Nuclear reactor fuel integrity monitor

• US 9,268,034 B2
• Filed: 10/22/2014
• Issued: 02/23/2016
• Est. Priority Date: 08/31/2010
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Nishimura, Takao, Kino, Kenichiro
• Primary Examiner(s): Gaworecki, Mark R
• Assistant Examiner(s): Malkowski, Kenneth J
• Application Number:
  US14/520,887
• Publication Number:
  US 20150115157A1
• Time in Patent Office: 489 Days
• Field of Search: 250/370.02, 250/370.03
• US Class Current: 1/1
• CPC Class Codes: G01T 1/167 Measuring radioactive content of objects, e.g. contamination whole body counters G01T1/163
• CPC Class Codes: G01T 7/02 Collecting means for receiving or storing samples to be investigated and possibly directly transporting the samples to the measuring arrangement; particularly for investigating radioactive fluids sampling, preparing specimens for investigation in general G01N1/00, G01N1/02; shielded cells or rooms structurally combined with manipulatin devices G21F; measuring of chromatographically separated samples G01N30/00 - G01N30/96
• CPC Class Codes: G21C 1/022 characterised by the design or properties of the core
• CPC Class Codes: G21C 17/02 Devices or arrangements for monitoring coolant or moderator
• CPC Class Codes: G21C 17/022 for monitoring liquid coolants or moderators
• CPC Class Codes: G21C 17/06 Devices or arrangements for monitoring or testing fuel or fuel elements outside the reactor core, e.g. for burn-up, for contamination G21C17/08, G21C17/10 take precedence; detecting leaking fuel elements during reactor operation G21C17/04
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

A nuclear reactor fuel integrity monitor includes: a γ-ray detector which detects γ-ray of a specific radionuclide of a subject measurement medium of a nuclear reactor; a sample container which retains the subject measurement medium therein and surrounds the circumference of the γ-ray detector; and a measurement control device which performs a control so that a predetermined amount of the subject measurement medium is introduced into the sample container and calculates a concentration of the specific radionuclide from γ-ray data per each unit time detected by the γ-ray detector and a volume of the subject measurement medium introduced into the sample container.

Claims

1. A nuclear reactor fuel integrity monitor comprising:

a γ

-ray detector which detects γ

-ray of a specific radionuclide of a subject measurement medium of a nuclear reactor;

a sample container which retains the subject measurement medium therein and surrounds the circumference of the γ

-ray detector;

a valve that controls an amount of the subject measurement medium to allow to flow into the sample container;

a measurement control device which controls the valve so that a predetermined amount of the subject measurement medium is introduced into the sample container, and calculates a concentration of the specific radionuclide from γ

-ray data per each unit time detected by the γ

-ray detector and a volume of the subject measurement medium introduced into the sample container; and

an analysis device which detects a concentration of hydrogen or oxygen included in the subject measurement medium; and

a volume control tank which separates a nuclear reactor coolant into a liquid phase and a gas phase, wherein

the sample container is connected to the volume control tank via a gas phase sampling point and obtains the subject measurement medium from the gas phase in the volume control tank.

2. The nuclear reactor fuel integrity monitor according to claim 1, wherein

the sample container is formed in a hollow shape and is wound on the γ

-ray detector so as to surround the γ

-ray detector in a spiral shape.

3. The nuclear reactor fuel integrity monitor according to claim 2, wherein

the subject measurement medium is a gas and the specific radionuclide is radioxenon.