Patent US4135970A successfully refreshed from Google Patents.
US4135970A
Expired / Lapsed
US
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System for detecting the failure of a nuclear fuel rod in a nuclear reactor
Assignee: Toshiba Corp
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Filing: 1977-02-28
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Granted: 1979-01-23
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Expires: 1997-02-28
Abstract
Abstract A system for detecting the failure of a nuclear fuel rod in a nuclear reactor comprises sampling a coolant in a nuclear reactor, cooling the sampled coolant to permit 135 I in the coolant to be adsorbed on an iodine adsorption device, moving 135m Xe produced by the 135 I decay into a cover gas at the upper space of a gas-liquid separator, and introducing the 135m Xe entrained cover gas into a radioactivity detector where the radioactivity of 135m Xe is counted.
Inventors
- 👤 Norimasa Mitsutsuka
- 👤 Katsumi Kubo
- 👤 Tatsuo Miyazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:31
CPC Classifications
G; G21; G21C; G21C17/00; G21C17/02; G21C17/04; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
167 words
A system for detecting a failure of a nuclear fuel rod in a nuclear reactor comprising the steps of (a) sampling a coolant in the nuclear reactor, (b) introducing the sampled coolant into a cover gas-sealed first gas-liquid separator to remove xenon already mixed in the coolant, (c) cooling the coolant and passing the cooled coolant through an iodine adsorption device where iodine in the coolant is adsorbed on the iodine adsorption device, (d) stopping the sampling of the coolant from the nuclear reactor after a predetermined amount of coolant is passed through the adsorption device, (e) heating the coolant in the first gas-liquid separator and iodine adsorption device, (f) circulating the heated coolant through the first gas-liquid device and iodine adsorption device to permit xenon produced by decay of iodine adsorbed on the iodine adsorbing device to be moved into the cover gas in the first gas-liquid separator, and (g) introducing the xenon-entrained cover gas into a radioactivity detection where the radioactivity of xenon is detected.
Claim 2
Independent Claim
167 words
A system for detecting a failure of a nuclear fuel rod in a nuclear reactor comprising the steps of (a) sampling a coolant in the nuclear reactor, (b) introducing the sampled coolant into a cover gas-sealed first gas-liquid separator to remove xenon already mixed in the coolant, (c) cooling the coolant and passing the cooled coolant through an iodine adsorption device where iodine in the coolant is adsorbed on the iodine adsorption device, (d) stopping the sampling of the coolant from the nuclear reactor after a predetermined amount of coolant is passed through the adsorption device, (e) heating the coolant in the first gas-liquid separator and iodine adsorption device, (f) circulating the heated coolant through the first gas-liquid device and iodine adsorption device to permit xenon produced by decay of iodine adsorbed on the iodine adsorbing device to be moved into the cover gas in the first gas-liquid separator, and (g) introducing the xenon-entrained cover gas into a radioactivity detection where the radioactivity of xenon is detected.
Claim 3
Dependent Claim
20 words
A system according to claim 1, in which said coolant in the step (c) is cooled to below 200° C.
Claim 4
Dependent Claim
21 words
A system according to claim 1, in which said coolant in the heating step (e) is heated to above 300° C.
Claim 5
Dependent Claim
16 words
A system according to claim 1, in which said iodine adsorption device has a mesh-like structure.
Claim 6
Dependent Claim
26 words
A system according to claim 1, in which the coolant is caused to flow through the iodine adsorption device until an adsorption saturation state is reached.
Claim 7
Dependent Claim
14 words
A system according to claim 1, in which said iodine is 135 I .
Claim 8
Dependent Claim
14 words
A system according to claim 1, in which said iodine is 133 I .
Claim 9
Dependent Claim
14 words
A system according to claim 1, in which said iodine is 131 I .
Claim 10
Dependent Claim
14 words
A system according to claim 1, in which said xenon is 135m Xe .
Claim 11
Dependent Claim
14 words
A system according to claim 1, in which said xenon is 135 Xe .
Claim 12
Dependent Claim
14 words
A system according to claim 1, in which said xenon is 133m Xe .
Claim 13
Dependent Claim
14 words
A system according to claim 1, in which said xenon is 133 Xe .
Claim 14
Dependent Claim
14 words
A system according to claim 1, in which said xenon is 131m Xe .
Claim 15
Dependent Claim
16 words
A system according to claim 1, in which said adsorption device is made of stainless steel.
Claim 16
Dependent Claim
15 words
A system according to claim 1, in which said adsorption device is made of nickel.
Claim 17
Dependent Claim
15 words
A system according to claim 1, in which said adsorption device is made of alumina.
Claim 18
Dependent Claim
63 words
A system according to claim 1, in which the sampled coolant is, before introduced into said gas-liquid separator, introduced into another cover gas-sealed gas-liquid separator to permit a gaseous fission product in the coolant to be moved into the cover gas in the separator, and the gaseous fission product-entrained cover gass is then introduced into another radioactivity detector where the radioactivity is counted.
Claim 19
Dependent Claim
35 words
A system according to claim 1, in which before the sampled coolant is introduced into said gas-liquid separator a delayed neutron emitted from a fission product in the coolant is detected as a deloyed-neutron detector.
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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) | 1982-01-22 | 1982-07-24 | 1983-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-22 | 1986-07-24 | 1987-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-22 | 1990-07-24 | 1991-01-23 | $7700.00 | Window Closed / Lapsed |