Influence of Microwave Irradiation on Water-vapor Desorption Capacity of Zeolites

Abstract

Typical adsortive desiccant cooling process mainly consisting of a rotary dehumidifier (D-hum) and heat exchanger can be driven with low-temperature heat energylike solar energy or waste heat. However, the desorption rate decreases and the energy consumption increases in desorption process of D-hum was found. For the efficient development of D-hum, a microwave heating type D-hum was proposed. The microwaves have the characteristics energy is readily transformed into heat inside the particles by dipole rotation and ionic conduction and selectively heats water in the adsorbent. Consequently, processes based on microwave is now considered a promising rapid desorption technology compared to conventional heating. In this study, the effect of heat and microwave irradiation on adsorbed water-vapor desorption from various type zeolites was studied. Desorption performance of water from zeolites by microwave heating under the conditions of N2 gas of 30℃ with relative humidity 40%, microwave power of 800W was compared with that for hot-air heating at 40～80℃ and microwave power of 50W. The effect of microwave irradiation was approved to be better than that of hot air heating in any zeolites.