US6261457B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and product for cleaning hollow fiber material and filter
Assignee: Medivators Inc
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Filing: 1999-11-12
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Granted: 2001-07-17
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Expires: 2019-11-12
Abstract
Abstract A peracetic acid disinfectant is used to clean particulate inorganic materials such as calcium and magnesium from fibers and filters. The method allows polysulfone filtens in particulate to be reused after soaking for at least about 18 hours, and most preferably at least about 24 hours, in the peracetic acid based solution. The cleaned filters have been shown to have a reuse life of in excess of 30% and up to about 60-80% of the original life of the filter. The peracetic acid solution and method may be used to clean both hollow fiber and pleated polysulfone filters.
Inventors
- 👤 Randal Marvin Wenthold
- 👤 Christopher Gary Rasset
- 👤 Scott Blair Wright
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:31
CPC Classifications
B; B01; B01D; B01D65/00; B01D65/02; B01D2321/00; B01D2321/16; B01D2321/162; B01D2321/28
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
79 words
A method of cleaning a used filter media that comprises polysulfone, comprising the steps of: soaking the used filter media in a peracetic acid solution for a period of time sufficient to clean the filter media so that the filter media can thereafter be reused for a period of at least about 30% of an original period of use of the filter media, wherein said step of soaking comprises soaking the filter media for at least about 18 hours.
Claim 2
Independent Claim
79 words
A method of cleaning a used filter media that comprises polysulfone, comprising the steps of: soaking the used filter media in a peracetic acid solution for a period of time sufficient to clean the filter media so that the filter media can thereafter be reused for a period of at least about 30% of an original period of use of the filter media, wherein said step of soaking comprises soaking the filter media for at least about 18 hours.
Claim 3
Dependent Claim
20 words
A method of cleaning a filter media as in claim 1 , wherein the filter media comprises hollow fiber membranes.
Claim 4
Dependent Claim
22 words
A method of cleaning a filter media as in claim 1 , wherein the filter media is a pleated filter membrane .
Claim 5
Dependent Claim
37 words
A method of cleaning a filter media as in claim 1 , wherein after a first cleaning for reuse the filter media has a reuse life of about 60-80% of the original life of the filter media.
Claim 6
Dependent Claim
33 words
A method of cleaning a filter media as in claim 1 , wherein said peracetic acid solution comprises a 1% diluted solution of about 20% hydrogen peroxide, about 4% peracetic acid, and water.
Claim 7
Dependent Claim
26 words
A method of cleaning a filter media as in claim 1 , wherein the filter media is disposed in a capsule to define a capsule filter.
Claim 8
Dependent Claim
98 words
A method of cleaning a filter media as in claim 6 , further comprising reprocessing the capsule filter before the step of soaking, said reprocessing comprising: flushing a dilute peracetic acid solution at least from one side surface of the filter media to another side surface thereof; drawing said dilute peracetic acid solution into a volume defined on at least one side of the filter media and allowing said dilute peracetic acid solution to dwell for a predetermined period; and flushing said one side and said other side of the filter media with water for a predetermined period.
Claim 9
Dependent Claim
24 words
A method of cleaning a filter media as in claim 7 , further comprising again reprocessing the capsule filter after the step of soaking.
Claim 10
Dependent Claim
28 words
A method of cleaning a filter media as in claim 1 , wherein said step of soaking comprises soaking the filter media for at least about 24 hours.
Claim 11
Dependent Claim
76 words
A water filtration process comprising: providing a filter media; filtering water with the filter media until a predetermined differential pressure is established across the filter media; thereafter cleaning the filter media, said cleaning step including soaking the filter media in a peracetic acid solution, whereby the filter media is cleaned for reuse; and thereafter filtering water with said cleaned filter media, wherein said cleaning step comprises soaking the filter media for at least about 18 hours.
Claim 12
Dependent Claim
76 words
A water filtration process comprising: providing a filter media; filtering water with the filter media until a predetermined differential pressure is established across the filter media; thereafter cleaning the filter media, said cleaning step including soaking the filter media in a peracetic acid solution, whereby the filter media is cleaned for reuse; and thereafter filtering water with said cleaned filter media, wherein said cleaning step comprises soaking the filter media for at least about 18 hours.
Claim 13
Dependent Claim
13 words
A process as in claim 10 , wherein the filter media comprises polysulfone.
Claim 14
Dependent Claim
21 words
A process as in claim 11 , wherein the filter media is disposed in a capsule to define a capsule filter.
Claim 15
Dependent Claim
93 words
A process as in claim 12 , further comprising reprocessing the capsule filter before the step of soaking, said reprocessing comprising: flushing a dilute peracetic acid solution at least from one side surface of the filter media to another side surface thereof; drawing said dilute peracetic acid solution into a volume defined on at least one side of the filter media and allowing said dilute peraceic acid solution to dwell for a predetermined period; and flushing said one side and said other side of the filter media with water for a predetermined period.
Claim 16
Dependent Claim
19 words
A process as in claim 13 , further comprising again reprocessing the capsule filter after the step of soaking.
Claim 17
Dependent Claim
22 words
A process as in claim 10 , wherein said cleaning step comprises soaking the filter media for at least about 24 hours.
Claim 18
Dependent Claim
13 words
A process as in claim 15 , wherein the filter media comprises polysulfone.
Claim 19
Dependent Claim
30 words
A process as in claim 11 , wherein said cleaned filter media is used to filter water substantially until said predetermined differential pressure is again established across the filter media.
Claim 20
Dependent Claim
28 words
A process as in claim 11 , wherein said cleaned filter media is used for at least about 30% of a duration of the first said filtering step.
Claim 21
Dependent Claim
15 words
A process as in claim 11 , wherein the filter media comprises hollow fiber membranes.
Claim 22
Dependent Claim
16 words
A process as in claim 11 , wherein the filter media is a pleated filter membrane.
Claim 23
Dependent Claim
34 words
A process as in claim 11 , wherein after a first cleaning for reuse said cleaned filter media is used for at least about 60-80% of a duration of the first said filtering step.
Claim 24
Dependent Claim
28 words
A process as in claim 10 , wherein said peracetic acid solution comprises a 1% diluted solution of about 20% hydrogen peroxide, about 4% peracetic acid, and water.
References Cited (Backward Citations)
US4517081A
Cited
US4721123A
Cited
US5656302A
Cited
US5112487A
Cited
US5851483A
Cited
US5344652A
Cited
US5762798A
Cited
US5400818A
Cited
US5508046A
Cited
US5279735A
Cited
US5310524A
Cited
US5605627A
Cited
US5431817A
Cited
US6110369A
Cited
US5635195A
Cited
US5840343A
Cited
US6077435A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-07-16 | 2005-01-15 | 2005-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-07-16 | 2009-01-15 | 2009-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-07-16 | 2013-01-15 | 2013-07-17 | $7700.00 | Window Closed / Lapsed |