Thermo-economic and sustainability analysis of solar-based humidification dehumidification seawater desalination system using different packing materials

The scarcity of freshwater resources is a growing challenge to sustainable development. Among the emerging solutions, humidification-dehumidification (HDH) technology has proven to be an economical and effective method for freshwater generation. In HDH systems the choice of packing materials in the humidifier significantly impacts the heat and mass transfer efficiency between air and seawater. This study explores the novelty of utilizing three distinct packing materials, namely jute fibre, coconut fibre matrix, and cellulose pad in a solar- based humidification-dehumidification desalination system. The system's performance is experimentally evaluated through thermo-economic and sustainability assessments at three airflow rates. Results show that the cellulose pad exhibits the highest specific humidity of air, resulting in the 16.8 kg/day of freshwater having 33% of overall energy efficiency at an airflow rate of 125 kg/h. This is followed by the coconut fibre matrix (15.3 kg/ day and 30.2 %, respectively), which outperforms the jute fibre (13.9 kg/day and 27.4%, respectively) due to its uniform flow distribution and larger specific surface area. The economic assessment reveals that the cellulose pad, coconut fibre matrix and jute fibre provide freshwater at a cost of 0.020, 0.022 and 0.023 $/L, respectively. The study highlights that coconut fibre, with its honeycomb-like structure, and jute fibre are cost-effective, environmentally sustainable, and locally accessible in coastal regions, making them viable alternatives for HDH systems.