Experimental study of hybrid solar humidification dehumidification system for extremely saline water desalination

Abstract

In order to desalinate the extremely saline water such that produced from the shale oil or non-conventional gas extraction, a hybrid solar humidification-dehumidification system was experimentally studied. The proposed system may be also used to dispose of the brine rejected from the reverse osmosis desalination plant. An efficient design of the dehumidifier was also introduced in this work. This design not only enhances the heat transfer but also achieves low pressure drop. It was found that the utilization of solar reflector with the proposed desalination system saves 16.5% of daily electrical energy consumption. It was also found that the total consumed electrical energy was reduced by 65% when the extremely saline water was used compared to brackish water. This reduction in electrical energy consumption gives more advantage to the current studied system when compared to other desalination methods. In addition, its productivity was not affected by the water salinity. It is also capable of producing 72 kg/day when saline water of temperature 85 °C was used when the system operated at the optimal conditions for only 8 hr/day.