旋转填料床内有效传质比表面积的测定与验证实验研究

Measurement and verification of gas-liquid interfacial area in rotating packed beds

气液有效传质比表面积是衡量旋转填料床内传质速率的重要参数,采用化学吸收法测定常压下旋转填料床中丝网填料的有效传质比表面积。利用氢氧化钠溶液和碳酸钠-碳酸氢钠缓冲溶液吸收CO2,通过Danckwerts模型和拟一级反应动力学原理分别计算有效传质比表面积并进行对比验证。研究结果表明,有效传质比表面积仅与转速和喷淋密度有关,为流体力学参数,且在转速为1 300 r/min,喷淋密度为542 L/(m2.h)时达到最大;在相同操作条件下,不同吸收液所测得的有效传质比表面积相同。实验结果证实,提出的拟合计算方法是可行的。

Effective gas-liquid mass transfer interfacial area is the important parameter for measuring the rate of mass transfer in rotating packed bed.A rotating packed bed is introduced as a countercurrent gas-liquid contactor under room pressure,measuring the gas-liquid interfacial area by chemical absorption method.CO2 is adsorbed in NaOH solution and carbonate buffer solution,the interfacial area is calculated by Danckwerts model and Pseudo first order reaction kinetics.It is shown that the interfacial area is the function of rotational speed and spray density.The highest gas-liquid interfacial area is obtained when the rotational speed is 1300 r/min and the spray density is 542 L/（m^2·h）.Under the same operating conditions,the gas-liquid interfacial areas are the same by two methods.