钛金属膜过滤油田污水的污染阻力研究

以阻力系列模型为基础,考察了钛金属膜过滤油田污水时膜结构和操作条件等因素对污染阻力的影响。结果表明:滤饼层阻力是主要阻力,膜孔堵塞阻力为第二关键阻力。膜孔径增大,滤饼层阻力降低,膜孔堵塞阻力增加,且二者均随压力增加而增大;随着膜面流速的增加,滤饼层阻力降低,膜孔堵塞阻力增大;在过滤操作的前15～20min,污染阻力增长迅速。实验所得结论将为确定最佳工艺条件和膜清洗方法提供可参考的依据。     

工业废水电渗析过程中膜污染研究进展

综述了工业废水电渗析体系膜污染类型、性质、影响因素等的研究进展. 无机污染主要是Ca2+, Mg2+或其他高价离子在离子膜表面或内部形成的结垢现象,原理是极化或溶液过饱和形成沉淀. 有机污染是由蛋白、腐植酸、表面活性剂及大分子有机物在离子膜表面沉积或渗透到膜内部而形成,原因主要是带负电荷的有机物与阴膜荷正电基团的静电作用及带苯环有机物与基膜的亲和作用,其次是有机物分子大小与膜的网络结构的作用. 膜污染形成及其性质与施加电流、共存组分、温度、pH值和运行时间等密切相关,可造成离子膜导电性、离子交换容量、水含量和极限电流密度等减小,且有机污染对电渗析性能的影响比无机污染更严重. 由有机物凝胶层形成的膜污染可用电渗析膜污染指数定量描述.     

膜生物反应器中膜污染机理的研究

在采用膜生物反应器（MBR）处理染料废水的过程中,通过对活性污泥进行终端过滤来反映膜污染机理,着重考察了膜过滤的形式、膜通量变化和膜污染的形成。污泥的终端过滤过程严格符合沉积过滤定律;膜通量随过滤时间呈指数衰减趋势,并在几分钟内就达到相对稳定值;扫描电镜照片也证实了膜污染主要是膜面沉积层引起的。     

膜生物反应器在高氨氮废水处理中的应用

膜生物反应器作为一种新兴的污水处理技术与工艺,其研究与应用受到了社会各界的广泛关注。文章综述了高氨氮废水的特点、危害,简要介绍了膜生物反应器的特点及各国学者将其应用在废水处理中的研究成果,指出了膜生物反应器的不足和应对策略,展望了未来膜生物反应技术在我国的发展前景。     

膜技术在油田采出水处理中的应用研究

采用无机陶瓷膜处理设备处理宝浪油田采出水,研究结果表明:处理后的采出水完全能满足宝浪油田注水的水质要求。产出水中的悬浮物含量小于1mg/L。0.1μm膜处理后的采出水中悬浮物含量平均值为0.417mg/L,粒径中值小于1μm;0.2μm膜处理后的采出水中悬浮物含量平均值为0.57mg/L,粒径中值小于1.5μm;产出水中油含量低于检测限;膜清洗周期为85个小时;清洗方法简单;膜通量的恢复率为99.93%。     

Treatment of Oily Wastewaters Using the Microfiltration Process: Effect of Operating Parameters and Membrane Fouling Study

This work focuses on the treatment of oily wastewater using the cross-flow microfiltration (MF) process to determine the effect of different operating parameters such as transmembrane pressure (TMP) and cross-flow velocity on the separation performance and to study the mechanism of membrane fouling during microfiltration of oil in water emulsions. In this regard, the permeation flux and oil rejection of a polyvinylidene fluoride (PVDF) membrane in a flat-frame MF module for separation of 3000 ppm oil/water emulsions were measured. The results indicated that the permeate flux increased by an enhancement in both TMP and cross-flow velocity, while the oil rejection decreased. The analysis of variance (ANOVA) showed that the individual effect of TMP and cross-flow velocity is more important than the interactional effect of these operating parameters on the permeate flux and oil rejection. The results of fouling modeling revealed that the membrane fouling mechanism was affected by the applied TMP. The cake filtration model dominates the fouling mechanism at lower operating pressures. The fouling mechanism was changed from the cake formation to intermediate pore blocking and then to standard pore blocking as the TMP varied from 1 to 3 bar. Finally, a five-step procedure was used for cleaning the oil/water fouled membranes.     

水处理中超滤膜污染及其应对方式研究进展

对超滤膜污染以及缓解膜污染的主要方法进行了综述,介绍了污染原因、主要污染物质、污染类型,叙述了膜前预处理、膜清洗、膜改性等当下为应对膜污染所采用的主要方法和紫外、外加磁场、电场等膜污染控制新方法,总结了从源头上控制膜污染的探索方向,认为超滤技术要在运行方式和工艺设计上做出更合适的选择,未来将向着低能耗、低药耗、自动化和...     

膜生物反应器污泥混合液对膜污染影响研究进展

膜生物反应器(membrane bioreactor,MBR)作为一种高效的污水处理及回用工艺,近年来备受关注,然而MBR的膜污染问题严重制约了该工艺进一步快速的商业化推广.本文综述了污泥混合液各组分对MBR膜分离的影响,包括溶解性微生物代谢产物(soluble microbial product,SMP)、胞外聚合物(extracellular polymeric substances,EPS)、污泥浓度(mixed liquor suspended solids,MLSS)、颗粒粒径及无机物对膜污染影响,并对该领域未来的研究方向进行了论述.     

Membrane Characteristics and Fouling Study in MEUF for the Removal of Chromate Anions from Aqueous Streams

Abstract

Micellar‐Enhanced Ultrafiltration (MEUF) of the chromate anions from aqueous solutions has been studied at room temperature (28±2°C) using cationic surfactants, cetyltrimethylammonium bromide (CTAB), and cetylpyridinium chloride (CPC), micelles of which adsorb the chromate ions by electrostatic interactions. The solution is processed by ultrafiltration, using a membrane with a pore size small enough to block the passage of the micelles and the adsorbed ions. The process is highly efficient in removing the chromate ions. In the absence of other electrolytes, chromate ion rejections up to 99% were observed at optimal conditions of pH, pressure, temperature, feed chromate, and surfactant concentrations. The presence of added NaCl reduces the chromate rejection, but it was still considerable (up to 82%), even in the presence of 100 mM NaCl. The rejection rate of chromate was found to be highly dependent on the pH of the feed solution. The influence of membrane characteristics on the chromate ion removal was also studied. Various resistances like fouling resistance, concentration polarization resistance, and membrane resistance were also estimated to quantify their effects on the removal efficiency and on the flux behavior.     

新型硅橡胶膜生物反应器用于有机废水处理的膜传质动力学

用中空纤维型硅橡胶管构造了管束式和卷绕式两种膜器,将它们结合进一个生物反应器系统,用于对废水中的挥发性有机化合物（VOC）进行生物降解处理。本文以甲苯为对象,研究了VOC在这种系统中穿过膜的传质问题。基于液-膜-液的串联阻力概念和质量平衡,构造了一个关于膜总传质系数的简单指数模型,用于传质实验的分析。将甲苯溶于水中模拟有机废水,配制适合于甲苯降解细菌生长的培养液,进行了甲苯从废水穿过膜到培养液中的传质实验,并将细菌移植进培养液进行了生物降解条件下的传质实验。对培养液中细菌存在和不存在两种情况下的甲苯传质实验进行了分析。结果表明,总传质系数的指数模型基本上与实验条件符合,所得到的甲苯的总膜传质系数具有10-6m·s-1数量级,卷绕膜器的总传质系数较管束型的稍高,生物反应条件下的总传质系数又较细菌不存在时的稍高。     

膜分离在生物工程应用中的问题及解决方法

分析了膜分离在生物工程应用中存在的问题和解决上述问题的方法。     

陶瓷微滤膜处理钛白生产废水研究

对陶瓷微滤膜处理钛白生产废水过程中工艺参数对膜性能的影响进行考察,获得了适宜的工艺条件：膜孔径为１．０μｍ,操作压力在０．２０ＭＰａ左右,错流速率２～５ｍ／ｓ、操作温度视工厂余热情况确定,适于在２０～５０℃,浓缩可以在膜通量维持基本不变的情况下在一定浓度范围内进行,同时确定了选择合适的操作压力的简便方法,起到了节省实验材料和时间的作用。