Patent US3419949A successfully refreshed from Google Patents.
Patent US3711401A successfully refreshed from Google Patents.
US3711401A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regeneration method for dual beds of ion exchange resins
Assignee: Sybron Transition Corp
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Filing: 1971-03-08
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Granted: 1973-01-16
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Expires: 1991-03-08
Abstract
Abstract Ion exchange columns containing a layer of weak resin and a layer of strong resin are regenerated by passing partially spent regenerant through the column to regenerate the weak resin and then passing fresh regenerant through the column to regenerate the strong resin. Efficient regeneration is achieved in a downflow regeneration process and silica and calcium sulphate precipitation problems are reduced. In some cases, it is desirable to soak the strong resin in regenerant after the weak regenerant as been passed through the column in order to improve separation of the resins, shorten the total regeneration time and remove additional silica ions. The processes are preferably practiced on systems of three or more columns in which the columns are sequentially exhausted and regenerated, with at least two columns being regenerated in series.
Inventors
- 👤 R Hamilton
- 👤 A Kingsbury
- 👤 J Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:38
CPC Classifications
B; B01; B01J; B01J49/00; B01J49/05; B01J39/00; B01J39/04; B01J39/05; B01J41/00; B01J41/04; B01J41/05
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
65 words
A method according to claim 1 wherein the strongly basic resin in each column is at least partially in the silica form before regeneration, the partially spent regenerant effluent from the first column is discarded after it has been passed through the second column, and the partially spent regenerant effluent from the second column is discarded after it has been passed through the third column.
Claim 2
Dependent Claim
39 words
A method according to claim 1 wherein the lower layer of each column is contacted with regenerant after the partially spent regenerant is passed down through the column but before the fresh regenerant is passed down through the column.
Claim 3
Independent Claim
244 words
A method of regenerating an ion exchange system including at least three columns, each of said columns consisting of a layer of weakly acidic cation exchange resin above a layer of strongly acidic cation exchange resin, comprising: a. passing a quantity of partially spent regenerant substantially equal to the amount required to regenerate the layer of weakly acidic resin in a first column down through the weakly acidic resin and through a layer of strongly acidic resin in said first column, whereby the weakly acidic resin is substantially completely regenerated and the strongly acidic resin remains at least partially exhausted; and then b. passing fresh regenerant down through the first column and passing the partially spent regenerant effluent from the first column down through a second column having an upper layer of weakly acidic resin and a lower layer of strongly acidic resin, both of which are at least partially exhausted, until the lower layer of the first column and the upper layer of the second column have been substantially completely regenerated; and then c. passing fresh regenerant down through the second column and passing the partially spent regenerant effluent from the second column down through a third column having an upper layer of weakly acidic resin and a lower layer of strongly acidic resin, both of which are at least partially exhausted, until the lower layer of the second column and the upper layer of the third column have been substantially completely regenerated.
Claim 4
Dependent Claim
64 words
A method according to claim 4 wherein the weakly acidic resin in each column is at least partially in the calcium form prior to regeneration, the partially spent regenerant effluent from the first column is diluted before it is passed through the second column, and the partially spent regenerant effluent from the second column is diluted before it is passed through the third column.
Claim 5
Dependent Claim
39 words
A method according to claim 4 wherein the lower layer of each column is contacted with regenerant afTer the partially spent regenerant is passed down through the column but before the fresh regenerant is passed down through the column.
References Cited (Backward Citations)
US3505247A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |