Experimental analysis of humidification–dehumidification desalination in a cartridge tray tower

ABSTRACT Schematic diagram of a cartridge-type humidification–dehumidification (HDH) desalination system consisting of a vertical cylindrical tower divided into humidification and dehumidification sections. The column contains multiple sieve trays and chimney trays arranged in a removable cartridge assembly. Heated saltwater flows downward across lower trays while air flows upward through perforations, forming bubbles. The humid air rises to the upper section, where cooler freshwater flows across trays and condensation occurs. Arrows indicate air, saltwater, and freshwater circulation loops between the tower, heater, pumps, and cooling unit. The system achieves up to 15.56 L/h freshwater production with a gain output ratio (GOR) of 3.17. In this study, a new and unique structure is used for the humidification and dehumidification chamber. A tray cartridge tower consisting of four sieves and two chimney trays has been utilized. The performance of this humidification–dehumidification system has been investigated experimentally. In addition to the humidifier and dehumidifier tray tower, this device includes saltwater heating and freshwater cooling systems, along with fresh and saltwater pumps and tanks. The tray tower offers various advantages for gas and liquid two-phase contact, including reasonable pricing, simplicity, and ease of maintenance and cleaning. These trays also address the problems caused by sedimentation in packing. The tower has a diameter of 25 cm and a height of 1.5 m. The effects of air flow rate, saltwater flow rate, freshwater flow rate, saltwater temperature, and freshwater temperature on the exit temperature of the humidification tower, dehumidification, freshwater production, and gain output ratio (GOR) will be investigated. Maximum freshwater production occurs when the inlet freshwater temperature is at its minimum, while the saltwater temperature, air flow rate, and freshwater flow rate are at their highest values. With this system, freshwater production and GOR can reach up to 15.56 L/h and 3.17, respectively.