US4277266A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ultra filtration unit comprising a tubular filter element
Assignee: Wheelabrator Canada Inc
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Filing: 1980-02-27
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Granted: 1981-07-07
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Expires: 2000-02-27
Abstract
Abstract The invention relates to a tubular filter element for use in an ultra filtration plant. The element is in the form of a tube of woven fabric which is napped on its internal surface. A cellulose filter aid is deposited, on the nap and the resulting filter element has a high collection efficiency and low filter drag making it particularly suitable for use in an air recirculation plant. The air is drawn from a working area and passed through a conventional primary collection unit and then through an ultra filtration unit containing an array of the filter elements. It is then sufficiently clean to be passed back to the working area, preferably through a HEPA filter, and this results in a substantial saving in heat energy which would otherwise be wasted.
Inventors
- 👤 Gordon A. Dick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:15
CPC Classifications
B; B01; B01D; B01D46/00; B01D46/54; B01D46/546; B01D39/00; B01D39/08; B01D39/083; B01D39/14; B01D39/16; B01D39/18; B01D46/02; B01D46/24; B01D2239/00; B01D2239/04; B01D2239/0471; B01D2239/0478; B01D2239/10; B01D2273/00; B01D2273/12; B01D2273/30; Y; Y10; Y10S; Y10S55/00; Y10S55/45
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
93 words
In an ultra filtration unit comprising an inlet and an outlet for the flow of gas therethrough, a filter element comprising a tubular wall of cloth napped on its internal surface and having a layer of filter aid material deposited thereon so as to penetrate the nap, said filter element having a hollow interior in communication with said inlet and an exterior in communication with said outlet such that said gas flowing through said ultra filtration unit passes through said cloth wall and said layer of filter aid material to be filtered thereby.
Claim 2
Dependent Claim
93 words
In an ultra filtration unit comprising an inlet and an outlet for the flow of gas therethrough, a filter element comprising a tubular wall of cloth napped on its internal surface and having a layer of filter aid material deposited thereon so as to penetrate the nap, said filter element having a hollow interior in communication with said inlet and an exterior in communication with said outlet such that said gas flowing through said ultra filtration unit passes through said cloth wall and said layer of filter aid material to be filtered thereby.
Claim 3
Dependent Claim
13 words
An ultra filtration unit according to claim 1, wherein the cloth is woven.
Claim 4
Dependent Claim
14 words
An ultra filtration unit according to claim 2, wherein the cloth is heavily napped
Claim 5
Dependent Claim
15 words
An ultra filtration unit according to claim 3, wherein the filter aid material is cellulose.
Claim 6
Dependent Claim
15 words
An ultra filtration unit according to claim 2, wherein the cloth is heavily napped terylene.
Claim 7
Dependent Claim
15 words
An ultra filtration unit according to claim 5, wherein the filter aid material is cellulose.
Claim 8
Dependent Claim
22 words
An ultra filtration unit according to claim 5, wherein the filter aid material is at least 99.5% cellulose derived from wood pulp.
Claim 9
Dependent Claim
31 words
An ultra filtration unit according to claim 5, wherein the cloth has the following approximate characteristics: weight--14 oz per sq. yd. permeability 50-60 C.FM @ 1/2" w.g. weave--2×2 twill Finish--Heavy nap.
Claim 10
Dependent Claim
27 words
An ultra filtration unit according to claim 8, wherein the cloth has the following additional characteristics: wrap--spun 2 run (Wollen System) fill--spun 2 run (Wollen System) Count--38×27.
Claim 11
Dependent Claim
22 words
An ultra filtration unit according to claim 1, wherein the filter aid material is at least 99.5% cellulose derived from wood pulp.
Claim 12
Dependent Claim
65 words
An ultra filtration unit according to claim 1, wherein the filter aid material is at least 99.5% cellulose derived from wood pulp and has the following characteristics: average length (microns) 80 thickness (microns) 16 approximate screen analysis, percentage on 40 mesh 0.8-1 percentage through 100 mesh 83-90 percentage through 200 mesh 25 filter cake density (lbs/ft 3 ) 11 to 13 approximate moisture (%) 5-7.
Claim 13
Dependent Claim
15 words
An ultra filtration unit according to claim 11, wherein the cloth is heavily napped terylene.
Claim 14
Dependent Claim
31 words
An ultra filtration unit according to claim 12, wherein the cloth has the following approximate characteristics: weight--14 oz per sq. yd. permeability 50-60 C.FM @ 1/2" w.g. weave--2×2 twill finish--heavy nap.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-07-06 | 1985-01-05 | 1985-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-07-06 | 1989-01-05 | 1989-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-07-06 | 1993-01-05 | 1993-07-07 | $7700.00 | Window Closed / Lapsed |