Proposing and thermal/economic analysis of a novel portable HDH water desalination process using Maisotsenko humidifier and thermoelectric dehumidifier

• Maisotsenko humidifier is proposed for humidification process of a HDH desalination process . • There is no wet-bulb limitation in Maisotsenko humidifier making the process more efficient. • A system is proposed, developed and tested with thermoelectric as dehumidifier. • The system condensed 29–61 g of water per hour, varying with ambient conditions. • Running cost ranged from $0.06 to $0.156 per 100 g of water at $0.20/kWh electricity. The humidification-dehumidification (HDH) water desalination process operates at atmospheric pressure, reducing system complexity and cost. In the HDH process, air is humidified using saltwater, followed by a temperature reduction that induces water condensation. Conventional humidification methods rely on direct evaporation, limiting absolute humidity to the wet-bulb temperature, whereas the Maisotsenko thermodynamic cycle (M−cycle), primarily used in air cooling, can exceed this limit, achieving high absolute humidity in its wet working channel. This study proposes and experimentally investigates the application of an M−cycle humidifier in a portable HDH desalination for the first time. A compact, lab-scale M−cycle unit made from a super-hydrophilic sheet is used for humidification, while a thermoelectric cooler (TEC) with a saltwater-cooled hot side facilitates dehumidification. Experiments are conducted under three ambient conditions: 50 °C, 10 % relative humidity, 33 °C, 45 % relative humidity, and 22 °C, 50 % relative humidity. The M−cycle humidifier increases absolute humidity beyond wet-bulb limitations, resulting in wet channel exhaust air temperatures of 37 °C, 28 °C, and 20 °C with full saturation for the three tests, respectively. This leads to higher water vapor content in the air, significantly enhancing condensation efficiency. The TEC dehumidifier cools the air by 6 °C, 4 °C, and 3 °C, leading to condensed water production of 61 g, 44 g, and 29 g per hour, respectively. The system’s total power consumption is 227 W resulting in specific energy consumption values of 3.2, 5.1, and 7.8 kWh per kg of distilled water for the three conditions. At an electricity price of $0.20/kWh, the running cost of producing 100 g of fresh water ranged from $0.06 to $0.156, depending on ambient conditions. The results demonstrate the feasibility of the proposed M−cycle and TEC hybrid system as a cost-effective, energy-efficient solution for decentralized water desalination. Future work should focus on optimizing heat transfer in the TEC dehumidifier and improving system scalability to enhance overall performance.