A DRAW SOLUTION FOR FORWARD OSMOSIS USING SALT OF POLYETHYLENEIMINE AND USE THEREOF

摘要

The present invention provides a draw solution for forward osmosis containing the salt of polyethyleneimine with a number average molecular weight of 4,000 or smaller as a draw solute for forward osmosis. Also, the present invention provides a method for manufacturing fluid refined by the osmotic pressure of a draw solution for forward osmosis containing a draw solute for forward osmosis, the method comprising: a first step of making fluid of a fluid source permeate through a first membrane toward the draw solution for forward osmosis by osmotic pressure; and a second step of making the fluid, which has permeated through the first membrane, pass through a second membrane, which the draw solute for forward osmosis cannot permeate through. The manufacturing method uses the draw solution for forward osmosis according to the present invention. The draw solution for forward osmosis according to the present invention exhibits excellent osmotic pressure and can recover the draw solute easily thanks to the salt of polyethyleneimine, which is a polymeric salt, used as a draw solute. A water treatment apparatus and a water treatment method using the same have energy consumption reduced in separating and recovering the draw solute and exhibit an excellent water treatment effect.