Experimental and analytical examinations of a single-glazed solar still desalination with a spray-feeding water system with an artificial neural network

Abstract

Using solar stills to desalinate salt water effectively provides clean water in remote areas at affordable prices. It is well-established that a crucial factor in enhancing the efficiency of solar desalination systems is increasing brackish water's surface evaporation rate by minimizing surface tension and boosting thermal energy. However, recent studies and proposed ideas indicate a limited and insufficient focus on this aspect. As a response, this research introduces a novel approach to raising the temperature of saline water. This is achieved through a system that involves simultaneous saline water spraying and circulation, affecting all factors and effectively reducing the surface evaporation rate. This approach impacts factors influencing surface evaporation rates and offers advantages such as low thermal inertia, reduced surface tension, and enhanced thermal energy within the desalination system. Therefore, the main goal of this study will be to improve the performance of the solar desalination system through circulating preheated salt water spray and using artificial neural networks and machine learning algorithms to obtain the function of predicting the amount of fresh water produced. The results of this study show that the evaporative heat transfer coefficient of the introduced system is significantly larger than that of the conventional solar still unit, with an average difference of about 43.98%. Also, the results of daily water output in both systems show a significant increase and superiority of 28.75% in freshwater production for the modified system. Also, the efficiency of the improved system is 65.18% higher than that of the passive solar distillation system, and the cost per liter was 0.059 ($/L/m2). The results of this study highlight the effectiveness of the saltwater spraying technique in enhancing the performance of solar desalination systems, making it a valuable prospect for future industrial applications in desalination systems and into energy systems for smart cities as a sagacious strategy towards clean and sustainable process.