METHOD FOR CONCENTRATING AQUEOUS SOLUTION CONTAINING SOLUTE INTO HIGH CONCENTRATION BY HYDRAULIC-MEMBRANE PROCESS UNDER NO DIFFERENCE IN OSMOTIC PRESSURE

摘要

The present invention relates to a method for concentrating an aqueous solution at a low pressure under no difference in osmotic pressure, and more specifically, to a method for concentrating an aqueous solution containing a solute to be concentrated at a low pressure under no difference in osmotic pressure. The method for concentrating an aqueous solution at a low pressure under no difference in osmotic pressure according to the present invention comprises the steps of: (a) discharging water from an aqueous solution to the outside, containing a solute to be concentrated, in a reverse osmosis separator, and transferring the concentrated aqueous solution to a concentrator having no difference in osmotic pressure; (b) additionally concentrating the concentrated aqueous solution by using the concentrator having no difference in osmotic pressure, comprising a feed chamber and a draw chamber divided by a reverse osmosis membrane or a forward osmosis membrane; and (c) respectively recovering the solute and water from the aqueous solution, which is additionally concentrated in the concentrator having no difference in osmotic pressure. The method for concentrating an aqueous solution at a low pressure under no difference in osmotic pressure enables the low consumption of energy, allows concentrating until 100% of the maximum aqueous solution saturation of a solute or solute concentration without using an extraction solvent, and does not require an additional osmosis-inducing solution.