Humidification and dehumidification desalination utilizing ultrasonic atomization and direct solar energy harvesting

This study investigates the use of ultrasonic atomization in the humification and dehumidification (HDH) desalination system to capture thermal energy directly from solar radiation at low energy consumption. This use of ultrasonic atomization within the HDH desalination system aims to increase evaporation rate, solar energy capturing and freshwater production yield. The desalination setup consists of solar humidifier, ultrasonic atomizer, dehumidifier, fresh water and sea water tanks, and auxiliary components. The atomized water droplets in the solar humidifier absorb directly the incident solar energy enabling direct evaporation to humidify the air-vapor mixture. The humidified mixture flows to the dehumidifier which consists of foam packing insertions in a chamber enabling counter-current flow arrangement leading to condensation. The daily freshwater production is monitored for 6 h, and the maximum production yield obtained is 5.79 l/day/m² of direct solar capturing area. The maximum GOR obtained is 0.49. The desalination system achieved a recovery ratio 68.4 %. The findings of this study suggest to use of ultrasonic atomizer in the direct solar HDH desalination systems to improve the system performance.