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1.
土壤渗滤介质系统去除雨水径流污染物   总被引:2,自引:0,他引:2  
刘芳  侯立柱 《环境工程学报》2012,6(12):4294-4298
利用昆明当地的土壤在室内填装一个土柱渗滤系统,使用配水浓度模拟昆明市区雨水径流污染物浓度,进行去除雨水径流污染物的实验研究,考察系统对COD、TN、NH4+、NO3^-、NO2^-和TP的去除效果。实验结果表明,该土壤渗滤系统对COD平均去除率为82.04%,对TN的平均去除率为22.64%,对NH;平均去除率为94.26%,但是对NO3^-、NO2^-去除效果较差,对TP平均去除率为96.95%;另外,系统长期运行导致下渗速度降低,出水效果反而变好。  相似文献   

2.
山地城市暴雨径流污染特性及控制对策   总被引:1,自引:0,他引:1  
为了解山城重庆的暴雨径流污染特性,充实国内仍然薄弱的基础资料,对4种用地类型的4场暴雨进行了监测,测试指标包括TSS、COD、TP、TN和NH3-N。结果表明,对于坡度2.5%的交通干道和坡度30%的校园人行道,从污染物浓度降幅的角度考虑初期径流的控制量应分别为2~3 mm和1.8 mm。随降雨时间的延长,路面污染物浓度迅速降低,坡度越大,降低速率越快。对于平均浓度,校园屋顶和草坪的各污染物浓度均达到地表水环境质量Ⅴ类标准(总氮和氨氮除外)。交通干道和校园人行道的总磷平均浓度也满足地表水环境质量Ⅴ类标准,但2种下垫面的COD、TN和氨氮平均浓度分别超出地表水环境质量Ⅴ类标准的2~8倍、1.9~3.1倍和1.9~4.3倍。对于交通干道,场次降雨径流的总氮、总磷和氨氮平均浓度与初期浓度的比值和污染物浓度20 min降幅接近(分别为0.5~0.53和50%~55%)接近,而COD和TSS平均浓度与初期浓度的比值和污染物浓度20 min降幅相近(分别为0.35~0.37和78%~84%)。对于校园人行道,污染物浓度20 min降幅均达到90%以上(90%~96%),场次降雨径流的总氮、总磷、氨氮、COD和TSS的平均浓度与初期浓度的比值接近(0.3~0.4)。研究结果为山地城市暴雨径流的污染控制提供了参考。  相似文献   

3.
李继香 《环境工程学报》2014,8(7):2901-2905
实验对比考察了常规混凝和加载磁混凝工艺对微污染河水中COD、浊度和TP等污染物的去除效果,系统研究了混凝剂用量、磁种加载量、搅拌条件和药剂投加顺序等因素对加载磁混凝效果的影响。实验结果表明,加载磁种后沉淀颗粒的体积平均粒径为从常规混凝工艺的50.1μm显著增加到68.6μm;污染物去除效果明显优于常规混凝工艺,尤其对浊度和总磷的去除效果得到了显著的提升;在实验最优条件下COD、浊度和TP的去除率分别达到54.17%、99.28%和75.82%;并且加载磁种后可减少50%以上的混凝剂投加量,同时大大缩短沉淀时间。  相似文献   

4.
随着生物除磷脱氮工艺的大量使用,初沉池的设置和取消一直在学术和工程界存在争议。以重庆市某污水厂为对象,从对无机悬浮固体(ISS)、COD和TN去除效果的角度探讨了初沉池在污水处理系统的重要性。研究结果表明,在合流制排水体制下,该污水厂进水污染物浓度非常高,COD、SS和ISS的平均浓度分别为560、1 100和780 mg/L;初沉池对COD、SS和ISS的去除率分别为61%、78%和85%,对ISS的去除率比COD高20%左右;污水经过初沉池沉淀之后,ISS/COD从1.7下降到0.7左右,COD/TN从8.0左右下降到4.3,粒径由40μm下降到30μm。初沉池对大粒径的ISS具有较好的去除效果,未能被去除的小粒径ISS容易悬浮在混合液中,降低MLVSS/MLSS。从ISS/COD的削减和保持混合液MLVSS/MLSS正常的角度来讲,初沉池不应取消。  相似文献   

5.
通过中试研究了不同溶解氧浓度、有机负荷、HRT条件下,反应沉淀一体式矩形环流反应器(RPIR)对深圳市南山污水处理厂低C/N城市污水的处理效果。结果表明,在控制溶解氧浓度为1 mg/L、COD容积负荷小于2.5 kg/m3.d、NH4+-N容积负荷不超过0.2 kg/(m3.d)、HRT为4 h时,COD平均去除率可达90%,NH4+-N平均去除率超过80%。RPIR在处理该城市污水过程中具有良好的抗冲击负荷能力,污染物去除效率高,运行稳定。  相似文献   

6.
西安市城市主干道路面径流污染及沉淀特性研究   总被引:5,自引:2,他引:3  
在西安市城市主干道南二环路建立路面径流采样站,利用自制流量等比例采样装置,采集2009年3-11月的34场降雨径流,测试研究径流SS、COD事件平均浓度(EMC)、有机污染物赋存状态,并就降雨特征对径流污染的影响进行相关分析,还采用累积曲线法对16场径流水样进行沉淀实验,研究沉淀对径流中污染物的去除效果.结果表明,城市...  相似文献   

7.
采用序批式活性污泥反应器(SBR)进行好氧颗粒污泥(AGS)培养,比较仅接种普通絮状污泥培养(R1)与接种普通絮状污泥及部分厌氧颗粒污泥培养(R2)下污泥颗粒化进程、污泥特性及污染物去除特性。结果表明,通过逐渐缩短SBR沉淀时间、提高有机负荷,R1、R2分别在17、23d时出现乳白色颗粒,颗粒粒径较小(0.1~0.5mm),颗粒污泥成熟时由白色转变为黄色,污泥容积指数(SVI)均保持在40mL/g左右;培养60d时,R1、R2内污泥基本实现颗粒化,颗粒化程度分别为90.0%、84.4%;R1、R2中胞外聚合物(EPS)质量浓度均在56d时分别为84.75、64.05mg/g(以单位质量挥发性悬浮固体(VSS)中的质量计,下同),其中R1、R2中多糖(PS)在EPS中占主要比重;R1、R2中培养的AGS均具有密实的结构和良好的沉降性能,对污染物具有良好的去除效果,培养后期R1、R2对COD平均去除率分别为96%、94%,对TN平均去除率分别为60%、56%,对TP平均去除率分别为65%、61%。R2中接种的部分厌氧颗粒污泥可能对EPS的分泌起到一定抑制作用,从而影响污泥的颗粒化进程。  相似文献   

8.
水力负荷对人工湿地修复富营养化景观水体效果的影响   总被引:1,自引:0,他引:1  
水力负荷对湿地的去污效果有直接影响,但目前的研究一般限于去除率方面,缺少对污染物去除总量影响的研究。为综合考察水力负荷对人工湿地修复富营养化景观水体效果的影响,以某会议中心富营养化景观水体生态修复工程中的2#人工湿地为研究对象,研究了其在水力负荷分别为1.03、1.37m/d时的水质净化效果。结果表明:当水力负荷由1.03m/d提高到1.37m/d时,2#人工湿地仍具有较好的COD、TN和TP去除效果;COD和TN的总平均去除率略有下降,但水力负荷为1.37m/d时的COD和TN总平均去除量比水力负荷为1.03m/d时总平均去除量分别高28.29%和20.96%,对COD和TN总量的控制效果显著;TP的去除受水力负荷的影响较小,在两种水力负荷条件下均具有较高的去除率。  相似文献   

9.
以新型间歇增氧垂直流人工湿地(IA-VFCW)为研究对象,揭示了不同工况对人工湿地污染物去除的分层效应及去除效果的影响.结果 表明:不同曝气参数对细砾石层、煤渣层污染物去除的影响较小;对曝气区、湿地植物区污染物去除的影响较大.当进水NH4-N质量浓度为25 mg·L-1、COD为200 mg·L-1时,细砾石层、煤渣层对NH4+-N和TN平均去除率分别为10.8%、9.3%和13.3%、11.6%,两区域中均无NO2-N、NO3-N的积累;细砾石层对COD去除的贡献较大,COD平均去除率为67.2%.曝气区对NH4-N、TN去除贡献较大,NH4-N、TN的最大去除率分别达到69.3%、40.9%,COD平均去除率为25.4%.在低曝停比下,曝气量的增加将提高IA-VFCW对TN的去除性能;在高曝停比下,曝气量的增加会降低IA-VFCW对TN的去除效果,且会造成NO--N积累.在曝气量2 m3·h-1、曝停比1/3、曝停周期6h工况下IA-VFCW具有较好的污染物去除效果,NH4+-N去除率为94.9%、TN去除率为77.0%、COD去除率为90.0%.IA-VFCW脱氮性能明显优于传统垂直流人工湿地.  相似文献   

10.
植物种类与水力负荷对人工湿地去除污染物的交互作用   总被引:1,自引:0,他引:1  
人工湿地去污效能不仅受水力负荷(HL)影响,还与植物种类有关。为研究这2种因素对污染物去除的交互作用,根据植物根系长度,分别构建短根型、中根型及长根型植物潜流人工湿地中试系统,在运行稳定后,考察不同植物种类在不同水力负荷(152、230、305和460 mm/d)下的去污效果。结果表明:植物种类对COD去除率的影响差别不显著,对氮磷去除率有显著影响,且去除率符合长根型中根型短根型;水力负荷对COD、TN、NH_4~+-N和TP的去除均有显著影响,随着水力负荷减小去除率均逐渐升高;植物种类与水力负荷的交互作用对各污染物去除率均有显著影响,且受水力负荷影响较大,TN、NH_4~+-N的去除在水力负荷较小时交互作用较明显,COD去除的最优HL为230 mm/d。因此,在人工湿地设计时应考虑植物种类与水力负荷的交互作用。  相似文献   

11.
This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).  相似文献   

12.
底泥修复中温度对微生物活性和污染物释放的影响   总被引:9,自引:1,他引:9  
通过分析底泥中微生物的酶活性以及污染物的释放规律,探讨了温度对河道底泥生物修复的影响.结果表明,底泥中微生物的脱氢酶、脲酶和磷酸酶的活性随着温度的升高而显著增大,但温度对纤维素酶的活性影响较小.4 ℃和10 ℃时底泥中污染物的释放量和微生物的酶活性均较低,水质较稳定;20~37 ℃时底泥中污染物的释放量明显增加,微生物的新陈代谢能力有较大提高,水体的自净能力较强.在各种因素的综合作用下,20~30 ℃是进行底泥生物修复的适宜环境温度.此外,当pH为9.0以及添加葡萄糖时,底泥中微生物均表现出较高的脱氢酶活性.  相似文献   

13.
This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a “primus motor” for the governance of the mitigation of eutrophication in the Baltic Sea.  相似文献   

14.
The increasing production and use of plastic in the Arabian Gulf combined with shipping and waste disposal practices, have increased the concentration of plastic particles on the sea's surface and beaches. The objective of this investigation was to provide an assessment of the abundance, distribution, potential sources and significance of industrial plastic on the western beaches of the United Arab Emirates on the Arabian Gulf and on the eastern beaches on the Gulf of Oman. The abundance of stranded plastic pellets was highly uneven. By early 1992 alarming levels of fresh plastic pellets were noticed on the Arabian Gulf beaches of the UAE. Large numbers of 25 kg sacks of white plastic spherules manufactured by (SABIC) in Jubail, Saudi Arabia were washed ashore. When compared to the west coast on the Arabian Gulf, the east coast on the Gulf of Oman exhibited much lower levels of plastic pellets. When compared to other parts of the world, the beaches of the UAE on the Arabian Gulf are considered to be heavily polluted with industrial plastic.  相似文献   

15.
This study assesses the growth of the microalgae Nannochloris oculata in the presence of lindane and the ability of N. oculata to remove lindane from media. Algal biomass increased with 0.1 and 0.5 mg L?1 of lindane, and lindane concentrations in the media decreased. N. oculata removed 73% and 68.2% of lindane in the 0.1 and 0.5 mg L?1 media concentrations, respectively. Algal biomass decreased to the level of the control at lindane concentrations greater than 2.5 mg L?1, probably due to toxicity. N. oculata removed lindane from the media at concentrations lower than 1.0 mg L?1. Thus, N. oculata may be useful for lindane bioremediation in contaminated aquatic systems.  相似文献   

16.

In the present study, the endocrine activity of the antiepileptic pharmaceutical carbamazepine (CBZ) in the crustacean Daphnia magna was assessed. To assess the hormonal activity of the drug, we exposed maternal daphnids and embryos to environmental relevant concentrations of CBZ (ranging from 10 to 200 μg/L) and to mixtures of CBZ with fenoxycarb (FEN; 1 μg/L). Chronic exposure to CBZ significantly decreased the reproductive output and the number of molts of D. magna at 200 μg/L. This compound induced the production of male offspring (12?±?1.7 %), in a non-concentration-dependent manner, acting as a weak juvenile hormone analog. Results showed that this substance, at tested concentrations, did not antagonize the juvenoid action of FEN. Further, CBZ has shown to be toxic to daphnid embryos through maternal exposure interfering with their normal gastrulation and organogenesis stages but not producing direct embryo toxicity. These findings suggest that CBZ could act as an endocrine disruptor in D. magna as it decreases the reproductive output, interferes with sex determination, and causes development abnormality in offspring. Therefore, CBZ could directly affect the population sustainability.

  相似文献   

17.
A study was made of the influence of the application of sewage sludge on the degradation of pesticides in the soil. Two kinds of sludge were used, with different characteristics, one from an urban treatment plant and one from a food processing plant. Three organophosphorus insecticides, fenitrothion, diazinon and dimethoate, were studied. The relative importance was determined of the chemical and biological degradation processes, which involved experiments on soil and sterile soil samples. A comparative study was also made of the degradation of pesticide residues and the evolution of the microbial population. The application of sludge seems to have a complex effect on the degradation of pesticides, determined by the bioavailability and biodegradability of their active ingredient. The biodegradation of pesticide residues brings about alterations in the microorganism population of the soil.  相似文献   

18.
Adani F  Ricca G  Tambone F  Genevini P 《Chemosphere》2006,65(8):1300-1307
Humic acid consists of a recalcitrant (unhydrolysed fraction) (the core) and labile (hydrolysable fraction) fraction. Core-humic acid (core-HA) isolation was performed by treating source material with apolar and polar solvents (organic solvents+acid hydrolysis) before alkaline extraction. Leonardite, soil Ah horizont and dry blood were chosen for this study because of their different origin and degree of humification. Chemical analysis (elemental analysis, total acidity, E(4):E(6)), spectroscopic analysis (DRIFT and (1)H NMR), and complete mass balance were used to investigate the effect of purifying humic acids. The results obtained showed that purification produced a slight modification of Leonardite humic acids as was expected for these highly humified organic matrices. On the other hand, about 500 g kg(-1) of soil humic acids were lost by purification. The fractions lost mainly consisted of carbohydrates. Dry blood showed the presence of humic acids that contrasted with its origin, thus indicating the limitations of the common analytical methods used for HA extraction. Nevertheless, in practice, purification caused the complete disappearance (914 g kg(-1) of HA was lost) of these HAs. The results obtained in this work suggest that the HA fraction isolated (named core-HA) effectively represents the HA structure proposed by the existing literature, since the purification proposed was able to eliminate the adsorbed organic molecules (interference materials) coating the HA structure.  相似文献   

19.
阐述了环境保护与党的执政能力建设的内在联系。论述了加强环境保护是增强“党的领导能力”的题中之意;加强环境保护是“坚持把发展作为党执政兴国的第一要务,不断提高驾驭社会主义市场经济的能力”的重要内容;环境保护关系到社会和谐与国家安全。环境保护工作者应全面分析和妥善应对来自各方面的机遇和挑战,促使环境发展矛盾由“两难”向“双赢”转化,走生产发展、生活富裕、生态良好的文明发展之路。  相似文献   

20.
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