Temporary storage container for actinide element oxides
By designing a layered and compacted temporary storage container for actinide oxides, and utilizing heat sinks and low-melting-point metal thermal conductive media, the problem of heat accumulation in actinide oxides was solved, achieving safe heat management and stable temporary storage.
Patent Information
- Application Number
- CN202421849326.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-01
- Publication Date
- 2025-10-21
- Estimated Expiration
- 2034-08-01
AI Technical Summary
In the existing technology, the high thermal power density of actinide oxides leads to heat accumulation, which may cause pressure increase inside the container, or even lead to leakage of radioactive materials or self-sintering of oxides, affecting subsequent recovery and reuse.
Design a temporary storage container for actinide oxides, comprising an outer container and an inner container. The oxides are layered and compacted, with heat sinks provided in each layer. The gap between the outer container and the inner container is filled with a low-melting-point metal thermally conductive medium. The sidewalls of the outer container gradually thicken, while the sidewalls of the inner container gradually thin, forming a tight fit.
It improves the heat dissipation of oxides, avoids internal pressure increase caused by heat accumulation, prevents leakage of radioactive materials and self-sintering of oxides, and ensures safe and reliable temporary storage and retrieval.
Smart Images
Figure CN223462014U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of spent fuel post-processing, and in particular relates to a temporary storage container for actinide oxides. Background Art
[0002] Among the high-level liquid waste generated by spent fuel reprocessing, americium and curium are the most toxic minor actinides of concern. If these wastes could be converted into isotope products, used as targets for transmutation, or incorporated into the fast reactor fuel cycle, their long-term hazards could be reduced or even eliminated. Unfortunately, neither transmutation nor fast reactor fuel cycle technology is currently mature, resulting in low market demand for americium and curium isotopes and limited production technology. Therefore, it is possible to temporarily store waste or product containing americium and curium for a period of time, allowing for their reuse once the relevant technology matures.
[0003] Due to the stable chemical properties of actinide oxides, uranium products, plutonium products, neptunium products, and MOX products are often temporarily stored in the form of oxides. Therefore, it is also possible to consider preparing the waste liquid containing americium and curium into mixed oxides for temporary storage. However, the decay heat of some isotopes of americium and curium is very high and the decay rate is slow, which causes the thermal power density of the americium-curium mixed oxide product to remain at a high level for a long time. This is the biggest difference between americium-curium mixed oxide and uranium, plutonium, and neptunium products, and it is also the biggest challenge faced by the design and processing of product containers and the heat management during the product storage stage. If a plutonium product container is used, such as Figure 1 As shown, when storing mixed americium-curium oxide, because the inner and outer containers only touch at their bottoms, the thermal conductivity of the gas between the inner and outer containers is much lower than that of metal, making it impossible to effectively dissipate the decay heat in the inner container. This will inevitably lead to heat accumulation. Heat accumulation may cause the temperature in the center of the oxide product to approach or even exceed 1000°C. This will not only cause a serious increase in the internal pressure of the product container, even exceeding the pressure limit of the product container, thereby causing radioactive material leakage, but may also cause a certain degree of self-sintering of the oxide in the high-temperature area, making future retrieval and reuse difficult. Utility Model Content
[0004] In view of the defects existing in the prior art, the purpose of the present invention is to provide an actinide oxide temporary storage container to enhance the heat dissipation effect of the container.
[0005] To achieve the above objectives, the technical solution adopted by the present invention is: an actinide oxide temporary storage container includes an outer container and an inner container, the inner container is located within the outer container, and the actinide oxides are layered in the inner container along the height direction, each layer of actinide oxides is provided with a heat sink, and each layer of actinide oxides is in a compacted state.
[0006] Further, the outer container is attached to the inner container, wherein the thickness of the inner container sidewall gradually decreases from top to bottom along the height direction, and the thickness of the outer container sidewall gradually increases from top to bottom along the height direction.
[0007] Further, there is a gap between the outer container and the inner container, and the gap is filled with a heat-conducting medium.
[0008] Further, the heat-conducting medium is a low-melting-point metal.
[0009] Further, the gap between the outer container and the inner container is 2.5-3.5 mm.
[0010] Further, the inner container is also filled with an inert gas.
[0011] Further, the outer container is provided with an outer cover for closing or opening the outer container, and the inner container is provided with an inner cover for closing or opening the inner container.
[0012] Further, the bottom of the outer container is arc-shaped and concave towards the center, and the bottom of the inner container is adapted to the outer container.
[0013] Further, the number of the inner containers is multiple, and the multiple inner containers are stacked in the outer container along the height direction.
[0014] Further, the outer container and the inner container are both made of stainless steel, and the heat sink is a stainless steel heat sink.
[0015] The effect of the present application is to layer the oxide in the inner container and set a heat sink on each layer of oxide, which can enhance the heat-conducting performance, improve the heat dissipation effect of the oxide, avoid the serious pressure increase in the storage container caused by heat accumulation, and thus cause the leakage of radioactive substances or the self-sintering phenomenon of the oxide in the high-temperature area. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 is a schematic diagram of the existing plutonium product container;
[0017] Figure 2 is an exploded structural schematic diagram of the actinide oxide temporary storage container of the present application;
[0018] Figure 3 is a schematic diagram of the cooperation relationship between the inner container and the outer container;
[0019] Figure 4 is a schematic diagram of the positional relationship of the multiple inner containers in the outer container;
[0020] MARKED DESCRIPTION:
[0021] 1, outer container; 2, inner container; 3, heat sink; 11, outer cover; 21, inner cover. DETAILED DESCRIPTION
[0022] The utility model will be further described below in combination with the drawings and specific embodiments.
[0023] As Figures 2-4 shown, the utility model provides a kind of actinide oxide temporary storage container, including outer container 1 and inner container 2, and inner container 2 is located in outer container 1, and actinide oxide is layered in inner container 2 along height direction, and heat sink 3 is arranged on each layer of actinide oxide, and each layer of actinide oxide is in compacted state.
[0024] It can be understood that for the mixed oxide with low thermal conductivity, by compacting each layer of oxide, and heat sink 3 is arranged on each layer of oxide, the heat conduction performance can be enhanced, and the oxide can be better cooled.
[0025] It can be understood that the shape of heat sink 3 is adapted to inner container 2.
[0026] In the embodiment, the pressure of compacting oxide is not less than 20Mpa, and heat sink 3 is stainless steel heat sink.
[0027] In the embodiment, outer container 1 and inner container 2 are both made of stainless steel.
[0028] Further, outer container 1 and inner container 2 are attached, wherein the thickness of the side wall of inner container 2 gradually decreases from top to bottom along the height direction, and the thickness of the side wall of outer container 1 gradually increases from top to bottom along the height direction.
[0029] In the embodiment, the thickness of the side wall of inner container 2 gradually decreases from top to bottom, forming a tapered surface with "thick top and thin bottom"; and the thickness of the side wall of outer container 1 gradually increases from top to bottom, forming a tapered surface that can closely cooperate with inner container 2. After the inner container 2 is filled with americium-cerium mixed oxide, it can closely cooperate with outer container 1 by gravity, and the decay heat of the oxide can be directly conducted through the metal, thereby greatly improving the heat conduction efficiency and reducing the temperature of the central region of the oxide.
[0030] In the embodiment, outer container 1 is similar to the glass solidification product container commonly used in the reprocessing plant, and the temporary storage container can be directly placed in the vertical shaft of the temporary storage library of the glass solidification product container in the reprocessing plant for cooling.
[0031] Further, there is a gap between outer container 1 and inner container 2, and the gap is filled with a heat-conducting medium.
[0032] Further, the heat-conducting medium is a low-melting-point metal.
[0033] Further, the gap between the outer container 1 and the inner container 2 is 2.5mm-3.5mm.
[0034] In the embodiment, low-melting-point metals such as lead and tin are filled between the inner container 2 and the outer container 1, and the low-melting-point metals are used as the heat-conducting medium between the inner container 2 and the outer container 1. The low-melting-point metals can be pre-applied to the inner wall of the outer container 1, or can be wound in the form of a wire on the outer wall of the inner container 2 after the inner container 2 is filled and capped.
[0035] Further, the inner container 2 is filled with inert gas.
[0036] Further, the outer container 1 is provided with an outer cover 11 for closing or opening the outer container 1, and the inner container 2 is provided with an inner cover 21 for closing or opening the inner container 2.
[0037] In the embodiment, the inner container 2 is put into the outer container 1 and the outer cover is welded and sealed. The outer container 1 is heated to the melting point of the low-melting-point metal, and the metal such as lead or tin is melted to fill the gap between the inner container 2 and the outer container 1. The heating device is removed, and the low-melting-point metal is solidified when the temperature of the temporary storage container decreases. Since the gap between the outer wall of the inner container 2 and the inner wall of the outer container 1 is small (2.5mm-3.5mm), the amount of low-melting-point metal filled is not large. If the mixed oxide of americium and curium needs to be retrieved, the outer container 1 only needs to be heated, and the inner container 2 can be taken out after the filling metal is melted.
[0038] Further, the bottom of the outer container 1 is arc-shaped and recessed towards the center, and the bottom of the inner container 2 is adapted to the outer container 1.
[0039] It can be understood that by setting the bottom of the outer container 1 as arc-shaped and recessed towards the center, the stability of the temporary storage container can be increased when multiple temporary storage containers are stacked up and down, and the vertical stacking stability is not affected even if the temporary storage container is slightly deformed.
[0040] In the embodiment, the arc-shaped recess of the bottom of the outer container 1 can also be matched with a special grab to realize the hoisting of the temporary storage container.
[0041] Further, the number of the inner containers 2 is multiple, and the multiple inner containers 2 are stacked in the height direction in the outer container 1.
[0042] The use principle of the temporary storage container is as follows: when it is needed to seal the oxides, the oxides are first layered and compacted into the inner container 2, and the heat radiating fins 3 are arranged on each layer of the oxides, then the inner container 2 is closed by the inner cover 21, and the inner container 2 is placed into the outer container 1.
[0043] As can be seen from the above embodiment, the oxides in the inner container are layered and compacted, and the heat radiating fins are arranged on each layer of the oxides, so that the heat conduction performance is enhanced, the heat dissipation effect of the oxides is improved, the pressure increase in the placing device caused by heat accumulation is avoided, and the leakage of radioactive substances or the self-sintering phenomenon of the oxides in the high-temperature area is avoided.
[0044] The device is not limited to the embodiments described in the specific embodiments, and other embodiments can be derived by those skilled in the art according to the technical scheme of the utility model, which also belongs to the technical innovation range of the utility model.
Claims
1. An actinide oxide temporary storage container, characterized by, Comprise: An outer container and an inner container, the inner container is located in the outer container, actinide oxide is layered in the inner container along the height direction, each layer of actinide oxide is provided with a cooling fin, and each layer of actinide oxide is in a compacted state.
2. The actinide oxide temporary storage container of claim 1, wherein: The outer container and the inner container are attached, wherein the thickness of the side wall of the inner container gradually decreases from top to bottom along the height direction, and the thickness of the side wall of the outer container gradually increases from top to bottom along the height direction.
3. The actinide oxide temporary storage container of claim 1, wherein: There is a gap between the outer container and the inner container, and the gap is filled with a heat-conducting medium.
4. The actinide oxide temporary storage container of claim 3, wherein: The heat-conducting medium is a low-melting-point metal.
5. The actinide oxide temporary storage container of claim 3, wherein: The gap between the outer container and the inner container is 2.5-3.5 mm.
6. The actinide oxide temporary storage container of claim 1, wherein: The inner container is also filled with an inert gas.
7. The actinide oxide temporary storage container of claim 1, wherein: The outer container is provided with an outer cover for closing or opening the outer container, and the inner container is provided with an inner cover for closing or opening the inner container.
8. The actinide oxide temporary storage container of claim 1, wherein: The bottom of the outer container is arc-shaped and concave towards the center, and the bottom of the inner container is adapted to the outer container.
9. The actinide oxide temporary storage container of claim 1, wherein: The number of the inner containers is multiple, and multiple inner containers are stacked in the outer container along the height direction.
10. The actinide oxide temporary storage container of claim 1, wherein: The outer container and the inner container are both made of stainless steel, and the cooling fins are stainless steel cooling fins.