芳烃抽提工艺流程的模拟与优化

采用SIMSCI公司开发的流程模拟软件PRO/Ⅱ对实际生产中预分离塔、抽提精馏塔、溶剂回收塔、苯塔、甲苯、二甲苯塔进行逐塔模拟并优化,进而对全流程进行模拟,给出了模拟结果,最终获得最佳的工艺操作参数,所得产品符合国家质量要求。     

芳烃抽提装置节能优化改造

针对芳烃抽提装置溶剂比大、能耗高的现状,芳烃抽提优化改造以提高抽提塔的塔盘效率,降低溶剂比为切入点,采用新型高效塔盘技术对抽提塔、回收塔实施优化改造,改造后装置运行平稳,抽提塔的溶剂比由3．49降至2．3,回收塔回流比由0．325降至0．18,装置节约2．0MPa蒸汽约3t／h,全年折合标准燃料油2217t,效益明显。     

芳烃抽提装置芳烃分离模拟及设计优化

采用PRO/Ⅱ流程模拟软件对某新建项目40万t/a芳烃抽提装置，混合芳烃中苯、甲苯、二甲苯（BTX）分离进行常规双塔精馏和双塔差压热耦合精馏进行稳态模拟，在产品质量规定要求下，分别对苯塔和甲苯塔进行设计优化，对比不同分离方案用能要求及能耗，旨在工厂公用工程条件限制下，选择最合适的分离工艺，提高低温热利用效率，达到最佳节能降耗的效果。     

400万吨/年常减压装置降能改造研究设计

对于某炼厂常减压装置由于原油变化带来的能耗高问题,采用炼油工艺模拟软件PRO/II,建立换热网络模型。根据调整后的原油评价数据,初馏塔、加热炉、常压塔、减压塔操作参数以及产品馏分分布的要求作为装置降能改造设计的基础输入参数,以流程模拟软件计算的结果为设计依据,按照施工周期短、设备变动小、改造投资少的原则对现有换热网络进行改造设计。通过装置投产后的标定数据,对设计值进行校核,结果显示模拟结果与生产数据基本一致。常减压装置换热终温提高了15℃,综合能耗由原来的11.50 kg EO/t降低到9.554 kg EO/t标准油。     

高效塔内件在重苯提萘精馏装置扩产改造中的应用

采用耐堵浮阀塔盘与高效填料塔内件,优化调整双效热耦合精馏流程改造重苯提萘精馏装置,使重苯原料处理量由2万t/a扩产至4万t/a,工业萘产品结晶点由原来的72℃提高至76.5℃以上,副产工业甲基萘产品,降低了生产能耗,提高产品质量,稳定了系统操作。     

酸性水汽提塔由直接蒸汽汽提改造为重沸器间接汽提的设计

为减少进污水处理场的水量并回收凝结水,对25t/h酸性水汽提装置进行改造,将酸性水汽提塔由直接蒸汽汽提改造为重沸器间接汽提。改造后运行平稳,去污水处理场的净化水中H2S含量10ppm、NH3含量为70.1ppm,流量由19.75t/h降低到15.55t/h,装置能耗由643.79MJ/t原料降低到610.38MJ/t原料,各项指标均达到设计要求。     

气体分馏装置脱丙烷塔的流程模拟

以某石化公司300kt/a气体分馏装置中脱丙烷塔为研究对象,运用流程模拟软件PRO/Ⅱ进行稳态模拟,使脱丙烷塔在产品质量符合要求的条件下,塔的操作参数最佳,塔的能耗值达到最小.综合考虑各关键影响因素,采用流程模拟软件PRO/Ⅱ的灵敏度分析方法,对该塔进行模拟分析,并对分析的结果进行总结和讨论.     

丁二烯抽提装置乙腈精制再生技术开发

开发了一种新的乙腈精制再生技术,适用于乙腈法丁二烯抽提装置,新工艺在原有水洗回收流程基础上加入变压精馏,可将再生乙腈纯度(质量分数)由80%提高到95%,同时脱除乙腈中重组分和氨等杂质。采用ASPEN流程模拟,确定乙腈变压精馏各塔的工艺参数和设备参数。该技术连续精制再生能力为30 kt/a,装置综合能耗(标油)59.36 kg/t产品乙腈,每吨产品乙腈再生操作费用150元;装置批量再生费用7.5万元,再生周期6 d。     

改进纯苯塔生产操作经验

1 存在问题 我厂的精苯装置是以粗苯和轻苯为原料,装置的处理能力为1万t/a,由两苯塔、初馏塔、吹苯塔、纯苯塔、甲苯塔和二甲苯塔组成,采用全连续精馏工艺生产纯苯、甲苯和二甲苯产品.几年来,精苯装置的运行情况良好,产品质量稳定,只是纯苯塔的运行情况不很稳定,特别是该塔在开工时的调整周期长,一般需经30h左右调整才能生产出合格的产品,操作条件稍有变化,立即影响纯苯的质量,甚至出现不合格品,成为整个装置的生产瓶颈.     

利用导向喷射塔盘改造两苯塔

应用导向喷射塔盘对两苯塔进行技术改造,取得了良好的效果。导向喷射塔盘可在塔径不变的情况下,通过改造塔盘达到提高生产能力的目的,充分体现导向喷射塔盘通量和处理能力大的特点。导向喷射塔盘效率高,可提高产品收率和降低能耗。改造后,粗苯处理能力提高,能够满足新增粗苯的加工要求,轻苯收率提高2%,产量增加200t/a,并节省蒸汽29%。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。