电絮凝集成技术及应用研究进展.pdf

第49卷 第 9 期2023 年 9 月Vol.49 No.9Sept.,2023水处理技术水处理技术TECHNOLOGY OF WATER TREATMENT电絮凝集成技术及应用研究进展电絮凝集成技术及应用研究进展祝海涛1，2（1.杭州水处理技术研究开发中心有限公司，310012；2.蓝星（杭州）膜工业有限公司，311103：浙江 杭州）摘摘 要要:介绍了电絮凝原理及集成技术在水处理领域中的应用研究进展，作为一种利用电解产生的金属离子及其多核羟基络合物和氢氧化物将溶液中污染物进行凝聚、吸附与氧化的水处理技术，电絮凝具有去除效率高、操作控制简便、污泥产出量少、处理成本低等优点。指出电絮凝与其他水处理工艺组合可进一步提高污染物去除效率并降低系统能耗，认为未来电絮凝集成技术研究主要集中于电絮凝集成工艺关键环节强化以及与集成工艺匹配的电絮凝设备结构优化，从而发挥组合工艺优势，提高系统处理能效。关键词关键词:电絮凝;集成技术;优化;水处理开放科学开放科学（资源服务资源服务）标识码标识码（OSID）:中图分类号中图分类号:X703.1 文献标识码文献标识码:A 文章编号文章编号:10003770(2023)09-0007-004随着化工、电镀、制药、纺织等各行业的快速发展，大量工业废水也在加工生产中不断产生，若不对其进行妥当处理，将对生态环境与人类健康造成严重危害1。据统计全球三分之二的人口每年至少有一个月生活在严重缺水的条件下，约5亿人常年面临严重的水资源短缺，水环境问题已成为制约人类发展的关键性问题2-4。近年来，各级政府对环保要求不断提高，企业陆续采用废水资源化处理系统对工业废水进行除杂与再利用，积极响应和落实国家关于绿色低碳发展的指导思想。因此，废水处理技术受到越来越广泛的关注。其中，电化学废水处理技术因具有产生污泥少、无需化学添加剂、占地面积小且不影响处理水质等优点，被广泛应用于重金属废水、含油废水、屠宰废水、含硅废水等处理工艺中5-8。电絮凝又被称为电凝聚或电混凝，它是在化学混凝及电解的基础上发展起来的一项水处理技术。早在19世纪80年代末，电絮凝在英国首次被应用于污水处理中，迄今已有130余年的历史9；1906年，电絮凝技术在德国取得了第一项专利10；1946年，电絮凝技术在美国被应用于饮用水处理中，但因供电成本高和技术不成熟最终未能得到广泛应用11。到21世纪初，随着电力行业的发展及废水处理的需求，电絮凝技术再次成为水处理工艺的研究热点。目前，关于电絮凝的基础研究已基本趋于完善，下一阶段主要是对强化电絮凝的摸索研究。强化电絮凝是对传统电絮凝技术中的某个或几个环节进行优化或强化，包括电源技术、电极技术和集成技术等，从而进一步提升废水处理效果。本文概述了电絮凝原理及优点，重点讨论了电絮凝与其他水处理工艺的集成研究，提出电絮凝集成技术未来的主要研究方向，为电絮凝废水处理工艺优化提供有益借鉴。1 电絮凝原理及优点电絮凝原理及优点电絮凝工艺一般采用可溶性阳极（铁、铝等）作为极板，在直流电的作用下，阳极被溶蚀，产生铁、铝等离子，再经一系列水解、聚合及氧化过程，发展形成各种羟基络合物及多核羟基络合物，使废水中的胶体、悬浮物等杂质絮凝沉淀，从而实现分离与去除效果12-13。电絮凝以吸附沉降为主，氧化还原为辅，是吸附、絮凝、氧化还原、气浮分离等多种过程协同作用的结果，不仅对胶体和悬浮杂质具有凝聚沉淀作用，而且由于阳极的氧化作用和阴极的还原作用，对废水中其他污染物也有协同去除作用。DOI:10.16796/ki.10003770.2023.09.002收稿日期：2023-03-15基金项目：浙江省重点研发计划（2021C04002）作者简介：祝海涛（1990），男，博士，高级工程师，研究方向为废水处理与资源化；电子邮件：7第 49 卷 第 9 期水处理技术水处理技术电絮凝技术相较于化学混凝及其他水处理方法，具有如下优点14-18：1）电絮凝无需添加其它化学试剂，实现原位反应，出水水质好，污泥量产生少且含水量低，降低污泥的处置费，同时也实现废水的绿色节能处理；2）电絮凝处理废水过程产生的氢氧化物比化学絮凝所用的絮凝剂活性高，形成的胶粒具有较强絮凝能力，且絮体颗粒稳定，沉降性能好易于分离，同时电解产生的气泡有利于吸附悬浮颗粒，对污染物具有更好的去除效果；3）电絮凝装置设计紧凑，占地面积小，操作维护方便，易实现自动化操作，设备处理时间短，处理效率高且稳定；4）电絮凝工作电流小，运行能耗低，而且可通过燃料电池、太阳能和风能等绿色能源进行发电。2 集成技术集成技术目前，电絮凝在废水处理中通常与其他水处理技术进行联用，充分发挥电絮凝的优势，提高废水处理能效，在高效去除废水污染物的同时进一步降低系统能耗。电絮凝集成技术结合各类水处理工艺，为各种类型废水的实际处理提供更多选择，扩大可处理污染物的范围，提高电絮凝技术在工程应用中的实际价值。2.1电氧化电氧化-电絮凝技术电絮凝技术电氧化法作为高级氧化法中的一种，对有机污染物的深度处理具有显著效果，因此通过联用电絮凝发挥各自优势，不仅可以提升污染物去除效率，还能进一步降低能耗。DAI等19提出一种新型掺硼金刚石作为阳极和铝作为阴极的集成电化学氧化-电絮凝系统，能同时去除废水中的悬浮物和抗生素，该系统对模拟四环素废水的浊度和四环素去除率分别为67.4%和95.48%，对模拟磺胺甲恶唑废水的浊度和四环素去除率分别为71.25%和99.78%，与单独的电絮凝或电氧化相比，集成系统具有空间利用率高、能耗低、适用范围广、成本低等优点。SONG等20开发了电氧化-电絮凝联合反应器，使用RuO2-IrO2/Ti和Al电极处理Cu-EDTA废水，在电流密度为10.29 mA/cm2、0（NaCl）为1 g/L、0（Cu）为50 mg/L、pH为7的条件下，反应60 min后Cu和COD去除率分别达到99.85%和85.01%，证明了电氧化-电絮凝工 艺 是 处 理 Cu-EDTA 废 水 的 有 效 方 法。CHOUDHURY等21采用电氧化和电絮凝相结合的一体化电化学处理方法对厌氧消化池中高浓度渗滤液的有机负荷和氮负荷进行研究，与单一的电氧化相比，该工艺对氨氮、总凯氏氮和总氮的去除能力分别提高了 33%、27%和 24%，COD 的去除率达到95%98%，且能耗更低，这对于有机废水高效处理具有重要的借鉴意义。2.2电絮凝电絮凝-膜技术膜技术膜分离技术作为水处理领域的一项新兴技术，具有节能环保、化学试剂用量少、占地面积小、操作简单、易与其它技术集成等优点，包括超滤、纳滤、反渗透、电渗析等。OULEBSIR等22采用电絮凝-纳滤组合工艺对含阿莫西林的药物废水进行处理，考察电流强度、操作压力、pH和浓度等关键工艺参数，在最佳条件下阿莫西林的去除率可达到98.2%，同时能耗大幅降低；通过引入电絮凝预处理整个工艺处理 效 率 更 高，并 有 效 延 长 纳 滤 膜 使 用 寿 命。SARDARI等23将电絮凝耦合超滤技术用于处理家禽废水，废水的TSS、COD和BOD去除率分别达到100%、92%和98%，并且废水杂质经过电絮凝的预先去除，超滤膜的渗透通量在处理过程中衰减减少。废水经过电絮凝预处理后再进入膜系统，电絮凝处理产水达到膜的进水要求，有效减缓膜污染，提高膜通量24，因此电絮凝与膜分离集成耦合工艺在废水近零排放及资源化处理中具有广阔发展前景。另外，AKARSU等25采用电絮凝-膜分离工艺处理护理用品废水，通过研究电絮凝电极材料、电流密度、初始pH、停留时间等参数及后续膜分离工艺，发现通过电絮凝耦合超滤和反渗透膜，COD去除率从只采用电絮凝处理的79.91%提升至电絮凝-超滤-反渗透处理的99.18%，同时表面活性剂、油脂和微塑料的去除率也均显著提高。2.3超声超声-电絮凝技术电絮凝技术超声-电絮凝技术因其成本低、过程快、效率高等特点受到众多研究者的关注。超声技术能够有效提高电絮凝处理污染物过程的整体性能，在电絮凝过程中超声可以破坏沉积在电极表面的固体层，同时减小双电层的厚度，减缓电极板的钝化现象，进一步活化电极及电极反应区的离子，从而提升电絮凝的处理效果26-28。SADEGHI等29采用超声-电絮凝法处理含砷地下水，通过调控pH值、初始浓度、反应时间、电极间距及电流密度等参数使废水中砷的去除率提升至98.5%。ZYONAR等30对比了超声、电絮凝以及超声耦合电絮凝三种工艺对染料废水中色度和COD去除率的影响，发现超声处理的增加明显有助于电絮凝处理效果的提升，电絮凝对RR 2418祝海涛，电絮凝集成技术及应用研究进展染料废水的 COD 和色度去除率分别为 83.1%和91%，在相同条件下通过超声耦合电絮凝处理后，COD和色度去除率分别提高至99%和99.9%，并且超声耦合电絮凝工艺还能有效减缓电极钝化，达到高污染物去除率的同时反应时间更短。2.4电絮凝电絮凝-生物技术生物技术生物处理技术常用于去除废水中的有机成分，具有操作简单、经济实用等优点。然而，大多数工业废水除了含有悬浮固体和胶体物质外，还含有不可生物降解的有害污染物，这会严重降低生物处理效率，因此目前采用电絮凝进行预处理，对不可生物降解的污染物进行有效去除31。DEVECI等32采用电絮凝耦合生物真菌处理工艺去除皮革废水中的Cr6+和有机物，探究电解时间、电流密度、生物处理时间、pH和接种量对皮革废水处理效果的影响，通过响应曲面法得出在最优条件下 COD和 Cr6+的去除率分别为96%和97%，而且该组合工艺相较于皮革废水的传统处理方法更为经济。ROY等33采用生物氧化-电絮凝耦合工艺去除地下水中的砷，与传统电絮凝系统相比，一体化生物氧化-电絮凝系统不仅对砷具有更好的氧化去除效果，而且铁用量仅为传统工艺的十分之一，因此污泥产出量更少，能耗也更低，具有更好的经济效益和应用潜力。2.5电絮凝电絮凝-浮选技术浮选技术电絮凝对污染物的去除过程包括电化学反应、气浮沉降等，因此研究者通过浮选技术强化电絮凝的气浮过程，促进包含污染物的絮凝物上浮至液面上层，改善固液分离效果，进一步提升对废水中污染物的处理效能34。ABDULRAZZAQ等35采用在电絮凝中引入微气泡的方法处理染料废水，实验结果表明微气泡具有浮力，而且表面积和体积比率高，有助于快速去除污染物，可大幅提高染料的降解效率，通过优化pH、电流密度、气泡流量、电解/浮选时间等操作参数，染料去除率可达96%，而无气泡系统去除率仅为70.75%。BRACHER等36采用电絮凝-浮选系统处理生活污水，通过考察电流、电解时间、电极间距和初始pH等关键参数，表明电絮凝-浮选技术能够高效去除色度、COD、浊度等，并且产水水质达到城市污水回用标准。因此，电絮凝-浮选耦合工艺对工业废水和生活污水都具有良好的去除效果，而且经济实用利于推广。但是，目前电絮凝-浮选过程还有众多难题需要探索和突破，例如絮凝体与气泡的作用方式、絮凝体形态与气泡尺寸和稳定性的匹配及气浮与电絮凝影响因素的同步有效控制等研究。3 结结 语语为了进一步提高电絮凝去除污染物效率并降低系统能耗，研究学者通过电絮凝技术与其他水处理工艺进行集成，对电絮凝过程进行强化或优化。但是，目前电絮凝集成工艺对废水处理的规模较小，还没发展到工业规模应用的阶段，在集成装置放大及组合工艺优化方面缺乏系统研究。因此，今后电絮凝集成技术研究重点主要有：1）根据电絮凝反应机理，明确需强化或优化的工艺环节，提高对废水的净化效果；2）优化与集成工艺匹配的电絮凝设备结构，提升电化学反应及絮凝体分离效率，完善改进设备的成套设计；3）结合水质特性研究可选择的可处理工艺，达到组合工艺的优势互补，提高系统处理能效，扩大可处理污染物范围，满足实际工程应用要求。参考文献：1YAQUB M,LEE W.Zero-liquid discharge(ZLD)technology for resource recovery from wastewater:A reviewJ.Science of the Total Environment,2019,681:551-563.2MEKONNEN M M,HOEKSTRA A Y.Four billion people facing severe water scarcityJ.Science Advances,2016,2(2):e1500323.3AKTER S,SUHAN M B K,ISLAM M S.Recent advances and perspective of electrocoagulation in the treatment of wastewater:A reviewJ.Environmental Nanotechnology,Monitoring&Management,2022,17:100643.4TAHREEN A,JAMI M S,ALI F.Role of electrocoagulation in wastewater treatment:A developmental reviewJ.Journal of Water Process Engineering,2020,37:101440.5KHANDEGAR V,SAROHA A K.Electrocoagulation for the treatment of textile industry effluent-A reviewJ.Journal of Environmental Management,2013,128:949-963.6熊道文,王合德,刘利军,等.电絮凝法用于重金属废水处理研究进展J.环境工程,2013,31(S1):61-65.7DAS P P,SHARMA M,PURKAIT M K.Recent progress on electrocoagulation process for wastewater treatment:A reviewJ.Separation and Purification Technology,2022,292:121058.8POTRICH M C,DUARTE E D S A,SIKORA M D S,et al.Electrocoagulation for nutrients removal in the slaughterhouse wastewater:comparison between iron and aluminum electrodes treatmentJ.Environmental Technology,2022,43(5):751-765.9LU J B,ZHANG P,LI J.Electrocoagulation technology for water purification:An update review on reactor design and some newly concerned pollutants removalJ.Journal of Environmental Management,2021,296:113259.10 KARHU M,KUOKKANEN V,KUOKKANEN T,et al.Bench scale electrocoagulation studies of bio oil-in-water and synthetic 9第 49 卷 第 9 期水处理技术水处理技术oil-in-water emulsionsJ.Separation and Purification Technology,2012,96:296-305.11 STUART F E.Electronic water purification progress report on the electronic coagulator-a new device which gives promise of unusually speedy and effective resultsJ.Water Sewage,1946,84:24-26.12 HAKIZIMANA J N,GOURICH B,CHAFI M,et al.Electrocoagulation process in water treatment:A review of electrocoagulation modeling approachesJ.Desalination,2017,404:1-21.13 BRILLAS E,MARTINEZ-HUITLE C A.Decontamination of wastewaters containing synthetic organic dyes by electrochemical methods.An updated reviewJ.Applied Catalysis B:Environmental,2015,166-167:603-643.14 SAPRYKINA M N.A new design of the electrocoagulation apparatus for removal of micromycetes from waterJ.Journal of Water Chemistry and Technology,2012,34(5):240-245.15 AL-SHANNAG M,AL-QODAH Z,BANI-MELHEM K,et al.Heavy metal ions removal from metal plating wastewater using electrocoagulation:Kinetic study and process performanceJ.Chemical Engineering Journal,2015,260:749-756.16 MOLLAH M Y A,MORKOVSKY P,GOMES J A G,et al.Fundamentals,present and future perspectives of electrocoagulationJ.Journal of Hazardous Materials,2004,114(1):199-210.17 DARBAN A K,SHAHEDI A,TAGHIPOUR F,et al.A review on industrial wastewater treatment via electrocoagulation processesJ.Current Opinion in Electrochemistry,2020,22:154-169.18 NAWARKAR C J,SALKAR V D.Solar powered electrocoagulation system for municipal wastewater treatmentJ.Fuel,2019,237:222-226.19 DAI C C,CHEN D H,WU J,et al.Construction of a novel integrated electrochemical oxidation-coagulation system for simultaneous removal of suspended solids and antibioticsJ.Chemical Engineering Journal,2022,447:137505.20 SONG P P,SUN C Y,WANG J,et al.Efficient removal of Cu-EDTA complexes from wastewater by combined electrooxidation and electrocoagulation process:Performance and mechanism studyJ.Chemosphere,2022,287:131971.21 CHOUDHURY M R,RAJAGOPAL R,MEERTENS W,et al.Nitrogen and organic load removal from anaerobically digested leachate using a hybrid electro-oxidation and electro-coagulation processJ.Journal of Environmental Management,2022,311:114761.22 OULEBSIR A,CHAABANE T,TOUNSI H,et al.Treatment of artificial pharmaceutical wastewater containing amoxicillin by a sequential electrocoagulation with calcium salt followed by nanofiltrationJ.Journal of Environmental Chemical Engineering,2020,8(6):104597.23 SARDARI K,ASKEGAARD J,Y-HCHIAO,et al.Electrocoagulation followed by ultrafiltration for treating poultry processing wastewaterJ.Journal of Environmental Chemical Engineering,2018,6(4):4937-4944.24 GAMAGE N P,CHELLAM S.Aluminum electrocoagulation pretreatment reduces fouling during surface water microfiltrationJ.Journal of Membrane Science,2011,379(1):97-105.25 AKARSU C,ISIK Z,MBAREK I,et al.Treatment of personal care product wastewater for reuse by integrated electrocoagulation and membrane filtration processesJ.Journal of Water Process Engineering,2022,48:102879.26 戴常超,陈大宏,刘峻峰,等.强化电絮凝技术的基础、现状和未来展望J.工业水处理,2022,42(01):1-14.27 PRAJAPATI,A K.Sono-assisted electrocoagulation treatment of rice grain based distillery biodigester effluent:Permance and cost analysisJ.Process Safety and Evironmental Protection,2021,150:314-322.28 ASAITHAMBI P,YESUF M B,GOVINDARAJAN R,et al.Distillery industrial wastewater(DIW)treatment by the combination of sono(US),photo(UV)and electrocoagulation(EC)processJ.Journal of Environmental Management,2022,320:115926.29 SADEGHI H,MOHAMMADPOUR A,SAMAEI M R,et al.Application of sono-electrocoagulation in arsenic removal from aqueous solutions and the related human health risk assessmentJ.Environmental Research,2022,212:113147.30 ZYONAR F,GKKUS,SABUNI M.Removal of disperse and reactive dyes from aqueous solutions using ultrasound-assisted electrocoagulationJ.Chemosphere,2020,258:127325.31 AL-QODAH Z,AL-QUDAH Y,OMAR W.On the performance of electrocoagulation-assisted biological treatment processes:a review on the state of the artJ.Environmental Science and Pollution Research,2019,26(28):28689-28713.32 DEVECI E,AKARSU C,GNEN,et al.Enhancing treatability of tannery wastewater by integrated process of electrocoagulation and fungal via using RSM in an economic perspectiveJ.Process Biochemistry,2019,84:124-133.33 ROY M,GENUCHTEN C M,RIETVELD L,et al.Integrating biological As(III)oxidation with Fe(0)electrocoagulation for arsenic removal from groundwaterJ.Water Research,2021,188:116531.34 INOSTROZA C,BAHRAOUI N E,RIVERA-TINOCO R,et al.Uses of electro-coagulation-flocculation(ECF)for the pre-concentration of microalgae biomassJ.Process Biochemistry,2022,122:1-7.35 ABDULRAZZAQ N N,AL-SABBAGH B H,SHANSHOOL H A.Coupling of electrocoagulation and microflotation for the removal of textile dyes from aqueous solutionsJ.Journal of Water Process Engineering,2021,40:101906.36 BRACHER G H,CARISSIMI E,WOLFF D B,et al.Performance of an electrocoagulation-flotation system in the treatment of domestic wastewater for urban reuseJ.Environmental Science and Pollution Research,2022,29(32):49439-49456.（下转第33页）10万琼等，包埋厌氧氨氧化菌的影响因素与研究现状Influencing Factors and Research Status of Encapsulated Anammox BacteriaWAN Qiong,LI Lingyi,ZHANG Xinyan,YANG Guohong,LU Linrui,JU Kai*(School of Municipal Engineering,Xian University of Science and Technology,Xian 710054,China)Abstract:Compared with the traditional activated sludge method,the use of embedded anammox technology can increase the cell concentration in the reactor,shorten the start-up time,promote solid-liquid separation,and improve the impact resistance of the system.This paper mainly expounds on the various methods of microbial immobilization technology and their advantages and disadvantages.The influences of carrier material,sludge morphology,cross-linking agent and other environmental factors on the encapsulation of anammox bacteria were further expounded.And the research status of this technology in the treatment of pollutants in water was summarized.Finally,the development prospect of embedded anammox technology was predicted,and its restrictive factors were discussed.Keywords:immobilization;embedding;anammox bacteria;influencing factors;biological denitrificationResearch Progress of Electrocoagulation Integration Technology and ApplicationZHU Haitao1,2(1.Hangzhou Water Treatment Technology Development Center Co.,Ltd,310012;2.Bluestar(Hangzhou)Membrane Industries Co.,Ltd,311103:Hangzhou,China)Abstract:The principle of electrocoagulation and the application of integration technology in water treatment were introduced.As a kind of water treatment technology that uses metal ions generated by electrolysis and their polynuclear hydroxyl complexes and hydroxides to coagulate,adsorb and oxidise pollutants in solution,electroflocculation has the advantages of high removal efficiency,simple operation and control,low sludge output and low treatment cost.It was pointed out that the combination of electrocoagulation and other water treatment processes can further improve the pollutant removal efficiency and reduce the system energy consumption.It was also proposed that the future research of electrocoagulation integration technology mainly focuses on strengthening the key links in the integrated process and optimizing the structure of electrocoagulation equipment matched with the integrated process,so as to give full play to the advantages of combined process and improve the system energy efficiency.Keywords:electrocoagulation;integration technology;optimization;water treatmentSynthesis of Single Atom Catalysts and Treatment of Emerging Contaminants in Water:A ReviewLIU Zhen1,2,ZHENG Peng1,LIU Lang1,JI Fangfang3,YUAN Shaochun1,2,CHEN Yao1,2(1.Engineering Laboratory of Environmental Hydraulic Engineering of Chongqing Municipal Development and Reform Commission,Chongqing Jiaotong University,400074;2.School of River and Ocean Engineering,Chongqing Jiaotong University,400074;3.T.Y.Lin International Engineering Consulting(China)Co.,Ltd.,401121:Chongqing,China)Abstract:Single atom catalysts(SACs)have been widely used in the treatment of emerging contaminants in water due to their unique and stable structure,flexible and simple preparation methods,and high atom utilization.The SACs have great potential in achieving high activity and selectivity catalytic reactions.At present,the synthetic methods of SACs are multifarious,and their application in water purification still needs more study.In view of this situation,this review discussed the main synthesis methods of SACs and their application in the degradation of emerging contaminants.The