US3637480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrodialysis process through supply water pretreatment on ion-exchange resins
Assignee: Individual
•
Filing: 1968-11-18
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Granted: 1972-01-25
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Expires: 1988-11-18
Abstract
Abstract A process for the desalination of salt water employing separate sodium and hydrogen form cation exchange resins to soften, to dealkalize and to partially deionize the said water prior to substantial demineralization by electrodialysis. The saltconcentrated waste stream from the electrodialysis cell may be employed to regenerate the sodium-form exchange resin that becomes exhausted during the softening step.
Inventors
- 👤 Roberto Passino
- 👤 Gianfranco Boari
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:48
CPC Classifications
B; B01; B01D; B01D65/00; B01D65/08; B01J; B01J39/00; B01J39/04; C; C02; C02F; C02F1/00; C02F1/46; C02F1/4604; C02F1/469; C02F1/4693; B01D2321/00; B01D2321/16; B01D2321/168; C02F1/42; C02F2201/00; C02F2201/46; C02F2201/461; C02F2201/46105; C02F2201/46115; Y; Y02; Y02A; Y02A20/00; Y02A20/124; Y02A20/131
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
22 words
The process of claim 1 wherein the combined water stream is degassified prior to passage of said stream into the electrodialysis cell.
Claim 2
Dependent Claim
33 words
The process of claim 1 wherein there is passed at least a portion of said salt waste stream into the exhausted sodium form cation exchanger to thereby at least partially regenerate said exchanger.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein an acid is passed into the exhausted hydrogen-form cation exchanger to thereby at least partially regenerate said exchanger.
Claim 4
Dependent Claim
12 words
The process of claim 4 wherein the acid employed is sulfuric acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |