反渗透、超过滤过程中的浓差极化

浓差极化是反渗透、超过滤过程中的重要影响因素.为了合理进行装置设计,较准确地确定湍流状态下的浓差极化,作者通过推理分析和归纳,求得浓差极化比的计算公式.与前人工作的初步对比,本文公式具有一定的代表性,可用于较宽的F_w范围,特别是在较高的F_w下,能较好地反映真实规律.这对预估反渗透膜分离过程中的浓差极化有较大的参考价值.     

超滤及反渗透系统化学清洗方案

超滤和反渗透系统是电厂水处理设备中的重要组成部分。阐述了电厂化学水处理系统的污染来源及判定方法,探讨了超滤系统和反渗透系统化学用水处理过程中尘垢和污染物的清洗方法,主要利用酸性或碱性药剂的化学性质达到清理设备内部污垢的目的,为相关工作人员提供理论的参考依据。     

反渗透膜与超滤膜的过滤性能分析

以反渗透膜与超滤膜为研究对象,通过计算跨膜压差、膜通量、渗透系数,对这两种滤膜的过滤性能进行比较分析。     

超滤膜和反渗透膜联用处理苦咸水

介绍了将超滤膜和反渗透膜联用的水处理工艺,并对此种方法进行了研究。结果表明,在原水为苦咸水、含盐量在4010～4500mg／L的情况下,经预处理超滤膜和反渗透膜联用的水处理工艺对CODMn、总硬度、Cl^-的去除率分别达到了95％、98％、97％以上,脱盐率也达到97％以上,连续运行稳定,出水水质优于中华人民共和国饮用水标准。在实验基础上研究并探讨了超滤膜和反渗透膜联用的水处理工艺特性,为其在中水回用和小型饮用水装置等水处理应用提供实验依据。     

A General Diagram for Estimating Pore Size of Ultrafiltration and Reverse Osmosis Membranes

Abstract

A slit sieve model has been used to develop a general correlation between the average pore size of the upstream surface of a membrane and the molecular weight of the solute which it retains by better than 80%. The pore size is determined by means of the correlation using the high retention data from an ultrafiltration (UF) or a reverse osmosis (RO) experiment. The pore population density can also be calculated from the flux data via appropriate equations.     

超滤和反渗透联用处理玉米浸渍水

对玉米浸渍水的膜分离过程进行了研究，开发出超滤和反渗透联用的分离方法。反渗透浓缩液中蛋白质的截留率为99．77％，反渗透透过液中COD值降到1000左右，可用作工艺回用水，反渗透浓缩液中可提取乳酸等有用物质，超滤浓缩液可浓缩成玉米浆。     

反渗透水处理技术的应用

介绍了反渗透水处理技术的原理和作用,并与电渗析法水处理技术进行比较.详细介绍了该技术在地下水处理应用中的工艺、设备和常见故障处理.采用反渗透水处理技术后,原水利用率提高,原水用量减少35 m3/h,年减少地下水开采量26万m3,外排水减少20万m3;系统水质提高,变换催化剂使用寿命延长至3年以上,吹风气余热回收系统蒸汽...     

Electrodialysis Application of the Ultrafiltration Permeate of Milk Before and After Reverse Osmosis

Ultrafiltered (UF) milk permeate was concentrated by reverse osmosis (RO). UF and UF + RO samples were then desalted by electrodialysis (ED) to three levels of desalination: 1, 2.5, and 4 % of ash in the dry matter. Ions were analyzed by a new high‐performance liquid chromatography method, which enables simultaneous estimation of cations and anions. ED of UF permeate has some advantages over that of UF + RO samples, including a shorter ED time and a higher average salt flow rate, but RO treatment of UF permeate before ED enables the processing of larger volumes of UF permeate. Therefore, ED of milk permeate, particularly after RO, improves the handling characteristics and may offer advantages for further processing of secondary dairy products.     

超滤／反渗透及其组合工艺在废水处理中的应用进展

简要介绍了常规超滤、反渗透膜技术的基本原理,详细综述了膜技术在废水处理领域的应用现状及其动态,在此基础上,科学展望了超滤／反渗透组合工艺在厌氧发酵废水处理行业的应用前景。     

双膜技术在油田污水中的中试试验研究

针对注汽锅炉用水水质要求,采用超滤+反渗透双膜技术对河南油田王集转油站污水处理系统"两级沉降+两级过滤"处理后的污水进行深度处理,通过一个多月的中试连续试运行,结果表明经过双膜技术处理后的污水各项指标均满足进锅炉水质标准。     

反渗透膜的清洗

文章介绍了反渗透装置在处理氯化铵废水过程中遇到的膜污染问朋和化学清洗方法的确定,以及清洗后取得良好的效果.     

Borosilicate Microporous Glasses for Reverse Osmosis

The characteristics of microporous borosilicate glasses are described. Glasses with an optimum pore distribution are recommended for production and application.     

Impact of Protein Removal by an Upstream Ultrafiltration on the Reverse Osmosis of Skim Milk and Sweet Whey

Concentration of milk and whey by ultrafiltration and reverse osmosis (RO) in cascade mode is an amendment of evaporation for high volume reduction ratios (VRR) prior to drying. This study investigated the impact of a prior protein removal and the transmembrane pressure (TMP) on the RO stage, compared to skim milk and sweet whey. It could be found that removal of the protein fraction of both skim milk and sweet whey improved the efficiency of the RO. An upstream ultrafiltration resulted in higher VRR as well as an increased permeate flux.     

反渗透膜的污染及清洗

文章论述了反渗透膜在水处理中常见的污染现象以及反渗透膜元件污染的判断处理。根据污染的类型、程度、膜材料的性能选择清洗剂,设计出合理的清洗方案,快速恢复反渗透膜的膜通量。     

反渗透系统的污染及清洗

反渗透作为水处理领域的一种高新除盐技术应用日益广泛。如何防止膜元件的污染及污染后的清洗是当前反渗透技术应用中的一个难点。本文结合长铝公司 40 0m3 /h反渗透系统的运行和清洗经验 ,就该问题进行一些探讨     

镀镍漂洗水反渗透浓缩液的使用

利用反渗透技术将镀镍漂洗水浓缩分离,浓缩液补加到镀镍槽中,透过液在镀镍漂洗槽中循环使用。向镀镍槽中加入硫酸钾,提高镀液的导电性能,同时降低镀液中氯化镍的浓度,使镀镍过程中阳极溶解速度和阴极沉积速度相等。镀件在镀镍前和镀镍后都经过回收槽漂洗,使回收槽中镍离子的浓度保持不变。用过硫酸钠氧化和活性炭吸附浓缩液中的有机杂质,用氢氧化钾沉淀铁杂质,用电解法处理铜杂质,用电解法和锌抑制剂组合法处理锌杂质。采用这些措施后,可实现反渗透浓缩液的完全回收利用。     

Aromatic Polyamide Hydrazide Membranes for Reverse Osmosis Separations

Abstract

Wholly aromatic polyamide hydrazide (PAH) polymers were synthesized by low temperature polycondensation from freshly prepared m-amino benzhydrazide, p-amino benzhydrazide, isophthaloyl chloride, and terephthaloyl chlorides in dimethyl acetamide solvent. A series of film-forming polymers prepared by altering the molar ratios of the reacting monomers was characterized in terms of % moisture regain, η_inh, and x-rays. Asymmetric membranes prepared from selected polymer samples were tested in reverse osmosis test cells, and the pure water permeability and the membrane constant were determined. An optimum meta: para molar ratio of the reacting monomers has been identified for the best performance under reverse osmosis which gave solute separation close to 98% for a feed concentration in the range of seawater. The PAH membranes appear to be potential barrier candidates for treatment of effluents containing ammonium, nitrates, etc. and radioisotopes. Separation data for a few other solute systems were also evaluated and compared with those obtained from cellulose acetate membranes.     

尿素工艺冷凝液的膜处理研究

川化股份有限公司三胺装置与二化尿素装置联产后,二化尿素工艺冷凝液电导升幅较大,不能有效地回收利用.本文进行了反渗透膜法处理三胺与尿素装置联产的工艺冷凝液的试验,研究了工艺冷凝液主要组分处理前后的变化.     

反渗透预处理系统问题的分析与措施

反渗透给水的预处理一般包括源水到反渗透给水泵之前的一切处理[1].良好的预处理是反渗透装置长期稳定运行的必要条件.通过对上海焦化有限公司除盐水二组反渗透及其预处理系统在开车初期污染频繁、保安过滤器滤芯寿命过短等异常情况进行分析,提出相应的预处理系统改进方案,实施后,消除和减少了给水污染,为反渗透系统的可靠运行打下良好基...     

海水反渗透膜处理含硼废液的性能研究

在小型反渗透装置上运用某进口海水反渗透膜元件对模拟含硼放射性废液中硼酸进行分离实验,考察了不同压力、温度、pH条件下反渗透对硼酸的截留性能。结果表明:在4 MPa和5 MPa的工作压力下,即使含硼废液为中性(pH为7左右),该反渗透装置也能达到93%以上的硼截留效率,相比普通反渗透膜在中性条件下硼截留效率仅为40%~80%,有较大提升,在核电站含硼废液处理问题上具有一定的工程应用前景。