Patent ID: 6017433
Filing Date: 2000-01-25
Classification: B01D,C02F,C13B,Y02A

Abstract:
A process for desalting aqueous salt solutions, said process comprising the steps of:a. providing an aqueous feed stream containing salts to be removed by a desalting process;b. providing at least one electrodeionization cell having at least a feed compartment and an adjacent concentration compartment, said feed compartment containing an ion exchange material and being isolated from the adjacent concentration compartments by an anion and a cation exchange membrane, said concentration compartment containing a turbulence promoter material;c. acidifying the feed stream to have a pH in a range of about 0-3;d. feeding the acidified feed stream of step c. to the feed compartment of the electrodeionization cell;e. supplying a liquid including water to the concentrate compartment;f. passing a DC current through the electrodeionization cell to effect a substantial desalination of the feed stream and to transport salts and acid to the concentration compartment; andg. withdrawing a less acidic desalted product and concentrate waste solutions from the feed and concentration compartments respectively of the electrodeionization cell.