Patent US3720043A successfully refreshed from Google Patents.
US3720043A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for high efficiency filtering system
Assignee: North American Carbon Inc
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Filing: 1970-06-22
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Granted: 1973-03-13
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Expires: 1990-06-22
Abstract
Abstract A method for high efficiency filtration of both gaseous and particulate radioactive contaminants characterized by a single pass of an air stream carrying the contaminants through a single bed of granular materials and then venting the filtered stream to the surrounding environment. The granular bed is characterized by a given minimum depth of adsorbent particles of a given minimum size range which preferably is calculated on a basis dependent upon a given minimum removal efficiency of radioactive gaseous and particulate matter.
Inventors
- 👤 J Kovach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:31
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; B01D53/04; B01D53/0407; B01D53/0423; B01D46/00; B01D46/30; B01D53/0446; B01D2253/00; B01D2253/10; B01D2253/102; B01D2253/104; B01D2253/106; B01D2253/108; B01D2257/00; B01D2257/93; B01D2258/00; B01D2258/02; B01D2258/0283; B01D2259/00; B01D2259/40; B01D2259/40083; B01D2259/40084; B01D2259/40088; B01D2259/4009
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
139 words
A process for decontamination of a gaseous stream carrying radioactive contaminants comprising the steps of causing said gaseous stream to pass through a bed of adsorbent particles, the depth of said bed being at least approximately six inches or greater and the particle size range of said adsorbent particles being at least 8 X 12 mesh or greater as specified in ASTM Standard E-11, as the depth of said bed is increased above 6 inches, the particle size of the adsorbent particles comprising said bed is increased above above said 8 X 12 mesh, and wherein the pressure drop across said bed is less than one inch w.g. per inch depth of bed when based upon an entering gas stream velocity of at least approximately 70 feet per minute; and subsequently venting said filtered stream to the surrounding environment.
Claim 2
Dependent Claim
139 words
A process for decontamination of a gaseous stream carrying radioactive contaminants comprising the steps of causing said gaseous stream to pass through a bed of adsorbent particles, the depth of said bed being at least approximately six inches or greater and the particle size range of said adsorbent particles being at least 8 X 12 mesh or greater as specified in ASTM Standard E-11, as the depth of said bed is increased above 6 inches, the particle size of the adsorbent particles comprising said bed is increased above above said 8 X 12 mesh, and wherein the pressure drop across said bed is less than one inch w.g. per inch depth of bed when based upon an entering gas stream velocity of at least approximately 70 feet per minute; and subsequently venting said filtered stream to the surrounding environment.
Claim 3
Dependent Claim
41 words
The process defined in claim 1 wherein said adsorbent particles are activated carbon having a size range of at least 6 X 12 mesh as specified in ASTM Standard E-11 and the depth of said bed is at least 7 inches.
Claim 4
Dependent Claim
42 words
The process defined in claim 1 wherein the depth of said bed of adsorbent particles is at least 8 inches and the particle size of said particles is at least 4 X 6 meSh or greater as specified in ASTM Standard E-11.
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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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |