Desiccant dehumidification system for low desorption temperature

Abstract

Controlling the temperature and humidity is important to achieve a comfortable space for occupants. Numerous studies have shown that the desiccant air conditioning system offered great potential to solve this problem. However, to guaranty the continuous working of the system, desiccant air conditioning is required a regeneration process which always needs a high temperature. Most literature has shown that its required desorption temperature more than 60°C. From this motivation, with the humidity control consideration, in this present work, we performed an experimental investigation on desiccant dehumidification system for low desorption temperature. The aim of this study is to evaluate the capabilities of the desiccant system as a dehumidifier particularly focus on the dehumidifying rate and relative humidity limitation. The system was developed as a solid desiccant block which made of polymer material. The ratio between the adsorption and desorption area was equal to control the constant value of the mass flow rate of 0.1 kg/s. The alternating process between the desorption and adsorption phases was controlled by switching the time for each process 60 min and 120 min, for desorption and adsorption, respectively. The desorption temperatures were varied in the value of 35°C, 45°C, and 55°C. Adsorption temperature was introduced in the value of 20°C for all experimental conditions. The results show that a low desorption temperature still had great potential as a dehumidifier system. The dehumidifying rate increased with the increase of desorption temperature. The dehumidifying rates provided 0.34 g/s, 0.84 g/s and 1.12 g/s for desorption temperatures of 35°C, 45°C, and 55°C, respectively. The ability of the desiccant to reduce the humidity also increased with the increase of desorption temperature. For the lowest desorption temperature, even though its only at 35°C, it can reduce the relative humidity up to 20%.