Enhancing the proficiency of heat pump-driven humidification‐dehumidification desalination systems using eco-environmentally friendly organic mixtures

In the ever-evolving landscape of technology and industry, there's a growing awareness of the need for environmentally friendly solutions. This survey marks a pioneering investigation into utilizing eco-environmentally friendly organic mixtures within indirectly integrated heat pump-driven humidification-dehumidification desalination systems. Its primary objective is to determine the most effective approach for enhancing the performance of the integrated cycles: employing organic blends or implementing structural modifications. The proposed layouts for distilled water production are structured around two distinct scenarios: the first scenario involves a basic heat pump, and the second incorporates a vapor injection heat pump. To scrutinize the devised systems' performance, an exergoeconomic analysis is performed, taking into account a meticulous heat exchanger modeling approach. In addition, extensive sensitivity analysis and NSGA.II optimization are conducted based on the most efficient mixture in terms of electricity consumption at a consistent feed-water flow rate. The findings highlight a notable enhancement in the efficiency of the two developed systems when organic blends are employed instead of pure working fluids, resulting in a substantial reduction in electricity consumption. Specifically, replacing R134a with R22/R142b increased the Gain-Output-Ratio (GOR) by 42.26% for the first scenario and 29.06% for the second scenario. As a result of the cost assessment, distilled water unit costs have decreased by 12.87% and 14.32%, respectively, for the first and second scenarios. Notably, using a ternary blend slightly enhances the performance of the proposed systems compared to when a binary blend is employed. Specifically, the highest Gain-Output-Ratio (GOR) of 12.28 was achieved for the second scenario when using R142b/R22/R236fa, representing a modest 3.2% increase compared to the case where R22/R142b was utilized. Furthermore, optimizing the first and second scenarios and utilizing R22/R142 leads to an improvement of 7.31% and 12.55% in exergetic efficiency and 7.36% and 16.21% in UCDW, respectively. Ultimately, it is evident that incorporating eco-environmentally friendly organic blends in the simple heat pump, alongside their minimal ecological footprint and their role in promoting sustainability and adhering to environmental mandates, stands out as a remarkably efficient choice. In fact, the GOR of the first scenario is approximately 27.66% higher when using R142b/R22/R236fa compared to the second scenario employing a pure working fluid. Also, PP of the second scenario increases from 7.76 years to 9.66 years.