低温甲醇洗工艺的技术优化

介绍了低温甲醇洗工艺流程设置及特点,结合项目的实际情况对低温甲醇洗工艺进行了优化调整,在确保技术可靠、操作稳定的基础上,进一步优化装置能耗、降低操作费用、缩减装置投资,并为同等规模低温甲醇洗流程设置提供参考。     

隔壁共沸精馏塔分离异丙醇水溶液的模拟

提出一种单塔共沸精馏生产无水异丙醇的新工艺流程,即采用隔壁塔替代常规共沸精馏流程中的脱水塔及提浓塔。应用Aspen Plus模拟软件,对隔壁共沸精馏塔流程及常规共沸精馏流程进行了模拟,比较了两种流程的液相组成、温度、汽液相流量及能耗,结果显示新工艺流程可以节省能耗14.6%,并能降低设备投资费用和操作费用。其模拟结果还需试验进一步验证。     

用共沸精馏隔壁塔生产无水乙醇的研究

提出1种单塔共沸精馏生产无水乙醇的新工艺流程,即采用隔壁塔替代常规共沸精馏流程中的脱水塔及提浓塔.应用ASPEN PLUS模拟软件,对新工艺流程及常规共沸精馏流程进行了模拟,并对2种工艺流程作了对比,结果显示新工艺流程可以节省能耗28.2%,并能降低设备投资费用和操作费用.     

催化重整再接触方案对比

催化重整装置设置再接触可以充分回收含氢气体中的轻烃(主要为液化石油气组分),提高重整产氢纯度和液体收率。本文通过对三种再接触流程,即稳定塔顶燃料气无返回的单段再接触流程、稳定塔顶燃料气返回的单段再接触流程和逆流两段再接触流程的模拟计算,比较了不同再接触流程的产品收益、投资和能耗,得出了不同再接触流程的适用性,为再接触工艺流程的选择及优化提供依据。     

有机硅单体分离系统工艺流程模拟分析

介绍了有机硅单体分离系统的3种工艺流程,即顺式切割的10塔流程、反式切割的10塔流程和7塔流程.并采用化工过程模拟软件Aspen Plus进行了模拟计算,对3种工艺流程的能耗做了详细对比,结果表明:10塔流程在能耗和主产品二甲基二氯硅烷的收率方面均优于7塔流程.两种lO塔流程各有优劣,顺式切割的10塔流程与反式切割的10塔流程的产品纯度相当,而能耗较低,但设备投资较大.     

用隔壁式反应精馏塔技术水解乙酸甲酯的模拟研究

提出1种单塔催化水解乙酸甲酯的新工艺流程,即采用隔壁式反应精馏塔替代常规反应精馏流程中的反应精馏塔及甲醇精馏塔.应用Aspen Plus模拟软件,对新工艺流程及常规反应精馏流程进行了模拟,考察水酯进料摩尔比、回流比、水酯进料位置及气相分配比等因素对新工艺的影响,并对2种工艺作了对比,结果显示新工艺流程可以节省再沸器能耗19.6%,并能降低设备投资费用和操作费用.     

Linde与Lurgi低温甲醇洗工艺流程分析

介绍了Linde公司和Lurgi公司的低温甲醇洗工艺流程特点,并比较了两种工艺流程的异同点,虽然两种低温甲醇洗流程总体设置情况及工艺技术指标值相差不大,但在流程的细节设置上各有特点,导致两种流程的投资、消耗等略有差异。     

乙酸甲酯催化反应隔板塔的设计

研究了催化反应隔板塔生产乙酸甲酯的工艺流程,用固体酸催化剂代替传统的硫酸催化剂,把反应位置固定在反应精馏塔的中部。该工艺既提高了反应转化率与选择性又降低了设备的腐蚀,同时消除了含酸废水的处理工艺,节省了投资费用。分析了工艺流程与相平衡的定性关系,论证了工艺的可行性。运用Aspen Plus流程模拟软件对过程进行了稳态模拟,重点考察了气相分配比对产品质量分数和再沸器负荷的影响。以年总费用作为目标函数,对流程进行了经济优化。对新工艺流程和传统的工艺流程做了比较,结果表明,新流程可以节省再沸器能耗7.7%和设备费用15.53%。     

低温甲醇洗配套丙烯冷冻站的工艺设计

介绍低温甲醇洗配套的丙烯冷冻站设计的基本原理,用ASPEN PLUS软件进行流程模拟计算,设计工艺流程。分析流程模拟的特点及需要注意的问题,并说明关键设备的选型。     

不同净化工艺下氧气纯度对合成氨流程能耗的影响

对于配备纯氧气化的合成氨工艺流程来说,空分单元的能耗巨大,具有较大节能潜力。如果适当降低氧气纯度,可以有效降低整个合成氨流程的能耗。同时,由于流率增大使得后续净化单元的操作费用有所增加,这样就存在一个整个流程能耗最低的最优纯度。研究应用Aspen Plus软件对甲烷化精制工艺下的工业合成氨全流程进行模拟并与液氮洗精制工艺进行了全面对比分析,着重考虑了空分所产氧气的纯度对于整个系统的影响。结果表明,氧气纯度的变化对净化工段的能耗有一定影响,两种净化流程所得能耗与氧气纯度的关系曲线走势十分相似。通过能耗与操作费用的对比,确定了92%氧气纯度的液氮洗工艺流程是合成氨的最优方案,对实际生产有一定指导作用。     

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。