US3895465A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cleaning contaminated surfaces of nuclear power plants and recovery of removed surface particles
Assignee: Siemens AG
•
Filing: 1973-12-03
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Granted: 1975-07-22
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Expires: 1993-12-03
Abstract
Abstract Radio-actively contaminated surfaces are cleaned by blasting the surface with particles of boron trioxide propellled through a jet with compressed gas. As a result of the abrading action, the boron trioxide becomes contaminated with abraded, radio-active solid particles. The abraded solid particles are separated from the boron trioxide by admixing water to dissolve the boron trioxide and then filtering the boron trioxide aqueous solution containing abraded solid particles to separate and recover the abraded solid particles in the boron trioxide solution. The boron trioxide aqueous solution may be treated to recover boron trioxide particles. The separated radio-active particles may be sent to a treating plant for concentration and recovery of radioactive values.
Inventors
- 👤 Roland Korn
- 👤 Gunter Seyd
- 👤 Uwe Paulsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:39
CPC Classifications
F; F28; F28G; F28G1/00; F28G1/12; B; B24; B24C; B24C1/00; B24C1/003; B24C11/00; G; G21; G21C; G21C19/00; G21C19/02; G21C19/20; G21C19/207; G21F; G21F9/00; G21F9/001; G21F9/005; Y; Y02; Y02E; Y02E30/00; Y02E30/30; Y02P; Y02P70/00; Y02P70/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
74 words
IN A PROCESS FOR CLEANING OF COMPONENTS OF NUCLEAR REACTOR POWER PLANTS WHICH HAVE BEEN WETTED DURING THE OPERATION WITH H2O OR D2O. PARTICULARLY FOR THE DECONTAMINATION OF RADIO-ACTIVELY CONTAMINATED REGIONS BY MECHANICALLY ABRADING THE SURFACES TO BE CLEANED DOWN TO THE PASSIVATION LAYER OF THE BASE MATERIAL BY MEANS OF BORON TRIOXIDE PARTICLES WITH THE AID OF COMPRESSED GAS, THE IMPROVEMENT WHICH COMPRISES ADMIXING WATER WITH THE ABRADED SOLID PARTICLES AND BORON TRIOXIDE
Claim 2
Dependent Claim
74 words
IN A PROCESS FOR CLEANING OF COMPONENTS OF NUCLEAR REACTOR POWER PLANTS WHICH HAVE BEEN WETTED DURING THE OPERATION WITH H2O OR D2O. PARTICULARLY FOR THE DECONTAMINATION OF RADIO-ACTIVELY CONTAMINATED REGIONS BY MECHANICALLY ABRADING THE SURFACES TO BE CLEANED DOWN TO THE PASSIVATION LAYER OF THE BASE MATERIAL BY MEANS OF BORON TRIOXIDE PARTICLES WITH THE AID OF COMPRESSED GAS, THE IMPROVEMENT WHICH COMPRISES ADMIXING WATER WITH THE ABRADED SOLID PARTICLES AND BORON TRIOXIDE
Claim 3
Dependent Claim
32 words
Process in accordance with claim 1 wherein water is admixed with a mixture of abraded solid particles and boron trioxide particles suspended in said gas during cleaning and separated from the gas.
Claim 4
Dependent Claim
42 words
Process in accordance with claim 2 wherein a portion of said gas is admixed with said water and said mixture of abraded solid particles and boron trioxide particles to agitate the mixture and facilitate solution of the boron trioxide in the water.
Claim 5
Dependent Claim
26 words
Process in accordance with claim 1 wherein water is added to the atmosphere around the area of decontamination to precipitate abraded solid particles and boron trioxide.
Claim 6
Dependent Claim
19 words
Process in accordance with claim 1 wherein water is added to flush boron trioxide particles from the decoNtamination region.
Claim 7
Dependent Claim
21 words
Process in accordance with claim 1 including treating the aqueous solution of boron trioxide to recover solid particles of boron trioxide.
Claim 8
Dependent Claim
21 words
Process in accordance with claim 1 wherein the filtering operation is selected from the group consisting of magnetic, mechanical and ion-exchanger.
References Cited (Backward Citations)
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US2653420A
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US2665118A
Cited
US3237351A
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US3299459A
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US3455062A
Cited
US3778938A
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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) | 1978-07-21 | 1979-01-20 | 1979-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-21 | 1983-01-20 | 1983-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-21 | 1987-01-20 | 1987-07-22 | $7700.00 | Window Closed / Lapsed |