催化剂形态对加氢脱硫滴流床反应器性能影响.docVIP

 催化剂形态对加氢脱硫滴流床反应器性能 影响 马倩，许闽，刘辉2** 5 10 15 20 25 30 35 40 （化工大学化工资源有限利用国家重点实验室，北京，100029； 摘要：采用数值模拟方法，建立了部分润湿的等温滴流床反应器模型，考察了具有相同体积 的不同形态催化剂颗粒（球、齿球、圆柱、三叶草、四叶草）对床层传递性质和加氢脱硫反 应性能的影响。结果表明，对于滴流床中的加氢脱硫，五种外形催化剂的液固传质影响均很 小，而气液传质影响均较大，尤其是在与静态液体接触区和与气体接触区，其中以四叶草催 化剂的气液传质影响最小、HDS 反应的效率最高、有效因子最大，其次是三叶草，而齿球 催化剂在五种催化剂中的颗粒直径最大，但其传质限制仅次于四叶草和三叶草，说明齿球外 形有利于减小传质限制。 关键词：滴流床；加氢脱硫；异形催化剂； 模型 中图分类号：TQ021.1 Simulation of An Isothermal Hydrodesulfurization Trickle-bed Reactor with Different Catalyst Particle Shapes MA Qian, XU Min, LIU Hui (State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029) Abstract: In this work the effect of different catalyst particle shapes (sphere, dentiform sphere, cylinder, 3-lobe, and 4-lobe) on the mass transfer characteristics, hydrodesulfurization (HDS) reaction was investigated in an isothermal and partial-wetting hydrodesulfurization trickle bed reactor by using the matlab numerical simulation method. The results show that 1) the liquid-solid mass limitations of five shape catalyst are all small, and the gas-liquid mass transfer limitations are significant, especially in contact areas around the static liquid zone and dry zone over the catalyst surface; 2) 4-lobe catalyst have the smallest gas-liquid mass transfer limitations, highest efficiency of HDS reaction and highest effectiveness factor, and then the 3-lobe catalyst; and 3) though tooth sphere catalyst has the biggest diameter of five catalysts, and its specific surface area is smaller than the 4-lobe and 3-lobe, it can reduce mass transfer limitations. ) Key words: Trickle-bed, hydrodesulfurization, catalyst shape, modeling 0 引言 在石油炼制工业，中等馏分油的加氢脱硫（HDS）通常采用气（氢气）、液（馏分油）、 固（固体催化剂颗粒）三相滴流床加氢脱硫反应器。传统的 HDS 过程所使用的催化剂都是 硫化的 CoMo/γ-Al2O3 和 NiMo/γ-Al2O3 催化剂，内扩散性质、压降限制、催化剂孔体积、催 化剂装填技术和催化剂活性等要求都将影响 HDS 催化剂外形的选择[1]。Cooper 等[2]研究了 催化剂颗粒形态和大小对不同加氢精制反应 NiMo 异形催化剂的影响，发现在选择 HDS 催 化剂时，要综合考虑催化剂颗粒的大小和形状；并指出，不可能选择一个最好的单一外形 的催化剂颗粒在所有加氢过程中都适用。Macias 和 Ancheyta