管式填料床反应器内的湍流微观混合研究

Study on Turbulent Micromixing in a Tubular Packed Bed Reactor

采用碘化物-碘酸盐平行竞争反应体系研究了管式填料床反应器内的湍流微观混合。通过沿程取样分析来考察离集指数(XS)沿反应器轴向位置的分布。实验结果表明,反应物在管式填料床反应器内的离集主要发生在反应物开始相遇的区域且随着流速的增加离集状况得到明显改善。在实验基础上,采用团聚(Incorporation)模型计算得到管式填料床反应器的微观混合时间tm在1×10?3s到4×10?3s之间,明显小于搅拌槽反应器内的微观混合时间。相对于搅拌槽反应器,管式填料床反应器更适合于快速反应。同时研究表明,丝网填料的加入能提高微观混合效率。

The turbulent micromixing in a tubular packed bed reactor was studied via using the parallel competing reaction system iodide-iodate reaction system. Distribution of segregation index （Xs） in the reactor was studied through sampling along the axial positions. The experimental results indicate that the segregation of the reagents in the reactor mainly appeares in the initial contacting region and is improved with the increase of liquid flux. Based on the experimental results and the incorporation model, the micromixing time in tubular packed bed reactor was estimated as 0.001-0.004s, which is much shorter than that in tank reactor and it can be therefore concluded that the tubular packed bed reactor may suit rapid reactions better. It is also illustrated by present study that the installation of the wired packing could enhance the micromixing process and improve the micromixing efficiency apparently.