潜流人工湿地水力设计浅议

人工湿地水处理技术人为创建拟自然条件,利用自然界微生物学、生物学、物理和化学过程来处理污水,在发达国家应用非常广泛,目前我国对人工湿地的设计还没有形成规范化的标准和导则,系统地论述了EPA人工湿地手册中潜流人工湿地的水力设计理论、步骤等,并针对其局限性提出了改进措施,以期为国内的人工湿地工程设计提供技术参考。     

潜流人工湿地水力设计浅议

人工湿地水处理技术是模拟自然条件人为创建湿地,利用自然界微生物学、生物学、物理和化学过程来处理污水。在发达国家应用非常广泛。目前我国对人工湿地的设计还没有形成规范化的标准和导则。着重论述EPA人工湿地手册中潜流人工湿地的水力设计理论、步骤等,并针对其局限性提出了改进措施,以期为国内的人工湿地工程设计提供技术参考。     

季节变化对人工湿地净化城市湖泊水体的影响

以西安市兴庆湖为研究对象,研究了季节变化对人工湿地净化城市湖泊水体效果的影响.结果表明:人工湿地对污染物的去除效果受季节变化的影响较大,秋季湿地对CODCr的去除率比冬季高19.58％,对TN的去除率比冬季高33.79％,而对TP去除率的影响不明显,对NH3 -N的去除率比冬季低20.03％.     

潜流人工湿地系统水力设计原则及类型

水力学条件是潜流型人工湿地建立及维持最重要的决定因子,直接关系人工湿地污水处理系统中的流速、流态、停留时间以及与植物生长关系密切的水面线控制等水力因子的设计和确定。概括分析了潜流型人工湿地水力设计的原则和类型,提出了复合潜流人工湿地系统水力模型构建的方法,以及形成系统的水流条件控制方法的研究路线,以期为潜流人工湿地优化设计、优化运行及机理模型的建立提供理论基础。     

人工湿地对化粪池出水净化效果的研究

通过在同种基质上种植相同数目的芦苇,研究了垂直流人工湿地对化粪池出水的净化效果以及不同水力停留时间对污水净化效果的影响。结果表明,同种填料、不同水力停留时间对污水中TP、NH3-N、COD的净化效果不同。由于芦苇根系和微生物的吸收与分解作用以及基质的吸附作用,种植芦苇的人工湿地的出水水质要比没种芦苇的好。     

高水力负荷人工湿地的研究

为了提高北方地区人工湿地的运行效果和使用范围,采用提高水位和增加填料层厚度的方式来实现湿地的高水力负荷,从而在减小湿地面积的同时增加湿地的去污能力。实验中采用的是五级串联复合湿地,结果表明,在温度逐渐降低的秋季,在水力负荷为0.8 m3/m2·d,水力停留时间为24 h时,湿地系统对TN的平均去除率在42.45%左右;对亚硝酸盐氮的平均去除率在95%左右;对TP的平均去除率在94%左右;pH值由8.34降到了8.03左右。其中在第二级潜流湿地的去污效果最显著,之后呈缓慢下降的趋势。由此可见提高水位和增加填料层厚底可以有效地提高人工湿地的去污效果,同时解决人工湿地占地面积大的问题。     

污染物浓度和水力负荷双重作用下人工湿地的净化效果

研究从徐州地区大沙河西人工湿地基地中筛选6种挺水植物系统和2种沉水植物作为室内实验的供试植物,从丰县康达污水处理厂出水取样作为实验用水,研究人工湿地的水生植物对不同污染程度水体和水力负荷条件下的净化能力.研究可为人工湿地的实际运行和处理效果提供理论依据.     

人工湿地的除污机理及进一步提高氮磷去除率的方法

人工湿地作为一种生态型污水处理新技术,在实践中得到了成功的应用。人工湿地对氮、磷总体的去除率虽然比传统的生物技术要高得多,但氮的去除效果仍然不很高,一般的人工湿地对氮的去除率为60％左右。本文论述了人工湿地的除污机理,及进一步提高氮、磷去除率的几种方法。     

人工湿地深度处理医院污水的研究

以人工湿地系统处理医院污水处理站二级处理出水,以达到深度降解并去除TN的目的。设计总面积782 m2人工湿地系统,其中自由表面流型(FWS)人工湿地450 m2和潜流型(SSF)人工湿地186 m2,最后连接生态景观池面积146 m2,每日平均抽取30 m3污水(二级处理出水),水力负荷为0.05 m/d。早期运行结果显示,TN去除率为44%,NO3-—N去除率FWS湿地为15%,SSF湿地为34%。试验进行到稳定运行期,调高流量至70～100 m3/d,水力负荷为0.11～0.16 m/d,结果显示,NO3-—N去除率达68%;比较FWS与SSF湿地的NO3-—N的去除速率,FWS湿地为2.48 g/(m2.d),SSF湿地为3.61 g/(m2.d)。SSF湿地对NO3-—N的去除效能比FWS湿地好。     

水力条件对芦苇湿地系统DO质量浓度的影响

就水位及水力负荷对湿地系统中DO质量浓度的影响进行实验。结果表明：随着水位的不断提高,芦苇湿地系统中的DO质量浓度呈现出不断升高的趋势,且在300～550 mm水位区间增加趋势比较明显,随着水位的再度升高,在550～650 mm水位区间DO质量浓度增加趋势趋于平稳;随着水力负荷的不断增加,芦苇湿地系统中的DO质量浓度呈现先增加后减小的趋势,本实验中最适合的水力负荷在0.8968～1.2230 m3/（ m2＆#183; d）之间。     

Effect of loading rate on performance of constructed wetlands treating an anaerobic supernatant.

The effect of organic loading, season and plant species on the treatment of fish farm effluent was tested using three-year old mesocosm wetland systems. During one year, nine 1 m2 mesocosms (horizontal subsurface flow), located in a controlled greenhouse environment, were fed with a reconstituted fish farm effluent containing a high fraction of soluble components (1,600 microS/cm and in mg/L: 230 +/- 80 COD, 179 +/- 60 sCOD, 100 +/- 40 TSS, 37 +/- 7 TKN, 14 +/- 2 TP). Combinations of three hydraulic loading rates (30, 60 and 90 L.m(-2) d(-1)) and two plant species (Phragmites australis, Typha angustifolia) and an unplanted control were tested for treatment performance and hydraulic behaviour. Loadings higher than 15 g COD m(-2) d(-1) resulted in a net decrease of hydraulic performances (generation of short circuiting) coupled with low TKN removal. Maximal TKN removal rates (summer: 1.2, winter: 0.6 g.m(-2) d(-1)) were reached in planted units. In all mesocosms, phosphorus was removed during summer (maximal removal rate: 0.3 g TP m(-2) d(-1)) and was released in winter (release rate = approximately half of summer removal rate). This study confirmed that constructed wetlands are susceptible to clogging when treating anaerobic storage tank supernatant rich in highly biodegradable compounds. Contributions of plants to hydraulic efficiency were mainly observed in summer, associated with high evapotranspiration rates. Both plant species gave a similar removal efficiency for all pollutants.     

Effect of polyaluminium chloride on phosphorus removal in constructed wetlands treated with swine wastewater

Total phosphorus (TP) removal in aged constructed wetlands poses a challenge, especially when treated with swine wastewater with high concentrations of phosphorus (P). Our earlier studies with anaerobic lagoon swine wastewater treatment in constructed wetlands showed a decline in P removal (45-22%) with increased years of operation. These particular wetlands have been treated with swine wastewater every year since the first application in 1997. Preliminary lab-scale studies were conducted to evaluate the efficiency of polyaluminium chloride (PAC) in the removal of phosphate-P (PO4-P) from swine wastewater. The experimental objective was to increase the phosphorus treatment efficiency in constructed wetland by adding PAC as a precipitating agent. PAC was added by continuous injection to each wetland system at a rate of 3 L day(-1) (1:5 dilution of concentrated PAC). Swine wastewater was added from an anaerobic lagoon to four constructed wetland cells (11m wide x 40m long) at TP loads of 5.4-6.1 kg ha(-1) day(-1) in two experimental periods, September to November of 2008 and 2009. Treatment efficiency of two wetland systems: marsh-pond-marsh (M-P-M) and continuous marsh (CM) was compared. The wetlands were planted with cattails (Typha latifolia L.) and bulrushes (Scirpus americanus). In 2008, PAC treatment showed an increase of 27.5 and 40.8% of TP removal over control in M-P-M and CM respectively. Similar trend was also observed in the following year. PAC as a flocculant and precipitating agent showed potential to enhance TP removal in constructed wetlands treated with swine wastewater.     

沸石床复合垂直流人工湿地脱氮机理分析

通过研究沸石床复合垂直流人工湿地中不同形态氮的空间变化,分析了其脱氮机理,认为沸石对NH_3—N的吸附作用是脱氮的重要途径,硝化和反硝化作用提高了TN的去除率,硝化和反硝化强度影响到沸石的饱和周期和生物再生,有待进一步研究。     

水平潜流人工湿地脱氮除磷研究进展

总结了水平潜流人工湿地的脱氮除磷机理,分析了进水水质、植物、基质、温度和水力停留时间这5种影响处理效果的主要因素,从不同角度论述了提高脱氮除磷效果所采取的措施,并探讨了水平潜流人工湿地存在的局限性和发展趋势。     

浑河沈抚段水体污染季节性变化研究

为明确浑河沈抚段水污染特征,提升水环境治理有效性,2015年3月—2016年2月对浑河沈抚段进行水环境调查。根据丰、平、枯3个水期的pH值、电导率、COD、NH_3-N、BOD及COD_(Mn)等水质指标,运用改进的综合水质标识指数法识别出主要污染因子,并分析浑河沈抚段水质污染时空变化特征。结果表明,研究区域的pH值在一个水文年变化范围为6.42~8.06,较适宜水生生物生长;水体在枯水期的电导率最高,丰水期最低。浑河沈抚段水体受沿岸工业废水和生活污水的点源污染影响,流域枯水期和平水期各监测断面的综合水质均未达标;从上游到下游4项水质指标的综合水质指数增大,污染逐渐加重,主要污染指标为COD和NH_3-N。     

Influence of design, physico-chemical and environmental parameters on pharmaceuticals and fragrances removal by constructed wetlands

The ability of several mesocosm-scale and full-scale constructed wetlands (CWs) to remove pharmaceuticals and personal care products (PPCPs) from urban wastewater was assessed. The results of three previous works were considered as a whole to find common patterns in PPCP removal. The experiment took place outdoors under winter and summer conditions. The mesocosm-scale CWs differed in some design parameters, namely the presence of plants, the vegetal species chosen (Typha angustifolia versus Phragmites australis), the flow configuration (surface flow versus subsurface flow), the primary treatment (sedimentation tank versus HUSB), the feeding regime (batch flow versus continuous saturation) and the presence of gravel bed. The full-scale CWs consisted of a combination of various subsystems (ponds, surface flow CWs and subsurface flow CWs). The studied PPCPs were ketoprofen, naproxen, ibuprofen, diclofenac, salicylic acid, carbamazepine, caffeine, methyl dihydrojasmonate, galaxolide and tonalide. The performance of the evaluated treatment systems was compound dependent and varied as a function of the CW-configuration. In addition, PPCP removal efficiencies were lower during winter. The presence of plants favoured naproxen, ibuprofen, diclofenac, salicylic acid, caffeine, methyl dihydrojasmonate, galaxolide and tonalide removal. Significant positive correlations were observed between the removal of most PPCPs and temperature or redox potential. Accordingly, microbiological pathways appear to be the most likely degradation route for the target PPCPs in the CWs studied.     

人工湿地处理四环素类抗生素废水时有机碳源的影响

研究了以葡萄糖和乙酸钠为碳源的条件下,垂直流人工湿地对四环素(TC)、土霉素(OTC)和金霉素(CTC)等3种四环素类抗生素(TCs)的去除效果。结果表明,在试验条件下,乙酸钠与葡萄糖两种碳源均能有效促进人工湿地系统对3种TCs的去除;在相同碳源条件下COD质量浓度越高,TCs的去除率越高,当COD质量浓度大于400mg/L时,对3种TCs的去除率均达到90%以上;垂直流人工湿地对TCs的去除过程包括2个阶段:前2 h为湿地基质吸附作用下的快速去除阶段,2~24 h为缓慢去除阶段。乙酸钠与葡萄糖两种碳源对TCs去除率的提高,主要发生在2h之后的第二个阶段,分析认为发生了微生物共代谢作用,促进了湿地系统对基质吸附富集之后的TCs的进一步降解。     

额尔古纳河洪水淹没模拟及湿地植被变化分析

额尔古纳河是中俄两国界河,缺乏完整的地形数据,难以使用常规方法建立水动力学模型。USGS3s分辨率（约30m）的DEM数据是共享数据,但局部精度略低,本文使用从Google Earth图像提取的河道和湿地数据,修正了这一数据集,获得了这条无资料界河的地形数据。通过一维非恒定流水动力学模型MIKE11的模拟获得了年最大洪水淹没面积,将从2000年9月TM遥感图像提取的湿地范围同模型模拟的同年最大洪水淹没范围进行比较,二者吻合程度较高,前者几乎是后者的外包络,说明经修正的DEM数据基本可用。由MODIS EVI数据提取的2000—2009年增强型植被指数年最大值（YEVI）结果显示额尔古纳河干流区间二卡-黑山头段近10年湿地植被存在明显退化的趋势,并且YEVI与年最大洪水淹没面积间存在显著的正相关关系。研究结果表明洪水是改善额尔古纳河流域湿地植被的一个正向驱动力。     

人工沉床对TN的去除效果及其影响因素

建立一种模块化气浮调节式人工沉床,并应用于重富营养化水体的生态修复,在天津市外环河进行现场试验。结果表明:当停留时间为5.48 d时,人工沉床对TN的去除率在植物生长期内(3—10月)可达到35%~40%;冬季(11月至次年2月)可达到5%~15%。TN浓度随停留时间的变化符合一级动力学方程,相关系数R2均在0.9以上。衰减系数随水温的变化趋势符合S形增长曲线,即在水温过低和水温过高时,水温的变化对衰减系数的影响并不大,但在某一适当温度范围内,水温的上升将导致衰减系数的快速增加。     

改良型人工快渗系统脱氮除磷效果研究

人工快渗(CRI)系统是一种广为人知的无动力生态处理技术措施,但传统CRI系统存在对氮、磷去除率普遍较低的问题。本研究采用海绵铁、沸石、火山岩、红壤土和杂沙作为填料,构建了一个改良型CRI系统,在水力负荷为1 m~3/(m~3·d)的条件下,以实际生活污水为试验进水,进行为期20天的试验。实验结果表明,该系统在运行16天后出水TP、TN和NH_3-N浓度均趋于稳定,稳定后出水平均浓度分别为0.21 mg/L、8.38 mg/L和2.34 mg/L,能分别满足《城镇污水处理厂污染物排放标准》(GB18918-2002)一级A排放标准的0.5 mg/L、15 mg/L和5 mg/L的限值。TP、TN和NH3-N三项指标的总平均去除率为84.44%,远高于传统CRI系统的44.06%总平均去除率。该研究成果为治理农村生活污水提供了一项行之有效的生态治理技术措施。