国国情，尤其适合广大农村、中小城市的污水处理以及非点源污染治理，特别是在干旱、半干旱及土地盐碱化地区适宜构建表面流人工湿地处理工业废水和城市污水；有可利用的池塘或闲地、且二级处理出水不能满足水环境要求的城市，可选用表面流人工湿地对城市污水处理厂符合一级或二级的出水进一步进行深度净化处理，再排放或作为景观用水等；对于湖泊周边的农田径流和农田退水等非点源的治理也应以表面流人工湿地为主。但潜流人工湿地比较适合于处理水量不大、较分散的污水，但其管理要求较高，。一般的小城镇和农村以及寒冷地区也不适宜建潜流人工湿地。表面流人工湿地占地面积大，因此，在土地价格高的城市或土地资源欠缺的地区是不宜单独采用表面流人工湿地处理工业污水或城市污水土地盐碱化是吉林省西部重大的生态环境问题之一，且西部经济欠发达，缺少资金治理污水，大量生活污水和工业废水没有得到有效治理，超标排放，使湖、塘、河流等水环境受到较大的污染。盐碱地的渗透系数较小，具有较好的隔污能力，且西部地广人稀，有很好的条件构建表面流人工湿地，这不仅可有效解决污水超标排放污染问题，而且也是西部污水资源化的有效途径，因此，建议吉林省西部各市、县可在盐碱地上构建表面流人工湿地处理城市污水和企业工业废水，污水冬季可存放于人工湿地、盐碱地或泡中，春季解冻后再进入人工湿地。处理后的出水可作为农田灌溉水，或水塘（泡）中作为景观用水，或排入盐碱地中，改善其生态环境。吉林省大部分河流流量以及环境容量较小，即使污水达标排放，也不能保证河流满足指定标准功能要求。如建有或正在建设污水处理<WP=70>厂的长春市、双阳区、四平市、延吉市、桦甸市、辽源市、通化市等，即使污水处理达标排放，其污水的受纳水体伊通河、双阳河、条子河、布尔哈通河、辉发河、东辽河、浑江等江河仍不能满足规定的地表水功能要求。由于中水处理的投资和运行费以及回用配套设施投资均较高，一般城市很难承受。因此，可构建表面流人工湿地，使污水处理厂出水得到深度净化处理后再排入河流或作为景观用水，这是解决河流水质不满足功能要求问题的有效途径之一。长春某厂表面流人工湿地面积为0.52hm2，其有机负荷为67kgBOD/ hm2.d，停留时间为0.58d，通过实测，主要污染物净化效率：SS约为65%，BOD5约为33%，COD约为29%，NH3-N约为12%。20℃时BOD的降解系数K20约为0.80d－，COD降解系数K20约为0.67d－。在寒冷的冬季，处理工业污水的表面流人工湿地系统是可以正常运行的，但去除效率有所下降。人工湿地是正在不断得到研究应用和发展的污水处理实用新技术，具有投资低，出水水质好、抗冲击力强、改善和美化生态环境、操作简单、维护和运行费用低廉等优点，可作为常规的污水生物处理技术的一种有效替代方案，其完全不同于传统的氧化塘，且在污染物净化效率及应用前景方面优于好氧塘。但目前国内对人工湿地这项技术的研究应用尚处于起步阶段，有关工艺设计资料和应用实例还不多见，在北方还存在冬季气温低和植物枯萎等因素造成的处理能力减弱问题，尤其是表面流人工湿地处理系统所需占地面积很大，有待结合我国不同地区的具体情况，深入开展研究工作，取得适合于不同地区、不同环境气候条件及不同污水特性的实用数据，以促进人工湿地处理技术在我国适当地区的推广应用。更多还原

【Abstract】 The study and application of wastewater treatment with constructed wetland started in the end of 1970s. The 4th international conference on constructed wetland in Vienna, Austria symbolized that as a kind of special new wastewater treatment technology, constructed wetlands started to enter the fields of water pollution and water control. By now, it was widely applied to treat municipal wastewater, industrial wastewater, mineral wastewater, oil exploit wastewater, non-point resource pollution and eutrophication treatment. Many of countries in west Europe and North America have constructed plenty of wetlands. However, applied engineering examples are lack of in China, only in Shenzhen, Guangdong province, Jiaonan, Shandong province, Shenyang, Liaoning province 3 constructed wetland wastewater treatment plant were built. As a complete ecosystem, constructed wetland is made of water, medium (soil, silver sand, coarse sand, gravel etc.), vegetation (reed, cattail) and microbe realize effective wastewater purification utilizing multi-ecosystem’s cooperation process of physical, chemical and biological through filtration, adsorption, deposition, ion exchange, vegetation assimilation and microorganism decomposition. It belongs to a kind of ecological technology of wastewater treatment. Constructed wetlands can be divided into 3 types, surface flow constructed wetland, subsurface flow constructed wetland, vertical flow constructed wetland. Among these 3 types, former 2 types both have engineering application, while vertical flow constructed wetland has no been reported on its application, still in pilot-scale study stage.The practical situation of wastewater treatment plant had been built in our country demonstrated that the pollutant removal efficiency of <WP=72>constructed wetland was high. The efficiency of surface flow constructed wetland is: COD (80%), BOD5 (86%), SS (91%), TN (64%), TP (75%). The concentration of effluent from constructed wetland can meet the second level standard. As for the purification effect, constructed wetland can be alternative to conventional biological treatment technology, but it is equivalent to 1/6～1/3 in invest, 1/7～1/4 in operation and maintenance of conventional biological treatment. However, constructed wetland needs large lands, about 4～6 times of conventional secondary biochemical treatment plant.Surface flow constructed wetland in the Changchun Carriage Factory occupied area 0.52hm2. Its organic load is 67kg BOD/ hm2.d and hydrological retention time (HRT) is 0.58d. Determination data demonstrated that treatment efficiency of main pollutants in this system is: SS (65%), BOD5 (33%), COD (29%), NH3-N (12%). In 20℃, the decomposition coefficient of BOD is 0.80d-1 and of COD is 0.67 d-1. The practice showed that even in cold winter, the system still is operational, but its efficiency drops down a little. The surface flow constructed wetland in the Changchun Carriage Factory derived from an aerobics pond, so it is not a typical example of industrial wastewater treatment through surface flow constructed wetland.Constructed wetland wastewater treatment technology is suitable to our country, especially in expansive village, small-middle scale city, adopting it to treat wastewater and non-point source pollution. In arid, semi-arid and salt-alkalization area, it is feasible to constructed wetland to treat industrial and municipal wastewater. This technology is adoptable in those cities where have useable land or pond, when the first or secondary effluent cannot meet water environmental require and need to be polished for landscape use. Non-point source pollution from runoff and effluent of <WP=73>farmland also should mainly adopt surface constructed wetland. Subsurface flow constructed wetland is feasible for small volume and disperse wastewater, at the same time it need strict management. General small town, village and cold climate area are not suitable to construct subsurface flow constructed wetland. Sole Surface constructed wetland shouldn’t be adopted to treat indus更多还原