Thermodynamic analysis and experimental study of solid/gas reactor operating in open mode

Thermochemical storage with moist air is a promising way to achieve seasonal storage of solar heat. This paper investigates the link between outlet and inlet airflow conditions in the case of hydration/dehydration of thermochemical processes operating with moist air at atmospheric pressure. A thermodynamic analysis of a solid/gas reactor operating in open mode is performed. That leads to a thermodynamic relation called charge-discharge operating line. Experimental tests have been carried out with two different reactive salts in order to prove the validity of the charge-discharge operating line. Experimental results provide a close match between the theoretical approach of the charge-discharge operating line and the measurements. Based on this relation, a reactor performance criterion, called reaction effectiveness, is defined. Both operating line and effectiveness stand as efficient design tools to predict performances of the reactor and to guide R&D choices to enhance them.