US4354858A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for filtering particulates
Assignee: General Electric Environmental Services Inc
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Filing: 1981-08-27
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Granted: 1982-10-19
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Expires: 2001-08-27
Abstract
Abstract Electrically charged particulates in a gas stream are filtered from the gas stream by a filter medium comprising a porous cake composed of electrically charged particulates previously drawn from the gas stream and collected on a foraminous support structure, where the apertures of the foraminous support structure are larger than the average size of the particulates to be filtered from the gas stream by more than an order of magnitude.
Inventors
- 👤 Tribhawan Kumar
- 👤 Kris E. Wolpert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:01
CPC Classifications
B; B01; B01D; B01D46/00; B03; B03C; B03C3/00; B03C3/02; B03C3/04; B03C3/14; B03C3/155; B03C3/34; B03C3/40; B03C3/45; B03C3/51; Y; Y10; Y10S; Y10S55/00; Y10S55/05
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
94 words
An improved method for filtering particulates from a stream of particulate-laden gas comprising the steps of: (a) moving the gas including the particulates to be filtered as a stream; (b) imparting electrostatic charges to the particulates in the stream; (c) positioning across the path of the stream and downstream of the location at which the electrostatic charges are imparted to the particulates therein a metallic electrically grounded foraminous collecting structure having apertures of sizes larger than the average size of particulates to be filtered from the stream by more than an order of magnitude,
Claim 2
Dependent Claim
94 words
An improved method for filtering particulates from a stream of particulate-laden gas comprising the steps of: (a) moving the gas including the particulates to be filtered as a stream; (b) imparting electrostatic charges to the particulates in the stream; (c) positioning across the path of the stream and downstream of the location at which the electrostatic charges are imparted to the particulates therein a metallic electrically grounded foraminous collecting structure having apertures of sizes larger than the average size of particulates to be filtered from the stream by more than an order of magnitude,
Claim 3
Dependent Claim
38 words
(d) directing the gas stream containing the charged particulates through said collecting structure such that the electrostatically charged particulates are quickly accumulated as a porous filter cake by said collecting structure and are filtered from the gas stream.
Claim 4
Dependent Claim
38 words
(d) directing the gas stream containing the charged particulates through said collecting structure such that the electrostatically charged particulates are quickly accumulated as a porous filter cake by said collecting structure and are filtered from the gas stream.
Claim 5
Dependent Claim
26 words
The improved method of claim 1, further comprising positioning a second foraminous collecting structure across said stream downstream of said metallic electrically grounded foraminous collecting structure.
Claim 6
Dependent Claim
40 words
The improved method of claim 1, further comprising positioning across said stream downstream of said metallic electrically grounded foraminous collecting structure a second foraminous collecting structure having apertures smaller than the apertures of said metallic electrically grounded foraminous collecting structure.
Claim 7
Dependent Claim
29 words
The improved method of claim 1, further comprising positioning across said stream downstream of said metallic electrically grounded foraminous collecting structure a second metallic electrically grounded foraminous collecting structure.
Claim 8
Dependent Claim
45 words
The improved method of claim 1, further comprising positioning across said stream downstream of said metallic electrically grounded foraminous collecting structure a second metallic foraminous collecting structure, and maintaining said second foraminous collecting structure electrically charged with the same polarity as said electrostatically charged particulates.
Claim 9
Dependent Claim
162 words
An improved method for filtering particulates from a stream of particulate-laden gas comprising the steps of: (a) moving the gas including the particulates to be filtered as a stream; (b) imparting electrostatic charges to the particulates in the stream; and (c) positioning across said stream downstream of the location at which the electrostatic charges are imparted to the particulates therein a spaced pair of filter elements including, (i) a downstream foraminous collecting structure, and (ii) a metallic electrically grounded upstream foraminous collecting structure having apertures of sizes larger than the average size of particulates to be filtered from the stream by more than an order of magnitude and larger also than the size of the apertures in said downstream foraminous collecting structure, (d) directing the gas stream containing the charged particulates through the collecting structure such that the electrostatically charged particulates are quickly accumulated as a porous filter cake by said pair of filter elements and are filtered from the gas stream.
Claim 10
Dependent Claim
162 words
An improved method for filtering particulates from a stream of particulate-laden gas comprising the steps of: (a) moving the gas including the particulates to be filtered as a stream; (b) imparting electrostatic charges to the particulates in the stream; and (c) positioning across said stream downstream of the location at which the electrostatic charges are imparted to the particulates therein a spaced pair of filter elements including, (i) a downstream foraminous collecting structure, and (ii) a metallic electrically grounded upstream foraminous collecting structure having apertures of sizes larger than the average size of particulates to be filtered from the stream by more than an order of magnitude and larger also than the size of the apertures in said downstream foraminous collecting structure, (d) directing the gas stream containing the charged particulates through the collecting structure such that the electrostatically charged particulates are quickly accumulated as a porous filter cake by said pair of filter elements and are filtered from the gas stream.
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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) | 1985-10-18 | 1986-04-19 | 1986-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-18 | 1990-04-19 | 1990-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-18 | 1994-04-19 | 1994-10-19 | $7700.00 | Window Closed / Lapsed |