JP4663926B2

JP4663926B2 - Heat recovery system

Info

Publication number: JP4663926B2
Application number: JP2001242151A
Authority: JP
Inventors: 武浩清水; 卓治佐伯; 達朗荒井; 究鈴木; 健一田之頭; 和也山口; 義孝栢原; 伸岩田; 桂嗣滝本; 忠男菅原; 博司高木; 和博松本
Original assignee: Saibu Gas Co Ltd; Osaka Gas Co Ltd; Tokyo Gas Co Ltd; Noritz Corp; Toho Gas Co Ltd
Current assignee: Saibu Gas Co Ltd; Osaka Gas Co Ltd; Tokyo Gas Co Ltd; Noritz Corp; Toho Gas Co Ltd
Priority date: 2001-08-09
Filing date: 2001-08-09
Publication date: 2011-04-06
Anticipated expiration: 2021-08-09
Also published as: JP2003056911A

Description

【０００１】
【発明の属する技術分野】
本発明は、ガスエンジン等の熱源が発生する熱を回収するとともに、暖房用熱媒を加熱して暖房端末に供給循環させる熱源器を備える熱回収システムに関する。
【０００２】
【従来の技術】
従来、給湯風呂暖房機を熱源器として有するとともに、ガスエンジン等の熱源からの排熱を回収利用するシステムとして、例えば、図２に示されるものがある。
【０００３】
熱源器としての給湯風呂暖房機５₀は、給水、給湯、高温および低温の各暖房端末からの暖房戻り、低温暖房端末および高温暖房端末用の各接続部５₀ａ〜５₀ｅを備えるとともに、図示しないバーナによって給水を加熱する給湯熱交換器７と、図示しないバーナによって暖房用熱媒としての暖房水を加熱する暖房熱交換器８と、暖房水を、暖房用の高温暖房端末あるいは低温暖房端末に送給する暖房ポンプ９と、暖房水を利用して浴槽水を加熱する風呂熱交換器１０と、浴槽水を浴槽６に送給する風呂ポンプ１１と、電磁弁１２，１３とを備えている。
【０００４】
ガスエンジン１等の熱源からの排熱によって加熱された熱媒が循環する排熱回収回路２₀には、循環ポンプ４と、暖房端末からの戻りの暖房水が循環する排熱暖房熱交換器３と、浴槽水が循環する排熱風呂熱交換器１８とが設けられており、ガスエンジン１の排熱を回収して暖房水および浴槽水を加熱するものである。
【０００５】
かかるシステムでは、ガスエンジン１の排熱を利用して風呂の追焚きを行う場合には、給湯風呂暖房機５₀の風呂ポンプ１１を駆動して浴槽６の浴槽水を循環させる一方、ガスエンジン１および循環ポンプ４を駆動してガスエンジン１の排熱によって加熱された熱媒を循環させて排熱風呂熱交換器１８で浴槽水を直接加熱して追焚きを行うものである。
【０００６】
また、ガスエンジン１の排熱を利用することなく、風呂の追焚きを行う場合には、暖房ポンプ９を駆動して暖房水を、暖房熱交換器８で加熱し、電磁弁１３および風呂熱交換器１０を介して暖房ポンプ９へ戻す内循環回路で循環させる一方、給湯風呂暖房機５₀の風呂ポンプ１１を駆動して浴槽水を循環させて風呂熱交換器１０で暖房水によって間接加熱して追焚きを行うものである。
【０００７】
【発明が解決しようとする課題】
このように、風呂の追焚きにガスエンジン１などの熱源の排熱を利用する従来のシステムでは、給湯風呂暖房機５₀の風呂熱交換器１０とは別に、排熱回収回路２₀に、浴槽水を直接加熱するための排熱風呂熱交換器１８を追加する必要があり、コストが高くつくといった難点があった。
【０００８】
本発明は、上述のような点に鑑みて為されたものであって、熱交換器を追加することなく、熱源から回収した熱による風呂の追焚きを可能にすることを主たる目的とする。
【０００９】
【課題を解決するための手段】
本発明では、上述の目的を達成するために、次のように構成している。
【００１０】
すなわち、請求項１に係る本発明の熱回収システムは、熱源の発生する熱を回収して暖房用熱媒を加熱する熱回収回路と、暖房用熱媒を低温暖房循環回路に設けられた低温暖房端末に循環供給するとともに、浴槽水を暖房用熱媒によって間接加熱する熱源器とを備える熱回収システムにおいて、前記低温暖房循環回路の往き経路を分岐して戻り経路に合流させたバイパス経路を設けるとともに、前記戻り経路の前記合流させた位置の下流側であって、前記熱源器の上流側には、暖房用熱媒を加熱する前記熱回収回路の熱交換器を配置している。
【００１１】
請求項１に係る本発明によれば、暖房用熱媒によって浴槽水を間接加熱する際には、低温暖房循環回路に設けたバイパス経路で暖房用熱媒を循環させることにより、熱回収回路の熱交換器によって、熱源からの熱を回収して暖房用熱媒を加熱できることなる。したがって、暖房用熱媒を加熱する熱交換器とは別に熱交換器を追加することなく、熱回収回路で回収した熱を利用して風呂の追焚きを行うことが可能となる。
【００１２】
請求項２に係る本発明は、請求項１の発明において、前記熱源器は、暖房用熱媒を加熱する暖房熱交換器と、風呂から供給循環される浴槽水を前記暖房用熱媒によって加熱する風呂熱交換器と、暖房用熱媒を循環させる暖房ポンプと、該熱源器内部の内循環回路とを備え、前記内循環回路は、前記暖房熱交換器、前記風呂熱交換器および前記暖房ポンプを結ぶとともに、分岐されて前記低温暖房循環回路に接続され、前記熱源の発生する熱を回収して風呂の追焚きを行うときには、前記暖房用熱媒を、前記内循環回路で循環させる一方、前記低温暖房循環回路の前記バイパス経路を介して循環させるものである。
【００１３】
請求項２に係る本発明によれば、暖房用熱媒を、内循環回路から分岐された低温暖房循環回路のバイパス経路を介して循環させて熱源の発生する熱を回収する一方、内循環回路の風呂熱交換器を介して循環させることで、回収した熱によって浴槽水を間接加熱して風呂の追焚きを行うことができる。
【００１４】
請求項３に係る本発明は、請求項２の発明において、前記熱源の発生する熱を回収して風呂の追焚きを行うときに、前記暖房熱交換器による暖房用熱媒の加熱を併せて行うものである。
【００１５】
請求項３に係る本発明によれば、熱源から回収した熱だけでは、風呂の追焚きに不充分であるときには、熱源器の熱交換器で暖房用熱媒を加熱して追焚きを行うことが可能となる。しかも、熱源器の熱交換器で暖房用熱媒を加熱した場合にも、低温暖房循環回路へ供給される暖房用熱媒の温度は、高温暖房の場合に比べて低いので、この暖房用熱媒を熱回収回路の熱交換器で加熱することができ、熱源器の熱交換器および熱回収回路の熱交換器による暖房用熱媒の同時加熱が可能となる。
【００１６】
【発明の実施の形態】
以下、本発明の詳細を図面に示す実施形態に基づいて説明する。
【００１７】
（実施の形態１）
図１は、本発明の一つの実施の形態に係る熱回収システムを適用した給湯風呂暖房システムの概略構成図である。
【００１８】
同図において、１は熱源としての発電機能を有するガスエンジンであり、このガスエンジン１によって発電された電気は、当該給湯風呂暖房システムが設置されている一般家庭の家庭内負荷に供給される。
【００１９】
２はガスエンジン１からの排熱、例えば、ガスエンジンンの水冷およびガスエンジンの排ガスによって加熱された不凍液などの熱媒が循環する排熱回収回路である。この排熱回収回路２は、暖房用熱媒としての暖房水を排熱で加熱する排熱暖房熱交換器３と、循環ポンプ４とが設けられている。なお、暖房用熱媒は、水に限らず、不凍液などであってもよい。
【００２０】
５は暖房水を図示しない高温暖房端末や低温暖房端末に循環供給して高温暖房や低温暖房を行うとともに、浴槽６からの浴槽水を暖房水によって間接加熱して風呂の追焚きを行う熱源器としての給湯風呂暖房機であり、給水、給湯、暖房戻り、低温暖房端末および高温暖房端末用の各接続部５ａ〜５ｅを備えている。
【００２１】
この給湯風呂暖房機５は、図示しないバーナによって給水を加熱する給湯熱交換器７と、図示しないバーナによって暖房水を加熱する暖房熱交換器８と、暖房水を高温暖房端末あるいは低温暖房端末に送給する暖房ポンプ９と、暖房水を利用して浴槽水を加熱する風呂熱交換器１０と、浴槽６からの浴槽水を風呂熱交換器１０を介して循環させる風呂ポンプ１１と、浴槽６への給湯や給水を行うための電磁弁１２と、暖房水を風呂熱交換器１０を介して循環させるための電磁弁１３とを備えている。
【００２２】
この実施の形態では、従来例のように、排熱風呂熱交換器１８を追加することなく、排熱を回収して風呂の追焚きを行えるようにするために、次のように構成している。
【００２３】
すなわち、給湯風呂暖房機５の接続部５ｄから図示しない低温暖房端末を介して給湯風呂暖房機５の接続部５ｃに至る低温暖房循環回路には、その往き経路を分岐して戻り経路に合流させたバイパス経路１６が設けられており、戻り経路の合流位置よりも下流側であって、給湯風呂暖房機５の上流側に、排熱回収回路２の排熱暖房熱交換器３を配置している。また、往き経路の前記分岐させた位置には、三方弁１７が設けられており、この三方弁１７によって、暖房水の経路を、低温暖房端末側またはバイパス経路１６側に切換えることができるようになっている。なお、この三方弁１７およびガスエンジン１の駆動停止を含む各部の制御は、図示しないコントローラによって行われる。
【００２４】
次に、以上の構成を有する給湯風呂暖房システムの動作を、風呂の追焚き単独運転の場合と風呂の追焚きと暖房との同時運転の場合に分けて説明する。
（１）風呂の追焚き単独運転の場合
先ず、暖房することなく、ガスエンジン１の排熱を利用して風呂の追焚き運転を単独で行う場合には、ガスエンジン１を駆動するとともに、排熱回収回路２の循環ポンプ４を駆動してガスエンジン１からの熱媒を、矢符で示されるように排熱暖房熱交換器３を介して循環させる。
【００２５】
給湯風呂暖房機５では、電磁弁１３を開くとともに、三方弁１７をバイパス経路１６側に切換え、また、高温暖房端末への図示しない開閉弁を閉じるとともに、低温暖房端末（低温暖房循環回路）への図示しない開閉弁も閉じ、暖房ポンプ９および風呂ポンプ１１を駆動する。
【００２６】
これによって、暖房ポンプ９、暖房熱交換器８、電磁弁１３および風呂熱交換器１０を結ぶ内循環回路が構成される。この内循環回路は、暖房ポンプ９の下流側で分岐されて接続部５ｄを介して低温暖房循環回路に接続されている。
【００２７】
したがって、暖房ポンプ９からの暖房水は、暖房熱交換器８および接続部５ｄへと分流され、暖房熱交換器８への暖房水は、矢符で示されるように電磁弁１３を介して風呂熱交換器１０を経由して暖房ポンプ９へと戻り、また、接続部５ｄからの暖房水は、矢符で示されるように三方弁１７、バイパス経路１６および排熱暖房熱交換器３を介して接続部５ｃから暖房ポンプ９に戻る。
【００２８】
バイパス経路１６からの暖房水は、排熱暖房熱交換器３において、ガスエンジン１の７５℃〜８０℃程度の排熱で加熱されて暖房ポンプ９に戻るのであるが、その途中で、浴槽水との熱交換によって温度が低下した風呂熱交換器１０からの暖房水と合流されて温度が低下する。この温度が低下した暖房水は、暖房ポンプ９を経由して暖房熱交換器８および接続部５ｄへと分流され、接続部５ｄへ分流された暖房水は、再びバイパス経路１６を介して排熱暖房熱交換器３で排熱を回収する。
【００２９】
一方、排熱暖房熱交換器３で加熱されて暖房ポンプ９を経由して暖房熱交換器８へ分流された暖房水は、電磁弁１３を介して風呂熱交換器１０に至り、この風呂熱交換器１０で、浴槽水と熱交換して暖房ポンプ９に戻る。
【００３０】
このようにして、暖房水を、低温暖房循環回路のバイパス経路１６および排熱暖房熱交換器３を介して循環させることでガスエンジン１の排熱を回収する一方、暖房水を、内循環回路の風呂熱交換器１０を介して循環させることで浴槽水を間接加熱して風呂の追焚きを行うものである。
【００３１】
この実施の形態によれば、上述の従来例のように、排熱を回収して風呂の追焚きを行うために、排熱風呂熱交換器１８を追加する必要がなく、その分コストの低減を図ることができる。
【００３２】
さらに、この実施の形態では、ガスエンジン１の排熱の回収だけでは、風呂の追焚きの熱量が不足するような場合には、排熱回収と同時に、給湯風呂暖房機５の暖房熱交換器８の図示しないバーナを燃焼させて暖房水を加熱してもよい。
【００３３】
すなわち、この場合には、暖房熱交換器８の加熱によって、暖房水が、例えば、８０℃程度に加熱され、電磁弁１３を介して風呂熱交換器１０に至り、この風呂熱交換器１０で浴槽水と熱交換して加熱し、例えば、６０℃程度に温度が低下して排熱暖房熱交換器３からの暖房水と合流されて暖房ポンプ９に戻る。暖房ポンプ９を経由した暖房水は、暖房熱交換器８および接続部５ｄへと分流され、接続部５ｄへ分流された暖房水は、再びバイパス経路１６を介して排熱暖房熱交換器３で排熱を回収し、暖房熱交換器８へ分流された暖房水は、暖房熱交換器８の加熱によって、８０℃程度に加熱され、電磁弁１３を介して風呂熱交換器１０で浴槽水と熱交換して浴槽水を加熱するものである。
【００３４】
このように、暖房熱交換器８の加熱によって、例えば、８０℃程度に加熱された暖房水は、風呂熱交換器１０で浴槽水を加熱して温度が、例えば、６０℃程度に低下し、この温度が低下した暖房水が、暖房ポンプ９を介して分流されて再びバイパス経路１６を介して排熱暖房熱交換器３に至るので、ガスエンジン１の７５℃〜８０℃程度の排熱で再び加熱されることになり、ガスエンジン１の排熱による加熱と給湯風呂暖房機５の暖房熱交換器８による加熱とを併用できることになる。
（２）風呂の追焚きおよび暖房運転の場合
風呂の追焚きと高温あるいは低温暖房とを同時に行う場合には、基本的に従来と同様であり、三方弁１７は、図示しない低温暖房端末側へ切換えられ、バイパス経路１６は、使用されない。
【００３５】
給湯風呂暖房機５では、電磁弁１３を開くとともに、高温暖房端末あるいは低温暖房端末への図示しない開閉弁を開き、暖房ポンプ９および風呂ポンプ１１を駆動する。さらに、暖房熱交換器８の図示しないバーナを燃焼させて暖房水を加熱する。
【００３６】
これによって、従来と同様にして、暖房熱交換器８で加熱された暖房水が、電磁弁１３を介して風呂熱交換器１０に至り、この風呂熱交換器１０で浴槽水と熱交換して、浴槽水を間接加熱して追焚きを行うのである。
【００３７】
一方、暖房熱交換器８で加熱された８０℃程度の暖房水は、接続部５ｅを介して図示しない高温暖房端末に至り、この高温暖房端末で放熱した後、排熱暖房熱交換器３を介して給湯風呂暖房機５の接続部５ｃに戻る。あるいは、暖房熱交換器８で加熱された８０℃程度の暖房水は、分岐路１９を介して暖房端末からの温度の低い戻りの暖房水と合流されて例えば、６０℃程度の暖房水となり、暖房ポンプ９を経由して接続部５ｄへ分流され、三方弁１７を介して図示しない低温暖房端末に至り、この低温暖房端末で放熱した後、排熱暖房熱交換器３を介して給湯風呂暖房機５の接続部５ｃに戻る。
【００３８】
このとき、ガスエンジン１および循環ポンプ４を駆動してガスエンジン１の排熱によって、暖房端末からの戻りの暖房水を加熱して排熱を利用してもよい。
【００３９】
このようにして、給湯風呂暖房機５の暖房熱交換器８によって暖房水が加熱されて風呂の追焚きと高温あるいは低温暖房とが同時に行われる。
【００４０】
なお、低温暖房を行うことなく、高温暖房と風呂の追焚きとを同時に行う場合には、三方弁１７をバイパス経路１６側に切換えて暖房水を、バイパス経路１６を介して循環させるようにしてもよい。
【００４１】
（その他の実施の形態）
上述の実施の形態では、三方弁１７によって、暖房水の経路を切換えたけれども、本発明の他の実施の形態として、単に経路を切換えるのではなく、バイパス経路１６側と低温暖房端末側との流量を制御するようにしてもよい。
【００４２】
上述の実施の形態では、ガスエンジン１の排熱を回収したけれども、本発明の他の実施の形態として、燃料電池やマイクロガスタービンのような他の発電機の排熱を回収するようにしてもよいし、排熱に限らず、ボイラーその他の熱源の熱を回収するようにしてもよく、集合住宅におけるセントラルヒーティングシステムに用いてもよい。
【００４３】
【発明の効果】
以上のように本発明によれば、暖房用熱媒によって浴槽水を間接加熱する際には、低温暖房循環回路に設けたバイパス経路で暖房用熱媒を循環させることにより、熱回収回路の熱交換器によって、熱源からの熱を回収して暖房用熱媒を加熱できることなる。したがって、暖房用熱媒を加熱する熱交換器とは別に熱交換器を追加することなく、熱回収回路で回収した熱を利用して風呂の追焚きを行うことが可能となり、従来例に比べてコストの低減を図ることができる。
【００４４】
また、熱源から回収した熱だけでは、風呂の追焚きに不充分であるときには、熱源器の熱交換器で暖房用熱媒を加熱して追焚きを行うことが可能となる。しかも、熱源器の熱交換器で暖房用熱媒を加熱した場合にも、低温暖房循環回路へ供給される暖房用熱媒の温度は、高温暖房の場合に比べて低いので、この暖房用熱媒を熱回収回路の熱交換器で加熱することができ、熱源器の熱交換器および熱回収回路の熱交換器による暖房用熱媒の同時加熱が可能となる
【図面の簡単な説明】
【図１】本発明の実施の形態に係る給湯風呂暖房システムの概略構成図である。
【図２】従来例の給湯風呂暖房システムの概略構成図である。
【符号の説明】
１ガスエンジン
３排熱暖房熱交換器
８暖房熱交換器
９暖房ポンプ
１０風呂熱交換器
１６バイパス経路
１７三方弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat recovery system including a heat source device that recovers heat generated by a heat source such as a gas engine and heats a heating heat medium to be supplied and circulated to a heating terminal.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a system that has a hot water bath heater as a heat source and collects and uses exhaust heat from a heat source such as a gas engine, there is, for example, one shown in FIG.
[0003]
Hot water bath heaters 5 ₀ as a heat source instrument, water supply, hot water supply, return heating from the hot and cold the heating terminal, provided with a respective connecting portions 5 ₀ A～5 ₀ e for the low-temperature heating terminal and the high-temperature heating terminal A hot water supply heat exchanger 7 that heats feed water by a burner (not shown), a heating heat exchanger 8 that heats heating water as a heating heat medium by a burner (not shown), and a high-temperature heating terminal for heating or a low temperature A heating pump 9 that feeds the heating terminal, a bath heat exchanger 10 that heats the bath water using heating water, a bath pump 11 that feeds the bath water to the bathtub 6, and solenoid valves 12 and 13. I have.
[0004]
The exhaust heat recovery circuit 2 ₀ heat medium heated by the exhaust heat from a heat source such as a gas engine 1 is circulated, a circulation pump 4, the exhaust heat heater heat exchanger heating water return from the heating terminal is circulated 3 and an exhaust heat bath heat exchanger 18 in which the bath water circulates are provided, and the exhaust heat of the gas engine 1 is recovered to heat the heating water and the bath water.
[0005]
In such systems, when performing fired additionally bath using the exhaust heat of the gas engine 1, while circulating the bathtub water tub 6 by driving the hot-water bath heater 5 ₀ bath pump 11, gas engine 1 and the circulation pump 4 are driven to circulate the heat medium heated by the exhaust heat of the gas engine 1, and the bath water is directly heated by the exhaust heat bath heat exchanger 18 for reheating.
[0006]
Further, in the case of performing bath replenishment without using the exhaust heat of the gas engine 1, the heating pump 9 is driven to heat the heating water by the heating heat exchanger 8, and the electromagnetic valve 13 and the bath heat are heated. while circulating in the circulation circuit among returning to the heating pump 9 through the exchanger 10, indirect heating by heating water in the bath heat exchanger 10 by driving the water heater bath heater 5 ₀ bath pump 11 to circulate the bath water In this way, it is a memorial service.
[0007]
[Problems to be solved by the invention]
Thus, in the conventional system a bath additional heating of utilizing the waste heat of the heat source such as a gas engine 1, apart from the bath heat exchanger 10 of the hot water bath heater 5 _0, the exhaust heat recovery circuit 2 _0, It is necessary to add the exhaust heat bath heat exchanger 18 for directly heating the bath water, and there is a problem that the cost is high.
[0008]
The present invention has been made in view of the above-described points, and it is a main object of the present invention to make it possible to reheat a bath using heat recovered from a heat source without adding a heat exchanger.
[0009]
[Means for Solving the Problems]
The present invention is configured as follows in order to achieve the above-described object.
[0010]
That is, the heat recovery system according to the first aspect of the present invention includes a heat recovery circuit that recovers heat generated by a heat source and heats the heating heat medium, and a low temperature provided with the heating heat medium in the low-temperature heating circulation circuit. In a heat recovery system including a heat source that circulates and supplies water to the heating terminal and indirectly heats the bath water using a heating medium, a bypass route that branches the forward path of the low-temperature heating circulation circuit and joins the return path In addition, a heat exchanger of the heat recovery circuit for heating the heating medium is arranged on the downstream side of the merged position on the return path and on the upstream side of the heat source device.
[0011]
According to the first aspect of the present invention, when the bath water is indirectly heated by the heating heat medium, the heating heat medium is circulated through the bypass path provided in the low-temperature heating circulation circuit. The heat exchanger can recover the heat from the heat source and heat the heating medium. Therefore, it becomes possible to replenish the bath using the heat recovered by the heat recovery circuit without adding a heat exchanger separately from the heat exchanger for heating the heating heat medium.
[0012]
According to a second aspect of the present invention, in the first aspect of the invention, the heat source device heats the heating heat exchanger that heats the heating heat medium and bath water supplied and circulated from the bath by the heating heat medium. Bath heat exchanger, a heating pump that circulates the heating medium, and an internal circulation circuit inside the heat source device, the internal circulation circuit including the heating heat exchanger, the bath heat exchanger, and the heating When the pump is connected and branched and connected to the low-temperature heating circulation circuit to recover the heat generated by the heat source and reheat the bath, the heating medium is circulated in the internal circulation circuit. Circulates through the bypass path of the low-temperature heating circulation circuit.
[0013]
According to the second aspect of the present invention, the heating medium is circulated through the bypass path of the low-temperature heating circulation circuit branched from the internal circulation circuit to recover the heat generated by the heat source, while the internal circulation circuit By circulating through the bath heat exchanger, the bath water can be indirectly heated by the recovered heat to replenish the bath.
[0014]
According to a third aspect of the present invention, in the second aspect of the present invention, when the heat generated by the heat source is recovered and the bath is reheated, the heating heat exchanger is heated by the heating heat exchanger. Is what you do.
[0015]
According to the third aspect of the present invention, when only the heat recovered from the heat source is insufficient for reheating the bath, the reheating is performed by heating the heating medium with the heat exchanger of the heat source. Is possible. Moreover, even when the heating medium is heated by the heat exchanger of the heat source device, the temperature of the heating medium supplied to the low-temperature heating circulation circuit is lower than that in the case of high-temperature heating. The medium can be heated by the heat exchanger of the heat recovery circuit, and the heating heat medium can be simultaneously heated by the heat exchanger of the heat source circuit and the heat exchanger of the heat recovery circuit.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, details of the present invention will be described based on embodiments shown in the drawings.
[0017]
(Embodiment 1)
FIG. 1 is a schematic configuration diagram of a hot water bath heating system to which a heat recovery system according to one embodiment of the present invention is applied.
[0018]
In the figure, reference numeral 1 denotes a gas engine having a power generation function as a heat source, and electricity generated by the gas engine 1 is supplied to a household load of a general household where the hot water bath heating system is installed.
[0019]
Reference numeral 2 denotes an exhaust heat recovery circuit in which a heat medium such as antifreeze liquid heated by exhaust heat from the gas engine 1, for example, water cooling of the gas engine and exhaust gas of the gas engine circulates. The exhaust heat recovery circuit 2 includes an exhaust heat heating heat exchanger 3 that heats heating water as a heating heat medium with exhaust heat, and a circulation pump 4. The heating medium is not limited to water but may be an antifreeze or the like.
[0020]
A heat source 5 circulates and supplies heating water to a high-temperature heating terminal and a low-temperature heating terminal (not shown) to perform high-temperature heating and low-temperature heating, and heats the bathtub water from the bathtub 6 indirectly by heating water to replenish the bath As a hot water bath heater, it is provided with connecting portions 5a to 5e for water supply, hot water supply, heating return, low temperature heating terminal and high temperature heating terminal.
[0021]
The hot water bath heater 5 includes a hot water supply heat exchanger 7 that heats the water supply by a burner (not shown), a heating heat exchanger 8 that heats the heating water by a burner (not shown), and the heating water as a high temperature heating terminal or a low temperature heating terminal. Heating pump 9 for feeding, bath heat exchanger 10 for heating the bath water using heating water, bath pump 11 for circulating the bath water from bathtub 6 through bath heat exchanger 10, and bathtub 6 There are provided an electromagnetic valve 12 for supplying hot water and water and an electromagnetic valve 13 for circulating heating water through the bath heat exchanger 10.
[0022]
In this embodiment, as in the conventional example, in order to recover the exhaust heat and recharge the bath without adding the exhaust heat bath heat exchanger 18, the following configuration is provided. Yes.
[0023]
That is, in the low-temperature heating circulation circuit from the connection part 5d of the hot water bath heater 5 to the connection part 5c of the hot water bath heater 5 via a low-temperature heating terminal (not shown), the forward path is branched and joined to the return path. A bypass path 16 is provided, and the exhaust heat heating heat exchanger 3 of the exhaust heat recovery circuit 2 is arranged on the downstream side of the joining position of the return path and upstream of the hot water bath heater 5. Yes. In addition, a three-way valve 17 is provided at the branched position of the outgoing route so that the heating water route can be switched to the low temperature heating terminal side or the bypass route 16 side by the three-way valve 17. It has become. In addition, control of each part including the drive stop of this three-way valve 17 and the gas engine 1 is performed by a controller not shown.
[0024]
Next, the operation of the hot water bath heating system having the above configuration will be described separately for the case of bath renewal single operation and the case of simultaneous operation of bath renewal and heating.
(1) In the case of a bath renewal operation First, when performing a bath renewal operation using the exhaust heat of the gas engine 1 without heating, the gas engine 1 is driven and exhausted. The circulation pump 4 of the heat recovery circuit 2 is driven to circulate the heat medium from the gas engine 1 through the exhaust heat heating heat exchanger 3 as indicated by arrows.
[0025]
In the hot water bath heater 5, the electromagnetic valve 13 is opened, the three-way valve 17 is switched to the bypass path 16 side, the on-off valve (not shown) to the high temperature heating terminal is closed, and the low temperature heating terminal (low temperature heating circulation circuit) is opened. The on-off valve (not shown) is also closed, and the heating pump 9 and the bath pump 11 are driven.
[0026]
Thus, an internal circulation circuit connecting the heating pump 9, the heating heat exchanger 8, the electromagnetic valve 13, and the bath heat exchanger 10 is configured. This internal circulation circuit is branched downstream of the heating pump 9 and connected to the low-temperature heating circulation circuit via the connecting portion 5d.
[0027]
Therefore, the heating water from the heating pump 9 is diverted to the heating heat exchanger 8 and the connecting portion 5d, and the heating water to the heating heat exchanger 8 is bathed via the electromagnetic valve 13 as indicated by arrows. It returns to the heating pump 9 via the heat exchanger 10, and the heating water from the connecting portion 5d passes through the three-way valve 17, the bypass path 16, and the exhaust heat heating heat exchanger 3 as indicated by arrows. The connection part 5c returns to the heating pump 9.
[0028]
The heating water from the bypass passage 16 is heated by the exhaust heat of about 75 ° C. to 80 ° C. of the gas engine 1 in the exhaust heat heating heat exchanger 3 and returns to the heating pump 9. The temperature is lowered by merging with the heating water from the bath heat exchanger 10 whose temperature has been lowered by heat exchange with the water. The heating water whose temperature has been lowered is divided into the heating heat exchanger 8 and the connecting portion 5d via the heating pump 9, and the heating water divided into the connecting portion 5d is again exhausted through the bypass path 16. The exhaust heat is recovered by the heating heat exchanger 3.
[0029]
On the other hand, the heating water heated by the exhaust heat heating heat exchanger 3 and diverted to the heating heat exchanger 8 via the heating pump 9 reaches the bath heat exchanger 10 via the electromagnetic valve 13, and this bath heat. The exchanger 10 exchanges heat with the bath water and returns to the heating pump 9.
[0030]
In this way, the exhaust water of the gas engine 1 is recovered by circulating the heating water through the bypass path 16 of the low-temperature heating circulation circuit and the exhaust heat heating heat exchanger 3, while the heating water is supplied to the inner circulation circuit. The bath water is recirculated through the bath heat exchanger 10 so that the bath water is indirectly heated to replenish the bath.
[0031]
According to this embodiment, as in the above-described conventional example, it is not necessary to add the exhaust heat bath heat exchanger 18 in order to recover exhaust heat and replenish the bath, thereby reducing the cost accordingly. Can be achieved.
[0032]
Furthermore, in this embodiment, when the exhaust heat of the gas engine 1 alone is not sufficient to reheat the bath, the heating heat exchanger of the hot water bath heater 5 is simultaneously recovered with the exhaust heat recovery. The heating water may be heated by burning a burner (not shown).
[0033]
That is, in this case, the heating water is heated to, for example, about 80 ° C. by the heating of the heating heat exchanger 8 and reaches the bath heat exchanger 10 via the electromagnetic valve 13. Heat is exchanged with the bath water and heated. For example, the temperature is lowered to about 60 ° C., and the heating water from the exhaust heat heating heat exchanger 3 is joined and returned to the heating pump 9. The heating water that has passed through the heating pump 9 is diverted to the heating heat exchanger 8 and the connecting portion 5d, and the heating water that has been diverted to the connecting portion 5d is again sent to the exhaust heat heating heat exchanger 3 via the bypass path 16. Heating water recovered from the exhaust heat and diverted to the heating heat exchanger 8 is heated to about 80 ° C. by heating of the heating heat exchanger 8, and bath water is exchanged with the bath water exchanger 10 through the electromagnetic valve 13. It heat-exchanges and heats bathtub water.
[0034]
Thus, the heating water heated to, for example, about 80 ° C. by heating the heating heat exchanger 8 heats the bath water in the bath heat exchanger 10, and the temperature drops to, for example, about 60 ° C. The heating water whose temperature has been lowered is diverted through the heating pump 9 and reaches the exhaust heat heating heat exchanger 3 through the bypass path 16 again, so that the exhaust heat of the gas engine 1 is about 75 ° C. to 80 ° C. It will be heated again, and the heating by the exhaust heat of the gas engine 1 and the heating by the heating heat exchanger 8 of the hot water bath heater 5 can be used together.
(2) Bath rebirth and heating operation When bath rebirth and high-temperature or low-temperature heating are performed simultaneously, it is basically the same as in the prior art, and the three-way valve 17 is connected to a low-temperature heating terminal (not shown). The bypass path 16 is switched and not used.
[0035]
In the hot water bath heater 5, the solenoid valve 13 is opened, and an open / close valve (not shown) to the high temperature heating terminal or the low temperature heating terminal is opened to drive the heating pump 9 and the bath pump 11. Further, the heating water is heated by burning a burner (not shown) of the heating heat exchanger 8.
[0036]
As a result, the heating water heated by the heating heat exchanger 8 reaches the bath heat exchanger 10 via the electromagnetic valve 13 and exchanges heat with the bath water in the bath heat exchanger 10 in the same manner as before. In addition, the bath water is heated indirectly to reheat.
[0037]
On the other hand, the heating water at about 80 ° C. heated by the heating heat exchanger 8 reaches a high-temperature heating terminal (not shown) via the connecting portion 5e, and after radiating heat at the high-temperature heating terminal, the exhaust heat heating heat exchanger 3 is Through the connecting part 5c of the hot water bath heater 5. Alternatively, the heating water of about 80 ° C. heated by the heating heat exchanger 8 is merged with the return heating water having a low temperature from the heating terminal via the branch path 19 to become heating water of about 60 ° C., for example. It is diverted to the connecting part 5d via the heating pump 9, reaches a low-temperature heating terminal (not shown) via the three-way valve 17, radiates heat at this low-temperature heating terminal, and then hot water bath heating via the exhaust heat heating heat exchanger 3 Return to the connection 5c of the machine 5.
[0038]
At this time, the exhaust heat may be used by driving the gas engine 1 and the circulation pump 4 to heat the heating water returned from the heating terminal by the exhaust heat of the gas engine 1.
[0039]
In this way, the heating water is heated by the heating heat exchanger 8 of the hot-water bath heater 5 so that the reheating of the bath and high-temperature or low-temperature heating are performed simultaneously.
[0040]
In addition, when performing high temperature heating and bath retreat simultaneously without performing low temperature heating, the three-way valve 17 is switched to the bypass path 16 side so that the heating water is circulated through the bypass path 16. Also good.
[0041]
(Other embodiments)
In the above-described embodiment, the route of the heating water is switched by the three-way valve 17. However, as another embodiment of the present invention, the route is not simply switched, but the bypass route 16 side and the low temperature heating terminal side are switched. The flow rate may be controlled.
[0042]
In the above-described embodiment, the exhaust heat of the gas engine 1 is recovered. However, as another embodiment of the present invention, the exhaust heat of another generator such as a fuel cell or a micro gas turbine is recovered. Alternatively, the heat of the boiler or other heat source is not limited to exhaust heat, and may be used for a central heating system in an apartment house.
[0043]
【The invention's effect】
As described above, according to the present invention, when the bathtub water is indirectly heated by the heating medium, the heating medium is circulated through the bypass path provided in the low-temperature heating circulation circuit, thereby heat of the heat recovery circuit. The exchanger can recover the heat from the heat source and heat the heating medium. Therefore, without adding a heat exchanger separately from the heat exchanger that heats the heating medium, it is possible to reheat the bath using the heat recovered by the heat recovery circuit, compared to the conventional example. The cost can be reduced.
[0044]
Further, when the heat recovered from the heat source alone is insufficient for reheating the bath, the reheating can be performed by heating the heating medium with the heat exchanger of the heat source. Moreover, even when the heating heat medium is heated by the heat exchanger of the heat source device, the temperature of the heating medium supplied to the low-temperature heating circulation circuit is lower than that in the case of high-temperature heating. The medium can be heated by the heat exchanger of the heat recovery circuit, and the heating medium can be simultaneously heated by the heat exchanger of the heat source and the heat exchanger of the heat recovery circuit. [Brief Description of Drawings]
FIG. 1 is a schematic configuration diagram of a hot water bath heating system according to an embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of a conventional hot water bath heating system.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Gas engine 3 Waste heat heating heat exchanger 8 Heating heat exchanger 9 Heating pump 10 Bath heat exchanger 16 Bypass path 17 Three-way valve

Claims

A heat recovery circuit that recovers the heat generated by the heat source and heats the heating medium, and circulates and supplies the heating medium to the low-temperature heating terminal provided in the low-temperature heating circulation circuit, and supplies the bathtub water to the heating medium. In a heat recovery system comprising a heat source device indirectly heated by
Provided is a bypass path that branches the forward path of the low-temperature heating circulation circuit and merges with the return path, and is located downstream of the merged position of the return path and upstream of the heat source unit. A heat recovery system in which a heat exchanger of the heat recovery circuit for heating the heat medium is disposed.

The heat recovery system according to claim 1,
The heat source device includes a heating heat exchanger that heats a heating heat medium, a bath heat exchanger that heats bath water supplied and circulated from a bath by the heating heat medium, and a heating pump that circulates the heating heat medium. And an internal circulation circuit inside the heat source device,
The internal circulation circuit connects the heating heat exchanger, the bath heat exchanger and the heating pump, and is branched and connected to the low temperature heating circulation circuit,
When recovering the heat generated by the heat source and reheating the bath, the heating medium is circulated in the internal circulation circuit, and is circulated through the bypass path of the low-temperature heating circulation circuit. Features a heat recovery system.

The heat recovery system according to claim 2,
When the heat generated by the heat source is recovered to replenish the bath, the heating heat medium is also heated by the heating heat exchanger.