Simplified analysis of heat and mass transfer model in liquid desiccant regeneration process

Abstract

Current study reveals an analytical solution of coupled heat and mass transfer processes in a packed bed liquid desiccant regenerator. This solution showed good accuracy when compared with reliable experimental data available in the literature. In order to maintain the mass transfer gradient on the interface, a high liquid desiccant flow rate is often applied in the regenerator. Hence, the solution flow rate and concentration change very little in the whole processes. The experimental results confirmed the validation of this topic. Therefore, for narrow range of operating conditions in practical regeneration process, with acceptable error we can assume that equilibrium humidity ratio is constant on the interface. The assumption of constant humidity ratio was applied in this paper for derivation of analytical solution. The effects of variables such as air and liquid desiccant flow rate, air temperature and humidity, desiccant temperature and concentration were investigated on the evaporation rate. Furthermore, a comparison is made between the present study and analytical solution given in the literature. The results showed that the present analytical solution can give better results than other analytical solutions that presented in the literature.