Advancing Solar Water Desalination Using Recycled Al Waste Films and AI Optimization: An Eco-Industrial Synergy

The global shortage of potable water and the rising environmental burden from industrial waste highlight the need for sustainable and low-cost desalination technologies. This study presents an enhanced passive solar still (PSS) that integrates recycled aluminum thin films and polypropylene insulation to improve thermal performance, freshwater productivity, and overall system sustainability. Material characterization confirms that waste-derived recycled aluminum plates possess high solar absorptivity and excellent thermal conductivity, enabling rapid heat absorption and extended thermal storage. Experimental evaluation under real climatic conditions shows that the PSS achieves a 35.5% increase in daily yield compared to the conventional solar still (CSS), supported by higher basin temperatures, improved evaporation-condensation dynamics, and reduced heat losses. Thermodynamic analysis reveals significant improvements in energy efficiency, exergy efficiency, gain output ratio, and productivity ratio, whereas economic assessment indicates a reduction in cost per liter and a shortened payback period. A machine-learning framework using RNN, XGBoost, Random Forest, and RVFL models accurately predicts hourly yield, and NSGA-II optimization identifies an optimal configuration of 18 recycled aluminum plates with 2 × 5 cm spacing. Environmental metrics confirm substantial reductions in material cost, energy consumption, and CO₂ emissions. The proposed system demonstrates a practical, scalable, and circular-economy-driven approach for decentralized freshwater production.