Abstract:

The mass transfer process in the reciprocating sieve plate extraction column(RPEC)was studied.Based on the single droplet mass transfer model，the scale-up model of RPEC was established with mathematical statistics.In this model，flux，tray spacing，amplitude and frequency should be kept invariable when H_OXP（apparent height of a transfer unit）was calculated.In a RPEC of diameter 100 mm，the experiment was carried out with lincomycin-n-butanol-acid water.The experiment results showed that：H_OX（true height of a transfer unit）was related to system physical properties，apparent velocity，input energy（amplitude A×frequency f），but had nothing to do with the column diameter and axial mixing.The model caculation showed that H_OX decreased with the increase of input energy but was little affected by the change in flux.H_OXD（dispersion height of a transfer unit）is a function of column diameter D，input energy，flux U_s and system physical properties.The mass transfer in RPEC could be divided into two stages.The model could describe the first stage better，in which the increase of input energy and flux intensifies the mass transfer and reduces H_OXD effectively.But it could not describe the second stage，in which the influence of axial mixing on mass transfer dominates.The scale-up model was used to design a RPEC of diameter 325 mm, and the results showed that the prediction error of this model was less than 20%.

摘要： 对往复振动筛板萃取塔（RPEC）塔内的传质过程进行了理论分析，并在此基础上，从单液滴传质模型出发，应用数学统计方法建立了RPEC放大设计模型，即进行放大设计时应遵循通量、塔板间距、振幅和频率不变的原则计算表观传质单元高度H_OXP.采用林可霉素-正丁醇-酸水物系对塔径100 mm的RPEC实验塔研究表明：真实传质单元高度H_OX与体系物性、表观速度、输入能量（振幅A×频率f）有关，而与塔径无关，且不受轴向混合的影响，模型较好地预测了H_OX随输入能量的增加而减小，而通量的变化则对其影响较小;分散传质单元高度H_OXD是塔径D、输入能量、通量U_s和体系物性的函数，实验结果表明模型较好地描述了输入能量和通量增加强化传质起主导作用，有效降低分散传质单元高度H_OXD的传质过程部分，而不能描述轴向混合起主导作用部分.应用放大设计模型对直径325 mm的RPEC放大设计结果验证模型的预测误差在20％以内.