Patent US4231870A successfully refreshed from Google Patents.
US4231870A
Expired / Lapsed
US
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Process for regeneration of a filter medium
Assignee: Akers Mek Verksted AS
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Filing: 1979-02-16
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Granted: 1980-11-04
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Expires: 1999-02-16
Abstract
Abstract A process for regeneration of a filter medium is provided according to which the filter medium is treated with a liquid which breaks down deposited organic materials on the filter medium. The preferred liquid for regeneration of the filter medium is concentrated sulphuric acid.
Inventors
- 👤 Tron-Halvard Fladby
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:06
CPC Classifications
B; B01; B01D; B01D35/00; B01D35/12; B01D24/00; B01D24/002; B01D24/02; B01D24/10; B01D24/105; B01D24/46; B01D24/4631; B01D24/48; B01D24/4884
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
166 words
A method of cleaning and regenerating a filter which is used for filtering water but which becomes clogged with a layer of deposited microorganisms such as algae over a period of time, said method including the steps of (a) draining away the water to be filtered from both the upstream side and the downstream side of the filter, the upstream and downstream sides relating to the direction of the flow of water to be filtered therethrough, (b) directly contacting the filter with a previously formed sulfuric acid solution as the only active treatment chemical, said solution having a concentration of at least 65% sulfuric acid which is sufficient to break down and dehydrate the deposited layer, the acid solution being directed so as to first contact the upstream side of the filter, and (c) washing the filter with purified water so as to flush away the residue of the microorganisms, the washing water being directed so as to first contact the upstream side of the filter.
Claim 2
Independent Claim
166 words
A method of cleaning and regenerating a filter which is used for filtering water but which becomes clogged with a layer of deposited microorganisms such as algae over a period of time, said method including the steps of (a) draining away the water to be filtered from both the upstream side and the downstream side of the filter, the upstream and downstream sides relating to the direction of the flow of water to be filtered therethrough, (b) directly contacting the filter with a previously formed sulfuric acid solution as the only active treatment chemical, said solution having a concentration of at least 65% sulfuric acid which is sufficient to break down and dehydrate the deposited layer, the acid solution being directed so as to first contact the upstream side of the filter, and (c) washing the filter with purified water so as to flush away the residue of the microorganisms, the washing water being directed so as to first contact the upstream side of the filter.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein said filter comprises a solid element having pores therethrough.
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) | 1983-11-04 | 1984-05-05 | 1984-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-04 | 1988-05-05 | 1988-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-04 | 1992-05-05 | 1992-11-04 | $7700.00 | Window Closed / Lapsed |