JP3756622B2

JP3756622B2 - Transport container for mixed oxide fuel body and transport / temporary storage method for the same

Info

Publication number: JP3756622B2
Application number: JP11108297A
Authority: JP
Inventors: 弘泰吉沢; 保尾沢
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1997-04-28
Filing date: 1997-04-28
Publication date: 2006-03-15
Anticipated expiration: 2017-04-28
Also published as: JPH10297678A

Description

【０００１】
【発明の属する技術分野】
本発明は、発熱性を有する混合物酸化物燃料体（ＭＯＸ燃料体）を例えば燃料処理施設から原子力発電施設等に輸送する際に使用する輸送容器、輸送方法および一時保管方法に関する。
【０００２】
【従来の技術】
プルトニウム酸化物とウラン酸化物とを混合したＭＯＸ燃料体は、ウラン酸化物からなる燃料体と異なり発熱性を有する。このような発熱性を有する燃料体の一例として使用済燃料用の輸送および貯蔵容器として、従来、例えば特開昭５７−１７９６９９号等に示された構成のもが知られている。
【０００３】
図１３は、このような従来の輸送容器の構成を例示したものである。この輸送容器１は、長尺な容器本体２と、その長手方向一端側を覆う頂部蓋３とから構成され、図示しないＭＯＸ燃料体を収納するためのバスケットを内蔵している。容器本体２の外周側には放熱用のフィン４が設けられ、底部には内部流体を排出するためのドレン孔等の既設孔５および図示しないが計測用のいくつかの既設孔が存在している。なお、同様に頂部蓋３にもいくつかの既設孔が存在している。
【０００４】
輸送時には、容器本体２の底部および頂部に着脱自在な、主に非熱伝導性部材から成る底部緩衝体６および頂部緩衝体７が設置される。また頂部蓋３等は、蓋壁から突出する配管のように強度的に弱い構造物が設置できない構成となっている。そのため、容器本体２の底部や通常輸送用の頂部蓋３は、必ずしも容器内部から外部への効果的な放熱機能を有しない。したがって、輸送時に燃料体から発生する熱は、主に熱伝導により図示しないバスケット等の内部構造物から容器本体２に伝わり、放熱フィン４により外部に放出されるが、非熱伝導性材料からなる底部緩衝体６および頂部緩衝体７の存在、ならびに前述した強度上の観点から、通常の輸送用頂部蓋３や容器本体２の底部からは放熱がされにくい。
【０００５】
ＭＯＸ新燃料体の輸送においては、使用済み燃料体の輸送の場合と異なり、振動に対する様々な対策が必要となる。例えばＭＯＸ燃料体を図示しない保護容器に入れ、この保護容器をさらにバスケットに収納した状態で輸送容器１に入れて輸送するが、この際、ＭＯＸ燃料体は保護容器に、また保護容器はバスケットにそれぞれしっかりと締め付けて拘束する必要がある。そのうえ、ＭＯＸ燃料体と他の金属との直接接触を避けたいとの要望もある。このような理由により、ＭＯＸ燃料体の輸送においては、ゴム材、樹脂材、あるいは締め付け装置等の摺動部の金属部材等、高温中で十分長時間すなわち半永久的には使用できない各種材料を輸送容器内部で使用せざるを得ないという事情がある。従ってこれらの部材については、使用期間中に定期的に点検し必要に応じて交換しなければならない。
【０００６】
ところで、ＭＯＸ燃料体の輸送工程を想定したとき、ＭＯＸ燃料体は単に移送出発地と目的地との間の移送期間のみ、輸送容器内に収納されているのではないことが、容易に推定できる。例えば、ＭＯＸ燃料体を輸送容器に装荷してから移送開始までの待機期間、あるいは、目的地に着いてからＭＯＸ燃料体を取り出すまでの待機期間等、ＭＯＸ燃料体を輸送容器に収納した状態でのいわゆる一時保管の期間が必ず生じることになる。一時保管期間はそれぞれの輸送条件により異なるであろうが、場合によっては、移送期間と同等かそれ以上になることも考えられる。移送期間に対して一時保管期間が長引けば、それだけ前述の部材の高温劣化が進行し寿命を縮めることになる。
【０００７】
従来の燃料輸送容器並びに、燃料輸送及び一時保管法においては、以上説明した一時保管時の内部部材の劣化まで考慮して対策を施した例は見あたらない。
【０００８】
【発明が解決しようとする課題】
ＭＯＸ燃料体の輸送においては、高温中で十分長時間すなわち半永久的には使用できない各種材料を、輸送容器内部で使用せざるを得ないという事情がある。したがって、一時保管の期間が長引き高温状態の期間が長引けば、それだけこれらの部材の高温劣化を招き、寿命を縮めることになる。
【０００９】
本発明は、上記事情に着目してなされたものであり、その目的とするところは、一時保管時の輸送容器内部の温度を低下させることにより、前記部材の一時保管時の高温劣化を防ぎ、これら部材の保守、点検、交換の間隔を拡大でき、全体輸送コストの低下を図ることができる混合酸化物燃料体の輸送容器および輸送・一時保管方法を提供することにある。
【００１０】
【課題を解決するための手段】
上記目的を達成するために、請求項１の発明では混合酸化物燃料体を収納する長尺な容器本体と、前記混合酸化物燃料体の頂部側が配置される前記容器本体の長手方向一端側を輸送時に覆う輸送用頂部蓋とを有し、前記混合酸化物燃料体の輸送ならびに一時保管に供する輸送容器において、前記輸送用頂部蓋のほかに、一時保管用予備蓋として冷却機能付きの蓋を兼備したことを特徴とする混合酸化物燃料体の輸送容器を提供する。
【００１１】
請求項２の発明では請求項１記載の混合酸化物燃料体の輸送容器において、一時保管用予備蓋は、容器本体の内部ガスを外方に取り出すための取り出し孔と、この取り出し孔から取り出した前記内部ガスを冷却する冷却機構と、冷却された前記内部ガスを再び前記容器本体内に取り入れるための取り入れ孔とを有し、これにより前記容器本体の内部ガスを強制的に外部の前記冷却機構に循環させて冷却することを可能とした混合酸化物燃料体の輸送容器を提供する。
【００１２】
請求項３の発明では請求項１記載の混合酸化物燃料体の輸送容器において、一時保管用予備蓋は、容器本体の内部ガスから熱を直接奪って外部へ放出する機能を有し、前記容器本体の内部ガスを外部に循環することなく冷却することを可能とした混合酸化物燃料体の輸送容器を提供する。
【００１３】
請求項４の発明では請求項１記載の混合酸化物燃料体の輸送容器において、一時保管用予備蓋は、容器本体の内部側に向く内向きフィンを有するとともに、前記容器本体の外部側に向く外向きフィンを有する混合酸化物燃料体の輸送容器を提供する。
【００１４】
請求項５の発明では請求項１記載の混合酸化物燃料体の輸送容器において、一時保管用予備蓋は、容器本体の内部側および外部側に突出した多数のヒートパイプを有する混合酸化物燃料体の輸送容器を提供する。
【００１５】
請求項６の発明では混合酸化物燃料体を輸送容器に装荷する装荷工程と、前記輸送容器を移送する移送工程と、移送前後あるいは移送途中に前記燃料体を前記輸送容器内に収納したまま待機させる一時保管工程とから成る混合酸化物燃料体の輸送・一時保管方法において、前記装荷工程では、輸送用頂部蓋のほかに冷却機能付きの一時保管用予備蓋を兼備した前記輸送容器に前記燃料体を装荷し、前記移送工程では、前記輸送容器の頂部蓋として本来の輸送用頂部蓋を使用し、前記一時保管工程では、本来の輸送用頂部蓋を冷却機能付き一時保管用予備蓋に換え、この一時保管用予備蓋で輸送容器の内部ガスを冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００１６】
請求項７の発明では請求項６記載の混合酸化物燃料体の輸送・一時保管方法において、一時保管工程では、輸送用頂部蓋を請求項２記載の一時保管用予備蓋に取り替え、輸送容器の内部ガスを強制的に外部の冷却機構に循環させて冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００１７】
請求項８の発明では請求項６記載の混合酸化物燃料体の輸送・一時保管方法において、一時保管工程では、輸送用頂部蓋を請求項３記載の一時保管用予備蓋に取り替え、輸送容器の内部ガスを輸送容器外部に取り出すことなく冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００１８】
請求項９の発明では請求項６記載の混合酸化物燃料体の輸送・一時保管方法において、一時保管工程では、輸送用頂部蓋を請求項４記載の一時保管用予備蓋に取り替え、輸送容器の内部ガスを輸送容器外部に取り出すことなく冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００１９】
請求項１０の発明では請求項６記載の混合酸化物燃料体の輸送・一時保管方法において、一時保管工程では、輸送用頂部蓋を請求項５記載の一時保管用予備蓋に取り替え、輸送容器の内部ガスを輸送容器外部に取り出すことなく冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２０】
請求項１１の発明では混合酸化物燃料体を収納する長尺な容器本体と、前記混合酸化物燃料体の頂部側が配置される前記容器本体の長手方向一端側を輸送時に覆う輸送用頂部蓋とを有し、前記混合酸化物燃料体の輸送ならびに一時保管に供する輸送容器において、前記容器本体または頂部蓋に、前記容器本体の内部ガスの取り出しおよび取り入れを行うための内部ガス取出入孔を設け、この内部ガス取出入孔を前記容器本体の外部に設けた循環系冷却機構への接続を可能としたことを特徴とする混合酸化物燃料体の輸送容器を提供する。
【００２１】
請求項１２の発明では混合酸化物燃料体を輸送容器に装荷する装荷工程と、前記輸送容器を移送する移送工程と、移送前後あるいは移送途中に前記燃料体を前記輸送容器内に収納したまま待機する一時保管工程とから成る前記燃料体の輸送・一時保管方法において、前記装荷工程では、請求項１１記載の内部ガス取出入孔を容器本体あるいは頂部蓋に有する燃料輸送容器に燃料体を装荷し、前記一時保管工程では前記内部ガス取出入孔に別途循環系冷却機構を接続し、これにより前記内部ガスを強制的に外部の冷却機構に循環させて冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２２】
請求項１３の発明では混合酸化物燃料体を輸送容器に装荷する装荷工程と、前記輸送容器を移送する移送工程と、移送前後あるいは移送途中に前記燃料体を前記輸送容器内に収納したまま待機する一時保管工程とから成る前記燃料体の輸送・一時保管方法において、前記一時保管工程では、輸送容器の元来の機能維持のために設けられているドレン孔、計測用孔等の既設孔を外部の循環系冷却機構に接続し、これにより前記輸送容器の内部ガスを強制的に外部の冷却機構に循環させて冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２３】
請求項１４の発明では混合酸化物燃料体を収納する長尺な容器本体と、前記混合酸化物燃料体の頂部側が配置される前記容器本体の長手方向一端側を輸送時に覆う輸送用頂部蓋とを有し、前記混合酸化物燃料体の輸送ならびに一時保管に供する輸送容器において、前記容器本体内に燃料体収納部としてのバスケットを収納し、このバスケットの底板部に内部ガスを流通させるためのガス流通孔を設けたことを特徴とする混合酸化物燃料体の輸送容器を提供する。
【００２４】
請求項１５の発明では混合酸化物燃料体を輸送容器に装荷する装荷工程と、前記輸送容器を移送する移送工程と、移送前後あるいは移送途中に前記燃料体を前記輸送容器内に収納したまま待機する一時保管工程とから成る前記燃料体の輸送・一時保管方法において、前記装荷工程では、請求項１４記載のバスケットを内蔵した燃料輸送容器に前記燃料体を収納することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２５】
請求項１６の発明では請求項６〜１０、１２、１３または１５記載の混合酸化物燃料体の輸送・一時保管方法において、装荷工程では、窓付きで頂部に蓋が存在しない頂部開放型の燃料体保護容器に前記燃料体を収納することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２６】
請求項１７の発明では請求項６、７、１２、１３、１５または１６記載の混合酸化物燃料体の輸送・一時保管方法において、一時保管工程では、循環系冷却機構を接続する内部ガス取出入孔のうち取出孔側が上部、取入孔側が下部となるように、輸送容器を水平状態または垂直状態より傾斜させて、前記輸送容器内の内部ガスを強制的に外部の冷却機構に循環させて冷却しつつ保管することを特徴とする混合酸化物燃料体の輸送・一時保管方法を提供する。
【００２７】
【発明の実施の形態】
以下、本発明の実施形態を添付図面を参照して説明する。
【００２８】
第１実施形態（図１〜図４）
図１は、本実施形態による輸送容器を横長に配置した移送時の状態を示し、図２は、同容器を縦長に配置した一時保管時の状態を示している。
【００２９】
本実施形態の輸送容器１０は、図１に示すように、長尺な容器本体１１と、その長手方向一端側を覆う通常の輸送用頂部蓋１２とを有し、容器本体１１の外周側には放熱用のフィン１３が設けられている。輸送用容器蓋１２は容器本体１１内を密閉する構造となっている。なお、容器本体１１の底部にはドレン孔等の既存孔１４が存在している。
【００３０】
また、本実施形態の輸送容器１１では図２に示すように、冷却機能付きの一時保管用予備蓋１５が兼備されている。
【００３１】
すなわち、この一時保管用予備蓋１５は、容器本体１１の内部ガスを外方に取り出すための取り出し孔１６と、この取り出し孔１６から取り出した内部ガスを冷却する冷却機構１７と、冷却された内部ガスを再び容器本体１１内に取り入れるための取り入れ孔１８とを有している。冷却機構１７は、内部ガスを流通させる配管１９と、この配管１９に設けられた内部ガス循環用の送風器２０と、放熱器２１とを備えている。
【００３２】
このような輸送容器１０を用いてＭＯＸ燃料体の輸送及び一時保管を行う場合、装荷工程並びに図１に示す移送工程では、通常の輸送用頂部蓋１２を使用し、水平状態で移送する。この場合、容器本体１１の両端には非熱伝導性の頂部緩衝体２２ａ及び底部緩衝体２２ｂを設置する。これらの緩衝体２２ａ，２２ｂにより輸送容器１０の内部で発生した熱は長手方向には流れにくく、主に熱伝導により容器本体１１に伝わり、放熱フィン１３を介して外部に放出される。
【００３３】
また、一時保管工程では、頂部緩衝体２２ａと通常の輸送用頂部蓋１２とを取り外し、代わりに図２に示すように、冷却機構１７付きの一時保管用予備蓋１５を取り付けるとともに、輸送容器１０を垂直状態とする。
【００３４】
この状態で輸送容器１０を一時保管した場合、輸送容器１０の内部で発生した熱の一部は、主に熱伝導によって容器本体１１に伝わり、放熱フィン１３を介して外部に放出される。一方、暖められた内部ガスは輸送容器１０の内部で上昇するため、輸送容器１０の上部がより高温化し易くなるが、本実施形態においては、高温化した輸送容器１０上部の内部ガスが、取出し孔１６から送風機２０によって強制的に配管１９を介して冷却機構１７に循環し、放熱装置２１で冷却され、取り入れ孔１８より輸送容器１０内に戻る。なお、図２において、矢印ａは輸送容器１０の内部ガスの流れの方向を示し、破線矢印ｂは、冷却媒流体の流れを示している。ここで放熱装置２１は一例として、フィン付き管で内部に高温の内部ガスを流し外部に大気を送風するもの等が挙げられる。
【００３５】
従って、放熱フィン１３からの放熱に加え、内部ガスの強制循環による放熱が行なわれるので、輸送時に比較して輸送容器１０の内部をより低温化することができる。よって、輸送容器１０の内部で使用される各種部材の一時保管時の高温劣化を防止し、これらの部材の保守、点検、交換等の作業間隔を拡大することができ、全体としての輸送コストの低下を図ることができる。
【００３６】
図３は、本実施形態の変形例を示したものである。この例では、冷却機構１７で冷却した内部ガスを輸送容器１０に戻す手段として、放熱装置２１のガス出口側の配管１９を輸送容器１０の底部に存在する既設孔１４に接続してある。すなわち、高温の内部ガスを一時保管用予備蓋１５の取出し孔１６から取り出して冷却機構１７で冷却した後、容器底部の既存孔１４を介して容器底部に戻すようになっている。
【００３７】
このような構成によると、冷却されたガスが容器本体１１の底部に取り入れられた後、図示しないＭＯＸ燃料体からの熱を奪って昇温しながら上昇し、容器頂部に到達するので、輸送容器１０の内部を低温化する点で、図２の例より一層効果的な冷却作用が行なわれる。
【００３８】
また、図４は、保管場所の都合等に応じて、輸送容器１０を水平状態にして一時保管する状態を示している。このような状態での使用によると、ガス流の状態が、図２および図３の状態に比べて若干劣るが、従来技術に比べた場合には十分有効な冷却効果が得られる。
【００３９】
第２実施形態（図５）
図５は、本発明の第２実施形態を示している。
【００４０】
本実施形態の輸送容器１０では、一時保管用予備蓋１５が、容器本体１０の内部側の高温ガスから熱を直接奪い、外部に放出する機能を有している。
【００４１】
すなわち、本実施形態では、一時保管用予備蓋１５の輸送容器内部側に内向きフィン２３ａが設けられ、また外側には外向きフィン２３ｂが設けられている。そして、輸送容器１０の内部ガスを容器外部に取り出すことなく、内向きフィン２２ａで熱を奪い、外向きフィン２２ｂで容器外部に放出するようにしている。
【００４２】
このような構成の輸送容器１０を用いてＭＯＸ燃料体の輸送および一時保管を行う場合、移送工程においては、図１に示した通常の輸送容器頂部蓋２２ａを使用するが、一時保管工程においては、図５に示した一時保管用予備蓋１５を使用する。これにより、一時保管時の輸送容器１０の内部を低温化することができ、第１実施形態と略同様の効果が奏される。
【００４３】
第３実施形態（図６）
図６は本発明の第３実施形態を示している。
【００４４】
本実施形態の輸送容器１０では、一時保管用予備蓋１５に、その蓋壁を貫通して容器内部側及び外部側に突出する多数のヒートパイプ２４が設置されている。これにより、輸送容器１０の内部側の高温ガスから熱が直接奪われ、外部に放出されるようになっている。
【００４５】
このような構成を有する輸送容器１０を使用してＭＯＸ燃料体の輸送および一時保管を行う場合、移送工程では、図示しない通常の輸送容器頂部蓋を使用するが、一時保管工程では、図６に示した一時保管用予備蓋２４を使用する。これにより、一時保管時の輸送容器１０の内部を低温化することができ、第１実施形態と略同様の効果が奏される。
【００４６】
第４実施形態（図７）
図７は本発明の第４実施形態を示している。
【００４７】
本実施形態の燃料輸送容器１０では、通常の輸送用頂部蓋１２あるいは容器本体１１に開閉自在な内部ガス取出入孔２５、２６が設けてある。そして、これらの内部ガス取出入孔２５、２６に、外部の送風機２７、放熱装置２８および配管２９を有する循環系冷却機構３０が接続されている。
【００４８】
本実施形態では、燃料装荷工程、移送工程、一時保管工程のいずれの工程においても、循環系冷却機構３０に接続するための専用の内部ガス取出入孔２５、２６を有する輸送容器１０を使用する。一時保管工程においては、図７に示すように、前記専用の内部ガス取出入孔２５、２６に、送風機２６と放熱装置２８とを有する循環系冷却機構３０を接続し、輸送容器１０の内部ガスを強制的に循環して冷却する。
【００４９】
本実施形態によれば、前述した第１実施形態と同様の効果が奏されることに加え、頂部蓋１２を、一時保管時に別の予備蓋に交換する必要がないため、一時保管の作業工程が大幅に短縮できる。
【００５０】
なお、図７に示したように、輸送容器１０の底部に既存孔１４が存在する場合には、２種の前記専用の内部ガス取出入孔の一方、すなわちこの場合は内部ガス取出入孔２６の代わりに、既存孔１４を使用しても良い。
【００５１】
第５実施形態（図８、９）
図８は本発明の第５実施形態の基本構成例を示し、図９はその変形例を示している。
【００５２】
本実施形態では、ＭＯＸ燃料体の装荷工程、移送工程、一時保管工程のいずれの工程においても、輸送容器１０を使用する。ただし、一時保管工程においては、図８に示すように、輸送容器元来の機能維持のために存在するドレン孔、計測用孔等の既設孔１４ａ，１４ｂに、前記第４実施形態と同様の循環系冷却機構３０を接続し、輸送容器１０の内部ガスを強制的に循環し冷却する。
【００５３】
本実施形態によれば、既設孔使用のため冷却能力としては制限されるが、前記第３実施形態と略同様の効果が奏される。
【００５４】
なお、図８においては、取り出し孔として利用できる既設孔１４ａが頂部蓋１２に存在する場合を示したが、図９に示すように、取り出し孔として利用できる既設孔１４ｃが容器本体１１の頂部近傍に存在する場合にはこれを利用しても良い。
【００５５】
第６実施形態（図１０）
図１０は本発明の第６実施形態を示している。
【００５６】
本実施形態の輸送容器１０は、容器本体１１内に収納されるＭＯＸ燃料体収納部であるバスケット３１の底板部に、そのバスケット３１の内部空間３２と連通するガス流通孔３３が穿設されている。
【００５７】
本実施形態の燃料輸送・一時保管法では、ＭＯＸ燃料体の装荷工程、移送工程および一時保管工程のいずれの工程においても、前記輸送容器１０を使用するものであり、一時保管工程において、図１０に示すように、外部の循環系冷却機構３０に接続し、内部ガスを強制的に循環し冷却しようとするとき、特にその効果を発揮する。
【００５８】
すなわち、冷却機構３０で冷却され、輸送容器底部に戻された内部ガスが、バスケット３１の内部空間３２の存在により、図示しないＭＯＸ燃料体が収納されているバスケット３１の内部空間３２に容易に流入することができる。従って、冷却された内部ガスが燃料体と直接接触し易くなり、特に燃料体の低温化に著しい効果を発揮する。
【００５９】
第７実施形態（図１１）
図１１は本発明の第７実施形態を示している。
【００６０】
本実施形態では、ＭＯＸ燃料体の輸送及び一時保管法では、ＭＯＸ燃料体の輸送容器１０への装荷工程で、ＭＯＸ燃料体を窓部３４付きで頂部３５に蓋の存在しない頂部開放型保護容器３６に収納した上で、バスケット３１の内部空間３２に装荷するものである。
【００６１】
一時保管工程では、一例として図示したように、輸送容器１０は外部の循環系冷却機構３０に接続され、内部ガスが強制的に循環して冷却される。冷却された内部ガスは、保護容器３６の窓部３４から保護容器３６の内部に流入し、図示しないＭＯＸ燃料体と直接接して熱を奪いながら燃料保護容器３６内を上昇し、蓋の存在しない頂部３５より保護容器３６の外部へ流出し、再び循環系冷却機構３０へと循環する。
【００６２】
頂部に蓋が存在する保護容器を使用した場合には、高温の内部ガスが保護容器頂部に滞留し易いため、ＭＯＸ燃料体の上部が高温化し易いが、本実施形態によれば、このような事象の発生を避け、ＭＯＸ燃料体の全長に亘って低温化することができる。
【００６３】
第８実施形態（図１２）
図１２は本発明の第８実施形態を示している。
【００６４】
本実施形態では、ＭＯＸ燃料体の輸送及び一時保管法を行う場合、一時保管工程において、循環系冷却機構３０を接続する内部ガス取出入孔としての既設孔１４ａ、１４ｂのうちの取出孔１４ａ側が上部、取入孔１４ｂ側が下部となるように、輸送容器１０を水平状態あるいは垂直状態より傾斜させて、輸送容器１０の内部ガスを強制的に外部の冷却機構３０に循環させて冷却しつつ保管するものである。
【００６５】
一時保管場所の設備によっては、横置き状態で移送されてきた燃料輸送容器１０をそのままの状態で保管したいという事情もあり得る。このような場合、本実施形態では上述したように、輸送容器１０を傾斜状態とすることにより、輸送容器１０の内部ガスが容器内部で流れ易くなり、容器内部の冷却効果を向上することができる。
【００６６】
【発明の効果】
以上で説明したように、本発明の請求項１、２、３、４、５、１１、１４に係る混合酸化物燃料体の輸送容器によれば一時保管時に輸送容器内部を低温化し易く、その内部で使用されている各種部材の一時保管時の高温劣化を防ぎ易く、これら部材の保守、点検、交換間隔を拡大でき、全体輸送コストの低減を図ることができる。
【００６７】
また、本発明の請求項６、７、８、９、１０、１２、１３、１５、１６、１７に係る混合酸化物燃料体の輸送・一時保管方法によれば、一時保管時に輸送容器内部をより効率的に低温化し、その内部で使用されている各種部材の一時保管時の高温劣化を防ぎ易く、これら部材の保守、点検、交換間隔を拡大でき、全体輸送コストの低減を図ることができる。
【図面の簡単な説明】
【図１】本発明の第１実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図２】本発明の第１実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図３】本発明の第１実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図４】本発明の第１実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図５】本発明の第２実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図６】本発明の第３実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図７】本発明の第４実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図８】本発明の第４実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図９】本発明の第５実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図１０】本発明の第６実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図１１】本発明の第７実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図１２】本発明の第８実施形態におけるＭＯＸ燃料体の輸送容器を示す断面図。
【図１３】従来の輸送容器を示す断面図。
【符号の説明】
１輸送容器
２容器本体
３頂部蓋
４フィン
５既設孔
６底部緩衝体
７頂部緩衝体
１０輸送容器
１１容器本体
１２輸送用頂部蓋
１３フィン
１４（１４ａ，１４ｂ）既存孔（内部ガス取出入孔）
１５一時保管用予備蓋
１６取り出し孔
１７冷却機構
１８取り入れ孔
１９配管
２０送風機
２１放熱器
２２ａ頂部緩衝体
２２ｂ底部緩衝体
２３ａ内向きフィン
２３ｂ外向きフィン
２４ヒートパイプ
２５，２６内部ガス取出入孔
２７送風機
２８放熱装置
２９配管
３０循環系冷却機構
３１バスケット
３２内部空間
３３ガス流通孔
３４窓部
３５頂部
３６頂部開放型保護容器[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transport container, a transport method, and a temporary storage method used when transporting an exothermic mixed oxide fuel body (MOX fuel body) from, for example, a fuel processing facility to a nuclear power generation facility.
[0002]
[Prior art]
An MOX fuel body in which plutonium oxide and uranium oxide are mixed has heat generation unlike a fuel body made of uranium oxide. As an example of such an exothermic fuel body, a transport and storage container for spent fuel having a structure shown in, for example, JP-A-57-179699 has been known.
[0003]
FIG. 13 illustrates the configuration of such a conventional transport container. The transport container 1 is composed of a long container body 2 and a top lid 3 that covers one end in the longitudinal direction, and contains a basket for storing a MOX fuel body (not shown). A fin 4 for heat dissipation is provided on the outer peripheral side of the container body 2, and there are existing holes 5 such as drain holes for discharging the internal fluid and some existing holes for measurement (not shown) at the bottom. Yes. Similarly, several existing holes exist in the top lid 3.
[0004]
At the time of transportation, a bottom buffer body 6 and a top buffer body 7 which are detachable from the bottom and top of the container body 2 and are mainly made of a non-thermally conductive member are installed. Further, the top lid 3 and the like are configured such that a structure that is weak in strength, such as a pipe protruding from the lid wall, cannot be installed. Therefore, the bottom of the container body 2 and the top cover 3 for normal transportation do not necessarily have an effective heat dissipation function from the inside of the container to the outside. Therefore, the heat generated from the fuel body during transportation is transmitted to the container body 2 from an internal structure such as a basket (not shown) mainly by heat conduction, and is released to the outside by the radiation fins 4, but is made of a non-thermal conductive material. From the viewpoint of the presence of the bottom buffer body 6 and the top buffer body 7 and the above-described strength, heat is not easily radiated from the normal transport top lid 3 or the bottom of the container body 2.
[0005]
In the transportation of a new MOX fuel body, various measures against vibration are required unlike the transportation of a spent fuel body. For example, the MOX fuel body is put in a protective container (not shown), and the protective container is further stored in a basket and then transported in the transport container 1. At this time, the MOX fuel body is placed in the protective container, and the protective container is placed in the basket. Each must be tightened and restrained. In addition, there is a desire to avoid direct contact between the MOX fuel body and other metals. For these reasons, in transporting MOX fuel bodies, various materials that cannot be used for a sufficiently long time, ie semipermanently, at high temperatures, such as rubber materials, resin materials, or metal parts of sliding parts such as clamping devices, are transported. There is a situation that it must be used inside the container. Therefore, these members must be regularly inspected during the period of use and replaced if necessary.
[0006]
By the way, when the transportation process of the MOX fuel body is assumed, it can be easily estimated that the MOX fuel body is not stored in the transportation container only during the transportation period between the transportation starting point and the destination. . For example, in a state where the MOX fuel body is stored in the transport container, such as a standby period from when the MOX fuel body is loaded to the transport container until the start of transfer, or a standby period until the MOX fuel body is taken out after reaching the destination. The so-called temporary storage period will always occur. The temporary storage period will vary depending on the transport conditions, but in some cases it may be equal to or longer than the transfer period. If the temporary storage period is prolonged with respect to the transfer period, the high-temperature deterioration of the above-mentioned member proceeds accordingly and the life is shortened.
[0007]
In the conventional fuel transport container and the fuel transport and temporary storage method, there is no example in which measures are taken in consideration of the deterioration of the internal member during the temporary storage described above.
[0008]
[Problems to be solved by the invention]
In the transportation of the MOX fuel body, there is a situation in which various materials that cannot be used for a sufficiently long time, that is, semipermanently at high temperatures, must be used inside the transportation container. Therefore, if the period of temporary storage is prolonged and the period of the high temperature state is prolonged, the temperature of these members is deteriorated accordingly, and the life is shortened.
[0009]
The present invention has been made paying attention to the above circumstances, and its purpose is to prevent high temperature deterioration during temporary storage of the member by lowering the temperature inside the transport container during temporary storage, An object of the present invention is to provide a transport container and a transport / temporary storage method for a mixed oxide fuel body that can increase the maintenance, inspection, and replacement intervals of these members and can reduce the overall transport cost.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, there is provided a long container body that contains a mixed oxide fuel body, and one longitudinal end side of the container body on which a top side of the mixed oxide fuel body is disposed. A transportation top cover for transporting and temporarily storing the mixed oxide fuel body, and a cover with a cooling function as a temporary storage preliminary cover in addition to the transportation top cover. Provided is a transport container for a mixed oxide fuel body characterized in that it is also used.
[0011]
According to a second aspect of the present invention, in the transport container for the mixed oxide fuel body according to the first aspect, the temporary storage auxiliary lid is taken out from the take-out hole for taking out the internal gas of the container body to the outside, and the take-out hole. A cooling mechanism for cooling the internal gas; and an intake hole for taking the cooled internal gas into the container body again, thereby forcing the internal gas of the container body to the outside. A transport container for a mixed oxide fuel body that can be circulated and cooled.
[0012]
According to a third aspect of the present invention, in the transport container for the mixed oxide fuel body according to the first aspect, the temporary storage preliminary lid has a function of directly taking heat from the internal gas of the container body and releasing it to the outside. Provided is a transport container for a mixed oxide fuel body that can cool an internal gas of a main body without circulating it outside.
[0013]
According to a fourth aspect of the present invention, in the transport container for the mixed oxide fuel body according to the first aspect, the temporary storage auxiliary lid has inward fins facing the inner side of the container body and faces the outer side of the container body. A transport container for a mixed oxide fuel body having outward fins is provided.
[0014]
According to a fifth aspect of the present invention, in the transport container for the mixed oxide fuel body according to the first aspect, the preliminary storage pre-cover has a plurality of heat pipes projecting to the inner side and the outer side of the container body. Provide a shipping container.
[0015]
According to the sixth aspect of the present invention, a loading process for loading the mixed oxide fuel body into the transport container, a transport process for transporting the transport container, and waiting while the fuel body is stored in the transport container before, during or during the transport. In the method of transporting and temporarily storing the mixed oxide fuel body comprising the temporary storage step, the fuel loading is carried out in the transporting container that also has a preliminary storage cover with a cooling function in addition to the top cover for transport. In the transfer step, the original transport top lid is used as the top lid of the transport container. In the temporary storage step, the original transport top lid is replaced with a temporary storage spare lid with a cooling function. In addition, the present invention provides a method for transporting and temporarily storing a mixed oxide fuel body, characterized in that the internal gas in the transport container is stored while being cooled with the temporary storage preliminary lid.
[0016]
According to a seventh aspect of the present invention, in the transport / temporary storage method of the mixed oxide fuel assembly according to the sixth aspect, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to the second aspect, Provided is a method for transporting and temporarily storing a mixed oxide fuel body, wherein internal gas is forcedly circulated to an external cooling mechanism and stored while being cooled.
[0017]
According to an eighth aspect of the present invention, in the transport / temporary storage method of the mixed oxide fuel assembly according to the sixth aspect, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to the third aspect. Provided is a method for transporting and temporarily storing a mixed oxide fuel body, wherein internal gas is stored while being cooled without being taken out of a transport container.
[0018]
In a ninth aspect of the invention, in the transport / temporary storage method of the mixed oxide fuel assembly according to the sixth aspect, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to the fourth aspect, Provided is a method for transporting and temporarily storing a mixed oxide fuel body, wherein internal gas is stored while being cooled without being taken out of a transport container.
[0019]
According to a tenth aspect of the present invention, in the transport / temporary storage method of the mixed oxide fuel assembly according to the sixth aspect, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to the fifth aspect, Provided is a method for transporting and temporarily storing a mixed oxide fuel body, wherein internal gas is stored while being cooled without being taken out of a transport container.
[0020]
According to an eleventh aspect of the present invention, a long container body that houses a mixed oxide fuel body, a transport top lid that covers one longitudinal end of the container body on which the top side of the mixed oxide fuel body is disposed during transportation, In the transport container for transporting and temporarily storing the mixed oxide fuel body, the container body or the top lid is provided with an internal gas inlet / outlet hole for taking out and taking in the internal gas of the container body. The present invention also provides a transport container for a mixed oxide fuel body, characterized in that it can be connected to a circulation system cooling mechanism in which the internal gas take-in / out hole is provided outside the container body.
[0021]
In the invention of claim 12, a loading process for loading the mixed oxide fuel body into the transport container, a transport process for transporting the transport container, and waiting while the fuel body is stored in the transport container before, during or during the transport. In the method for transporting and temporarily storing the fuel body comprising the temporary storage step, the fuel body is loaded into the fuel transport container having the internal gas inlet / outlet hole in the container body or the top lid in the loading step. In the temporary storage step, a circulation system cooling mechanism is separately connected to the internal gas inlet / outlet hole, whereby the internal gas is forcedly circulated to an external cooling mechanism and stored while being cooled. A method for transporting and temporarily storing oxide fuel bodies is provided.
[0022]
In the invention of claim 13, a loading process for loading the mixed oxide fuel body into the transport container, a transport process for transporting the transport container, and waiting while the fuel body is stored in the transport container before, during or during the transport. In the method of transporting and temporarily storing the fuel body comprising the temporary storage step, in the temporary storage step, existing holes such as drain holes and measurement holes provided for maintaining the original function of the transport container are provided. Transportation / temporary storage of a mixed oxide fuel body characterized in that it is connected to an external circulation system cooling mechanism, whereby the internal gas of the transport container is forcibly circulated to the external cooling mechanism and stored while being cooled. Provide a method.
[0023]
In a fourteenth aspect of the present invention, a long container body that houses a mixed oxide fuel body, and a transport top lid that covers one longitudinal end of the container body on which the top side of the mixed oxide fuel body is disposed during transportation; A transport container for transporting and temporarily storing the mixed oxide fuel body, wherein a basket as a fuel body storage portion is stored in the container body, and an internal gas is circulated through the bottom plate portion of the basket. Provided is a transport container for a mixed oxide fuel body, wherein a gas flow hole is provided.
[0024]
In the invention of claim 15, a loading process for loading the mixed oxide fuel body into a transport container, a transport process for transporting the transport container, and waiting while the fuel body is stored in the transport container before, during or during the transport. 15. A method for transporting and temporarily storing a fuel body comprising a temporary storage step, wherein the fuel body is housed in a fuel transport container having a built-in basket according to claim 14, in the loading step. Provide transportation and temporary storage methods for fuel assemblies.
[0025]
According to a sixteenth aspect of the present invention, in the method for transporting and temporarily storing the mixed oxide fuel body according to the sixth to tenth, twelfth, thirteenth and fifteenth aspects, the top opening type fuel having a window and no top cover in the loading process. Provided is a method for transporting and temporarily storing a mixed oxide fuel body, wherein the fuel body is housed in a body protection container.
[0026]
The invention according to claim 17 is the method for transporting and temporarily storing the mixed oxide fuel body according to claim 6, 7, 12, 13, 15 or 16, wherein in the temporary storage step, the internal gas extraction / entry connecting the circulation system cooling mechanism is performed. The transport container is inclined from the horizontal or vertical state so that the extraction hole side is the upper part and the intake hole side is the lower part of the holes, and the internal gas in the transport container is forcibly circulated to the external cooling mechanism. Provided is a method for transporting and temporarily storing a mixed oxide fuel body, which is stored while being cooled.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0028]
1st Embodiment (FIGS. 1-4)
FIG. 1 shows a state during transfer in which the transport container according to the present embodiment is arranged horizontally, and FIG. 2 shows a state during temporary storage where the container is arranged vertically.
[0029]
As shown in FIG. 1, the transport container 10 of the present embodiment includes a long container body 11 and a normal transport top lid 12 that covers one end side in the longitudinal direction. Are provided with fins 13 for heat dissipation. The transport container lid 12 has a structure for sealing the inside of the container body 11. An existing hole 14 such as a drain hole is present at the bottom of the container body 11.
[0030]
Further, as shown in FIG. 2, the transport container 11 of the present embodiment also has a temporary storage spare lid 15 with a cooling function.
[0031]
That is, the temporary storage preliminary lid 15 includes a take-out hole 16 for taking out the internal gas of the container body 11 to the outside, a cooling mechanism 17 for cooling the internal gas taken out from the take-out hole 16, and a cooled internal An intake hole 18 is provided for taking the gas into the container body 11 again. The cooling mechanism 17 includes a pipe 19 through which internal gas is circulated, a blower 20 for circulating internal gas provided in the pipe 19, and a radiator 21.
[0032]
When transporting and temporarily storing the MOX fuel body using such a transport container 10, in the loading process and the transport process shown in FIG. 1, a normal transport top lid 12 is used and transported in a horizontal state. In this case, a non-thermally conductive top buffer 22a and bottom buffer 22b are installed at both ends of the container body 11. The heat generated inside the transport container 10 by these buffer bodies 22a and 22b is unlikely to flow in the longitudinal direction, is mainly transmitted to the container body 11 by heat conduction, and is released to the outside through the radiation fins 13.
[0033]
Further, in the temporary storage step, the top buffer 22a and the normal transport top lid 12 are removed, and instead, as shown in FIG. 2, a temporary storage spare lid 15 with a cooling mechanism 17 is attached and the transport container 10 is attached. Is in a vertical state.
[0034]
When the transport container 10 is temporarily stored in this state, a part of the heat generated inside the transport container 10 is mainly transmitted to the container body 11 by heat conduction, and is released to the outside through the radiation fins 13. On the other hand, since the warmed internal gas rises inside the transport container 10, the upper part of the transport container 10 is likely to be heated to a higher temperature. However, in this embodiment, the heated internal gas at the upper part of the transport container 10 is taken out. The air is forced to circulate from the hole 16 to the cooling mechanism 17 via the pipe 19 by the blower 20, is cooled by the heat radiating device 21, and returns to the inside of the transport container 10 through the intake hole 18. In FIG. 2, arrow a indicates the direction of the internal gas flow in the transport container 10, and broken line arrow b indicates the flow of the coolant fluid. Here, as an example, the heat dissipating device 21 may be a finned tube that flows high-temperature internal gas inside and blows air to the outside.
[0035]
Therefore, in addition to the heat radiation from the heat radiation fins 13, the heat radiation by the forced circulation of the internal gas is performed, so that the inside of the transport container 10 can be further cooled as compared with the time of transport. Therefore, it is possible to prevent high temperature deterioration during temporary storage of various members used inside the transport container 10, and to increase the work interval of maintenance, inspection, replacement, etc. of these members, and to reduce the transport cost as a whole. Reduction can be achieved.
[0036]
FIG. 3 shows a modification of the present embodiment. In this example, as a means for returning the internal gas cooled by the cooling mechanism 17 to the transport container 10, a pipe 19 on the gas outlet side of the heat radiating device 21 is connected to the existing hole 14 existing at the bottom of the transport container 10. That is, the high-temperature internal gas is taken out from the take-out hole 16 of the temporary storage auxiliary lid 15 and cooled by the cooling mechanism 17 and then returned to the container bottom through the existing hole 14 in the container bottom.
[0037]
According to such a configuration, after the cooled gas is taken into the bottom of the container main body 11, the temperature rises while taking away heat from the MOX fuel body (not shown) and reaches the top of the container. The cooling operation is more effective than the example of FIG.
[0038]
FIG. 4 shows a state in which the transport container 10 is horizontally stored in accordance with the convenience of the storage location. When used in such a state, the state of the gas flow is slightly inferior to the state of FIGS. 2 and 3, but a sufficiently effective cooling effect is obtained when compared with the prior art.
[0039]
Second Embodiment (FIG. 5)
FIG. 5 shows a second embodiment of the present invention.
[0040]
In the transport container 10 of the present embodiment, the temporary storage spare lid 15 has a function of directly taking heat from the high-temperature gas inside the container body 10 and releasing it to the outside.
[0041]
That is, in this embodiment, the inward fins 23a are provided on the transport container inside side of the temporary storage spare lid 15, and the outward fins 23b are provided on the outer side. Then, without taking out the internal gas of the transport container 10 to the outside of the container, heat is taken away by the inward fins 22a and discharged to the outside of the container by the outward fins 22b.
[0042]
When transporting and temporarily storing the MOX fuel body using the transport container 10 having such a configuration, the normal transport container top lid 22a shown in FIG. 1 is used in the transfer process, but in the temporary storage process, The temporary storage spare lid 15 shown in FIG. 5 is used. Thereby, the inside of the transport container 10 at the time of temporary storage can be reduced in temperature, and the effect substantially the same as 1st Embodiment is show | played.
[0043]
Third Embodiment (FIG. 6)
FIG. 6 shows a third embodiment of the present invention.
[0044]
In the transport container 10 of the present embodiment, a large number of heat pipes 24 that pass through the cover wall and protrude toward the inside and outside of the container are installed in the temporary storage auxiliary lid 15. Thereby, heat is directly taken from the high-temperature gas inside the transport container 10 and released to the outside.
[0045]
When transporting and temporarily storing the MOX fuel body using the transport container 10 having such a configuration, a normal transport container top lid (not shown) is used in the transfer process, but in the temporary storage process, FIG. The temporary storage reserve cover 24 shown is used. Thereby, the inside of the transport container 10 at the time of temporary storage can be reduced in temperature, and the effect substantially the same as 1st Embodiment is show | played.
[0046]
Fourth embodiment (FIG. 7)
FIG. 7 shows a fourth embodiment of the present invention.
[0047]
In the fuel transport container 10 of the present embodiment, the normal transport top lid 12 or the container body 11 is provided with internal gas extraction holes 25 and 26 that can be opened and closed. A circulation system cooling mechanism 30 having an external blower 27, a heat radiating device 28, and a pipe 29 is connected to the internal gas extraction holes 25 and 26.
[0048]
In the present embodiment, the transport container 10 having the dedicated internal gas inlet / outlet holes 25 and 26 for connection to the circulation system cooling mechanism 30 is used in any of the fuel loading process, the transfer process, and the temporary storage process. . In the temporary storage step, as shown in FIG. 7, a circulation system cooling mechanism 30 having a blower 26 and a heat radiating device 28 is connected to the dedicated internal gas take-in / out holes 25, 26, and the internal gas of the transport container 10 is Forcibly circulate and cool.
[0049]
According to the present embodiment, in addition to the same effects as those of the first embodiment described above, it is not necessary to replace the top lid 12 with another spare lid at the time of temporary storage. Can be greatly shortened.
[0050]
As shown in FIG. 7, when the existing hole 14 exists at the bottom of the transport container 10, one of the two types of dedicated internal gas inlet / outlet holes, that is, in this case, the internal gas inlet / outlet hole 26 is provided. Instead of the above, the existing hole 14 may be used.
[0051]
Fifth embodiment (FIGS. 8 and 9)
FIG. 8 shows a basic configuration example of the fifth embodiment of the present invention, and FIG. 9 shows a modification thereof.
[0052]
In this embodiment, the transport container 10 is used in any of the MOX fuel body loading process, transfer process, and temporary storage process. However, in the temporary storage step, as shown in FIG. 8, the existing holes 14 a and 14 b such as drain holes and measurement holes existing for maintaining the original function of the transport container are similar to those in the fourth embodiment. A circulation system cooling mechanism 30 is connected to forcibly circulate and cool the internal gas of the transport container 10.
[0053]
According to the present embodiment, the cooling capacity is limited due to the use of the existing holes, but substantially the same effect as the third embodiment is achieved.
[0054]
8 shows a case where the existing hole 14a that can be used as a take-out hole is present in the top lid 12, but as shown in FIG. 9, the existing hole 14c that can be used as a take-out hole is near the top of the container body 11. You may use this if it exists.
[0055]
Sixth embodiment (FIG. 10)
FIG. 10 shows a sixth embodiment of the present invention.
[0056]
In the transport container 10 of the present embodiment, a gas flow hole 33 communicating with the internal space 32 of the basket 31 is formed in the bottom plate portion of the basket 31 that is a MOX fuel body storage portion stored in the container main body 11. Yes.
[0057]
In the fuel transportation / temporary storage method of the present embodiment, the transport container 10 is used in any of the MOX fuel body loading process, the transfer process, and the temporary storage process. In the temporary storage process, FIG. As shown in FIG. 4, the effect is particularly exerted when the internal gas is connected to the external circulation system cooling mechanism 30 to forcibly circulate and cool the internal gas.
[0058]
That is, the internal gas cooled by the cooling mechanism 30 and returned to the bottom of the transport container easily flows into the internal space 32 of the basket 31 in which the MOX fuel body (not shown) is accommodated due to the presence of the internal space 32 of the basket 31. can do. Therefore, the cooled internal gas is easily brought into direct contact with the fuel body, and exhibits a remarkable effect particularly in reducing the temperature of the fuel body.
[0059]
Seventh embodiment (FIG. 11)
FIG. 11 shows a seventh embodiment of the present invention.
[0060]
In the present embodiment, in the MOX fuel body transport and temporary storage method, in the loading process of the MOX fuel body into the transport container 10, the MOX fuel body is provided with the window 34 and the top open-type protective container without the top 35 having a lid. After being stored in 36, it is loaded into the internal space 32 of the basket 31.
[0061]
In the temporary storage process, as illustrated as an example, the transport container 10 is connected to an external circulation system cooling mechanism 30, and the internal gas is forcibly circulated and cooled. The cooled internal gas flows into the inside of the protective container 36 from the window 34 of the protective container 36, rises in the fuel protective container 36 while directly contacting a MOX fuel body (not shown), and has no lid. It flows out of the protective container 36 from the top 35 and circulates again to the circulation system cooling mechanism 30.
[0062]
When a protective container having a lid at the top is used, high temperature internal gas tends to stay at the top of the protective container, so that the upper part of the MOX fuel body is likely to be heated to a high temperature. The occurrence of an event can be avoided, and the temperature can be lowered over the entire length of the MOX fuel body.
[0063]
Eighth embodiment (FIG. 12)
FIG. 12 shows an eighth embodiment of the present invention.
[0064]
In the present embodiment, when the MOX fuel body is transported and temporarily stored, in the temporary storage step, the extraction hole 14a side of the existing holes 14a and 14b as internal gas extraction / intake holes connecting the circulation system cooling mechanism 30 is The transport container 10 is inclined from the horizontal state or the vertical state so that the upper part and the intake hole 14b side are the lower part, and the internal gas of the transport container 10 is forcedly circulated to the external cooling mechanism 30 and stored while being cooled. To do.
[0065]
Depending on the equipment in the temporary storage place, there may be a situation where it is desired to store the fuel transport container 10 that has been transported in the horizontal state as it is. In such a case, as described above, in this embodiment, by making the transport container 10 in an inclined state, the internal gas of the transport container 10 can easily flow inside the container, and the cooling effect inside the container can be improved. .
[0066]
【The invention's effect】
As described above, according to the transport container for mixed oxide fuel bodies according to claims 1, 2, 3, 4, 5, 11, and 14 of the present invention, it is easy to lower the temperature inside the transport container during temporary storage. It is easy to prevent high temperature deterioration during temporary storage of various members used inside, the maintenance, inspection and replacement intervals of these members can be increased, and the overall transportation cost can be reduced.
[0067]
According to the sixth, seventh, eighth, ninth, tenth, twelfth, thirteenth, fifteenth, sixteenth and seventeenth aspect of the present invention, the mixed oxide fuel assembly is transported and temporarily stored. It is possible to lower the temperature more efficiently, easily prevent high-temperature deterioration during temporary storage of various components used in the interior, increase the maintenance, inspection and replacement intervals of these components, and reduce the overall transportation cost. .
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a MOX fuel body transport container according to a first embodiment of the present invention.
FIG. 2 is a cross-sectional view showing a MOX fuel body transport container according to the first embodiment of the present invention.
FIG. 3 is a cross-sectional view showing a MOX fuel body transport container according to the first embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a MOX fuel body transport container according to the first embodiment of the present invention.
FIG. 5 is a sectional view showing a MOX fuel body transport container according to a second embodiment of the present invention.
FIG. 6 is a cross-sectional view showing a MOX fuel body transport container according to a third embodiment of the present invention.
FIG. 7 is a cross-sectional view showing a MOX fuel body transport container according to a fourth embodiment of the present invention.
FIG. 8 is a cross-sectional view showing a MOX fuel body transport container according to a fourth embodiment of the present invention.
FIG. 9 is a cross-sectional view showing a transport container for MOX fuel bodies according to a fifth embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a MOX fuel body transport container according to a sixth embodiment of the present invention.
FIG. 11 is a sectional view showing a MOX fuel body transport container according to a seventh embodiment of the present invention.
FIG. 12 is a sectional view showing a transport container for MOX fuel bodies according to an eighth embodiment of the present invention.
FIG. 13 is a cross-sectional view showing a conventional transport container.
[Explanation of symbols]
1 Transport container
2 Container body
3 Top lid
4 Fin
5 Existing holes
6 Bottom shock absorber
7 Top cushion
10 Transport container
11 Container body
12 Transport top lid
13 Fin
14 (14a, 14b) Existing hole (internal gas outlet / inlet hole)
15 Spare lid for temporary storage
16 Removal hole
17 Cooling mechanism
18 intake hole
19 Piping
20 Blower
21 Heatsink
22a Top cushion
22b Bottom shock absorber
23a Inward fin
23b outward fin
24 heat pipe
25, 26 Internal gas inlet / outlet
27 Blower
28 Heat dissipation device
29 Piping
30 Circulation system cooling mechanism
31 baskets
32 Internal space
33 Gas distribution hole
34 Window
35 Top
36 Top Open Type Protective Container

Claims

A long container body that contains the mixed oxide fuel body, and a transport top lid that covers one end side in the longitudinal direction of the container body in which the top side of the mixed oxide fuel body is disposed during transportation, and the mixing A transport container for transporting and temporarily storing an oxide fuel body, wherein the transporting of the mixed oxide fuel body is characterized in that, in addition to the top cover for transport, a lid with a cooling function is provided as a preliminary cover for temporary storage. container.

2. The transport container for a mixed oxide fuel assembly according to claim 1, wherein the temporary storage preliminary cover cools the internal gas taken out from the take-out hole for taking out the internal gas from the container main body to the outside. A cooling mechanism and an intake hole for taking the cooled internal gas into the container body again, thereby forcibly circulating the internal gas of the container body to the external cooling mechanism for cooling A transport container for a mixed oxide fuel body that makes it possible.

2. The transport container for a mixed oxide fuel assembly according to claim 1, wherein the temporary storage preliminary lid has a function of directly taking heat from the internal gas of the container main body and releasing the heat to the outside, A transport container for a mixed oxide fuel body that can be cooled without being circulated.

The transport container for a mixed oxide fuel assembly according to claim 1, wherein the preliminary storage preliminary cover has inward fins facing inward of the container body and outward fins facing out of the container body. Transport container for oxide fuel bodies.

2. The transport container for a mixed oxide fuel assembly according to claim 1, wherein the temporary storage preliminary lid has a large number of heat pipes protruding to the inner side and the outer side of the container body.

A loading step of loading a mixed oxide fuel body into a transport container; a transporting step of transporting the transport container; and a temporary storage step of waiting while the fuel body is stored in the transport container before, during or during the transport. In the transport / temporary storage method of the mixed oxide fuel body, in the loading step, the fuel body is loaded into the transport container that also has a preliminary storage cover with a cooling function in addition to the top cover for transport, In the transfer step, the original transport top lid is used as the top lid of the transport container, and in the temporary storage step, the original transport top lid is replaced with a temporary storage spare lid with a cooling function. A method for transporting and temporarily storing a mixed oxide fuel body, characterized in that the internal gas of the transport container is stored while being cooled with a lid.

In the method for transporting and temporarily storing the mixed oxide fuel body according to claim 6, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to claim 2, and the internal gas of the transport container is forcibly changed. A method for transporting and temporarily storing a mixed oxide fuel body, wherein the mixed oxide fuel body is stored while being cooled by being circulated through an external cooling mechanism.

7. The method for transporting and temporarily storing a mixed oxide fuel body according to claim 6, wherein in the temporary storage step, the top cover for transportation is replaced with the preliminary lid for temporary storage according to claim 3, and the internal gas of the transport container is transferred to the outside of the transport container. A method for transporting and temporarily storing a mixed oxide fuel body, wherein the mixed oxide fuel body is stored while being cooled without being taken out.

7. The method for transporting and temporarily storing a mixed oxide fuel body according to claim 6, wherein in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to claim 4, and the internal gas of the transport container is transferred to the outside of the transport container. A method for transporting and temporarily storing a mixed oxide fuel body, wherein the mixed oxide fuel body is stored while being cooled without being taken out.

In the method for transporting and temporarily storing the mixed oxide fuel body according to claim 6, in the temporary storage step, the top cover for transport is replaced with the preliminary cover for temporary storage according to claim 5, and the internal gas of the transport container is transferred to the outside of the transport container. A method for transporting and temporarily storing a mixed oxide fuel body, wherein the mixed oxide fuel body is stored while being cooled without being taken out.

A long container body that contains the mixed oxide fuel body, and a transport top lid that covers one end side in the longitudinal direction of the container body in which the top side of the mixed oxide fuel body is disposed during transportation, and the mixing In a transport container for transport and temporary storage of an oxide fuel body, the container body or top lid is provided with an internal gas inlet / outlet hole for taking out and taking in the internal gas of the container body. A transport container for a mixed oxide fuel body, characterized in that it can be connected to a circulation system cooling mechanism in which holes are provided outside the container body.

A loading step of loading a mixed oxide fuel body into a transport container; a transporting step of transporting the transport container; and a temporary storage step of waiting while the fuel body is housed in the transport container before, during or during the transport. In the fuel body transport / temporary storage method, in the loading step, the fuel body is loaded into a fuel transport container having an internal gas inlet / outlet hole in a container body or a top lid according to claim 11, and in the temporary storage step, Transporting a mixed oxide fuel body, wherein a circulation system cooling mechanism is separately connected to the internal gas outlet / inlet hole, whereby the internal gas is forcibly circulated to an external cooling mechanism and stored while being cooled. -Temporary storage method.

A loading step of loading a mixed oxide fuel body into a transport container; a transporting step of transporting the transport container; and a temporary storage step of waiting while the fuel body is housed in the transport container before, during or during the transport. In the fuel body transport / temporary storage method, in the temporary storage step, existing holes such as drain holes and measurement holes provided for maintaining the original function of the transport container are replaced with an external circulation system cooling mechanism. A method for transporting and temporarily storing a mixed oxide fuel body, characterized in that the internal gas in the transport container is forcedly circulated to an external cooling mechanism and stored while being cooled.

A long container body that contains the mixed oxide fuel body, and a transport top lid that covers one end side in the longitudinal direction of the container body in which the top side of the mixed oxide fuel body is disposed during transportation, and the mixing In a transport container used for transport and temporary storage of oxide fuel bodies, a basket as a fuel body housing portion is housed in the container body, and a gas circulation hole is provided in the bottom plate portion of the basket to circulate internal gas. A transport container for mixed oxide fuel bodies.

A loading step of loading a mixed oxide fuel body into a transport container; a transporting step of transporting the transport container; and a temporary storage step of waiting while the fuel body is housed in the transport container before, during or during the transport. 15. The transport / temporary storage method for a mixed oxide fuel body according to claim 14, wherein in the loading step, the fuel body is housed in a fuel transport container having a basket built therein. Storage method.

16. The method for transporting and temporarily storing a mixed oxide fuel body according to claim 6, 10, 12, 13, or 15, wherein, in the loading step, the fuel is placed in a top open type fuel body protective container with a window and no top cover. A method for transporting and temporarily storing a mixed oxide fuel body, wherein the body is stored.

The method for transporting and temporarily storing a mixed oxide fuel body according to claim 6, 7, 12, 13, 15 or 16, wherein in the temporary storage step, the extraction hole side of the internal gas extraction / inlet holes connecting the circulation system cooling mechanism is The transport container is inclined from the horizontal state or the vertical state so that the upper part and the intake hole side are the lower part, and the internal gas in the transport container is forcibly circulated to an external cooling mechanism and stored while being cooled. A method for transporting and temporarily storing mixed oxide fuel bodies characterized by the above.