US3917953A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for decreasing radiation hazard in transporting radioactive material
Assignee: Atlantic Richfield Co
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Filing: 1974-04-03
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Granted: 1975-11-04
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Expires: 1994-04-03
Abstract
Abstract At the end of their useful life, fuel rods are removed from a nuclear reactor and transferred underwater into a shipping cask. The water in the pool of the nuclear reactor system (or fuels reprocessing plant) may contain troublesome amounts of radioactive isotopes, creating biological hazards for any shipping cask unless adequately cleaned after contacting pool water. Potential contamination of substantially all of the entire exterior of the shipping cask is avoided because such shipping cask is at least predominantly immersed in fresh water within a vertically shiftable container which can be, for example, shifted between the bottom and the surface of the pool. Fresh water is supplied to the interior of the shiftable container whereby substantially all of the exterior of the shipping cask is immersed in fresh water, maintained at a pressure and/or flow velocity preventing the pool water from contacting the exterior of the shipping cask.
Inventors
- 👤 Donald D Wodrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 02:24
CPC Classifications
G; G21; G21F; G21F5/00; G21F5/06; G21F5/14
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
252 words
In a method in which the loading of a nuclear material cask is modified at a submerged zone in a pool of water contaminated with radionuclide materials, the improvement which consists of: providing a submarine container having a fresh water supply line; placing the nuclear material cask in a sealed zone substantially submerged in fresh water in said container and substantially continuously supplying pressurized fresh water to provide within the protective zone between the interior sidewalls of the container and the exterior sidewalls of the cask water pressure greater than the water pressure in the pool of contaminated water, whereby any leakage between such protective zone and the pool is from the fresh water in the protective zone to the contaminated pool water; moving the combination of contaIner, water pressure supply line, and nuclear material cask between a surface station and a submerged location in said contaminated pool; transferring items to or from the nuclear material cask to modify the loading thereof while the cask is submerged while preserving the exterior sidewalls of said cask protected by fresh water; transferring the thus modified combination of container, pressurized water, and nuclear material cask from a submerged location to a surface station; removing the nuclear material cask from the container at the surface station, the exterior sidewalls of the cask having minimized deposits from the contaminated pool water because of the continuous fresh water pressure contacting all of the principal outside surfaces of the cask during its placement, transportation, and removal from said container.
Claim 2
Dependent Claim
252 words
In a method in which the loading of a nuclear material cask is modified at a submerged zone in a pool of water contaminated with radionuclide materials, the improvement which consists of: providing a submarine container having a fresh water supply line; placing the nuclear material cask in a sealed zone substantially submerged in fresh water in said container and substantially continuously supplying pressurized fresh water to provide within the protective zone between the interior sidewalls of the container and the exterior sidewalls of the cask water pressure greater than the water pressure in the pool of contaminated water, whereby any leakage between such protective zone and the pool is from the fresh water in the protective zone to the contaminated pool water; moving the combination of contaIner, water pressure supply line, and nuclear material cask between a surface station and a submerged location in said contaminated pool; transferring items to or from the nuclear material cask to modify the loading thereof while the cask is submerged while preserving the exterior sidewalls of said cask protected by fresh water; transferring the thus modified combination of container, pressurized water, and nuclear material cask from a submerged location to a surface station; removing the nuclear material cask from the container at the surface station, the exterior sidewalls of the cask having minimized deposits from the contaminated pool water because of the continuous fresh water pressure contacting all of the principal outside surfaces of the cask during its placement, transportation, and removal from said container.
Claim 3
Dependent Claim
182 words
Apparatus useful in modifying the loading of a nuclear material cask in a submerged zone in a pool of water contaminated with radionuclide materials, said apparatus including the combination of: an open topped container having a cavity adapted to receive a nuclear material cask, such nuclear material cask being adapted for transportation through populated areas, there being a peripheral zone between the outer vertical side walls of the nuclear material cask and the inner vertical side walls of the container; sealing means adapted to seal the top of the peripheral zone; flexible conduit means adapted to supply fresh water to said peripheral zone at a pressure greater than the pressure encountered at the submerged zone at which the loading is modified; and means controlling the vertical movement of the combination of the container, seal, nuclear material cask, pressurized fresh water, and flexible conduit between a surface station and a submerged zone in a pool of water contaminated with radionuclide materials, whereby any leakage is between the peripheral zone to the pool without any leakage from the contaminated pool to the peripheral zone.
Claim 4
Dependent Claim
182 words
Apparatus useful in modifying the loading of a nuclear material cask in a submerged zone in a pool of water contaminated with radionuclide materials, said apparatus including the combination of: an open topped container having a cavity adapted to receive a nuclear material cask, such nuclear material cask being adapted for transportation through populated areas, there being a peripheral zone between the outer vertical side walls of the nuclear material cask and the inner vertical side walls of the container; sealing means adapted to seal the top of the peripheral zone; flexible conduit means adapted to supply fresh water to said peripheral zone at a pressure greater than the pressure encountered at the submerged zone at which the loading is modified; and means controlling the vertical movement of the combination of the container, seal, nuclear material cask, pressurized fresh water, and flexible conduit between a surface station and a submerged zone in a pool of water contaminated with radionuclide materials, whereby any leakage is between the peripheral zone to the pool without any leakage from the contaminated pool to the peripheral zone.
Claim 5
Dependent Claim
25 words
The container as defined in claim 2 comprising flexible accordian-like means adapted to accommodate the fresh water protection of nuclear material casks of different heights.
Claim 6
Dependent Claim
33 words
The container as defined in claim 2 comprising floatation means adapted to maintain the top edge of the container above the surface of the pool when the container is filled with fresh water.
Claim 7
Dependent Claim
61 words
Apparatus as defined in claim 4 comprising a sealing lid secured to the nuclear material cask and adapted, upon the immersion of the cask in the water of the container, to provide the sealing means sealing the top of the peripheral zone and to automatically unseal such zone upon the lifting of the cask from the container at its surface station.
Claim 8
Dependent Claim
25 words
The container as defined in claim 2 comprising means directing the flow of flushing water from the peripheral zone into the pool of contaminated water.
Claim 9
Dependent Claim
20 words
The container as defined in claim 2 in which the nuclear material cask has a remotely controlled power actuated lid.
Claim 10
Dependent Claim
16 words
The cask of claim 2 in which the container has a remotely controlled power actuated lid.
Claim 11
Dependent Claim
22 words
The cask of claim 2 in which fresh water conduit means assures controlled flushing of the interior of the nuclear material cask.
References Cited (Backward Citations)
US3046403A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |