JPH01153997A - Fast reactor fuel assembly - Google Patents
Fast reactor fuel assemblyInfo
- Publication number
- JPH01153997A JPH01153997A JP62313009A JP31300987A JPH01153997A JP H01153997 A JPH01153997 A JP H01153997A JP 62313009 A JP62313009 A JP 62313009A JP 31300987 A JP31300987 A JP 31300987A JP H01153997 A JPH01153997 A JP H01153997A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- fuel
- elements
- sodium
- shell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003758 nuclear fuel Substances 0.000 title description 2
- 239000000446 fuel Substances 0.000 claims abstract description 60
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims abstract description 26
- 239000011734 sodium Substances 0.000 claims abstract description 26
- 229910052708 sodium Inorganic materials 0.000 claims abstract description 26
- 239000007788 liquid Substances 0.000 claims abstract description 15
- 238000010926 purge Methods 0.000 claims abstract description 13
- 238000001816 cooling Methods 0.000 abstract description 16
- 230000004992 fission Effects 0.000 abstract description 7
- 229910052778 Plutonium Inorganic materials 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- OYEHPCDNVJXUIW-UHFFFAOYSA-N plutonium atom Chemical compound [Pu] OYEHPCDNVJXUIW-UHFFFAOYSA-N 0.000 abstract description 3
- 238000012856 packing Methods 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 45
- 239000000463 material Substances 0.000 description 5
- 238000000034 method Methods 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- ZSLUVFAKFWKJRC-IGMARMGPSA-N 232Th Chemical compound [232Th] ZSLUVFAKFWKJRC-IGMARMGPSA-N 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 229910052776 Thorium Inorganic materials 0.000 description 2
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000005253 cladding Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011261 inert gas Substances 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000007654 immersion Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
Landscapes
- Monitoring And Testing Of Nuclear Reactors (AREA)
Abstract
Description
【発明の詳細な説明】 (産業上の利用分野) 本発明は高速炉系原子炉の燃料集合体に関する。[Detailed description of the invention] (Industrial application field) The present invention relates to a fuel assembly for a fast reactor type nuclear reactor.
(従来の技術)
従来の高速系原子炉の燃料集合体は、被覆管に密封され
たビン状燃料要素を格子状に配列し、外部を流れる冷却
材によりこれを冷却する方式である。(Prior Art) A conventional fuel assembly for a fast nuclear reactor is a system in which bottle-shaped fuel elements sealed in a cladding tube are arranged in a lattice pattern and cooled by a coolant flowing outside.
(発明が解決しようとする問題点)
従来の高速系原子炉の燃料集合体は、その燃料要素上部
に核分裂生成ガス(FPガス)を貯めるための長いプレ
ナム部を有するため高さが高くなり、そのため炉心上部
構体を大型化させる欠点があった。また、FPガスを貯
えることは、燃料に伴い増大する内圧に耐えるために被
覆管を厚くせざるを得ないだけではなく、炉心部に残る
FPガスによる中性子吸収も増大することなどから核特
性を劣化させる。さらにポンプ動力も必要以上に大きく
とらざるを得ない。この開運を解決のために、多数の燃
料要素の各々に対してFPガスを抜<FPガスバージ部
を設けるようにすることは炉心構造を複雑にする。また
、ピン状燃料集合体では炉心における燃料物質の占める
割合が小さく、また、ナトリウムの占める割合が大きく
ならざるを得ないために中性子スペクトルを軟化させ、
その結果、燃料増殖性を上げたり、しきい値が高い反応
を起させることが、難しくなる。これを避けるために、
シェルを貫通する冷却管により燃料を冷却する方式(通
常チューブインシェル型燃料と呼ばれる)をとれば燃料
物質が占める割合を太きくとることができる。しかし、
シェルを密閉するとFPガスによる内圧が大きくなり強
度確保上集合体構造物の占める比率を高くせざるを得す
、炉心の性能が落ちる6
本発明は、前述した問題点を解決することを目的とする
。(Problems to be Solved by the Invention) Conventional fuel assemblies for fast nuclear reactors have a long plenum section above the fuel element for storing fission product gas (FP gas), which increases the height of the fuel assembly. This had the disadvantage of increasing the size of the core upper structure. In addition, storing FP gas not only requires thickening of the cladding to withstand the internal pressure that increases with fuel, but also increases the absorption of neutrons by the FP gas remaining in the reactor core, which impairs nuclear properties. deteriorate. Furthermore, the pump power must be larger than necessary. In order to solve this problem, providing an FP gas barge section for removing the FP gas from each of a large number of fuel elements complicates the core structure. In addition, in pin-shaped fuel assemblies, the proportion of fuel material in the core is small, and the proportion of sodium must be large, which softens the neutron spectrum.
As a result, it becomes difficult to increase the fuel propagation property or cause a reaction with a high threshold value. To avoid this,
If the fuel is cooled by a cooling pipe that penetrates the shell (usually called a tube-in-shell type fuel), the proportion occupied by the fuel material can be increased. but,
When the shell is hermetically sealed, the internal pressure due to the FP gas increases, and in order to ensure strength, the proportion of the aggregate structure must be increased, which reduces the performance of the reactor core.6 The present invention aims to solve the above-mentioned problems. do.
(問題点を解決するための手段)
この目的を達成すべく、本発明による燃料集合体におい
ては、チューブインシェル型燃料集合体のシェル内に燃
料要素及び燃料要素間を満たすべく液体ナトリウムを内
部の燃料を浸すレベル以上に充填し、その上部にFPガ
スプレナム部を設け、FPガスプレナム部からFPガス
を集合体外部に導出するFPガスパージ機楕を有する高
速系原子炉用燃料集合体とする。(Means for Solving the Problems) In order to achieve this object, in the fuel assembly according to the present invention, liquid sodium is contained inside the shell of the tube-in-shell type fuel assembly to fill between the fuel elements and between the fuel elements. This is a fuel assembly for a fast nuclear reactor, which is filled with fuel to a level higher than immersion level, has an FP gas plenum section above it, and has an FP gas purge machine ellipse for leading out FP gas from the FP gas plenum section to the outside of the assembly.
(作 用)
1) チューブインシェル型燃料集合体にFPガスパー
ジ機構を設けることによってシェルを短尺化し、且つシ
ェル内外をほぼ等圧に保つことができる。(Function) 1) By providing the FP gas purge mechanism in the tube-in-shell type fuel assembly, the shell can be shortened and the pressure inside and outside the shell can be maintained at approximately the same pressure.
2) チューブインシェル型燃料集合体のシェル内に自
由液面を持つ形で液体ナトリウムを充填することにより
、燃料から冷却体への熱伝達を向上させ、これによって
許容温度内で出力を高めることが出来る。2) Filling the shell of a tube-in-shell fuel assembly with liquid sodium with a free liquid surface improves heat transfer from the fuel to the cooling body, thereby increasing power output within permissible temperatures. I can do it.
3)シェル内に充填された液体ナトリウムは、金属燃料
のスウェリング(照射による膨張)に対応するために設
ける燃料要素間のギャップを埋めてシェル内の熱伝達を
向上させる。3) Liquid sodium filled in the shell fills gaps between fuel elements to accommodate swelling (expansion due to irradiation) of the metal fuel, improving heat transfer within the shell.
4) シェル内に充填されたナトリウムは、不活性ガス
以外の核分裂生成物の大部分をその巾に保持する°こと
ができる。 。4) The sodium filled in the shell can retain most of the fission products other than the inert gas within its width. .
(実施例) 次に、添付図面を参照しつつ本発明の詳細な説明する。(Example) Next, the present invention will be described in detail with reference to the accompanying drawings.
中心に約5鵬の円孔を有し、横断面が、対辺距離約10
A角柱(長さは任意)の金属燃料要素1を横断面が六角
形のシェル2内に多数装填して、その燃料要素1の中心
の円孔に冷却管3を通し、その内部に冷却ナトリウム4
を流して燃料要素1を冷却する。更に、シェル2内に液
体すトリウム4を燃料要素1の上端のレベル以上まで充
填して燃料要素1と冷却管3のギャップおよび燃料要素
間のギャップを満たす。ナトリウム自由液面の上部には
、FPガスプレナム部6を設ける。燃料集合体上部には
、FPガスブレナム部6のFPガスを外部に導<FPガ
スパージ部7を設ける。FPガスパージ部7は、内部の
FPガスを導管により外部のFPガス処理装置に直接導
く方式か、或いはFPガスを燃料集合体をとりまく冷却
系のナトリウムに放出する方式のいずれでもよい。後者
の方式のものには、FPガス貯留部を設け、FPガスに
シェル内外のナトリウムを分離させると共にFPガス自
身の昇圧により外部すl・リウムにFPガスを放出させ
る方式や、ガスのみを透過させる物質で封じ切る方式な
どが、考えられる。It has a circular hole of about 5 holes in the center, and the cross section has a distance of about 10 mm across the sides.
A large number of prismatic metal fuel elements 1 (of arbitrary length) are loaded into a shell 2 with a hexagonal cross section, and a cooling pipe 3 is passed through the circular hole in the center of the fuel element 1, and cooling sodium is placed inside the shell 2. 4
to cool the fuel element 1. Furthermore, the shell 2 is filled with liquid sodium 4 up to the level of the upper end of the fuel element 1 or higher to fill the gap between the fuel element 1 and the cooling pipe 3 and the gap between the fuel elements. An FP gas plenum section 6 is provided above the sodium free liquid level. An FP gas purge section 7 is provided in the upper part of the fuel assembly for guiding the FP gas in the FP gas blemish section 6 to the outside. The FP gas purge section 7 may be of a type in which the internal FP gas is directly guided to an external FP gas treatment device through a conduit, or a type in which the FP gas is discharged into the sodium of the cooling system surrounding the fuel assembly. The latter method includes a method in which an FP gas storage section is installed, the sodium inside and outside the shell is separated from the FP gas, and the FP gas is released into the external sodium/lium by increasing the pressure of the FP gas itself, and a method in which only the gas is permeated. Possible methods include sealing it off with a substance that causes
集合体内部は、中央には炉心部8、上下にはそれぞれ軸
方向ブランケット9.10が配設される。Inside the assembly, a reactor core 8 is provided in the center, and axial blankets 9 and 10 are provided at the top and bottom, respectively.
第4図に示すように、軸方向ブランケットのブランケッ
ト要素11は、発熱が低いので燃料要素3個分を合わせ
た形状とし、ブランケット物質の比率を高めると共に各
層交互に配列を変えることにより、冷却管3のブレ、た
わみも防止できる。また、必要ならば炉心部8の中央に
同様のJいブランケット層を2層設ければ炉心中央部に
おいても第5図に示すように、半径方向ブランケット要
素12は発熱が低いために、燃料要素1と同型で釣
あるが、大型とし、周辺部は六角次の一端を切り抜いた
形状としてブランゲット物質の占める割合を大きくする
。As shown in FIG. 4, the blanket element 11 of the axial blanket has a shape that combines three fuel elements because it generates low heat, and by increasing the proportion of the blanket material and alternating the arrangement of each layer, the cooling pipe It also prevents shaking and deflection in step 3. Furthermore, if necessary, two similar blanket layers can be provided in the center of the reactor core 8. As shown in FIG. It has the same shape as No. 1, but it is larger, and the peripheral part is shaped by cutting out one end of a hexagonal shape to increase the proportion of the blanket material.
(発明の効果)
以上の如く、本発明による燃料集合体においては、チュ
ーブインシェル型燃料集合体のシェル内に燃料要素及び
燃料要素間を満すべく液体すトリウムを内部の燃料を浸
すレベル以上に充填し、その上部にFPガスブレナム部
を設け、FPガスプレナム部からFPガスを集合体外部
に導出するFPガスパージ機構を有するので下記のよう
な効果がある。(Effects of the Invention) As described above, in the fuel assembly according to the present invention, liquid thorium is added to the shell of the tube-in-shell type fuel assembly to fill the fuel elements and between the fuel elements at a level higher than that of soaking the fuel inside. The FP gas plenum is filled with gas, an FP gas plenum is provided above the FP gas plenum, and an FP gas purge mechanism is provided to lead out the FP gas from the FP gas plenum to the outside of the assembly, resulting in the following effects.
1) チューブインシェル型燃料集合体であるため、燃
料の占める比率が高く且つ構造材、ナトリウムの占める
比率が低い。そのため中性子スペクトルは硬く、プルト
ニウムの生産性能が向上し、低い中性子エネルギーでは
核分裂を起こしにくい核種も核分裂を起こし易くなる。1) Since it is a tube-in-shell fuel assembly, the ratio of fuel is high and the ratio of structural material, sodium, is low. As a result, the neutron spectrum is hard, improving plutonium production performance, and nuclides that are difficult to fission at low neutron energies become more prone to fission.
2) FPガスパージ型であるためシェル内外がほぼ
同圧に近くなり、シェル管、冷却管を薄くすることが出
来るので核分裂連鎖反応上の性能が更に向上する。また
、封じ切り型燃料におけるようなFPガス蓄積による内
圧の昇圧による制約がないため、燃料度を大きくとるこ
とが出来る。2) Since it is an FP gas purge type, the pressure inside and outside the shell is almost the same, and the shell tube and cooling tube can be made thinner, which further improves the performance in nuclear fission chain reaction. Further, since there is no restriction due to an increase in internal pressure due to FP gas accumulation as in the case of a closed-off type fuel, the fuel content can be increased.
3) FPガスパージ型としたため、燃料集合体の長
さを密封型燃料の場合に比べて短かくすることが出来る
ので炉心上部構造体の小型化など炉のコンパクト化が図
れる。3) Since it is an FP gas purge type, the length of the fuel assembly can be made shorter than in the case of a sealed fuel, so the reactor can be made more compact, such as by making the core upper structure smaller.
4) チューブインシェル型燃料集合体をFPガスバー
ジ型にすることにより、ビン型燃料要素個々にFPガス
パージta棺をとりつける場合に比べて著しくその数を
減らす(約17100以上)ことが出来る。またFPガ
スパージ機構を設計するにあたり、空間的制約が大きく
緩められる。これらのことがらFPガスパージ機構の信
顆性も向上する。4) By changing the tube-in-shell type fuel assembly to an FP gas barge type, the number can be significantly reduced (approximately 17,100 or more) compared to the case where an FP gas purge tank is attached to each bottle-type fuel element. In addition, spatial constraints are greatly relaxed when designing the FP gas purge mechanism. These factors also improve the reliability of the FP gas purge mechanism.
5) シェル内にも液体ナトリウムが充填されているた
めシェル内における熱伝達は極めて良くなる。5) Since the shell is also filled with liquid sodium, heat transfer within the shell is extremely good.
6) シェル内にも液体ナトリウムが充填されているた
めFPガスを集合体をとりまく冷却すトリウムに放出す
る場合は、FPガスにより内外のナトリウムを分離し、
且つFPガス自身の昇圧によりFPガスを外部の冷却ナ
トリウムに放出する簡単な機構が考えられる。6) Since the shell is also filled with liquid sodium, when releasing FP gas into the thorium that surrounds the assembly to cool it, separate the inside and outside sodium with FP gas,
In addition, a simple mechanism can be considered in which the FP gas is released into the external cooling sodium by increasing the pressure of the FP gas itself.
7) 充填された液体ナトリウムは、不活性ガス以外の
核分裂生成物をその中に保持する役目を果たすことが期
待される。7) The filled liquid sodium is expected to serve to retain fission products other than inert gas within it.
第1図は、本発明の高速系原子炉燃料集合体の概念を示
す斜視図であり、第2図は、高速系原子炉燃料集合体の
炉心部(第1図におけるA−A断面)における横断面図
であり、第3図は、炉心部の燃料要素横断面図であり、
第4図は、高速系燃料集合体軸方向ブランケット部(第
1図におけるB−B断面)における横断面図であり、第
5図は、半径方向ブランケット集合体の横断面図である
。
1:金属燃料要素 2ニジエル管
3:冷却管 4:冷却ナトリウム4aニジ工
ル管間冷却ナトリウム
5:充填ナトリウム 6:F’Pガスプレナム部7:
FPガスバージ部 8:炉心部
9:上部軸方向ブランケット部
10:下部軸方向ブランケット
11:軸方向ブランケット要素
12:半径方向ブランケット要素
13:エントランスノズル
14:パッド部
15;冷却系ナトリウム液面
16:FPガス
17:燃料集合体単位セル境界
18:燃料要素単位セル境界
19:ブランケット集合体単位セル境界(外4名)
第1図
第2図
第3図
第4図FIG. 1 is a perspective view showing the concept of the fast reactor fuel assembly of the present invention, and FIG. FIG. 3 is a cross-sectional view of fuel elements in the reactor core;
FIG. 4 is a cross-sectional view of the axial blanket portion of the high-speed fuel assembly (BB cross section in FIG. 1), and FIG. 5 is a cross-sectional view of the radial blanket assembly. 1: Metal fuel element 2 Steel tube 3: Cooling pipe 4: Cooling sodium 4a Cooling sodium between steel tubes 5: Filling sodium 6: F'P gas plenum section 7:
FP gas barge section 8: Core section 9: Upper axial blanket section 10: Lower axial blanket 11: Axial blanket element 12: Radial blanket element 13: Entrance nozzle 14: Pad section 15; Cooling system sodium liquid level 16: FP Gas 17: Fuel assembly unit cell boundary 18: Fuel element unit cell boundary 19: Blanket assembly unit cell boundary (external 4 people) Figure 1 Figure 2 Figure 3 Figure 4
Claims (1)
素および燃料要素間を満すべく液体ナトリウムを内部の
燃料を浸すレベル以上に充填し、その上部にFPガスプ
レナム部を設け、FPガスプレナム部からFPガスを集
合体外部に導出するFPガスパージ機構を有することを
特徴とする高速系原子炉用燃料集合体。The shell of the tube-in-shell type fuel assembly is filled with liquid sodium to fill the space between the fuel elements and between the fuel elements to a level higher than that of submerging the fuel inside, and an FP gas plenum section is provided above the shell, and the FP gas is supplied from the FP gas plenum section. A fuel assembly for a fast nuclear reactor, characterized in that it has an FP gas purge mechanism that guides FP gas to the outside of the assembly.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62313009A JPH01153997A (en) | 1987-12-10 | 1987-12-10 | Fast reactor fuel assembly |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP62313009A JPH01153997A (en) | 1987-12-10 | 1987-12-10 | Fast reactor fuel assembly |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH01153997A true JPH01153997A (en) | 1989-06-16 |
Family
ID=18036131
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP62313009A Pending JPH01153997A (en) | 1987-12-10 | 1987-12-10 | Fast reactor fuel assembly |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH01153997A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2017026372A (en) * | 2015-07-17 | 2017-02-02 | 日立Geニュークリア・エナジー株式会社 | Fast reactor fuel element, fuel assembly and reactor core loading fuel assembly |
US9589681B2 (en) | 2009-10-08 | 2017-03-07 | Commissariat A L'energie Atomique Et Aux Energies Alternatives | Nuclear fuel assembly body and a nuclear fuel assembly with such a body |
-
1987
- 1987-12-10 JP JP62313009A patent/JPH01153997A/en active Pending
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9589681B2 (en) | 2009-10-08 | 2017-03-07 | Commissariat A L'energie Atomique Et Aux Energies Alternatives | Nuclear fuel assembly body and a nuclear fuel assembly with such a body |
JP2017026372A (en) * | 2015-07-17 | 2017-02-02 | 日立Geニュークリア・エナジー株式会社 | Fast reactor fuel element, fuel assembly and reactor core loading fuel assembly |
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