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81.
DJ—3新型塔盘在催化重整脱水塔中的应用 总被引:1,自引:0,他引:1
对新型DJ-3复合塔盘的性能进行了简介,简述了重整蒸馏脱水过程及特点,重点突出蒸馏脱水塔的扩能改造,总结了DJ-3复合塔盘的工业应用及生产标定情况。 相似文献
82.
通过对板式塔流体力学性能的分析,找出了板式塔塔板结构参数对负荷性能图中负荷性能曲线的影响关系,可用于指导板式塔的优化设计和改造。 相似文献
83.
Using TiO2 as carrier, CuO/TiO2 catalysts with different CuO loading were prepared by the impregnation method. The catalytic activities in NO+CO reaction
were examined with a micro-reactor gas chromatography reaction system and the methods of TPR, XPS and NO-TPD. It was found
that the catalytic activities were affected by pretreatment atmosphere, i.e. H2 atmosphere > reduction–reoxidation > 10%CO/He > reaction gas (fresh sample). NO decomposition was better by low-valence Cu
species than by high-valence Cu species, i.e. Cu0>Cu+>Cu2+. The XPS results indicated that Cu species on CuO/TiO2 were Cu0, Cu+, normal Cu2+(Cu2+(I)) and chain-structured Cu2+(Cu2+(II)) as –Cu–O–Ti–O–. The activities of Cu2+(II) were much higher than that of Cu2+(I), but both species were very unstable in the reaction atmosphere and easily reduced by CO, which accounted for the variable
activities of fresh catalysts with increasing reaction temperature. In NO+CO reaction, the redox process was a cycle of Cu+–Cu2+(I) at low reaction temperature but was a cycle of Cu0–Cu+ at high reaction temperature. As shown by NO-TPD, high catalytic activities could be attributed to the following factors,
e.g. oxygen caves on the catalyst’s surface after pretreatment with H2 and reduction–reoxidation, formation of Cu0 after pretreatment with H2, and increment of Cu species dispersion and formation of Cu2+(II) after pretreatment with reduction–reoxidation. 相似文献
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Reactive distillations for the production of ethyl acetate (EtAc) and isopropyl acetate (IPAc) are classified as the type-II process where the first column consists of a reactive zone and a rectifying section followed by a stripper [Tang et al., 2005. Design of reactive distillations for acetic acid esterification with different alcohols. A.I.Ch.E. Journal 51, 1683-1699]. Instead of using pure alcohols and acetic acid as reactants, this paper studies the effects of reactant purity on the design and control of reactive distillation. This offers significant economical incentives (by reducing raw materials costs), because ethanol forms an azeotrope with water at 90 mol% and isopropanol/water has an azeotrope at 68%. The purities of the acid is set to 95% for acetic acid (industrial grade), 87% for ethanol, and 65% for isopropanol. The results show that the total annual costs (TAC) increase by a factor of 5% for EtAc and 8% for IPAc production using reactive distillation. Next, the operability of the reactive distillations with azeotrope feeds is explored. Three disturbances, feed flow, acid feed purity, and alcohol feed composition, are introduced to assess control performance using dual-temperature control and one-temperature-one-composition control. Simulation results indicate good control performance can be achieved for reactive distillation with azeotropic feeds. 相似文献
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A simple method has been developed to optimally design a distillation sequence with a fixed degree of flexibility in feed composition and flowrate, and accounts for uncertainty in stage efficiency, K-value and beat transfer coefficient calculations. The method minimizes a weighted cost function and ensures both optimal and feasible operation in the range of flexibility/uncertainty by using an approach termed “practical feasibility”. The method was tested on a 4 column distillation sequence separating a 5 component light alkane feed mixture. Results are presented to illustrate the effect of uncertainty on sequence cost and column overdesign. 相似文献
90.
气—液鼓泡塔中流动域和气含率的分布 总被引:1,自引:0,他引:1
利用压力传感器测定了气、液两相鼓泡塔内不同轴、径向位置上压强的脉动信号,分析了压强的脉动特征,计算了各种操作条件下塔内不同轴向位置截面上的平均气含率,发现在不同操作条件下,塔内可能出现不同的流动域分布,即全塔均匀鼓泡域、全塔过渡域、全塔湍动鼓泡域以及均匀鼓泡域,过渡域和湍动鼓泡域中的相邻2种或3种流域同时出现在塔内不同高度上。提出了不同轴向位置流域转变的判据。并发现,同一截面的不同径向位置基本处于同一流域内。同时研究了鼓泡塔内气含率在轴向上的分布规律,给出了不同流动域内气含率的关系式。 相似文献