Energy and Buildings, Vol.92, 128-139, 2015
Salt impregnated desiccant matrices for'open' thermochemical energy storage-Hygrothermal cyclic behaviour and energetic analysis by physical experimentation
A selection of hygroscopic salts and desiccant matrices (Salt In Matrix, SIM) were chosen from the part I of this research through characterisation of their pore structure and hygrothermal functional properties as candidate materials for a novel open thermal energy storage (TES) system. The aim of the paper was to analyse the candidate materials performance under controlled, large scale experimental tests. This was achieved through hygrothermal cyclic behaviour tests and energy and exergy analysis. Zeolite provided the highest temperature lift of all candidates due to the high amount of vapour adsorption and its fast reaction kinetics however, after the initial period (1-2 h), the moisture adsorption rate and thus heat generation decrease sharply. Zeolite also showed a sharp drop in performance over the four cycles as it requires a higher regeneration temperature (>180 degrees C) than that used (100 degrees C) for this research. SIM-3a (Vermiculite-CaCl2) was found to be the most promising candidate for open TES systems due to its high heat generated and rapid mass uptake at higher relative humidity levels. (C) 2015 Elsevier B.V. All rights reserved.