膜分离技术在吉林石化公司的应用

简要介绍了膜分离技术在吉林石化公司的应用．其中重点介绍了针对乙二醇装置的工艺特点，采用气体膜分离的先进技术回收工艺循环气排放中的乙烯，从而提高资源的利用效率，减少污染，实现清洁生产的情况，亦可为同类装置或其他需回收有机气体的装置提供参考．     

扬子石化运用膜分离技术实现乙烯回收

<正>膜分离回收乙烯技术近几年在国内乙二醇行业广泛运用,其基本原理是利用了特殊的高分子膜对乙烯优先透过性的特点,让乙烯、氩气、氮气的混合气在一定的压差推动下,经选择性透过膜,使混合气中的乙烯优先透过膜得以富集回收,而氮气、氩气等则被选择性地截留,从而达到分离的目的。扬子石化结合乙二醇联合装置运行实际,经过技术改造,新增一套膜分离回收乙烯单元,实现了有效回收乙二醇尾气中的乙烯成分,变废为宝。11月7日,随着膜回收单元进气阀的开启,扬子石化乙二醇装置的排放气源源不断进入膜回收单元,标志着     

气体分离膜应用的现状和未来

考虑了气体分离膜应用和气体传递机理的各种技术．现在商业气体分离膜应用的范围包括：富氮、富氧、氢回收、从天然气中除去酸性气体(CO2和H2S)、天然气脱水和有价值的挥发有机物(VOCs)的回收．讨论了每一个应用中可用膜材料的现状和限度，及有潜在力的若干新膜的应用，如乙烯／乙烷分离和燃料电池．     

膜法回收聚合尾气中氯乙烯

介绍了聚氯乙烯生产工艺及含氯乙烯尾气的产生及处理方法，同时阐述了有机蒸气分离膜的分离原理，并叙述了膜法氯乙烯回收装置在聚合尾气中回收氯乙烯的应用．     

兰州石化节能降耗增效取得实效

兰州石化公司（以下简称“公司”）相继建成了500万吨和550万吨两套常减压装置．45万吨和24万吨两套乙烯裂解装置。以及重整、汽油加氢、柴油加氢、延迟焦化、酮苯、锅炉等装置。这些大型装置均配备有工艺加热炉．加热炉消耗的能耗占装置消耗能耗总量的50％左右,公司目前投用的加热炉和锅炉每年消耗燃料气约80万吨。     

膜法回收氯甲烷装置一次开车成功

中科院大连化学物理研究所研发的氯甲烷有机蒸气膜法回收装置 ,日前在中石油吉化分公司 1 2万吨 /年有机硅生产线上一次开车成功 .运行结果表明 ,该装置工艺安排合理 ,操作安全可靠 ,各项运行参数达到了设计要求 ,原放空尾气中 90 %以上的氯甲烷得到了回收利用 .膜法有机蒸气分离技术是低能耗分离技术 ,能够满足现代工业尤其是石油化工领域对分离技术高效和无污染的发展要求 .大连化物所上世纪 90年代承担了中国科学院“八五”重大攻关项目———有机蒸气膜法分离技术 ,在国内率先研制出有机蒸气膜及其分离器 ,并在吉化公司乙烯分厂进行工业…     

用于气体分离的综合装置

通常，气体分离技术是独立开发的。例如，氮是在具有多级精馏塔的大型低温装置中以高纯度回收，或者可用吸收、吸附或膜扩散工艺以中等纯度回收。现在，空气产品和化学制品公司(宾夕法尼亚州，阿伦敦)正在开发一种将膜与深冷工艺结合的综合装置。空气产品公司A． P． Dyer说：“该综合装置在降低投资及操作费用上具有潜力。”     

杜邦公司开发氢回收装置

美国杜邦公司发明了氢回收用的薄膜分离装置。氢回收费用可削减至以往的25％，回收的氢可用于从硫含量高的原油中脱除硫及生产氨和甲醇等方面。预计，到八十年代末，这种分离装置的销售量按目前的价值计，将由5亿美元增至20亿美元以上。杜邦公司的装置曾在俄克拉何马炼油厂利用实验装置进行了一年多实验运转。     

有机蒸气膜在石油化工领域的应用

介绍了有机蒸气膜的结构和选择分离原理，重点阐述了有机蒸气膜在石油化工、天然气和石油炼制等工业领域的应用，并以MTR有机蒸气膜为例，结合实际的有机蒸气膜回收装置及有机蒸气回收方案，详细介绍了有机蒸气膜在有机蒸气回收方面的应用．     

技术创新在大庆石化改扩建工程中的应用

本文以大庆石化乙烯改扩建工程乙烯装置建设为例,概要介绍了自主研发的15万吨/年乙烯裂解炉、急冷系统计算模型、乙烯分离流程、系统集成方法等技术创新成果,为提升我国大型乙烯装置的建造水平提供了可借鉴性经验。     

化工尾气中氢气和乙烯的低温精馏回收工艺流程的设计与优化分析

化工尾气对环境污染严重,但是其中含有的氢气和乙烯具有较高的回收利用价值。针对某一化工尾气,采用低温液化精馏工艺对其中的氢气和乙烯进行分离。运用HYSYS软件进行化工尾气中氢气和乙烯低温精馏工艺流程的模拟与优化分析,给出了工艺流程中关键点的技术参数。分析结果显示,氢气和乙烯回收率达到90%。     

POE-g-MAH反应性增容HDPE/PA6共混合金的热致形状记忆性能

采用乙烯-辛烯共聚物接枝马来酸酐(POE-g-MAH)作为高密度聚乙烯(HDPE)/尼龙6(PA6)共混体系的反应性增容剂,通过熔融挤出制备出固定相具有物理交联结构的热致形状记忆合金。研究了组分含量,拉伸比和形变回复温度对合金的形变回复率和回复速率的影响。结果表明,POE-g-MAH的添加显著提高了共混合金的形状记忆性能,当组分配比为80/20/10(HDPE/PA6/POE-g-MAH),形变回复温度为135℃,拉伸比为75%时,试样形变回复率达到96.5%。     

Optical properties of fluorescent dye-doped-polymer thin film and its application to an optochemical sensor for quantification of atmospheric humidity

The humidity sensor used utilized a fluorescent dye entrapped within a poly(ethylene oxide) or poly(acrylic acid) matrix. The fluorescence intensity increased strongly and linearly with increasing humidity. The wavelength of the fluorescence maximum was 525 nm for the composite with poly(acrylic acid) over the whole range of the humidity. For the poly(ethylene oxide) composite, the fluorescence maximum in the lower humidity region was about 550 nm and it shifted to lower wavelengths with an increase in humidity. In both cases, the intensity of the fluorescence increased linearly with humidity. The 90% response and recovery time for humidity changes was less than 20s for the poly(ethylene oxide) composite, while a longer time was observed for the poly(acrylic acid) composite.     

Portable potentiostatic sensor integrated with neopterin-imprinted poly(ethylene-co-vinyl alcohol)-based electrode

Neopterin is a catabolic product of guanosine triphosphate, a purine nucleotide. Measuring neopterin concentrations in biological fluids such as urine provides information about cellular immune activation in humans under control of T helper cells. A high neopterin concentration in bodily fluids, including serum and urine, indicates cellular immunity activation, which is associated with oxidative stress. In this work, neopterin is the target molecule and imprinted onto poly(ethylene-co-vinyl alcohol) via solvent evaporation. The template molecules on the thin film are then removed, and the membrane is used as a sensing element for electrochemical urinalysis. Poly(ethylene-co-vinyl alcohol) containing 27?mol% ethylene had high imprinting effectiveness and may be integrated with the proposed portable biosensor. In random urine analysis, the cyclic voltammetry measurements of neopterin with an additional recovery method achieved >95% recovery for the neopterin concentration of 15?ng/mL.     

Determination of volatile and semivolatile mutagens in air using solid absorbents and supercritical fluid extraction

Volatile toxicants may be present in emissions from mobile and stationary sources as well as in ambient air. Methods for collecting and concentrating volatiles from air samples have been developed. Solid-phase adsorbents were compared in their trapping efficiencies for dichloromethane (DCM), ethylene dibromide (EDB), 4-nitroblphenyl (4-NB), 2-nitrofluorene (2-NF), and fluoranthene (FI). Charcoal and Carbosieve were the most efficient media for retaining DCM, while XAD-4 was the best adsorbent for EDB and the aromatic compounds. Extraction of direct spikes of compounds from adsorbents using supercritical carbon dioxide resulted in greater than 90% recovery of EDB and 60-92% recovery of the aromatics. Integration of trapping and desorption methods with the Salmonella microsuspension bioassay was demonstrated with EDB and 4-NB recoveries from air; chemical analysis and bioassay gave comparable results (within 10%).     

P(NIPAAm-PEGMA)接枝聚丙烯多孔膜表面的抗污染及自清洁性能

以等离子体引发方法制备了聚(N-异丙基丙烯酰胺-聚乙二醇甲基丙烯酸酯)(P(NIPAAm-PEGMA))接枝的聚丙烯(PP)多孔膜。考察了改性膜水通量及表面润湿的温敏性质,并研究了其表面抗牛血清白蛋白(BSA)污染及自清洁性能。结果表明,聚乙二醇(PEG)侧链引入后,P(NIPAAm-PEGMA)保留了体积相转变性质,并在低临界溶解温度(LCST)上下均能展现良好的表面亲水性。得益于表面亲水性的改善,改性膜在过滤BSA溶液时的通量衰减率降低至18.8%。经简单的变温水清洗,BSA污染膜的水通量恢复率可达98.2%,且表面甚少污染物残留。P(NIPAAm-PEGMA)接枝链的亲水性及体积相转变是实现改性膜表面自清洁的原因。     

Effects of type and dosages of organic depressants on pyrite floatability in microflotation system

Pyrite is considered as a disturbing sulfide mineral in the beneficiation of sulfide minerals and coal and in order to prevent floating of pyrite in the flotation, different inorganic, organic and biological depressants could be used. The most important organic pyrite depressants are starch, dextrin, guargum, carboxymethyl cellulose (CMC), ethylene diamine tetra acetic acid (EDTA), Diethylenetriamine (DETA). In this paper, flotation experiments were carried out by modified Halimond tube. At first, flotation experiments were performed to obtain optimal pyrite flotation condition (suitable collector and frother for maximum recovery). In optimal condition (collector: KAX?+?KIPX , 16?ppm; collector condition time: 4?min; frother: Poly Propylene Glycol (A65), 20?ppm; frother condition time: 30?s), pyrite recovery increased to 95.63%. Flotation kinetics experiments were performed and various kinetic models were evaluated on pyrite flotation. The results showed that flotation kinetics of pyrite is second-order. After obtaining optimal condition for flotation and kinetic studies, the effects of type and dosage of different organic depressants including starch, dextrin, guargum, carboxymethyl cellulose, EDTA and DETA at three concentrations (50, 100, 150?ppm) at neutral pH were comprehensively investigated. The results of the experiments showed that DETA can significantly reduce the recovery of pyrite at 150?ppm by 44%.     

Stable permanently hydrophilic protein-resistant thin-film coatings on poly(dimethylsiloxane) substrates by electrostatic self-assembly and chemical cross-linking

Poly(dimethylsiloxane) (PDMS) is a biomaterial that presents serious surface instability characterized by hydrophobicity recovery. Permanently hydrophilic PDMS surfaces were created using electrostatic self-assembly of polyethyleneimine and poly(acrylic acid) on top of a hydrolyzed poly(styrene-alt-maleic anhydride) base layer adsorbed on PDMS. Cross-linking of the polyelectrolyte multilayers (PEMS) by carbodiimide coupling and covalent attachment of poly(ethylene glycol) (PEG) chains to the PEMS produced stable, hydrophilic, protein-resistant coatings, which resisted hydrophobicity recovery in air. Attenuated total reflection Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the thin films had excellent chemical stability and resisted hydrophobicity recovery in air over 77 days of measurement. The spectra also showed a dense coverage for PEG dialdehyde and excellent resistance to protein adsorption from undiluted rat serum. Atomic force microscopy revealed dense coverage with PEG dialdehyde and PEG diamine. Contact angle measurements showed that all films were hydrophilic and that the PEG dialdehyde-topped thin film had a virtually constant contact angle (approximately 20 degrees ) over the five months of the study. Electrokinetic analysis of the coatings in microchannels always exposed to air also gave good protein separation and constant electroosmotic flow during the five months that the measurements were done. We expect that the stable, hydrophilic, protein-resistant thin-film coatings will be useful for many applications that require long-term surface stability.