国内外乙二醇生产技术及市场分析(下)

介绍了乙二醇的生产技术，分析了国内外乙二醇的生产消费现状及市场前景，提出了发展我国乙二醇生产的一些建议。     

Determination of ethylene oxide content inn-Alcohol ethoxylates by proton nuclear magnetic resonance spectroscopy

Proton Fourier transform nuclear magnetic resonance spectral data were collected onn-alcohol ethoxylates and used to calculate the percent ethylene oxide (EO) content of then-alcohol ethoxylate without an internal or external standard. The accuracy and precision of the method were determined from ten repetitive analyses of hexaethylene glycol monon-dodecyl ether. The standard deviation was 0.23 wt% EO with a relative standard deviation of 0.40%. The method had a relative error of +0.55% and an absolute error of +0.32% EO. This paper was presented at the 20th ISF World Congress/83rd AOCS Annual Meeting and Exposition in Toronto, Canada, May 10–14, 1992.     

乙烯装置微机优化系统

介绍乙烯装置上实现的一种计算机生产优化系统．该系统在操作经验的记忆、对比和推理的基础上对生产过程进行优化．为复杂工艺过程的优化控制提供了一条新的可行途径。     

联氨还原金属的应用研究

研究了联氨作为强还原剂在化学镀、金属回收和废水处理中的应用,并指出了使用联氨应注意安全。     

乙烯装置先进控制系统应用及其效益

介绍了抚顺乙烯装置在８０年代由美国ＡＢＢＳＩＭＣＯＮ公司引进的裂解炉先进控制系统（ＡｄｖａｎｃｅｄＰｒｏｃｅｓＣｏｎｔｒｏｌ，ＡＰＣ）。在对其深入研究基础上，结合抚顺乙烯裂解炉具体特点，修改了国外软件组态错误，重新设计了主联锁逻辑，完善了控制策略，增加了操作画面，开发了先进控制实时管理功能。该系统１９９５年在抚顺乙烯完成了调试与投用工作。ＡＰＣ运行以来，裂解炉控制质量和装置效益得到明显提高。该项技术在石化行业具有较好的实用性     

Real-time monitoring of hemicellulose liquefaction in ethylene glycol

Xylan was used as a model material to study the liquefaction of hemicellulose in the presence of ethylene glycol. The ReactIR^TM reaction analysis system was used to monitor the entire liquefaction process online. The results showed that xylan was decomposed and transferred to liquid phase. The gel permeation chromatography results of the liquid products showed that the weight average molecular of xylan decreased signi?cantly to around 1728 g/mol after liquefaction. Gas chromatography-mass spectrometry revealed that the ethylene glycol liquefaction products from xylan include ethylene glycol and its derivatives, alcohols, aldehydes, ketones, some acids and their esters.     

1200kt/a乙烯改扩建工程管网改造项目方案探讨

1200kt/a乙烯改扩建工程是大庆石化公司"十一五"发展的重点工程。文中以该工程的工艺及热力管网改造项目为例,从工程概况、材料计划、施工方案编制、过程经营、成本控制、风险防范等方面,探讨了管网改造项目的实施方案。     

Morphology,mechanical, and rheological behavior of microcellular injection molded EVA–clay nanocomposites

Ethylene vinyl acetate (EVA)/montmorillonite (MMT) nanocomposites diluted from master batch (50 wt.%) with EVA and EVAgMA was used in this study. The organoclay EVA nanocomposites were then injection molded by conventional and microcellular methods. Nitrogen was used as the blowing agent. The effect of organoclay content and MA grafted EVA on the morphology and the mechanical and rheological properties of the EVA–clay nanocomposites were then investigated. The results showed that the mechanical properties (tensile and impact) increased as the clay content increased. Cell size decreased as the clay loading increased. The EVAgMA nanocomposites had better mechanical properties than the EVA nanocomposites. XRD results showed that the EVAgMA nanocomposites have an exfoliated layered structure while the EVA nanocomposites are intercalated. Rheological results showed the viscosity is clay loading dependent and that the shear thinning effect occurs at high shear rates.     

Emission Source Characterization during an Ethylene Plant Shutdown

To conduct a well‐planned plant shutdown, so as to reduce flare emissions for the sake of plant profitability and local environmental sustainability, one of the primary tasks is to perform comprehensive and precise accountings for flare emissions. Since the literature is still lacking systematic and quantitative studies, plant‐wide dynamic simulations are employed to simulate an ethylene plant shutdown and characterize its flare emission sources through which dynamic emission profiles of various emission species changing with respect to time are obtained. Plant shutdown emission inventories are enriched with details for point emission sources, and possible technical supports are provided to both industry and environmental agencies on evaluating and developing cost‐effective flare minimization strategies in the future.     

Key factors affecting nickel recovery during the segregation of laterite ores

The segregation process as applied to nickel laterite ores involves the formation of gaseous nickel and iron chlorides which are subsequently reduced to form ferronickel on the surface of a solid carbon reductant. A fundamental study of the process has been carried out using limonite, nontronite and garnierite ores. The study highlighted the significant impacts that ore mineralogy and carbon addition have on the amount of nickel which is segregated rather than retained within the ore due to in situ reduction. These important aspects affecting nickel recovery and the success of the process are discussed in this paper.