采用双膜法处理矿井水回用过程中的问题

矿井水成分复杂,在采用双膜法处理矿井水回用过程中对其预处理的要求非常高,如果某处工艺发生短路,势必会使膜元件受到严重污染,甚至使产品水质不合格并造成生产瘫痪。针对某热电厂采用双膜法处理矿井水回用过程中存在的问题,作者采用离线和在线清洗等方式,使系统恢复了正常稳定运行,并根据实际运行情况提出了建议。     

纳米技术应用于水处理膜材料制备研究进展

水资源短缺、水污染和饮用水安全已经成为全球性挑战。膜技术被认为是21世纪的水处理技术,已广泛应用于饮用水深度处理、海水淡化、工业废水回用处理等领域。传统膜多采用压力驱动膜分离技术,按照膜孔尺寸分类,包括可用于去除大颗粒悬浮物、细菌、原生动物的微滤膜,用于去除胶体和大分子有机物的超滤膜,用于去除硬度、重金属、有机物的纳滤膜,以及用于脱盐、水回用和制备超纯水的反渗透膜。在过去的几十年间,纳米材料技术发展迅速,纳米技术被广泛应用于水处理膜材料制备中,纳米技术在膜材料的应用,可以大大提升膜的通量、耐污染等基础性能,使膜具备催化、杀菌等特殊功能性。总结了纳米技术在有机无机共混膜、薄膜纳米复合膜以及纳米材料膜表面修饰中的应用研究进展,并讨论了其未来的发展方向。     

超滤分离技术在水处理中的应用

近些年来,超滤膜分离技术在饮用水制备、污水处理及回用等领域取得了不少新成果,应用前景广阔。文章论述了超滤膜分离技术在饮用水制备、油/水乳浊液处理、纤维工业及造纸工业废水处理上的应用研究概况,还阐述了超滤膜分离技术的工作机理、超滤膜材料及膜制备、超滤膜组件、超滤膜的污染及清洗等情况,展示了该技术在水处理中的应用和发展趋势。     

纳滤膜分离技术在矿井水处理中的研究

介绍了用纳滤膜处理含悬浮物矿井水的工艺流程．考察了纳滤膜不同操作特性对膜过滤性能的影响及组合工艺对矿井水的处理效果。试验结果表明：纳滤膜在过滤周期为30min采用反曝气方式冲洗,能够有鼓减少膜污染,恢复膜通量。该工艺对矿井水的处理效果明显,出水稳定,出水达到国家饮用水标准,是一种高效、经济的处理工艺。     

微污染水源水处理技术研究进展

以微量有机物,氨氮污染为主要特征的微污染水源水给常规水处理工艺提出了挑战.常规水处理工艺对此类水源水的处理效果很差,难以达到国家的饮用水标准.通过对多种水处理技术包括强化常规处理技术,化学及生物预处理,高级氧化、吸附和膜处理技术等在微污染水源水处理中的原理、作用及优缺点等进行了探讨.     

纳滤膜技术和微污染水处理

饮用水水源的污染日益严重,对人类的健康带来了极大的危害,对净水技术提出了新的挑战。常规水处理工艺对微污染水的净化很难达到健康饮用水标准,纳滤膜分离技术能很好地实现对微污染原水的彻底处理,出水水质稳定安全,完全可达到健康饮用水标准。对纳滤膜分离技术,纳滤膜技术在微污染处理中的作用,纳滤技术处理微污染水的工艺、预处理、膜污染以及经济性进行了介绍和分析。     

反渗透技术用于高矿化度矿井水处理的研究

采用反渗透技术对高矿化度矿井水进行处理,考察了CPA(芳香族聚酰胺)膜对矿井水中各种离子的去除效果.试验结果表明:系统运行24 d,对矿井水的处理效果显著,Ca2+、Cl-、SO2-4、Mg2+各离子的平均去除率可分别达到98%、94%、98%、95%以上,系统出水水质稳定,出水达到国家饮用水标准;并根据静态清洗反渗透(RO)污染膜的分析结果,总结出反渗透膜的污染特征,最终优选出先碱洗后酸洗的膜清洗方案.     

宁东基地高矿化度矿井水处理工程实践与发展方向

为了实现宁东基地矿井水的大规模低成本处理,缓解基地水资源短缺的问题,详细分析了宁东基地矿井水处理的工程实践,并围绕低成本热源利用、缩短工艺流程、井下处理等探讨了高矿化度矿井水处理的发展方向。宁东基地矿井水均为高矿化度矿井水,现有矿井水处理工程实践包括常规处理、预处理+反渗透深度处理和零排放处理,所用单元技术较为成熟,但深度处理浓水排放难,零排放处理工艺复杂、成本高等问题依然存在。利用电厂余热的低温多效蒸发可取代反渗透进行高矿化度矿井水地面脱盐,成本低且产水品质好;膜蒸馏结合新能源可在地面或井下对高矿化度矿井水进行浓缩处理,但应充分考虑"能源互补"。井下处理与浓盐水封存能很好地缓解深度处理浓水排放难的现状,克服常规零排放成本高的不足,但需要突破合理选址、设备集成、安全保障等技术难点。     

粘土矿物强化混凝处理微污染水源水研究现状与进展

近年来,藻华的爆发以及重金属污染使水源水污染日益加重,严重威胁到饮用水安全,常规水处理技术已无法满足人们对饮用水的水质要求,亟待寻求一种安全、高效、经济的处理微污染水源水的技术和方法。本文针对粘土矿物价格低廉、资源丰富、有优良吸附性能等优点,综述了将不同粘土矿物进行改性、复合并与混凝剂联用处理微污染水的应用效果并进行对比,揭示了该技术存在的不足以及未来的发展方向,为今后处理微污染水新技术提供理论支持和技术参考。     

双膜系统在化工废水深度处理中的应用

云天化股份有限公司废水深度处理及回用工程采用UF+RO双膜工艺,处理后的产品水作为生产水回用。实际运行结果表明,UF+RO双膜工艺能有效去除污水中的有机物、SS和各种阴阳离子。出水水质能够达到炼油企业污水回用管理规范中"优质工业再生水水质指标",从而节约大量新水,产生了良好的经济效益和环境效益。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。