Light water reactor uranium fuel assembly and operation method of nuclear fuel cycle

Patent metadata

Field	Value
Publication number	US-12112857-B2
Application number	US-202217587315-A
Country	US
Kind code	B2
Filing date	Jan 28, 2022
Priority date	Mar 23, 2021
Publication date	Oct 8, 2024
Grant date	Oct 8, 2024

Abstract

According to embodiments, a light water reactor uranium fuel assembly is capable of reducing heating values of both Am-241 and Cm-244, to reduce the amount of generated vitrified waste without using fast reactors. The light water reactor uranium fuel assembly is a light water reactor uranium fuel assembly to be used in a nuclear fuel cycle that extracts. An americium isotope is extracted at the time of reprocessing of spent fuel to be added to a fuel, in which a weight fraction W (unit: wt %) of americium 241 to be added to a fuel heavy metal is in ranges of
W<−0.006e 2 +0.12e−0.43 (enrichment: 5 wt % or more), W<−0.000356e+0.00357 (enrichment: 4.2 wt % or more and less than 5.0 wt %)

with respect to an average enrichment of uranium 235 e (unit: wt %) of the fuel assembly.

First claim

What is claimed is:

1. A fresh fuel assembly for a light water reactor, comprising:
a plurality of fuel rods bundled together, including uranium fuel rods and poison rods,
wherein the uranium fuel rods contain fissile uranium and americium reprocessed from spent fuel and do not contain a neutron poison, and
wherein the poison rods contain both uranium and a neutron poison;

wherein each of the uranium fuel rods contains a wt. % of americium-241 that is:
smaller than −0.006e2+0.12e−0.43 when the uranium enrichment e is 5 wt. % or more, and
smaller than −0.000356e+0.00357 when the uranium enrichment is 4.2 wt. % or more and less than 5.0 wt. %.

Assignees

• Toshiba Kk
• Toshiba Energy Systems & Solutions Corp

Inventors

• Hiraiwa Kouji
• Yoshioka Kenichi
• Kimura Rei
• Wada Satoshi
• Sugita Tsukasa

Classifications

• G21C3/326 Primary

  comprising fuel elements of different composition; comprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods · CPC title

• G21C19/48

  Non-aqueous processes · CPC title

• G21G1/02

  in nuclear reactors (by thermonuclear reactions G21B; conversion of nuclear fuel G21C) · CPC title

• G21C3/30

  Assemblies of a number of fuel elements in the form of a rigid unit · CPC title

• Y02E30/30

  Nuclear fission reactors · CPC title