鼓泡塔中气泡尺寸分布和局部气含率研究

Study on bubble size distribution and local gas holdup in bubble column

在内径为0.38 m的鼓泡塔中采用双电导探针法对不同通气速率下的气泡尺寸分布和局部气含率进行了实验研究,分析了气泡尺寸的概率密度分布。结果表明:气泡尺寸随轴向高度的增加而增大,随径向距离增加而减小;鼓泡塔中气液流动可分为过渡流域和充分发展流域,在过渡流域气含率随轴向高度增加而增大,在充分发展流域气含率趋于均值,径向局部气含率分布呈抛物线型下降。高气速下气泡尺寸概率密度分布比低气速下宽,且随轴向高度的增加分布变宽。

The bubble size distribution and local gas holdup in a bubble column with inner diameter of 0.38 m were measured with dual conductivities probes, and the probability density distribution of bubble size was calculated. The result shows that bubble size increases with the increase of axial height and decreases with the increase of radial distance. Flow pattern in bubble column can be divided into transient flow zone and fully developed flow zone. Local gas holdup increases with the increase of axial height in the transient flow zone, and remains constant with the change of axial height in fully developed flow zone. Radial profile of gas holdup is in parabolic shape. The probability density distribution of bubble size under high gas velocity is wider than that under low gas velocity, and become wider with the increase of axial height.