A greener seawater desalination method by direct-contact spray evaporation and condensation (DCSEC): Experiments

Owing to the high specific energy consumption of conventional seawater desalination methods available hitherto, there is much motivation for designing greener desalination processes. As a greener desalination process, it should consume lower top-brine temperatures for the seawater feed as well as minimum chemical use for brine treatment. In this paper, a direct-contact spray-assisted evaporation and condensation (DCSEC) is presented that addresses the above-mentioned requirements of greener desalination. We have tested both the single-stage and multi-stage configurations of DCSEC process with seawater (3.5% by weight salinity) from Red Sea. The performance of the system was investigated for a feed flow rate of 6 L/minute when the evaporator chamber temperature was varied from 38 °C to 60 °C. From the experiments, maximum distillate production of 31 L/hr m³ was recorded at 60 °C feed temperature for a single-stage configuration. To further enhance the distillate production of DCSEC, an innovative micro/nano-bubbles (M/NBs) generator device is incorporated in the feed supply system which resulted in 34% increase in potable water production at the corresponding inlet feed temperatures.