Patent US2657568A successfully refreshed from Google Patents.
Patent US4756874A successfully refreshed from Google Patents.
US4756874A
Expired / Lapsed
US
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Minimization of radioactive material deposition in water-cooled nuclear reactors
Assignee: General Electric Co
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Filing: 1986-12-22
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Granted: 1988-07-12
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Expires: 2006-12-22
Abstract
Abstract In water-cooled nuclear reactors where zinc is added to the water to remove or lessen the accumulation of radioactive cobalt, radioactivity arising from the zinc itself as a result of neutron capture is lessened or eliminated entirely by modifying the isotopic composition of the zinc prior to its injection into the system. The modification of the isotopic composition consists of lowering the proportion of 64 Zn or removing this isotope entirely.
Inventors
- 👤 Carl P. Ruiz
- 👤 David M. Blaies
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:49
CPC Classifications
G; G21; G21F; G21F9/00; G21F9/001; G21C; G21C19/00; G21C19/28; G21D; G21D1/00; G21D1/003; Y; Y02; Y02E; Y02E30/00; Y02E30/30; Y10; Y10S; Y10S376/00; Y10S376/90; Y10S376/904
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
51 words
In the method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor which comprises adding zinc ion to water entering said water-bearing vessel, the improvement in which said zinc ion contains a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 2
Dependent Claim
51 words
In the method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor which comprises adding zinc ion to water entering said water-bearing vessel, the improvement in which said zinc ion contains a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 3
Dependent Claim
23 words
A method in accordance with claim 1 in which the proportion of 64 Zn in said zinc ion is less than about 10%.
Claim 4
Dependent Claim
23 words
A method in accordance with claim 1 in which the proportion of 64 Zn in said zinc ion is less than about 1%.
Claim 5
Dependent Claim
18 words
A method in accordance with claim 1 in which said zinc ion is substantially devoid of 64 Zn.
Claim 6
Dependent Claim
21 words
A method in accordance with claim 1 in which said zinc ion is added by dissolving zinc oxide in said water.
Claim 7
Dependent Claim
33 words
A method in accordance with claim 5 in which the amount of zinc oxide dissolved is selected to achieve a concentration of about 1 to about 1,000 ppb zinc in said water-bearing vessel.
Claim 8
Dependent Claim
33 words
A method in accordance with claim 5 in which the amount of zinc oxide dissolved is selected to achieve a concentration of about 3 to about 100 ppb zinc in said water-bearing vessel.
Claim 9
Dependent Claim
33 words
A method in accordance with claim 5 in which said zinc oxide is dissolved from a member selected from the group consisting of a water-based slurry, a water-based paste and a water-based solution.
Claim 10
Independent Claim
52 words
A method for inhibiting the deposition of radioactive material in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding a water-based zinc oxide paste to water entering said water-bearing vessel, the zinc in said paste containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 11
Independent Claim
52 words
A method for inhibiting the deposition of radioactive material in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding a water-based zinc oxide paste to water entering said water-bearing vessel, the zinc in said paste containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 12
Dependent Claim
26 words
A method in accordance with claim 9 in which the amount of zinc oxide in said paste is from about 25% to about 95% by weight.
Claim 13
Dependent Claim
26 words
A method in accordance with claim 9 in which the amount of zinc oxide in said paste is from about 40% to about 80% by weight.
Claim 14
Independent Claim
54 words
A method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding an aqueous solution of zinc oxide to water entering said water-bearing vessel, the zinc in said zinc oxide containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 15
Independent Claim
54 words
A method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding an aqueous solution of zinc oxide to water entering said water-bearing vessel, the zinc in said zinc oxide containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 16
Dependent Claim
37 words
A method in accordance with claim 12 in which said aqueous solution is formed by passing a stream of water drawn from said water entering said water-bearing vessel through a receptacle containing solid zinc oxide retained therein.
Claim 17
Dependent Claim
20 words
A method in accordance with claim 13 in which said solid zinc oxide is a bed of zinc oxide particles.
Claim 18
Dependent Claim
17 words
A method in accordance with claim 14 in which said zinc oxide particles are sintered zinc oxide.
Claim 19
Independent Claim
55 words
A method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding a slurry of zinc oxide in water to water entering said water-bearing vessel, the zinc in said zinc oxide containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 20
Independent Claim
55 words
A method for inhibiting the deposition of radioactive cobalt in a water-bearing vessel of a water-cooled nuclear reactor, said method comprising: adding a slurry of zinc oxide in water to water entering said water-bearing vessel, the zinc in said zinc oxide containing a substantially lower proportion of the 64 Zn isotope than naturally occurring zinc.
Claim 21
Dependent Claim
25 words
A method in accordance with claim 16 in which the zinc oxide content of said slurry is from about 0.1% to about 20% by weight.
Claim 22
Dependent Claim
25 words
A method in accordance with claim 16 in which the zinc oxide content of said slurry is from about 1% to about 5% by weight.
Claim 23
Dependent Claim
19 words
A method in accordance with claim 16 in which said zinc oxide in said slurry is fumed zinc oxide.
Claim 24
Dependent Claim
40 words
A method in accordance with claim 16 in which the rate of addition of said slurry to said water is selected to produce a zinc content in the water of said water-bearing vessel of about 1 to about 1,000 ppb.
Claim 25
Dependent Claim
40 words
A method in accordance with claim 16 in which the rate of addition of said slurry to said water is selected to produce a zinc content in the water of said water-bearing vessel of about 3 to about 100 ppb.
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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) | 1991-07-12 | 1992-01-11 | 1992-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-12 | 1996-01-11 | 1996-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-12 | 2000-01-11 | 2000-07-12 | $7700.00 | Window Closed / Lapsed |