连续操作超滤过程最优膜面积的确定

推导了在连续操作条件下超滤过程膜面积的确定方法,并以红霉素滤液为对象进行说明,连续操作时膜面积的最优安排呈代表团的树状结构;级数越多,所需的膜总面积越少,但综合权衡操作有数以４级为宜,各级浓缩比相等时不是最优配置方法,其最优值须通过计算得出,总浓缩比对膜面积的影响很大。连续操作时所需膜总面积比相同条件下分批操作时为大,即其平均通量比分批操作时小。     

中空纤维膜在阳极电泳漆超滤系统中的应用

本报道了荷负电中空纤维膜用于阳极电泳漆超滤系统的试验结果。结果表明，此荷负电中空纤维膜具有优良的抗污染性能；透水率高；能满足阳极电泳漆超滤系统要求；有可能取代醋酸纤维素管式膜而应用于阳极电泳漆超滤系统。     

含酚酞侧基聚芳醚酮中空纤维超滤膜处理含油脱脂液

本文报道了含酚酞侧基聚芳醚酮中空纤维膜用于含油脱脂液的处理。结果表明：此超滤膜能有效地去除脱脂液中油份使之低于１．０ｍｇ／Ｌ，膜的透水率比较大，约为５×１０－４ｍ３／ｍ２·ｋＰａ。有可能应用于金属表面涂装行业而实现脱脂液处理的闭路循环。另外，对膜的超滤性能也进行了研究     

鼓泡超滤法用于木糖生产过程的探讨

目前工业中以玉米芯为原料,经过水解、中和、二次脱色和二次离子树脂交换等步骤,制取木糖,但操作复杂,成本较高.本试验将膜超滤技术引入到木糖生产工艺中,研究了压力、流量和温度等因素对超滤的影响,超滤能很好地截留杂质,提高木糖纯度.浓差极化和膜污染是超滤过程中最常见的两个主要障碍,使用鼓泡法来改善浓差极化和膜污染对膜性能的影响.大量试验表明,超滤能代替一次脱色处理并能优化其它工艺操作,可应用于木糖生产.     

用于膜蒸馏的中空纤维膜组件优化

引　言膜蒸馏是一项新型膜分离技术 ,具有常压低温操作、可利用废热等优点 ,受到越来越多研究者的重视[1] .可用于膜蒸馏的组件有多种 .从商业角度考虑 ,中空纤维膜及管式膜更具吸引力 ,因其单位体积设备可得到较大的膜面积 ,且能减轻极化现象的影响 .许多膜蒸馏研究工作中采用了中空纤维膜组件 ,Ａｇａｓｈｉｃｈｅｖ等求解了层流状态下的传热方程[2 ] ,Ｈｏｇａｎ等人将膜蒸馏与太阳能装置耦合 ,并通过换热系统回收部分热量 ,有效地提高了热效率[3] .但目前尚没有针对膜蒸馏设计的膜组件 ,膜蒸馏通常采用微滤膜组件 .而由于传热现象的影响…     

胶束强化超滤脱除氯苯及其膜污染的研究

以十六烷基氯化吡啶 (CPC)作为表面活性剂 ,利用聚醚酰亚胺 (PEI)中空纤维超滤膜 ,对含氯苯废水进行了胶束强化超滤 (MEUF)研究 ,讨论了 CPC浓度对氯苯脱除的影响 ,以及料液流速、操作压力和操作时间对膜污染的影响。在 CPC浓度 (Cf)为 3 .1 g/L～ 1 8.6 g/L的范围内 ,氯苯浓度为 0 .45 g/L时 ,CPC的截留率可大于 95 % ,而氯苯的脱除率可达 98.0 %以上 ,渗透通量可达 1 .0× 1 0 -10 m3/m2·s·Pa。采用去离子水对膜清洗 1 h后 ,膜纯水通量恢复率可达 95 %。     

电泳漆超滤中空纤维膜的性能研究

本文报道了ＭＴＣＡ型中空纤维超滤膜的双电性及用于电泳漆的超滤性能。结果表明此膜对国内外各种类型的电泳漆有较强的适应性，并且具备较好的抗污染性。长时间试验表明ＭＴＣＡ型中空纤维超滤膜及其组件用于电泳漆超滤性能稳定。     

中空纤维膜的研究现状与发展

本文综述了中空纤维膜近年来国内外在反渗透、超滤、微滤及气体分离方面的开发应用现状。重点介绍了在渗透汽化、膜萃取、膜蒸馏等过程中的最新研究状况，并提出了对发展中空纤维膜的几点看法。     

中空纤维膜组件反冲操作的渗透特性

研究了中空纤维膜组件在反冲操作时膜管内压降规律,考察了膜渗透系数、膜长度及膜内径对膜内压力分布及透量因子的影响。确定了在一定长度的膜组件中存在着膜的最佳直径,在最佳直径下,膜组件的渗透流量最大。     

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。     

Integration of Ultrafiltration Unit Operations in Biotechnology Process Design

A stepwise process design approach is proposed to model membrane unit operations generally in combination with experimental model parameter determination in laboratory scale, in order to predict the purification performance a priori by simulations for multicomponent mixtures. The development of a rigorous model for an ultrafiltration membrane is described. In conceptual process design, the degree of comprehension of all unit operations integrated have to be almost identical to be able of any consistent process proposal taking equipment‐related fluid‐dynamical and kinetic nonidealities besides thermodynamical feasibility into account. Therefore, a process model, combining the most limiting factors within one mathematical model, is established and various filtrations are carried out with a binary solution for validation. Additionally, a standard laboratory equipment is instituted for logging time‐dependent concentration profiles. The practicability of the proposed procedure is proven in order to design and integrate ultrafiltration membranes into total purification processes.     

活性炭UF膜分离污水中COD的实验研究

试验考察了粉末活性炭的投加对超滤膜运行性能的影响,结果表明:随粉末活性炭投量的增加膜稳定运行时间延长,通量下降率降低。粉末活性炭的投加对膜过滤阻力影响不大。在此基础上又对PAC-UF组合系统去除有机物的效果进行了进一步研究,主要是对比研究了不同PAC投加量对5种不同配置水样中有机物的去除效果。得出如下结论:在相同PAC投加量下,CODMn值大的水样的CODMn平均去除率高,且出水CODMn值相近。说明了PAC-UF组合系统出水稳定,受水质差异的影响不大。     

L‐Lysine Monohydrochloride Syrup Concentration using a Membrane Hybrid Process of Ultrafiltration and Vacuum Membrane Distillation

The development of energy saving membrane separation processes is finding a unique position in process industries. One of the important areas where they are employed is the biotechnology industry. This industry has its own specifications and requirements, e.g., levels of diluteness, thermal, chemical and shear fragility. Membrane separation processes have the characteristics necessary to match these specifications and needs. In this research, the determination of the experimental concentration of L‐Lysine monohydrochloride (L‐lysine‐HCl) syrup was investigated using ultrafiltration (UF) and vacuum membrane distillation (VMD) hybrid membrane processes. Four parameters that are known to have significant influence on the UF process were examined, i.e., pressure difference across the membrane, feed concentration of L‐lysine‐HCl, feed velocity on the membrane surface, and pH. For the VMD unit, pressure difference and pH were replaced with feed temperature and vacuum pressure on the permeate side of membrane. Each process was carried out separately and the results were used to design a bench‐scale process. In order to save time and money, the Taguchi method of experimental design was employed. The effects of feed concentration, pressure difference across the membrane, feed velocity on the membrane surface, and pH on the target variable, i.e., the membrane flux, in the UF process were 39.93, 38.65, 9.36, and 9.59 %, respectively. For the VMD process, these values were 64.79, 22.16, 6.21, and 2.14 % for feed temperature, feed concentration, vacuum pressure on the permeate side, and feed velocity on the membrane surface, respectively.     

Application of Statistical Design to an Industrial‐Scale Dead‐End Ultrafiltration Process

An industrial‐scale dead‐end ultrafiltration system was optimized using statistically designed experiments. Given a certain level of pollutant, a two‐level full factorial design and a central composite design were used to optimize the filtrate production of a single 8‐inch industrial ultrafiltration membrane while manipulating the levels of four factors: feed pressure, backwash pressure, forward filtration time, and backwash time. Analysis of variance and residual analysis were used to validate and check the adequacy of the developed regression models. The optimal levels were later validated experimentally. The predicted filtrate production was in reasonable agreement with the experimental data.     

超滤膜在水处理中的应用

主要针对目前超滤膜技术在水处理中的广泛应用研究进展,分别从市政府给水、纺织印染废水、造纸废水、制革废水、电镀废水、食品废水、屠宰废水等方面介绍了国外超滤膜技术应用的动态和前沿;并指出目前超滤膜在水处理中应用存在的问题和今后研究的方向。     

Ultrafiltration recovery of alginate: Membrane fouling mitigation by multivalent metal ions and properties of recycled materials

Recovery of alginate extracted from aerobic granular sludge (AGS) has given rise to a novel research direction. However, these extracted alginate solutions have a water content of nearly 100%. Alternately, ultrafiltration (UF) is generally used for concentration of polymers. Furthermore, the introduction of multivalent metal ions into alginate may provide a promising method for the development of novel nanomaterials. In this study, membrane fouling mitigation by multivalent metal ions, both individually and in combination, and properties of recycled materials were investigated for UF recovery of sodium alginate (SA). The filtration resistance showed a significantly negative correlation with the concentration of metal ions, arranged in the order of Mg²⁺ < Ca²⁺ < Fe³⁺ < Al³⁺ (filtration resistance mitigation), and the moisture content of recycled filter cake showed a marked decrease. For Ca²⁺, Mg²⁺, Fe³⁺, and Ca²⁺+ Fe³⁺, the filtration resistances were almost the same when the total charge concentration was less than 5 mmol⋅L^–1. However, when the total charge concentration was greater than 5 mmol⋅L^–1, membrane fouling mitigation increased significantly in the presence of Ca²⁺ or Fe³⁺ and remained constant for Mg²⁺ with the increase of total charge concentration. The filtration resistance mitigation was arranged in the order of Fe³⁺ > Fe³⁺ + Ca²⁺ > Ca²⁺ > Mg²⁺. Three mechanisms were proposed in the presence of Fe³⁺, such as the decrease of SA concentration, change in pH, and production of hydroxide iron colloids from hydrolysis. The properties of recycled materials (filter cake) were investigated via optical microscope observation, dynamic light scattering, Fourier transform infrared, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy. The results provide further insight into UF recoveries of alginate extracted from AGS.     

间歇精馏脉动馏出方式的研究

对间歇精馏脉动操作在产品馏出段的产品进行了研究,通过实验证可知,所建立的数学 可以较好地描述该操作过程各参数的变化规律。提出了一种以过程分离因子为基础的目标函数,可方便地用于衡量二元间歇精馏不同操作策略产品馏出段的分离效果。