人工土壤渗滤对颗粒COD的吸附及堵塞.pdf

人工土壤渗滤对颗粒 COD的吸附及堵塞 ＊ 孙宗健 丁爱中 滕彦国 北京师范大学水科学研究院, 教育部水沙重点实验室, 北京 100875 摘要 生活污水中颗粒 COD 占到总 COD 的 30～ 60, 砂滤试验证实, 非生物参与的单纯过滤仅能去除总 COD 的 20～ 35。 人工土壤渗滤对颗粒 COD 的吸附是通过系统介质表层的快速接触-吸附完成的, 通常 80以上吸附量集 中在表层 20 cm 之内。 对颗粒 COD 的吸附是人工土壤渗滤系统堵塞的主要原因, 微生物增长量占到系统孔隙率的 3. 7～ 5. 3。 通过对系统入渗及恢复试验, 得到系统干湿交替运行的合适配搭, 对人工土壤渗滤防堵塞和长期稳定 运行提供了有益探索。 关键词 土壤渗滤 颗粒 COD 污水处理 吸附 堵塞 ＊“十一五”科技支撑重大项目子课题 2006BAJ04A07 。 0 引言 在人工土壤渗滤等生态工程应用中 , 颗粒 COD 往往是造成系统堵塞的主要成分 [ 1] 。生活污水中颗 粒COD含量一般比较高 [ 2] , 这种情况下, 如果让大部 分颗粒 COD 进入生物处理系统, 不仅微生物对其降 解起来较困难 ,而且极易造成系统的堵塞 [ 3] 。因此, 研究颗粒 COD 在生活污水中的比例、土壤渗滤对颗 粒COD 的去除以及由此造成的堵塞, 对于污水生态 处理系统非常重要。 事实上,人工土壤渗滤不仅可以有效地去除 SS, 而且对颗粒COD也具有一定的去除效果。污水中大 部分颗粒 COD 可被截留 、 吸附在渗滤介质的表面 [ 4] , 剩余的可生物降解的部分颗粒 COD 也可以通过微生 物降解得以部分去除 [ 5] 。 1 污水中颗粒 COD 的测定 根据颗粒 COD 的定义 , 测试过程中将其视为悬 浮物, 按照悬浮物的测定方法 , 将水样通过孔径为 0. 45 μ m的滤膜 [ 6] 。测定滤出液的 COD 浓度 ,将其视 为溶解性 COD,用原水的 COD 浓度减去溶解性 COD 即为颗粒 COD 的浓度。 测定中使用抽滤装置 包括抽滤漏斗、 抽滤瓶 、 真 空泵 以及 CTL-12 型化学需氧量测定仪。 2 单纯利用粗砂过滤对颗粒 COD 的去除 试验选取了两种砂, 一种是人工粉碎加工的石英 砂,另一种是建筑砂 两种砂均经过160 ℃下烘烤2 h 的干热灭菌法处理 。 2. 1 污水中颗粒COD的含量 试验的生活污水取自某下水管道主管道 ,污水中 颗粒 COD 含量试验结果见表 1。 表 1 生活污水中颗粒 COD 含量 原水总 ρ COD mgL- 1 溶解性 ρ COD mgL- 1 颗粒 ρ COD mgL - 1 颗粒COD 含量 764. 2235. 1529. 169. 2 303. 6190. 1113. 537. 4 366. 0188. 1147. 947. 0 478. 6320. 2158. 433. 1 由表 1 中数据可以看出 , 颗粒 COD 在生活污水 中的含量随原水的浓度变化而变化, 其含量一般在 30～ 60。 2. 2 试验结果 试验结果见表 2。 表 2 单纯砂滤试验结果 项目原水 建筑砂 过滤 石英砂 过滤 微孔 过滤 ρ COD mgL- 1 303. 6240. 4197. 6190. 2 总COD 去除率 20. 834. 937. 4 颗粒COD 去除率 55. 893. 5100 试验结果表明 , 砂滤对于颗粒 COD 具有很好的 去除 ,主要颗粒直径为 0. 1～ 0. 3 mm的石英砂对颗粒 COD的去除高达 93. 5, 而颗粒较粗的建筑砂对颗 粒COD的去除也达到了 55. 8。 由于试验进行前 ,对试验用砂进行了干热灭菌处 理,而且试验过程中污水渗滤速度很快 , 建筑砂和石 英砂的渗透速度分别为30. 26和10. 08 m s。基本上可 以认为渗滤过程几乎没有微生物对 COD 的降解去除 作用发生, 总 COD 的去除主要是由渗滤介质对颗粒 39 环 境 工 程 2008年 12 月第 26卷第 6 期 COD的过滤 、吸附作用得到去除。建筑砂和石英砂 对总COD的去除分别为 20. 8和 34. 9。因此, 可 以判定颗粒COD 的去除不仅与原水中颗粒 COD 的含 量有关,而且与渗滤介质的性质有关。渗滤介质的比 表面积越大 、 孔隙直径越小, 颗粒 COD的去除效果也 越好 ,同悬浮物的去除基本一致。 3 人工土壤渗滤吸附颗粒 COD 的试验 3. 1 试验设计 试验选取了一种比较粗的石英砂作为人工土壤 渗滤的填料介质 ,并添加石灰石、少量矿石和活性炭 及营养物质等构成人工土壤渗滤的人工土壤层。 砂粒度分析结果见表 3 ,人工土壤结构示意图见 图1 。 表 3 石英砂的粒度分析结果 粒径 mm石英砂 2～ 1. 435. 91 1. 43～ 0. 932. 23 0. 9～ 0. 657. 59 0. 6～ 0. 454. 01 0. 45～ 0. 30. 20 0. 3～ 0. 20. 05 0. 2～ 0. 10. 00 0. 1～ 0. 0740. 00 6时 ,湿地出水溶解氧质量浓度基本维持 在0. 73～ 0. 8 mg L 。 2 在气水比为 6 时, 人工湿地各污染物的去除 率达到最大 , COD 去除率为 85. 6, TP 去除率为 70. 9, TN 去 除 率 为 83. 1, NH3- N 去 除 率 为 84. 2。出水 NO - 3- N 质量浓度最低, 为6. 32 mg L。 曝气能够很好地解决人工湿地脱氮效果不佳的问题。 3 曝气在一定程度上打破了人工湿地长期以来 无动力的运行模式, 使人工湿地处理效果具有明显的 改善 ,尤其是湿地的脱氮效果 。 参考文献 [ 1] Armstrong W, Cousins D. Oxygen distribution in wetland plant roots and permeability barriers to gas -exchange with the rhizosphere a microelectrode and modelling study with phragmites australis. Annals of Botany , 2000,86 3 687 -703 [ 2] 彭青林, 敖洁, 曾经. 水生植物塘中的溶解氧变化及对污水处理 研究. 长沙电力学院学报 自然科学版 ,2004, 19 1 79 -82 [ 3] 王宜明. 人工湿地净化机理和影响因素探讨. 昆明冶金高等专 科学校学报, 2000, 16 2 1 -6 [ 4] Ronald D Delaune, Reza Pezeshki . Effects of soil oxidation -reduction conditions on internal oxygen transport , root aeration, and growth of wetland plants Proceedings of a Conference on Sustainabilityof Wetlands and Water Resourses. USA University of Mississippi ,2000 [ 5] 张甲耀. 潜流型人工湿地污水处理系统的研究. 环境科学, 1998,19 4 36 -39 [ 6] 贺锋. 复合垂直流人工湿地污水处理系统硝化与反硝化作用. 环境科学, 2005, 26 1 49 作者通信处 钟秋爽 210013 南京市虎踞北路 12号综合楼南三楼 电话 025 83738129 E -mail zqs827tom. com 2008- 03-11 收稿 上接第 41页 [ 3] Felde K V , Kkunst S. N and COD removal in vertical -flow systems. Wat. Sci . Tech. , 1997, 36 5 79 -85 [ 4] Poach M E, Hunt P G,Reddy G B, et al.Effect of intermittent drainageonswinewastewatertreatmentbymarsh -pond -marsh constructed wetlands. Ecological Engineering, 2007 30 43-50 [ 5] Healy M G , Rodgers M, Mulqueen J. Treatment of dairy wastewater using constructed wetlands and intermittent sand filters. Bioresource Technology , 2007 98 2268 -2281 [ 6] 梁威, 周巧红, 成水平, 等. 构建湿地基质微生物与净化效果及 相关分析. 中国环境科学, 2002, 22 3 282 -285 [ 7] Johnathan R, Bumgarnera, John E, et al. Estimating biozone hydraulic conductivity in wastewatersoil -infiltration systemsusinginverse numerical modeling . Water Research, 2007 41 2349 -2360 作者通信处 孙宗健 100875 北京师范大学水科学研究院 电话 010 62237824 2008- 04-03 收稿 44 环 境 工 程 2008年 12 月第 26卷第 6 期 INTENSIVE PHOSPHORUS REMOVAL USING TP16 WITH HIGH CAPABILITY OF ACCUMULAT- ING POLY-PChen Liwei Cai Tianming Yin Honglan et al 24 Abstract Adopting SBR reactor, andusing synthetic wastewater as materialof reactor, it was researched the capability of PHB-accumulat - ing and P -releasing under anaerobic condition, and that of PHB -decomposing and P -absorbing under aerobic condition using TP16. The result of experiment indicating When cultured in acetic acid under aerobic conditions, TP16 could accumulate PHB. Ascending of PHB concentration in the strainswas negatively correlated with descending of acetic acid concentration.While TP16 grew under anaerobic conditions, descending of acetic acid concentration in the supernatant was negatively correlatedwith ascending of PHB and P concentration. Keywords biologic phosphate accumulation biological phosphate release absorbing acetic acid accumulating PHB PROCESS OF FILTRATION AND DESALINATION FORCIRCULATED COOLING WATER FROM THERMAL POWER PLANTSYang Fengmin Zou Anhua Xing Yi et al 26 Abstract The circulated cooling water from a thermal power plant was treated by means of filtration and desalination, which could increase the concentration multiples of the circulated cooling water, also could reduce sewage water and fresh water supplement dosage, increasing water use rate in the power plants.The treatment process was comprised of the two filters, reverse osmosis desalination, and addition of chemical agents. After the processing, the reclaimed water could be used as supply water to the circulating cooling water. Keywords circulated cooling water desalination continuous dynamic filters reverse osmosis TREATMENT OF RAW BAMBOO FIBERWASTEWATER BY AIR -FLOATATIONA O PROCESS Li Song Shan Shengdao Chen Bin et al 29 Abstract The wastewater of raw bamboo fiber with high concentration and low bio -degradability was treated by air -floatationA O process. The results showed that the removal rates of COD, SS, NH 4-N and colority reached 92, 95. 4, 64. 7 and 90 respectively, so the efflu - ent met the wastewater discharge standard of industrial district.This process featured stable treatment effect, simple operation, as well as easy maintenance. Keywords air -floatation A O process raw bamboo fiber PRACTICAL STUDIES ON THE TECHNOLOGY OF THE TOTAL WASTEWATER REGENERA - TION AND REUSE INBAOTOU IRON AND STEEL CAMPARY Meng Yanxiao Hui Kegang Song Hua 31 Abstract It was studied on the choice of processflow and main parameters of totalwastewater regeneration and reuse project in Baotou Iron and Steel Group; itwas also summarized the operating practice of the main facilities for this project. Which provided experience in the planning, design and construction of other similar projects. Keywords iron and steel enterprise totalwastewater regeneration and reuse TREATMENT OF MUNICIPAL LANDFILL LEACHATE BY ANAEROBIC DIGESTION -SBR PRO- CESSGao Feng Li Chen 33 Abstract Biological nitrogen and organic matter removal of municipal landfill leachate by ASBR -SBR system was investigated. The cycle length of both reactors was 12 h.Raw wastewater was fed to ASBR for anaerobic digestion. Four sorts HRT of ASBR from 28. 8 h to 72 h were tested. The result indicated that the COD removal achieved 41. 2 and the effluent BOD5 COD and BOD5 NH 4-N ratio was 0. 41 and 4. 6 re - spectively when the HRT of ASBR was 36 h, it was in favor of aerobic biological treatment of organic matters and nitrogen. The effluent of ASBR whose HRT was 36 hwas added to SBR for further treatment. And the effluent NH 4-N of SBR was about 11 mg L, but the effluent COD concen - tration couldn t meet the discharging standard. The effluent COD could be lowered to less than 100mg L after coagulating sedimentation by PFS. Keywords municipal landfill leachate anaerobic digestion ASBR SBR TN THE TREATMENT OF LANDFILL LEACHATE BY COMBINATIONOF TWO-PHASE ANAEROBIC AND OZONE ACTIVATED CARBONHuang Guoxin Huang Jiguo Jin Aifang 36 Abstract According to the propertiesof landfill leachate, the combination process of two -phase anaerobic system, which is composedof UBF acidification reatorand UASB mechanization reator, and ozone activated carbon is used to treat landfill leachate. The results show that the optimum HRT of the UBF is 10. 3h, the acidification phenomenon of the acidification phase is not occurring and the activity of the acid-producing bacteria being better; the optimum sludge loadof the UASB is 0. 122 g gd, the function of resisting the changing load of the mechanization phase being better; the two -phase anaerobic system can stably and high efficiently remove organics, but the NH3-N removal is not ideal; the optimum dosage of activated carbon is 4. 510- 2g mL wastewater; the optimum reaction time is 120 min; the ozone activated carbon can handle organics better, de - colors prominently and has a defoaming function. Keywords landfill leachate two -phase anaerobic ozone activated carbon STUDY ON PARTICLE COD ADSORPTION AND CLOGGING IN CONSTRUCTED SOIL INFIL - TRATIONSun Zongjian Ding Aizhong Teng Yanguo 39 Abstract The percent of particle COD in total COD of domestic wastewater isbetween30～ 60, of whichonly 20～ 35 can be re - 3 ENVIRONMENTAL ENGINEERING Vol. 26, No. 6,December,2008 moved through sand infiltration test but no microbial influence.Adsorption of particle COD in constructed soil infiltration is completed by rapid contact adsorption, and above 80focuses on the surface layer within the depth of 20 cm. To seek the reason of clogging in the system, some ex - periments prove that clogging mostly results from the adsorption especially in surface layer, nevertheless microbial increment makes up 3. 7～ 5. 3 in total porosity. And so a beneficial exploration is carried out on system restoration after clogging. Which makes sure that a suitable wet- dry cycle is a good way to solve the problem. Keywords soil infiltration particle COD wastewater treatment adsorption clogging INFLUENCE OF AERATING GAS-WATER RATIO ON TREATING EFFECT OF CONSTRUCTED WETLANDZhong Qiushuang Wang Shihe Sun Xiaowen et al 42 Abstract The influence of different aerating gas -water ratio on treating effect of constructed wetland was discussed from dissolved oxygen. Seven kinds of gas-water ratios, 0, 2, 4, 6, 8, 10 and12, were selectedfor test operation condition. The result showed that aeration could make the level of DO and treating effect improve obviously, especially the removal rate of TN. Treating effect of wetlandswas bestwhen gas-water ratio was 6, and removal rate of COD, TP, TN and NH3-N was respectively up to 85. 6, 70. 9, 83. 1 and 84. 2, the concentration of NO - 3-N of the effluent was the lowest 6. 32 mg L . Keywords constructed wetland aeration gas -water ratio DO treating effect TREATMENT OF TOILET WASTEWATER FROM PARKS BY COIX CONSTRUCTED WETLAND Li Yan Zhang Jian Li Weijiang et al 45 Abstract Subsurface constructed wetland planted with Coix was used for the treatment of toilet wastewater from parks. The results showed that Coix grew well in constructed wetland. With a hydraulic loading rate of 8 cm d and a hydraulic retention time of 1. 5 d, the average removal efficiencies of COD, NH4-N, TN and TP for constructedwetlandwere 56. 4, 53. 3, 49. 8and 73. 0, respectively. While for the sys - temwithout Coix, the average removal efficiencies of COD, NH4-N , TN and TP were 46. 0, 50. 1, 49. 1 and 68. 1, respectively. Coix can be applied to constructedwetland due to its possibility of pollutants removal aswell as its higher economic benefit. Keywords Coix constructed wetland toilet wastewater NUMERICAL SIMULATION AND COAGULATION OF FLOW FIELD FOR FOLDED PLATE FLOC - CULATORZhang Bingbin YangKaiming Yang Xiaolin et al 47 Abstract FLUENT analytic software was used to numerically simulate the flow field of different angles for a foldedplate flocculator. Then it was compared the flow state of fluids in different folded plate flocculators, whose coagulation effectswere analyzed according to the design condi- tions. Finally some measures were proposed for improving and enhancing the efficiency of the flocculator, which could guide the practical engi- neering design. Keywords FLUENT folded plate flocculator numerical simulation PREPARATION OF Fe -Mg-Al COMPOSITE FLOCCULANT FOR PRETREATMENT OF LANDFILL LEACHATESang Yimin Gu Qingbao Sun Tichang et al 50 Abstract In order to get optimal preparation conditions of Fe -Mg -Al composite flocculant PFMASfor pretreatment of landfill leachate, COD removals of landfill leachate were optimaized by jar test from concentration of raw FeSO4,MgSO4and Al2 SO43, mole ratio of three salts, aging temperature, aging time and dosage. The experimental results of a landfill leachate indicated that the optimal preparation conditions of PF - MAS were as belownFeⅢ ∶ nMg Ⅱ ∶nAl Ⅲ5∶ 0. 35∶ 0. 5, aging temperature50 ℃ and aging time0. 5 h. After pretreatment by PFMAS, COD removal could reach over 60. PFMAS is a kind of inorganic macromolecular copolymer of Fe Ⅲ , MgⅡand AlⅢ , with long macromolecular chains and macrocosmic crystal structure. Keywords landfill leachate inorganic polymer flocculant copolymer of Fe Ⅲ MgⅡand Al Ⅲ COD removal rate preparation optimization THE STUDY ON THE INOCULA FOR BOD5DETERMINATION Cui Jiansheng Wang Fang Wei Fusheng 54 Abstract Three strains screened from the municipalwastewater were used to make the BOD5inocula for BOD5test. The best conditionsfor making the freeze dry power BOD5inoculawere studied. The characteristics of the BOD5inoculawere compared by test on soil leaching solution and commercial Polyseed of GGA s and the actualwastewater s BOD5determinition. The standard deviation of inocula, soil leaching solutionand polyseedwas 3. 60, 8 . 34 and 2. 87 mg L respectively in GGA s experiment, and 8. 5, 33. 2 and 6. 0 mg L in the test of actual wasterwater. Keywords Biochemical Oxygen Demand BOD5 inocula repeatability UATION AND IMPROVING ON THE S OF MONITORING COD IN SEDIMENT- LADEN RIVERHe Zhijuan Xiao Xiangqun Mao Yuxia et al 57 Abstract Based on the analysis of the characteristics of sediments in the Yellow River and the impacts of sediments on the water environ - ments, this paper analyzed the primary problem which existsinm