湍动流化床内相间传质系数的测定

本实验在φ２００ｍｍ的流化床中，以ＦＣＣ粒子作为流化颗粒，采用示踪气与流化气从床底分相并流输入的示踪方式，并利用气相色谱仪中的热导池对流化床内的示踪气进行连续取样分析，测定了湍动流化床内不同表观气速下的相间传质系数。实验结果表明相间传质系数随轴向位置的变化较大而随径向位置的变化较小，且其值随表观气达的增大而增大。

The Measurement of the Mass Transfer Coefficient in Turbulent Fluidized Bed

Using FCC as the fluidized particle,the experiment was conducted in a fluidized bed whosediameter is 200mm.The traced method is that the tracer gas and fluidized gas parallerly enter the flu idized bed from the bottom.The bed's tracer was measured continuously though the thermal conduc tivity detector of gas chromatograph. According to these methods.the bubble-emulsionmass transfercoefficient of turbulent fluidized bed has been measured under different superficial gas velocities.Theresults have shown that the change of coefficient is big with the change of axial location, but compara tively small with the change of radial location. Furthermore,the coefficient increases when the superficial gas velocity increases.'