Performance Optimization of Single-Slope Solar Still with Metal Scrap Heat Enhancers via Taguchi Method

This study uses Taguchi analysis to assess the performance and energy efficiency of a metal scrap-incorporating single-slope solar still (SSSS). This study examines the influence of key input variables solar intensity, wind velocity and water inlet temperature on output metrics such as daily productivity, water temperature, and glass temperature. Experimental trials were conducted with varying input parameters, and the responses were analyzed to determine the optimal conditions for improving system performance.  The use of prewarmed saline water, derived from heat energy obtained from metal waste, markedly enhanced the efficiency of the solar still. The findings indicated that the primary factors significantly affecting productivity variations were solar radiation intensity, entering water temperature, and the temperatures of both glass and water. Increased solar intensities of 750 W/m² and 900 W/m², combined with moderate water inlet temperatures of 70°C, enhanced productivity, reaching a maximum of 4.71 kg/m² under optimal conditions. Wind velocity exerted a cooling influence, diminishing system efficiency at elevated speeds, whereas moderate wind levels of 3 m/s enhanced overall heat transfer. The Two-Way Normal ANOM, contour plots, and main effects plots illustrated the synergistic effects of input parameters on system performance, underscoring the significance of parameter optimization. The research shows that solar stills may be much more efficient when they use thermal energy from metal waste and when they fine-tune operational variables. In areas where freshwater is in short supply, this study suggests a way to improve solar still designs, which might help in the hunt for long-term water purification options.