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991.
催化干气的利用   总被引:1,自引:0,他引:1  
炼厂气含C_1~C_4组份,未被回收利用。催化裂化干气中含乙烯10%~20%,氢50%~70%。采用膜分离技术从重油催化裂化干气中回收氢气,制氢成本低,能源利用合理;介绍了从催化裂化干气中回收乙烯的方法及乙苯的利用。指出炼油厂采用膜分离技术回收氢及用催化裂化干气中的乙烯生产苯乙烯,是合理利用石油副产物的有效途径。  相似文献   
992.
This paper reports on the experimental investigation carried out to evaluate fractional dispersed phase holdup for a gas‐liquid mixture in a modified multi‐stage bubble column (with contraction and expansion disks), which has been conceived, designed and fabricated as a wet scrubber for control of air pollution; in addition it has versatile use as a gas‐liquid contactor in chemical process industries. A correlation developed for predicting fractional dispersed phase holdup has been found to be encouraging and highly significant from statistical analysis.  相似文献   
993.
The fifth abdominal segment of femaleEriocrania semipurpurella (Stephens) andE. sangii (Wood) contains a pair of exocrine glands. Hexane extracts of this segment were prepared from both species and analyzed by gas chromatography with simultaneous flame ionization and electroantennographic detection (EAD). For both species, the EAD active peaks were identified as nonan-2-one, (Z)-6-nonen-2-one, and (Z)-6-nonen-2-ol by means of mass spectrometry and comparison of retention indices with those of synthetic standards. Enantiomeric separation of chiral alcohols from the female extracts was achieved by gas chromatographic analysis on a cyclodextrin column. InE. semipurpurella, a mixture of (2S,6Z)-nonen-2-ol and (2R,6Z)-nonen-2-ol (2: I) was found, whereas inE. sangii (2S,6Z)-nonen-2-ol was the predominant enantiomer and only traces of theR enantiomer were indicated by the antennal response. In field tests, a blend of the three compounds was not attractive to conspecific males. A subtractive assay showed that the alcohol in various enantiomeric mixtures was the only attractive compound, whereas addition of (Z)-6-nonen-2-one to the alcohol completely inhibited the attraction of both species. A trapping experiment including a wide range of ratios between theR andS enantiomers showed that baits containing 95–100% of theS enantiomer were attractive to maleE. sangii, whereas males ofE. semipurpurella were attracted to all tested ratios of the enantiomers. However, the response profiles of maleE. semipurpurella differed between populations from southern Sweden, south Finland, and the Kola Peninsula in Russia. In south Sweden males were maximally attracted to a racemic mixture of the alcohols. At the Kola PeninsulaE. semipurpurella was attracted to baits containing 95–100% of theR enantiomer. In south Finland all tested ratios between 0 and 100%R enantiomer trappedE. semipurpurella, but the trap catches appeared to be bimodally distributed with peaks around 15 and 70%R enantiomer. The trapping results suggest the existence of pheromone races or sibling species among the specimens identified asE. semipurpurella.Dedicated to Prof. H. J. Bestmann on the occasion of his 70th birthday.  相似文献   
994.
气化炉油气掺烧技术探讨   总被引:1,自引:0,他引:1  
毛爱国 《大氮肥》2003,26(4):250-253
简要叙述了九江合成氨装置五通道气化烧嘴掺烧干气试验过程,实践证明渣油掺烧干气工艺是可行的。通过对掺烧干气试验结果的理论分析,渣油雾滴的减小和雾化角的减小。使燃烧区上移,在保证渣油充分燃烧的前提下,减少火焰对气化炉壁的冲蚀,会有效增加装置运行周期。  相似文献   
995.
尹云省  胡才平  陈德黔  李毅 《贵州化工》2003,28(6):29-30,34
介绍WLSP852微量硫分析仪成功取代陈旧的汞量法用于原料气硫分析。不仅能准确分析进口管线、气液离器、加氢转化炉等位号硫的总含量,还能分别测定各种形态硫的含量。  相似文献   
996.
壳牌煤气化配套硫回收工艺方案的选择   总被引:2,自引:0,他引:2  
裴兴社 《化肥设计》2003,41(5):16-18
对壳牌煤气化合成气处理技术进行了分析,总结了从粗煤气中脱除的酸性气的特点。对硫回收技术的8种工艺方案从H2S浓度要求、生产能力、环保、投资和运行费用方面进行了对比,指出了壳牌煤气化硫回收工艺方案的选择要领。  相似文献   
997.
干气密封的工作机理及其典型结构   总被引:6,自引:0,他引:6  
详细叙述了干气密封的结构、工作原理 ,并介绍了其使用和维护要点  相似文献   
998.
喷雾干燥在环保领域中的应用   总被引:5,自引:0,他引:5  
环境保护是我国的基本国策之一,近年来呈蓬勃发展之势.本文主要介绍了喷雾干燥在半干法烟气脱硫、味精废水综合利用、造纸黑液处理等环保领域内的广泛应用.  相似文献   
999.
气液两相机械搅拌釜中翼型组合桨持气特性   总被引:4,自引:0,他引:4  
研究了机械搅拌釜中翼型组合桨的组合方式、桨间距、通气位置及翼型桨的排出流方向对气含率的影响。在单位体积功率消耗相同的情况下,采用以翼型k5桨为下层桨、较低的通气位置及较大的桨间距为搅拌釜的几何结构,并采用翼型桨的排出流方向向上的搅拌方式,可以提高搅拌釜的气含率。给出了气含率与单位体积功耗和表面气速的关联式。  相似文献   
1000.
Epoxidized natural rubbers (ENR‐25 and ENR‐45) were prepared using the performic epoxidation method. Two‐component (ENR–cassava starch) and three‐component (ENR–NR–cassava starch) blends were prepared. ENR‐25 and ENR‐45 were blended with various quantities of gelatinized cassava starch in the latex state. The pure ENR exhibited lower shear stress and shear viscosity than those of the blends with cassava starch. Furthermore, the shear stress and shear viscosity were increased with an increase in the cassava starch concentration. The chemical interaction between the epoxide groups in the ENR and the hydroxyl groups in the cassava starch molecules might be the reason for the increasing trends of the shear stress and shear viscosity. The blends are classified as compatible blends because of the strong chemical bonding between different phases. SEM micrographs were used to clarify the compatibility. Power law behavior with pluglike flow profiles was observed for all sets of ENR–NR–cassava starch blends. Very low power law index values (<0.34) and highly pseudoplastic fluid behavior were also observed. The log additive rule was applied to plots of zero shear viscosity (consistency index) and the shear viscosity versus the concentration of ENR‐25. Positive deviation blending was observed, which indicates compatible blends. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1752–1762, 2004  相似文献   
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