Method and apparatus for separating caustic soda and fresh water from seawater by using green energy

The present invention relates to a method and an apparatus for separating seawater into caustic soda and fresh water by using green energy, which can reduce the huge costs resulting from the fabrication of the caustic soda and the fresh water since fossil fuels and carbon dioxide emissions, which are the causes of global warming, are eliminated, with no external power supply, by self-producing the power through a generating means and separating the seawater into the caustic soda and the fresh water with the produced power. To this end, the invention comprises: a water tank which pumps a certain amount of the seawater to refine the seawater, and discharges the refined seawater; a watercourse which is connected to the one side of the water tank, and in which the seawater discharged from the water tank flows out; positive and negative electrodes which are respectively installed on both sides of the watercourse and the water tank, and electrolyze the seawater; a power supplier which is installed on the one side of the watercourse, and supplies electricity to the electrodes; a generating means which supplies self-produced power to the power supplier; and an evaporation tower through which the water that includes the caustic soda and has been electrolyzed as it had passed through the watercourse flows inward, and in which the water is simultaneously sprayed and heated so as to evaporate the moisture contained therein, thereby separating the water into the caustic soda and fresh water.