Experimental study on adsorption characteristics of a water and silica-gel based thermal energy storage (TES) system

This study is focused on characterizing the adsorption process of a sorption based thermal energy storage (TES) systems. A lab scale closed loop physi-sorption based TES system was constructed and silica-gel (SiO2) is used as the adsorbent and water as the adsorbate. Experiments are conducted to investigate the impact of the temperature change of the evaporator (T-eva) and the mass variation of the water (adsorbate) in the evaporator. Through the test results, three key findings can be identified that mainly affect the adsorption performance. First, a higher evaporator temperature leads to a greater uptake amount (X) because of the larger pressure difference and vapor mass, flow rate. Second, the measured adsorption isotherm value in a real system is approximately 29.8-56.7% of the theoretical estimation (D-A isotherm). Third, the geometry of the vapor transmission system determines the ability to transport vapor to the reactor sufficiently and stably. (C) 2016 Elsevier Ltd. All rights reserved.