Enhancing freshwater production and cost-effectiveness in humidification-dehumidification (HDH) technology: Novel wheat straw packing and configuration optimization

The sustainable utilization of water resources is a critical global concern. Humidification-Dehumidification (HDH) technology has emerged as a promising solution to meet increasing freshwater demands. This study examines the performance of HDH systems by introducing wheat straw as novel packing material and evaluating its effectiveness across multiple system configurations. The research explores the influence of different humidifier arrangements, such as parallel and counterflow setups, in both open-air and closed-air cycles. Additionally, the study investigates the role of heat recovery mechanisms in enhancing system efficiency. Results indicate that a five-stage HDH unit with wheat straw packing material demonstrates high effectiveness. In the parallel flow, open-air configuration, the humidifier achieved an impressive effectiveness of 0.8564, and the outlet air humidity reached 99.9%. Moreover, the maximum Gain Output Ratio (GOR) of 1.206 was observed in the counterflow, closed-air cycle with heat recovery configuration, resulting in a productivity rate of 0.975 L/h. The cost of freshwater production was estimated to be 2.45 EGP/L (approximately 0.07 USD/L) under counterflow and closed-air cycle conditions. These findings provide valuable insights into the efficiency and economic viability of freshwater production using HDH technology, underscoring its potential as a sustainable solution to address water scarcity challenges.