摘要
有机胺水溶液化学吸收CO2在工业上广泛应用,对其传质过程的微观机理进行研究十分必要。文中以对流扩散方程为基础,考虑了界面阻力对传质的影响,建立了带有化学反应的气液吸收过程液相侧非稳态传质模型,得到了传质系数表达式。利用激光全息干涉仪对不同液相主体流速下单乙醇胺(MEA)水溶液化学吸收CO2过程进行了实验研究,测定了传质达到稳态时的液相侧近界面浓度、浓度边界层厚度和传质系数。结果表明:随着液相主体流速的增加,近界面浓度和浓度边界层厚度减小,而传质系数增大;MEA在水溶液中的质量分数由0.1%增大到0.2%时,CO2吸收过程达到稳态时的近界面浓度、浓度边界层厚度及传质系数均增大。传质系数模型计算值与实验值吻合良好。
The study of micromechanism of mass transfer process of CO2 absorbed into amines solution is very essential due to its broad applications in the industrial processes. On the basis of the convection-diffusion equation, taking into account the influence of interfacial resistance on the mass transfer, a non-steady state mass transfer model on liquid side was established for the process of gas-liquid absorption accompanying with chemical reaction, and the prediction model of mass transfer coefficient was obtained. The chemical absorption of CO2 into monoethanolamine （MEA） aqueous solution was investigated experimentally by a holographic interferometer at different liquid velocities. The concentration near the interface, the thickness of the concentration boundary layer and the mass transfer coefficient were determined respectively after the mass transfer attained a stable state. The results show that with the increasing of liquid velocity, the concentration near the interface and the thickness of the concentration boundary layer decrease, but the mass transfer coefficient increases; when the mass fraction of MEA in aqueous solution increases from 0. 1% to 0.2%, the concentration near the interface, the thickness of the concentration boundary layer and the mass transfer coefficient in CO2 stable absorption process are all increased. The calculated values of the mass transfer coefficients are in good agreement with the experimental data.
出处
《化学工程》
CAS
CSCD
北大核心
2009年第5期1-4,共4页
Chemical Engineering(China)
基金
国家自然科学基金资助项目(20476073)
关键词
化学吸收
激光全息干涉
界面
传质模型
CO2
chemical absorption
laser holographic interferometer
interface
mass transfer model
CO2
