反渗透膜有机物污染及微生物清洗的研究

在膜集成技术处理印染废水的工程调试中,研究了生物预处理中有机物浓度对反渗透膜污堵的影响,结果表明:反渗透膜进水COD100mg/L时,系统运行稳定,产水达到优质软化水指标;当反渗透膜进水COD为110～180mg/L时,产水仍达到优质软化水指标,但污堵严重,并且化学清洗无效.经分析认为膜的污染为有机物结垢,据此进行了厌氧茵去除反渗透膜有机物垢的试验.试验表明:接种厌氧茵105CFU/mL,温度保持在30℃,浸泡80h,可有效地去除有机垢的污染,膜的性能没有变化.用微生物清洗有机物污染的反渗透膜是一种有效的新方法.     

超滤系统运行分析研究

超滤膜能够对胶体、大分子有机物、细菌等进行有效截留,其出水可完全满足反渗透系统的要求。超滤装置实际产水量同进水压力、水温(水的粘度)、膜污堵程度(跨膜压差TMP)、进水水质(悬浮物、有机物、微生物、浊度等)、充水排气状况等因素有关。文章研究了操作压力、跨膜压差、进水温度和进水水质对产水量的影响。     

某钢铁厂污水回用项目反渗透膜污染的分析和清洗

经过污堵物质的分析,采用了合适的复合药剂,利用成熟的膜清洗工艺流程对膜组件进行了清洗研究。     

利用膜技术直接处理碎煤加压气化工艺污水中试研究

介绍了采用膜技术直接处理碎煤加压气化工艺污水的中试,分析了试运行中膜的污堵原因,有针对性地提出了各项措施,对延长膜的污堵周期取得了明显效果。经过膜处理后,淡水水质满足循环水回用要求,初步验证了在处理碎煤加压气化工艺污水时,膜具有较长使用寿命,在经济上具有可行性。     

反渗透膜污堵的原因及防治措施

介绍了安徽华塑股份有限公司脱盐水站反渗透膜污堵的原因及采取的措施。通过工艺改进,调整药剂投加量,低压冲洗膜表面的附着物,加大预处理进水指标的控制,使得反渗透清洗行周期延长2倍多。     

中空纤维反渗透器的污堵与酸洗

本文主要叙述了B-9反渗透装置的污堵与进水污染指数的关系;进水压力对半透膜性能的影响;酸洗工艺的选择及注意事项。文中还就反渗透器酸洗前、后的性能变化进行了比较,通过比较对其透水率、脱盐率以及半透膜的压密化系数等参数的变化规律作了较详细的阐述。进一步改善反渗透器的进水水质,特别要使进水污染指数经常<2,并采用低压交变运行方式,以延长反渗透器的酸洗间隔,从而达到延长其使用寿命之目的。     

膜处理单元保安过滤器污堵原因及清洗恢复试验

宁夏某化工厂矿井水膜处理单元保安过滤器在运行中出现了压差上升过快、滤芯更换频繁问题,严重影响后端反渗透系统的高效稳定运行,对污堵滤芯进行了碱洗,清洗效果较差。为确定污堵原因,对过滤器进水水质及滤芯上污染物成分进行了系统分析,判断预处理工段投加的聚铝絮凝剂首先在滤芯上发生沉积,后续金属离子(Ca²⁺、Si²⁺等)、有机污染析出附着在絮凝剂层上形成混合污染物,最终造成滤芯彻底污堵。通过开展清洗试验制定了有效的清洗方案,清洗后上线的滤芯运行状况良好,为水处理工程中滤芯的污堵原因及清洗恢复研究提供了系统、可行的思路指导。     

中原乙烯反渗透装置膜压差高原因浅析

针对反渗透装置膜压差高问题,经过观察分析膜元件的清洗过程,以及对膜间污堵物化验处理,找到了膜压差高原因,并提出了相应的防范措施。     

十二烷基苯磺酸钠在反渗透膜系统化学清洗过程中的应用浅析

反渗透膜系统在运行过程中必定会产生污堵现象,本实验过程中分析认为是胶体和有机物对膜造成了污堵,遂利用十二烷基苯磺酸钠进行清洗,取得了较好的效果.     

采用膜法回收循环冷却水工艺的完善

循环冷却水含盐量高、硬度高、碱度高,因此结垢趋势强,必须采用调酸的方式控制pH,以缓解结垢趋势.某循环冷却水系统以部分膜法回收的污水作为补充水使用,由于膜处理工艺中设计的絮凝时间不够,因此造成反渗透系统被严重污染,影响到循环冷却水系统的正常使用.为此在膜工艺中增加了超滤处理,解决了污堵问题,确保了系统的安全运行.     

180万t/a煤制甲醇项目水煤浆气化装置水系统结垢原因及技改措施

从机理、工况两方面分析了180万t/a煤制甲醇项目之德士古水煤浆加压气化装置水系统结垢、堵塞的原因;提出了安装除氧器、使用高效絮凝剂、添加纯碱降低水系统永久硬度等技改措施。结果表明:水系统结垢问题得到了有效缓解。     

旁流弱酸处理应用于循环冷却水的试验研究

循环冷却水采用旁流弱酸处理后,由于工艺改变了循环水运行的碱度、硬度,对判断循环水系统是否结垢带来了困难。通过在循环冷却水的动态模拟试验过程中监测凝汽器管的污垢热阻,循环水的碱度、硬度、pH的变化以及试验结束后观察试片的表面状态等方法,对循环水系统是否结垢进行了探讨。     

pH adjustment for seasonal control of UF fouling by natural waters

Natural surface waters in Algarve, Portugal, have important seasonal variations in natural organic matter (NOM) content, that influences ultrafiltration (UF) performance. This paper addresses the evaluation of the pH adjustment for seasonal control of UF fouling at a laboratory scale, using a plate and frame polysulphone membrane of 47 kDa MWCO. Results of two types of natural water (clear water, 3-5 NTU, and turbid water, 33-34.6 NTU) and three different water pH values (acid, neutral and basic) demonstrated that the pH adjustment could be used for seasonal control of UF fouling: when the water has less NOM (in dry periods, clear water), the acid pH will improve the UF performance, while during and after intense rainfall periods (turbid water with high NOM concentration) basic pH will be advantageous, because it minimizes membrane fouling. This behaviour is explained for clear water in terms of charge effects on membrane size. For turbid water, the electrostatic repulsion between membrane surface and NOM and turbidity particles is reduced at pH 4.13 and protonation of the NOM functional groups decreases the hydrodynamic radii of humic substances while increasing their hydrophobicity and their tendency to adsorb. Therefore, a dense fouling layer develops and flux is lower at pH 4.13 than at pH 8.33. These results together with the observed raw water feed concentrations decline and rejection decrease with WRR confirm the extensive adsorption on the membrane enhanced by the moderate hardness cation of this water.     

SBS型热塑性弹性体的加工技术和性能研究

报道了SBS热塑性弹性体混合料的性能研究。探讨了软化油、聚苯乙烯,填料含量以及填料品种对材料性能影响,研究过氧化物交联对材料性能影响,比较了SBS星形结构和线形结构及其并用对材料性能的影响。结果表明,化学交联对材料性能影响甚微;星形结构具有较高的撕裂强度,线形结构的拉伸强度和硬度较高;软化油含量对材料性能影响较大;轻质碳酸钙使材料具有最高的性能价格比,白炭黑真充料的综合性能最佳。     

基于裹浆工艺的煤矸石混凝土性能研究

采用裹浆工艺对煤矸石骨料进行预处理,研究原状煤矸石骨料与不同浆体裹浆煤矸石骨料的吸水率、压碎值和干湿、冻融环境下的劣化行为以及裹浆煤矸石混凝土的强度和耐久性能,并分析骨料性能强化与混凝土性能提升的相关性。采用XRD、SEM分析原状煤矸石骨料与裹浆煤矸石骨料干湿、冻融循环前后的矿物组成、微观形貌和界面过渡区。结果表明,原状煤矸石骨料吸水率高,硬度低,在干湿、冻融环境下劣化明显,裹浆后煤矸石骨料性能提升。原状煤矸石混凝土强度与耐久性能较差,裹浆后煤矸石混凝土性能得到增强,骨料性能与混凝土性能相关性良好。煤矸石骨料劣化的主要原因是黏土矿物吸水后在干湿、冻融环境下软化失稳,而裹浆可以起到隔绝水分的作用,从而使骨料性能得到强化。骨料强化以及骨料与砂浆基体的结合程度提高共同促进了裹浆煤矸石混凝土性能提升。     

高皂基及低皂基主洗液在洗衣房布草洗涤中的应用

本研究设计了高皂基、低皂基两种主洗液,考察了水质对主洗液去污性能的影响,并对体系的控泡性能进行了测定。结果表明,水质在洗衣房布草清洗中起着至关重要的作用,洗涤化料对于蛋白污垢和皮脂污垢的去除能力随着水硬度的上升而快速下降。此外,高皂基主洗液和低皂基主洗液在同等硬水条件下去污能力相差并不是很大,但其泡沫表现差别巨大。     

Evaluation of coagulation and PAC adsorption pretreatments on membrane filtration for a surface water in Korea: A pilot study

Application of membrane filtration has been significantly expanded throughout the world in two decades. A project was launched to facilitate the application of membrane filtration in drinking water plants in Korea in 2004. Five pilot plants each with a capacity of 500 m³/d were installed in a Gueui Drinking Water Plant. The Han River water was a main raw water source for the plants. Key parameters of the raw water were examined. The raw water characteristics are tremendously varied with seasons and rain fall, especially in terms of turbidity and algae numbers. The operation of pretreatment was of substantial importance due to the variation of the raw water. Coagulation and powdered activated carbon adsorption were performed as pretreatment options of microfiltration. The coagulant doses were optimized with increasing turbidity compared to the conventionally used operational manual. PAC adsorption was applied to overcome fouling by high algae numbers. The addition of PAC relieved the aggravation of fouling. However, the PAC addition could not stop the undergoing fouling. A set of laboratory experiments showed that the removal of floc aggregates after coagulation and PAC was critical to maintain high water flux in the membrane system.     

低压静电用于循环冷却水阻垢的实验研究

对低压静电处理循环冷却水的阻垢性能进行了实验研究与机理分析。采用动态监测污垢热阻的方法进行了结垢与阻垢实验,并对溶液的水质进行了分析。结果表明,低压静电处理循环冷却水对换热表面的结垢起到很好的抑制作用,实验中仅需2.2W功率就可达到100%的阻垢率。低压静电水处理不同与其它物理水处理技术,它可降低溶液的硬度、碱度、电导率及pH值,是一种主动的抗垢技术。被处理溶液中发生的微电解反应使更多的污垢晶体在处理器中聚集并生长,而不是沉积在换热表面,从而起到阻垢作用。     

A review on the forward osmosis applications and fouling control strategies for wastewater treatment

During the last decades, the utilization of osmotic pressure-driven forward osmosis technology for wastewater treatment has drawn great interest, due to its high separation efficiency, low membrane fouling propensity, high water recovery and relatively low energy consumption. This review paper summarizes the implementation of forward osmosis technology for various wastewater treatment including municipal sewage, landfill leachate, oil/gas exploitation wastewater, textile wastewater, mine wastewater, and radioactive wastewater. However, membrane fouling is still a critical issue, which affects water flux stability, membrane life and operating cost. Different membrane fouling types and corresponding fouling mechanisms, including organic fouling, inorganic fouling, biofouling and combined fouling are therefore further discussed. The fouling control strategies including feed pre-treatment, operation condition optimization, membrane selection and modification, membrane cleaning and tailoring the chemistry of draw solution are also reviewed comprehensively. At the end of paper, some recommendations are proposed.     

PAC-UF处理含蛋白质类溶液过程中的膜污染研究

使用粉末活性炭(PAC)-超滤(UF)组合工艺处理牛血清白蛋白(BSA)溶液,研究了不同PAC投量下组合工艺的膜污染情况。结果表明,PAC本身对膜污染无明显贡献,PAC吸附BSA后使得膜通量急剧下降;PAC对改善BSA溶液通过超滤的膜通量和膜污染阻力均有一个最佳投加值;PAC在膜表面形成的滤饼层对膜通量改善作用明显;PAC滤饼层主要形成可逆污染,而水中BSA则是不可逆膜污染。