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31.
Yi‐Hung Chen Ching‐Yuan Chang Wei‐Ling Su Chun‐Yu Chiu Yue‐Hwa Yu Pen‐Chi Chiang Chiung‐Fen Chang Je‐Lueng Shie Chyow‐San Chiou Sally IM Chiang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(1):68-75
This study investigates the ozonation of CI Reactive Black 5 (RB5) by using the rotating packed bed (RPB) and completely stirred tank reactor (CSTR) as ozone contactors. The RPB, which provides high gravitational force by adjusting the rotational speed, was employed as a novel ozone contactor. The same ozone dosage was separately introduced into either the RPB or the CSTR for the investigation, while the experimental solution was continuously circulated within the apparatus consisting of the RPB and CSTR. The decolorization and mineralization efficiencies of RB5 in the course of ozonation are compared for these two methods. Moreover, the dissolved and off‐gas ozone concentrations were simultaneously monitored for the further analysis. As a result, the ozone mass transfer rate per unit volume of the RPB was significantly higher because of its higher mass transfer coefficient and gas–liquid concentration driving force. Furthermore, ozonation kinetics was found to be independent of the gravitational magnitude of an ozone gas–liquid contactor. Therefore, the results suggest employing RPBs as ozone‐contacting devices with the advantage of volume reduction. The experimental results, which can be used for further modeling of the ozonation process in the RPB, also show the requirement of correct design for the RPB. Consequently, the present study is useful for the understanding of practical application of RPBs. Copyright © 2004 Society of Chemical Industry 相似文献
32.
青岛市管道燃气公司在大尧罐站对低压16.5万m3干式气柜采用城市燃气直接置换,经合理确定置换范围,标准及过程,成功地进行了低压16.5万m3干式气相及其管道采用城市煤气直接置换的操作。 相似文献
33.
介绍抚顺石油化工公司石油一厂东蒸馏装置的改造情况,通过技术改造,使减压蒸馏塔由生产燃料型改造成生产石蜡-润滑油型,满足了该厂对石蜡和润滑油料的质量要求。 相似文献
34.
中国先进研究堆导流箱流场的数值模拟 总被引:1,自引:1,他引:0
采用目前国内普遍使用的计算流体力学 (CFD)软件PHOENICS 3 2对中国先进研究堆不同结构的导流箱的三维流场进行数值模拟计算。结果表明 :导流箱入口导流板和导流筒能显著改善导流箱入口冷却剂的流动状况 ,获得入口冷却剂沿周向均匀分流的效果 ,达到显著减缓入口冷却剂对垂直辐照孔道导管及安全棒导管直接的横向水力冲刷的设计目的 相似文献
35.
Cracking of petroleum vacuum residue (XVR) and its cocracking with plastics (PP or PS), Calotropis procera (CL) as a binary, ternary, and quaternary mixture of these individual plastics, and CL with XVR was carried out in a Perkin-Elmer thermogravimetric analyzer (TGA) for the purpose of comparing the process of the mixture with those of the individual components. Experiments were conducted at a heating rate of 40 K/min, in the temperature range of 30-900°C. Based on the results obtained, three temperature regimes were selected for studying the nonisothermal kinetics of TGA of individual XVR, plastics, and biomass as well as of the cocracking of these with XVR, i.e., below 400°C, between 400-500°C, and above 500°C. The kinetic studies were performed using the Coats and Redfern kinetic modeling equation. The overall activation energies obtained were 25 kJ/mole for petroleum vacuum residue, 99 kJ/mole for polypropylene, 21 kJ/mole for coal, and 35 kJ/mole for the mixture of all these materials. Thus, it has been found that there exists an overall synergy when three materials were coprocessed together. The overall orders and activation energies change during coprocessing of two or three different macromolecules, including mixed vacuum residue as presently observed. The detailed results that were obtained will be reported. 相似文献
36.
目前大型原油储罐逐步应用自动机械清洗系统进行清罐作业,而对于容量小、沉积物较少的油罐国内仍采用人工清洗方式进行。分析了油罐人工清洗作业过程时容易引发火灾的原因,并提出相应的预防火灾措施。 相似文献
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