运用欧拉双流体模型对新型短接触旋流反应器内气、固两相流场进行了数值模拟,考察了操作参数和颗粒直径对反应器内颗粒流动分布的影响.结果表明,操作气速大于基准条件会降低反应器混合腔内的气-固接触效果,而在不影响流化状态的情况下适当增大催化剂的质量循环流率对催化剂的均匀分布有利.在基准操作条件下,5和30 μm粒径颗粒在反应器内的浓度分布梯度较大、均匀性较差,并且5μm颗粒与反应产物的分离也不彻底.因此,催化剂宜选用平均粒径为10 μm左右的颗粒,既可以强化接触效果,也不会出现返混夹带现象,保证后续工艺流程的顺利进行.催化剂颗粒是否均匀分布是影响反应收率的最主要因素之一,本研究结果为短接触旋流反应器的工业应用及性能改进提供了重要的理论参考依据.%Gas-solid two-phase flow in quick-contact cyclone reactor was simulated with the Eulerian model. The effects of operation parameters and particle diameter on particle flow distribution in quick-contact cyclone reactor were researched. The results showed that, to some extent, decrement of gas velocity had a disadvantageous effect on gas-solid contact in the mixing cavity, and increment of quality circulation flow rate of catalyst reasonably was good for uniform distribution under the condition that the fluidized state was normal. The solid concentration gradient was higher for the particles with diameter of 5 μm and 30 μm under the reference operation condition, and the solid distribution was very non-uniform, and the gas-solid separation for 5 μm particles was not complete. The appropriate particle diameter was 10 μm in the three particle diameters of 5, 10, 30 μm. As the catalyst of 10 μm diameter was used in quick-contact cyclone reactor, not only the effect of gas-solid contact could be strengthened, but also the backmixing of solid flow could be restrained, which ensured the following operation to go on smoothly. The distribution condition about catalyst particles was one of the most important factors affecting the reaction yield, so that the research results could provide the theoretical basis for industrial application and performance improvement of the new reactor.
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