This study investigates the utilization of a sodium polyacrylate (SP) /CaCl2 composite as an adsorbent in a low-grade-heat desalination configuration designed for Saudi Arabian conditions. A dynamic system model was developed and validated for an adsorption desalination (AD) cycle integrated with a dual-ejector and a humidification–dehumidification (HDH) unit. Two operating modes were evaluated, including a production-oriented configuration that applies internal evaporator–condenser heat recovery (HR) when no cooling effect is required. Without HR, the AD–EJ–HDH system achieves 41–56 m3/ton·day SDWP and 2. 6–2. 9 GOR, with a freshwater cost of 1. 8–2. 4 /m3 under solar driving and 0. 70–0. 90 /m3 under waste heat. With HR, performance increases to SDWP 95–155 m3/ton·day and GOR 2. 9–3. 1, while costs decrease to about 1. 34 /m3 (solar) and 0. 38 /m3 (waste heat) in June. The SP/CaCl2 composite yields about 85% higher freshwater production than silica gel in the same system, highlighting the material’s potential for high-output hybrid adsorption desalination in hot-climate regions.
Mansour et al. (Tue,) studied this question.