微通道内气液传质过程比表面积的测定  

Measurement of specific surface area for gas-liquid mass transfer in microchannel

作　　者：季喜燕[1] 李军湘[1] 刘丽静[1] 

机构地区：[1]内蒙古科技大学包头师范学院化学学院,内蒙古自治区包头014030

出　　处：《计算机与应用化学》2014年第2期189-192,196,共5页Computers and Applied Chemistry

基　　金：内蒙古自治区高等学校科学研究项目(NJZY13222);内蒙古自治区自然科学基金项目(2012MS0213);内蒙古包头市科学技术局资助项目(2012 S2005-5-25)

摘　　要：为了确定微通道中气液两相传质过程中流动体系的比表面积口以及液相传质系数虹，以此来确定工艺设计及操作的具体参数。本文利用高速摄像系统对微通道中二氧化碳一蒸馏水传质过程Taylor气泡的变化过程进行了测定，并利用自编图像处理软件和MATLAB软件编程计算得到了流动体系的比表面积a。结果显示，口随着气相流速的增大而增大，但随着液相流速的增加，有所减小，且较常规通道中的比表面积大l～2个数量级。利用kLa预测公式计算得到了液相传质系数KL，在微通道中的KL数值与常规管道中的数值基本一致，kL数值几乎不随着气相流速的改变而变化，在相同的气相流速下，随着液相流速的增加而有所增大。In order to determine the specific surface area a and the liquid phase mass transfer coefficient kL for gas-liquid two-phase mass transfer process in micro-channel, so as to confirm the parameters of the process design and operation, the high-speed camera system was used to measure the variation of Taylor bubbles for carbon dioxide - distilled water mass transfer process in microcharmel, and a self-designed image processing software and MATLAB programming were utilized to calculate the specific surface area of flow system. The results showed that, the value of a increases with gas flow rates increasing, but reduces with liquid flow rates, and larger than the conventional channels 1-2 orders of magnitude. The liquid phase mass transfer coefficient kL was calculated through kLa prediction formula, and the kL values in the microchannel and conventional pipeline are basically the same, the kL values almost do not change with the change of gas flow rates, while increases with the liquid flow rates.

关 键 词：微通道 气液传质 Taylor气泡 比表面积 

分 类 号：TQ021.4[化学工程]