Condensation Irrigation in Solar Desalination of Saline Waters and Reuse in Subsurface Irrigation

As the world's population continues to increase and fresh water decreases, the need for desalination of sea water is increasing. Therefore, the desalination process has become a new challenge as the earth's resources must find sustainable solutions through renewable energies. Condensation irrigation (CI) combines desalination and irrigation, which can produce required energy by solar power. This research was conducted for feasibility study in Research Station of Ahvaz University. The air flow was saturated by passing over the saline water surface in the solar still. Then the saturated airflow was driven into buried drainage pipes (25 m), where the humid airflow cools gradually, and the humidity condenses along the inner pipe surface. This condense water penetrates the soil via drainage pipe perforations, and irrigates the surrounding soil. During the field test, changes in the daily production of condensation water were observed due to the surrounding environment influenced on the input temperature but the average daily fresh water production was 6 L day-1. In addition, a laboratory model was built to identify the effective two entrance temperatures on the performance of condensation irrigation. The result showed that changing the flow temperature has a great impact on the performance of condensation irrigation.