JP4091852B2 - Triple effect absorption chiller / heater with waste heat regenerator - Google Patents

Description

【００１６】
この表１に示されるように、冷房負荷と発電負荷のバランスが変わると運転条件が変わり、特に吸収式冷温水機側の内部を循環する吸収液の温度条件が変わる。そのため、一部の温度条件だけを監視する制御では、効率の良い熱回収と吸収式冷温水機の省エネルギー運転を行い難いことが分かる。
【００１７】
従来、二重効用形吸収式冷温水機としては、冷水出口温度又は冷水入口温度を検知して、加熱量を制御する制御であって、排熱温水が排熱回収器へ入る際の入口温度を制御して吸収式冷温水機の熱回収量を制御する制御方式が発明されている（例えば、特許文献１、特許文献２参照）。しかし、吸収式冷温水機の負荷制御及び排熱回収制御に加えて、戻りの温度を検知して排熱を発生する設備側（例えば、ガスエンジン）への影響を考慮した制御回路（方式）は提案されていない。
【００１８】
【特許文献１】
特開平１１−８３２２８号公報（第２頁、図２）
【特許文献２】
特開２０００−６５４３６号公報（第２頁、図１）
【００１９】
【発明が解決しようとする課題】
外部排熱を利用して熱回収する吸収式冷温水機の制御では、通常は、吸収式冷温水機の冷温水出口温度を検出して外部から供給される排熱量の制御と、冷温水機自身が持つ燃焼機器の燃焼量の制御が行われる。すなわち、冷房負荷が高い時は排熱を全量回収し、燃焼量を増減して冷温水出口温度が一定になるように制御し、冷暖房負荷が減り排熱だけで運転が可能になると、燃焼機器への燃料供給を遮断して排熱だけを熱源として冷暖房運転を行う。
吸収式冷温水機単体で見ると、通常の冷暖房負荷の増減に対応する制御で何ら問題がない。しかし、排熱を発生し、この排熱を吸収式冷温水機に供給する設備側の負荷、すなわち、発電機とセットで運転しているガスエンジンなど排熱源の負荷の影響も、同時に検討しないと最適な制御とは言えず、運転も不安定なものになりやすい。
しかしながら、これらの点を考慮し、二重効用形吸収式冷温水機よりもさらに効率を上げて省エネルギー化を進めた三重効用形吸収式冷温水機及びその制御装置は提案されていない。
【００２０】
本発明は上記の諸点に鑑みなされたもので、本発明の目的は、外部排熱再生器を組み込んだ三重効用形吸収式冷温水機において、外部排熱を有効に回収し、かつ、戻りの排熱温水の温度低下によるその他の熱源機器（コージェネレーションシステムの例ではガスエンジンなど）への影響を減らすように考慮したもので、従来から知られている熱回収方法に加えて、排熱回収時の制御性と回収効率を高め、さらに、排温水の戻り側の機器（排温水を発生する熱源機でもあるガスエンジンなどの機器）の効率を高めるよう配慮した排熱再生器を有する三重効用形吸収式冷温水機を提供することにある。
【００２１】
【課題を解決するための手段】
上記の目的を達成するために、本発明の排熱再生器を有する三重効用形吸収式冷温水機は、貫流方式ボイラ又は貫流方式ボイラと同等の構造を持つボイラを高温再生器として、この高温再生器と二重効用形吸収式冷温水機とを一体化した三重効用形吸収式冷温水機であって、高温再生器、中温再生器、低温再生器、凝縮器、吸収器、蒸発器、熱交換器類、溶液ポンプ及び冷媒ポンプを少なくとも有し、吸収器の吸収液を低温再生器から中温再生器へ、ついで高温再生器へ導くリバースフロー式の三重効用形吸収式冷温水機において、外部からの排熱を回収し加熱源として有効に利用して、吸収液を加熱し吸収液に吸収されている冷媒を加熱蒸発させて吸収液の濃度を上げるための排熱再生器を、低温再生器の手前に設け、低温再生器で吸収液を加熱し吸収液の濃度を上げる加熱熱量の割合を、外部から回収する排熱量を増減させて減少させることにより、低温再生器の熱交換量を低減させて、高温再生器及び中温再生器で発生させ吸収液を加熱・濃縮し低温再生器の加熱源となる冷媒蒸気の発生量を減らしても性能に影響が無いようにして、高温再生器での加熱に使用する燃料消費量を減らし、省エネルギーを図るようにしたことを特徴としている。
【００２２】
この三重効用形吸収式冷温水機において、低温再生器で吸収液を加熱し吸収液の濃度を上げる加熱熱量の割合を、外部から回収する排熱量を増減させて、１５〜４０％減少させるようにすることが好ましい。
また、排熱再生器を設けない場合の三重効用形吸収式冷温水機に比べ、本発明におけるように排熱再生器を設けることにより高温再生器での加熱に使用する燃料消費量を１５〜３０％減らし、省エネルギーを図るようにしている。
また、外部排熱を回収して排熱再生器の熱源とするための排温水制御弁、排温水管路及び排温水制御器が設けられている。
【００２３】
また、排熱再生器入口の排温水温度が排熱再生器内で加熱させる吸収液温度より所定の温度（例えばプラス３℃）高い時に、排温水制御弁を制御して排温水が排熱再生器に流入し、吸収液を加熱するように構成されている。
さらに、排温水の温度が、外部排熱を発生させる熱源となっている熱源システム機器（例えばガスエンジン）の運転条件及び効率に悪影響を与えない温度（例えば６０℃以上）になるように、戻りの排温水温度を排温水制御弁を用いて制御して、排温水が排熱再生器に流入し、吸収液を加熱するように構成されている。また、排熱再生器入口に排熱温水の流量制御を行う排温水三方制御弁を設けたり、排熱再生器出口に排熱温水の流量制御を行う排温水三方制御弁を設けたりして構成することが好ましい。
【００２４】
吸収器の吸収液ポンプ出口と蒸発器とを、流量調節弁を有する吸収液分配管を介して接続し、蒸発器の冷水出口管又は冷水入口管に設けた温度センサーとこの流量調節弁とを制御装置（制御盤）を介して、温度センサーで検出された温度により蒸発器に流入させる吸収液量を制御可能とし、さらに、蒸発器冷媒溜まりに溜まった冷媒と流入した吸収液を、蒸発器に設けたオーバーフロー用堰又はオーバーフロー管から吸収器液溜まりに流下させるか、又は戻すように構成されている。
【００２５】
排熱再生器に排温水を流し、排熱を回収する燃焼熱量削減運転中で、かつ、高温再生器の燃焼装置で追い焚き燃焼運転をする必要がない部分負荷運転時は、排熱回収量をできるだけ多くするように、吸収液ポンプの運転は定格運転にして吸収液循環量を増やすように制御し、負荷が増えて追い焚き燃焼運転が必要になった場合には負荷に応じて効率良く運転する吸収液循環量となるように、吸収液ポンプの吐出量を制御するように構成されている。
また、排熱再生器に排温水を流し、排熱を回収する燃焼熱量削減運転中で、かつ、高温再生器の燃焼装置で追い焚き燃焼運転をする部分負荷運転時、負荷変動などにより高温再生器内の溶液液面が変動して空缶運転や液面低による安全停止を起さないように、吸収液ポンプの吐出量を制御して高温再生器への吸収液循環量を確保し、連続して安定した運転ができるように構成されている。
【００２６】
排熱再生器として、チューブ内を加熱流体（排温水）が流れ、チューブ外を稀吸収液が流れるプール沸騰方式のシェル・アンド・チューブ型熱交換器を用いるように構成することが好ましい。
この場合、プール沸騰方式のシェル・アンド・チューブ型熱交換器の稀吸収液流出口が、シェル・アンド・チューブ型熱交換器を構成している伝熱管群の最上段近傍に設けられ、前記伝熱管群の最上段とその下の段の伝熱管の配置が、吸収液に添加されている表面活性剤の前記稀吸収液流出口からの流出を阻害しないようにされる。
また、排熱再生器の最上段とその下の段の伝熱管の配置が、碁盤目配列とされていることが好ましい。
【００２７】
さらに、排熱再生器から低温再生器への冷媒蒸気ラインに、蒸発器の加熱側に接続する分岐ラインを設けるとともに、該分岐ラインに冷房用と暖房用とに切り替えるための冷暖切替手段を設け、該冷暖切替手段を暖房用に切り替えて前記排熱再生器からの冷媒蒸気を蒸発器に導いて、蒸発器内の伝熱管内を流れる温水を加熱するように構成されている。
【００２８】
上記のように、外部から供給される排熱を有効に回収して省エネルギー化を図る三重効用形吸収式冷温水機において、この外部排熱を有効に回収し、かつ、排熱を発生する設備側への影響を無くす理想的な運転を可能とするために、吸収式冷温水機の冷水出口（入口）温度を検知して加熱量を制御する従来の負荷制御に加え、外部排熱をできるかぎり回収し、かつ、排熱を発生する設備側への影響を無くすように、排熱の戻り温度を制御する排熱回収量制御回路と、冷水出口（入口）温度の下がり過ぎを防止するために吸収液を蒸発器（冷媒溜まり）へ流入させるように接続する吸収液配管と、その配管途中に装備する吸収液制御弁を設けている。
【００２９】
これらの三重効用形吸収式冷温水機において、負荷（冷温水）の温度変化によって燃焼装置の燃焼量（加熱量）を増減するのと同時に、ボイラ内部の蒸気圧が上昇し温度が上昇して、蒸気で加熱される吸収冷凍機の中温再生器出口部の蒸気ドレン温度センサで検出する温度が上昇した場合には、安全のため吸収液供給ポンプの回転数を上げて、液循環量を増加させてその結果蒸気圧を下げるようにし、ドレン温度が低下すれば吸収液供給ポンプの回転数を下げて液循環量を減らして蒸気圧を上げるようにし、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるようにした制御機能を持つように構成する。
【００３０】
また、負荷（冷温水）の温度変化によって燃焼装置の燃焼量（加熱量）を増減するのと同時に、ボイラ内部の蒸気圧が上昇し温度が上昇して、ボイラ出口部の蒸気配管で検出される、蒸気圧力又は温度センサで検出する温度が上昇した場合には、安全のため吸収液供給ポンプの回転数を上げて、液循環量を増加させてその結果蒸気圧を下げるようにし、蒸気圧力又は温度が低下すれば吸収液供給ポンプの回転数を下げて液循環量を減らして蒸気圧を上げるようにし、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるようにした制御機能を持つように構成する。
【００３１】
これらの冷温水機において、ボイラの運転中の液面を液面検出装置により検出して、液面が上昇した場合にはポンプの回転数を減らし、液循環量を減らして液面が下がるようにし、液面が低下した場合には、ポンプの回転数を増やして液循環量を増やし液面が上がるように制御し、また、運転液面が安全運転の下限設定値よりさらに低下した場合には警報を発し燃焼を遮断して安全停止動作に入るようにした安全制御機能を持つように構成する。
また、運転中の蒸気ドレン温度、蒸気温度、蒸気圧力又はボイラの運転液面を検出して、ポンプの回転数を制御する場合に、制御は低温吸収液ポンプ、高温吸収液ポンプ、水・吸収液供給ポンプの各ポンプを同時に、もしくは単独に、又は低温吸収液ポンプと水・吸収液供給ポンプの２台だけのような組合せの中から選択した運転方法から１方式を又は複数の方式を切り替えられるようにして、回転数制御をして水を含む吸収液の供給量（循環量）を制御し運転効率を高めるようにして、かつ各ポンプが供給量（循環量）不足や揚程不足を起こさない回転数を確保するように制御するように構成する。
【００３２】
これらの冷温水機において、運転中に、ボイラへの水・吸収液を供給する供給装置が故障して、供給量が減少した場合には、ボイラ内部に保有する水・吸収液量が減少して連続運転に支障を生じるので、警報を発すると同時に燃焼を遮断して、安全停止動作に入るようにした安全制御機能を持つ構成とする。
また、運転中に、ボイラへの水・吸収液供給量が減少した場合や、ボイラ内部に保有する水・吸収液量が減少して各部の温度が安全運転の設定値を越えた場合には、ボイラに設けた吸収液温度センサや空缶防止吸収液温度センサにより警報を発すると同時に燃焼を遮断して、安全停止動作に入るようにした安全制御機能を持つ構成とする。
【００３３】
さらに、ボイラが、加熱されて蒸発した蒸気、蒸発しなかった吸収液及びボイラに再循環する水を含む吸収液をそれぞれ分離して連続運転が可能となるよう蒸気、吸収液を分配する気液分離器を備えるボイラである構成とする。
【００３４】
上記の吸収式冷温水機の制御方法は、ボイラと吸収冷凍機とを一体化した吸収式冷温水装置において、冷温水温度センサから負荷側の温度変化を検出し、その温度変化を運転制御・安全制御用運転盤（運転盤）からの制御信号によりボイラに供給される燃料（ガス、油、廃熱）を増減し、燃焼装置の燃焼量を増減してボイラの効率的な運転を行い、同時に吸収冷凍機の各吸収液ポンプを運転して、水の含有割合の異なる吸収液を安定的に供給（循環）して連続運転を可能とし、低温再生器から上位の再生器に液を供給する吸収液ポンプに流入する吸収液の一部を分岐して戻り配管にバイパスさせ、同時に中温再生器から水・吸収液供給ポンプに流入する液の一部を分岐して戻り配管にバイパスさせ、水・吸収液（吸収液）の供給量（循環量）を調整して、ポンプに掛かる動力負荷を調整して、省エネルギと安定した連続運転を行うものである。
【００３５】
この方法において、負荷（冷温水）の温度変化によって燃焼装置の燃焼量（加熱量）を増減するのと同時に、ボイラ内部の蒸気圧が上昇し温度が上昇して、蒸気で加熱される吸収冷凍機の高温再生器出口部の蒸気ドレン温度センサで検出する温度が上昇した場合には、安全のため吸収液供給ポンプの回転数を上げて、液循環量を増加させてその結果蒸気圧を下げ、ドレン温度が低下すれば吸収液供給ポンプの回転数を下げて液循環量を減らして蒸気圧を上げ、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるように制御するように構成する。
【００３６】
また、負荷（冷温水）の温度変化によって燃焼装置の燃焼量（加熱量）を増減するのと同時に、ボイラ内部の蒸気圧が上昇し温度が上昇して、ボイラ出口部の蒸気配管で検出される、蒸気圧力又は温度センサで検出する温度が上昇した場合には、安全のため吸収液供給ポンプの回転数を上げて、液循環量を増加させてその結果蒸気圧を下げ、蒸気圧力又は温度が低下すれば吸収液供給ポンプの回転数を下げて液循環量を減らして蒸気圧を上げ、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるように制御するように構成する。
【００３７】
これらの方法において、ボイラの運転中の液面を液面検出装置により検出して、液面が上昇した場合にはポンプの回転数を減らし、液循環量を減らして液面を下げ、液面が低下した場合には、ポンプの回転数を増やして液循環量を増やし液面を上げるように制御し、また、運転液面が安全運転の下限設定値よりさらに低下した場合には警報を発し燃焼を遮断して安全停止動作に入るように制御する。
【００３８】
この方法において、ボイラの運転中の液面を液面検出装置により検出して、ポンプの回転数を制御する方法として、運転条件、制御信号を受けて、あらかじめ定めた回転数に段階的に変化させるようにした段階制御式を用いる方法としたり、又は、ボイラの運転中の液面を液面検出装置により検出して、ポンプの回転数を制御する方法として、運転条件、負荷信号、制御信号を受けて、連続的に回転数を変化させるようにした連続制御式を用いる方法とする。
【００３９】
これらの方法において、運転中の蒸気ドレン温度、蒸気温度、蒸気圧力又はボイラの運転液面を検出して、ポンプの回転数を制御する場合に、制御は低温吸収液ポンプ、高温吸収液ポンプ、水・吸収液供給ポンプの各ポンプを同時に、もしくは単独に、又は低温吸収液ポンプと水・吸収液供給ポンプの２台だけのような組合せの中から選択した運転方法から１方式を又は複数の方式を切り替えられるようにして、回転数制御をして水を含む吸収液の供給量（循環量）を制御し運転効率を高め、かつ各ポンプが供給量（循環量）不足や揚程不足を起こさない回転数を確保するように制御する。
【００４０】
これらの方法において、運転中に、ボイラへの水・吸収液を供給する供給装置が故障して、供給量が減少した場合には、ボイラ内部に保有する水・吸収液量が減少して連続運転に支障を生じるので、警報を発すると同時に燃焼を遮断して、安全停止動作に入るように制御する。
また、運転中に、ボイラへの水・吸収液供給量が減少した場合や、ボイラ内部に保有する水・吸収液量が減少して各部の温度が安全運転の設定値を越えた場合には、ボイラに設けた吸収液温度センサや空缶防止吸収液温度センサにより警報を発すると同時に燃焼を遮断して、安全停止動作に入るように制御する。
【００４１】
これらの方法において、ボイラとして、加熱されて蒸発した蒸気、蒸発しなかった吸収液及びボイラに再循環する水を含む吸収液をそれぞれ分離して連続運転が可能となるよう蒸気、吸収液を分配する気液分離器を備えるボイラを用いるように構成する。
【００４２】
【発明の実施の形態】
以下、本発明の実施の形態について説明するが、本発明は下記の実施の形態に何ら限定されるものではなく、適宜変更して実施することができるものである。
図１は、本発明の実施の第１形態による吸収式冷温水機を示し、図２は液面検出・制御装置まわりを示し、図３は液面検出・制御装置の詳細を示している。高温再生器としては、貫流方式ボイラ又はこれと同等の機能、構造を有するボイラが用いられるが、本実施形態では、高温再生器として貫流式ボイラ形のものを用いる場合を示している。１０は貫流式ボイラ構造の高温再生器で、上部と下部に環状の上部管寄せ（上部ヘッダー）１２及び下部管寄せ（下部ヘッダー）１４を有し、これらの管寄せ１２、１４間に鉛直方向の多数の上昇管１６を略円筒状に配設し、上部中央部に燃焼装置１８、例えばバーナーを有し、稀吸収液を下部管寄せ１４に導入して加熱濃縮し、上部管寄せ１２から気液混合物を取り出すことができるように構成されている。２０は燃焼室である。
【００４３】
この高温再生器１０に気液混合物導管２４を介して気液分離器２６が接続されている。気液分離器２６の上部には冷媒蒸気管２８が接続され、気液分離器２６の下側部には吸収液抜出導管３０が接続されている。
気液分離器２６の下部と高温再生器１０の下部管寄せ１４とは、吸収液循環導管３６を介して接続されている。吸収液循環導管３６又は下部管寄せ１４には、吸収液供給管４２が接続されている。４３は気液分離器２６の液面検出装置である。また、下部管寄せ１４の下面又は側面には、空缶防止用の吸収液温度センサ（図示略）が設けられている。
【００４４】
本実施形態は、吸収器８１、低温吸収液ポンプ８２、低温熱交換器８３、低温再生器８４、中間吸収液ポンプ８５、中温熱交換器８６、中温再生器８７、凝縮器８８、蒸発器８９、冷媒ポンプ９０及びこれらの機器を接続する吸収液配管、冷媒配管等を構成要素とするリバースサイクル式の二重効用形吸収式冷凍機に対し、貫流式ボイラ構造の高温再生器１０、溶液供給手段としての高温吸収液ポンプ９３、高温熱交換器９４等を組み合わせて一体化したものである。４８は吸収式冷温水機である。なお、図１において、実線に付した矢印は吸収液、冷媒液又は水の流れ方向を示し、破線に付した矢印は冷媒蒸気、又は冷媒蒸気と凝縮冷媒（冷媒ドレン）との混合物の流れ方向を示す。
【００４５】
９５は第一バイパス管で、低温再生器８４からの吸収液の一部を中温熱交換器８６からの濃吸収液配管にバイパスさせるためのものである。また、９６は第二バイパス管で、中温再生器８７からの吸収液の一部を高温熱交換器９４からの戻り濃吸収液配管にバイパスさせるためのものである。９９は冷温水ポンプ、１００は冷却水ポンプ、１５１は第一冷暖切替弁である。なお、中温再生器８７と高温再生器１０との間に別の濃縮器を設置することも可能である。
【００４６】
さらに、低温吸収液ポンプ８２の出口管は分岐し、一方の分岐吸収液管１６０は、蒸発器８９の冷媒液溜まり１６２に接続され、この分岐吸収液管１６０に吸収液流量制御弁１６４が設けられ、この弁１６４は運転制御・安全制御用運転盤１１４に接続されている。
【００４７】
低温吸収液ポンプ８２からの他方の分岐吸収液管１６６は低温熱交換器８３に接続され、吸収液はこの低温熱交換器８３で加熱された後、排熱再生器１６８に導入され、この排熱再生器１６８には、ガスエンジン、ガスタービン、焼却炉などの外部の熱源機器の排熱により発生させられた排温水が熱源として供給されている。
【００４８】
そして、排温水入口管１７０及び排温水出口管１７２には、それぞれ温水温度センサー１７４、１７６が設けられ、これらのセンサー１７４、１７６と運転盤１１４とが接続されている。また、排水温度入口管１７０又は／及び排水温度出口管１７２に、例えば三方制御弁である排温水流量制御弁１７８が設けられ、この制御弁１７８と運転盤１１４とが接続されている。さらに、排熱再生器１６８の入口の吸収液管１８０には吸収液温度センサー１８２が設けられ、このセンサー１８２と運転盤１１４とが接続されている。１８４は第二冷暖切替弁、１８６は冷媒ドレン熱交換器、１８８は排ガス熱交換器である。１９０は蒸発器８９の冷媒液溜まり１６２に設けられたオーバーフロー用堰である。なお、堰の代りにオーバーフロー管を用いることも可能である。
【００４９】
つぎに、上記のように構成された吸収式冷温水機において、吸収液の循環サイクルについて順に説明する。まず、吸収器８１で多量の冷媒蒸気を吸収して濃度が薄められた稀吸収液が、低温吸収液ポンプ８２の出口管は分岐しており、一方は吸収器８１から低温熱交換器８３に送給され、この低温熱交換器８３により加熱された後に、排熱再生器１６８に導入され、一方は蒸発器８９の冷媒液溜まり１６２に接続されている。排熱再生器１６８に供給された稀吸収は、排温水により加熱されて再生され、吸収している冷媒の一部を放出し濃度がその分高くなって、吸収液管１９２を介して低温再生器８４へ送られる。排熱再生器１６８からの冷媒蒸気は吸収液を含み、冷媒蒸気管１９４、１９６を介して低温再生器８４及び蒸発器８９へ送られる。蒸発器への冷媒蒸気管１９６には第二冷暖切替弁１８４が設けられている。
【００５０】
低温再生器８４において低温再生された中間濃縮吸収液の大部分は、低温再生器８４から中温吸収液ポンプ８５によって中温熱交換器８６に送給され、この中温熱交換器８６により加熱された後に中温再生器８７に送給される。この中間濃縮吸収液は、この中温再生器８７において再生され、吸収している冷媒の一部を放出し濃度がさらに高くなって高濃度の濃吸収液となる。
低温再生器８４からの中間濃縮吸収液の残部は、吸収器８１へ戻る濃吸収液配管にバイパス管９５を経てバイパス供給される。
【００５１】
中温再生器８７からの濃吸収液の一部又は全部は、高温吸収液ポンプ９３により高温熱交換器９４へ送給され、ここで、高温再生器１０からの濃吸収液と熱交換して加熱された後、高温再生器１０に供給される。中温再生器８７からの濃吸収液の残部（零の場合もあり得る）は、第二バイパス管９６を経て高温熱交換器９４からの加熱側の吸収液配管に合流する。
【００５２】
高温再生器１０において、ガス燃料などの燃料の燃焼熱により加熱濃縮された濃吸収液は、高温熱交換器９４の加熱側に導入されて中温再生器８７からの濃吸収液を加熱した後、中温熱交換器８６の加熱側に導入される。中温再生器８７からの濃吸収液の残部（零の場合もあり得る）は、第二バイパス管９６を経て高温熱交換器９４からの加熱側の吸収液配管に合流する。
高温再生器１０からの冷媒蒸気は冷媒蒸気管２８を経て中温再生器８７へ導入され、ここで吸収液を加熱濃縮させた後、冷媒ドレンは低温再生器８４へ導入される。
【００５３】
中温再生器８７からの冷媒蒸気は冷媒蒸気管９７を経て、中温再生器８７からの冷媒ドレンとともに低温再生器８４に送られ、ここで吸収液を加熱濃縮させる。
低温再生器８４からの冷媒蒸気は冷媒蒸気管９８を経て凝縮器へ、低温再生器８４からの冷媒ドレンは冷媒ドレン熱交換器１８６で、排熱再生器へ送給される稀吸収液の一部を加熱した後、凝縮器８８に導入される。なお、高温再生器１０からの燃焼排ガスを排ガス熱交換器（図示略）に導入して、吸収液又は冷媒を加熱し、排ガスの保有熱を回収するように構成している。
【００５４】
また、冷温水取出管に冷温水温度センサー１０２が設けられ、中温再生器８７からの蒸気ドレン管に蒸気ドレン温度センサー（図示略）が設けられ、気液分離器２６からの吸収液抜出導管３０に吸収液温度センサー（図示略）が設けられ、冷媒蒸気管２８に蒸気温度センサー（図示略）、圧力計（圧力センサー（図示略））が設けられている。蒸気ドレン温度センサー、蒸気温度センサー、蒸気圧力センサーは同時に設けるのではなく、どれか１つを選択して設ければよい。また、２つ以上設けてもよい。また、前述のように、高温再生器１０の下部管寄せ１４の下面に空缶防止用の吸収液温度センサー（図示略）が設けられている。
【００５５】
また、前述のように、運転制御・安全制御用運転盤１１４が設けられ、この運転盤１１４と、吸収液流量制御弁１６４、温水温度センサー１７４、１７６、排温水流量制御弁１７８、吸収液温度センサー１８２、冷温水温度センサー１０２、蒸気ドレン温度センサー、気液分離器の液面検出装置４３、燃焼装置１８、気液分離器出口の吸収液温度センサー、空缶防止用の吸収液温度センサー、低温吸収液ポンプ８２、中温吸収液ポンプ８５、高温吸収液ポンプ９３、冷媒蒸気管２８の蒸気温度センサー、圧力計（圧力センサー）、排ガス温度センサーとが連動接続されて、これら各部の温度、圧力、流量等が制御できるように構成されている。なお、蒸気ドレン温度センサー、蒸気温度センサー、蒸気圧力センサーは同時に設けるのではなく、どれか１つを選択して設ける。また、２つ以上設けてもよい。
【００５６】
さらに、前述のように、高温再生器１０の排ガス通路に排ガス熱交換器が設けられ、この排ガス熱交換器に、例えば、低温再生器から中温再生器に液を供給する吸収液ポンプからの吸収液の一部を導入して排ガスで加熱するように構成される。なお、吸収液の代りに燃焼用空気を導入し排ガスで加熱するように構成することも可能である。この排ガス熱交換器の出口の排ガス通路に排ガス温度センサー（図示略）が設けられている。
この排ガス温度センサーと前記運転制御・安全制御用運転盤１１４とは制御ラインで連動接続され、前記高温再生器１０の気液混合物導管２４に接続された気液分離器２６に、高温再生器１０の液面を制御するための液面検出・制御装置４４が設けられている。
【００５７】
液面検出・制御装置４４は、図２及び図３に示すように、気液分離器２６に上部液出入り管１２８及び下部液出入り管１３０を介して接続された鉛直管１３２（例えば、金属管）内の液面１３４に、マグネット１３６を内蔵したフロート１３８を浮かべ、鉛直管１３２の外面に高位液面検出スイッチ１４０及び低位液面検出スイッチ１４２を取り付け、この高位液面検出スイッチ１４０は高温再生器の上部管寄せ１２の管板面１２６の高さ近傍に位置しており、これらのスイッチ１４０、１４２がフロート１３８に内蔵されたマグネット１３６の磁力により作動し、液面変化を電気信号として検出し、該信号を前記運転制御・安全制御用運転盤１１４へ液面を知らせる制御信号として伝達されるように構成されている。
【００５８】
さらに、前記運転制御・安全制御用運転盤１１４が、起動時に液面検出・制御装置４４が「高」スイッチの作動を確認しなければ、液面検出・制御装置４４が異常であると運転制御・安全制御用運転盤１１４が判断して、運転に入らず警報を出し、また燃焼運転に入らないように制御する制御回路を備えて構成されている。
【００５９】
また、前記運転制御・安全制御用運転盤１１４に点検用のテスト運転モードを設け、このテスト運転モードに切り換えてから起動すると、自動運転制御回路により運転を開始しボイラ圧力または蒸気温度が設定値に上がるまで自動運転を行い、設定値に達すると安全のため先に燃焼を止める。燃焼停止確認後、自動的に循環量を減らすか循環ポンプを止める。その結果、ボイラ液面が下がり「液面低」の状態を作る。この時に「液面低」スイッチが正常に作動すれば「液面低」を確認して警報をだし、安全停止動作へ進むので「液面低」スイッチが正常であると容易に確認できる。このような安全点検機能を備えるように構成されることもある。
【００６０】
さらに、上記の２つの機能を備え、運転制御・安全制御用運転盤１１４が液面の「高」と「低」を容易に確認して安全を確認する機能を備えるように構成することがある。
なお、鉛直管１３２の中間部に液面制御用検出スイッチを設けた構成とする場合がある。
【００６１】
図４〜図６は液面検出・制御装置４４の動作状態を示している。液面１３４が鉛直管１３２の中間位置にあるときは、図４に示すように、高位液面検出スイッチ１４０及び低位液面検出スイッチ１４２は開である。液面１３４が高位液面検出スイッチ１４０近傍まで上昇すると、図５に示すように、高位液面検出スイッチ１４０がフロートのマグネット１３６の作用により閉となり、電気信号が制御盤１１４へ制御信号として伝達される。液面１３４が低位液面検出スイッチ１４２近傍まで降下すると、図６に示すように、低位液面検出スイッチ１４２がフロートのマグネット１３６の作用により閉となり、電気信号が制御盤１１４へ制御信号として伝達される。
【００６２】
通常、吸収冷温水機の起動時は内部の圧力バランスが取れていないために、吸収液の循環量は安定せず、高温再生器には多量の吸収液が供給される。そのため、吸収冷温水機を起動すると吸収液の液面は必ず通常の運転中液面より高くなる。液面検出・制御装置が正常に作動することを日常の点検項目に加える手段として、本発明では、この起動時の液面変化を利用する。すなわち、起動時に液面検出・制御装置４４が「高」スイッチの動作を確認しなければ、液面検出・制御装置４４が異常であると運転制御・安全制御用運転盤１１４が判断して、運転に入らず警報を出し、また燃焼運転に入らないようにする制御回路を持っている。このように、起動時に液面検出・制御装置４４のスイッチが「液面高」の作動を確認しなければ、運転に入れないように制御する運転制御・安全制御用運転盤１１４が設けられている。
【００６３】
また、運転制御・安全制御用運転盤１１４に定期点検用のテスト運転モードを設け、定期点検時に液面検出・制御装置４４が「液面低」を検出する運転状態に切り換えることが出来るようにする。テスト運転モードに切り換えてから起動すると、自動運転制御回路により運転を開始しボイラ圧力または蒸気温度が設定値に上がるまで自動運転を行い、設定値に達すると安全のため先に燃焼を止める。燃焼停止確認後、自動的に循環量を減らすか循環ポンプを止める。その結果、ボイラ液面が下がり「液面低」の状態を作る。この時に「液面低」スイッチが正常に作動すれば「液面低」を確認して警報をだし、安全停止動作へ進むので「液面低」スイッチが正常であると容易に確認できる。テスト運転モードでの運転状況は下記の通りである。
（１） テスト運転モードに切り換える。通常は運転停止中の点検時に行う。（運転中に切り換えることも可能）
（２） 通常の起動操作を行う。通常は起動ボタン押すだけである。
（３） 自動運転制御信号により運転を開始し燃焼を開始する。ボイラ圧力または蒸気温度が設定値以上になるまで自動運転を行い、設定値以上に達すると安全のため、まず燃焼停止動作に入る。
（４） 燃焼停止確認後、自動的に吸収液循環量を減らすか吸収液ポンプを停止する。通常、テストモードでない時は吸収液ポンプ異常または吸収液温度異常など他の安全スイッチが先に動作してしまう可能性がある。
（５） ボイラ液面が下がり「液面低」の状態を作る。この時に「液面低」スイッチが正常に作動すれば「液面低」を確認して警報をだし、安全停止動作へ進むので、「液面低」スイッチが正常であると容易にかつ安全に確認できる。安全停止させずに液面低スイッチ動作確認ＯＫの信号を出すようにしてもよい。
（６） 「液面低」を確認して警報をだし、安全停止動作へ進むと、通常の停止動作と同様に自動的に吸収液の稀釈運転に入り稀釈運転時間経過後停止する。
以上のような点検・動作確認は、通常は機械操作に慣れた運転マンが安全状況を確認しながら動作確認を行うことであるが、本発明では、この一連の動作を制御回路に組み込んで「テスト運転モード」とすることで、あまり時間をかけずに、また比較的専門知識のない人でも容易にかつ安全に安全装置の動作確認ができるようにすることを意図している。
この運転で液面が下がっても異常警報を発しない場合は、液面検出・制御装置４４が異常と判断できる。この点検操作により液面検出・制御装置４４の異常による高温再生器１０の空缶運転を防止できる。本発明の吸収冷温水機は、このような安全点検機能を装備することもある。さらに、本発明の吸収冷温水機は、上記２つの機能を持ち、液面の高と低を容易に確認して安全を確認する運転制御・安全制御用運転盤を持つように構成することがある。
【００６４】
本実施形態では、密閉構造のサイクルを対象としているので、フロート１３８による液面検出について説明している。液面を検出する方法として、他の方式、例えば電極式のものを用いることも可能である。
図３〜図６に示す液面検出・制御装置４４においては、筒状の液面検出管（鉛直管１３２）内を強い磁性体（マグネット１３６）を装着したフロート１３８が液面の変動に合わせて上下する。筒状の液面検出管内を強い磁性体を装着したフロート１３８が上昇して上限に達すると、筒の外に設けたスイッチ１４０が磁力により作動（励磁）する。筒状の液面検出管内を強い磁性体を装着したフロート１３８が下降して下限に達すると、筒の外に設けたスイッチ１４２が磁力により作動（励磁）する。
スイッチを作動させる方法として、フロートが上昇した時に上部スイッチを押し上げる方式、下降した時に下部スイッチを押し作動させる方式などがある。また、テコ式フロートスイッチによりテコの力でスイッチを作動させる方式がある。
【００６５】
このように構成された本発明の吸収冷温水機において、蒸発器８９からの冷温水取出管に設けられた冷温水温度センサ１０２から負荷側の温度変化を検出し、その温度変化を運転制御・安全制御運転盤１１４からの制御信号を燃焼装置１８又は燃料流量調節弁（図示略）に導入することにより高温再生器１０に供給される燃料を増減し、燃焼装置１８の燃焼量を増減して高温再生器１０の効率的な運転を行う。
同時に各吸収液ポンプ８２、８５、９３を運転して、水の含有割合の異なる吸収液を安定的に供給・循環して連続運転を行う。すなわち、低温再生器８４から中温再生器８７に液を供給する吸収液ポンプ８５に流入する吸収液の一部を分岐させてバイパス管９５により戻り配管にバイパスさせ、同時に中温再生器８７から高温吸収液ポンプ９３に流入する液の一部を分岐させてバイパス管９６によりバイパスさせ、水・吸収液の供給・循環量を調整して、ポンプ８５、９３に掛かる動力負荷を調整して、省エネルギと安定した連続運転を行う。
【００６６】
また、負荷（冷温水）の温度を冷温水温度センサ１０２で検知し、運転盤１１４を介して燃焼装置１８の燃焼量（加熱量）を増減すると同時に、高温再生器１０内部の蒸気圧が上昇し温度が上昇して、蒸気で加熱される吸収冷凍機の高温再生器出口部の蒸気ドレン温度センサーで検出する温度が上昇した場合には、安全のため、運転盤１１４を介して高温吸収液ポンプ９３の回転数を上げて、液循環量を増加させてその結果蒸気圧を下げ、蒸気ドレン温度センサーで検出するドレン温度が低下すれば、運転盤１１４を介して高温吸収液ポンプ９３の回転数を下げて循環液量を減らして蒸気圧を上げ、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるようにする。ポンプ９３と同時にポンプ８２を回転数制御すると、さらに対応速度を速める効果がある。ポンプ８５は、回転数を変えずに一定速度で運転しても、バイパス管９５で流量が調整されるので、回転数を制御しなくても、問題は生じない。
【００６７】
又は、負荷（冷温水）の温度変化によって燃焼装置１８の燃焼量（加熱量）を増減するのと同時に、高温再生器１０内部の蒸気圧が上昇し温度が上昇して、高温再生器出口部の蒸気配管で検出される、蒸気圧又は温度センサーで検出する温度が上昇した場合には、安全のため高温吸収液ポンプの回転数を上げて、液循環量を増加させて、その結果蒸気圧を下げ、蒸気圧力又は温度が低下すれば、高温吸収液ポンプ９３の回転数を下げて液循環量を減らして蒸気圧を上げ、連続運転に適した温度範囲と圧力範囲で安定した運転が継続できるようにする。ポンプ９３の回転数を上げ下げするのと同時に、ポンプ８２の回転数を上げ下げすると、応答速度が速まり制御性がよくなるという効果がある。
【００６８】
また、高温再生器１０の運転中の液面を液面検出・制御装置４４により検出して、気液分離器２６の液面が上昇した場合には、高温吸収液ポンプ９３の回転数を減らし、液循環量を減らして液面を下げる。一方、液面が降下した場合には、ポンプ９３の回転数を増やして液循環量を多くし液面を上げるように制御して、管板面１２６より上昇することがないようにすることが好ましい。また、高温再生器１０の運転液面が安全運転の下限設定値よりさらに低下した場合には、運転盤１１４を介して、警報を発し燃焼を遮断して安全停止動作に入るようにする。
【００６９】
この場合、高温再生器１０の運転中の液面を液面検出・制御装置４４により検出して、ポンプ９３の回転数を制御する方法として、運転条件、制御信号を受けて予め定められた回転数に段階的に変化させるようにした段階制御式を用いる方法や、運転条件、負荷信号、制御信号を受けて連続的に回転数を変化させるようにした連続制御式を用いる方法等が採用される。
【００７０】
運転中の蒸気ドレン温度、蒸気温度、蒸気圧力又はボイラの運転液面を、蒸気ドレン温度センサー、蒸気温度センサー、蒸気圧力計又は液面検出装置４４で検出して、ポンプの回転数を制御する場合に、制御方式としては、低温吸収液ポンプ８２、中温吸収液ポンプ８５、高温吸収液ポンプ９３の各ポンプを同時にもしくは単独に、又は低温吸収液ポンプ８２と高温吸収液ポンプ９３の２台だけ等の組合せの中から選択した運転方法から、１方式又は複数の方式に切り替えられるようにして、回転数制御をして水を含む吸収液の供給量（循環量）を制御し運転効率を高め、かつ各ポンプが供給量（循環量）不足や揚程（ヘッド）不足を起こさない回転数を確保するように制御される。
【００７１】
また、運転中に、高温再生器１０への水・吸収液を供給する供給装置、例えば高温吸収液ポンプ９３が故障して、供給量が減少した場合には、高温再生器１０内部に保有する水・吸収液量が減少して連続運転に支障が生じるので、警報を発すると同時に燃焼を遮断して、安全停止動作に入るように制御する。
【００７２】
また、運転中に、高温再生器１０への水・吸収液供給量が減少した場合や、高温再生器１０内部に保有する水・吸収液量が減少して各部の温度が安全運転の設定値を越えた場合には、高温再生器１０又は高温再生器１０の吸収液出口部に設けた吸収液温度センサーや空缶防止用の吸収液温度センサーにより運転盤１１４を介して警報を発すると同時に燃焼を遮断して、安全停止動作に入るように制御する。
【００７３】
つぎに、制御フローについて、さらに詳しく説明する。まず、冷水出口（入口）温度Ｔｃ１検出→負荷制御演算→排温水入口温度Ｔｈ１と排温水熱交換器２００入口吸収液温度Ｔｗ１の温度検出、排温水熱交換器出口温水温度Ｔｈ２を検出する。
判定条件▲１▼：Ｔｈ１−Ｔｗ１＞設定値のとき
排温水制御弁１７８の熱回収器側への流量制御弁１７８を全開とし、全量排熱再生器１６８へ流す。制御弁１７８の開度１００％を確認した後、通常の燃焼制御に入る。ついで、負荷制御演算を行い、燃焼操作出力制御及び排温水制御弁１７８の操作出力制御を行う。排温水熱交換器出口温水温度Ｔｈ２が設定値以下の時は、制御弁１７８を閉め排熱再生器１６８へ行く排温水量を絞り、排温水熱交換器入り口吸収液の温度が下がる（排温水により逆に吸収液が冷やされる）のを防止する。
この時、負荷制御演算により、負荷に比べて加熱量が少ない場合は、燃焼制御量を増やして排温水量の不足分を補正する。また、負荷に比べて加熱量が多い場合は、燃焼制御量を減らして冷水出口（入口）温度Ｔｃ１が設定温度で安定するよう制御する。
燃焼熱量をゼロにしても、負荷より加熱量（排温水熱量）が多く、冷水出口（入口）温度Ｔｃ１が低下し設定温度に安定しない時は、吸収液を蒸発器８９に流入させる吸収液流量調節弁１６４を開けて、吸収液を蒸発器８９の冷媒溜まり１６２に流入させ、この蒸発器の冷媒溜まり１６２に溜まった冷媒と流入した吸収液を、蒸発器に設けたオーバーフロー用堰１９０から吸収器８１の吸収液溜まり２０２にこぼす（戻す）。
吸収液流量調節弁１６４は、例えば５秒間開けた後全閉にして冷水温度Ｔｃ１を確認して再度弁１６４を開けるかどうかの判断をする、時間経過と冷水温度Ｔｃ１の変化を確認する機能を制御装置に組み込み、吸収液を必要以上に冷媒溜まりに流入させない制御を含むため、冷水温度が上昇し過ぎることも防止している。そのため、外部熱源機器側への悪影響を軽減するとともに、冷房負荷側への悪影響も軽減することになりエネルギーロスを防止している。
吸収液を冷媒溜まり１６２の冷媒に混入させること、及び冷媒と吸収液を吸収液溜まり２０２にこぼす（戻す）ことにより、冷水出口（入口）温度の下がり過ぎと安全装置の作動を防止し、かつ、排温水を流し続けることにより排温水の戻り温度が安定して外部熱源機器、例えばガスエンジン側への悪影響を軽減する。また、排温水と熱交換する吸収液は、排温水の熱により吸収液温度が下がり過ぎることがなく、運転を継続中に負荷が増加した時の立ちあがりが早く、燃料を燃焼させる追い焚きも低減させることができるので、排熱を有効に利用して省エネルギー効果を上げることができる。
【００７４】
判定条件▲２▼：Ｔｈ１−Ｔｗ１＜設定値のとき、又はＴｈ１−Ｔｗ１＝設定値のとき
排温水制御弁１７８の排熱再生器１６８側への流量制御回路を全閉とし、全量排熱再生器１６８をバイパスさせる。この時、冷房負荷があって加熱源への燃焼操作出力信号がある場合は、通常の燃料燃焼制御を行う。
その他の条件としては、起動時、温水制御可能の場合、燃焼開始前に排温水制御弁１７８を全開とした後、燃焼制御動作が可能となる制御動作とする。停止時には、排温水制御弁１７８は全閉とし、排熱再生器１６８へ排温水を送ることはせず、全量バイパスさせる。
【００７５】
【発明の効果】
本発明は上記のように構成されているので、つぎのような効果を奏する。
（１） 吸収器からの吸収液の一部を冷媒溜まりの冷媒に混入させること、及び冷媒と吸収液を吸収器の吸収液溜まりにこぼす（戻す）ことにより、冷水出口（入口）温度の下がり過ぎと安全装置の作動を防止し、かつ、排温水を流し続けることにより排温水の戻り温度が安定してガスエンジンなどの外部の熱源機器側への悪影響を軽減することができる。
（２） 排温水と熱交換する吸収液は排温水の熱により吸収液温度が下がり過ぎることがなく、運転を継続中に負荷が増加した時の立ち上がりが早く、燃料を燃焼させる追い焚きも低減させることができるので、排熱を有効に利用して省エネルギー効果を上げることができる。
（３） 起動時に液面検出・制御装置が「高」スイッチの作動を確認しなければ、液面検出・制御装置が異常であると運転制御・安全制御用運転盤が判断して、運転に入らず警報を出し、また燃焼運転に入らないようにする制御機能を有する制御回路を備えているので、高温再生器の空缶運転を防止することができる。
（４） 運転で液面が下がっても異常警報を発しない場合は、液面検出・制御装置が異常と判断することができる安全点検機能を備えているので、この点検操作により液面検出・制御装置の異常による高温再生器の空缶運転を防止することができる。
【図面の簡単な説明】
【図１】本発明の実施の第１形態による排熱再生器を有する三重効用形吸収式冷温水機の系統的概略構成図である。
【図２】図１の冷温水機における貫流方式の高温再生器及び液面検出・制御装置を示す概略構成図である。
【図３】図２における液面検出・制御装置の詳細を示す構成図である。
【図４】液面検出・制御装置においてフロートが中間位置にあるときの構成図である。
【図５】液面検出・制御装置においてフロートが上昇したときの構成図である。
【図６】液面検出・制御装置においてフロートが降下したときの構成図である。
【図７】従来の吸収式冷温水機の一例を示す系統的概略構成図である。
【符号の説明】
１０ 高温再生器
１２ 上部管寄せ
１４ 下部管寄せ
１６ 上昇管
１８ 燃焼装置
２０ 燃焼室
２４ 気液混合物導管
２６ 気液分離器
２８ 冷媒蒸気管
３０ 吸収液抜出導管
３６ 吸収液循環導管
４２ 吸収液供給管（水・吸収液供給管）
４３ 液面検出装置
４４ 液面検出・制御装置
４８ 吸収式冷温水機
８１ 吸収器
８２ 低温吸収液ポンプ
８３ 低温熱交換器
８４ 低温再生器
８５ 中温吸収液ポンプ
８６ 中温熱交換器
８７ 中温再生器
８８ 凝縮器
８９ 蒸発器
９０ 冷媒ポンプ
９３ 高温吸収液ポンプ
９４ 高温熱交換器
９５、９６ バイパス管
９７、９８ 冷媒蒸気管
９９ 冷温水ポンプ
１００ 冷却水ポンプ
１０２ 冷温水温度センサー
１１４ 運転制御・安全制御用運転盤
１２６ 管板面
１２８ 上部液出入り管
１３０ 下部液出入り管
１３２ 鉛直管
１３４ 液面
１３６ マグネット
１３８ フロート
１４０ 高位液面検出スイッチ
１４２ 低位液面検出スイッチ
１５１ 第一冷暖切替弁
１６０、１６６ 分岐吸収液管
１６２ 冷媒液溜まり
１６４ 吸収液流量制御弁
１６８ 排熱再生器
１７０ 排温水入口管
１７２ 排温水出口管
１７４、１７６ 温水温度センサー
１７８ 排温水流量制御弁
１８０ 吸収液管
１８２ 吸収液温度センサー
１８４ 第二冷暖切替弁
１８６ 冷媒ドレン熱交換器
１８８ 排ガス熱交換器
１９０ オーバーフロー用堰
１９２ 排熱再生器からの吸収液管
１９４、１９６ 冷媒蒸気管
２００ 排温水熱交換器
２０２ 吸収液溜まり[0001]
BACKGROUND OF THE INVENTION
The present invention has a triple effect absorption chiller / heater having an exhaust heat regenerator, and more specifically, an absorber, a low temperature regenerator, a medium temperature regenerator, a high temperature regenerator, an evaporator, a condenser, a solution heat exchanger, etc. In addition, a triple effect absorption chiller / heater with triple effect is provided with an exhaust heat regenerator that recovers the exhaust heat from the outside, and high-grade heating combustion energy (city gas, LPG, kerosene, heavy oil, etc.) Regenerator built-in system that recovers external exhaust heat that effectively uses exhaust heat supplied from outside by reducing the amount of waste used, and a triple effect absorption chiller / heater with exhaust heat regenerator It is.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a steam double-effect absorption chiller / heater as illustrated in FIG. 7 is known (FIG. 7 shows a case where cold water is obtained as an example). This absorption chiller / heater constitutes a reverse cycle in which an absorbing liquid (for example, an aqueous solution of lithium bromide) flows from the absorber a to the high temperature regenerator e through the low temperature regenerator c. The absorption cycle in this absorption chiller / heater will be described. First, an absorption liquid (a rare absorption liquid) whose concentration has been reduced by absorbing a large amount of refrigerant vapor in the absorber a is transferred from the absorber a to the low-temperature heat exchanger b. After being fed and heated by the low-temperature heat exchanger b, it is fed to the low-temperature regenerator c. The rare absorbent is regenerated at a low temperature in the low temperature regenerator c, and a part of the absorbed refrigerant is released, and the concentration is increased by that amount to become an intermediate concentration absorbent (intermediate absorbent). Next, the intermediate absorbent is fed from the low temperature regenerator c to the high temperature heat exchanger d, heated by the high temperature heat exchanger d, and then fed to the high temperature regenerator e.
[0003]
The intermediate absorption liquid is regenerated at a high temperature in the high temperature regenerator e, and a part of the absorbed refrigerant (for example, water vapor) is released to further increase the concentration to become a high concentration absorption liquid (concentrated absorption liquid). . The concentrated absorbent is returned to the heating side of the high temperature heat exchanger d as a heating source for heating the intermediate absorbent, and further the heating source for heating the rare absorbent on the heating side of the low temperature heat exchanger b. Is returned to the absorber a. The returned concentrated absorbing liquid is sprayed on the heat transfer tube in the absorber a and absorbs the refrigerant vapor again while being cooled by the cooling water to become the rare absorbing liquid.
[0004]
In such a steam double-effect absorption chiller / heater, high-temperature steam (steam) is supplied from the steam boiler f to the high-temperature regenerator e as a heating source. The intermediate absorption liquid is heated and the absorbed refrigerant is released, and the released refrigerant vapor is used by the low temperature regenerator c as a heating source in the low temperature regenerator c and then returned to the condenser g. Condensed. The refrigerant liquid (for example, water) from the condenser g enters the evaporator h, and the condensed refrigerant liquid is sprayed on the heat transfer pipe (water is circulating) of the evaporator h by a refrigerant pump and cooled by latent heat of evaporation. Cold water is obtained.
In addition, a bypass pipe k is provided to connect the absorption liquid pipe i from the low temperature regenerator c and the heating side absorption liquid pipe j between the high temperature heat exchanger d and the low temperature heat exchanger b. A part of the intermediate concentrated absorbent that exits c and is supplied to the high-temperature regenerator e is bypassed to the concentrated absorbent pipe that returns to the absorber a.
[0005]
Normally, when a boiler is operated independently, the steam pressure at the outlet of the boiler, which changes due to external load changes, is detected, and the combustion amount is controlled so that the steam pressure falls within the specified pressure range. ing. During operation, the water level is controlled by controlling the water supply pump so that the water held in the boiler falls within a predetermined water level range.
On the other hand, in the conventional absorption chiller / heater as shown in FIG. 7, the chiller / heater outlet part or the inlet part is detected by detecting the chilled water temperature change at the outlet / inlet part of the chiller / heater that changes due to an external load change. The amount of the heat source to be supplied is controlled so that the temperature of the temperature becomes a predetermined temperature.
[0006]
As for the boiler and the absorption chiller / heater, there are operation systems such as interlocking operation with an interlock, but the normal operation system has independent control. The boiler corresponds to a pressure vessel whose internal pressure exceeds atmospheric pressure, and the absorption chiller / heater corresponds to a vacuum vessel whose internal pressure is below atmospheric pressure. For this reason, it has been conventionally given up that it is impossible to operate and control the two together. However, due to environmental issues, there is a need for the development of cold / hot water machines that save even more energy.
The absorption chiller / heater has, for example, an aqueous lithium bromide solution as a medium that circulates inside and exchanges heat energy. Generally called absorption liquid, it is configured to exhibit a cooling effect by absorbing and evaporating water as a refrigerant.
[0007]
The conventional steam double effect absorption chiller / heater combined with the steam boiler f as shown in FIG. 7 has the following disadvantages.
The steam boiler f itself is large, which leads to an increase in the size of the entire absorption chiller / heater. Moreover, in order to operate the steam boiler f, it is contrary to the demand for energy saving such as supplying water of a system different from the system of the absorption chiller / heater, collecting steam drain after heating, and injecting chemicals. In addition, an additional facility for them is required, which helps increase the size of the device. However, the steam boiler f only contributes to the absorption chiller / heater only by supplying a heating source, and the steam boiler f has a sufficient effect for fuel consumption for combustion in the steam boiler f. It's hard to say that In addition, in terms of laws and regulations, there is annoyance that a predetermined qualified person or an inspection is required as a handling person.
[0008]
In order to integrate the absorption chiller / heater and the boiler for stable operation, the safety device required for the boiler and the chilled water temperature controller required for the absorption chiller / heater, for example, are combined and stably It is necessary to continue safe driving.
When the absorption chiller / heater is integrated with the boiler, steam pressure control is not a very important condition. Rather than that, it is important to stably supply the chilled water temperature required as an absorption chiller / heater. For example, it is important to sufficiently control the heating source so that the chilled water temperature can be supplied stably. become.
On the other hand, in the boiler, even if the absorption chiller / heater changes the chilled water temperature due to load changes, etc., a signal to control the amount of heating source is output, even if the steam pressure fluctuates or the water level of the internal retained water fluctuates rapidly It must be controlled so that it can be operated continuously.
[0009]
Therefore, if the chilled water temperature control of the absorption chiller / heater and the combustion amount control of the boiler are a pair of controls, the absorption liquid installed in the absorption chiller / heater is detected by detecting the steam pressure change and water level change of the boiler separately. Even if the absorption chiller / heater and the boiler are integrated by constructing a control system that controls the circulation rate of the absorption liquid by controlling the number of revolutions of the pump and reducing the influence during operation of the boiler. This enables stable and safe combustion control of the boiler and stable chilled water temperature control as an absorption chiller / heater.
As a control for that purpose, the rotational speed control of the absorbing liquid pump by detecting the steam temperature or pressure, or the rotational speed control of the absorbing liquid pump by detecting the operating liquid level is an important requirement.
However, the safety valve, low water level combustion shut-off device, and water supply device required as a boiler must be equipped at that time.
[0010]
The present applicant has a high-temperature regenerator, a medium-temperature regenerator, a low-temperature regenerator, a condenser, an absorber, an evaporator, a heat exchanger, a solution pump, a refrigerant pump, and a once-through boiler or a once-through boiler. We are developing a triple-effect absorption chiller / heater with an exhaust gas heat exchanger. If the liquid level detector does not operate normally in this triple-effect absorption chiller / heater, the high-temperature regenerator can be operated. May cause serious accidents.
For this purpose, it is important to be able to easily monitor and check that the liquid level detector is operating normally, and the operation control device must be equipped with a function that allows easy monitoring and checking.
Normally, when the absorption chiller / heater is started, the internal pressure is not balanced, so the circulation amount of the absorbent is not stable, and a large amount of absorbent is supplied to the high-temperature regenerator. For this reason, when the absorption chiller / heater is started, the liquid level of the absorbing liquid is always higher than the liquid level during normal operation.
[0011]
Using a once-through type boiler as a high-temperature regenerator and integrating this boiler with an absorption chiller / heater, if an abnormality occurs in these devices on the boiler side, an absorption chiller is also linked in conjunction with the boiler combustion shut-off. An absorption chiller / heater with an energy-saving safety confirmation function capable of continuous operation, which incorporates a control circuit to safely stop, has been developed and has already been filed for a patent.
[0012]
Conventionally, triple effect absorption chiller / heater, absorption chiller / heater using external exhaust heat, etc. have already been invented, but due to the decrease in exhaust heat / hot water temperature after heat recovery of external exhaust heat, There are few examples of the development of absorption chiller / heaters and devices that take into account the effects on the equipment (return side of the waste water), and there is no example of triple effect type.
[0013]
When the use amount of the combustion energy for heating is low and the cooling load is low, the temperature level during the operation cycle of the absorption chiller / heater becomes low. At this time, if external exhaust heat is supplied and used as a heat source for an absorption operation cycle, the temperature of the operation cycle is low, so that the heat recovery amount of the external exhaust heat is increased, and a favorable effect is obtained from the viewpoint of effective use of heat. At this time, the outlet temperature of the exhaust heat hot water (exhaust hot water) decreases corresponding to the temperature decrease of the operation cycle, and the heat recovery amount increases.
An increase in the amount of heat recovered is preferable from the viewpoint of effective use of heat, but a decrease in the temperature of the return exhaust heat hot water may adversely affect other equipment. In particular, when the external heat source system device is a gas engine and the heat of the jacket cooling water of the gas engine is used as an exhaust heat source, the efficiency of the gas engine is reduced.
[0014]
On the other hand, when the cooling load is extremely reduced and it is no longer necessary to recover the exhaust heat, the exhaust water recovery heat exchanger is bypassed to return the hot water to the jacket side of the gas engine. The gas engine is not sufficiently cooled, and problems such as a reduction in efficiency and overheating occur.
For this reason, in the exhaust heat utilization system / equipment combined with the gas engine, the temperature of the heat recovery heat exchanger that recovers exhaust heat and the control device that controls the flow rate of the heat recovery heat exchanger and the temperature of the hot water returned to the gas engine are A control device that controls and controls the amount of exhaust heat recovery is required, and a complicated control device that controls the exhaust heat hot water temperature at the entrance and exit of the exhaust heat recovery heat exchanger is required.
The air conditioning load in the absorption chiller / heater, the power generation load of external heat source system equipment such as a gas engine, the exhaust heat / hot water temperature in the chiller / heater, and the fuel reduction rate in the chiller / heater can be summarized roughly. As shown in Table 1.
[0015]
[Table 1]

[0016]
As shown in Table 1, when the balance between the cooling load and the power generation load is changed, the operating conditions are changed, and in particular, the temperature condition of the absorbing liquid circulating inside the absorption chiller / heater side is changed. Therefore, it can be seen that it is difficult to perform efficient heat recovery and energy-saving operation of the absorption chiller / heater by controlling only a part of the temperature conditions.
[0017]
Conventionally, as a double-effect absorption chiller / heater, the control is performed by detecting the chilled water outlet temperature or the chilled water inlet temperature to control the heating amount, and the inlet temperature when the exhaust hot water enters the exhaust heat recovery device. A control system has been invented for controlling the heat recovery amount of the absorption chiller / heater by controlling the temperature (for example, see Patent Document 1 and Patent Document 2). However, in addition to load control and exhaust heat recovery control of the absorption chiller / heater, a control circuit (method) that considers the effect on the equipment side (for example, gas engine) that detects the return temperature and generates exhaust heat Has not been proposed.
[0018]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-83228 (2nd page, FIG. 2)
[Patent Document 2]
JP 2000-65436 A (second page, FIG. 1)
[0019]
[Problems to be solved by the invention]
In the control of an absorption chiller / heater that recovers heat using external waste heat, normally, the control of the amount of exhaust heat supplied from the outside by detecting the chilled / hot water outlet temperature of the absorption chiller / heater, and the chiller / heater Control of the amount of combustion of the own combustion equipment. In other words, when the cooling load is high, all exhaust heat is recovered, and the amount of combustion is increased and decreased to control the chilled water outlet temperature to be constant. Shut off the fuel supply to the plant and perform air conditioning operation using only the exhaust heat as the heat source.
From the standpoint of the absorption chiller / heater unit, there is no problem with the control corresponding to the increase / decrease of the normal cooling / heating load. However, the influence of the load on the facility side that generates exhaust heat and supplies this exhaust heat to the absorption chiller / heater, that is, the exhaust heat source such as a gas engine that is operating in combination with the generator, is not considered at the same time. However, it cannot be said to be optimal control, and driving tends to be unstable.
However, in consideration of these points, a triple-effect absorption chiller / heater and a control device therefor have not been proposed which have further improved efficiency and energy saving than the double-effect absorption chiller / heater.
[0020]
The present invention has been made in view of the above points, and an object of the present invention is to effectively recover external exhaust heat in a triple effect absorption chiller / heater incorporating an external exhaust heat regenerator, and It is designed to reduce the impact on other heat source equipment (gas engine etc. in the case of cogeneration system) due to the temperature drop of exhaust heat water. In addition to the conventional heat recovery method, exhaust heat recovery Triple effect with a waste heat regenerator designed to increase the controllability and recovery efficiency at the time, and also to increase the efficiency of the equipment on the return side of the waste water (such as a gas engine that is also a heat source that generates waste water) It is in providing a shape absorption type cold / hot water machine.
[0021]
[Means for Solving the Problems]
In order to achieve the above object, a triple effect absorption chiller / heater having an exhaust heat regenerator according to the present invention uses a once-through boiler or a boiler having a structure equivalent to a once-through boiler as a high-temperature regenerator. A triple-effect absorption chiller / heater unit that integrates a regenerator and a double-effect absorption chiller / heater, with a high-temperature regenerator, medium-temperature regenerator, low-temperature regenerator, condenser, absorber, evaporator, In a reverse-flow triple effect absorption chiller / heater having at least a heat exchanger, a solution pump and a refrigerant pump, and leading the absorption liquid of the absorber from the low temperature regenerator to the medium temperature regenerator, and then to the high temperature regenerator, An exhaust heat regenerator that recovers exhaust heat from the outside and effectively uses it as a heating source to heat the absorption liquid and heat and evaporate the refrigerant absorbed in the absorption liquid to increase the concentration of the absorption liquid. Installed in front of the regenerator and absorbs liquid with a low temperature regenerator Reduce the heat exchange rate of the low-temperature regenerator by increasing or decreasing the amount of exhaust heat recovered from the outside by increasing or decreasing the ratio of the heating heat amount that raises the concentration of the absorption liquid by heating and is generated in the high-temperature regenerator and medium-temperature regenerator Reduce the amount of fuel used for heating in the high-temperature regenerator and save energy by reducing the amount of refrigerant vapor generated as a heating source for the low-temperature regenerator by heating and concentrating the absorption liquid. It is characterized by trying to plan.
[0022]
In this triple effect type absorption chiller / heater, the ratio of the heat of heating that increases the concentration of the absorbent by heating the absorbent with a low-temperature regenerator is reduced by 15 to 40% by increasing or decreasing the amount of exhaust heat recovered from the outside. It is preferable to make it.
Further, compared to a triple effect absorption chiller / heater when no exhaust heat regenerator is provided, by providing the exhaust heat regenerator as in the present invention, the amount of fuel consumed for heating in the high temperature regenerator is 15 to 15%. The energy is reduced by 30% to save energy.
In addition, an exhaust hot water control valve, an exhaust hot water conduit, and an exhaust hot water controller are provided for recovering external exhaust heat and using it as a heat source for the exhaust heat regenerator.
[0023]
Also, when the temperature of the exhaust water at the inlet of the exhaust heat regenerator is higher than the temperature of the absorption liquid heated in the exhaust heat regenerator by a predetermined temperature (for example, plus 3 ° C), the exhaust heat water is recovered by controlling the exhaust water control valve. It is configured to flow into the vessel and heat the absorption liquid.
Further, the temperature of the exhaust water is returned so that it does not adversely affect the operating conditions and efficiency of the heat source system equipment (for example, a gas engine) that is a heat source for generating external exhaust heat (for example, 60 ° C. or more). The waste water temperature is controlled using a waste water control valve so that the waste water flows into the waste heat regenerator and heats the absorption liquid. In addition, a waste heat water three-way control valve that controls the flow rate of waste heat hot water is provided at the exhaust heat regenerator inlet, and a waste heat water three-way control valve that controls the flow rate of waste heat hot water is provided at the exhaust heat regenerator outlet. It is preferable to do.
[0024]
The absorption pump outlet of the absorber and the evaporator are connected via an absorption liquid distribution pipe having a flow control valve, and the temperature sensor provided in the cold water outlet pipe or the cold water inlet pipe of the evaporator and the flow control valve are connected. Via the control device (control panel), it is possible to control the amount of absorbed liquid flowing into the evaporator according to the temperature detected by the temperature sensor, and further, the refrigerant accumulated in the evaporator refrigerant pool and the absorbed liquid flowing into the evaporator are An overflow weir or an overflow pipe provided in the pipe is allowed to flow down or return to the absorber liquid reservoir.
[0025]
Exhaust heat recovery amount during partial heat operation that does not require additional combustion operation with a high-temperature regenerator combustion device while exhaust heat is supplied to the exhaust heat regenerator and exhaust heat is recovered The absorption pump operation is controlled to increase the circulation rate of the absorption liquid so as to increase the amount of absorption liquid as much as possible. When the load increases and the reheating combustion operation becomes necessary, it is efficiently performed according to the load. The discharge amount of the absorption liquid pump is controlled so as to be the absorption liquid circulation amount to be operated.
Also, during the partial load operation in which the exhaust heat is passed through the exhaust heat regenerator and the exhaust heat is recovered to reduce the heat of combustion and the combustion device of the high temperature regenerator is used for the partial load operation, the high temperature regeneration is performed due to load fluctuations, etc. In order to prevent the liquid level in the chamber from fluctuating and causing a safety stop due to empty can operation or low liquid level, the discharge rate of the absorption pump is controlled to ensure the amount of absorption liquid circulating to the high-temperature regenerator, It is configured to enable continuous and stable operation.
[0026]
The exhaust heat regenerator is preferably configured to use a pool boiling type shell-and-tube heat exchanger in which a heated fluid (exhaust hot water) flows inside the tube and a rare absorbing liquid flows outside the tube.
In this case, the rare absorption liquid outlet of the pool boiling type shell-and-tube heat exchanger is provided near the uppermost stage of the heat transfer tube group constituting the shell-and-tube heat exchanger, The arrangement of the heat transfer tubes at the uppermost stage and the lower stage of the heat transfer pipe group is set so as not to inhibit the outflow of the surfactant added to the absorbent from the rare absorbent outlet.
Moreover, it is preferable that the arrangement | positioning of the heat exchanger tube of the uppermost stage of an exhaust heat regenerator and the stage below it is made into the grid | lattice arrangement.
[0027]
Furthermore, the refrigerant vapor line from the exhaust heat regenerator to the low-temperature regenerator is provided with a branch line connected to the heating side of the evaporator, and a cooling / heating switching means for switching between cooling and heating is provided in the branch line. The cooling / heating switching means is switched to heating, and the refrigerant vapor from the exhaust heat regenerator is guided to the evaporator to heat the hot water flowing in the heat transfer tube in the evaporator.
[0028]
As described above, in the triple-effect absorption chiller / heater that effectively recovers the exhaust heat supplied from the outside to save energy, the equipment that effectively recovers this external exhaust heat and generates the exhaust heat In addition to the conventional load control that controls the amount of heating by detecting the chilled water outlet (inlet) temperature of the absorption chiller / heater to enable ideal operation that eliminates the influence on the side, external heat exhaust can be performed To recover as much as possible and eliminate the effect on the facility side that generates waste heat, and to prevent the heat recovery amount control circuit to control the return temperature of waste heat, and to prevent the cold water outlet (inlet) temperature from dropping too low Are provided with an absorption liquid pipe connected so that the absorption liquid flows into the evaporator (refrigerant reservoir), and an absorption liquid control valve provided in the middle of the pipe.
[0029]
In these triple-effect absorption chiller / heater units, the combustion pressure (heating amount) of the combustion device is increased or decreased due to the temperature change of the load (cold / warm water), and at the same time, the steam pressure inside the boiler rises and the temperature rises. When the temperature detected by the steam drain temperature sensor at the outlet of the intermediate temperature regenerator of the absorption chiller heated by steam rises, increase the number of circulating liquids by increasing the rotational speed of the absorption liquid supply pump for safety. As a result, the vapor pressure is lowered, and if the drain temperature falls, the rotation speed of the absorption liquid supply pump is lowered to reduce the liquid circulation amount to raise the vapor pressure, and the temperature range and pressure range suitable for continuous operation. It is configured to have a control function that allows stable operation to continue.
[0030]
In addition, the combustion pressure (heating amount) of the combustion device is increased or decreased by the temperature change of the load (cold hot / cold water), and at the same time, the steam pressure inside the boiler rises and the temperature rises, which is detected by the steam piping at the boiler outlet. When the temperature detected by the steam pressure or temperature sensor rises, for the sake of safety, increase the number of revolutions of the absorption liquid supply pump, increase the amount of liquid circulation, and consequently reduce the steam pressure. Alternatively, if the temperature drops, the rotation speed of the absorption liquid supply pump is reduced to reduce the amount of liquid circulation and increase the vapor pressure, so that stable operation can be continued in the temperature range and pressure range suitable for continuous operation. Configure to have functionality.
[0031]
In these hot and cold water machines, the liquid level during operation of the boiler is detected by the liquid level detection device, and if the liquid level rises, the number of revolutions of the pump is reduced and the liquid circulation rate is reduced to lower the liquid level. If the liquid level drops, control the pump to increase the liquid circulation rate and increase the liquid level by increasing the number of revolutions of the pump, and when the operating liquid level further falls below the lower limit set value for safe operation. Is configured to have a safety control function that issues an alarm, cuts off combustion, and enters a safe stop operation.
Also, when detecting the steam drain temperature, steam temperature, steam pressure or operating liquid level of the boiler during operation to control the rotation speed of the pump, the control is low temperature absorption liquid pump, high temperature absorption liquid pump, water / absorption Switch one method or multiple methods from the operation method selected from the combination of each pump of the liquid supply pump simultaneously or independently, or only two units of the low-temperature absorption liquid pump and the water / absorption liquid supply pump As a result, the rotational speed is controlled to control the supply amount (circulation amount) of the absorption liquid containing water to increase the operation efficiency, and each pump causes a shortage of supply amount (circulation amount) and a head. It is configured to control so as to ensure no rotation speed.
[0032]
In these chiller / heaters, when the supply device that supplies water / absorbing liquid to the boiler fails during operation and the supply amount decreases, the amount of water / absorbing liquid held in the boiler decreases. As a result, continuous operation will be hindered. Therefore, a safety control function is set so that a warning is issued and combustion is interrupted at the same time so that a safe stop operation is started.
In addition, when the water / absorbing liquid supply to the boiler decreases during operation, or when the water / absorbing liquid volume held in the boiler decreases and the temperature of each part exceeds the set value for safe operation In addition, an alarm is generated by an absorption liquid temperature sensor provided in the boiler or an empty can prevention absorption liquid temperature sensor, and at the same time, combustion is cut off and a safety control function is set so as to enter a safe stop operation.
[0033]
Further, the steam separates the vapor that has been heated and evaporated, the absorption liquid that has not evaporated, and the absorption liquid that contains water recirculated to the boiler, and distributes the vapor and the absorption liquid so that continuous operation is possible. It is set as the structure provided with a separator.
[0034]
The absorption chiller / heater control method described above is an absorption chiller / heater unit that integrates a boiler and an absorption chiller, detects temperature changes on the load side from the chiller / warm water temperature sensor, and controls the temperature changes. Increase or decrease the fuel (gas, oil, waste heat) supplied to the boiler by the control signal from the safety control operation panel (operating panel), increase or decrease the combustion amount of the combustion device, and operate the boiler efficiently, At the same time, each absorption liquid pump of the absorption chiller is operated to stably supply (circulate) absorption liquids with different water content ratios, enabling continuous operation, and supplying liquid from the low-temperature regenerator to the upper regenerator. A part of the absorption liquid flowing into the absorption liquid pump is branched and bypassed to the return pipe, and at the same time, a part of the liquid flowing from the intermediate temperature regenerator to the water / absorption liquid supply pump is branched and bypassed to the return pipe. Supply amount of water / absorption liquid (absorption liquid) (circulation amount) Adjusted to, by adjusting the power load on the pump is intended to perform a stable continuous operation and energy saving.
[0035]
In this method, the absorption refrigeration is heated by steam when the combustion pressure (heating amount) of the combustion apparatus is increased or decreased by the temperature change of the load (cold hot / cold water) and at the same time the steam pressure inside the boiler rises and the temperature rises. If the temperature detected by the steam drain temperature sensor at the outlet of the high-temperature regenerator of the machine rises, for the sake of safety, increase the rotation speed of the absorption liquid supply pump, increase the amount of liquid circulation, and lower the vapor pressure as a result. If the drain temperature drops, the rotation speed of the absorbing liquid supply pump is lowered to reduce the amount of liquid circulation and increase the vapor pressure, so that control is performed so that stable operation can be continued in a temperature range and pressure range suitable for continuous operation. Configure.
[0036]
In addition, the combustion pressure (heating amount) of the combustion device is increased or decreased by the temperature change of the load (cold hot / cold water), and at the same time, the steam pressure inside the boiler rises and the temperature rises, which is detected by the steam piping at the boiler outlet. If the temperature detected by the vapor pressure or temperature sensor rises, for the sake of safety, increase the number of revolutions of the absorption liquid supply pump, increase the amount of liquid circulation, and consequently reduce the vapor pressure. If the pressure drops, the rotational speed of the absorption liquid supply pump is lowered to reduce the liquid circulation rate to increase the vapor pressure, and control is performed so that stable operation can be continued in a temperature range and pressure range suitable for continuous operation. .
[0037]
In these methods, the liquid level during operation of the boiler is detected by the liquid level detection device, and when the liquid level rises, the number of rotations of the pump is reduced, the liquid circulation amount is reduced, the liquid level is lowered, and the liquid level is reduced. If the operating liquid level falls further below the lower limit set value for safe operation, an alarm is issued. Control to shut off combustion and enter safe stop operation.
[0038]
In this method, the liquid level during the operation of the boiler is detected by the liquid level detection device, and the rotational speed of the pump is controlled in response to the operating conditions and control signal, and gradually changes to a predetermined rotational speed. As a method of using a stepped control equation, or a method of detecting the liquid level during operation of the boiler by a liquid level detection device and controlling the rotation speed of the pump, operating conditions, load signal, control signal In response to this, a method of using a continuous control formula in which the rotation speed is continuously changed is used.
[0039]
In these methods, when detecting the steam drain temperature, the steam temperature, the steam pressure or the operating liquid level of the boiler during operation and controlling the rotation speed of the pump, the control is performed by a low-temperature absorbent pump, a high-temperature absorbent pump, One or a plurality of operation methods selected from a combination of each of the water / absorbing liquid supply pumps simultaneously or independently, or a combination of only two of the low-temperature absorbing liquid pump and the water / absorbing liquid supply pump The system can be switched and the number of revolutions is controlled to control the supply amount (circulation amount) of the absorbing liquid containing water to improve the operation efficiency, and each pump causes shortage of supply amount (circulation amount) and head. Control to ensure no rotation speed.
[0040]
In these methods, when the supply device for supplying water / absorbing liquid to the boiler fails during operation and the supply amount decreases, the amount of water / absorbing liquid held in the boiler decreases continuously. Since this will hinder the operation, control is performed so that a safety stop operation is started by issuing an alarm and simultaneously shutting off the combustion.
In addition, when the water / absorbing liquid supply to the boiler decreases during operation, or when the water / absorbing liquid volume held in the boiler decreases and the temperature of each part exceeds the set value for safe operation Then, an alarm is issued by an absorption liquid temperature sensor or an empty can prevention absorption liquid temperature sensor provided in the boiler, and at the same time, combustion is shut off and control is performed so as to enter a safe stop operation.
[0041]
In these methods, steam and absorption liquid are distributed so that the boiler can be operated continuously by separating the vapor that has been heated and evaporated, the absorption liquid that has not evaporated, and the absorption liquid that contains water recirculated to the boiler. A boiler having a gas-liquid separator is configured to be used.
[0042]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications.
FIG. 1 shows an absorption chiller / heater according to a first embodiment of the present invention, FIG. 2 shows the periphery of a liquid level detection / control device, and FIG. 3 shows details of the liquid level detection / control device. As the high-temperature regenerator, a once-through boiler or a boiler having the same function and structure is used, but in this embodiment, a case of using a once-through boiler type as the high-temperature regenerator is shown. Reference numeral 10 denotes a high-temperature regenerator having a once-through boiler structure, which has an annular upper header (upper header) 12 and a lower header (lower header) 14 at the upper and lower portions, and a vertical direction between these headers 12 and 14. Are arranged in a substantially cylindrical shape, have a combustion device 18 such as a burner at the upper center, introduce a rare absorbent into the lower header 14, concentrate by heating, and from the upper header 12. It is comprised so that a gas-liquid mixture can be taken out. Reference numeral 20 denotes a combustion chamber.
[0043]
A gas-liquid separator 26 is connected to the high-temperature regenerator 10 through a gas-liquid mixture conduit 24. A refrigerant vapor pipe 28 is connected to the upper part of the gas-liquid separator 26, and an absorbing liquid extraction conduit 30 is connected to the lower part of the gas-liquid separator 26.
The lower part of the gas-liquid separator 26 and the lower header 14 of the high-temperature regenerator 10 are connected via an absorbing liquid circulation conduit 36. An absorbent supply pipe 42 is connected to the absorbent circulation pipe 36 or the lower header 14. Reference numeral 43 denotes a liquid level detection device for the gas-liquid separator 26. Further, an absorption liquid temperature sensor (not shown) for preventing empty cans is provided on the lower surface or side surface of the lower header 14.
[0044]
In this embodiment, the absorber 81, the low-temperature absorption liquid pump 82, the low-temperature heat exchanger 83, the low-temperature regenerator 84, the intermediate absorption liquid pump 85, the intermediate temperature heat exchanger 86, the intermediate temperature regenerator 87, the condenser 88, and the evaporator 89. , A refrigerant cycle 90, an absorption liquid pipe connecting these devices, a reverse cycle double-effect absorption refrigerator having a refrigerant pipe and the like as components, a high-temperature regenerator 10 having a once-through boiler structure, a solution supply A high-temperature absorbing liquid pump 93, a high-temperature heat exchanger 94, and the like as means are combined and integrated. 48 is an absorption-type cold / hot water machine. In FIG. 1, an arrow attached to the solid line indicates the flow direction of the absorption liquid, the refrigerant liquid, or water, and an arrow attached to the broken line indicates the flow direction of the refrigerant vapor or the mixture of the refrigerant vapor and the condensed refrigerant (refrigerant drain). Indicates.
[0045]
Reference numeral 95 denotes a first bypass pipe for bypassing a part of the absorption liquid from the low temperature regenerator 84 to the concentrated absorption liquid pipe from the intermediate temperature heat exchanger 86. Reference numeral 96 denotes a second bypass pipe for bypassing a part of the absorbent from the intermediate temperature regenerator 87 to the return concentrated absorbent pipe from the high temperature heat exchanger 94. Reference numeral 99 is a cold / hot water pump, 100 is a cooling water pump, and 151 is a first cooling / heating switching valve. It is possible to install another concentrator between the intermediate temperature regenerator 87 and the high temperature regenerator 10.
[0046]
Further, the outlet pipe of the low-temperature absorption liquid pump 82 branches, and one branch absorption liquid pipe 160 is connected to the refrigerant liquid reservoir 162 of the evaporator 89, and an absorption liquid flow rate control valve 164 is provided in the branch absorption liquid pipe 160. The valve 164 is connected to the operation control / safety control operation panel 114.
[0047]
The other branched absorption liquid pipe 166 from the low temperature absorption liquid pump 82 is connected to the low temperature heat exchanger 83, and the absorption liquid is heated by the low temperature heat exchanger 83 and then introduced into the exhaust heat regenerator 168. The heat regenerator 168 is supplied with exhaust hot water generated by exhaust heat from an external heat source device such as a gas engine, a gas turbine, or an incinerator as a heat source.
[0048]
And the warm water inlet pipe 170 and the drain warm water outlet pipe 172 are provided with warm water temperature sensors 174 and 176, respectively, and these sensors 174 and 176 are connected to the operation panel 114. Further, a waste water temperature flow control valve 178 which is, for example, a three-way control valve is provided in the waste water temperature inlet pipe 170 and / or the waste water temperature outlet pipe 172, and the control valve 178 and the operation panel 114 are connected to each other. Further, an absorption liquid temperature sensor 182 is provided in the absorption liquid pipe 180 at the inlet of the exhaust heat regenerator 168, and the sensor 182 and the operation panel 114 are connected to each other. 184 is a second cooling / heating switching valve, 186 is a refrigerant drain heat exchanger, and 188 is an exhaust gas heat exchanger. Reference numeral 190 denotes an overflow weir provided in the refrigerant liquid reservoir 162 of the evaporator 89. It is also possible to use an overflow pipe instead of the weir.
[0049]
Next, in the absorption chiller / heater configured as described above, the absorption liquid circulation cycle will be described in order. First, a rare absorbing liquid whose concentration has been reduced by absorbing a large amount of refrigerant vapor in the absorber 81 is branched from the outlet pipe of the low-temperature absorbing liquid pump 82, and one of the absorbing liquid is transferred from the absorber 81 to the low-temperature heat exchanger 83. After being fed and heated by this low-temperature heat exchanger 83, it is introduced into the exhaust heat regenerator 168, and one is connected to the refrigerant liquid reservoir 162 of the evaporator 89. The rare absorption supplied to the exhaust heat regenerator 168 is regenerated by being heated by the exhaust hot water, and a part of the absorbed refrigerant is released to increase the concentration accordingly, and the low temperature regeneration is performed via the absorption liquid pipe 192. To the device 84. The refrigerant vapor from the exhaust heat regenerator 168 contains an absorption liquid and is sent to the low temperature regenerator 84 and the evaporator 89 via the refrigerant vapor pipes 194 and 196. The refrigerant vapor pipe 196 to the evaporator is provided with a second cooling / heating switching valve 184.
[0050]
Most of the intermediate concentrated absorbent regenerated at low temperature in the low temperature regenerator 84 is fed from the low temperature regenerator 84 to the intermediate temperature heat exchanger 86 by the intermediate temperature absorption liquid pump 85 and heated by the intermediate temperature heat exchanger 86. It is fed to the medium temperature regenerator 87. The intermediate concentrated absorbent is regenerated in the intermediate temperature regenerator 87, and a part of the absorbed refrigerant is released, and the concentration is further increased to become a high concentration concentrated absorbent.
The remainder of the intermediate concentrated absorbent from the low-temperature regenerator 84 is bypass-supplied via the bypass pipe 95 to the concentrated absorbent pipe that returns to the absorber 81.
[0051]
Part or all of the concentrated absorbent from the intermediate temperature regenerator 87 is fed to the high temperature heat exchanger 94 by the high temperature absorbent pump 93, where it is heated by exchanging heat with the concentrated absorbent from the high temperature regenerator 10. Then, it is supplied to the high temperature regenerator 10. The remaining portion of the concentrated absorption liquid from the intermediate temperature regenerator 87 (which may be zero) joins the absorption pipe on the heating side from the high temperature heat exchanger 94 via the second bypass pipe 96.
[0052]
In the high temperature regenerator 10, the concentrated absorbent heated and concentrated by the combustion heat of the fuel such as gas fuel is introduced to the heating side of the high temperature heat exchanger 94 and the concentrated absorbent from the intermediate temperature regenerator 87 is heated. It is introduced into the heating side of the intermediate temperature heat exchanger 86. The remaining portion of the concentrated absorption liquid from the intermediate temperature regenerator 87 (which may be zero) joins the absorption pipe on the heating side from the high temperature heat exchanger 94 via the second bypass pipe 96.
The refrigerant vapor from the high-temperature regenerator 10 is introduced into the intermediate-temperature regenerator 87 through the refrigerant vapor pipe 28, and the refrigerant drain is introduced into the low-temperature regenerator 84 after the absorption liquid is heated and concentrated here.
[0053]
The refrigerant vapor from the intermediate temperature regenerator 87 passes through the refrigerant vapor pipe 97 and is sent to the low temperature regenerator 84 together with the refrigerant drain from the intermediate temperature regenerator 87, where the absorbent is heated and concentrated.
The refrigerant vapor from the low-temperature regenerator 84 passes through the refrigerant vapor pipe 98 to the condenser, and the refrigerant drain from the low-temperature regenerator 84 is a refrigerant drain heat exchanger 186. After the part is heated, it is introduced into the condenser 88. Note that the combustion exhaust gas from the high-temperature regenerator 10 is introduced into an exhaust gas heat exchanger (not shown), the absorption liquid or the refrigerant is heated, and the retained heat of the exhaust gas is recovered.
[0054]
Further, a cold / hot water temperature sensor 102 is provided in the cold / hot water extraction pipe, a vapor drain temperature sensor (not shown) is provided in the vapor drain pipe from the intermediate temperature regenerator 87, and an absorbing liquid extraction conduit from the gas-liquid separator 26. An absorption liquid temperature sensor (not shown) is provided at 30, and a vapor temperature sensor (not shown) and a pressure gauge (pressure sensor (not shown)) are provided at the refrigerant vapor pipe 28. The steam drain temperature sensor, the steam temperature sensor, and the steam pressure sensor are not provided at the same time, and any one of them may be provided. Two or more may be provided. Further, as described above, an absorption liquid temperature sensor (not shown) for preventing empty cans is provided on the lower surface of the lower header 14 of the high temperature regenerator 10.
[0055]
Further, as described above, the operation control / safety control operation panel 114 is provided. The operation panel 114, the absorption liquid flow rate control valve 164, the hot water temperature sensors 174 and 176, the exhaust hot water flow rate control valve 178, the absorption liquid temperature. Sensor 182, cold / hot water temperature sensor 102, vapor drain temperature sensor, gas-liquid separator liquid level detection device 43, combustion device 18, absorption liquid temperature sensor at the gas-liquid separator outlet, absorption liquid temperature sensor for preventing empty cans, The low-temperature absorption liquid pump 82, the medium-temperature absorption liquid pump 85, the high-temperature absorption liquid pump 93, the vapor temperature sensor of the refrigerant vapor pipe 28, the pressure gauge (pressure sensor), and the exhaust gas temperature sensor are interlocked and connected. The flow rate and the like can be controlled. Note that the steam drain temperature sensor, the steam temperature sensor, and the steam pressure sensor are not provided at the same time, but any one of them is provided. Two or more may be provided.
[0056]
Further, as described above, an exhaust gas heat exchanger is provided in the exhaust gas passage of the high-temperature regenerator 10, and absorption from an absorption liquid pump that supplies liquid to the exhaust gas heat exchanger, for example, from the low-temperature regenerator to the intermediate-temperature regenerator. A part of the liquid is introduced and heated with exhaust gas. It is also possible to adopt a configuration in which combustion air is introduced instead of the absorbing liquid and the exhaust gas is heated. An exhaust gas temperature sensor (not shown) is provided in the exhaust gas passage at the outlet of the exhaust gas heat exchanger.
The exhaust gas temperature sensor and the operation control / safety control operation panel 114 are connected to each other via a control line, and the gas-liquid separator 26 connected to the gas-liquid mixture conduit 24 of the high-temperature regenerator 10 is connected to the high-temperature regenerator 10. A liquid level detecting / controlling device 44 for controlling the liquid level is provided.
[0057]
As shown in FIGS. 2 and 3, the liquid level detection / control device 44 includes a vertical pipe 132 (for example, a metal pipe) connected to the gas-liquid separator 26 via an upper liquid inlet / outlet pipe 128 and a lower liquid inlet / outlet pipe 130. The float 138 containing the magnet 136 is floated on the inner liquid level 134, and the high level liquid level detection switch 140 and the low level liquid level detection switch 142 are attached to the outer surface of the vertical pipe 132. The high level liquid level detection switch 140 is regenerated at high temperature. The switch 140 and 142 are operated by the magnetic force of the magnet 136 built in the float 138 and detect the change in the liquid level as an electric signal. The signal is transmitted as a control signal for informing the operation control / safety control operation panel 114 of the liquid level.
[0058]
Further, if the operation control / safety control operation panel 114 does not confirm the operation of the “high” switch at the time of activation, the operation control is performed if the liquid level detection / control device 44 is abnormal. The control panel 114 for safety control judges and issues a warning without entering the operation, and a control circuit for controlling so as not to enter the combustion operation is provided.
[0059]
In addition, when the operation control / safety control operation panel 114 is provided with a test operation mode for inspection and started after switching to the test operation mode, the operation is started by the automatic operation control circuit, and the boiler pressure or the steam temperature is set to the set value. The automatic operation is continued until it reaches, and when it reaches the set value, the combustion is stopped first for safety. After confirming that combustion has stopped, automatically reduce the circulation volume or stop the circulation pump. As a result, the boiler liquid level falls, creating a “liquid level low” state. At this time, if the “liquid level low” switch operates normally, the “liquid level low” switch is confirmed, an alarm is given, an alarm is issued, and the operation proceeds to a safe stop operation. Therefore, it can be easily confirmed that the “liquid level low” switch is normal. It may be configured to have such a safety check function.
[0060]
Furthermore, the above-mentioned two functions may be provided, and the operation control / safety control operation panel 114 may be configured to have a function of easily checking the liquid level “high” and “low” to confirm safety. .
In some cases, a liquid level control detection switch is provided in the middle of the vertical pipe 132.
[0061]
4 to 6 show the operating state of the liquid level detection / control device 44. FIG. When the liquid level 134 is in the middle position of the vertical pipe 132, as shown in FIG. 4, the high level liquid level detection switch 140 and the low level liquid level detection switch 142 are open. When the liquid level 134 rises to the vicinity of the high liquid level detection switch 140, as shown in FIG. 5, the high liquid level detection switch 140 is closed by the action of the float magnet 136, and an electric signal is transmitted to the control panel 114 as a control signal. Is done. When the liquid level 134 is lowered to the vicinity of the lower liquid level detection switch 142, as shown in FIG. 6, the lower liquid level detection switch 142 is closed by the action of the float magnet 136, and an electric signal is transmitted to the control panel 114 as a control signal. Is done.
[0062]
Normally, when the absorption chiller / heater is started, the internal pressure is not balanced, so the circulation amount of the absorption liquid is not stable, and a large amount of absorption liquid is supplied to the high-temperature regenerator. For this reason, when the absorption chiller / heater is started, the liquid level of the absorption liquid is always higher than the liquid level during normal operation. In the present invention, the change in the liquid level at the time of activation is used as a means for adding that the liquid level detection / control device operates normally to the daily inspection item. That is, if the liquid level detection / control device 44 does not confirm the operation of the “high” switch at startup, the operation control / safety control operation panel 114 determines that the liquid level detection / control device 44 is abnormal, It has a control circuit that gives an alarm without entering operation and prevents it from entering combustion operation. As described above, the operation control / safety control operation panel 114 is provided to control the liquid level detection / control device 44 so that it does not enter the operation unless the switch of the liquid level detection / control device 44 confirms the operation of the “liquid level”. Yes.
[0063]
In addition, a test operation mode for periodic inspection is provided in the operation control / safety control operation panel 114 so that the liquid level detection / control device 44 can be switched to an operation state for detecting “low liquid level” during the periodic inspection. To do. When starting after switching to the test operation mode, the operation is started by the automatic operation control circuit, and the automatic operation is performed until the boiler pressure or the steam temperature rises to the set value. When the set value is reached, the combustion is stopped first for safety. After confirming that combustion has stopped, automatically reduce the circulation volume or stop the circulation pump. As a result, the boiler liquid level falls, creating a “liquid level low” state. At this time, if the “liquid level low” switch operates normally, the “liquid level low” switch is confirmed, an alarm is given, an alarm is issued, and the operation proceeds to a safe stop operation. Therefore, it can be easily confirmed that the “liquid level low” switch is normal. The operation status in the test operation mode is as follows.
(1) Switch to test operation mode. Usually, it is performed at the time of inspection while operation is stopped. (It is possible to switch during operation)
(2) Perform normal startup operations. Usually just press the start button.
(3) The operation is started by the automatic operation control signal and combustion is started. Automatic operation is carried out until the boiler pressure or steam temperature exceeds the set value, and when it reaches the set value or higher, the combustion stop operation is first started for safety.
(4) After confirming that combustion has stopped, automatically reduce the amount of absorbent circulating or stop the absorbent pump. Usually, when not in the test mode, there is a possibility that other safety switches such as an absorption liquid pump abnormality or an absorption liquid temperature abnormality operate first.
(5) The boiler liquid level drops and creates a “liquid level low” state. At this time, if the “Liquid level low” switch operates normally, it will confirm the “Liquid level low”, issue an alarm, and proceed to a safe stop operation. If the “Liquid level low” switch is normal, it will be easy and safe. I can confirm. You may make it output the signal of liquid level low switch operation confirmation OK, without making a safe stop.
(6) When “Liquid level is low” is confirmed, an alarm is issued and the operation proceeds to the safe stop operation. As in the normal stop operation, the absorption liquid is automatically diluted and stopped after the dilution operation time has elapsed.
The inspection and operation confirmation as described above is usually performed by a driver who is accustomed to machine operation while confirming the safety status.In the present invention, this series of operations is incorporated into the control circuit. The “test operation mode” is intended to enable a person with relatively little expertise to easily and safely confirm the operation of the safety device by taking the “test operation mode”.
If an abnormality alarm is not issued even if the liquid level drops during this operation, the liquid level detection / control device 44 can determine that an abnormality has occurred. By this inspection operation, the empty can operation of the high temperature regenerator 10 due to the abnormality of the liquid level detection / control device 44 can be prevented. The absorption chiller / heater of the present invention may be equipped with such a safety check function. Furthermore, the absorption chiller / heater of the present invention has the above-mentioned two functions, and can be configured to have an operation control / safety control operation panel for easily checking the height and low of the liquid level to confirm safety. is there.
[0064]
In the present embodiment, the liquid level detection by the float 138 is described because the cycle of the sealed structure is targeted. As a method for detecting the liquid level, other methods such as an electrode type can be used.
In the liquid level detection / control device 44 shown in FIGS. 3 to 6, a float 138 equipped with a strong magnetic body (magnet 136) in a cylindrical liquid level detection pipe (vertical pipe 132) is adapted to the fluctuation of the liquid level. Go up and down. When the float 138 equipped with a strong magnetic material rises in the cylindrical liquid level detection tube and reaches the upper limit, the switch 140 provided outside the cylinder is activated (excited) by a magnetic force. When the float 138 equipped with a strong magnetic substance descends in the cylindrical liquid level detection tube and reaches the lower limit, the switch 142 provided outside the cylinder is activated (excited) by a magnetic force.
As a method of operating the switch, there are a method of pushing up the upper switch when the float is raised, and a method of pushing and operating the lower switch when the float is lowered. In addition, there is a system in which a lever is operated with a lever by a lever float switch.
[0065]
In the absorption chiller / heater of the present invention configured as described above, the temperature change on the load side is detected from the chilled / hot water temperature sensor 102 provided in the chilled / hot water outlet pipe from the evaporator 89, and the temperature change is controlled and operated. By introducing a control signal from the safety control operation panel 114 to the combustion device 18 or a fuel flow rate control valve (not shown), the fuel supplied to the high temperature regenerator 10 is increased or decreased, and the combustion amount of the combustion device 18 is increased or decreased. Efficient operation of the high temperature regenerator 10 is performed.
At the same time, each of the absorption liquid pumps 82, 85, and 93 is operated to stably supply and circulate absorption liquids having different water content ratios to perform continuous operation. That is, a part of the absorption liquid flowing into the absorption liquid pump 85 that supplies the liquid from the low temperature regenerator 84 to the medium temperature regenerator 87 is branched and bypassed to the return pipe by the bypass pipe 95, and at the same time the high temperature absorption from the intermediate temperature regenerator 87. A part of the liquid flowing into the liquid pump 93 is branched and bypassed by the bypass pipe 96, the supply / circulation amount of water / absorbed liquid is adjusted, the power load applied to the pumps 85, 93 is adjusted, and the energy is saved. And stable continuous operation.
[0066]
Further, the temperature of the load (cold / warm water) is detected by the cold / warm water temperature sensor 102, and the combustion pressure (heating amount) of the combustion device 18 is increased / decreased via the operation panel 114, and at the same time, the vapor pressure inside the high-temperature regenerator 10 increases. If the temperature detected by the steam drain temperature sensor at the outlet of the high-temperature regenerator of the absorption refrigerator heated by steam rises, the high-temperature absorbing liquid is passed through the operation panel 114 for safety. If the rotation speed of the pump 93 is increased to increase the liquid circulation rate and consequently the vapor pressure is lowered, and the drain temperature detected by the vapor drain temperature sensor decreases, the rotation of the high-temperature absorbing liquid pump 93 via the operation panel 114 The number of circulating fluids is reduced by lowering the number to increase the vapor pressure so that stable operation can be continued in a temperature range and pressure range suitable for continuous operation. Controlling the rotational speed of the pump 82 simultaneously with the pump 93 has the effect of further increasing the corresponding speed. Even if the pump 85 is operated at a constant speed without changing the rotation speed, the flow rate is adjusted by the bypass pipe 95, so that no problem occurs even if the rotation speed is not controlled.
[0067]
Or, simultaneously with increasing / decreasing the combustion amount (heating amount) of the combustion device 18 due to the temperature change of the load (cold / hot water), the vapor pressure inside the high-temperature regenerator 10 rises and the temperature rises, and the high-temperature regenerator outlet part If the temperature detected by the steam pipe or the temperature sensor detects that the temperature is detected by the temperature sensor, the rotational speed of the high-temperature absorption pump is increased for safety, and the liquid circulation rate is increased. If the steam pressure or temperature decreases, the rotation speed of the high-temperature absorption liquid pump 93 is decreased to reduce the liquid circulation rate and increase the steam pressure, and stable operation continues in the temperature range and pressure range suitable for continuous operation. It can be so. If the rotational speed of the pump 82 is increased or decreased at the same time as increasing or decreasing the rotational speed of the pump 93, the response speed increases and controllability is improved.
[0068]
Further, when the liquid level during operation of the high-temperature regenerator 10 is detected by the liquid level detection / control device 44 and the liquid level of the gas-liquid separator 26 rises, the rotational speed of the high-temperature absorbing liquid pump 93 is reduced. Reduce the liquid level by reducing the liquid circulation rate. On the other hand, when the liquid level falls, the number of rotations of the pump 93 is increased to increase the liquid circulation amount and control to raise the liquid level so that it does not rise above the tube plate surface 126. preferable. Further, when the operating liquid level of the high-temperature regenerator 10 further falls below the lower limit set value for safe operation, an alarm is issued via the operation panel 114 to interrupt combustion and enter a safe stop operation.
[0069]
In this case, as a method of detecting the liquid level during operation of the high-temperature regenerator 10 by the liquid level detection / control device 44 and controlling the rotational speed of the pump 93, the rotation determined in advance by receiving the operating conditions and the control signal. A method using a stepped control formula that changes the speed stepwise, a method using a continuous control formula that continuously changes the number of revolutions in response to operating conditions, load signals, and control signals is adopted. The
[0070]
The steam drain temperature, steam temperature, steam pressure, or boiler operating liquid level during operation is detected by a steam drain temperature sensor, steam temperature sensor, steam pressure gauge, or liquid level detector 44 to control the rotation speed of the pump. In this case, as a control method, each of the low temperature absorption liquid pump 82, the medium temperature absorption liquid pump 85, and the high temperature absorption liquid pump 93 is used simultaneously or independently, or only two of the low temperature absorption liquid pump 82 and the high temperature absorption liquid pump 93 are used. The operation method selected from a combination of the above can be switched to one method or a plurality of methods, and the rotational speed control is performed to control the supply amount (circulation amount) of the absorbing liquid containing water to increase the operation efficiency. In addition, each pump is controlled so as to ensure a rotation speed that does not cause a supply amount (circulation amount) shortage or a head (head) shortage.
[0071]
Further, during operation, when a supply device for supplying water / absorption liquid to the high-temperature regenerator 10, for example, the high-temperature absorption liquid pump 93 fails and the supply amount decreases, the high-temperature regenerator 10 holds it. Since the amount of water / absorbed liquid decreases and hinders continuous operation, an alarm is issued and at the same time, combustion is shut off and control is performed to enter a safe stop operation.
[0072]
Also, when the amount of water / absorbing liquid supplied to the high temperature regenerator 10 is reduced during operation, or when the amount of water / absorbing liquid held in the high temperature regenerator 10 is decreased, the temperature of each part is set to a safe operation setting value. When the temperature exceeds the range, the alarm is issued via the operation panel 114 by the high temperature regenerator 10 or the absorption liquid temperature sensor provided at the absorption liquid outlet of the high temperature regenerator 10 or the absorption liquid temperature sensor for preventing empty cans. Control to shut off combustion and enter safe stop operation.
[0073]
Next, the control flow will be described in more detail. First, the cold water outlet (inlet) temperature Tc1 detection → load control calculation → temperature detection of the exhaust hot water inlet temperature Th1 and the exhaust hot water heat exchanger 200 inlet absorption liquid temperature Tw1, and the exhaust hot water heat exchanger outlet hot water temperature Th2 are detected.
Judgment condition (1): When Th1-Tw1> set value
The flow control valve 178 to the heat recovery device side of the exhaust hot water control valve 178 is fully opened, and the entire amount flows to the exhaust heat regenerator 168. After confirming that the opening degree of the control valve 178 is 100%, normal combustion control is started. Next, load control calculation is performed, and combustion operation output control and operation output control of the exhaust hot water control valve 178 are performed. When the hot water temperature at the outlet of the waste heat water heat exchanger Th2 is equal to or lower than the set value, the control valve 178 is closed to reduce the amount of waste water that goes to the waste heat regenerator 168, and the temperature of the absorbed liquid at the waste heat water heat exchanger decreases. On the contrary, the absorption liquid is cooled).
At this time, if the amount of heating is smaller than the load, the amount of combustion control is increased to correct the shortage of the amount of warm water. When the amount of heating is larger than the load, the amount of combustion control is reduced to control the chilled water outlet (inlet) temperature Tc1 to be stable at the set temperature.
Even when the amount of heat of combustion is zero, when the amount of heat (waste water heat amount) is larger than the load and the chilled water outlet (inlet) temperature Tc1 decreases and is not stable at the set temperature, the absorption liquid flow rate that causes the absorption liquid to flow into the evaporator 89 The control valve 164 is opened to allow the absorption liquid to flow into the refrigerant pool 162 of the evaporator 89, and the refrigerant stored in the refrigerant pool 162 of the evaporator and the absorbed liquid are absorbed from the overflow weir 190 provided in the evaporator. Spill (return) the absorption liquid reservoir 202 of the vessel 81.
The absorption liquid flow rate adjustment valve 164 has a function of confirming the passage of time and the change of the cold water temperature Tc1, for example, whether the valve 164 is opened again after being opened for 5 seconds and then fully closed to check the cold water temperature Tc1. Since it is incorporated in the control device and includes a control that prevents the absorption liquid from flowing into the refrigerant pool more than necessary, the chilled water temperature is prevented from excessively rising. Therefore, the adverse effect on the external heat source device side is reduced, and the adverse effect on the cooling load side is also reduced, thereby preventing energy loss.
Preventing the cooling water outlet (inlet) temperature from dropping too low and operating the safety device by mixing the absorbing liquid into the refrigerant in the refrigerant pool 162 and spilling (returning) the refrigerant and the absorbing liquid into the absorbing liquid pool 202; and By continuing the flow of the exhaust warm water, the return temperature of the exhaust warm water is stabilized, and the adverse effect on the external heat source device, for example, the gas engine side is reduced. In addition, the absorption liquid that exchanges heat with the waste water does not drop too much due to the heat of the waste water, so it quickly starts up when the load increases while the operation is continued, and the amount of fuel that burns is reduced. Therefore, it is possible to increase the energy saving effect by effectively using the exhaust heat.
[0074]
Judgment condition (2): When Th1-Tw1 <setting value, or when Th1-Tw1 = setting value
The flow control circuit to the exhaust heat regenerator 168 side of the exhaust hot water control valve 178 is fully closed, and the entire amount exhaust heat regenerator 168 is bypassed. At this time, when there is a cooling load and there is a combustion operation output signal to the heating source, normal fuel combustion control is performed.
As other conditions, when the hot water control is possible at the time of start-up, the exhaust warm water control valve 178 is fully opened before the start of combustion, and then the control operation is such that the combustion control operation can be performed. At the time of stoppage, the exhaust hot water control valve 178 is fully closed, and the exhaust hot water is not sent to the exhaust heat regenerator 168, but the entire amount is bypassed.
[0075]
【The invention's effect】
Since this invention is comprised as mentioned above, there exist the following effects.
(1) Decreasing the temperature of the chilled water outlet (inlet) by mixing a part of the absorption liquid from the absorber into the refrigerant in the refrigerant pool and spilling (returning) the refrigerant and the absorption liquid into the absorption liquid reservoir of the absorber. If the temperature is too high, the operation of the safety device can be prevented, and the return temperature of the exhaust water can be stabilized by continuously flowing the exhaust water, thereby reducing the adverse effect on the external heat source equipment such as the gas engine.
(2) Absorption liquid that exchanges heat with waste water does not drop too much due to the heat of the waste water, rises quickly when the load increases during operation, and reduces the amount of fuel burned Therefore, it is possible to increase the energy saving effect by effectively using the exhaust heat.
(3) If the liquid level detection / control device does not confirm the operation of the “high” switch at startup, the operation control / safety control operation panel will determine that the liquid level detection / control device is abnormal and Since a control circuit having a control function for giving an alarm without entering and not entering into the combustion operation is provided, it is possible to prevent an empty can operation of the high-temperature regenerator.
(4) If an alarm is not issued even if the liquid level drops during operation, the liquid level detection / control device has a safety check function that can be judged as abnormal. An empty can operation of the high temperature regenerator due to an abnormality of the control device can be prevented.
[Brief description of the drawings]
FIG. 1 is a systematic schematic configuration diagram of a triple effect absorption chiller / heater having an exhaust heat regenerator according to a first embodiment of the present invention.
2 is a schematic configuration diagram showing a once-through type high-temperature regenerator and a liquid level detection / control device in the cold / hot water machine of FIG. 1. FIG.
FIG. 3 is a configuration diagram showing details of the liquid level detection / control device in FIG. 2;
FIG. 4 is a configuration diagram when the float is at an intermediate position in the liquid level detection / control device.
FIG. 5 is a configuration diagram when the float rises in the liquid level detection / control device.
FIG. 6 is a configuration diagram when the float is lowered in the liquid level detection / control device.
FIG. 7 is a systematic schematic configuration diagram showing an example of a conventional absorption chiller / heater.
[Explanation of symbols]
10 High temperature regenerator
12 Upper header
14 Lower header
16 Ascending pipe
18 Combustion device
20 Combustion chamber
24 Gas-liquid mixture conduit
26 Gas-liquid separator
28 Refrigerant vapor pipe
30 Absorption liquid extraction conduit
36 Absorption liquid circulation conduit
42 Absorption liquid supply pipe (water / absorption liquid supply pipe)
43 Liquid level detector
44 Liquid level detection and control device
48 Absorption type water heater
81 Absorber
82 Low temperature absorption liquid pump
83 Low temperature heat exchanger
84 Low temperature regenerator
85 Medium temperature absorption liquid pump
86 Medium temperature heat exchanger
87 Medium temperature regenerator
88 condenser
89 Evaporator
90 Refrigerant pump
93 High-temperature absorption liquid pump
94 High temperature heat exchanger
95, 96 Bypass pipe
97, 98 Refrigerant vapor pipe
99 Cold and hot water pump
100 Cooling water pump
102 Cold / hot water temperature sensor
114 Operation control / safety control operation panel
126 Tube plate surface
128 Upper liquid inlet / outlet pipe
130 Lower liquid inlet / outlet pipe
132 Vertical pipe
134 Liquid level
136 Magnet
138 Float
140 High liquid level detection switch
142 Low liquid level detection switch
151 First cooling / heating switching valve
160, 166 Branched absorption liquid tube
162 Refrigerant liquid pool
164 Absorbent flow control valve
168 Waste heat regenerator
170 Waste water inlet pipe
172 Waste water outlet pipe
174, 176 Hot water temperature sensor
178 Waste water flow control valve
180 Absorption liquid tube
182 Absorbent temperature sensor
184 Second cooling / heating switching valve
186 Refrigerant drain heat exchanger
188 Exhaust gas heat exchanger
190 Weir for overflow
192 Absorption liquid pipe from exhaust heat regenerator
194, 196 Refrigerant vapor pipe
200 Waste heat water heat exchanger
202 Absorption liquid reservoir

Claims (8)

A triple-effect absorption chiller / heater that integrates a high-temperature regenerator and a double-effect absorption chiller / heater using a once-through boiler or a boiler having the same structure as a once-through boiler. , High-temperature regenerator, medium-temperature regenerator, low-temperature regenerator, condenser, absorber, evaporator, heat exchanger, solution pump and refrigerant pump. Next, in the reverse flow triple effect absorption chiller / heater that leads to the high-temperature regenerator, the exhaust heat from the outside is recovered and used as a heating source, and the absorption liquid is heated and absorbed by the absorption liquid. An exhaust heat regenerator is provided in front of the low temperature regenerator to heat and evaporate the absorption liquid, and the ratio of the amount of heating heat that raises the concentration of the absorption liquid by heating the absorption liquid in the low temperature regenerator from the outside. Increase or decrease the amount of exhaust heat recovered By reducing the amount of heat exchange in the low-temperature regenerator, heating and concentrating the absorption liquid generated in the high-temperature regenerator and medium-temperature regenerator to reduce the amount of refrigerant vapor generated as a heating source for the low-temperature regenerator Waste water control valve for reducing the amount of fuel used for heating in the high-temperature regenerator, saving energy , recovering external exhaust heat and using it as a heat source for the exhaust heat regenerator When the exhaust water temperature at the inlet of the exhaust heat regenerator is higher than the temperature of the absorption liquid heated in the exhaust heat regenerator by controlling the exhaust water control valve, Warm water flows into the waste heat regenerator to heat the absorption liquid, and the temperature of the waste water temperature does not adversely affect the operating conditions and efficiency of the heat source system equipment that is the heat source that generates external waste heat. So that the temperature of the return waste water is reduced And controlled using, discharging hot water flows into the exhaust heat regenerator, the absorbent solution triple effect type absorption chiller having a heat regenerator, characterized in that so as to heat the. The triple effect type absorption chiller / heater having a waste heat regenerator according to claim 1, wherein a waste heat water three-way control valve for controlling a flow rate of the waste heat hot water is provided at an exhaust heat regenerator inlet. The triple effect type absorption chiller / heater having a waste heat regenerator according to claim 1, wherein a waste heat water three-way control valve for controlling the flow rate of the waste heat hot water is provided at the outlet of the waste heat regenerator. The absorption pump outlet of the absorber and the evaporator are connected via an absorption liquid distribution pipe having a flow control valve, and the temperature sensor provided in the cold water outlet pipe or the cold water inlet pipe of the evaporator and the flow control valve are connected. Via the control device, it is possible to control the amount of absorbed liquid flowing into the evaporator according to the temperature detected by the temperature sensor, and further, the refrigerant accumulated in the evaporator refrigerant pool and the absorbed liquid flowing into the evaporator are overflowed. absorber liquid either by falling into reservoir or back as in claims 1 triple effect type absorption chiller having a heat regenerator as set forth in use weir or overflow pipe. In the high temperature regenerator due to load fluctuations during partial load operation in which the exhaust heat is passed through the exhaust heat regenerator and the exhaust heat is recovered and the combustion heat reduction operation is performed and the combustion device of the high temperature regenerator is used to perform the combustion operation In order to prevent the liquid level of the liquid from fluctuating and causing a safe stop due to empty can operation or low liquid level, the amount of liquid absorbed by the absorbent pump is controlled to ensure the amount of liquid circulating to the high-temperature regenerator. stable triple effect type absorption chiller having a heat regenerator of claim 1 wherein the operation is to allow Te. As heat regenerator flows through the tube heating fluid, the heat regenerator of claim 1 wherein to use a shell-and-tube heat exchanger of the pool boiling system through the outer tube is diluted absorption solution Triple-effect absorption cold / hot water machine. The rare-boiling liquid outlet of the pool boiling type shell and tube heat exchanger is provided near the uppermost stage of the heat transfer tube group constituting the shell and tube type heat exchanger, and the heat transfer tube group 7. The exhaust heat according to claim 6 , wherein the arrangement of the heat transfer tubes at the uppermost stage and the lower stage of the pipe is such that the outflow of the surfactant added to the absorbent from the rare absorbent outlet is not inhibited. Triple effect absorption chiller / heater with regenerator. The triple-effect absorption chiller / heater having a waste heat regenerator according to claim 7 , wherein the arrangement of the heat transfer tubes at the uppermost stage and the lower stage of the waste heat regenerator is arranged in a grid pattern .

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