膜分离技术在垃圾渗滤液处理中的应用罗丹，晏云鹏，全学军

垃圾渗滤液是一种重污染的有毒有机废水,对生态环境造成了严重的威胁。本文综述了垃圾渗滤液现有的膜处理技术,与传统处理工艺相比,膜技术具有低能高效等优点,是未来渗滤液处理技术的重要发展方向。由于垃圾渗滤液组成的复杂性,根据不同处理目的,微滤膜（MF）、超滤膜（UF）、纳滤膜（NF）和反渗透膜（RO）4种膜在垃圾渗滤液处理中都得到了一定的应用。总结发现,其中MF和UF对渗滤液的处理效果较差,一般作为渗滤液的预处理技术;NF和RO对渗滤液的处理效果较好,主要作为其深度处理技术。然而,膜污染阻碍了膜技术在渗滤液处理方面的发展与应用,为此可通过研究开发新型膜材料、有效的预处理技术和膜分离工艺优化等方面来防止膜污染的发生,以便膜技术在渗滤液及其他水处理方面得到更加广泛的应用。     

膜技术在饮用水除砷中的应用研究进展

以低压驱动膜的微滤膜(MF)与超滤膜(UF),和高压驱动膜的反渗透膜(RO)与纳滤膜(NF)为主,分析了目前国内外膜技术在饮用水除砷方面的效果、影响因素、浓水处理、膜污染及其清洗等方面的应用研究和进展情况,同时对膜技术优缺点及其在除砷中的应用研究方向与前景做了展望.     

纳滤法处理垃圾渗滤液的研究进展

介绍了进年来国内外在NF法处理垃圾渗滤液方面的研究进展,主要包括混凝、MBR的预处理控污技术和对膜透过液、浓缩液的后续处理技术。分析了NF膜分离溶质的作用机理,并认为机理模型的研究和NF膜进水预处理及出水的后续处理是下一步的研究重点。     

集成膜技术处理微污染水的工艺研究

采用0.45μm微滤膜、不同截留分子质量的超滤膜(100、80、50,30.10、5 kDa)以及不同型号的纳滤膜(NF90、NF270、NF70)为试验用膜,并将这些膜进行优化组合,直接处理浙江省某流域河水.结果表明,采用0.45μm微滤膜、截留分子质量5kD的超滤膜作为预处理工艺,经NF90处理后,COD_(Mn)去除率达到89%,离子的去除率达到83%.采用直接膜处理工艺,可用微滤、超滤替代传统给水处理中的混凝、过滤、沉淀及澄清处理等微污染水预处理工艺,集成膜分离技术能很好地实现对微污染原水的彻底处理,出水水质稳定安全,完全达到健康饮用水标准.     

MBR用于垃圾渗滤液处理的国内研究及应用现状

膜生物反应器是一种将膜分离技术和生化反应器相结合的新型高效污水处理技术,在垃圾渗滤液的处理和应用方面具有重要意义。阐述了MBR工艺在处理垃圾渗滤液方面的国内最新研究进展及存在的问题;分析了膜污染问题及其控制方法;预测MBR工艺在垃圾渗滤液处理方面具有广阔的应用前景。     

UASB—MBR—NF/RO工艺处理焚烧发电厂垃圾渗滤液

针对某垃圾焚烧发电厂垃圾渗滤液的特点,采用上流式厌氧污泥床(UASB)—外置式膜生物反应器(MBR)—NF/RO组合工艺进行零排放处理,设计处理规模为300 m³/d。运行结果表明,UASB—MBR—NF/RO组合工艺对COD、NH₃-N和电导率的去除率分别为99.98%、99.97%、95.36%。出水水质COD≤13.9 mg/L、NH₃-N≤0.69 mg/L、Cl^-≤175.19 mg/L,均满足《城市污水再生利用工业用水水质》(GB/T 19923—2005)中敞开式循环冷却水系统补水标准要求。采用UASB—MBR—NF/RO工艺处理垃圾渗滤液时,UASB阶段的COD去除率为89.70%,MBR阶段的NH₃-N去除率为98.64%,NF/RO阶段的电导率去除率为92.69%。运行数据表明,该组合工艺中,COD主要在UASB中被去除,MBR主要去除NH₃-N,NF/RO系统主要对污水进行脱盐并进一步去除污水中的离子。该组合工艺运行稳定,污染物去除率...     

垃圾渗滤液生化出水絮凝-纳滤处理及过程机理

垃圾焚烧发电厂渗滤液是一种含高浓度腐殖酸类物质和高盐含量的复杂有机废水, 传统生化处理后仍难达标排放。本工作围绕垃圾渗滤液生化出水的特性, 开展了Ca(OH)₂絮凝、臭氧氧化预处理与NF处理相结合的处理工艺, 并对处理过程的机理进行了探讨。研究表明, 渗滤液生化出水经过Ca(OH)₂絮凝处理, 可以有效地去除其中的杂环类化合物。生化出水经8 g·L^-1的Ca(OH)₂絮凝处理后, 比MBR出水产水通量提高达8.2%。对Ca(OH)₂絮凝出水进行臭氧氧化处理, 虽然降低了它的COD, 但并未进一步提高其NF膜通量, 其主要原因可能是臭氧氧化生成的硅氧烷类物质造成了膜的污染;与RO处理垃圾渗滤液生化出水相比较, NF膜无法分离废水中的酮类、胺和酰胺类、杂环类化合物, 使得NF产水的COD处在100~160 mg·L^-1。NF平均膜通量的增大可导致产水COD略有上升;垃圾渗滤液生化出水及其预处理水在NF处理过程中, 都没有表现出严重的膜污染。     

膜技术在垃圾渗滤液处理中的应用

介绍了微滤膜、超滤膜、纳滤膜和反渗透膜的基本性质,综述了膜技术在垃圾渗滤液处理中的应用和实际运行中膜污染问题与解决方法。     

预处理+厌氧+生化+膜深度处理垃圾焚烧厂渗滤液

以华北地区某一生活垃圾焚烧发电厂渗滤液项目为例，采用“预处理+厌氧+一级AO+UF+NF+RO”工艺处理，出水水质满足《城市污水再生利用工业用水水质》(GB/T 19923—2005)中敞开式循环冷却系统补充水标准后回用至冷却塔循环水。NF浓液采用物料膜减量化处理，RO浓液采用二级RO处理，最终浓液入炉回喷或至主厂区综合利用。经调试运行，本项目系统整体得率≥80%,COD、NH₃-N、TN去除率分别为99.97%、99.96%、99.90%，出水水质达标排放。     

垃圾渗滤液膜截留浓缩液处理工艺研究进展

膜生物反应器(MBR)、纳滤(NF)、反渗透(RO)组合膜法对垃圾渗滤液进行浓缩处理是目前垃圾渗滤液的主流处理工艺,文章主要对膜截留浓缩液的处理进行论述,总结了国内外相关的膜截留浓缩液处理工艺,根据现有工艺的优缺点、可操作性和实际生产中的应用状况对不同工艺进行了比较,指出高级氧化与生物处理组合工艺是浓缩液处理领域中一个重要的发展方向。     

微细通道内CO2沸腾换热与干涸特性

CO₂作为一种天然制冷剂在微通道内应用具有很大的换热优势,然而由于微尺度效应及其物性,在低干度区容易发生干涸,严重影响换热效果。为研究微细通道内CO₂流动沸腾换热与干涸特性,搭建了相应实验装置,对内径分别为1mm、2mm、3mm以及内表面粗糙度为16μm的不锈钢管,在CO₂制冷剂热流密度2~34kW/m²、质量流率50~1350kg/(m²·s)、饱和温度-10~15℃下进行换热性能与干涸实验对比研究。结果表明:常规管径换热特性在微细通道内不再适用;热流密度的增加对于强化核态沸腾换热具有显著影响,高于临界热流密度(critical heat flux,CHF)则发生干涸;质量流率对于核态沸腾区换热系数的影响则较小;不同饱和温度时换热特性有所不同,高饱和温度下换热系数随其升高而提高,低饱和温度下则相反;干涸过程对总换热系数的影响占34%。研究结论为CO₂微通道换热器的研究开发提供理论依据。     

An advanced treatment of high-strength opium alkaloid processing industry wastewaters with membrane technology: pretreatment, fouling and retention characteristics of membranes

This paper presents the results of the laboratory and pilot-scale membrane experiments of opium alkaloid processing industry effluents. Different types of ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) membranes were evaluated for membrane fouling, permeate flux and their suitability in separating COD, color and conductivity. Experiments demonstrated that membrane treatment is a very promising advanced treatment option for pollution control for opium alkaloid processing industry effluents. Almost complete color removal was achieved with NF and RO membranes. COD and conductivity removals were also greater than 95% and met the current local standards. Nevertheless, pretreatment was an important factor for the NF and RO membrane applications. Membrane fouling occurred with direct NF membrane applications without UF pretreatment. The total estimated cost of the UF and NF treatment system was calculated as $0.96/m³, excluding the concentrate disposal cost.     

Organic fouling of RO membranes: Investigating the correlation of RO and UF fouling resistances for predictive purposes

This study examines the characteristics of deposits from dead-end UF and cross-flow RO filtration of dilute mixtures of sodium alginate (SA) and humic acids (HA), which are representative of common foulants in RO and NF feed waters. The data are interpreted in terms of specific cake resistance, α. The presence of alginates in the mixed fouling layers, even in relatively small percentage, imparts characteristic properties to these deposits; i.e. a gel-like structure which is associated with reduced compressibility and permeability. With SA/HA mixtures, high rejection of organic species and high deposition factors are obtained in UF and RO tests, respectively. The specific resistance of mixed SA and HA deposits tends to increase with increasing SA concentration in solution. The resistances α exhibit fairly strong (power law) dependence on the pressure difference across the cake, ΔΡ_c, for both RO and UF tests. The fairly satisfactory correlation of resistance α versus ΔΡ_c data, obtained from both types of tests (for the mixtures of organic species tested at small salinity) is a significant result of this work. Based on this correlation, an approach is suggested for estimating fouling index I and initial membrane fouling rate of a specific RO process, relying on limited UF tests.     

组合膜-表面活性剂法处理垃圾渗滤液中的氨氮

氨氮是《生活垃圾填埋污染控制标准》(GB 16889-1997)严格控制的、也是传统工艺难处理的一项指标。文中以北京市北神树垃圾填埋场渗滤液为研究对象,采用组合膜-表面活性剂法对其氨氮进行了处理。水样依次通过OSMONICS微滤EW膜和超滤GE膜后,调节膜出水pH值为6.5,加入质量分数0.02%的十二烷基苯磺酸钠(SD-BS),通过静电引力与NH4+形成大分子的复合态铵,然后经反渗透SE膜进一步处理。处理后的水样清澈透明,无异味,水质达到了GB 16889-1997的一级排放标准,氨氮去除率为99.4%。另外还探讨了水样的pH值、SDBS投加量等因素对氨氮去除率的影响。     

膜技术在水处理中的应用与发展

膜技术方法很多，应用面也很广，本文对反渗透，电渗析，超过滤，纳滤和微孔过滤等膜技术在国内水处理方面的应用概况作一综合介绍。     

Landfill leachate treatment using hybrid coagulation-nanofiltration processes

In this study, treatment of landfill leachate using a novel electrocoagulation - nanofiltration (EC-NF) hybrid system was investigated. Leachate sample was collected from Whytes Gully landfill in Wollongong, Australia. The performance of electrocoagulation (EC) using aluminium electrodes as a pretreatment step for the nanofiltration process was compared against a conventional chemical coagulation (CC) process. Results reported here indicate that electrocoagulation is superior over the conventional coagulation process with respect to total organic carbon (TOC) and turbidity removal. At the optimum reaction time, TOC and turbidity removals by the electrocoagulation process were 67% and 80%, respectively. In comparison, at the optimum dosage of Al₂(SO₄)₃ obtained by a standard jar testing procedure, TOC and turbidity removals by the chemical coagulation process were only 10% and 65%, respectively. It is noteworthy that the amount of aluminium released by the electrocoagulation process to the solution was significantly higher than the optimum dosage of the chemical coagulation process. Therefore, better performance of the electrocoagulation process can possibly be explained by the higher coagulation concentration and the formation of polymeric aluminium which is known to be more effective for small organic compounds which are prevalent in landfill leachate. A remarkable difference between electrocoagulation and chemical coagulation pretreatment was also observed with respect to fouling mitigation in a subsequent nanofiltration process. For the two different nanofiltration membranes (NF 270 and SR2) used in this study, severe membrane fouling was evident when filtering raw landfill leachate or chemical coagulation pretreated landfill leachate. In contrast, fouling was not observed with an electrocoagulation pretreated feed solution. However, the use of electrocoagulation pretreatment did not result in any improvement in treated effluent quality by the hybrid system. Over all, there was no discernible variation between the EC - NF and CC - NF hybrid systems in their TOC and turbidity removals, which were approximately 92% and 99%, respectively. The reported results demonstrate that an EC - NF hybrid system can be a promising candidate for landfill leachate treatment, particularly for small and decentralised landfills where simplicity and robustness are required.     

膜技术在应用领域的进展

介绍了膜分离技术的工作原理以及膜材料的分类,综述了反渗透、微滤、超滤、纳滤、渗透蒸发及电渗析等几种常见膜技术的应用现状及进展情况.