Diafiltration and water recovery of Reactive Brilliant Blue KN-R solution by two-stage membrane separation process

The conventional process of Reactive Brilliant Blue KN-R production is low purity, labor intensive, inconsistent in the production quality and also causes pollution. The improved process based on membrane technology still generates large volume of effluent though with low pollutants. In this paper, a two-stage membrane separation process is introduced to resolve these shortcomings, in which the first stage is used for diafiltration and concentration of dye solution, and the second is to recover the dye and salt water from the produced permeate. Comparing results from one ultrafiltration (UF) membrane (GH) and four nanofiltration (NF) membranes (AFC40, DL, CA865 and MPT-31), UF membrane ES404 showed the same dye rejection, higher permeate flux and lower sodium sulfate rejection. In the diafiltration and concentration stage, pre-concentration and constant volume diafiltration had the best salt permeability as compared to constant volume diafiltration and post-concentration in addition to variable volume diafiltration. In the dye and salt water recovery, membrane ES404 had the same dye rejection, but higher permeate flux and lower sodium sulfate rejection as compared to membrane GH. The proposed two-stage membrane separation process offers the advantages of high-purity, less labor intensive, consistent in production quality and less pollution.     

膜分离技术在低分子量生物产品分离纯化中的应用

介绍了膜分离技术在低分子量生产产品分离纯化中的应用。以压力差为推动力的膜分离技术包括微滤、超滤、纳滤、反渗透等，其分离性能通常由透过通量和截留率表征，而操作模式则分为浓缩和渗滤两种。本文将低分子量生物产品划分为氨基酸和多肽、抗生素、乳酸及低聚糖等，综述了膜分离技术在上述产品的回收、分离、纯化和浓缩过程中的研究与应用进展。     

Purification of Aspergillus carbonarius polygalacturonase using polymeric membranes

BACKGROUND: Microfiltration (MF: 70–450 nm) and ultrafiltration (UF: 10–500 kDa) membranes were used to eliminate carbohydrates and other non‐protein impurities from Aspergillus carbonarius culture broth containing polygalacturonase enzyme (EC 3.2.1.15) that would otherwise interfere with the purification processes and lead to enzyme loss. Further, diafiltration was attempted to improve the elimination of impurities as well as recovery of enzymes. RESULTS: MF resulted in removal of 2–25% carbohydrates with an enzyme recovery of 69–82% from the crude culture broth owing to the secondary layer formation. UF with 10 kDa membrane eliminated most of the carbohydrates (96%), phosphate salts and total acids with a recovery of 96% polygalacturonase and resulted in greater productivity. Using the above procedure, the enzyme was concentrated nearly 10‐fold while the purity improved from 4.6 to 49.4 U mg^?1 of dry matter. CONCLUSIONS: The results of this study focused on the elimination of carbohydrates and other non‐protein impurities showed that UF could be used efficiently as a primary purification step during downstream processing of microbial culture broths containing enzymes. The present approach will ensure complete elimination of non‐protein impurities thereby reducing the losses and difficulties in the subsequent purification steps. Copyright © 2008 Society of Chemical Industry     

Separation of the collagen protein by ultrafiltration: Effects of concentration on the membrane's characteristics

Collagen is one of the predominant proteins found in all multicellular animals. In this paper, the performance of the ultrafiltration process (UF) for concentrating the collagen protein was studied by performing batch experiments using a membrane module with an effective area of 28 cm² and equipped with a regenerated cellulose membrane with a molecular weight cut-off of 5 kDa. The feed solution consisted of aqueous solutions of bovine collagen hydrolysate with a molecular weight of 10 kDa. The effects of feed concentration (1%, 2%, 3%, 4%, and 5%) on the performance were determined. The optimum operating conditions were: a transmembrane pressure of 5 bar and a temperature of 25°C. The results showed that the permeability decreases with the increase of the volumetric concentration factor (VCF) for all five concentrated solutions of collagen tested. Also, the rejection of proteins increases with the increase in the concentration of the collagen solutions. The study confirms that the clogging phenomenon was dependent on the increase of concentration. Further, a mathematical modeling of fouling mechanism was analyzed based on Hermia's model. The concentration of the collagen solutions was also highlighted by viscosity measurements.     

Purification and Concentration of Caustic Mercerization Wastewater by Membrane Processes and Evaporation for Reuse

A membrane-based treatment strategy was developed for purifying the highly alkaline textile mercerization wastewater. 0.2-μm MF and 100 kDa UF membranes were evaluated as pretreatment alternatives before 10 kDa UF and 200 Da NF membranes. Turbidity was almost totally removed by both pretreatment options, while UF (100 kDa) showed higher COD retention than MF. In total recycle mode of filtration, fouling of both UF and MF membranes were 80% reversible by physical and almost totally reversible (≥ 97%) by chemical cleaning. In the second stage filtrations applied to the pretreated wastewater samples, NF could yield high (97-98%) COD retentions and low permeate COD concentrations (≤ 22 mg/L), while 10 kDa UF could only reduce the COD concentration to 150 mg/L. While no NaOH was lost in the MF+UF process, the use of NF as second stage resulted in 12-17% NaOH retention. The permeate flux in all second stage processes were stable, implying that the majority of the feed components that would cause fouling had been removed in the pretreatment stages. Permeate of the MF+NF sequence was concentrated by evaporation with no foaming problems, showing that the hybrid process can be applied to recycle a purified and concentrated caustic stream to the mercerization process.     

Review of the treatment of seafood processing wastewaters and recovery of proteins therein by membrane separation processes — prospects of the ultrafiltration of wastewaters from the fish meal industry

The wastewaters generated in fish meal production (average flow rates of 1100 m³/h for a plant capacity of 100 ton fish/h) contain a high organic load, and therefore they should not be discharged directly into the sea without effective treatment in order to prevent a negative impact on the environment. On the other hand, these effluents contain a large amount of potentially valuable proteins. These proteins can be concentrated by means of ultrafiltration (UF) and recycled into the fish meal process, improving its quality and the economic benefits from the raw material, whereas the treated water can be discharged into the sea or reused in the plant. Due to the high concentration of suspended matter in these effluents, microfiltration (MF) pre-treatment is required. An extensive review of the application of pressure-driven membrane separation processes in the treatment of seafood processing effluents and recovery of proteins therein is presented. Two effluents from a fish meal plant located in Talcahuano, Chile, were characterised and microfiltrated with a Whatman filter No. 1. A mineral tubular membrane, Carbosep M2 (MWCO = 15 kDa, ID = 6 mm and L = 1.2 m) was used in the UF experiments. The operating conditions were optimised in total recirculation mode, and the subsequent concentration experiments were carried out at 4 bar, 4 m/s, ambient temperature and natural pH. The results show that UF reduces the organic load from the fish meal wastewaters and allows the recovery of valuable raw materials comprising proteins. Moreover, they point out that further investigation should be dedicated to the use of UF membranes of lower molecular weight cut-off — or even NF membranes — in order to achieve complete recovery of the proteins contained in these effluents. Although the membrane undergoes severe fouling, it can easily be cleaned through a caustic washing.     

聚季铵盐辅助络合-超滤提取钨(Ⅵ)(英文)

Polyquaternium-6 (PQ6) as the water-soluble polymer was used for complexing the anion forms of tungsten (Ⅵ) before ultrafiltration. Tungsten (Ⅵ)-PQ6 complex was retained by polysulfone hollow fiber ultrafiltration membrane in the complexation-ultrafiltration process. Effects of various operating parameters such as polymer metal ratio(PMR), pH and chloride ion concentration on permeate flux (J) and tungsten rejection coefficient (R) were investigated. The integration of four experiments including concentration, decomplexation, diafiltration and reuse of regenerated polymer was carried out. In the process of concentration, J declines slowly and R is about 1 at PMR of 3 and pH of 7. Tungsten concentration in the retentate increases linearly with volume concentration factor. Tungsten is concentrated efficiently with the membrane. The concentrated retentate was used further for the decomplexation. It takes about 6 min to reach the decomplexation equilibrium at chloride ion concentration of 50 mg·L-1 . The decomplexation percentage of tungsten (Ⅵ)-PQ6 complex reaches 56.1%. In the diafiltration process, tungsten (Ⅵ) can be extracted effectively by using 50 mg·L-1 chloride ion solution, and the purification of the regenerated PQ6 is acceptably satisfactory. The regenerated PQ6 was used to bind tungsten (Ⅵ) at various pH values. The binding capacity of the regenerated PQ6 is close to that of fresh PQ6, and the recovery percentage of binding capacity is higher than 90%.     

Ultrafiltration of Coagulation-Pretreated Serratia marcescens Fermentation Broth: Flux Characteristics and Prodigiosin Recovery

The dead-end ultrafiltration (UF) of coagulation-pretreated fermentation broth of Serratia marcescens SMΔR for prodigiosin recovery was studied. Experiments were performed using different types (regenerated cellulose, YM; polyethersulfone, PES) and molecular weight cut-offs (MWCOs, 1–10 kDa) of the membranes, feed concentrations of prodigiosin (300–1000 mg/L), applied pressures (68.9–206.8 kPa), and stirring speeds (200–400 rpm). With the same MWCO, the YM membrane had a higher retention of prodigiosin and a lower flux than the PES membrane. A two-fold concentration of prodigiosin was observed in the retentate using a 1-kDa YM membrane compared to the concentration in the permeate using a 10-kDa YM membrane. In addition, the extent of membrane fouling was quantitatively analyzed in terms of the modified fouling index. Flux decline in the present batch UF process was mainly due to cake layer formation and partly due to pore blocking. A two-stage UF process was proposed for this purpose, with 81% recovery yield and four-fold concentration.     

浸没式超滤海水预处理工艺

目前渤海湾反渗透海水淡化工程多采用新型的超滤膜法预处理工艺,为提高预处理效果,主要进行超滤膜材料和性能改进以及膜组件运行参数的优化,而对超滤膜前预处理的研究相对较少。本实验研究了超滤与混凝/超滤作为反渗透海水淡化预处理工艺的处理效果。考察了两种预处理工艺条件下浸没式超滤膜比通量(SF)、进水水质、产水水质,膜孔孔径变化、反洗效果及膜表面污染情况。结果表明,超滤与混凝/超滤两种预处理工艺都能达到产水SDI₁₅<2.0;混凝处理可以大幅度降低海水中颗粒数目,降低颗粒物在膜表面沉积和吸附的概率,减轻超滤膜的污染。当采用混凝/超滤工艺时超滤膜表面滤饼层疏松多孔,膜孔孔径变化较小,超滤膜比通量的衰减速度减缓,反洗时超滤膜比通量恢复率较高。     

Elimination of organic matter present in wastewaters from the cork industry by membrane filtration

BACKGROUND: The first stage of the cork industrial process generates great volumes of wastewater with moderate to high organic pollutant content that must be purified using different procedures, such as filtration by membranes. RESULTS: The tangential filtration of these wastewaters was studied using two different laboratory equipments. In the first one, three ultrafiltration (UF) membranes were tested, with molecular weight cut‐off (MWCO) 100 kDa and 30 kDa, and two operating modes were used: total recycling of permeate and retentate streams, and in continuous mode, without recycling both streams. In the total recycling UF experiments, the influence of the operating variables on the permeate flux was first established. The effectiveness of the different membranes was determined by evaluating the rejection coefficients for several parameters that measure the global pollutant content of the effluent. The values found for these rejection coefficients were in the following order: ellagic acid and color > absorbance at 254 nm > tannic content > COD (chemical oxygen demand). In the continuous mode experiments, the fouling mechanism for each membrane was established by fitting the experimental data to various filtration fouling models given in the literature. The operating mode in the second equipment was batch concentration, and additional experiments were carried out with an UF membrane (2 kDa), and with a NF membrane (with MWCO in the range 150–300 Da). CONCLUSIONS: The three operating modes tested provided different rejection levels of organic matter; among them, the most effective procedure tested was batch concentration mode using a NF membrane. Copyright © 2007 Society of Chemical Industry     

UF,NF处理酵母废水可行性研究

采用ＵＦ或ＮＦ技术可以处理酵母生产中不同阶段高浓度有机物的废水，废水经ＵＦ膜处理可１００％回收酵母蛋白等成份，对色度浊度具有〉９０％的去除率，从浓缩液中回收的酵母蛋白等成份，经进一步浓缩干燥可作动物饲料添加剂，干燥物蛋白质含量〉３０％，膜透过液含有发酵过程所需的营养成分，可重新用于发酵生产用水。废水用ＮＦ膜处理对ＣＯＤ去除率〉９０％并接近或达到排放标准，对于直接从发酵液中经高速离心分离的酵母废水（     

Grey water treatment and simultaneous surfactant recovery using UF and RO process

The membrane-based grey water treatment for grey water reuse and surfactant recovery is presented in this research paper. Grey water from washing machine discharges having turbidity and used surfactant was processed through the polymeric ultrafiltration (UF) membrane to remove the turbidity. The UF treated grey water is further purified by reverse osmosis (RO) membrane for surfactant recovery and water reuse. The surfactant trapped inside the RO spiral wound membrane module is recovered through various membrane physical regeneration techniques such as backwashing, simultaneous backwash–back-flush and ozone back-flush. Among this, backwash–back-flush is found to be effective process for surfactant recovery. The methodology for optimising surfactant recovery is captured by studying effect of various operating parameters such as feed detergent concentration, backwash pressure, backwash temperature and back-flush flow rate. By implementing optimal process conditions, the integrated UF and RO membrane process is able to produce 300 L of reusable pure water and 80 L of concentrated detergent solution and 20 L of turbid water while treating 400 L of grey water discharges. Maximum surfactant recovery of 82% is obtained while treating grey water which consists of 720 ppm of total dissolved solids (detergent) and 45 ppm of surfactant. The extent of UF and RO membrane fouling is determined by measuring the pure water flux before and after the grey water treatment. The membrane performance is found to be stable when membrane is regenerated by backwash–back-flush technique for RO and gravity backwash for UF membrane.     

大规模生产静脉注射用人血免疫球蛋白工艺的研究

本文介绍一种制备静脉注射用人血免疫球蛋白(IVIG)的工艺。工艺流程为:以低温乙醇法的 FⅢ上清为原料,经 NMWL 为3万的超滤膜脱醇,DEAE-Sephadex-A-50吸附,pH3.8～4.0条件下超滤,最后添加麦芽糖等稳定剂冻干。本工艺具有收率高、质量好、生产过程简单温和、经济效益显著等特点,适于大规模生产。     

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.     

Whey fractionation through the membrane separation process

The aim of this work is to improve the utilisation of fractions of whey through membrane separation processes. From a solution of whey treated by ultrafiltration (UF) associated with diafiltration (DF), two streams were obtained: a concentrate and a permeate. In this process, a purified protein concentrate with about 70% of protein was obtained. Permeate was treated by electrodialysis (ED) to obtain a fraction rich in lactose (90%). The final effluent was treated by reverse osmosis (RO) in order to recover water free of salts. RO made it possible to recover 50% water and retain 85% of the salts.     

Preparation of Rapeseed Proteins by Extraction,Ultrafiltration and Diafiltration

From industrial Rapeseed mean (Brassica napus, Var. Sollux) different protein preparates are prepared by varying extractions (water extraction, extraction with 1% CuSO₄ solution, extraction with 5% sodium chloride solution) following ultrafiltration (UF), diafiltration (DF) and drying. The UF, UF/DF respectively is a comparatively simple process for concentration and purification of all solved proteins without losses (globulins and above all albumins). The UF/DF treatment of a 5% sodium chloride solution protein extract leads to a preparate containing more than 90% protein in which glucosinolates and splitting products and also phytate are not detectable.     

多孔陶瓷膜用于碳量子点的分离与纯化

尺寸分布均一的碳量子点由于其良好的光学特性,在光电设备、离子检测、纳米传感器、生物成像和催化剂等领域具有广阔的应用前景。采用陶瓷膜“超滤-纳滤”双膜法,对微波合成的碳量子点进行分离和纯化。研究了pH对碳量子点料液荧光强度和粒径分布的影响。在pH=3时,碳量子点分散较好,荧光强度较高。陶瓷超滤膜可以有效截留碳量子点料液中的大颗粒杂质,渗透侧的碳量子点平均粒径约为2 nm,分散良好,无团聚现象。陶瓷纳滤膜对碳量子点具有良好的截留性能,在浓缩和水洗过程中可以进一步去除料液中的小分子杂质。经双膜法处理后,发射光谱由多峰分布变为单峰分布,且峰宽变窄,碳量子点的发光纯度得到了明显提高。     

高浓度含盐草甘膦溶液的纳滤分离实验研究

为了考察纳滤技术分离含高浓度单价盐的草甘膦溶液的可行性,采用商业化Desal-DK纳滤膜对含有高浓度NaCl的草甘膦溶液开展了分离实验研究和模拟计算。首先研究了物料浓度、跨膜压差等因素对NaCl和草甘膦的单组分溶液的体积通量及截留率的影响,并通过拟合SK（Spiegler-Kedem）方程计算得到了膜的特征参数;其次探究了Desal-DK纳滤膜对高浓度NaCl和不同浓度草甘膦混合溶液的分离效果,实验结果说明Desal-DK纳滤膜对NaCl呈现较高的透过性,而对草甘膦则呈现较高的截留性,从而能够有效实现草甘膦和NaCl的分离;最后通过对含有100 g/L NaCl和1 g/L草甘膦的混合溶液进行预浓缩-连续恒容渗滤过程的模拟计算,得到了较高浓度的草甘膦溶液和相对较纯的NaCl溶液,证明通过纳滤渗滤过程实现含草甘膦浓盐水的资源化利用是可行的。     

超滤和纳滤膜分离提取纳他霉素

为提高纳他霉素(natamycin)生产提取得率,减少溶剂使用,本文采用超滤、纳滤操作对工业生产的纳他霉索发酵液进行处理。实验结果表明:操作压力、操作时间及料液流速对超滤过程有很大影响。通过超滤可将蛋白质等大分子杂质去除,然后再用纳滤膜对超滤渗透液进行浓缩纯化,对纳滤工艺的操作条件如进料压力、料液pH、浓缩倍数等进行了研究。采用超滤、纳滤技术提取纳他霉素,其收率可达62.74%。     

膜分离技术在垃圾渗滤液处理中的应用

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。