PURPOSE: To improve the heat transmission velocity, and to make the solute dissolved in the aqueous solution possible to be efficiently removed or concentrated, by supercooling the aqueous solution including the solute to temperatures lower than the freezing point by means of the indirect heat exchanging method, and then, by precipitating the ice depending on the method excluding above method.
CONSTITUTION: The aqueous solution to be treated is sent from the line 11 into the cooling process, in which the solution is supercooled by the indirect cooling method using the brine, etc.; and then, the solution is sent to the ice precipitation process 2 in which the supercooled state is broken by adding the seed crystal, etc., and the ice is precipitated. The concentrated mother liquor is discharged through the line 16 or is recycled, if necessary. Next, the solution is sent to the process 3 in which the ice is separated from the mother liquor, and the mother liquor sticking on the ice is washed away, by the centrifuge, etc., and thus separated mother liquor is recycled through the line 17. The ice is molten in the process 4. According to this method, the contamination of the cooling medium and the object to be cooled, like as in the conventional method (direct method), is excluded, and besides, the ice removing mechanism for the heat transmission surface is made unnecessary, and the heat transmission velocity can be improved.
TAKAHASHI SANKICHI
KOIKE SEIJI
