Advanced mini solar still design: Spiral heating, triangular prism condensation, and comprehensive energy-exergy analysis

Abstract

Improving solar distillation systems is crucial in addressing water scarcity by providing a sustainable solution for clean water production, while also harnessing renewable energy to reduce environmental impact and reliance on conventional power sources. In solar still systems, salt water is typically contained in a basin, where it is heated by solar energy to produce distilled water through evaporation and condensation procedure. However, traditional systems do not allow for precise control over the temperature of the saltwater. This study introduces a novel approach by integrating a spiral type solar heater for salt water heating, which elevates the saltwater temperature to higher levels. To implement the proposed set up, the integration of a spiral-type solar heater, cotton-based materials, and a perforated pipe for delivering heated saltwater should be adopted, along with intermittent water pump operation to optimize heat absorption and evaporation efficiency. This enhancement enables more efficient condensation, which is achieved using a long triangular prism condensation unit. From the obtained results, it was revealed that the proposed mini solar still system can be modified by using cotton base materials and dripping salt water from a perforated pipe can enhance the distilled water by 138.46 %. Comparing the energy efficiency results shows a significant 128.57 % efficiency improvement, highlighting the need to optimize strategies and modifications for better solar distillation performance. Comparing the optimal experiment with the reference experiment revealed a substantial 152.63 % increase in exergy efficiency.