布洛芬和双氯芬酸在不同构型人工湿地中的去除行为研究

在酸性药物中选取常用的布洛芬和双氯芬酸为典型对象,研究其在人工湿地中的去除行为,探讨不同工艺、有无植物、不同季节对其去除效果的影响.结果表明,工艺因素对二者的去除存在显著影响.其中,布洛芬在水平潜流和垂直潜流湿地中的平均去除率(分别为69%和60%)显著高于表面流湿地(26%),而双氯芬酸在表面流湿地中的平均去除率(58%)则显著高于水平潜流和垂直潜流湿地(分别为49%和43%).植物的存在可以显著提高布洛芬的去除率,对双氯芬酸的去除则无显著影响.配对样品t检验发现两种药物在夏季与秋季的去除效率无显著差异.双氯芬酸的去除效率与DO值、COD的去除效率呈极显著负相关,而布洛芬的去除效率与基质中好氧脱氢酶活性具有较好的正相关性,可能表明,布洛芬在湿地中主要通过好氧降解去除,双氯芬酸在湿地中的主要去除途径为光降解和厌氧降解.     

人工湿地中常用填料和植物对污染物去除效果的比较

人工湿地工艺作为一种优选技术应用于流域规模的污染水处理。在此,根据人工湿地中常用填料和植物的物理、化学属性,分析其优缺点及适用性,总结出对氮、磷和COD处理效果较好的填料和植物,并提出了一系列综合优化的措施和建议。     

表面流人工湿地硝化和反硝化强度研究

通过对表面流人工湿地不同土壤层硝化反硝化强度的研究,探讨了表面流人工湿地脱氮过程中沿程硝化和反硝化作用的变化,以及不同C∶N对系统反硝化强度的影响.研究结果表明,系统可同时进行硝化和反硝化作用,硝化强度具有较明显的分层现象,表层土壤高于深层土壤.系统中沿程硝化强度呈递减趋势,硝化强度反映了氨氮去除率的大小,其去除率为68%.反硝化强度研究结果表明:深层土壤的反硝化强度略高于表层土壤;沿程1/3至1/2段最大;5倍碳源时反硝化强度最高,3倍碳源次之,不加碳源最低;但系统的反硝化强度普遍较高,保持了良好的脱氮效果.     

Cost effective management of stochastic coastal water pollution

This study develops a theoretical tool for investigating the impact on cost effective coastal water management from explicit treatment of: coastal pollutant transports, stochastic pollutant transports in the catchment areas, and wetlands as a pollutant abatement option. It is applied to a relatively well investigated estuary, Himmerfjärden, south of the Swedish capital, Stockholm. The theoretical results indicate that all three factors influence cost effective allocation of measures and associated design of economic instruments. The consideration of stochastic pollutant transports will increase costs, but the direction of influence of the other two factors cannot be determined without empirical support. The application to nitrogen transport in Himmerfjärden shows that, for target nitrogen reductions given in terms of a percentage of pre-abatement loads, the inclusion of coastal transports in the cost calculations lowers the estimated total costs for targets interpreted in terms of nitrogen loads to the marine water. The alternative investigated target interpretation was in terms of nitrogen loads to coastal waters. Depending on the ability of wetlands to abate nitrogen and to change the variance in pollutant load to the coastal recipients, costs are either increased or decreased as compared to when wetlands are excluded as nitrogen abatement options.     

生物生态耦合技术处理农村生活污水的应用研究

在对“厌氧池+跌水充氧接触氧化池+水耕蔬菜型人工湿地”生物生态耦合技术应用于农村生活污水处理进行实证研究的基础上,进一步探讨了生物与生态处理单元各自的主要去除对象和效率,为生物生态技术的合理耦合提供了依据。结果表明：在进水COD、TN、TP质量浓度波动范围为51.20~211.12,28.29~122.12,1.26~5.97mg/L时,出水平均质量浓度为15.80,5.51,0.34mg/L,出水水质达到《城镇污水处理厂污染物排放标准（GB 18918—2002）》一级A标准。污水中COD、TN、TP的78%,85%,50%的去除是在生物处理单元完成的,而TP的达标排放还必需生态处理单元的参与。整个处理技术处理效果良好,运行费用低,适合在条件允许的农村地区推广使用。     

人工湿地处理城市污水启动期运行特性

选取4种植物(鸢尾、香蒲、麦冬和美人蕉)和3种基质(炉渣、沸石和砾石),通过植物和基质的不同组合构建了7组潜流型人工湿地,研究不同植物、相同基质及不同基质、相同植物条件下,湿地处理城市污水的启动期运行特性。结果表明,对COD去除率,砾石>炉渣>沸石,美人蕉>鸢尾>香蒲>麦冬;对TN去除率,沸石>砾石>炉渣,美人蕉>香蒲>麦冬>鸢尾;对NH4+-N去除率,沸石>砾石>炉渣,香蒲>美人蕉>麦冬>鸢尾;对TP去除率,炉渣>砾石>沸石,香蒲>美人蕉>鸢尾>麦冬。植物种植前,炉渣、沸石和砾石不同基质湿地的COD去除率没有明显差异;在TN和NH4+-N的去除上,沸石远优于炉渣和砾石。植物种植后,3种基质的TP去除率在10.75%左右。鸢尾、麦冬和美人蕉3种植物湿地的COD去除率随运行历程呈上升趋势,而香蒲由于生长状况不佳,去除率呈下降趋势。美人蕉湿地TN去除率较其它3种植物湿地高,各植物湿地NH4+-N去除率差异不显著。4种植物湿地TP去除率在9.24%左右。     

人工湿地分散式污水处理系统的设计和运行

采用由预处理单元、水平潜流人工湿地单元、消毒单元和污泥干化单元组成的分散式污水处理系统对采油区生活点污水进行了处理和资源化利用。核心工艺单元水平潜流人工湿地单元的优化设计参数为:人工湿地宽20 m、长80 m,采用多段串联布置形式。分散式污水处理系统实际处理水量为92~136 m3/d,在5年的实际运行过程中,COD,BOD5,NH3-N,SS的平均去除率分别为75.9%,77.3%,96.0%,96.1%。处理后出水经消毒后的水质优于GB/T18920—2002《城市污水再生利用城市杂用水水质》标准中绿化用水的水质,可作为绿化灌溉用水回用;干化后的栅渣和污泥可作为绿化肥料使用,能实现污水的资源化利用和处理系统的零排放。     

大清河人工快速渗滤系统示范工程效果分析

以滇池流域受污染的大清河为研究对象,开展了人工快速渗滤系统（CRI）示范工程研究,根据气候条件、进水水质和运行工艺分为6个工况,以探索污染负荷和工艺参数对CRI运行性能的影响。实验结果表明：水力负荷2 m.d-1、湿干比1：1是该示范工程运行的最优工艺条件。CRI系统对有机物（COD）的平均去除率范围17.42%～63.75%;对氨氮去除效果受进水水质影响,高、低污染负荷下NH3-N去除率分别为56.71%、85.48%;CRI示范工程硝化作用较强,反硝化能力较弱,对TN的平均去除率范围为10.69%～28.29%;CRI示范工程对TP的平均去除率为27.62%,最佳工艺条件下为50.23%。CRI系统可通过对填料进行优化组合、适当增大饱水带高度,强化除磷脱氮能力。     

双台子河口湿地环境石油烃污染特征分析

以2008年10月和2009年5月2次野外调查获取的数据为基础,分析了双台子河口湿地环境石油烃污染特征. 结果表明:秋季河水石油烃污染比苇田水和稻田水严重,春季三者无显著差异,但春秋两季有92.31%地表水的ρ(石油烃)超过《地表水环境质量标准》(GB3838—2002)Ⅲ类标准;湿地表层土壤秋季33.33%的站位、春季77.78%的站位达到中等及以上污染水平,春季个别站位达到重度污染水平,分布于流域中上游的盐渍水稻土和盐化草甸土污染程度比流域下游的滨海沼泽盐土和滨海潮滩盐土严重,中下游芦苇湿地对石油烃净化作用明显;剖面土壤w(石油烃)最大值出现在30~≤40 cm土层,达重度污染水平,显示双台子河口湿地环境已经受到不同程度的石油烃污染. 湿地土壤w(石油烃)与芦苇长势参数的相关分析显示,目前湿地土壤石油烃污染尚未影响芦苇的正常生长及产量,但研究区域的石油工业污染已经成为双台子河口湿地重要的生态风险源之一.      

Removal of tetrachlorobisphenol A and the effects on bacterial communities in a hybrid sequencing biofilm batch reactor-constructed wetland system

SBBR-CW system was proposed to effectively treat wastewater containing TCBPA. CW unit contributed more than SBBR to the removal of TCBPA. TCBPA changed the composition and structure of bacterial community in the system. GAOs massively grew in SBBR, but did not deteriorate TP removal efficiency. Tetrachlorobisphenol A (TCBPA) released into the sewage may cause environmental pollution and health risk to human beings. The objective of this study was to investigate the removal of TCBPA and bacterial community structures in a laboratory-scale hybrid sequencing biofilm batch reactor (SBBR)-constructed wetland (CW) system. The results showed that the removal efficiency of chemical oxidation demand (COD), ammonia, total nitrogen and total phosphorus in the SBBR-CW system was 96.7%, 97.3%, 94.4%, and 88.6%, respectively. At the stable operation stage, the system obtained a 71.7%±1.8% of TCBPA removal efficiency with the influent concentration at 200 mg/L. Illumina MiSeq sequencing of 16S rRNA gene revealed that the presence of TCBPA not only reduced the bacterial diversity in the SBBR-CW system, but also altered the composition and structure of bacterial community. After the addition of TCBPA, Proteobacteria increased from 31.3% to 38.7%, while Acidobacteria and Parcubacteria decreased greatly in the SBBR. In contrast, Acidobacteria replaced Proteobacteria as the dominant phylum in the upper soils of CW. The results indicated that TCBPA stimulated the growth of GAOs in the SBBR without deteriorating the phosphorus removal due to the presence of sufficient carbon sources. The ammonia oxidizing bacteria, Nitrosomonas, and denitrification bacteria, Hyphomicrobium and Pseudomonas, were inhibited by TCBPA, resulting in a decreasing the removal efficiency of TN and ammonia.