新型温敏超滤膜处理印染废水的研究

印染废水中含有大量有机染料和重金属等物质,对生态环境及人类健康产生了严重的危害。以聚（N-异丙基丙烯酰胺）@聚苯乙烯（PNIPAM@PS）球形聚合物刷为主体,Cd（OH）₂纳米线作为牺牲层,聚碳酸酯（PC）膜为支撑层,经简单过滤制备得到对温度有响应性的高分子超滤膜。通过傅里叶变换红外光谱（FT-IR）、扫描电镜（SEM）、动态光散射仪（DLS）及水接触角测量仪对其进行表征,结果表明该超滤膜表面由PNIPAM@PS球形聚合物刷构成,其表面平整,结构规则,且具有良好的温度响应性。随后考察了PNIPAM@PS超滤膜对有机染料（甲基蓝和罗丹明B）和CdSe重金属颗粒的过滤效果,并通过紫外分光光度计（UV-vis）、原子荧光光谱仪（PL）等对其进行表征。结果显示,随着PNIPAM链增长、PS核粒径减小、实验操作压力增大,超滤膜的过滤效果显著改善。同时超滤膜的孔径可以通过温度实时调节,当环境温度高于PNIPAM链的LCST时,超滤膜的孔径较大;温度降低,超滤膜的孔径变小。PNIPAM@PS超滤膜的孔径可调节性使其在废水处理中有着广泛的应用前景。     

铜电解液过滤系统的技术改造与运用

分析了某铜业公司电解厂过滤系统中存在的主要问题,并相应采取了对压滤机和净化过滤机进行技术升级改造的解决措施。改造后,阳极泥含铜率从22.3%下降至15.8%,阳极泥含水率由35.2%下降至21.5%,阴极铜优品率得到显著提升。     

驻极处理对聚乳酸熔喷材料性能的影响

采用生物可降解性聚乳酸（PLA）为原料,采用熔喷工艺开发一种高性能过滤材料,并利用外置式电晕放电技术对材料进行驻极处理。分析讨论了驻极电压、驻极时间以及两电极之间距离等工艺参数对材料的表面电位、透气性及过滤性能的影响。采用扫描电子显微镜观察了驻极处理后PLA熔喷材料表面形貌结构的变化。结果表明：驻极后PLA熔喷材料表面粗糙度增加;材料在驻极电压增加过程中出现反极性充电现象。随着驻极电压和时间的增加,材料表面静电电位逐渐增加,然后又呈现下降的趋势。驻极处理后材料的透气性未出现显著变化;过滤效率显著提高。     

壳聚糖和pH对CHO细胞收获液澄清效率的影响

作者研究了壳聚糖和pH对中国仓鼠卵巢细胞(Chinese hamster ovary,CHO)培养液料液澄清过程的影响。初步探索了在CHO细胞收获液(pH 7.0)中添加0~0.10 g/d L壳聚糖对0.22μm膜过滤通量的影响。结果显示,添加0.06 g/d L壳聚糖时膜过滤通量最大,达到8 266.22 L/(m2·h)。探索了pH值(5.0~7.0)对收获液澄清效率的影响,研究发现,不添加壳聚糖的情况下降低培养液pH值对膜过滤通量没有十分显著的提高。为更多地去除宿主细胞蛋白(Host Cell Protein,HCP)和残留DNA,作者研究了pH值与壳聚糖对膜过滤通量及残留杂质的交互影响。结果表明,pH为5.0壳聚糖质量浓度为0.06 g/d L时滤出液中残留DNA几乎完全去除,HCP含量降低50%以上,而抗体的回收率不受影响。     

新型过滤机在工业领域的应用

论述新型自动厢式压滤机和带式真空过滤机的工作原理及其应用;介绍其他过滤机在工业领域的应用情况,并简述常用过滤介质的类别、物性与新型彗星式纤维滤料的特点和应用。     

浅析虹吸刮刀离心机在沸石生产中的应用

为了降低成本引进了虹吸刮刀离心机,分析了其原理、特点及可行性。经过生产运行的探索,离心机与立式压滤机相比,具有节能、运行费用低、维护方便、产品质量高等特点,有效地降低了生产成本。     

Coalescence/Filtration of an Oil-In-Water Emulsion in an Immobilized Mucor rouxii Biomass Bed

Breakdown mechanisms and flow characteristics involved in an immobilized M. rouxii biomass bed treating oil-in-water emulsion were investigated. The purpose of this research was to evaluate the applicability of the well-known Carman-Kozeny filtration equation to a 1000 mm immobilized M. rouxii biomass bed treating a standard mineral oil-in-water emulsion at six different flow rates (12, 16, 20, 24, 28, and 32 mL/min). The specific permeability coefficient, the Carman-Kozeny constant, and the shape factor of immobilized M. rouxii bed were found to be 2.135 × 10^?8 m², 5.03, and 1.13, respectively. The coalescence efficiency decreased with an increase in bed depth (from 15.9% at 200 mm to 4.0% at 1000 mm depth for a flow rate of 12 mL/min). Results indicated possible sequential occurrence of coalescence and filtration in the immobilized M. rouxii biomass bed.     

Integrated Membrane Bioreactor for Water Quality Control in Marine Recirculating Aquaculture Systems

The aquaculture live feed organisms Acartia tonsa (a calanoid copepod, experiment 1) and Brachionus “Cayman” (a rotifer, experiment 2) were cultivated in marine recirculating aquaculture systems (RAS), respectively. The pilot plant was built as a combination of conventional RAS (cRAS) and as a modified RAS which implemented an ultrafiltration membrane bioreactor (MBR) for the removal of fine suspended solids and colloidal particles as part of the treatment system (mRAS). The two treatment schemes were connected to the same biofilter (a moving bed bioreactor). In the first experiment, the membrane was operated with no extraction of concentrate, and hydraulic retention time (HRT) of 6 hours (i.e., water exchange in the cultivation tanks of 4 times per day). In the second experiment, the membrane was operated with daily extraction of concentrate, and HRT of 12 hours. Results show that the MBR option is more efficient in removing particles from the recycle stream than conventional RAS. However, the impact this has on the number of particles in the live feed cultivation tanks is not readily apparent based on particle analysis. The amount of suspended solids added during feeding exceeds the amount removed in the recycle system. This requires a higher recirculation rate and different membrane operating conditions.     

Separation and Fractionation of Oligouronides by Shear‐Enhanced Filtration

Abstract

This paper investigates the separation of anionic oligosaccharides produced by thermal degradation at 120°C of polygalacturonic acids (PGA). Initially, the PGA solution was clarified by two successive centrifugations. These centrifugations were later replaced by two microfiltrations (MF) which did not modify oligosaccharides composition. A dynamic filtration module with a disk rotating at 2000 rpm near a circular organic membrane was used in all filtration steps. Several micro‐ and ultrafiltrations (MF and UF) in cascade (50, 20, and 10 kDa) and a nanofiltration at 1 kDa were used to separate oligomers with degrees of polymerization (Dp) ≤7. Permeate fluxes ranged from 400 Lh^?1m^?2 for the first MF to 240 Lh^?1m^?2 for the 10 kDa UF and 60 to 100 Lh^?1m^?2 for the 1 kDa NF, showing the high potential of dynamic filtration for this application.     

Irreversible Fouling in MF/UF Membranes Caused by Natural Organic Matters (NOMs) Isolated from Different Origins

Abstract

For more efficient use of membrane technology in water treatment, it is essential to understand more about the fouling that requires chemical cleaning to be eliminated (i.e., irreversible fouling). In this study, five different MF/UF membranes and four types of organic matter collected from different origins were examined in terms of the degree of irreversible membrane fouling. Experimental results demonstrated that the extent of irreversible fouling differed significantly depending on the properties of both the membrane and organic matter. Among the tested membranes, UF membranes made of polyacrylonitrile (PAN) exhibited the best performance in terms of prevention of irreversible fouling. In contrast, MF membranes, especially one made of polyvinylidenefluoride (PVDF), suffered significant irreversible fouling. Conventional methods for characterization of organic matter such as specific ultraviolet absorption (SUVA), XAD fractionation, and excitation‐emission matrix (EEM) were found to be inadequate for prediction of the degree of irreversible fouling. This is because these analytical methods represent an average property of bulk organic matter, while the fouling was actually caused by some specific fractions. It was revealed that hydrophilic fraction of the organic matter was responsible for the irreversible fouling regardless of the type of membranes or organic matter.