Parametric analysis of thermal-pulse regeneration of activated alumina in temperature swing adsorption process used for gas dehydration

In many industrial applications of temperature swing adsorption (TSA) dryers, the heat for adsorbent generation is provided by heat sources with unstable temperatures (such as waste heat and exhaust steam); thus, the adjustments of purge gas flow rates are frequently needed to compensate the varying heating temperatures. In this study, we investigated the TSA operation method for the efficient utilization of the thermal energy with varying grades. A comprehensive mathematical model to accurately simulate the TSA drying process was presented and validated using the experimental data. A parametric study was conducted on an industrial-scale TSA compressed air dryer. The effects on the purge gas requirements of heating temperatures and purge gas flow rates were analyzed under different conditions of the feed water concentration. It was found that the purge gas requirements for cooling do not substantially vary with the heating temperatures as well as the purge gas flow rates, and even among the different feed water concentrations there is a small changing attitude of the purge gas requirements for cooling. A relationship equation between the heating temperature and the purge gas flow rate is obtained, which allows one to operate the TSA dryer to adapt to the varying conditions of the cooling water temperature and heat source temperature.