Uranium dioxide single crystal/nano-diamond composite fuel and preparation method thereof

A technology of nano-diamond and nano-diamond powder, which is applied in the field of nuclear power, can solve the problems of low thermal conductivity and affect fuel safety, etc., and achieve the effects of improving thermal conductivity, improving safety, and improving economy and safety.

Active Publication Date: 2020-12-11
SHANGHAI INST OF APPLIED PHYSICS - CHINESE ACAD OF SCI +1
View PDF14 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a uranium dioxide single crystal / nano-diamond composite fuel and its preparation method, thereby solving the problem that uranium dioxide fuel, which is widely used in the world, affects the safety of the fuel due to its small thermal conductivity, and is in the process of resisting serious accidents. issues with significant risks

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Uranium dioxide single crystal/nano-diamond composite fuel and preparation method thereof
  • Uranium dioxide single crystal/nano-diamond composite fuel and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] 1) Using uranyl fluoride as raw material, UO with a particle size of 50-300 μm is prepared by electrolysis 2 Single crystals were distilled under reduced pressure, ultrasonically washed with deionized water, and dried naturally. At 1300°C, high-temperature annealing in Ar atmosphere, the heating and cooling rate is 20°C / min, and the temperature is kept for 2h.

[0026] 2) Take 100-300μm self-made UO in the sieve 2 Single crystal, acetylene supported by Ar in a CVD furnace at 1300 °C to obtain coated UO 2 For single crystal, the coating time is 1.2h, and the thickness of the coating layer is 20μm.

[0027] 3) The coated 6.88g UO 2 The single crystal, 0.55g of nano-diamond powder with a particle size of 40nm and 0.1%wt of acrylic wax were added into the polytetrafluoro tank, and stirred evenly for 1h.

[0028] 4) Spray boron nitride spray on the surface of the carbon felt, dry in a drying oven at 200°C for 30 minutes, place the pad on the inside and both ends of the m...

Embodiment 2

[0032] 1) Using uranyl chloride as the raw material, the method of electrolysis is used to prepare UO with a particle size of 200-800 μm 2Single crystal, washed three times with deionized water, and dried in a vacuum oven at 100°C.

[0033] 2) Ultrasonic cleaning with deionized water was used to remove impurities, drying at 100°C, high temperature annealing at 1750°C, the sintering atmosphere was Ar, the heating and cooling rate was 5°C / min, and the holding time was 8h.

[0034] 3) Sieve homemade UO with a thickness of 200-600 μm 2 Single crystal, acetylene was carried by argon in a CVD furnace, and coated at 1500°C for 0.8h to obtain coated UO 2 Single crystal, cladding layer thickness about 10μm.

[0035] 4) The coated 7.74g UO 2 The single crystal, 0.28g of nano-diamond powder with a particle size of 0.1-1 μm and 0.5%wt of acrylic wax were added into the polytetrafluoro tank, and stirred evenly for 2h. Single crystal UO 2 The particle volume content is 90%.

[0036] 5...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention provides a uranium dioxide single crystal / nano-diamond nuclear fuel pellet and a preparation method thereof. The preparation method comprises the following steps of: S1, providing a UO2single crystal; S2, carrying out heat treatment on the UO2 single crystal; S3, coating the UO2 single crystal with a coating, namely sieving the UO2 single crystal particles, selecting the UO2 singlecrystal particles with a certain particle size, and coating the surfaces of the UO2 single crystal particles with a pyrolytic carbon coatingby adopting a chemical vapor deposition method; S4, powder mixing: putting the coated UO2 single crystal particles prepared in the step S3, nano-diamond powder and a sintering agent into a mixing tank according to a certain volume ratio, and performing sealedmixing; S5, carrying out charging; and S6, densification sintering: specifically, enabling a pressed mold to be subjected to discharge plasma rapid sintering to obtain the composite fuel. According tothe method provided by the invention, the heat conductivity of the fuel pellet is obviously improved, so that the safety of the uranium dioxide fuel pellet is improved.

Description

technical field [0001] The invention belongs to the technical field of nuclear power, and aims to solve the problem of existing uranium dioxide (UO2) 2 ) The problem of low thermal conductivity of pellets, specifically relates to a uranium dioxide single crystal / nanometer diamond composite fuel and a preparation method thereof. Background technique [0002] Uranium dioxide (UO 2 ) fuel pellets have the advantages of high melting point, good high temperature stability, good chemical stability and good radiation stability, and are widely used in existing commercial reactors. However, with the operation of the reactor and the deepening of burnup, the center temperature of the fuel pellets is too high, and the thermal conductivity of uranium oxide is small, resulting in an excessive temperature gradient of the fuel, which affects the safety of the fuel. The occurrence of the Fukushima nuclear power accident in Japan in 2011 revealed the inherent safety deficiency of existing n...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G21C3/62G21C3/58G21C21/02G21C21/16
CPCG21C3/623G21C3/58G21C21/02G21C21/16Y02E30/30
Inventor 严超林俊王鹏曹长青张锋黄鹤朱智勇卢俊强朱丽兵
Owner SHANGHAI INST OF APPLIED PHYSICS - CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products