混凝过滤-超滤-膜系统深度处理酒精废水试验研究

采用混凝过滤-超滤-膜系统对酒精废水的二级生化出水进行了深度处理,探讨了混凝过滤-超滤预处理对COD、浊度的去除效果,考察了反渗透膜的脱盐性能及不同清洗方式对反渗透膜通量恢复的影响。结果表明,混凝过滤-超滤预处理对废水COD和浊度去除效果显著,其对应去除率达到40%和99%以上;膜系统产水浊度、硬度、总铁质量浓度分别小于0.1 NTU、0.03 mmol/L和0.3 mg/L,电导率处于60～120μS/cm之间;混凝过滤出水和反渗透产水分别满足循环冷却水补充用水和锅炉补充水要求,混凝过滤配合消毒处理费用0.71元/m3,混凝过滤-超滤-膜系统处理总成本2.94元/m3,整套工艺具有较好的应用前景。     

中水全膜处理系统在热电厂的应用

大连泰山热电厂采用超滤(UF)—反渗透(RO)—电除盐(EDI)工艺对马栏河污水厂二级出水进行深度处理,使其满足热电厂超高压锅炉补给水水质要求。作者介绍了系统工艺的设计及设备的运行等,经该工艺处理后的出水可以达到设计要求。通过中水回用,热电厂每年可节约淡水6.25×106 m3,节省资金1 800多万元,社会及经济效益显著。     

渤海湾海水混凝-超滤预处理工艺研究

采用混凝-超滤工艺对渤海湾海水进行了预处理实验,在50 L/(m2·h)和57.5 L/(m2·h)通量下考察了混凝-超滤系统的运行稳定性,研究了Fe Cl3混凝沉淀过程对超滤系统出水水质、跨膜压差及膜表面污染程度的影响。结果表明:在膜组件运行通量不超过60 L/(m2·h),温度高于14℃,Fe Cl3投量为6 mg/L时,超滤系统的跨膜压差较低,可长期稳定运行,超滤系统出水浊度小于0.15 NTU,SDI15稳定在2.0左右,达到反渗透进水水质要求。实验使用Darcy模型对膜阻力增长机理进行了分析,结果表明:Fe Cl3混凝预处理可有效减缓膜阻力的增长,特别是因膜孔内污染物堵塞和吸附产生的阻力。经过混凝沉淀预处理,膜表面的滤饼层明显松散并呈现絮体状,可有效阻挡小颗粒污染物进入膜孔内造成不可逆污染。     

超滤一体化装置处理闽江高含藻原水的效果

考察了集混凝—斜管沉淀—超滤于一体的装置在高藻水期对闽江水的净水效果。结果表明超滤一体化装置出水浊度小于0.1 NTU,浊度去除率达到99%以上;出水CODMn均值为1.40 mg/L,出水UV254为0.024 cm-1,CODMn和UV254去除率分别为57.3%和50.1%;出水细菌含量低于《生活饮用水标准》(GB 5749—2006)的限值,细菌去除率大于99%。超滤组合工艺对藻类处理效果优于水厂工艺,藻类总去除率为99.3%。当膜通量下降时,缩短过滤时间、延长反冲洗时间可以使膜通量恢复;当超滤膜出现不可逆污染时,通过CIP清洗恢复膜过滤性能。在高藻水期,水温对膜通量和TMP影响较小,在保证出水水质的前提下,较大的膜通量运行更节能。     

冷轧废水深度处理系统工程设计及运行研究

某钢铁企业冷轧污水厂的出水满足《钢铁工业水污染物排放标准》(GB 13456—2012)标准,需要对该污水厂出水进行深度处理。深度处理系统设计采用“药剂软化+离子交换+超滤(UF)系统+反渗透(RO)系统”的工艺。运行过程中对深度处理系统进行优化,运行结果表明系统出水各项运行指标良好,达到设计标准,出水可回用于工艺循环冷却水补充水。系统处理费用约为3.73元/吨。     

双膜法应用于冶金中水回用工程实例

将超滤技术(UF)与反渗透技术(RO)相结合,对某铜冶炼厂中水进行深度处理,出水作为全厂工业循环冷却水系统补充水和锅炉给水使用。重点监测了超滤系统及反渗透系统的运行情况,连续3 a的运行结果表明,超滤系统运行稳定,出水水质优于反渗透进水要求;RO出水经后处理后,水质满足《循环冷却水用再生水水质标准》(HG/T 3923—2007)和《工业锅炉水质》(GB/T 1576—2008)。     

膜过滤技术应用:用超滤中空纤维膜处理饮用水

使用超滤 (UF)中空纤维膜通过试验室试验和中试试验验证了饮用水处理。研究了膜材料、工况以及原水质量对过滤性能的影响。发现醋酸纤维素 (CA)膜具有高而稳定的通量 ,并且当反冲洗压力两倍于过滤压力时通量增加更大。使用 50 m2 膜面积的大型 CA膜单元进行中试试验证实 UF系统完全可用作实际饮用水净化装置。膜过滤技术应用:用超滤中空纤维膜处理饮用水     

高矿化度煤层水用作生活饮用水的应用研究

在煤层气田开采过程中将排出大量伴生水,这种伴生水矿化度高、有机污染轻,需进行处理后才能够回用。在分析伴生水用作饮用水可行性的基础上,采用超滤—反渗透(UF—RO)工艺进行规模化处理,结果表明:膜系统运行稳定,UF作为RO进水预处理工艺,对CODMn去除率为29.94%、矿化度去除率9.55%、Cl-去除率8.33%。RO对污染物的去除效果显著,CODMn去除率为66.10%、矿化度去除率97.61%、Cl-去除率94.78%、NH3-N去除率72.94%。经GC-MS分析,系统出水基本不含有机物,水质达到《生活饮用水卫生标准》要求,吨水成本为4.03元。     

陶瓷膜处理地表水的工艺

采用混凝沉降与陶瓷膜超滤的组合工艺处理地表水,考察操作模式、膜孔径、膜构型以及膜通量等对膜过滤性能的影响。结果表明:在恒压操作下,终端过滤的操作压差应小于0.075 MPa,对于孔径大于50 nm的陶瓷膜而言,膜通量随孔径变化不大;错流过滤的膜通量随孔径增大而增大;错流过滤的渗透通量是终端过滤的1.5～2.2倍。恒通量操作下,蜂窝陶瓷膜过滤性能优于19通道陶瓷膜,并在恒通量150 L/(m2.h)下稳定运行。混凝沉降-陶瓷膜组合工艺对浊度的去除率大于99%,对吸收254 nm波长紫外线有机物(UV254)的去除率大于47.7%,产品水的部分指标优于GB 5749—2006中的指标。     

电镀废水处理及回用工程实例

采用混凝沉淀+水解酸化+膜生物反应器(MBR)+过滤+反渗透(RO)组合工艺,对某电镀企业生产废水进行深度处理和回用。首先通过混凝沉淀、生化和过滤去除重金属、有机物和悬浮物,然后利用RO系统去除剩余的有机物和盐分。实际运行结果表明,RO淡水水质可满足企业生产工艺用水水质要求,RO浓水水质达到了《电镀污染物排放标准》(GB 21900—2008)表2中的新建企业水污染物排放限值。     

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。