US 2006/0144685 A1 · Method for concentrating solution

Abstract

An low concentration dope is fed through a nozzle into a concentrating apparatus, and flash evaporation of the low concentration dope is performed at an end of the nozzle. The low concentration dope is concentrated thereby to an concentrating dope which is contained and heated in the concentrating apparatus. Thus part of solvents of the low concentration dope and the concentrating dope is evaporated to a solvent gas. The solvent gas is cooled and condensed in a condensing section of the concentrating apparatus, and thereafter drawn through a first exit from the concentrating apparatus. The concentrating dope is concentrated to a high concentration dope, which is drawn through a second exit from the concentrating apparatus.

Claims3

Dependent claims

A concentrating tank for concentrating a polymer solution, comprising;

a tank main body for temporary containing said polymer solution which is concentrated;
a roof disposed on said tank main body, an inclined inner surface of said roof forming a condensing surface for condensing a solvent gas evaporated from said polymer solution;
at least one flash nozzle inserted into said tank main body, said flash nozzle being disposed under a solution surface of said polymer solution in said tank main body, for discharging a supplied fresh polymer solution into said polymer solution which is concentrated in said tank main body;
and
a draining pipe connected to a bottom of said tank main body for draining a concentrated polymer solution.

2 more elements

Dependencies are inferred from the claim text.

Method for concentrating solution

Life of this patent

Method for concentrating solution

Life of this patent

Abstract

Claims3