反应器-催化剂颗粒双尺度分析费托合成的产物分布及其影响因素

发布时间：2019-03-13 13:27

【摘要】：在考虑产物液膜传质阻力的情况下,构建了反应器-催化剂颗粒双尺度费托合成产物分布的多场耦合数学模型,讨论了产物液膜及催化剂粒径对产物分布特性的影响。结果表明,产物碳原子选择性的计算结果符合费托合成经典的ASF分布。反应物浓度在催化剂颗粒表面处的浓度最高,沿着半径方向向中心处不断降低,而产物的浓度分布状态则正好相反。沿着流动方向,主体气流中反应物CO的浓度要高于催化剂内部平均值,产物C_(5+)浓度则与此相反;且浓度差异在反应器入口部分最为明显,随着反应不断进行,催化剂颗粒内外组分的浓度差异逐渐缩小。此外,催化剂粒径越大,颗粒内部组分的浓度差也越大,而减小粒径可以降低液态产物传质阻力,同时有效避免催化剂的"死区"现象,有利于提高其利用效率。
[Abstract]:Considering the mass transfer resistance of product liquid membrane, a multi-field coupling mathematical model for product distribution of reactor-catalyst particle two-scale Feto synthesis was established. The effects of product liquid membrane and catalyst particle size on product distribution were discussed. The results show that the calculated results of carbon atom selectivity are in agreement with the classical ASF distribution of Fischer-Tropsch synthesis. The concentration of reactants is the highest on the surface of catalyst particles and decreases continuously along the radius direction, while the concentration distribution state of the product is just the opposite. Along the flow direction, the concentration of reactant CO in the main gas flow is higher than the internal average value of the catalyst, and the concentration of product C5 is opposite. The concentration difference was most obvious in the inlet part of the reactor. With the continuous reaction, the concentration difference between the inside and outside components of the catalyst particles decreased gradually. In addition, the larger the particle size of the catalyst, the greater the concentration difference of the components in the particle, and the decrease of the particle size can reduce the mass transfer resistance of the liquid product, and effectively avoid the "dead zone" phenomenon of the catalyst, which is beneficial to the improvement of the utilization efficiency of the catalyst.
【作者单位】：华东理工大学机械与动力工程学院;
【基金】：中央高校基本科研业务费探索基金项目(WG1414044)资助
【分类号】：O643.36;TQ529.2

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