JP6066072B2

JP6066072B2 - Water heating system

Info

Publication number: JP6066072B2
Application number: JP2013041623A
Authority: JP
Inventors: 和之大谷; 立樹杉浦; 大沢　智也; 智也大沢
Original assignee: Miura Co Ltd
Current assignee: Miura Co Ltd
Priority date: 2013-03-04
Filing date: 2013-03-04
Publication date: 2017-01-25
Anticipated expiration: 2033-03-04
Also published as: JP2014169820A

Description

本発明は、ヒートポンプを用いた給水加温システムに関するものである。 The present invention relates to a feed water heating system using a heat pump.

従来、下記特許文献１に開示されるように、ボイラ（２４）の給水タンク（２３）への給水を、ヒートポンプ（１２）を用いて加温できるシステムが知られている。また、出願人は、この従来技術に比べてヒートポンプの効率をさらに向上した給水加温システムを提案し、既に特許出願を済ませている（特願２０１２−７９１９１）。 Conventionally, as disclosed in Patent Document 1 below, a system capable of heating water supplied to a water supply tank (23) of a boiler (24) using a heat pump (12) is known. In addition, the applicant has proposed a feed water warming system in which the efficiency of the heat pump is further improved as compared with this prior art, and has already filed a patent application (Japanese Patent Application No. 2012-79191).

この出願中の給水加温システムは、ヒートポンプと給水タンクとを備え、給水路を介した給水タンクへの給水は、廃熱回収熱交換器、過冷却器および凝縮器を順に通される。廃熱回収熱交換器は、給水路を介した給水タンクへの給水と、蒸発器を通過後の熱源流体との間接熱交換器であり、過冷却器は、給水路を介した給水タンクへの給水と、凝縮器から膨張弁への冷媒との間接熱交換器である。給水路を介した給水タンクへの給水中、ヒートポンプを運転すると共に、ヒートポンプの凝縮器の出口側水温を設定温度に維持するように、凝縮器への通水量を調整するのが好ましい。 The water supply warming system in this application includes a heat pump and a water supply tank, and water supplied to the water supply tank via the water supply path is sequentially passed through a waste heat recovery heat exchanger, a supercooler, and a condenser. The waste heat recovery heat exchanger is an indirect heat exchanger between the water supply to the water supply tank via the water supply channel and the heat source fluid after passing through the evaporator, and the supercooler to the water supply tank via the water supply channel Indirect heat exchanger between the water supply and the refrigerant from the condenser to the expansion valve. It is preferable to adjust the amount of water flow to the condenser so that the heat pump is operated during water supply to the water supply tank via the water supply path, and the outlet water temperature of the condenser of the heat pump is maintained at the set temperature.

特開２０１０−２５４３１号公報（図２、図３）JP 2010-25431 A (FIGS. 2 and 3)

しかしながら、給水タンクへの給水を常に廃熱回収熱交換器に通すのでは、廃熱回収熱交換器に通される熱源流体と給水との温度関係によっては、給水の加温ができないおそれがある。 However, if the feed water to the feed water tank is always passed through the waste heat recovery heat exchanger, the feed water may not be heated depending on the temperature relationship between the heat source fluid passed through the waste heat recovery heat exchanger and the feed water. .

また、熱源流体の温度によっては、給水タンクへの給水と熱源流体とを間接熱交換すれば足り、ヒートポンプを運転する必要がない場合がある。たとえば、凝縮器の出口側水温を設定温度に維持するように、凝縮器への通水量を調整する制御を行う場合において、その設定温度よりも熱源流体の温度が高い場合にまで、ヒートポンプを運転するのは無駄である。 Depending on the temperature of the heat source fluid, indirect heat exchange between the water supply to the water supply tank and the heat source fluid is sufficient, and there is a case where it is not necessary to operate the heat pump. For example, when controlling the flow rate of water to the condenser so that the outlet water temperature of the condenser is maintained at the set temperature, the heat pump is operated until the temperature of the heat source fluid is higher than the set temperature. It is useless to do.

さらに、凝縮器への通水量、言い換えれば給水路を介した給水タンクへの給水流量が少ないと、凝縮器における冷媒と水との熱交換量が減少し、システムを安定的に運用できないおそれがある。たとえば、吐出圧を設定値に維持するように圧縮機をインバータ制御すると共に、給水タンクの水位に基づき凝縮器への通水量を調整する制御を行う場合、凝縮器への通水量が減ると、凝縮器における冷媒と水との熱交換量が減少し、圧縮機の回転数（周波数）も減少するが、設定周波数以下では、吐出圧が上昇して圧縮機が停止するおそれがある。そのため、給水流量が減少したり、圧縮機への電源周波数が減少したりした場合には、凝縮器における熱交換量を増す必要がある。 Furthermore, if the water flow rate to the condenser, in other words, the feed water flow rate to the feed tank via the feed channel is small, the amount of heat exchange between the refrigerant and water in the condenser may decrease, and the system may not operate stably. is there. For example, when the compressor is controlled by an inverter so as to maintain the discharge pressure at a set value and the control for adjusting the amount of water flow to the condenser based on the water level of the water supply tank is performed, if the amount of water flow to the condenser decreases, The amount of heat exchange between the refrigerant and water in the condenser is reduced, and the rotation speed (frequency) of the compressor is also reduced. However, if the frequency is lower than the set frequency, the discharge pressure may increase and the compressor may stop. Therefore, when the feed water flow rate decreases or the power supply frequency to the compressor decreases, it is necessary to increase the heat exchange amount in the condenser.

本発明が解決しようとする課題は、熱源流体や給水の温度に応じて、最適な条件で給水を加温できる給水加温システムを提供することにある。また、給水流量や圧縮機への電源周波数が減少した場合には、凝縮器における熱交換量を増やすことで圧縮機の停止を防止できる給水加温システムを提供することを課題とする。 The problem to be solved by the present invention is to provide a feed water warming system capable of warming feed water under optimum conditions according to the temperature of the heat source fluid and the feed water. Another object of the present invention is to provide a feed water heating system that can prevent the compressor from being stopped by increasing the amount of heat exchange in the condenser when the feed water flow rate or the power supply frequency to the compressor decreases.

本発明は、前記課題を解決するためになされたもので、請求項１に記載の発明は、圧縮機、凝縮器、膨張弁および蒸発器が順次環状に接続されて冷媒を循環させ、前記蒸発器に通される熱源流体から熱をくみ上げ、前記凝縮器に通される水を加温するヒートポンプと、廃熱回収熱交換器、過冷却器および前記凝縮器を順に通されて給水路により給水可能な給水タンクとを備え、前記廃熱回収熱交換器は、前記給水路を介した前記給水タンクへの給水と、前記蒸発器を通過後の熱源流体との間接熱交換器であり、前記過冷却器は、前記給水路を介した前記給水タンクへの給水と、前記凝縮器から前記膨張弁への冷媒との間接熱交換器であり、前記過冷却器への給水を、前記廃熱回収熱交換器に通してから前記過冷却器へ供給するか、前記廃熱回収熱交換器に通さずに前記過冷却器へ供給するかを切替可能とされたことを特徴とする給水加温システムである。 The present invention has been made to solve the above problems, and the invention according to claim 1 is characterized in that a compressor, a condenser, an expansion valve, and an evaporator are sequentially connected in an annular manner to circulate a refrigerant, and the evaporation. Heat is pumped from the heat source fluid that is passed through the condenser, and the heat pump that heats the water that is passed through the condenser, the waste heat recovery heat exchanger, the supercooler, and the condenser are passed through the water supply passage in order. The waste heat recovery heat exchanger is an indirect heat exchanger between the water supply to the water supply tank via the water supply channel and the heat source fluid after passing through the evaporator, The subcooler is an indirect heat exchanger for supplying water to the water supply tank via the water supply channel and refrigerant from the condenser to the expansion valve, and supplying water to the subcooler to the waste heat It is passed through a recovery heat exchanger and then supplied to the subcooler or the waste heat circuit A water supply warming system, wherein said that whether to supply to the subcooler is capable of switching without passing through the heat exchanger.

請求項１に記載の発明によれば、給水タンクへの給水は、廃熱回収熱交換器、過冷却器および凝縮器を順に通される一方、ヒートポンプの熱源流体は、蒸発器および廃熱回収熱交換器を順に通される。蒸発器を通過後の熱源流体の熱や、凝縮器を通過後の冷媒の熱を用いて、凝縮器への給水を予熱しておくことで、ヒートポンプの効率を向上することができる。但し、過冷却器への給水を廃熱回収熱交換器に通すか否かは切替可能であるから、熱源流体や給水の温度に応じて、最適な条件で給水を加温することができる。 According to the first aspect of the present invention, the water supplied to the water supply tank is passed through the waste heat recovery heat exchanger, the subcooler, and the condenser in turn, while the heat source fluid of the heat pump is the evaporator and the waste heat recovery. The heat exchanger is passed in order. The efficiency of the heat pump can be improved by preheating the feed water to the condenser using the heat of the heat source fluid after passing through the evaporator and the heat of the refrigerant after passing through the condenser. However, since it is possible to switch whether or not the feed water to the supercooler is passed through the waste heat recovery heat exchanger, the feed water can be heated under optimum conditions according to the temperature of the heat source fluid and the feed water.

請求項２に記載の発明は、前記給水タンクの水位に基づき、前記給水路を介した前記給水タンクへの給水を制御し、前記給水路を介した前記給水タンクへの給水中、前記凝縮器の出口側の水温を設定温度に維持するように通水量を調整し、前記蒸発器の入口側の熱源流体温度が前記設定温度以上である場合、前記給水路を介した前記給水タンクへの給水中、前記圧縮機を停止すると共に、前記給水タンクへの給水を前記廃熱回収熱交換器に通すことを特徴とする請求項１に記載の給水加温システムである。 The invention according to claim 2 controls the water supply to the water supply tank via the water supply path based on the water level of the water supply tank, the water supply to the water supply tank via the water supply path, the condenser When the amount of water flow is adjusted so that the water temperature on the outlet side of the evaporator is maintained at the set temperature, and the heat source fluid temperature on the inlet side of the evaporator is equal to or higher than the set temperature, the water supply to the water supply tank via the water supply path The feed water heating system according to claim 1, wherein the compressor is stopped and water supplied to the water supply tank is passed through the waste heat recovery heat exchanger.

請求項２に記載の発明によれば、給水路を介した給水タンクへの給水中、凝縮器の出口側水温を設定温度に維持するように、凝縮器への通水量（給水路を介した給水タンクへの給水流量）を調整することで、給水源の水温や熱源流体の温度に拘わらず、所望温度の温水を得ることができる。また、熱源流体温度が前記設定温度以上である場合、廃熱回収熱交換器において熱源流体により給水を加温すれば足り、圧縮機を停止することができる。 According to the second aspect of the present invention, the amount of water flow to the condenser (via the water supply channel) is maintained so that the water temperature on the outlet side of the condenser is maintained at the set temperature during the water supply to the water supply tank via the water supply channel. Regardless of the water temperature of the water supply source or the temperature of the heat source fluid, hot water having a desired temperature can be obtained by adjusting the water supply flow rate to the water supply tank. Further, when the heat source fluid temperature is equal to or higher than the set temperature, it is sufficient to heat the water supply with the heat source fluid in the waste heat recovery heat exchanger, and the compressor can be stopped.

請求項３に記載の発明は、前記蒸発器の入口側の熱源流体温度が前記設定温度未満である場合、前記給水路を介した前記給水タンクへの給水中、前記圧縮機を運転し、前記廃熱回収熱交換器の入口側の水温が前記蒸発器の出口側または入口側の熱源流体温度以下の場合、前記給水タンクへの給水を前記廃熱回収熱交換器に通し、前記廃熱回収熱交換器の入口側の水温が前記蒸発器の出口側または入口側の熱源流体温度を超える場合、前記給水タンクへの給水を前記廃熱回収熱交換器に通さないことを特徴とする請求項２に記載の給水加温システムである。 According to a third aspect of the present invention, when the heat source fluid temperature on the inlet side of the evaporator is lower than the set temperature, the compressor is operated during water supply to the water supply tank via the water supply path, When the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or lower than the heat source fluid temperature on the outlet side or the inlet side of the evaporator, water supplied to the water supply tank is passed through the waste heat recovery heat exchanger, and the waste heat recovery is performed. The water supply to the water supply tank is not passed through the waste heat recovery heat exchanger when the water temperature on the inlet side of the heat exchanger exceeds the heat source fluid temperature on the outlet side or the inlet side of the evaporator. 2. A water heating system according to 2.

請求項３に記載の発明によれば、熱源流体温度が前記設定温度未満である場合、給水タンクへの給水中、圧縮機を運転するが、廃熱回収熱交換器の入口側水温が熱源流体温度を超える場合、給水タンクへの給水を廃熱回収熱交換器に通さないことで、給水タンクへの給水が廃熱回収熱交換器において万一冷却されるという不都合を防止することができる。 According to the third aspect of the present invention, when the heat source fluid temperature is lower than the set temperature, the compressor is operated while supplying water to the feed water tank, but the inlet side water temperature of the waste heat recovery heat exchanger is the heat source fluid. When the temperature is exceeded, the water supply to the water supply tank is not passed through the waste heat recovery heat exchanger, so that the inconvenience that the water supply to the water supply tank is cooled by the waste heat recovery heat exchanger can be prevented.

請求項４に記載の発明は、前記給水タンクは、同一の給水源から、前記給水路により給水可能とされると共に、前記廃熱回収熱交換器、前記過冷却器および前記凝縮器のいずれも介さずに補給水路により給水可能とされ、前記廃熱回収熱交換器の入口側の水温が前記設定温度以上である場合、前記圧縮機を停止すると共に前記給水路を介した前記給水タンクへの給水を停止した状態で、前記給水タンクの水位に基づき前記補給水路を介した前記給水タンクへの給水を制御することを特徴とする請求項２または請求項３に記載の給水加温システムである。 According to a fourth aspect of the present invention, the water supply tank can be supplied with water from the same water supply source through the water supply channel, and any of the waste heat recovery heat exchanger, the subcooler and the condenser can be used. If the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or higher than the set temperature, the compressor is stopped and the water tank is connected to the water tank via the water supply channel. 4. The feed water heating system according to claim 2, wherein water supply to the water supply tank is controlled via the makeup water channel based on a water level of the water supply tank in a state where water supply is stopped. 5. .

請求項４に記載の発明によれば、廃熱回収熱交換器の入口側水温が前記設定温度以上である場合、廃熱回収熱交換器やヒートポンプを用いずに、補給水路を介して給水タンクへ給水すれば足りる。 According to the fourth aspect of the present invention, when the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or higher than the set temperature, the water supply tank is provided via the make-up water channel without using the waste heat recovery heat exchanger or the heat pump. It is enough to supply water.

請求項５に記載の発明は、前記給水タンクの水位に基づき、前記給水路を介した前記給水タンクへの給水を制御し、前記給水路を介した前記給水タンクへの給水流量が設定流量以下になると、前記給水タンクへの給水を前記廃熱回収熱交換器に通さないことを特徴とする請求項１に記載の給水加温システムである。 Invention of Claim 5 controls the water supply to the said water supply tank via the said water supply path based on the water level of the said water supply tank, and the water supply flow volume to the said water supply tank via the said water supply path is below setting flow volume Then, the feed water heating system according to claim 1, wherein the feed water to the feed water tank is not passed through the waste heat recovery heat exchanger.

請求項５に記載の発明によれば、給水流量が減少した場合、給水タンクへの給水を廃熱回収熱交換器に通さないことで、凝縮器における熱交換量を増やし、圧縮機の停止を防止することができる。 According to the invention described in claim 5, when the feed water flow rate decreases, the heat exchange amount in the condenser is increased by not passing the feed water to the feed water tank through the waste heat recovery heat exchanger, and the compressor is stopped. Can be prevented.

請求項６に記載の発明は、前記圧縮機は、吐出圧を設定値に維持するように、モータの電源周波数をインバータにより変えることで出力を制御され、前記周波数が設定周波数以下になると、前記給水タンクへの給水を前記廃熱回収熱交換器に通さないことを特徴とする請求項１または請求項５に記載の給水加温システムである。 According to a sixth aspect of the present invention, the compressor is controlled in output by changing the power supply frequency of the motor by an inverter so as to maintain the discharge pressure at a set value. The feed water heating system according to claim 1 or 5, wherein feed water to the feed water tank is not passed through the waste heat recovery heat exchanger.

請求項６に記載の発明によれば、圧縮機への電源周波数が減少した場合、給水タンクへの給水を廃熱回収熱交換器に通さないことで、凝縮器における熱交換量を増やし、圧縮機の停止を防止することができる。 According to the invention described in claim 6, when the power supply frequency to the compressor is decreased, the heat exchange amount in the condenser is increased by not passing the feed water to the feed water tank through the waste heat recovery heat exchanger, and the compression is performed. The machine can be prevented from stopping.

さらに、請求項７に記載の発明は、前記廃熱回収熱交換器の入口側の水温が前記蒸発器の出口側の熱源流体温度以下の場合、前記給水路を介した前記給水タンクへの給水中、前記給水タンクへの給水を前記廃熱回収熱交換器に通し、前記廃熱回収熱交換器の入口側の水温が前記蒸発器の出口側の熱源流体温度を超える場合、前記給水路を介した前記給水タンクへの給水中、前記給水タンクへの給水を前記廃熱回収熱交換器に通さないことを特徴とする請求項５または請求項６に記載の給水加温システムである。 Furthermore, in the invention according to claim 7, when the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or lower than the heat source fluid temperature on the outlet side of the evaporator, the water supply to the water supply tank via the water supply path The water supply to the water supply tank is passed through the waste heat recovery heat exchanger, and the water temperature on the inlet side of the waste heat recovery heat exchanger exceeds the heat source fluid temperature on the outlet side of the evaporator, The feed water heating system according to claim 5 or 6, wherein the feed water to the feed water tank is not passed through the waste heat recovery heat exchanger.

請求項７に記載の発明によれば、廃熱回収熱交換器の入口側水温が熱源流体温度を超える場合、給水タンクへの給水を廃熱回収熱交換器に通さないことで、給水タンクへの給水が廃熱回収熱交換器において万一冷却されるという不都合を防止することができる。 According to the invention described in claim 7, when the water temperature on the inlet side of the waste heat recovery heat exchanger exceeds the heat source fluid temperature, the water supply to the water supply tank is not passed through the waste heat recovery heat exchanger, thereby supplying the water supply tank. Can be prevented from being disadvantageously cooled in the waste heat recovery heat exchanger.

本発明によれば、熱源流体や給水の温度に応じて、最適な条件で給水を加温することができる。また、給水流量や圧縮機への電源周波数が減少した場合には、凝縮器における熱交換量を増やすことで圧縮機の停止を防止することができる。 ADVANTAGE OF THE INVENTION According to this invention, water supply can be heated on optimal conditions according to the temperature of heat-source fluid or water supply. Further, when the feed water flow rate or the power supply frequency to the compressor decreases, the compressor can be prevented from stopping by increasing the heat exchange amount in the condenser.

本発明の給水加温システムの実施例１および実施例２を示す概略図である。It is the schematic which shows Example 1 and Example 2 of the feed water heating system of this invention.

以下、本発明の具体的実施例を図面に基づいて詳細に説明する。 Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

図１は、本発明の給水加温システム１の実施例１を示す概略図である。 FIG. 1 is a schematic diagram showing a first embodiment of a feed water warming system 1 of the present invention.

本実施例の給水加温システム１は、ボイラ２の給水タンク３への給水をヒートポンプ４で加温できるシステムであり、ボイラ２への給水を貯留する給水タンク３と、この給水タンク３への給水を貯留する補給水タンク５と、この補給水タンク５から給水タンク３への給水を加温するヒートポンプ４と、このヒートポンプ４の熱源としての熱源水（たとえば廃温水）を貯留する熱源水タンク６とを備える。 The feed water warming system 1 of the present embodiment is a system that can heat the feed water to the feed water tank 3 of the boiler 2 with the heat pump 4. The feed water tank 3 that stores the feed water to the boiler 2, and the feed water tank 3 A replenishment water tank 5 for storing water supply, a heat pump 4 for heating water supplied from the replenishment water tank 5 to the water supply tank 3, and a heat source water tank for storing heat source water (for example, waste hot water) as a heat source of the heat pump 4. 6.

ボイラ２は、蒸気ボイラであり、給水タンク３からの給水を加熱して蒸気にする。ボイラ２は、典型的には、蒸気の圧力を所望に維持するように、燃焼量を調整される。また、ボイラ２は、缶体内の水位を所望に維持するように、給水タンク３からボイラ２への給水路またはボイラ２の内部に設けたポンプ７が制御される。ボイラ２からの蒸気は、各種の蒸気使用設備（図示省略）へ送られるが、蒸気使用設備からのドレン（蒸気の凝縮水）を給水タンク３へ戻してもよい。 The boiler 2 is a steam boiler, and heats the feed water from the feed water tank 3 into steam. The boiler 2 is typically adjusted in combustion quantity so as to maintain the desired steam pressure. Moreover, the pump 7 provided in the inside of the water supply path from the water supply tank 3 to the boiler 2, or the boiler 2 is controlled so that the boiler 2 may maintain the water level in a can body as desired. The steam from the boiler 2 is sent to various steam use facilities (not shown), but drain (condensed water of steam) from the steam use facility may be returned to the water supply tank 3.

給水タンク３は、補給水タンク５から、ヒートポンプ４を介して給水路８により給水可能であると共に、ヒートポンプ４を介さずに補給水路９により給水可能である。給水路８に設けた給水ポンプ１０と、補給水路９に設けた補給水ポンプ１１との作動を制御することで、給水路８と補給水路９との内、いずれか一方または双方を介して、補給水タンク５から給水タンク３へ給水可能である。 The water supply tank 3 can be supplied with water from the make-up water tank 5 via the heat pump 4 through the water supply path 8 and can be supplied through the make-up water path 9 without going through the heat pump 4. By controlling the operation of the water supply pump 10 provided in the water supply path 8 and the makeup water pump 11 provided in the makeup water path 9, via either one or both of the water supply path 8 and the makeup water path 9, Water can be supplied from the makeup water tank 5 to the water supply tank 3.

給水ポンプ１０は、本実施例では、インバータにより回転数を制御可能とされる。給水ポンプ１０の回転数を変更することで、給水路８を介した給水タンク３への給水流量を調整することができる。一方、補給水ポンプ１１は、本実施例では、オンオフ制御される。 In the present embodiment, the feed water pump 10 can control the rotation speed by an inverter. By changing the rotation speed of the water supply pump 10, the water supply flow rate to the water supply tank 3 through the water supply path 8 can be adjusted. On the other hand, the makeup water pump 11 is on / off controlled in this embodiment.

補給水タンク５は、給水タンク３への給水を貯留する。補給水タンク５への給水として、本実施例では軟水が用いられる。すなわち、軟水器（図示省略）にて水中の硬度分を除去された軟水は、補給水タンク５に供給され貯留される。補給水タンク５の水位に基づき軟水器からの給水を制御することで、補給水タンク５の水位は所望に維持される。 The makeup water tank 5 stores water supplied to the water supply tank 3. In this embodiment, soft water is used as the water supply to the makeup water tank 5. That is, the soft water from which the water hardness has been removed by the water softener (not shown) is supplied to the makeup water tank 5 and stored. By controlling the water supply from the water softener based on the water level of the makeup water tank 5, the water level of the makeup water tank 5 is maintained as desired.

ヒートポンプ４は、蒸気圧縮式のヒートポンプであり、圧縮機１２、凝縮器１３、膨張弁１４および蒸発器１５が順次環状に接続されて構成される。そして、圧縮機１２は、ガス冷媒を圧縮して高温高圧にする。また、凝縮器１３は、圧縮機１２からのガス冷媒を凝縮液化する。さらに、膨張弁１４は、凝縮器１３からの液冷媒を通過させることで、冷媒の圧力と温度とを低下させる。そして、蒸発器１５は、膨張弁１４からの冷媒の蒸発を図る。 The heat pump 4 is a vapor compression heat pump, and includes a compressor 12, a condenser 13, an expansion valve 14, and an evaporator 15 that are sequentially connected in an annular shape. The compressor 12 compresses the gas refrigerant to a high temperature and a high pressure. The condenser 13 condenses and liquefies the gas refrigerant from the compressor 12. Furthermore, the expansion valve 14 allows the liquid refrigerant from the condenser 13 to pass therethrough, thereby reducing the pressure and temperature of the refrigerant. The evaporator 15 evaporates the refrigerant from the expansion valve 14.

従って、ヒートポンプ４は、蒸発器１５において、冷媒が外部から熱を奪って気化する一方、凝縮器１３において、冷媒が外部へ放熱して凝縮することになる。これを利用して、本実施例では、ヒートポンプ４は、蒸発器１５において、熱源水から熱をくみ上げ、凝縮器１３において、給水路８の水を加温する。 Therefore, in the heat pump 4, the refrigerant takes heat from the outside and vaporizes in the evaporator 15, while the refrigerant dissipates heat to the outside and condenses in the condenser 13. In this embodiment, the heat pump 4 draws heat from the heat source water in the evaporator 15 and heats the water in the water supply channel 8 in the condenser 13.

ヒートポンプ４は、さらに、凝縮器１３と膨張弁１４との間に、過冷却器１６を備えるのが好ましい。過冷却器１６は、凝縮器１３から膨張弁１４への冷媒と、凝縮器１３への給水との間接熱交換器である。過冷却器１６により、凝縮器１３への給水で、凝縮器１３から膨張弁１４への冷媒を過冷却することができると共に、凝縮器１３から膨張弁１４への冷媒で、凝縮器１３への給水を加温することができる。ヒートポンプ４の冷媒は、好適には、凝縮器１３において潜熱を放出し、過冷却器１６において顕熱を放出する。 It is preferable that the heat pump 4 further includes a supercooler 16 between the condenser 13 and the expansion valve 14. The subcooler 16 is an indirect heat exchanger between the refrigerant from the condenser 13 to the expansion valve 14 and the feed water to the condenser 13. The subcooler 16 can supercool the refrigerant from the condenser 13 to the expansion valve 14 by supplying water to the condenser 13, and can supply the refrigerant to the condenser 13 by the refrigerant from the condenser 13 to the expansion valve 14. The water supply can be heated. The refrigerant of the heat pump 4 preferably releases latent heat in the condenser 13 and releases sensible heat in the subcooler 16.

つまり、凝縮器１３において、ガス冷媒は凝縮して液冷媒となり、その液冷媒が過冷却器１６に供給されて、過冷却器１６において、液冷媒はさらに冷却（過冷却）される。冷媒の凝縮用と過冷却用とで熱交換器を分けることで、熱交換器の設計が容易となり、熱交換器を簡易な構造で小型化でき、コスト削減を図ることができる。また、汎用の熱交換器の利用も可能となる。 That is, in the condenser 13, the gas refrigerant is condensed into a liquid refrigerant, and the liquid refrigerant is supplied to the subcooler 16, and the liquid refrigerant is further cooled (supercooled) in the subcooler 16. By separating heat exchangers for refrigerant condensation and supercooling, the heat exchanger can be easily designed, the heat exchanger can be reduced in size with a simple structure, and costs can be reduced. In addition, a general-purpose heat exchanger can be used.

その他、ヒートポンプ４には、圧縮機１２の入口側にアキュムレータを設置したり、圧縮機１２の出口側に油分離器を設置したり、凝縮器１３の出口側（凝縮器１３と過冷却器１６との間）に受液器を設置したりしてもよい。 In addition, in the heat pump 4, an accumulator is installed on the inlet side of the compressor 12, an oil separator is installed on the outlet side of the compressor 12, or the outlet side of the condenser 13 (the condenser 13 and the subcooler 16 A receiver may be installed between the two).

ところで、ヒートポンプ４は、その出力を変更可能とされてもよい。たとえば、圧縮機１２のモータの電源周波数ひいては回転数をインバータで変更することで、ヒートポンプ４の出力を変更することができる。 By the way, the heat pump 4 may be capable of changing its output. For example, the output of the heat pump 4 can be changed by changing the power supply frequency of the motor of the compressor 12 and thus the rotational speed by an inverter.

給水加温システム１は、さらに、廃熱回収熱交換器１７を備えるのが好ましい。この廃熱回収熱交換器１７は、過冷却器１６への給水と、蒸発器１５を通過後の熱源水との間接熱交換器である。従って、給水路８の水は、基本的には、廃熱回収熱交換器１７、過冷却器１６および凝縮器１３へと順に通されることになる。一方、熱源水タンク６の熱源水は、熱源供給路１８を介して、蒸発器１５を通された後、廃熱回収熱交換器１７に通される。 It is preferable that the feed water heating system 1 further includes a waste heat recovery heat exchanger 17. The waste heat recovery heat exchanger 17 is an indirect heat exchanger for supplying water to the subcooler 16 and heat source water after passing through the evaporator 15. Therefore, the water in the water supply channel 8 is basically passed through the waste heat recovery heat exchanger 17, the subcooler 16, and the condenser 13 in order. On the other hand, the heat source water in the heat source water tank 6 is passed through the evaporator 15 via the heat source supply path 18 and then passed to the waste heat recovery heat exchanger 17.

但し、給水路８を介した給水タンク３への給水は、廃熱回収熱交換器１７に通してから過冷却器１６へ供給するか、廃熱回収熱交換器１７に通さずに過冷却器１６へ供給するかを切替可能とされている。本実施例では、給水路８には、廃熱回収熱交換器１７の前後を接続するようにバイパス路１９が設けられており、給水路８とバイパス路１９との分岐部に設けた三方弁２０により、給水ポンプ１０からの給水を廃熱回収熱交換器１７に通すか否かが切り替えられる。但し、三方弁２０に代えて、給水路８とバイパス路１９には、互いの分岐部と合流部との間に、それぞれ開閉弁を設け、その開閉弁の開閉を制御してもよい。なお、廃熱回収熱交換器１７から過冷却器１６への給水路８には、バイパス路１９との合流部より上流側に逆止弁２１が設けられている。 However, water supplied to the water supply tank 3 through the water supply path 8 is supplied to the supercooler 16 after passing through the waste heat recovery heat exchanger 17, or is not supplied to the waste heat recovery heat exchanger 17 and is supplied to the subcooler. 16 can be switched. In this embodiment, a bypass passage 19 is provided in the water supply passage 8 so as to connect the front and rear of the waste heat recovery heat exchanger 17, and a three-way valve provided at a branch portion between the water supply passage 8 and the bypass passage 19. By 20, it is switched whether the feed water from the feed water pump 10 is passed through the waste heat recovery heat exchanger 17. However, in place of the three-way valve 20, the water supply channel 8 and the bypass channel 19 may be provided with an on-off valve between the branch portion and the junction portion, respectively, and the opening / closing of the on-off valve may be controlled. In addition, a check valve 21 is provided in the water supply path 8 from the waste heat recovery heat exchanger 17 to the supercooler 16 on the upstream side of the junction with the bypass path 19.

熱源水タンク６は、ヒートポンプ４の熱源としての熱源水を貯留する。熱源水とは、たとえば廃温水（工場などから排出される温水）である。なお、熱源水タンク６には、熱源水の供給路２２が設けられると共に、所定以上の水をあふれさせるオーバーフロー路２３が設けられている。 The heat source water tank 6 stores heat source water as a heat source of the heat pump 4. The heat source water is, for example, waste hot water (hot water discharged from a factory or the like). The heat source water tank 6 is provided with a heat source water supply path 22 and an overflow path 23 for overflowing a predetermined amount or more of water.

熱源水タンク６の熱源水は、熱源供給路１８を介して、ヒートポンプ４の蒸発器１５を通された後、廃熱回収熱交換器１７を通される。熱源供給路１８には、蒸発器１５より上流側に熱源供給ポンプ２４が設けられており、この熱源供給ポンプ２４を作動させることで、熱源水タンク６からの熱源水を、蒸発器１５と廃熱回収熱交換器１７とに順に通すことができる。 The heat source water in the heat source water tank 6 is passed through the evaporator 15 of the heat pump 4 via the heat source supply path 18 and then passed through the waste heat recovery heat exchanger 17. The heat source supply path 18 is provided with a heat source supply pump 24 on the upstream side of the evaporator 15. By operating the heat source supply pump 24, the heat source water from the heat source water tank 6 is discarded with the evaporator 15. The heat recovery heat exchanger 17 can be sequentially passed.

蒸発器１５を先に通した後に廃熱回収熱交換器１７に熱源水を通すことで、廃熱回収熱交換器１７を先に通した後に蒸発器１５に熱源水を通す場合と比較して、蒸発器１５における冷媒の蒸発温度（つまり蒸発圧力）を高めることができ、圧縮機１２の圧力比を小さくすることができ、省エネルギーを図ることができる。 By passing the heat source water through the waste heat recovery heat exchanger 17 after passing the evaporator 15 first, compared with the case where the heat source water is passed through the evaporator 15 after passing the waste heat recovery heat exchanger 17 first. In addition, the evaporation temperature (that is, the evaporation pressure) of the refrigerant in the evaporator 15 can be increased, the pressure ratio of the compressor 12 can be reduced, and energy can be saved.

給水路８には、凝縮器１３の出口側に、出湯温度センサ２５が設けられる。出湯温度センサ２５は、凝縮器１３を通過後の水温を検出する。出湯温度センサ２５の検出温度に基づき、給水ポンプ１０が制御される。ここでは、給水ポンプ１０は、出湯温度センサ２５の検出温度を設定温度（たとえば７５℃）に維持するようにインバータ制御される。つまり、給水路８を介した給水タンク３への給水は、出湯温度センサ２５の検出温度を設定温度に維持するように、流量が調整される。但し、場合により、このような出湯温度センサ２５による流量調整制御を省略することもできる。 In the water supply path 8, a hot water temperature sensor 25 is provided on the outlet side of the condenser 13. The hot water temperature sensor 25 detects the water temperature after passing through the condenser 13. Based on the temperature detected by the hot water temperature sensor 25, the feed water pump 10 is controlled. Here, the feed water pump 10 is inverter-controlled so as to maintain the temperature detected by the tapping temperature sensor 25 at a set temperature (for example, 75 ° C.). That is, the flow rate of water supplied to the water supply tank 3 via the water supply path 8 is adjusted so that the temperature detected by the tapping temperature sensor 25 is maintained at the set temperature. However, in some cases, such flow rate adjustment control by the tapping temperature sensor 25 can be omitted.

給水路８には、給水源の温度を検出する給水温度センサ２６が設けられる。給水温度センサ２６は、補給水タンク５に設けてもよいが、本実施例では、給水ポンプ１０と三方弁２０との間の給水路８に設けられている。 The water supply path 8 is provided with a water supply temperature sensor 26 that detects the temperature of the water supply source. The feed water temperature sensor 26 may be provided in the makeup water tank 5, but in this embodiment, it is provided in the feed water path 8 between the feed water pump 10 and the three-way valve 20.

給水タンク３には、水位検出器２７が設けられる。この水位検出器２７は、その構成を特に問わないが、本実施例では電極式水位検出器とされる。この場合、給水タンク３には、長さの異なる複数の電極棒２８〜３０が、その下端部の高さ位置を互いに異ならせて差し込まれて保持されている。本実施例では、給水停止電極棒２８、給水開始電極棒２９および負荷切替電極棒３０が、順に下端部の高さ位置を低くして、給水タンク３に挿入されている。各電極棒２８〜３０は、その下端部が水に浸かるか否かにより、下端部における水位の有無を検出する。 A water level detector 27 is provided in the water supply tank 3. The configuration of the water level detector 27 is not particularly limited. In the present embodiment, the water level detector 27 is an electrode type water level detector. In this case, a plurality of electrode rods 28 to 30 having different lengths are inserted and held in the water supply tank 3 with their lower end portions having different height positions. In the present embodiment, the water supply stop electrode rod 28, the water supply start electrode rod 29, and the load switching electrode rod 30 are inserted into the water supply tank 3 with the height position of the lower end portion lowered in order. Each electrode rod 28-30 detects the presence or absence of the water level in a lower end part by whether the lower end part is immersed in water.

熱源水タンク６には、熱源水の有無を確認するために、水位検出器３１が設けられる。この水位検出器３１は、その構成を特に問わないが、本実施例では電極式水位検出器とされる。この場合、熱源水タンク６には、低水位検出電極棒３２が差し込まれており、熱源水の水位が設定を下回っていないかを監視する。 The heat source water tank 6 is provided with a water level detector 31 in order to confirm the presence or absence of the heat source water. The configuration of the water level detector 31 is not particularly limited, but is an electrode type water level detector in the present embodiment. In this case, the low water level detection electrode rod 32 is inserted into the heat source water tank 6 and it is monitored whether the water level of the heat source water is below the setting.

熱源水タンク６には、熱源水の温度を検出する第一熱源温度センサ３３が設けられる。但し、第一熱源温度センサ３３は、熱源水タンク６から蒸発器１５への熱源供給路１８に設けてもよい。また、熱源水の温度検出は、蒸発器１５の入口側（熱源水タンク６を含む）に加えて、蒸発器１５の出口側においても行ってもよい。図示例では、熱源水タンク６に第一熱源温度センサ３３が設けられ、蒸発器１５と廃熱回収熱交換器１７との間の熱源供給路１８に第二熱源温度センサ３４が設けられている。 The heat source water tank 6 is provided with a first heat source temperature sensor 33 that detects the temperature of the heat source water. However, the first heat source temperature sensor 33 may be provided in the heat source supply path 18 from the heat source water tank 6 to the evaporator 15. The temperature detection of the heat source water may also be performed on the outlet side of the evaporator 15 in addition to the inlet side of the evaporator 15 (including the heat source water tank 6). In the illustrated example, a first heat source temperature sensor 33 is provided in the heat source water tank 6, and a second heat source temperature sensor 34 is provided in the heat source supply path 18 between the evaporator 15 and the waste heat recovery heat exchanger 17. .

次に、本実施例の給水加温システム１の制御（運転方法）について説明する。以下に説明する一連の制御は、図示しない制御器を用いて自動でなされる。 Next, control (operation method) of the feed water heating system 1 of the present embodiment will be described. A series of control described below is automatically performed using a controller (not shown).

給水タンク３には、給水路８を介して給水可能であると共に補給水路９を介しても給水可能であるが、後述の（４）の場合を除き、通常は、給水路８を介した給水が優先されるように制御されるのが好ましい。たとえば、給水タンク３の水位を設定範囲に維持するように、給水路８を介した給水を制御するが、それでは給水タンク３の水位が設定範囲を維持できない場合には、補給水路９を介しても給水タンク３へ給水するのが好ましい。 The water supply tank 3 can be supplied with water through the water supply channel 8 and can also be supplied with water through the replenishment water channel 9, but normally water supply through the water supply channel 8 except in the case of (4) described later. Is preferably controlled so as to be prioritized. For example, the water supply through the water supply channel 8 is controlled so as to maintain the water level of the water supply tank 3 within the set range. However, if the water level of the water supply tank 3 cannot be maintained within the set range, It is preferable to supply water to the water supply tank 3.

具体的には、本実施例では、次のように制御される。いま、給水停止電極棒２８が水位を検知し、給水タンク３の水位が十分にある場合、給水タンク３への給水は不要であるから、給水ポンプ１０を停止すると共に、補給水ポンプ１１も停止している。給水タンク３からボイラ２への給水により、給水タンク３の水位が下がり、給水開始電極棒２９が水位を検知しなくなると、給水ポンプ１０を作動させる。これにより、給水路８を介して給水タンク３に給水されるが、給水停止電極棒２８が水位を検知すると、給水ポンプ１０を停止する。一方、給水ポンプ１０を作動させても、給水タンク３の水位を回復できず、さらに低い所定の補給水開始水位を下回ると、補給水ポンプ１１を作動させて、補給水路９を介しても給水タンク３に給水する。これにより、給水タンク３の水位が回復して、給水タンク３の水位が補給水停止水位を上回ると、補給水ポンプ１１を停止して、補給水路９を介しての給水を停止する。なお、給水ポンプ１０を作動させて、給水路８を介した給水タンク３への給水中、熱源供給ポンプ２４も作動させる。 Specifically, in this embodiment, control is performed as follows. Now, when the water supply stop electrode rod 28 detects the water level and the water level in the water supply tank 3 is sufficient, the water supply to the water supply tank 3 is unnecessary, so the water supply pump 10 is stopped and the makeup water pump 11 is also stopped. doing. When the water level in the water supply tank 3 drops due to the water supply from the water supply tank 3 to the boiler 2 and the water supply start electrode rod 29 no longer detects the water level, the water supply pump 10 is activated. Thereby, water is supplied to the water supply tank 3 through the water supply path 8, but when the water supply stop electrode rod 28 detects the water level, the water supply pump 10 is stopped. On the other hand, even if the water supply pump 10 is operated, the water level in the water supply tank 3 cannot be recovered, and when the water supply level falls below a predetermined lower supply water start level, the water supply pump 11 is operated to supply water through the supply water channel 9. Supply water to tank 3. Thereby, when the water level of the water supply tank 3 recovers and the water level of the water supply tank 3 exceeds the makeup water stop water level, the makeup water pump 11 is stopped and the water supply via the makeup water channel 9 is stopped. In addition, the water supply pump 10 is operated, and the water supply to the water supply tank 3 through the water supply path 8 and the heat source supply pump 24 are also operated.

ヒートポンプ４は、後述するように、所定の場合に作動する。ヒートポンプ４は、その圧縮機１２の作動の有無により、運転と停止が切り替えられる。また、本実施例では、ヒートポンプ４は、高負荷運転（典型的には全負荷運転＝１００％出力）、低負荷運転（たとえば５０％出力）および停止（０％出力）の三位置で制御される。 As will be described later, the heat pump 4 operates in a predetermined case. The heat pump 4 is switched between operation and stop depending on whether or not the compressor 12 is activated. In this embodiment, the heat pump 4 is controlled at three positions: high load operation (typically full load operation = 100% output), low load operation (for example, 50% output), and stop (0% output). The

給水ポンプ１０は、作動中、出湯温度センサ２５の検出温度を設定温度（出湯温度設定値）Ｔ０に維持するように、回転数をインバータ制御される。その結果、ヒートポンプ４の高負荷運転時は低負荷運転時よりも多い流量で、給水路８を介して給水タンク３へ給水可能となる。 During operation, the feed water pump 10 is inverter-controlled so that the temperature detected by the tapping temperature sensor 25 is maintained at a set temperature (tapping temperature setting value) T0. As a result, it is possible to supply water to the water supply tank 3 through the water supply path 8 at a higher flow rate during high load operation of the heat pump 4 than during low load operation.

制御器は、出湯温度設定値Ｔ０の他、第一熱源温度センサ３３による蒸発器１５入口側の熱源水温度Ｔ１、給水温度センサ２６による新水温度（廃熱回収熱交換器１７やヒートポンプ４で加温する前の水温）ＴＷ、さらに所望により、第二熱源温度センサに３４よる蒸発器１５出口側の熱源水温度Ｔ２を監視して、以下のとおり場合分けして制御する。 In addition to the tapping temperature set value T0, the controller includes a heat source water temperature T1 on the evaporator 15 inlet side by the first heat source temperature sensor 33, a new water temperature by the feed water temperature sensor 26 (waste heat recovery heat exchanger 17 and heat pump 4). Water temperature before heating) TW and, if desired, the heat source water temperature T2 on the outlet side of the evaporator 15 by the second heat source temperature sensor 34 are monitored and controlled according to the following cases.

《（１）蒸発器入口側の熱源水温度Ｔ１≧出湯温度設定値Ｔ０である場合》
蒸発器１５入口側の熱源水温度Ｔ１が出湯温度設定値Ｔ０以上である場合、給水路８を介した給水タンク３への給水中、圧縮機１２を停止すると共に、給水タンク３への給水を廃熱回収熱交換器１７に通す。つまり、ヒートポンプ４を停止した状態で、給水ポンプ１０と熱源供給ポンプ２４とを作動させて、廃熱回収熱交換器１７において、給水路８の給水を熱源水と熱交換して加温する。 << (1) When the heat source water temperature T1 on the evaporator inlet side is equal to or higher than the tapping temperature setting value T0 >>
When the heat source water temperature T1 on the evaporator 15 inlet side is equal to or higher than the tapping temperature set value T0, the compressor 12 is stopped while supplying water to the water supply tank 3 via the water supply path 8, and water supply to the water supply tank 3 is stopped. Pass through waste heat recovery heat exchanger 17. That is, in a state where the heat pump 4 is stopped, the water supply pump 10 and the heat source supply pump 24 are operated, and in the waste heat recovery heat exchanger 17, the water supply in the water supply path 8 is heat-exchanged with the heat source water and heated.

《（２）蒸発器入口側の熱源水温度Ｔ１＜出湯温度設定値Ｔ０、且つ、新水温度ＴＷ≦蒸発器出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）である場合》
蒸発器１５入口側の熱源水温度Ｔ１が出湯温度設定値Ｔ０未満である場合、給水路８を介した給水タンク３への給水中、圧縮機１２を運転する。そして、廃熱回収熱交換器１７の入口側水温ＴＷが蒸発器１５出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）以下の場合、給水タンク３への給水を廃熱回収熱交換器１７に通す。つまり、ヒートポンプ４を運転した状態で、給水路８を介した給水タンク３への給水は、廃熱回収熱交換器１７、過冷却器１６および凝縮器１３を順に通される。 << (2) When the heat source water temperature T1 on the evaporator inlet side <the tapping temperature setting value T0 and the new water temperature TW≤the heat source water temperature T2 (or T1) on the evaporator outlet side (or inlet side) >>
When the heat source water temperature T1 on the inlet side of the evaporator 15 is lower than the tapping temperature set value T0, the compressor 12 is operated while supplying water to the water supply tank 3 via the water supply path 8. When the inlet side water temperature TW of the waste heat recovery heat exchanger 17 is equal to or lower than the heat source water temperature T2 (or T1) on the outlet side (or inlet side) of the evaporator 15, the water supplied to the water supply tank 3 is subjected to waste heat recovery heat exchange. Pass through vessel 17. That is, in a state where the heat pump 4 is operated, water supplied to the water supply tank 3 through the water supply passage 8 is passed through the waste heat recovery heat exchanger 17, the supercooler 16, and the condenser 13 in order.

この際、ヒートポンプ４は、給水タンク３の水位に基づき出力を制御されるのがよい。本実施例では、給水タンク３の水位が下がり、給水開始電極棒２９が水位を検知しなくなると、ヒートポンプ４を低負荷運転し、それでも水位が回復せず、負荷切替電極棒３０が水位を検知しなくなると、ヒートポンプ４を高負荷運転に切り替える。そして、水位回復時には、給水開始電極棒２９が水位を検知すれば、ヒートポンプ４を低負荷運転に切り替え、給水停止電極棒２８が水位を検知すれば、ヒートポンプ４を停止させる。 At this time, the output of the heat pump 4 is preferably controlled based on the water level of the water supply tank 3. In this embodiment, when the water level in the water supply tank 3 falls and the water supply start electrode rod 29 no longer detects the water level, the heat pump 4 is operated at a low load, and the water level is not recovered yet, and the load switching electrode rod 30 detects the water level. If not, the heat pump 4 is switched to high load operation. At the time of water level recovery, if the water supply start electrode rod 29 detects the water level, the heat pump 4 is switched to low load operation, and if the water supply stop electrode rod 28 detects the water level, the heat pump 4 is stopped.

ヒートポンプ４を運転して、補給水タンク５から給水路８を介して給水タンク３へ給水する際、補給水タンク５からの給水は、廃熱回収熱交換器１７、過冷却器１６および凝縮器１３により徐々に加温されて、所定温度で給水タンク３へ供給される。給水タンク３とヒートポンプ４（凝縮器１３）との間で水を循環させる場合と比較して、補給水タンク５から給水タンク３への一回の通過（ワンススルー）で給水を加温するので、ヒートポンプ４を通過する前後の給水の温度差を確保して、ヒートポンプ４の成績係数（ＣＯＰ）の向上を図ることができる。また、各熱交換器をコンパクトに構成することもできる。 When the heat pump 4 is operated to supply water from the make-up water tank 5 to the water supply tank 3 via the water supply path 8, the water supplied from the make-up water tank 5 is used as the waste heat recovery heat exchanger 17, the supercooler 16, and the condenser. 13 is gradually heated and supplied to the water supply tank 3 at a predetermined temperature. Compared with the case where water is circulated between the water supply tank 3 and the heat pump 4 (condenser 13), the water supply is heated by a single pass (once through) from the makeup water tank 5 to the water supply tank 3. The temperature difference of the feed water before and after passing through the heat pump 4 can be secured, and the coefficient of performance (COP) of the heat pump 4 can be improved. Moreover, each heat exchanger can also be comprised compactly.

また、ヒートポンプ４の運転中、つまり給水路８を介した給水タンク３への給水中、熱源水タンク６の水温を第一熱源温度センサ３３で監視して、その温度に基づきヒートポンプ４の出力を調整してもよい。ヒートポンプ４の熱源としての熱源水の温度が高温なほど、ヒートポンプ４の出力を下げることができる。熱源水の温度を考慮してヒートポンプ４の出力を調整することで、熱源水の温度変化に拘わらず、給水路８を介した給水タンク３への給水流量を安定させることができる。 Further, during operation of the heat pump 4, that is, water supply to the water supply tank 3 via the water supply path 8, the water temperature of the heat source water tank 6 is monitored by the first heat source temperature sensor 33, and the output of the heat pump 4 is based on the temperature. You may adjust. The higher the temperature of the heat source water as the heat source of the heat pump 4, the lower the output of the heat pump 4. By adjusting the output of the heat pump 4 in consideration of the temperature of the heat source water, the water supply flow rate to the water supply tank 3 via the water supply path 8 can be stabilized regardless of the temperature change of the heat source water.

さらに、ヒートポンプ４の運転中、熱源水タンク６の水位が下がり、低水位検出電極棒３２が水位を検知しなくなると、ヒートポンプ４の運転を停止すると共に、熱源供給ポンプ２４を停止して蒸発器１５への熱源水の供給を停止するのがよい。これにより、ヒートポンプ４を無駄に運転するのが防止される。また、同様に、ヒートポンプ４の運転中（つまり給水路８を介した給水タンク３への給水制御中）、万一、給水路８を通る給水の量が設定を下回ると、ヒートポンプ４の運転を停止すると共に、熱源供給ポンプ２４を停止して蒸発器１５への熱源水の供給を停止するのがよい。 Further, when the water level of the heat source water tank 6 is lowered during the operation of the heat pump 4 and the low water level detection electrode bar 32 no longer detects the water level, the operation of the heat pump 4 is stopped and the heat source supply pump 24 is stopped and the evaporator The supply of heat source water to 15 may be stopped. This prevents the heat pump 4 from being wasted. Similarly, during operation of the heat pump 4 (that is, during water supply control to the water supply tank 3 through the water supply path 8), if the amount of water supplied through the water supply path 8 falls below the setting, the operation of the heat pump 4 is stopped. While stopping, it is preferable to stop the supply of heat source water to the evaporator 15 by stopping the heat source supply pump 24.

《（３）蒸発器入口側の熱源水温度Ｔ１＜出湯温度設定値Ｔ０、且つ、新水温度ＴＷ＞蒸発器出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）である場合》
蒸発器１５入口側の熱源水温度Ｔ１が出湯温度設定値Ｔ０未満である場合、給水路８を介した給水タンク３への給水中、圧縮機１２を運転する。そして、廃熱回収熱交換器１７の入口側水温ＴＷが蒸発器１５出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）を超える場合、給水タンク３への給水を廃熱回収熱交換器１７に通さずに、バイパス路１９を介して過冷却器１６へ供給する。これにより、廃熱回収熱交換器１７において、給水が熱源水により逆に冷やされるという不都合を防止することができる。なお、この（３）の場合も、前記（２）の場合と同様に、ヒートポンプ４は、給水タンク３の水位に基づき出力を制御されるのがよい。 << (3) Case where Heat Source Water Temperature T1 on the Evaporator Inlet Side <Tapped Water Temperature Set Value T0 and New Water Temperature TW> Heat Source Water Temperature T2 (or T1) on the Evaporator Outlet Side (or Inlet Side) >>
When the heat source water temperature T1 on the inlet side of the evaporator 15 is lower than the tapping temperature set value T0, the compressor 12 is operated while supplying water to the water supply tank 3 via the water supply path 8. When the inlet side water temperature TW of the waste heat recovery heat exchanger 17 exceeds the heat source water temperature T2 (or T1) on the outlet side (or inlet side) of the evaporator 15, the water supplied to the water supply tank 3 is subjected to waste heat recovery heat exchange. The refrigerant is supplied to the supercooler 16 through the bypass 19 without passing through the condenser 17. Thereby, in the waste heat recovery heat exchanger 17, it is possible to prevent the disadvantage that the feed water is cooled by the heat source water. In the case of (3), as in the case of (2), the output of the heat pump 4 is preferably controlled based on the water level of the water supply tank 3.

《（４）新水温度ＴＷ≧出湯温度設定値Ｔ０の場合》
廃熱回収熱交換器１７の入口側水温ＴＷが出湯温度設定値Ｔ０以上である場合、圧縮機１２を停止すると共に、給水路８を介した給水タンク３への給水を停止する。そして、給水タンク３の水位に基づき、補給水ポンプ１１を制御して、補給水路９を介した給水タンク３への給水を制御する。給水源の温度が高いので、ヒートポンプ４や廃熱回収熱交換器１７を用いずに、補給水路９により給水タンク３へ給水すれば足りることになる。 << (4) When the fresh water temperature TW ≧ the tapping temperature set value T0 >>
When the inlet side water temperature TW of the waste heat recovery heat exchanger 17 is equal to or higher than the tapping temperature set value T0, the compressor 12 is stopped and the water supply to the water supply tank 3 via the water supply path 8 is stopped. Based on the water level of the water supply tank 3, the makeup water pump 11 is controlled to control the water supply to the water supply tank 3 via the makeup water channel 9. Since the temperature of the water supply source is high, it is sufficient to supply water to the water supply tank 3 through the makeup water channel 9 without using the heat pump 4 or the waste heat recovery heat exchanger 17.

本実施例２の給水加温システム１も、基本的には前記実施例１と同様である。そこで、以下においては、両者の異なる点を中心に説明し、図１に基づき、対応する箇所には同一の符号を用いて説明する。 The feed water heating system 1 of the second embodiment is basically the same as that of the first embodiment. Therefore, in the following, the differences between the two will be mainly described, and the same reference numerals will be used for corresponding portions based on FIG.

本実施例２でも、給水タンク３の水位に基づき、給水路８を介した給水タンク３への給水が制御される。但し、前記実施例１では、給水ポンプ１０による流量は、凝縮器１３の出口側水温を設定温度Ｔ０に維持するように制御されたが、本実施例２では、給水タンク３の水位に基づき制御される。ここでは、給水タンク３の水位が下がるほど、給水路８を介した給水流量が増すように、給水ポンプ１０がインバータ制御される。たとえば、給水タンク３に設けた水位検出器２７により、給水ポンプ１０による給水流量を段階的に切り替えればよい。 Also in the second embodiment, water supply to the water supply tank 3 via the water supply path 8 is controlled based on the water level of the water supply tank 3. However, in the first embodiment, the flow rate by the feed water pump 10 is controlled so as to maintain the outlet water temperature of the condenser 13 at the set temperature T0, but in the second embodiment, the flow rate is controlled based on the water level of the feed water tank 3. Is done. Here, the feed water pump 10 is inverter-controlled so that the feed water flow rate through the feed water path 8 increases as the water level in the feed water tank 3 decreases. For example, the water supply flow rate by the water supply pump 10 may be switched stepwise by the water level detector 27 provided in the water supply tank 3.

一方、ヒートポンプ４の圧縮機１２は、前記実施例１では、給水タンク３の水位に基づき出力を調整されたが、本実施例２では、吐出圧を設定値に維持するように、インバータ制御される。つまり、ヒートポンプ４には、圧縮機１２の出口側に、冷媒圧力を検出する圧力センサ３５が設けられており、この圧力センサ３５の検出圧力を設定値に維持するように、圧縮機１２のモータの電源周波数をインバータにより変えることで、出力が調整される。なお、圧力センサ３５に代えて温度センサを設け、圧縮機１２の出口側の温度を設定値に維持するように制御してもよい。 On the other hand, the compressor 12 of the heat pump 4 has its output adjusted based on the water level of the water supply tank 3 in the first embodiment, but in this second embodiment, it is controlled by an inverter so as to maintain the discharge pressure at a set value. The That is, the heat pump 4 is provided with a pressure sensor 35 that detects the refrigerant pressure on the outlet side of the compressor 12, and the motor of the compressor 12 is maintained so that the detected pressure of the pressure sensor 35 is maintained at a set value. The output is adjusted by changing the power frequency of the inverter with an inverter. A temperature sensor may be provided in place of the pressure sensor 35, and control may be performed so that the temperature on the outlet side of the compressor 12 is maintained at a set value.

このような制御中、基本的には、給水タンク３への給水は、廃熱回収熱交換器１７、過冷却器１６および凝縮器１３を通される。但し、給水路８の給水流量が設定流量以下になると、三方弁２０を切り替えて、給水タンク３への給水を廃熱回収熱交換器１７には通さない。これにより、凝縮器１３における熱交換量を増やし、圧縮機１２の停止を防止することができる。 During such control, basically, water supplied to the water supply tank 3 is passed through the waste heat recovery heat exchanger 17, the subcooler 16, and the condenser 13. However, when the water supply flow rate in the water supply path 8 is equal to or lower than the set flow rate, the three-way valve 20 is switched so that the water supply to the water supply tank 3 is not passed through the waste heat recovery heat exchanger 17. Thereby, the amount of heat exchange in the condenser 13 can be increased, and the stop of the compressor 12 can be prevented.

ところで、給水路８による給水流量は、圧縮機１２を吐出圧に基づきインバータ制御する場合、圧縮機１２へのモータの電源周波数と相関する。従って、周波数が設定周波数以下になると、給水タンク３への給水を廃熱回収熱交換器１７には通さずにバイパス路１９を通しての給水に切り替えるよう制御してもよい。 By the way, the feed water flow rate by the feed water path 8 correlates with the power supply frequency of the motor to the compressor 12 when the compressor 12 is inverter-controlled based on the discharge pressure. Therefore, when the frequency becomes equal to or lower than the set frequency, the water supply to the water supply tank 3 may be controlled to be switched to the water supply through the bypass 19 without passing through the waste heat recovery heat exchanger 17.

本実施例２でも、前記実施例１と同様に、廃熱回収熱交換器１７の入口側水温ＴＷが蒸発器１５出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）以下の場合、給水路８を介した給水タンク３への給水中、給水タンク３への給水を廃熱回収熱交換器１７に通せばよい。また、廃熱回収熱交換器１７の入口側水温ＴＷが蒸発器１５出口側（または入口側）の熱源水温度Ｔ２（またはＴ１）を超える場合、給水タンク３への給水を廃熱回収熱交換器１７に通さずに、バイパス路１９を介して過冷却器１６へ供給すればよい。その他の構成は、前記実施例１と同様であるため、説明は省略する。 Also in the second embodiment, as in the first embodiment, when the inlet side water temperature TW of the waste heat recovery heat exchanger 17 is equal to or lower than the heat source water temperature T2 (or T1) on the outlet side (or inlet side) of the evaporator 15, The water supply to the water supply tank 3 via the water supply path 8 and the water supply to the water supply tank 3 may be passed through the waste heat recovery heat exchanger 17. Further, when the water temperature TW at the inlet side of the waste heat recovery heat exchanger 17 exceeds the heat source water temperature T2 (or T1) at the outlet side (or inlet side) of the evaporator 15, the water supplied to the water supply tank 3 is subjected to waste heat recovery heat exchange. What is necessary is just to supply to the supercooler 16 via the bypass path 19, without letting it pass through the vessel 17. Since other configurations are the same as those of the first embodiment, description thereof is omitted.

本発明の給水加温システム１は、前記実施例の構成に限らず、適宜変更可能である。たとえば、前記実施例では、給水路８を介した給水タンク３への給水流量を調整するために、給水ポンプ１０をインバータ制御したが、給水ポンプ１０をオンオフ制御しつつ、給水路８に設けたバルブの開度を調整してもよい。つまり、出湯温度センサ２５の検出温度などに基づき給水路８を介した給水の流量を調整可能であれば、その流量調整方法は適宜に変更可能である。 The feed water warming system 1 of the present invention is not limited to the configuration of the above embodiment, and can be changed as appropriate. For example, in the said Example, in order to adjust the feed water flow rate to the feed water tank 3 via the feed water path 8, the feed water pump 10 was inverter-controlled, However, The feed water pump 10 was provided in the feed water path 8 while performing on-off control. The opening degree of the valve may be adjusted. That is, if the flow rate of the water supply through the water supply path 8 can be adjusted based on the temperature detected by the hot water temperature sensor 25, the flow rate adjustment method can be changed as appropriate.

また、ヒートポンプ４は、単段に限らず複数段とすることもできる。ヒートポンプ４を複数段にする場合、隣接する段のヒートポンプ同士は、間接熱交換器を用いて接続されてもよいし、直接熱交換器（中間冷却器）を用いて接続されてもよい。後者の場合、下段ヒートポンプの圧縮機からの冷媒と上段ヒートポンプの膨張弁からの冷媒とを受けて、両冷媒を直接に接触させて熱交換する中間冷却器を備え、この中間冷却器が下段ヒートポンプの凝縮器であると共に上段ヒートポンプの蒸発器とされる。このように、複数段（多段）のヒートポンプには、一元多段のヒートポンプの他、複数元（多元）のヒートポンプ、あるいはそれらの組合せのヒートポンプが含まれる。 Further, the heat pump 4 is not limited to a single stage, and may be a plurality of stages. When the heat pump 4 has a plurality of stages, adjacent stage heat pumps may be connected using an indirect heat exchanger, or may be connected using a direct heat exchanger (intercooler). In the latter case, an intermediate cooler that receives the refrigerant from the compressor of the lower heat pump and the refrigerant from the expansion valve of the upper heat pump and directly exchanges heat between the two refrigerants is provided. And the evaporator of the upper heat pump. As described above, the multi-stage (multi-stage) heat pump includes a single-stage multi-stage heat pump, a multi-element (multi-element) heat pump, or a combination thereof.

また、給水タンク３に、凝縮器１３を介して給水路８により給水可能であると共に、凝縮器１３を介さずに補給水路９により給水可能であれば、給水路８や補給水路９の具体的構成は、前記実施例の構成に限らず適宜変更可能である。たとえば、前記実施例では、給水路８と補給水路９とは、それぞれ補給水タンク５と給水タンク３とを接続するように並列に設けたが、給水路８と補給水路９との一端部（補給水タンク５側の端部）と他端部（給水タンク３側の端部）の一方または双方は、共通の管路としてもよい。言い換えれば、補給水路９の一端部は、補給水タンク５に接続するのではなく、給水路８から分岐するように設けてもよいし、補給水路９の他端部は、給水タンク３に接続するのではなく、給水タンク３の手前において給水路８に合流するように設けてもよい。補給水路９の一端部を、補給水タンク５に接続するのではなく、給水路８から分岐するように設ける場合、その分岐部より下流において、給水路８に給水ポンプ１０を設ける一方、補給水路９に補給水ポンプ１１を設ければよいが、分岐部よりも上流側の共通管路にのみポンプを設けて、分岐部より下流の給水路８および／または補給水路９に設けたバルブの開度を調整することで、給水路８や補給水路９を通る流量を調整してもよい。 In addition, if water can be supplied to the water supply tank 3 through the water supply path 8 via the condenser 13 and water can be supplied through the replenishment water path 9 without going through the condenser 13, the specifics of the water supply path 8 and the replenishment water path 9 are specified. The configuration is not limited to the configuration of the above embodiment and can be changed as appropriate. For example, in the above-described embodiment, the water supply channel 8 and the supply water channel 9 are provided in parallel so as to connect the supply water tank 5 and the water supply tank 3, respectively, but one end portion of the water supply channel 8 and the supply water channel 9 ( One or both of the end portion on the make-up water tank 5 side and the other end portion (the end portion on the water supply tank 3 side) may be a common conduit. In other words, one end of the makeup water channel 9 may be provided so as to branch from the water supply channel 8 instead of being connected to the makeup water tank 5, and the other end of the makeup water channel 9 is connected to the water supply tank 3. Instead, it may be provided so as to join the water supply path 8 before the water supply tank 3. When one end portion of the replenishment water channel 9 is provided so as to branch from the water supply channel 8 instead of being connected to the replenishment water tank 5, the water supply pump 10 is provided in the water supply channel 8 downstream from the branching unit, while the replenishment water channel 9 may be provided with a supplementary water pump 11, but a pump is provided only in the common pipe upstream of the branching portion, and the valves provided in the water supply passage 8 and / or the supplementary waterway 9 downstream of the branching portion are opened. By adjusting the degree, the flow rate through the water supply channel 8 and the replenishment channel 9 may be adjusted.

また、前記実施例では、給水タンク３への給水を貯留するために補給水タンク５を設置したが、場合により補給水タンク５の設置を省略して、給水源から直接に給水路８および補給水路９に水を通してもよい。 Moreover, in the said Example, although the supplementary water tank 5 was installed in order to store the water supply to the water supply tank 3, installation of the supplementary water tank 5 may be abbreviate | omitted by the case, and the water supply path 8 and the supplement may be directly from a water supply source. Water may be passed through the water channel 9.

また、前記実施例では、給水路８および／または補給水路９を介して、補給水タンク５から給水タンク３へ給水可能としたが、これら給水は、軟水器から直接に行ってもよい。たとえば、図１において、給水路８および補給水路９の基端部をまとめて軟水器に接続し、給水ポンプ１０の設置を省略する代わりに給水路８に設けた電動弁（モータバルブ）の開度を調整し、補給水ポンプ１１の設置を省略する代わりに補給水路９に設けた電磁弁の開閉を制御すればよい。 Moreover, in the said Example, although it was made possible to supply water from the makeup water tank 5 to the water supply tank 3 via the water supply channel 8 and / or the makeup water channel 9, these water supply may be performed directly from a water softener. For example, in FIG. 1, instead of omitting the installation of the water supply pump 10 by connecting the base ends of the water supply channel 8 and the makeup water channel 9 together to the water softener, the opening of an electric valve (motor valve) provided in the water supply channel 8 Instead of adjusting the degree and omitting the installation of the makeup water pump 11, the opening and closing of the electromagnetic valve provided in the makeup water channel 9 may be controlled.

また、前記実施例では、ボイラ２の給水タンク３への給水をヒートポンプ４で加温できるシステムについて説明したが、給水タンク３の貯留水の利用先は、ボイラ２に限らず適宜に変更可能である。そして、場合により、補給水タンク５や補給水路９を省略してもよい。 Moreover, although the said Example demonstrated the system which can heat the water supply to the feed water tank 3 of the boiler 2 with the heat pump 4, the utilization place of the stored water of the feed water tank 3 is not restricted to the boiler 2, and can be changed suitably. is there. In some cases, the replenishment water tank 5 and the replenishment water channel 9 may be omitted.

また、前記実施例では、ヒートポンプ４の熱源として熱源水を用いた例について説明したが、ヒートポンプ４の熱源流体として、熱源水に限らず、空気や排ガスなど各種の流体を用いることができる。但し、熱源流体は、蒸発器１５においてヒートポンプ４の冷媒に熱（顕熱）を与えつつ自身は温度低下を伴い、その後、廃熱回収熱交換器１７において給水に熱（顕熱）を与えつつ自身は温度低下を伴う流体が好ましい。 Moreover, although the said Example demonstrated the example using heat-source water as a heat source of the heat pump 4, as a heat-source fluid of the heat pump 4, not only heat-source water but various fluids, such as air and waste gas, can be used. However, while the heat source fluid gives heat (sensible heat) to the refrigerant of the heat pump 4 in the evaporator 15, the heat source fluid itself falls in temperature, and then gives heat (sensible heat) to the feed water in the waste heat recovery heat exchanger 17. The fluid itself with a temperature drop is preferable.

さらに、前記実施例では、ヒートポンプ４の圧縮機１２は、電気モータにより駆動されたが、圧縮機１２の駆動源は特に問わない。たとえば、圧縮機１２は、電気モータに代えてまたはそれに加えて、蒸気を用いて動力を起こすスチームモータ（蒸気エンジン）に駆動されたり、ガスエンジンにより駆動されたりしてもよい。 Furthermore, in the said Example, although the compressor 12 of the heat pump 4 was driven by the electric motor, the drive source of the compressor 12 is not ask | required in particular. For example, the compressor 12 may be driven by a steam motor (steam engine) that generates power using steam instead of or in addition to the electric motor, or may be driven by a gas engine.

１給水加温システム
３給水タンク
４ヒートポンプ
５補給水タンク
６熱源水タンク
８給水路
９補給水路
１０給水ポンプ
１１補給水ポンプ
１２圧縮機
１３凝縮器
１４膨張弁
１５蒸発器
１６過冷却器
１７廃熱回収熱交換器
１９バイパス路
２０三方弁
２５出湯温度センサ
２６給水温度センサ
２７水位検出器
３３第一熱源温度センサ
３４第二熱源温度センサ
３５圧力センサ DESCRIPTION OF SYMBOLS 1 Supply water heating system 3 Supply water tank 4 Heat pump 5 Supply water tank 6 Heat source water tank 8 Supply water path 9 Supply water path 10 Supply water pump 11 Supply water pump 12 Compressor 13 Condenser 14 Expansion valve 15 Evaporator 16 Supercooler 17 Waste heat Recovery heat exchanger 19 Bypass path 20 Three-way valve 25 Hot water temperature sensor 26 Feed water temperature sensor 27 Water level detector 33 First heat source temperature sensor 34 Second heat source temperature sensor 35 Pressure sensor

Claims

A compressor, a condenser, an expansion valve, and an evaporator are sequentially connected in an annular manner to circulate the refrigerant, draw up heat from a heat source fluid that passes through the evaporator, and heat water that passes through the condenser When,
A waste water recovery heat exchanger, a supercooler, and a water supply tank capable of supplying water through a water supply passage through the condenser in order,
The waste heat recovery heat exchanger is an indirect heat exchanger between the water supply to the water supply tank via the water supply channel and the heat source fluid after passing through the evaporator,
The supercooler is an indirect heat exchanger between water supplied to the water supply tank via the water supply channel and refrigerant from the condenser to the expansion valve,
Switching between supplying water to the supercooler through the waste heat recovery heat exchanger and then supplying to the supercooler or supplying to the subcooler without passing through the waste heat recovery heat exchanger A water heating system characterized by being made possible.

Based on the water level of the water supply tank, controlling water supply to the water supply tank via the water supply channel,
During the water supply to the water supply tank via the water supply path, the water flow rate is adjusted so as to maintain the water temperature on the outlet side of the condenser at a set temperature,
When the heat source fluid temperature on the inlet side of the evaporator is equal to or higher than the set temperature, the compressor is stopped during water supply to the water supply tank via the water supply channel, and water supply to the water supply tank is discarded. The feed water heating system according to claim 1, wherein the feed water heating system is passed through a heat recovery heat exchanger.

When the heat source fluid temperature on the inlet side of the evaporator is lower than the set temperature, the compressor is operated during water supply to the water supply tank via the water supply path,
When the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or lower than the heat source fluid temperature on the outlet side or the inlet side of the evaporator, feed water to the water supply tank is passed through the waste heat recovery heat exchanger,
When the water temperature on the inlet side of the waste heat recovery heat exchanger exceeds the heat source fluid temperature on the outlet side or the inlet side of the evaporator, water supplied to the water supply tank is not passed through the waste heat recovery heat exchanger. The feed water heating system according to claim 2.

The water supply tank can be supplied with water from the same water supply source through the water supply channel, and can be supplied through the replenishment water channel without any of the waste heat recovery heat exchanger, the subcooler, and the condenser. And
When the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or higher than the set temperature, the compressor is stopped and the water supply to the water supply tank via the water supply channel is stopped, and the water supply tank The water supply heating system according to claim 2 or 3, wherein water supply to the water supply tank via the makeup water channel is controlled based on a water level.

Based on the water level of the water supply tank, controlling water supply to the water supply tank via the water supply channel,
2. The water supply system according to claim 1, wherein when the water supply flow rate to the water supply tank via the water supply channel becomes a set flow rate or less, the water supply to the water supply tank is not passed through the waste heat recovery heat exchanger. Temperature system.

The compressor is controlled in output by changing the power frequency of the motor with an inverter so as to maintain the discharge pressure at a set value.
The feed water heating system according to claim 1 or 5, wherein when the frequency becomes equal to or lower than a set frequency, feed water to the feed water tank is not passed through the waste heat recovery heat exchanger.

When the water temperature on the inlet side of the waste heat recovery heat exchanger is equal to or lower than the heat source fluid temperature on the outlet side of the evaporator, the water supply to the water supply tank and the water supply to the water supply tank via the water supply channel are discarded. Through heat recovery heat exchanger,
When the water temperature on the inlet side of the waste heat recovery heat exchanger exceeds the heat source fluid temperature on the outlet side of the evaporator, the water supply to the water supply tank and the water supply to the water supply tank via the water supply channel are discarded. The feed water warming system according to claim 5 or 6, wherein the feed water warming system is not passed through a heat recovery heat exchanger.