| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a water treatment method by which salt content can be inexpensively and easily removed from sea water or the like with small energy.SOLUTION: The water treatment method includes: a forward osmosis step in which water to be treated is brought into contact with draw solution obtained by dissolving thermosensitive substance having lower limit critical temperature in water through a semipermeable membrane, water in the water to be treated is made to move to the draw solution through the semipermeable membrane, the diluted draw solution diluted by water and membrane concentrated water are thereby obtained; a heating step in which the diluted draw solution is heated to temperature that is less than the lower limit critical temperature and allows the thermosensitive substance to be made hydrophobic; a solid liquid separation step in which the thermosensitive substance that is heated and made hydrophobic in the heating step is subjected to solid liquid separation to be thereby separated from the diluted draw solution as a thermosensitive substance concentrated liquid; and a cooling step in which the thermosensitive substance concentrated liquid that is separated in the solid liquid separation step is cooled to temperature at which the thermosensitive substance is made hydrophilic to regenerate the draw solution.</p> |
