震动膜超滤技术处理乳化液废水研究

考察了震动膜超滤处理技术对四种不同来源乳化液废水的效果和处理过程中膜通量变化,结果表明该技术对选用不同乳化液废水COD去除率在50.81%~95.25%,油类去除率在71.53%~98.96%,对SS能够100%截留,震动膜出水回收率为82%~85%,处理过程中,膜通量并没有随着运行时间的延长而降低,而是能够保持一定值甚至略有上升,表明震动膜超滤技术能够一定程度上改善膜污染现象,可用于乳化液废水处理预处理。     

乳化液废水处理技术的综述研究

介绍了乳化液废水的形成及特点,并对处理乳化液废水的化学混凝法、共凝聚气浮法、电凝聚法、高级氧化法、超滤法、生化组合工艺进行了综述,提出了乳化液废水处理的发展方向。     

产品与技术市场

WCH81—8型污水超滤处理设备技术参数超滤组件型号F_1×7;超滤膜总面积2.88m~2;操作压力<3kg/cm~2;适用温度0～40℃;适用酸碱度pH4～8;处理乳化液废水时,每班处理量500kg。     

浅谈超滤法处理钢铁企业冷轧厂乳化液废水

简述了超滤膜技术在冷轧厂含油及乳化液废水处理方面的典型应用.并详细论述了超滤膜工艺的特点、超滤膜材质、超滤膜配置、去除机理、超滤膜工艺的典型操作模式、超滤膜法处理含油废水及乳化液废水的优缺北点、以及其处理效果等.实践证明:采用超滤法处理冷轧厂含油废水及乳化液废水,能达到污水净化的目标.     

陶瓷膜处理轧钢乳化液废水操作条件优化及技术经济比较

陶瓷处理冷轧乳化液废水设备与国内进口的有机膜处理设备比较,二者处理效果基本相当,而进口有机膜设备价格约为国产陶瓷设备的４倍,进口有机膜处理设备的运行能耗为陶瓷膜的１０倍以上,正常的设备维修和药剂费用也大大高于国产陶瓷膜设备,加之考虑设备使用寿命,处理每吨冷轧乳化液废水的综合成本是国产陶瓷膜设备的６倍左右。因此,采用陶瓷膜处理冷轧乳化液废水在我国具有较大的技术经济优势。     

无机膜处理乳化废水中试研究

为除去废水中的乳化油,采用无机陶瓷微滤膜对乳化废水进行了中试实验研究.实验结果表明:乳化液废水经孔径为200 nm的无机陶瓷膜处理后,透过液可达国家排放标准;在最佳操作压力0.16 MPa下,系统可连续、稳定运行20 h以上,平均膜通量为272 L/(m2·h);化学清洗30 min后,可使膜通量恢复至初始通量的95%;平均料液运行成本为4.49元/m3.用无机陶瓷膜处理乳化液废水是一种经济、技术可行的方法.     

无机膜处理乳化废水实验研究

为除去废水中的乳化油,以达到环保排放标准,采用无机陶瓷微滤膜对乳化废水进行中试实验研究。实验表明:乳化液废水经孔径为200nm的无机陶瓷膜处理后,透过液可达国家排放标准;在最佳操作压力0.16MPa下,系统可连续、稳定运行20h以上,平均膜通量为272L.m-2.h-1;化学清洗30min后,可使膜通量恢复至初始通量的95%。经初步经济分析,平均单位(m3)料液运行成本为4.49元,实验结果表明,用无机陶瓷膜处理乳化液废水是一种经济、技术可行的方法。     

改进超滤技术处理废乳化液的试验研究

根据超滤技术在实际工程应用中所存在的问题,试验研究了废乳化液的pH、温度和超滤膜管的清洗方式对膜通量和衰减速度的影响规律,并优化了上述指标的操作参数.实际运行结果表明,原来存在的问题得到了很好的解决,工艺处理效果很好.     

超滤(UF)技术处理乳化油废水的研究

采用超滤工艺一间歇式错流操作模型一处理乳化油废水,选用了聚乙烯乙二醇超滤膜(PEG)和卷式膜组件,采用不同的超滤模型对超滤过程中超滤膜透水率、乳化油废水中的COD去除率的变化进行了实验研究,实验结果表明该模型对乳化油废水具有良好的处理效果。     

集成膜技术深度回用处理精对苯二甲酸废水研究

近两年来,膜法回用石化废水备受重视,利用集成膜技术对炼油和乙烯化工废水进行深度回用处理,目前已有相对成熟的经验,但集成膜技术用于精细化工产品精对苯二甲酸废水回用处理的研究尚少。在试验基本工况为超滤系统采用全量过滤方式,运行周期30min,内压式超滤运行通量不大于75L/(m2.h),超滤系统前加入絮凝剂PAC(投加量为5mg/L),低污染反渗透膜运行通量不大于19L/(m2.h),试验中系统回收率为70%,反渗透进水的COD含量小于40mg/L的条件下,精对苯二甲酸达标废水深度回用处理稳定运行,产水水质稳定可靠。     

膜生物反应器在水处理中的应用

膜生物反应器（MBR）是一种膜分离单元与生物处理单元相结合的新型水处理技术。由于膜生物反应器在污水处理中具有出水水质优异，操作运行简单，污泥产率低，占地面积小等特点，其应用范围和规模不断扩大。然而，膜污染和目前高昂的投资费用和膜污染是影响膜生物反应器进一步推广应用的主要因素。     

Integration of molecular dynamic simulation and free volume theory for modeling membrane VOC/gas separation

Gas membrane separation process is highly unpredictable due to interacting non-ideal factors, such as composition/pressure-dependent permeabilities and real gas behavior. Although molecular dynamic (MD) simulation can mimic those complex effects, it cannot precisely predict bulk properties due to scale limitations of calculation algorithm. This work proposes a method for modeling a membrane separation process for volatile organic compounds by combining the MD simulation with the free volume theory. This method can avoid the scale-up problems of the MD method and accurately simulate the performance of membranes. Small scale MD simulation and pure gas permeation data are employed to correlate pressure-irrelevant parameters for the free volume theory; by this approach, the microscopic effects can be directly linked to bulk properties (non-ideal permeability), instead of being fitted by a statistical approach. A lab-scale hollow fiber membrane module was prepared for the model validation and evaluation. The comparison of model predictions with experimental results shows that the deviations of product purity are reduced from 10% to less than 1%, and the deviations of the permeate and residue flow rates are significantly reduced from 40% to 4%, indicating the reliability of the model. The proposed method provides an efficient tool for process engineering to simulate the membrane recovery process.

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炼油净化水结垢原因分析及膜法深度处理

对炼油厂净化水回用过程结垢原因进行分析,针对结垢成因采用陶瓷膜对净化水做深度处理,而经膜处理后净化水pH在6.9左右,净化水呈中性,试图使得炼油净化水达到工艺水回用目的.着重考察了膜孔径、操作压差、膜面流速、料液温度等对膜通量的影响.结果表明,孔径为50nm的氧化锆陶瓷膜处理炼油净化水其渗透通量高达800L·m~2·h~(-1),渗透液中COD小于200mg·L~(-1);体系的操作压差可控制在0.25MPa,较大的膜面流速大和料液温度有利于渗透通量的提高;膜污染的清洗采用在线反冲和离线化学清洗的方法,料液渗透通量可恢复到新膜的95%.     

Membrane autopsy to investigate CaCO3 scale formation in pilot‐scale,submerged membrane bioreactor treating calcium‐rich wastewater

BACKGROUND: Membrane scaling is an area of research interest because it can deteriorate membrane performance. The extent to which membrane scaling is produced varies depending upon the concentration of scale‐forming species such as calcium on the membrane surface. Bench‐scale tests have been conducted to better understand membrane scaling in submerged membrane reactors (MBR). However, relatively few studies of membrane scaling in pilot‐scale, submerged MBR have been reported. The objective of this study was to perform membrane autopsy work to analyze membrane scaling in a submerged MBR treating calcium‐rich wastewater. RESULTS: Membrane autopsy work provided evidence that deposition of calcium carbonate (CaCO₃) scale occurred on the membrane surface at the completion of pilot‐scale, submerged MBR operation. The CaCO₃ scaling resulted in significant external fouling on the surface of the membrane. The membrane scaling increased the rejection of calcium with MF membranes. However, the level of CaCO₃ scaling as internal fouling (in the pores) was almost negligible. This autopsy work also showed that aeration did not play a major role in controlling CaCO₃ scaling at the membrane surface in a submerged MBR. Chemical cleaning using citric acid solution efficiently removed CaCO₃ scale from the membrane. Combining citric acid with sodium hypochlorite pretreatment provided synergistic effects, further reducing CaCO₃ scale formation. CONCLUSION: The carbonate salt of calcium leads to precipitation resulting in surface fouling of membranes, and this cannot be removed physically by aeration in a submerged MBR treating calcium‐rich wastewater. It is necessary to combine properly‐selected cleaning strategies with submerged MBR treating wastewater containing a high potential for inorganic chemical precipitates. Copyright © 2009 Society of Chemical Industry     

Development of a generic process model for membrane adsorption

In this work, a generic model describing the dynamic adsorption behaviour of proteins on membrane adsorbers over complete purification cycles under consideration of module geometry and of the interaction between multiple transport mechanisms is developed.A general rate model for membrane adsorption, in which the interaction between multiple phenomena, like mass transfer and adsorption kinetics are considered, is formulated. Hereby, the implemented isotherms describe the influence of eluting agents on the adsorption behaviour, so that complete purification cycle (loading, washing and elution operation) can be simulated.Using the developed model the theoretical influence of relevant transport phenomena, operating conditions and process scale on affinity and ion exchange membrane adsorption of proteins are investigated. An example on ion exchange membrane adsorption illustrates the possibility to predict scale up effects occurring in configurations of multiple membrane adsorber modules. The obtained simulation results are in accordance with experimental observations reported in literature.     

缺氧-好氧-膜生物反应器处理人粪尿工艺研究

研究采用处理规模为4L/d的缺氧-好氧-膜生物反应器组合工艺处理人粪尿。试验运行稳定,技术可行,在硝化段水力停留时间为90d,DO的质量浓度为1.8～3.0mg/L,pH值为7.5～8.0;反硝化段DO的质量浓度不大于0.4mg/L,pH值为7.0～7.5的条件下,对CODCr,氨氮,总无机氮的平均去除率分别保持在97%,98%和97%以上,明显高于二级生化工艺。同时利用稳态数据与动力学方程,对,YKd,vmax,KS4个动力学参数进行了求解。     

超滤膜和微滤膜在污(废)水处理中的应用研究现状及发展趋势

超滤膜和微滤膜的应用范围和规模正在逐年扩大,作者引用了29篇文献,概述了超滤膜和微滤膜在污（废）水处理领域的应用研究现状及其发展趋势。     

循环水排污水中残余阻垢剂对反渗透膜性能的影响

循环水排污水中残余的阻垢剂会导致其水质的变化,从而影响反渗透膜性能。本文以循环水中常用的阻垢剂聚天冬氨酸(PASP)、羟基亚乙基=膦酸(HEDP)和氨基三亚甲基膦酸(ATMP)为研究对象,首先考察了它们的阻垢性能,然后在此基础上,通过静态浸泡试验和动态试验考察了它们的存在对反渗透膜性能的影响。研究结果表明,PASP、HEDP和ATMP中,PASP的阻垢性能最优,阻垢率高达84.21%,三者均会对反渗透膜的表面结构、组成成分、膜通量以及脱盐率产生一定的影响。当PASP、HEDP和ATMP的浓度分别为50mg/L、10mg/L和30mg/L时,在反渗透系统连续运行10h后,膜通量分别下降5.53%、4.89%和9.09%,小于空白时的18.95%;此外,脱盐率有不同程度的提高。     

膜生物反应器（MBR）系统动力学研究

上层清液和整个MBR系统动力学研究表明：MBR系统中上层清液COD降解速度对COD浓度为一级反应,建立经验速度方程：rCOD=-dCCOD／dt=0,473CCOD（mg／L·h）;整个系统COD降解速度对COD浓度为零级反应,建立经验速度方程：rCOD：1.877（mg／L·h）。     

Modeling scale formation in flat‐sheet membrane modules during water desalination

Modeling the operation of spiral‐wound membrane modules is essential for their successful design and optimization. Such models must include the main types of membrane fouling, degrading desalination plant performance, including scaling due to sparingly soluble salts. Unfortunately, the complexity of underlying physicochemical processes and the coexistence of several spatial and temporal scales render intractable modeling of membrane scaling based on first principles. Therefore, a suitable (albeit simplified) framework is developed for incorporating scaling dynamics into a fluid flow model formulated at an intermediate (i.e., mesoscopic) length scale of membrane operation. The general mesoscopic approach involves integration of spatially distributed submodels, thereby allowing predictions at the large (entire membrane sheet) scale; these submodels comprise constitutive laws and kinetic rate expressions derived at fine scales. A submodel for the effect of pre‐existing bulk particles on scale formation is developed herein. Several numerical results are presented to exemplify the potential of the proposed framework. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2917–2927, 2013