Performance assessment of solar adsorption desalination system for sustainable cooling and freshwater maximization

Achieving sustainable cooling and freshwater requires high-performance, eco-friendly technology that produces both cooling and desalinated water. This study presents a novel utilization of promising composite adsorbent materials for a solar-powered adsorption cooling and desalination system. The proposed study utilizes silica gel-calcium chloride (SG/CaCl₂), as well as sodium polyacrylate-calcium chloride (SP/CaCl₂) and Maxsorb-calcium chloride (Max/CaCl₂) composites as potential adsorption materials. These adsorbents are employed in the adsorption cycle with and without evaporator-condenser heat recovery, in a four-bed-two-evaporator mode. The system is simulated and validated with previous experimental data. The findings indicate that the SP/CaCl₂ (with four beds and two evaporators mode) has the highest freshwater production, at 40.5 m³/ton.day, followed by Max/CaCl₂ at 38.6 m³/ton.day, and then SG/CaCl₂ at 36.4 m³/ton.day. The system also produces a cooling effect of about 773 W/kg per Max/CaCl₂, followed by SG/CaCl₂ with 728 W/kg. The study expresses the freshwater cost, indicating the potential of utilizing the proposed configuration (4-beds-two evaporators mode) using these selected adsorbent materials for producing a sustainable cooling effect and freshwater. With waste heat, the levelized freshwater cost falls as low as $0.63 m⁻³ for SP/CaCl₂ and reaches $0.82 m⁻³ for SG/CaCl_2.