JP3833417B2

JP3833417B2 - Cooling water circulation system

Info

Publication number: JP3833417B2
Application number: JP19132999A
Authority: JP
Inventors: 研二浦井
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1999-07-06
Filing date: 1999-07-06
Publication date: 2006-10-11
Anticipated expiration: 2019-07-06
Also published as: JP2001021272A

Description

【０００１】
【発明の属する技術分野】
本発明は、火力発電所、原子力発電所、コンバインドサイクル発電所等の蒸気タービンの復水器を有する発電プラントにおいて、循環水ポンプによって昇圧された冷却水を復水器に供給し、復水器にて蒸気タービンからの排気蒸気を凝縮することによって熱交換されて温度上昇する復水器冷却用の冷却水の循環システムに関するものである。
【０００２】
【従来の技術】
発電プラントにおける復水器冷却用の冷却水の循環システムの一例を図６に示す。冷却に用いられる循環水として海水または河川水を用いる場合、図６のように構成された循環システムを、循環水（冷却水）は海または河川に設けられた取水口１から循環水ポンプ２にて昇圧され復水器３の入口側の第一の循環水路４を通り、復水器３に入る。その後、復水器３を出て、復水器出口側の第二の循環水路５を通り、放水口６から再び海または河川に放水される。復水器３の内部には多数の復水器チューブ７が内蔵されており、循環水はこの復水器チューブ７の内部を通過することにより、復水器３の近傍に設けられた蒸気タービン８からの排気蒸気と熱交換を行い、蒸気タービン８からの排気蒸気を凝縮させる。これにより復水器３を通過した後の循環水の温度は、復水器３の入口側、すなわち、もともとの海水または河川水の温度に比べ、通常、数度Ｃから十数度Ｃ、温度上昇することになる。この温度上昇した循環水は放水口６から外部の海または河川に排出される。
【０００３】
ここでの現象を蒸気タービンサイクル側の蒸気・給水の状態変化において、熱力学的にみると、図７に示すエントロピー・温度線図上に示すようなサイクル変化となる。ここで、四角形の面積SA-A-F-SFと復水器３を通る循環水の重量流量の積が海水または河川に排出される総熱量に等しい。ある蒸気タービンサイクルが事前に決めた出力を行うとき、一般に復水器３の入口側の冷却水の温度が決まると、復水器３の出口側での循環水の温度上昇は復水器３を通過する循環水の重量流量の値に反比例する事がわかる。換言すれば、いかなる場合でも循環水の温度上昇と循環水の重量流量の積は一定である。
【０００４】
一方、海洋または河川の環境保全の方策としては、まず循環水の温度上昇値をなるべく低減する方法、すなわち海水または河川水に生息する生物に対するサーマルショックを緩和する方策がとられている。このためには上記の説明のように、復水器３を通過する循環水の重量流量の値を増加させ、循環水の温度上昇値を低減することが通常行われる。これは復水器３を大きく設計する事および循環水ポンプ２を大きく設計することで実現される。
【０００５】
また、さらなる環境保全の方策として、海洋または河川に排出される総熱量を低減することが要求されるが、蒸気タービンサイクルの発電出力を事前に決めた値に保持する条件のもとでは、総熱量の全てを海洋または河川に排出していたのではこの要求は決して満たされない。そこで近年図８に示すように、冷却水の循環系統において、復水器３の後の循環水系統にクーリングタワー９を設置して、これにより復水器３から排出される総熱量の一部を大気に排出する方法が採られることがある。このクーリングタワー９を一般にヘルパークーリングタワーと称している。復水器３を出た循環水は、循環水ブースタポンプ１０により再度昇圧され、クーリングタワー９に通水される。循環水はクーリングタワー９で保有する熱量の一部を大気中に排出した後、海洋または河川に放出されることになる。この方法により海洋または河川に排出される総熱量を低減することが可能である。
【０００６】
【発明が解決しようとする課題】
海洋および河川の環境保全のうち、これまでに説明したようにサーマルショック防止の方策として放水口６から排出する循環水の温度上昇を低く抑えるためには復水器３および循環水ポンプ２を大きく設計しなければならない。これは発電プラントの建設費を増加させるばかりでなく、ポンプの運転に要する所内電力を費やすため、発電設備全体の効率を低下させている。
【０００７】
また、海洋または河川に排出する総熱量を低減しようとすれば、クーリングタワー９および循環水ブースターポンプ１０等の設置が必要になり、これらの機器は非常に大きな設備であることから、これらの設置のため発電プラントの建設費を大きく増加させるばかりでなく、発電設備全体の効率をさらに低下させている。
【０００８】
さらに、循環水が海水またはそれに近い性状の塩水である場合、クーリングタワー９から周囲に飛散する循環水により、周囲の設備および環境に塩害を及ぼす。加えてクーリングタワー９の内部に循環水によって運ばれた貝類、バクテリア等の発生、付着による性能劣化が生じやすく、また性能劣化を回復するためにはクーリングタワー９の内部の大がかりな洗浄が必要となる。
【０００９】
本発明の目的は、循環水の排出温度の上昇および海洋または河川への放出総排熱量を極力低く抑え、かつ循環水が海水または海水に近い水である場合にもその塩害を最小限に防止する冷却水の循環システムを得ることにある。
【００１０】
【課題を解決するための手段】
本発明の請求項１に係る冷却水の循環システムは、発電設備に設けられこの発電設備の内部に設けられた蒸気タービンから排出される蒸気を凝縮させる復水器と、この復水器と第一の循環水路により結ばれ復水器に発電設備外部からの冷却水を流入させるための取水口と、この取水口と復水器との間に設けられ冷却水を復水器に供給させる循環水ポンプと、復水器から第二の循環水路を経て通過した冷却水を発電設備外部へ流出させるための放水口と、この放水口の隣接部または取水口の隣接部の自由水面から浸水するように設けられ外部からの圧送手段により供給された大気を冷却水の中に気泡として発生させる冷却手段とを備えたことを特徴とする。
【００１１】
本発明の請求項２に係る冷却水の循環システムは、発電設備に設けられこの発電設備の内部に設けられた蒸気タービンから排出される蒸気を凝縮させる復水器と、この復水器と第一の循環水路により結ばれ復水器に発電設備外部からの冷却水を流入させるための取水口と、この取水口と復水器との間に設けられ冷却水を復水器に供給させる循環水ポンプと、復水器から第二の循環水路を経て通過した冷却水を発電設備外部へ流出させるための放水口と、この放水口と復水器との間に設けられ第二の循環水路を通過する冷却水を分岐するための分岐手段と、この分岐手段から第三の循環水路を経て冷却水を導くためのピットと、このピットの自由水面から浸水するように設けられ外部からの圧送手段により供給された大気を冷却水の中に気泡として発生させる冷却手段とを備えたことを特徴とする。
【００１２】
本発明の請求項３に係る冷却水の循環システムは、請求項１または請求項２において、取水口に流入した冷却水の温度を検出するための取水口温度計と、放水口から流出する冷却水の温度を検出するための放水口温度計と、これら各温度計により得られた温度の値の偏差と予め定められた偏差の上限値とから冷却すべき温度を演算し、この冷却すべき温度を受けて、予め定まる冷却手段から発生させる気泡の量とこの冷却手段により循環水が冷却される温度との関係に基いて、必要により設けられた調整弁に冷却手段に圧送する大気の流量を調整する制御指令を出力する演算手段と、を備えたことを特徴とする。
【００１３】
本発明の請求項４に係る冷却水の循環システムは、請求項１ないし請求項３において、冷却手段として、取水口の隣接部、放水口の隣接部またはピットのうちの少なくともいずれかを流れる冷却水の自由水面に浸水するように設けられた配管ヘッダと、この配管ヘッダに大気を供給する圧送手段と、自由水面に浸水するように設けられ圧送手段により供給された大気を配管ヘッダを介して冷却水の中に気泡として発生させる多孔配管とを備えたことを特徴とする。
【００１４】
本発明の請求項５に係る冷却水の循環システムは、請求項１ないし請求項３において、冷却手段として、取水口の隣接部、放水口の隣接部またはピットのうちの少なくともいずれかの流路に設けられここを流れる冷却水の中に気泡を発生させるための複数の孔部を有する面部と、この面部を流路に対して外側から包囲する空気室と、この空気室に大気を供給する圧送手段とを備えたことを特徴とする。
【００１５】
【発明の実施の形態】
以下、本発明の第一の実施の形態（請求項１対応）を図を参照して説明する。図１、図２は、本発明の一実施の形態に係る冷却水の循環システムの概念図を示すものであり、課題を解決するための手段の項で述べた各機器、構築物等により構成される。特に、ここでの発明に係る冷却水の循環システムでは、取水口１側の隣接部１１または放水口６側の隣接部１２の開水路に流れる循環水の自由水面から浸水するように、すなわち、開水路である隣接部において循環水の自由水面よりも低い箇所に、循環水の中に大気を気泡として発生させる冷却手段１３を設ける。この冷却手段１３には、外部から大気を強制的に導くための圧送手段１４が接続されており、必要に応じて冷却手段１３と圧送手段１４との間に冷却手段１３へ導く大気の流量を調整するための調整弁１５が設けられる。
【００１６】
なお、図１は、冷却手段１３を放水口６の隣接部１２に設けたことを示すものであり、他方、図２は冷却手段１３を取水口１の隣接部１１に設けたことを示している。
【００１７】
次に、以上のように構成された本発明の第一の実施の形態の作用について述べる。発電設備の冷却水としての循環水は、海または河川に設けられた取水口１から自由水面を有する隣接部１１を経て循環水ポンプ２にて昇圧され、復水器３の入口側の第一の循環水路４を通り、復水器３に流入する。復水器３の内部には多数の復水器チューブ７が内蔵されており、循環水はこの復水器チューブ７の内部を通過することにより、復水器３の近傍に設けられた蒸気タービン８からの排気蒸気と熱交換を行い、蒸気タービン８からの排気蒸気を凝縮させる。復水器４を出た循環水は、復水器出口側の第二の循環水路５を通り、放水口６の隣接部１２を経て放出口６まで導かれ、発電設備の外に放出される。
【００１８】
本発明の実施の形態に係る冷却水の循環システムでは特に、▲１▼冷却手段１３を放水口６の隣接部１２に設け、あるいは、▲２▼冷却手段１３を取水口１の隣接部１１に設けている。このため、▲１▼にあっては、復水器３の内部の復水器チューブ７を通過し、蒸気タービン８からの排気蒸気と熱交換をすることにより温められた循環水が放水口６から発電設備の外部へ排出される際に、自由水面を有する放水口６の隣接部１２に導かれることになる。この隣接部１２には、昇温された循環水に大気を気泡として発生させる冷却手段１３が設けられている。これにより昇温された循環水は、冷却手段１３から発生した気泡に蒸発することになる。このとき、循環水は気相部である気泡により蒸発熱が奪われ飽和し、この奪われる蒸発熱に応じて循環水の温度が低下する。そして、奪われた蒸発熱は気泡とともに隣接部１２の循環水から浮上し、自由表面から大気に放出される。以上の過程から、昇温された循環水が隣接部１２を通過する際は、冷却手段１３から発生される気泡の作用により冷却され、この冷却された循環水が放水口６に至り、発電設備の外に放出される。
【００１９】
一方、▲２▼にあっては、取水口１から導かれた循環水は、取水口１の自由水面を有する隣接部１１に設けられ大気を気泡として発生させる冷却手段１３によって▲１▼で述べた気泡の作用で冷却された後、循環水ポンプ２により昇圧され、第一の循環水路４を経て復水器３内部の復水器チューブ７に導かれる。こうして、冷却手段１３から発生された気泡の作用によって冷却された循環水が復水器３に導かれた場合、復水器チューブ７の内部を流れる冷却された循環水と復水器チューブ７の雰囲気である蒸気タービン８から排出された排気蒸気との温度勾配が大きくとれるので復水器３の真空度が増し、発電設備の出力の上昇が図れる。また、冷却手段１３から発生した気泡の作用によって予め冷却された循環水が復水器３の復水器チューブ７に供給されるので、冷却手段１３を設けなかった場合に比べて、放水口６から発電設備の外に放出される循環水の温度を低減することができる。
【００２０】
以下、本発明の第二の実施の形態（請求項２対応）を図を参照して説明する。図３は、本発明の一実施の形態に係る冷却水の循環システムの概念図を示すものであり、課題を解決するための手段の項で述べた各機器、構築物等により構成される。特に、ここでの発明に係る冷却水の循環システムでは、先の実施の形態のように開水路である図１中の隣接部１２を設ける十分な領域を確保することが困難な発電設備を想定しており、復水器３と放水口６とを結ぶ第二の循環水路５の中途部において復水器３からの循環水を分岐させるための分岐手段１６と、この分岐手段１６から分岐された復水器３からの循環水を第三の循環水路１７を経て流入させるピット１８と、このピット１８に流入した循環水の自由水面から浸水するように、すなわち、ピット１８において循環水の自由水面よりも低い箇所に、循環水の中に大気を気泡として発生させる冷却手段１３を設ける。この冷却手段１３には、外部から大気を強制的に導くための圧送手段１４が接続されており、必要に応じて冷却手段１３と圧送手段１４との間に冷却手段１３へ導く大気の流量を調整するための調整弁１５が設けられる。図３においては、ピット１８から流出する循環水は、必要に応じて設けられる第四の循環水路１９を経て、分岐手段１６よりも下流側の第二の循環水路と合流し、放水口６に至り、ここから発電設備の外に放出される。（図３に示すケースの他に、循環水を第四の循環水路１９を第二の循環水路に合流させずに、ピット１８から直接放水口６に導くことも考えられる。）
なお、先の実施の形態と同様、冷却手段１３には、外部から大気を強制的に導くための圧送手段１４が接続されており、必要に応じて冷却手段１３と圧送手段１４との間に冷却手段１３へ導く大気の流量を調整するための調整弁１５が設けられる。
【００２１】
次に、以上のように構成された本発明の第二の実施の形態の作用について述べる。発電設備の冷却水としての循環水は、海または河川に設けられた取水口１から自由水面を有する隣接部１１を経て循環水ポンプ２にて昇圧され、復水器３の入口側の第一の循環水路４を通り、復水器３に流入する。復水器３の内部には多数の復水器チューブ７が内蔵されており、循環水はこの復水器チューブ７の内部を通過することにより、復水器３の近傍に設けられた蒸気タービン８からの排気蒸気と熱交換を行い、蒸気タービン８からの排気蒸気を凝縮させる。復水器４を出た循環水は、復水器３出口側の第二の循環水路５を通り、放水口６の隣接部１２を経て放出口６まで導かれ、発電設備の外に放出される。
【００２２】
本発明の実施の形態に係る冷却水の循環システムにより構成したピット１８を設けることにより、先の実施の形態で得られる冷却手段１３の気泡の作用を、特に、ピット１８において利用している。このピット１８の循環水に浸水するように設けた冷却手段１３、第三の循環水路１７および分岐手段１６を設けることにより、先の実施の形態のように図１中の開水路である隣接部１２を設ける十分な領域を確保することが困難な発電設備であっても、ピット１８における冷却手段１３から発生される気泡の作用を得ることが可能となり、放水口６等から発電設備の外に放出される循環水の温度を低減することができる。
【００２３】
以下、本発明の第三の実施の形態（請求項３対応）を図を参照して説明する。図４は、本発明の一実施の形態に係る冷却水の循環システムの概念図を示すものであり、課題を解決するための手段の項で述べた各機器、構築物等により構成される。特に、ここでの発明に係る冷却水の循環システムは、冷却手段１３から循環水の中に気泡を発生させる量を、すなわち、復水器３によって昇温された循環水を、これまでに述べた気泡の作用により冷却して発電設備の外に放出する際に要する冷却の程度を調整する機器を備えている。
【００２４】
次に、以上のように構成された本発明の第三の実施の形態の作用について述べる。発電設備の冷却水としての循環水は、海または河川に設けられた取水口１から自由水面を有する隣接部１１を経て循環水ポンプ２にて昇圧され、復水器３の入口側の第一の循環水路４を通り、復水器３に流入することになるが、取水口１から循環水が流入する際に取水口温度計２０によって取水口１から発電設備内に取入れられる循環水の温度を検出できる。ここで温度を検出された循環水は、復水器３の内部に多数配された復水器チューブ７を通り、この復水器チューブ７の内部を通過することにより、復水器３の近傍に設けられた蒸気タービン８からの排気蒸気と熱交換を行い、蒸気タービン８からの排気蒸気を凝縮させる。ここで熱交換を行って昇温された循環水は、第二の循環水路を流れる際に、後述する演算を行うケースにあっては、流量計２１によりその流量が検出される。そして、ここで流量が検出された循環水は放水口６の隣接部１２に流れ、この隣接部１２に設けられた冷却手段１３から発生された気泡によって上述の気泡の作用により冷却された後、放水口６から発電設備の外に放出される。この際に循環水は、放水口温度計２２によってその温度が検出される。
【００２５】
ところで、上述の取水口温度計２０により得られた検出値と流量計２１により得られた検出値との温度差（偏差）には、発明が解決しようとする課題の項でも述べたように、サーマルショックを防止する観点からの制約がある。このため、循環水が、復水器３で熱交換によって昇温されることにより予め定められた温度の偏差の上限値を超えた場合は、その超えた分を冷却すべき温度と認識し、冷却手段１３から発生させる気泡の作用により冷却する必要がある。その超えた分を冷却するために本発明の実施形態に係る冷却水の循環システムは、第一の演算を行うケースとして、以下に示すステップ（Ｓ）を有する演算器２３を備えており、この演算器２３を備えたことによって、放出口６から放出する循環水の温度を低減させ適切な値に維持できる。
【００２６】
Ｓ１１：取水口温度計２０および放水口温度計２２から検出された各温度の値を入力し偏差（ΔＴ）を演算する
Ｓ１２：Ｓ１１でのΔＴと、予め定められた偏差の上限値とから、これらの差（ΔＴu 「超えた分」）を演算する
Ｓ１３：冷却手段１３から発生させる気泡の量（Ｖ）とここで発生された気泡の作用により循環水を冷却させる温度との関係に基づき、Ｓ１２でのΔＴu を冷却させるために必要な気泡の量（Ｖu ）を演算する
Ｓ１４：圧送手段１４の容量により予め定まる供給可能な大気の量（Ｖ0 ）とＳ１３のＶu との差分を比較し、この差分をゼロにするように、必要により設けられた調整弁１５の開閉を行うための制御指令を調整弁１５に出力する
第二の演算を行うケースとして、以下に示すステップ（Ｓ）を有する演算器２３を備えており、この演算器２３を備えたことによって、第一の演算を行うケースと同様に、放出口６から放出する循環水の温度を低減させ適切な値に維持できる。なお、このケースにあっては、第二の循環水路５の中途部に流量計２１を設け、冷却手段１３により冷却される昇温された循環水の流量を検出する。
【００２７】
Ｓ２１：取水口温度計２０および放水口温度計２２から検出された各温度の値を入力し偏差（ΔＴ）を演算する
Ｓ２２：Ｓ２１でのΔＴと流量計２１により得られる検出値との乗算値と、この乗算値に対応する予め定めた上限値とを比較し、これらの差（ΔＱu 「超えた分」）を演算する
Ｓ２３：冷却手段１３から発生させる気泡の量（Ｖ）とここで発生された気泡の作用により循環水を冷却させる温度との関係に基づき、Ｓ２２でのΔＱu を冷却させるために必要な気泡の量（Ｖu ）を演算する
Ｓ２４：圧送手段１４の容量により予め定まる供給可能な大気の量（Ｖ0 ）とＳ２３のＶu との差分を比較し、この差分をゼロにするように、必要により設けられた調整弁１５の開閉を行うための制御指令を調整弁１５に出力する
これらの一連のステップ（Ｓ）による演算のケースのうち、少なくとも一つ（Ｓ１１〜Ｓ１４またはＳ２１〜Ｓ２４）を行う演算器２３を備えたことにより、放出口６から放出する循環水の温度を適切な値に維持することができる。
【００２８】
以下、本発明の第四の実施の形態（請求項４対応）を図を参照して説明する。図１ないし図４は、本発明の一実施の形態に係る冷却水の循環システムの概念図を示すものであり、課題を解決するための手段の項で述べた各機器、構築物等により構成される。特に、ここでの発明に係る冷却水の循環システムは、循環水の中に気泡を発生させる冷却手段１３の構成を示すものである。
【００２９】
冷却手段１３は、図１においては放水口６の隣接部１２に、図２においては取水口１の隣接部１１に、そして図３においてはピット１８に、それぞれ開水路となる箇所の循環水の自由水面から浸水するように設けられている。なお、図４にあっては、図１に示す放水口６の隣接部１２に設けられ、さらに、先の実施の形態で述べた一連の機器が設けられることにより放水口６から放出する循環水の温度を適正な値に維持する様子を示している。
【００３０】
空気圧縮機あるいはファンにより大気を圧送する圧送手段１４からの空気は、必要により設けられた調整弁１５を経て、冷却手段１３を構成する配管ヘッダ２４に供給される。配管ヘッダ２４には所定数の多孔配管２５が接続されており、配管ヘッダ２４に供給された空気は、無数の孔部を有する多孔配管２５の中を通過することにより、周囲の循環水に、無数の気泡として放出される。なお、多孔配管２５の配管ヘッダ２４に接続しない端は閉じておく。ここで放出された無数の気泡は、上述の気泡の作用を生じさせることになる。この気泡の作用は、気泡のキメが細かければ細かいほど一定空気量に対する気泡の表面積が大きくなることから循環水の気泡への蒸発が促進される。よって、循環水の流速、循環水中の異物による目詰まり等の影響を考慮しつつ、多孔配管２５に設ける孔部を小さくすることが望まれる。
【００３１】
このように構成された冷却水の循環システムにあっては、上述の気泡の作用により、発電設備から放出する循環水の温度を低減できる。
【００３２】
以下、本発明の第五の実施の形態（請求項５対応）を図を参照して説明する。図５は、本発明の一実施の形態に係る冷却水の循環システムの概念図を示すものであり、課題を解決するための手段の項で述べた各機器、構築物等により構成される。特に、ここでの発明に係る冷却水の循環システムは、循環水の中に気泡を発生させる冷却手段１３の構成を示すものである。
【００３３】
空気圧縮機あるいはファンにより大気を圧送する圧送手段１４からの空気は、必要により設けられた調整弁１５を経て、冷却手段１３を構成する空気室２６に供給される。空気室２６は、循環水の開水路となる流路に圧送手段１４からの空気を気泡として発生するように設けた複数の孔部２７を有する面部２８を、流路である隣接部１１あるいは１３もしくはピット１８に対して外側から包囲するように設けられている。なお、面部２８は、流路の底面が望ましいが側面とすることも想定される。
【００３４】
こうして、空気室２６に供給された圧送手段１４からの空気は、空気室２６により包囲された面部２８に設けられた複数の孔部２７から循環水の中に気泡として放出され、上述の気泡の作用を生じさせることになる。この気泡の作用は、気泡のキメが細かければ細かいほど一定空気量に対する気泡の表面積が大きくなることから循環水の気泡への蒸発が促進される。よって、循環水の流速、循環水中の異物による目詰まり等の影響を考慮しつつ、面部２８に設ける孔部２７を小さくすることが望まれる。
【００３５】
このように構成された冷却水の循環システムにあっては、上述の気泡の作用により、発電設備から放出する循環水の温度を低減できる。
【００３６】
【発明の効果】
以上述べたように本発明によれば、冷却手段１３から循環水の中へ発生される気泡の作用により、発電設備から海洋あるいは河川へ放出する循環水の温度を冷却することができるため、循環水の排出温度の上昇および海洋あるいは河川への放出総排熱量を極力低く抑えることをクーリングタワー等の建設なしに実現でき、かつ循環水が海水または海水に近い水である場合にもその塩害を最小限に防止することができる。
【図面の簡単な説明】
【図１】本発明の一実施の形態に係る冷却水の循環システムの概念図。
【図２】本発明の一実施の形態に係る冷却水の循環システムの概念図。
【図３】本発明の一実施の形態に係る冷却水の循環システムの概念図。
【図４】本発明の一実施の形態に係る冷却水の循環システムの概念図。
【図５】本発明の一実施の形態に係る冷却水の循環システムの概念図。
【図６】従来の冷却水の循環システムの概念図。
【図７】蒸気タービンサイクル側の蒸気・給水の状態変化を示したエントロピー・温度線図。
【図８】従来の冷却水の循環システムの概念図。
【符号の説明】
１…取水口、２…循環水ポンプ、３…復水器、４…第一の循環水路、５…第二の循環水路、６…放水口、７…復水器チューブ、８…蒸気タービン、９…クーリングタワー、１０…循環水ブースタポンプ、１１…隣接部、１２…隣接部、１３…冷却手段、１４…圧送手段、１５…調整弁、１６…分岐手段、１７…第三の循環水路、１８…ピット、１９…第四の循環水路、２０…取水口温度計、２１…流量計、２２…放水口温度計、２３…演算器、２４…配管ヘッダ、２５…多孔配管、２６…空気室、２７…孔部、２８…面部。[0001]
BACKGROUND OF THE INVENTION
In a power plant having a steam turbine condenser such as a thermal power plant, a nuclear power plant, or a combined cycle power plant, the present invention supplies cooling water boosted by a circulating water pump to the condenser. The present invention relates to a cooling water circulation system for cooling a condenser in which heat is exchanged by condensing exhaust steam from a steam turbine and the temperature rises.
[0002]
[Prior art]
An example of the cooling water circulation system for cooling the condenser in the power plant is shown in FIG. When seawater or river water is used as the circulating water used for cooling, the circulating water (cooling water) is supplied to the circulating water pump 2 from the intake port 1 provided in the sea or river. Then, the pressure is increased and the refrigerant enters the condenser 3 through the first circulation water channel 4 on the inlet side of the condenser 3. Then, it leaves the condenser 3, passes through the second circulating water channel 5 on the condenser outlet side, and is discharged again from the outlet 6 into the sea or river. A large number of condenser tubes 7 are built in the condenser 3, and the circulating water passes through the condenser tube 7, whereby a steam turbine provided in the vicinity of the condenser 3. Heat exchange with the exhaust steam from 8 is performed, and the exhaust steam from the steam turbine 8 is condensed. As a result, the temperature of the circulating water after passing through the condenser 3 is usually several degrees C to a few dozen degrees C, compared with the temperature of the inlet side of the condenser 3, that is, the original seawater or river water. Will rise. The circulating water whose temperature has risen is discharged from the outlet 6 to the outside sea or river.
[0003]
When the phenomenon here is seen thermodynamically in the state change of the steam / feed water on the steam turbine cycle side, the cycle change is as shown on the entropy / temperature diagram shown in FIG. Here, the product of the square area SA-AF-SF and the weight flow rate of circulating water passing through the condenser 3 is equal to the total amount of heat discharged to seawater or rivers. When a certain steam turbine cycle performs a predetermined output, generally, when the temperature of the cooling water on the inlet side of the condenser 3 is determined, the temperature rise of the circulating water on the outlet side of the condenser 3 is increased. It can be seen that it is inversely proportional to the value of the weight flow rate of the circulating water passing through. In other words, in any case, the product of the temperature rise of the circulating water and the weight flow rate of the circulating water is constant.
[0004]
On the other hand, as a measure for protecting the environment of the ocean or river, first, a method of reducing the temperature rise value of the circulating water as much as possible, that is, a measure of mitigating thermal shock to organisms inhabiting seawater or river water is taken. For this purpose, as described above, it is usual to increase the value of the weight flow rate of the circulating water passing through the condenser 3 and reduce the temperature rise value of the circulating water. This is realized by designing the condenser 3 large and designing the circulating water pump 2 large.
[0005]
Further, as a further environmental conservation measure, it is required to reduce the total amount of heat discharged to the ocean or river, but under conditions that maintain the power generation output of the steam turbine cycle at a predetermined value, This requirement is never met when all of the heat is discharged into the ocean or river. Therefore, in recent years, as shown in FIG. 8, in the cooling water circulation system, a cooling tower 9 is installed in the circulation water system after the condenser 3, so that a part of the total amount of heat discharged from the condenser 3 is reduced. A method of discharging to the atmosphere may be used. This cooling tower 9 is generally called a helper cooling tower. The circulating water exiting the condenser 3 is boosted again by the circulating water booster pump 10 and is passed through the cooling tower 9. Circulating water is discharged into the ocean or river after a part of the amount of heat held in the cooling tower 9 is discharged into the atmosphere. This method can reduce the total amount of heat discharged to the ocean or river.
[0006]
[Problems to be solved by the invention]
In order to keep the temperature rise of circulating water discharged from the outlet 6 as a measure for preventing thermal shock, as described above, the condenser 3 and the circulating water pump 2 are made large. Must design. This not only increases the construction cost of the power plant, but also consumes the on-site power required to operate the pump, thus reducing the efficiency of the entire power generation facility.
[0007]
Further, if it is intended to reduce the total amount of heat discharged to the ocean or river, it is necessary to install a cooling tower 9 and a circulating water booster pump 10, etc., and these devices are very large facilities. Therefore, not only the construction cost of the power plant is greatly increased, but also the efficiency of the entire power generation facility is further reduced.
[0008]
Further, when the circulating water is sea water or salt water having a property close to it, the circulating water scattered around from the cooling tower 9 causes salt damage to surrounding facilities and the environment. In addition, performance degradation due to generation and adhesion of shellfish, bacteria, etc. carried by circulating water inside the cooling tower 9 is likely to occur, and extensive cleaning of the interior of the cooling tower 9 is required to recover performance degradation.
[0009]
The object of the present invention is to minimize the rise in circulating water discharge temperature and the total amount of heat discharged to the ocean or river as much as possible, and to prevent salt damage even when the circulating water is seawater or water close to seawater. The purpose is to obtain a cooling water circulation system.
[0010]
[Means for Solving the Problems]
A cooling water circulation system according to claim 1 of the present invention includes a condenser that is provided in a power generation facility and that condenses steam discharged from a steam turbine provided in the power generation facility. A water intake connected by a single circulation channel to allow cooling water from the outside of the power generation facility to flow into the condenser, and a circulation provided between the intake and the condenser to supply the cooling water to the condenser Water is submerged from the water pump, a water outlet for discharging cooling water that has passed through the second circulation channel from the condenser to the outside of the power generation facility, and a free water surface adjacent to this water outlet or adjacent to the water intake. And a cooling means for generating the air supplied by the external pressure feeding means as bubbles in the cooling water.
[0011]
A cooling water circulation system according to a second aspect of the present invention includes a condenser that is provided in a power generation facility and that condenses steam discharged from a steam turbine provided in the power generation facility, A water intake connected by a single circulation channel to allow cooling water from the outside of the power generation facility to flow into the condenser, and a circulation provided between the intake and the condenser to supply the cooling water to the condenser A water pump, a water outlet for allowing cooling water that has passed through the second circulation channel from the condenser to flow outside the power generation facility, and a second circulation channel provided between the water outlet and the condenser A branching means for branching the cooling water passing through the pit, a pit for guiding the cooling water from the branching means through the third circulation channel, and a pressure feed from the outside provided to be submerged from the free water surface of the pit The air supplied by the means and bubbles in the cooling water Characterized in that a cooling means for generating Te.
[0012]
The cooling water circulation system according to a third aspect of the present invention is the cooling water circulation system according to the first or second aspect, wherein the temperature of the cooling water flowing into the water intake port is detected and the cooling water flowing out from the water discharge port. Calculate the temperature to be cooled from the water outlet thermometer for detecting the temperature of the water, the deviation of the temperature value obtained by each of these thermometers and the upper limit value of the predetermined deviation, and this cooling should be done Based on the relationship between the amount of bubbles generated from the predetermined cooling means in response to the temperature and the temperature at which the circulating water is cooled by this cooling means, the flow rate of the air pressure-fed to the cooling means to the regulating valve provided if necessary And a calculation means for outputting a control command for adjusting.
[0013]
A cooling water circulation system according to a fourth aspect of the present invention is the cooling system according to any one of the first to third aspects, wherein the cooling water flows through at least one of the adjacent portion of the water intake, the adjacent portion of the water discharge port, or the pit as the cooling means. A pipe header provided to immerse the water in the free water surface, a pressure feeding means for supplying air to the pipe header, and an air supplied by the pressure feeding means provided to immerse in the free water surface through the pipe header. And a porous pipe that is generated as bubbles in the cooling water.
[0014]
A cooling water circulation system according to a fifth aspect of the present invention is the cooling water circulation system according to the first to third aspects of the present invention, wherein the cooling means is a flow path of at least one of the adjacent part of the water intake, the adjacent part of the water outlet, or the pit A surface portion having a plurality of holes for generating bubbles in the cooling water flowing therethrough, an air chamber surrounding the surface portion from the outside with respect to the flow path, and supplying air to the air chamber And a pressure feeding means.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention (corresponding to claim 1) will be described with reference to the drawings. FIG. 1 and FIG. 2 are conceptual diagrams of a cooling water circulation system according to an embodiment of the present invention, and are configured by each device, structure, and the like described in the section of means for solving the problems. The In particular, in the cooling water circulation system according to the present invention, so as to be submerged from the free water surface of the circulating water flowing in the open channel of the adjacent portion 11 on the intake port 1 side or the adjacent portion 12 on the water discharge port 6 side, that is, Cooling means 13 for generating air as bubbles in the circulating water is provided at a location lower than the free water surface of the circulating water in the adjacent portion which is an open channel. The cooling means 13 is connected to a pressure feeding means 14 for forcibly guiding the atmosphere from the outside, and the flow rate of the atmosphere guided to the cooling means 13 is set between the cooling means 13 and the pressure feeding means 14 as necessary. An adjustment valve 15 for adjustment is provided.
[0016]
FIG. 1 shows that the cooling means 13 is provided in the adjacent portion 12 of the water outlet 6, while FIG. 2 shows that the cooling means 13 is provided in the adjacent portion 11 of the water outlet 1. Yes.
[0017]
Next, the operation of the first embodiment of the present invention configured as described above will be described. Circulating water as cooling water for the power generation facility is boosted by the circulating water pump 2 from the intake port 1 provided in the sea or river through the adjacent portion 11 having a free water surface, and is first on the inlet side of the condenser 3. Through the circulation channel 4 and into the condenser 3. A large number of condenser tubes 7 are built in the condenser 3, and the circulating water passes through the condenser tube 7, whereby a steam turbine provided in the vicinity of the condenser 3. Heat exchange with the exhaust steam from 8 is performed, and the exhaust steam from the steam turbine 8 is condensed. The circulating water exiting the condenser 4 passes through the second circulating water channel 5 on the condenser outlet side, is led to the discharge port 6 through the adjacent portion 12 of the discharge port 6, and is discharged outside the power generation facility. .
[0018]
Particularly in the cooling water circulation system according to the embodiment of the present invention, (1) the cooling means 13 is provided in the adjacent portion 12 of the water outlet 6 or (2) the cooling means 13 is provided in the adjacent portion 11 of the water outlet 1. Provided. For this reason, in (1), circulating water heated by exchanging heat with the exhaust steam from the steam turbine 8 through the condenser tube 7 inside the condenser 3 is discharged into the outlet 6. Is discharged from the power generation facility to the adjacent portion 12 of the water discharge port 6 having a free water surface. The adjacent portion 12 is provided with a cooling means 13 for generating air as bubbles in the heated circulating water. Thus, the circulating water whose temperature has been increased evaporates into bubbles generated from the cooling means 13. At this time, the circulating water is saturated by evaporating the evaporation heat by the bubbles that are the gas phase, and the temperature of the circulating water is lowered according to the evaporation heat. Then, the deprived heat of evaporation rises from the circulating water in the adjacent portion 12 together with the bubbles, and is released from the free surface to the atmosphere. From the above process, when the heated circulating water passes through the adjacent portion 12, it is cooled by the action of bubbles generated from the cooling means 13, and this cooled circulating water reaches the water discharge port 6 to generate power generation equipment. Released out of the water.
[0019]
On the other hand, in (2), the circulating water introduced from the intake 1 is described in (1) by the cooling means 13 provided in the adjacent portion 11 having the free water surface of the intake 1 to generate air as bubbles. After being cooled by the action of the air bubbles, the pressure is raised by the circulating water pump 2 and led to the condenser tube 7 inside the condenser 3 through the first circulating water channel 4. Thus, when the circulating water cooled by the action of the bubbles generated from the cooling means 13 is led to the condenser 3, the cooled circulating water flowing inside the condenser tube 7 and the condenser tube 7 Since the temperature gradient with the exhaust steam discharged from the steam turbine 8 which is the atmosphere is large, the vacuum degree of the condenser 3 is increased, and the output of the power generation equipment can be increased. Further, since the circulating water cooled in advance by the action of the bubbles generated from the cooling means 13 is supplied to the condenser tube 7 of the condenser 3, compared with the case where the cooling means 13 is not provided, the water outlet 6. Therefore, the temperature of the circulating water discharged from the power generation facility can be reduced.
[0020]
Hereinafter, a second embodiment (corresponding to claim 2) of the present invention will be described with reference to the drawings. FIG. 3 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention, and includes the devices, structures, and the like described in the section for solving the problems. In particular, the cooling water circulation system according to the present invention assumes a power generation facility in which it is difficult to ensure a sufficient region for providing the adjacent portion 12 in FIG. 1 that is an open channel as in the previous embodiment. The branching means 16 for branching the circulating water from the condenser 3 in the middle of the second circulating water channel 5 connecting the condenser 3 and the outlet 6 is branched from the branching means 16. The pit 18 into which the circulating water from the condenser 3 flows in via the third circulation channel 17 and the free water surface of the circulating water that has flowed into the pit 18 are immersed, that is, the free water in the pit 18 is free. Cooling means 13 for generating air as bubbles in the circulating water is provided at a location lower than the water surface. The cooling means 13 is connected to a pressure feeding means 14 for forcibly guiding the atmosphere from the outside, and the flow rate of the atmosphere guided to the cooling means 13 is set between the cooling means 13 and the pressure feeding means 14 as necessary. An adjustment valve 15 for adjustment is provided. In FIG. 3, the circulating water flowing out from the pit 18 passes through a fourth circulating water channel 19 provided as necessary, and merges with the second circulating water channel downstream from the branching means 16, and enters the water outlet 6. It is discharged from the power generation facility from here. (In addition to the case shown in FIG. 3, it is also conceivable that the circulating water is directly led from the pit 18 to the water outlet 6 without joining the fourth circulating water channel 19 to the second circulating water channel.)
As in the previous embodiment, the cooling means 13 is connected to the pressure feeding means 14 for forcibly guiding the atmosphere from the outside, and between the cooling means 13 and the pressure feeding means 14 as necessary. An adjustment valve 15 is provided for adjusting the flow rate of the air led to the cooling means 13.
[0021]
Next, the operation of the second embodiment of the present invention configured as described above will be described. Circulating water as cooling water for the power generation facility is boosted by the circulating water pump 2 from the intake port 1 provided in the sea or river through the adjacent portion 11 having a free water surface, and is first on the inlet side of the condenser 3. Through the circulation channel 4 and into the condenser 3. A large number of condenser tubes 7 are built in the condenser 3, and the circulating water passes through the condenser tube 7, whereby a steam turbine provided in the vicinity of the condenser 3. Heat exchange with the exhaust steam from 8 is performed, and the exhaust steam from the steam turbine 8 is condensed. The circulating water exiting the condenser 4 passes through the second circulating water channel 5 on the outlet side of the condenser 3, is led to the discharge port 6 through the adjacent portion 12 of the water discharge port 6, and is discharged outside the power generation facility. The
[0022]
By providing the pit 18 constituted by the cooling water circulation system according to the embodiment of the present invention, the action of the bubbles of the cooling means 13 obtained in the previous embodiment is utilized particularly in the pit 18. By providing the cooling means 13, the third circulating water passage 17 and the branching means 16 provided so as to be immersed in the circulating water of the pit 18, an adjacent portion which is an open water passage in FIG. 1 as in the previous embodiment. Even in a power generation facility for which it is difficult to secure a sufficient area for providing 12, it becomes possible to obtain the action of bubbles generated from the cooling means 13 in the pit 18, and the outside of the power generation facility through the water outlet 6 or the like. The temperature of the circulating water discharged can be reduced.
[0023]
Hereinafter, a third embodiment of the present invention (corresponding to claim 3) will be described with reference to the drawings. FIG. 4 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention, and is configured by each device, structure, and the like described in the section for solving the problem. In particular, the cooling water circulation system according to the present invention has so far described the amount of bubbles generated from the cooling means 13 in the circulating water, that is, the circulating water heated by the condenser 3 so far. It is equipped with a device that adjusts the degree of cooling required when it is cooled by the action of air bubbles and discharged outside the power generation facility.
[0024]
Next, the operation of the third embodiment of the present invention configured as described above will be described. Circulating water as cooling water for the power generation facility is boosted by the circulating water pump 2 from the intake port 1 provided in the sea or river through the adjacent portion 11 having a free water surface, and is first on the inlet side of the condenser 3. The temperature of the circulating water taken into the power generation facility from the intake port 1 by the intake port thermometer 20 when the circulating water flows from the intake port 1 through the circulating water channel 4. Can be detected. The circulating water whose temperature is detected here passes through the condenser tubes 7 arranged in the condenser 3, and passes through the condenser tubes 7, thereby the vicinity of the condenser 3. Heat exchange is performed with the exhaust steam from the steam turbine 8 provided in the steam turbine 8 to condense the exhaust steam from the steam turbine 8. Here, the flow rate of the circulating water heated by the heat exchange is detected by the flow meter 21 in the case where the calculation described later is performed when flowing through the second circulating water channel. And the circulating water by which the flow volume was detected here flows into the adjacent part 12 of the water discharge port 6, and after being cooled by the effect | action of the above-mentioned bubble by the bubble generated from the cooling means 13 provided in this adjacent part 12, It is discharged from the water outlet 6 to the outside of the power generation facility. At this time, the temperature of the circulating water is detected by the outlet thermometer 22.
[0025]
By the way, in the temperature difference (deviation) between the detection value obtained by the water inlet thermometer 20 and the detection value obtained by the flow meter 21, as described in the section of the problem to be solved by the invention, There are restrictions from the viewpoint of preventing thermal shock. For this reason, when circulating water exceeds the upper limit value of the predetermined temperature deviation by raising the temperature by heat exchange in the condenser 3, the excess is recognized as the temperature to be cooled, It is necessary to cool by the action of bubbles generated from the cooling means 13. In order to cool the excess, the cooling water circulation system according to the embodiment of the present invention includes a calculator 23 having the following step (S) as a case of performing the first calculation. By providing the calculator 23, the temperature of the circulating water discharged from the discharge port 6 can be reduced and maintained at an appropriate value.
[0026]
S11: The temperature values detected from the intake port thermometer 20 and the discharge port thermometer 22 are input, and the deviation (ΔT) is calculated.
S12: The difference (ΔTu “exceeded amount”) is calculated from ΔT in S11 and the upper limit value of the predetermined deviation.
S13: The amount of bubbles necessary for cooling ΔTu in S12 based on the relationship between the amount (V) of bubbles generated from the cooling means 13 and the temperature at which the circulating water is cooled by the action of the bubbles generated here. Calculate (Vu)
S14: Comparing the difference between the amount of air that can be supplied (V0) determined in advance by the capacity of the pumping means 14 and Vu in S13, and opening and closing the regulating valve 15 provided as necessary so as to make this difference zero. A control command to perform is output to the adjustment valve 15
As a case where the second calculation is performed, a calculation unit 23 having the following step (S) is provided. By providing this calculation unit 23, the discharge port 6 is provided in the same manner as the case where the first calculation is performed. The temperature of circulating water discharged from the water can be reduced and maintained at an appropriate value. In this case, a flow meter 21 is provided in the middle of the second circulating water channel 5 to detect the flow rate of the heated circulating water cooled by the cooling means 13.
[0027]
S21: Input values of temperatures detected from the intake port thermometer 20 and the discharge port thermometer 22 and calculate a deviation (ΔT).
S22: The multiplication value of ΔT in S21 and the detection value obtained by the flow meter 21 is compared with a predetermined upper limit value corresponding to this multiplication value, and the difference (ΔQu “exceeded amount”) is calculated. Do
S23: The amount of bubbles necessary for cooling ΔQu in S22 based on the relationship between the amount of bubbles (V) generated from the cooling means 13 and the temperature at which the circulating water is cooled by the action of the bubbles generated here. Calculate (Vu)
S24: Comparing the difference between the amount of air that can be supplied (V0) determined in advance by the capacity of the pumping means 14 and Vu in S23, and opening and closing the regulating valve 15 provided as necessary so as to make this difference zero. A control command to perform is output to the adjustment valve 15
By providing the computing unit 23 that performs at least one (S11 to S14 or S21 to S24) of the computation cases in the series of steps (S), the temperature of the circulating water discharged from the discharge port 6 is appropriately set. Value can be maintained.
[0028]
Hereinafter, a fourth embodiment (corresponding to claim 4) of the present invention will be described with reference to the drawings. FIG. 1 to FIG. 4 are conceptual diagrams of a cooling water circulation system according to an embodiment of the present invention, and each of the devices and structures described in the section for solving the problem are configured. The In particular, the cooling water circulation system according to the present invention shows the configuration of the cooling means 13 for generating bubbles in the circulating water.
[0029]
The cooling means 13 is connected to the adjacent portion 12 of the water outlet 6 in FIG. 1, to the adjacent portion 11 of the water intake 1 in FIG. 2, and to the pit 18 in FIG. It is provided to be submerged from the free water surface. In FIG. 4, circulating water that is provided at the adjacent portion 12 of the water discharge port 6 shown in FIG. 1 and that is discharged from the water discharge port 6 by providing the series of devices described in the previous embodiment. This shows how to maintain the temperature at an appropriate value.
[0030]
Air from the pressure feeding means 14 that feeds the atmosphere by an air compressor or a fan is supplied to a pipe header 24 constituting the cooling means 13 through a regulating valve 15 provided as necessary. A predetermined number of perforated pipes 25 are connected to the pipe header 24, and the air supplied to the pipe header 24 passes through the perforated pipe 25 having innumerable hole portions to the surrounding circulating water, Released as countless bubbles. The end of the porous pipe 25 that is not connected to the pipe header 24 is closed. The innumerable bubbles released here cause the above-described bubble action. The bubble effect is such that the finer the texture of the bubble, the greater the surface area of the bubble with respect to a certain amount of air. Therefore, it is desirable to reduce the hole provided in the porous pipe 25 while taking into consideration the influence of the flow rate of the circulating water, clogging due to foreign matter in the circulating water, and the like.
[0031]
In the cooling water circulation system configured as described above, the temperature of the circulating water discharged from the power generation facility can be reduced by the action of the bubbles.
[0032]
Hereinafter, a fifth embodiment (corresponding to claim 5) of the present invention will be described with reference to the drawings. FIG. 5 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention, and is configured by each device, structure, and the like described in the section for solving the problem. In particular, the cooling water circulation system according to the present invention shows the configuration of the cooling means 13 for generating bubbles in the circulating water.
[0033]
Air from the pressure feeding means 14 that feeds the atmosphere by an air compressor or a fan is supplied to an air chamber 26 constituting the cooling means 13 through a regulating valve 15 provided as necessary. The air chamber 26 includes a surface portion 28 having a plurality of hole portions 27 provided so as to generate air from the pressure feeding means 14 as bubbles in a flow path serving as an open channel for circulating water. Alternatively, it is provided so as to surround the pit 18 from the outside. In addition, although the surface part 28 has the desirable bottom face of a flow path, it is also assumed that it is a side surface.
[0034]
In this way, the air from the pressure feeding means 14 supplied to the air chamber 26 is discharged as bubbles into the circulating water from the plurality of holes 27 provided in the surface portion 28 surrounded by the air chamber 26, and It will cause an effect. The bubble effect is such that the finer the texture of the bubble, the greater the surface area of the bubble with respect to a certain amount of air. Therefore, it is desirable to reduce the hole 27 provided in the surface portion 28 in consideration of the influence of the flow rate of the circulating water, clogging due to foreign matter in the circulating water, and the like.
[0035]
In the cooling water circulation system configured as described above, the temperature of the circulating water discharged from the power generation facility can be reduced by the action of the bubbles.
[0036]
【The invention's effect】
As described above, according to the present invention, the temperature of the circulating water discharged from the power generation facility to the ocean or river can be cooled by the action of bubbles generated from the cooling means 13 into the circulating water. The rise of water discharge temperature and the total amount of heat released to the ocean or river can be kept as low as possible without the construction of a cooling tower, etc., and the salt damage is minimized even when the circulating water is seawater or water close to seawater. Can be prevented as much as possible.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention.
FIG. 2 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention.
FIG. 3 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention.
FIG. 4 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention.
FIG. 5 is a conceptual diagram of a cooling water circulation system according to an embodiment of the present invention.
FIG. 6 is a conceptual diagram of a conventional cooling water circulation system.
FIG. 7 is an entropy / temperature diagram showing changes in the state of steam / feed water on the steam turbine cycle side.
FIG. 8 is a conceptual diagram of a conventional cooling water circulation system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Water intake port, 2 ... Circulating water pump, 3 ... Condenser, 4 ... 1st circulating water channel, 5 ... 2nd circulating water channel, 6 ... Outlet, 7 ... Condenser tube, 8 ... Steam turbine, DESCRIPTION OF SYMBOLS 9 ... Cooling tower, 10 ... Circulating water booster pump, 11 ... Adjacent part, 12 ... Adjacent part, 13 ... Cooling means, 14 ... Pressure feeding means, 15 ... Regulating valve, 16 ... Branch means, 17 ... Third circulating water channel, 18 Pit, 19th fourth circulation channel, 20 ... intake port thermometer, 21 ... flow meter, 22 ... outlet thermometer, 23 ... calculator, 24 ... pipe header, 25 ... perforated pipe, 26 ... air chamber, 27 ... hole part, 28 ... surface part.

Claims

A condenser that is provided in the power generation facility and that condenses the steam discharged from the steam turbine provided in the power generation facility, and is connected to the condenser by a first circulation channel, and the power generation facility is connected to the condenser. A water intake for allowing cooling water from the outside to flow in, a circulating water pump provided between the water intake and the condenser, and supplying the cooling water to the condenser; A water outlet for flowing cooling water that has passed through the second circulating water channel to the outside of the power generation facility, and a water supply unit provided to be submerged from a free water surface adjacent to the water outlet or the water intake; A cooling water circulation system comprising cooling means for generating supplied air as bubbles in the cooling water.

A condenser that is provided in the power generation facility and that condenses the steam discharged from the steam turbine provided in the power generation facility, and is connected to the condenser by a first circulation channel, and the power generation facility is connected to the condenser. A water intake for allowing cooling water from the outside to flow in, a circulating water pump provided between the water intake and the condenser, and supplying the cooling water to the condenser; A water outlet for allowing cooling water that has passed through the second circulation channel to flow out of the power generation facility, and cooling water that is provided between the water outlet and the condenser and that passes through the second circulation channel. Branch means for branching, a pit for guiding cooling water from the branch means through a third circulation channel, and an air supplied by external pressure feeding means provided to be submerged from the free water surface of the pit Generated as bubbles in the cooling water Circulation system of the cooling water, characterized in that a cooling means that.

A water inlet thermometer for detecting the temperature of the cooling water flowing into the water inlet, a water outlet thermometer for detecting the temperature of the cooling water flowing out of the water outlet, and obtained by each of these thermometers The temperature to be cooled is calculated from the deviation of the temperature value and the upper limit value of the predetermined deviation, the temperature to be cooled is received, and the amount of bubbles generated from the cooling means determined in advance is circulated by this cooling means. Computation means for outputting a control command for adjusting the flow rate of the atmosphere pressure-fed to the cooling means to a regulating valve provided as necessary based on the relationship with the temperature at which water is cooled, The cooling water circulation system according to claim 1 or 2.

The cooling means includes a pipe header provided so as to be immersed in the free water surface of cooling water flowing through at least one of the adjacent part of the intake port, the adjacent part of the water discharge port, or the pit, and the pipe header. And a perforated pipe for generating air in the cooling water via the pipe header provided so as to be immersed in the free water surface. The cooling water circulation system according to claim 1, wherein:

The cooling means is provided in a flow path of at least one of the adjacent portion of the water intake port, the adjacent portion of the water discharge port, or the pit, and a plurality of holes for generating bubbles in the cooling water flowing therethrough 4. The apparatus according to claim 1, further comprising: a surface portion having a portion; an air chamber that surrounds the surface portion from the outside with respect to the flow path; and a pressure feeding unit that supplies air to the air chamber. The cooling water circulation system described.