Water recovery by electrodialysis

• US 3,268,441 A
• Filed: 05/21/1963
• Issued: 08/23/1966
• Est. Priority Date: 05/21/1963
• Status: Expired due to Term

• Current Assignee: Robert W. Lindstrom
• Original Assignee: Robert W. Lindstrom
• Inventors: Lindstrom, Robert W.
• Application Number:
  US04/281,871
• Time in Patent Office: 1,190 Days
• US Class Current: 210/638
• CPC Class Codes: B01D 61/44 Ion-selective electrodialysis
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 1/283 using coal, charred products, or inorganic mixtures containing them
• CPC Class Codes: C02F 1/42 by ion-exchange ion-exchange in general B01J
• CPC Class Codes: C02F 1/44 by dialysis, osmosis or reverse osmosis general membrane separation processes B01D61/00, membrane modules B01D63/00, electrodialysis C02F1/4693, combination of membrane modules and bioreactors C02F3/1268
• CPC Class Codes: C02F 1/469 by electrochemical separation, e.g. by electro-osmosis, electrodialysis, electrophoresis
• CPC Class Codes: C02F 1/4693 electrodialysis
• CPC Class Codes: C02F 2103/005 Black water originating from toilets
• CPC Class Codes: C02F 2303/04 Disinfection
• CPC Class Codes: C02F 9/00 Multistage treatment of water, waste water or sewage

Claims

6. A PROCESS OF RECOVERING POTABLE WATER FROM RAW URINE COMPRISING THE STEPS OF:

(A) REACTING AT LEAST A PORTION OF THE DISSOLVED UREA OF SAID RAW URINE BY THE ADDITION OF OXALIC ACID TO FORM A PERCIPITATE OF UREA OXALATE, (B) FILTERING THE RESULTING MIXTURE TO REMOVE THE UREA OXALATE AND OTHER SUSPENDED MATERIAL;

(C) TREATING THE RESULTING LIQUID WITH ACTIVATED CHARCOAL TO SUBSTANTIALLY REMOVE REMAINING ORGANIC COMPONENTS THEREFROM. (D) PASSING AT LEAST A PROTION OF THE RESULTING ORGANICFREE LIQUID THROUGH THE DESALTING CHAMBERS OF AN ION-EXCHANGE ELECTRODIALYSIS UNIT TO REMOVE DISSSOLVED SALTS THEREFROM, AND (E) TREATING THE SALT WASTE STREAM FROM THE CONCENTRATING CHAMBERS OF SAID ELECTRODIALYSIS UNIT BY A MEMBRANE PERMEATION PROCESS TO OBTAIN ADDITONAL SALT-FREE WATER THEREFROM.