Experimental testing of the buoyant functioning of a coil coated with SAPO34 zeolite, designed for solar DEC (Desiccant Evaporative Cooling) systems of buildings with natural ventilation

This work reports the experimental testing of a prototype of a new adsorption stage for solar DEC (Desiccant Evaporative Cooling) systems, in which airflow is activated by natural forces. The adsorption stage takes place in an air/water coil, coated with a thin layer of zeolite SAPO34 material. The thin coating configuration allowed testing of a concept of natural buoyant airflow on the coil, both during adsorption and during desorption phases. The heat released by the sorption phenomenon drives the airflow on the coil, whereas during the desorption, hot water flows through the coil and activates the convection. The tests proved the feasibility of the concept, though revealing the need to optimize the system configuration.