水萃取氯丙醇的传质性能

Mass transfer performance of extraction 1-chloro-2-hydroxypropane by water

为满足水萃取氯丙醇萃取塔设计开发需要,采用单液滴法测定了水萃取氯丙醇的总传质系数,结果表明:总传质系数随着比表面积、温度的升高而增大。依据双膜理论,联合滴内、外分传质系数经验式,并引入修正的参数对传质系数方程进行了回归,建立了新的传质系数模型,将该模型应用到此萃取体系中,对比滴内、外分传质系数得出:影响传质的阻力主要集中在液滴内,可以通过提高通量来强化液滴内传质。最后,将该模型的计算值与实验值进行了比较,平均相对误差为9.626%,两者基本吻合,因此,该模型可用于水萃取氯丙醇工业设备的设计与放大。

In order to provide reference data for the industrial extraction column design, single drop technique was used to determine the overall mass transfer coefficient of extracting 1-chloro-2-hydroxypropane by water. The result shows that overall mass transfer coefficient increases with rising temperature and increasing specific surface area. According to the two-film theory, the model of mass transfer coefficient was established with the modified correlation coefficient by combining the empirical correlation of sub-transfer coefficient within and outside the droplets, which reveals that the main controlling factor exists inside droplets on the basis of comparing inside sub-mass transfer coefficient with outside sub-mass transfer coefficient. The method of enhancing mass transfer was obtained by increasing flux. The calculated and experimental values of the model were compared, with average relative error of 9. 626%, which basically agrees each other. Therefore, the model can be used in the design and scale-up of 1-chloro-2-hydroxypropane extraction process by water.