Theoretical study on salt hydrates adsorption desalination system using solar and waste energy with and without heat recovery

The environmental impact creates a need to seek eco-friendly water desalination systems to face the increased human demands and achieve sustainability. It is found that the adsorption desalination/cooling system (ADCS) is one of the advanced and promising technologies that achieve these objectives. Whereas the ADCS is based on renewable energy, environmentally friendly, and economical in terms of operation and maintenance, as well as the possibility of operating it in remote and arid areas. This work investigates the feasibility of using promising adsorbent materials in an Adsorption desalination system using waste heat and solar energy sources. Aluminum sulfate (Al₂(SO₄)₃) and copper sulfate (CuSO₄) are used as adsorbent materials to examine theoretically the performance, weather effect, and cost evaluation of the system with and without heat recovery. The model runs using MATLAB and TRNSYS data for the hot area's weather. Findings reveal that the (CuSO₄) system performs better than Al₂(SO₄)₃. When the system uses heat recovery, it operates effectively more than without heat recovery. (CuSO₄) the system produces a daily freshwater production of 8.45 m³/ton with a cooling power of 238.9 W/kg, and COP is 0.56 without heat recovery. With heat recovery applied, the daily freshwater production is increased to (24.6 m³/ton) with the cheapest production cost. In June, the freshwater production cost for (CuSO₄) system is 1 and 4.41 $/m³ for waste heat and solar energy, respectively, with heat recovery applied.