Influences of Interfacial Convection and Physical Properties of Desiccant Solutions on the Mass Transfer Performance of Absorption Systems

摘要

In order to investigate the mass transfer phenomenon of the absorption of water vapor in desiccant solutions, a system of absorption cell was designed. The gradient in surface tension can result from the contact process between the desiccant solution and water vapor. This induced interfacial disturbance will affect the mass transfer performance. The experimental results demonstrate that the theoretical mass transfer coefficients predicted by boundary layer theory are less than those of the experimental values. In addition, the mass transfer performance of the absorption system can be enhanced by adding ethanol to the absorbent solutions. In order to describe the level of mass transfer performance affected by the interfacial convection resulting from the addition of ethanol, the enhancement factor was defined in this study. The enhancement factor is from 1.26 to 1.56 for adding ethanol to DEG (diethylene glycol) solution, and from 1.36 to 1.61 for adding ethanol to TEG (methylene glycol) solution.