正丁醇和表观气速对外环流反应器内气泡特征的影响

Effects of n-Butanol and Superficial Gas Velocity on Bubble Characteristics in an External-Loop Airlift Reactor

用双探针电导探头测量了外环流反应器内空气–水和空气–正丁醇水溶液体系中气含率、气泡平均(Sauter)直径、气泡上升速度、气泡尺寸分布以及气液相界面积.考察正丁醇浓度和气速对流型和气泡特征的影响规律,用流体动力学理论和聚并机理对其进行分析.得到实验条件下正丁醇水溶液浓度影响气含率的临界浓度Ccrit.

Bubble characteristics in external-loop airlift reactor were investigated using a dual-tip conductivity probe. The parameters investigated include the average gas holdup ,bubble Sauter diameter,bubble rise velocity ,bubble size distribution and interfacial area. Air was the gas phase and the liquid phase was a mixture of water and n-butanol with different concentrations. The effects of concentration of n-butanol and superficial gas velocity were studied and analyzed from hydrodynamics and bubble coalescence. It was found that there was a critical concentration of n-butanol Ccrit above which the average gas holdup remained unchanged at a specific superficial velocity.