JP2010008016A - Hot water supply system and cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cogeneration system and a hot water supply system applied to the cogeneration system capable of filling a storage tank with water in a comparatively short time. <P>SOLUTION: In this cogeneration system 1 constituted by combining a power generator 2 incorporating a fuel cell, and a hot water supply system device 3, a hot water supply flow channel 30 is formed by a series of flow channels from the storage tank 10 to a faucet 34 through a combustion device 31, and a combustion device 31 (auxiliary heat source) is disposed on the way. An auxiliary heating going-water volume sensor is disposed in the flow channel from the storage tank 10 to the combustion device 31. In a tank water filling mode, water is supplied to the storage tank 10 from the water supply flow channel 30, and the tank water filling mode is terminated under a condition that the difference between the water volume detected by a water supply-side water volume sensor and the water volume detected by the auxiliary heating going-water volume sensor is smaller than a specific value as one of conditions. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hot water supply system that is connected to a heat / electricity generator capable of generating both electricity and heat, such as a fuel cell, and constitutes a cogeneration system. The present invention also relates to a cogeneration system.

  As disclosed in Patent Document 1 below, a cogeneration system including a heat recovery device that recovers thermal energy of exhaust heat generated in a power generation device such as a fuel cell through hot water and can be stored in a storage tank There is. The cogeneration system having such a configuration has a tank circulation channel through which hot water can circulate between the power generation device and the storage tank, and cools the power generation device with hot water circulating through the tank circulation channel. Along with this, the heated hot water is stored in a storage tank.

Moreover, in the cogeneration system described in Patent Document 1, a burner is mounted as an auxiliary heating device.
JP 2007-64526 A

  By the way, as a practical problem, the cogeneration system needs to be trial run in the factory or at the installation site. The cogeneration system disclosed in Patent Document 1 collects exhaust heat from a fuel cell or the like through hot water and stores the hot water in a storage tank. Normal operation cannot be performed unless the pipes and tanks are completely filled with water. For this reason, the cogeneration system must be shipped from the factory, installed at the place of use, then commissioned with water in the storage tank and piping, and then handed over to the user.

  The operation of filling the storage tank with water is performed by introducing water into the cogeneration system, for example, by an operator opening a hot water tap connected to the cogeneration system. In this case, water and bubbles are discharged from the hot water tap in a mixed state. Then, if air bubbles are not discharged from the hot water tap and only water is stably discharged, it is determined that all of the air in the storage tank has been replaced with water, and the water injection operation is finished.

  It is also conceivable that the water injection operation is completed by estimating that all of the air in the storage tank has been replaced with water by opening the hot-water tap for a certain period of time using a timer or the like.

As another method, it is conceivable to pay attention to the downstream water amount sensor among the water amount sensors in the cogeneration system and finish the water injection operation on the condition that the detected value of the water amount sensor is stable.
That is, if air remains in the storage tank, the amount of water discharged from the cogeneration system to the outside is not stable even if the amount of water supply is constant. Therefore, paying attention to the water amount sensor on the downstream side, the water injection operation is completed on condition that the detection value of the water amount sensor is stable.

However, all of the above-mentioned measures are uncertain because the criteria for determining whether or not the storage tank is filled with water are ambiguous. Therefore, the storage tank is more reliably filled with water, and water is poured into the storage tank for an excessively long time for safety.
Therefore, there is a problem that it takes a long time to pour water into the storage tank. There was also a complaint that a large amount of water had to be discarded.

In addition, water injection into the storage tank is performed only during trial operation or when equipment is installed, and is not a routine operation.
For this reason, providing a special sensor for confirming the completion of water injection to the storage tank is not a good measure in terms of equipment manufacturing costs.

  Accordingly, the present invention focuses on the above-described problems of the prior art, and can be used in cogeneration systems and cogeneration systems that can fill the storage tank with water in a relatively short time and do not require new sensors. An object is to provide a hot water supply system.

Therefore, the inventors examined a method of confirming completion of water injection using an existing sensor of the cogeneration system. Attention was paid to the water amount sensor provided in the flow path leading to the auxiliary heating device.
That is, the cogeneration system uses a device that generates both electricity and heat, such as a gas engine and a fuel cell, as the main heat source, creates hot water from the heat generated by this heat source, and stores this hot water in a storage tank as needed. Used. Therefore, when there is no hot water in the storage tank, when the hot water is insufficient, or when the temperature of the hot water is low, the hot water cannot be discharged.

Therefore, some cogeneration systems include an auxiliary heat source such as a burner in preparation for a hot water request when the hot water in the storage tank is insufficient. That is, when the hot water in the storage tank is not sufficient, the burner is ignited to make hot water, and the hot water is discharged in response to a hot water request.
In particular, in a cogeneration system whose main part is a fuel cell, an auxiliary heating device is essential.
That is, the fuel cell has a smaller calorific value than other heat / electricity generators such as a gas engine, and it takes time to raise the temperature of water. For this reason, when there is an unscheduled hot water request, hot water cannot be urgently produced only by the fuel cell. Therefore, as described above, in a cogeneration system having a fuel cell as a main part, an auxiliary heating device is indispensable, and it is no exaggeration to say that it is always installed.

Also, in the cogeneration system with the fuel cell as the main part, the temperature of the hot water stored in the storage tank is often relatively low, so a circuit configuration for taking out the hot water from the storage tank and supplying it to the auxiliary heating device Is often adopted.
Further, when hot water is supplied using a burner or the like as a heat source, it is necessary to control the hot water temperature to a temperature desired by the user. Here, in many cogeneration systems having a fuel cell as a main part, a method of determining the combustion amount based on the temperature and amount of hot water introduced into the auxiliary heating device and increasing or decreasing the combustion amount of the burner is adopted.

  The invention according to claim 1 completed based on these findings is a hot water supply system connected to a heat / electricity generator, and a storage tank for storing hot water heated by the heat / electricity generator, An auxiliary heating device, a water supply channel for supplying water to the storage tank, an auxiliary heating forward channel for supplying hot water discharged from the storage tank to the auxiliary heating device, and an auxiliary heating discharge channel for discharging from the auxiliary heating device In the hot water supply system, the hot water in the storage tank is discharged and consumed as needed, and the hot water in the storage tank is heated by an auxiliary heating device and then discharged and consumed as needed. A water supply side water volume sensor is provided, an auxiliary heating water flow sensor is provided in the auxiliary heating flow path, and a tank water injection mode for injecting water into the storage tank is provided as an operation mode. From the water supply side water amount sensor, the tank water injection mode ends, and a predetermined display is displayed on condition that the difference between the detected water amount of the water supply side water amount sensor and the detected water amount of the auxiliary heating forward water amount sensor is less than a certain value. A hot water supply system that performs at least one of stopping water supply to the storage tank.

Here, the predetermined display includes a visual display and an audible display, and notifies the completion of water injection.
In the hot water supply system of the present invention, the amount of water poured into the storage tank is detected by a water supply side water amount sensor, and the amount of water discharged from the storage tank is detected by an auxiliary heating forward water amount sensor. If the water in the storage tank is completely filled with water, the amount of water injected into the storage tank and the amount of water discharged from the storage tank should be the same. The water supply to the storage tank was stopped based on one of the conditions that the difference in the detected water volume of the outgoing water volume sensor was less than a certain level.

  The invention according to claim 2 has a flow path from the water supply flow path to the auxiliary heating forward flow path without passing through the storage tank and a flow path from the water supply flow path to the auxiliary heating discharge flow path without passing through the storage tank. Both of the flow paths are provided with valves, and the valve is closed, and the difference between the detected water amount of the water supply side water amount sensor and the detected water amount of the auxiliary heating forward water amount sensor is less than a certain value. The hot water supply system according to claim 1, wherein at least one of the end of the tank pouring mode, the predetermined display, and the stop of the water supply to the storage tank is executed under one of the conditions.

  The present invention has a flow path from the water supply flow path to the auxiliary heating forward flow path without passing through the storage tank, and a flow path from the water supply flow path to the auxiliary heating discharge flow path without passing through the storage tank. Compare the detected water volume of the water supply side water volume sensor and the detected water volume of the auxiliary heating water volume sensor with the flow path shut off. Therefore, it is possible to accurately know that the storage tank is filled with water.

  The invention described in claim 3 includes a post-mixing bypass flow channel that connects the water supply flow channel and the auxiliary heating / discharge channel, and water that flows through the post-mixing bypass channel to hot water that flows through the auxiliary heating / discharge channel. The temperature of hot water discharged after mixing can be adjusted, and a valve is provided in the post-mixing bypass flow path. In the tank water injection mode, the bypass water amount adjustment valve is closed to detect the water supply side water amount sensor. The hot water supply system according to claim 1 or 2, wherein the amount of water and the amount of water detected by an auxiliary heating forward water amount sensor are compared.

  Also in the present invention, since the after-mixing bypass flow path is closed and the inflow of water from the flow path is blocked, it can be accurately known that the storage tank is filled with water.

  According to a fourth aspect of the present invention, there is provided a premixing bypass flow channel that starts from the water supply flow channel and is connected between the storage tank and the water supply side water amount sensor, and the premixing bypass flow channel includes a valve. The hot water supply according to any one of claims 1 to 3, wherein in the tank water injection mode, the on-off valve is closed and the detected water amount of the water supply side water amount sensor is compared with the detected water amount of the auxiliary heating forward water amount sensor. System.

  Also in the present invention, since the premixing bypass flow path is closed and the inflow of water from the flow path is prevented, it can be accurately known that the storage tank is filled with water.

  According to a fifth aspect of the present invention, there is provided a tank circulation flow path that circulates between the heat / electricity generator and the storage tank, a tank bypass flow path that is connected to the tank circulation flow path and bypasses the storage tank, and the tank bypass A flow path switching means for switching between a flow path that circulates through the flow path and a flow path that circulates through the tank, and in the tank pouring mode, the flow path switching means is temporarily or always the heat / electricity generator. The hot water supply system according to any one of claims 1 to 4, wherein the three tanks, the storage tank and the tank-by-bass channel, are in communication with each other.

An object of the present invention is to inject water into another flow path simultaneously with water injection into the storage tank.
That is, in order to test run the cogeneration system, not only the storage tank but also other piping must be filled with water. However, the above-mentioned cogeneration system disclosed in Patent Document 1 has a problem that the air in the pipe is difficult to escape, the air in the pipe is replaced with water, and the time required to fill the pipe with water is long. . Specifically, it is difficult for the air in the tank bypass flow path to escape, and much time is required to replace the air in the tank bypass flow path with water.

Therefore, the present inventors examined the cause of the air in the tank bypass passage not being removed.
14 and 15 are operation principle diagrams of the main part showing a state when water is poured into the system in the conventional cogeneration system.
A cogeneration system 100 shown in FIGS. 14 and 15 includes a fuel cell device 101 as a heat / electricity generator and a hot water storage device as a hot water supply system. The fuel cell device 101 includes a fuel cell 102 and a circulation pump 103. Note that the fuel cell 102 has a heat exchanger and can pass water therein, and exhaust heat of the fuel cell 102 can be taken away by passing water inside.

The hot water storage device is centered on the storage tank 105 and includes a tank circulation channel 110. The tank circulation channel 110 is a channel that circulates in an annular shape including the fuel cell device 101 and the storage tank 105.
Specifically, the tank circulation flow path 110 includes a heating forward flow path 112 connecting the lower part of the storage tank 105 and the water inlet side of the fuel cell apparatus 101, a hot water outlet of the fuel cell apparatus 101, and an upper part of the storage tank 105. It is comprised by the heating return side flow path 113 to connect.
Further, there is a tank bypass channel 106 that connects the heating return side channel 113 and the heating forward channel 112 and bypasses the storage tank 105.

A three-way valve 115 is provided at a connection portion between the tank bypass channel 106 and the heating return side channel 113.
The three-way valve 115 has three ports a, b, and c as shown in FIG. 16, but is generally used in a state where a-b is opened or is used in a state where a-c is opened? And is not used at halfway opening positions.
That is, FIG. 16 is an explanatory view showing the structure of the three-way valve.

In the prior art, the same applies when water is poured into the system. Whether the three-way valve 115 is used in a state where a-b is opened or in a state where a-c is opened. It is either, and it is not used in the halfway opening position.
Here, in FIGS. 14 and 15, the ports painted black in the drawing of the three-way valve 115 indicate closed ports. Open ports indicate open ports. Thick lines and arrows indicate the flow of water.

As shown in FIG. 14, assuming that the three-way valve 115 is in a state where the fuel cell device 101 and the storage tank 105 are opened and the tank bypass channel 106 side is closed, water injection is introduced from the water supply channel 120, It flows into the storage tank 105 via the fuel cell device 101. When water injection is stopped and the circulation pump 103 is driven, water is passed through the tank circulation passage 110 including the fuel cell device 101 and the storage tank 105, and the air in the path is replaced with water.
However, in this case, since the port c on the tank bypass flow path 106 side of the three-way valve 115 is closed, water does not flow through the tank bypass flow path 106 and air in the tank bypass flow path 106 remains without being discharged. .

  On the other hand, as shown in FIG. 15, assuming that the three-way valve 115 is in a state where the space between the fuel cell device 101 and the tank bypass passage 106 is opened and the storage tank 105 side is closed, the three-way valve 115 is introduced from the water supply passage 120. Since the water discharge path is blocked by the b port of the three-way valve 115, water does not flow through the tank circulation path 110. Further, since the b port of the three-way valve 115 is blocked, there is no drainage path for the water that has entered the tank bypass channel 106, and no water flows through the tank bypass channel 106. Therefore, the air in the tank bypass channel 106 remains without being discharged.

  In addition, when water injection is stopped in this state and the circulation pump 103 is driven, water flows through the annular flow path constituted by the fuel cell device 101 and the tank bypass flow path 106, but this water simply circulates. Are not discharged to the outside. For this reason, the air in the tank bypass passage 106 circulates through the annular passage constituted by the fuel cell device 101 and the tank bypass passage 106, but the air does not go out of the system. Therefore, the air in the tank bypass channel 106 is dispersed to other parts, but the air still remains in the tank bypass channel 106.

  Therefore, the air in the tank bypass passage 106 does not escape from any direction of the communication of the three-way valve 115 after all. Therefore, in the prior art, the air in the pipe is difficult to escape, and it takes a long time to replace the air in the pipe with water and fill the pipe with water. In addition, in the water injection work, a lot of water was thrown away, and there was a problem of wasting water resources.

  Further, according to the experience of the present inventors, there was a case where an abnormal noise was felt when water was injected into a storage tank or piping. This abnormal noise is expected to be generated when the air in the tank bypass passage 106 escapes from a narrow gap such as the gap of the three-way valve 115.

Therefore, in the present invention, during the water injection operation, the three-way valve is set to a halfway opening state, and the ports a, b. It was decided that the water injection operation was performed in a state where c was in communication with each other.
17 and 18 are operation principle diagrams of the main part showing a state when water is poured into the system in the cogeneration system according to claim 5.
In the hot water supply system of the present invention, the channel switching means such as the three-way valve performs the water injection operation with the heat / electricity generator, the storage tank, and the tank bypass channel communicating with each other. A drainage path is formed, and water is generated in the tank bypass channel, and this water is discharged to the outside.
That is, as shown in FIG. 17, part of the water introduced from the water supply channel 120 flows into the storage tank 105 via the fuel cell device 101. Further, the remaining water introduced from the water supply channel 120 flows into the storage tank 105 via the tank bypass channel 106. Therefore, the air in the tank bypass flow path 106 passes into the storage tank 105, and the air in the tank bypass flow path 106 is replaced with water.

  When the water injection is stopped and the circulation pump 103 is driven, water is passed through the tank circulation passage 110 including the fuel cell device 101 and the storage tank 105 as shown in FIG. And goes around an annular flow path constituted by the fuel cell device 101 and the tank bypass flow path 106. However, as described above, part of the water also flows into the storage tank 105, so that the air in the tank bypass channel 106 circulates through the annular channel constituted by the fuel cell device 101 and the tank bypass channel 106. Inside, it goes out to the storage tank 105 side.

  A sixth aspect of the present invention is a cogeneration system in which a heat / electricity generator mainly including a fuel cell is connected to the hot water supply system according to any one of the first to fifth aspects.

  The cogeneration system of the present invention can produce electricity and hot water, and has high energy efficiency.

  INDUSTRIAL APPLICABILITY The hot water supply system and cogeneration system of the present invention can smoothly perform trial operation and water injection at the time of site installation, and have an effect of completing the trial operation and the like in a short time.

Next, a hot water supply system and a cogeneration system according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is an operation principle diagram showing a cogeneration system and a hot water supply system according to an embodiment of the present invention.
In FIG. 1, 1 is the cogeneration system of this embodiment. The cogeneration system 1 is roughly configured by combining a power generation device (heat / electricity generator) 2 and a hot water supply system device 3. The power generation device (heat / electricity generator) 2 and the hot water supply system device 3 are individually manufactured and connected by piping at the installation site to complete the cogeneration system 1.

The power generation device 2 is constituted by a fuel cell, and a heat generating unit 5 that generates heat accompanying power generation, and a heat exchanger 6 that cools the heat generating unit 5 and recovers exhaust heat generated during power generation. And. That is, the power generation apparatus 2 has both a function as a power generation device for supplying power to the power load E provided outside and a function as a thermal energy generation device for heating hot water.
In addition, a circulation pump 25 for allowing water to flow into the heat exchanger 6 is built in the power generator 2.

On the other hand, the hot water supply system device 3 is configured around a storage tank 10 for storing hot water. At the top of the storage tank 10, a hot water introduction side top connection portion 11 and a hot water discharge side top connection portion 14 are provided. Further, at the lower portion of the storage tank 10, a circulation channel bottom opening 12 and a water supply bottom opening 15 are provided.
And the piping which comprises the energy recovery system C and the hot-water supply / water supply system H is connected with respect to these hot-water supply side top connection parts 11, the hot-water discharge side top connection parts 14, the circulation channel bottom opening 12, and the water supply bottom opening 15. It has been configured.

  The storage tank 10 has a configuration in which a plurality of (four in this embodiment) temperature sensors 13a to 13d are attached in the height direction, that is, in the direction in which the level of hot water stored in the storage tank 10 increases. The temperature sensors 13a to 13d function as temperature detection means for detecting the temperature of the hot water in the storage tank 10, respectively, and the remaining amount for detecting the remaining amount of hot water in the storage tank 10 at a predetermined temperature or temperature range. Also serves as a quantity detection means.

  More specifically, in the cogeneration system 1 of the present embodiment, hot water taken out from the bottom of the storage tank 10 is discharged to the energy recovery system C and passes through the heat exchanging unit 6 of the power generation device 2 to exchange heat. It is configured to be heated and slowly returned to the top side of the storage tank 10.

Here, in general, when a liquid is stored in a tank, if the temperature difference between the liquids is equal to or greater than a predetermined threshold, the liquid is divided into layers for each temperature. That is, a temperature stratification is formed inside. For example, in hot water, the threshold is about 10 degrees Celsius (° C.).
Therefore, when the hot water passing through the energy recovery system C is heated to a temperature higher than the threshold temperature with respect to the temperature of the hot water in the storage tank 10 and slowly returned to the extent that the hot water in the storage tank 10 is not disturbed, Hot water stored in the storage tank 10 is divided into layers for each temperature. Therefore, it is possible to detect how much hot water heated to a desired temperature range is stored in the storage tank 10 by examining the detection temperatures of the temperature sensors 13 a to 13 d installed in the storage tank 10.

The energy recovery system C is formed by combining a plurality of pipes, bypasses the storage tank 10, and the tank circulation flow path 20 a that circulates between the power generation device (heating / electricity generator) 2 and the storage tank 10. A bypass circulation flow path 20b that passes through the tank bypass flow path 23 can be configured. More specifically, the energy recovery system C includes a heating forward flow path 21 that connects the circulation channel bottom opening 12 of the storage tank 10 and the heat exchanger 6 in the heat generating section 5, and a hot water introduction side top connection section. 11 and the heat return side flow path 22 which connects the heat exchanger 6. The heating forward side flow path 21 and the heating return side flow path 22 are connected to the power generation device 2 as shown in FIG. 1 to form a series of annular flow paths. Manual valves 16 and 17 are provided at the ends of the heating forward flow path 21 and the heating return flow path 22 so that the hot water supply system apparatus 3 can be separated from the hot water supply system apparatus 3.
In addition, the energy recovery system C includes a tank bypass flow path 23 that bypasses both flow paths at an intermediate portion between the heating forward flow path 21 and the heating return flow path 22. The tank bypass flow path 23 and the heating return side flow path 22 are connected via a three-way valve (flow path switching means) 28. The tank bypass channel 23 and the heating-out side channel 21 are connected via a tee 18.

  A heating forward flow path 21 shown on the lower side of the drawing is a flow path having a circulation flow path bottom opening 12 at the bottom of the storage tank 10 as a base end, and hot water discharged from the bottom side of the storage tank 10 This is a flow path that supplies the heat exchanger 6 of the heat generating unit 5. A tee 18 that branches the tank bypass passage 23 is provided in the middle of the heating-out passage 21.

  A temperature sensor 26 is provided in the middle of the heating-out side flow path 21 and downstream of the tee 18 in the hot water flow direction, that is, at a position on the power generation device 2 side. The temperature sensor 26 is provided to detect the temperature of hot water flowing in the energy recovery system C.

On the other hand, the heating return side flow path 22 shown on the upper side of the drawing is a flow path for returning the hot water that has passed through the heat exchanger 6 to the top side of the storage tank 10 (the hot water introduction side top connection part 11). The heating return side flow path 22 is divided into two systems in the middle, and is configured to join again on the downstream side. Specifically, the heating return side flow path 22 is branched into a heating branch flow path 60, which is a mainstream, and a bypass branch flow path 61, which is a bypass flow path. (Flow path switching means) 28 and the storage tank 10 are joined again.
The heating branch channel 60 is connected to the tank bypass channel 23 via a three-way valve (channel switching means) 28. A temperature sensor 27 is provided in the heating branch flow path 60.

The heating branch flow path 60 is connected to the heating system D constituted by the heating side circulation circuit 70 via the heat exchanger 71.
The bypass branch channel 61 is a channel that returns hot water from the heat generating unit 5 side to the storage tank 10 side without passing through the heat exchanger 71. An open / close valve 24 is provided in the bypass branch flow path 61.
Therefore, the hot water heated in the power generator 2 can be sent to the heat exchanger 71 side by closing the on-off valve 24.
When the on-off valve 24 is opened, most of the hot water heated in the power generator 2 is supplied to the storage tank 10 without passing through the heat exchanger 71.

FIG. 2 is a cross-sectional view showing the structure of the three-way valve, and FIGS. 2A, 2B, and 2C show cases where the postures of the valve bodies are different.
The above-described three-way valve (channel switching means) 28 is a three-way switching valve in which the valve body 62 rotates within a housing 59 having three openings (ports) a, b, and c as shown in FIG. Of the three ports a, b, and c constituting the three-way valve 28, two ports a and c are connected to the heating return channel 22 and the tank bypass channel 23 is connected to the remaining port b. ing. That is, the three-way valve 28 includes a passage on the storage tank 10 side of the heating return side passage 22 (hereinafter referred to as a heating return downstream passage 22a as necessary) and a three-way valve 28. Is also connected to a flow path on the power generation device 2 side (hereinafter referred to as a heating return upstream flow path 22b as necessary) and a tank bypass flow path 23.
The three-way valve (flow path switching means) 28 is equipped with a stepping motor (not shown), and the valve body 62 can be rotated by the stepping motor to stop the valve body 62 at an arbitrary position.

  The energy recovery system C can configure the tank circulation channel 20a and the bypass circulation channel 20b by adjusting the three-way valve 28 provided in the middle of the heating return side channel 22. More specifically, when the two ports connected to the heating return side flow path 22 among the three ports constituting the three-way valve 28 are opened, the storage tank 10 and the power generator as shown by hatching in FIG. The tank circulation flow path 20a in which hot water can circulate between the two can be configured. Moreover, when the fuel cell side port of the heating return side flow path 22 and the port connected to the tank bypass flow path 23 among the three ports constituting the three-way valve 28 are opened, storage is performed as shown by hatching in FIG. A bypass circulation channel 20b that can circulate hot water by bypassing the tank 10 can be formed.

  The heating system D includes a heating-side circulation circuit 70 for circulating a liquid such as antifreeze liquid between the heating terminal 65 installed outside the cogeneration system 1.

  The hot water supply / water supply system H includes a hot water supply passage 30 connected to the hot water introduction side top connection portion 14 of the storage tank 10 and a water supply flow for supplying hot water from the outside to the hot water supply passage 30 side and the energy recovery system C side. A path 50 is provided.

The hot water supply channel 30 forms a series of channels from the storage tank 10 through the combustion device 31 to the currant 34 or the bath dropping channel 66, and is provided with a combustion device (auxiliary heat source) 31 in the middle. It is said that.
In the present embodiment, the flow path from the storage tank 10 to the combustion apparatus 31 is referred to as an auxiliary heating forward flow path 73, and the downstream side of the combustion apparatus 31 is referred to as an auxiliary heating discharge flow path 75 to distinguish them.
The hot water supply flow path 30 has a hot water discharge side top connection portion 14 of the storage tank 10 as a base end, and hot water flows backward toward the storage tank 10 in the middle of the flow path from the storage tank 10 to the combustion device (auxiliary heat source) 31. In order to prevent this, a check valve 52 is provided. That is, a check valve 52 is provided in the auxiliary heating forward flow path 73. In the present embodiment, the check valve 52 is provided in the middle of the flow path from the storage tank 10 to the combustion device (auxiliary heat source) 31. That is, in the present embodiment, the check valve 52 is provided on the downstream side of the storage tank 10, but the check valve 52 may be provided on the upstream side of the storage tank 10 instead. That is, the position of the check valve 52 may be changed in a storage water supply channel 50a described later.
Further, an inlet side temperature sensor 33 and an auxiliary heating outgoing water amount sensor 63 are provided downstream of the check valve 52 in the hot water flow direction (combustion device 31 side).
That is, the auxiliary heating outgoing water flow rate sensor 63 is provided in the auxiliary heating outgoing flow path 73.
In the middle of the hot water supply passage 30, a main flow portion 53 and a branch flow portion 55 of a premixing bypass flow passage 50b described later are connected.
In other words, the main flow portion 53 and the tributary portion 55 of the premixing bypass flow channel 50 b are connected to the auxiliary heating forward flow channel 73.

  The inlet-side temperature sensor 33 is installed at a position downstream of the connecting portion between the hot water supply channel 30 and the premixing bypass channel 50 b and upstream of the combustion device (auxiliary heat source) 31. Therefore, the inlet-side temperature sensor 33 is the hot water after the hot water discharged from the storage tank 10 and the hot water supplied through the main flow portion 53 and the tributary portion 55 of the premixing bypass flow path 50b are mixed. Can detect temperature.

  Further, since the auxiliary heating outgoing water amount sensor 63 is also provided at the same position of the auxiliary heating outgoing flow path 73, the hot water supplied through the main flow portion 53 and the tributary portion 55 of the premixing bypass flow passage 50b is provided. The total amount of hot water after mixing can be detected. That is, the total amount of water supplied to the combustion device (auxiliary heat source) 31 is detected.

A portion of the hot water supply flow path 30 connected to the downstream side of the combustion device (auxiliary heat source) 31 (auxiliary heating discharge flow path 75) has a proportional valve 37, an outlet side temperature sensor 38, and a flowing water detection sensor 40. Is provided. In addition, in this embodiment, although the flowing water detection sensor 40 was provided, this is also omissible.
Further, downstream of the flowing water detection sensor 40 is divided into two flow paths via a three-way valve 67. One of them is a general hot water supply channel 68 used for general hot water supply such as currants, and the other is a bath dropping channel 66. The bath drop channel 66 is provided with a drop water amount sensor 74 for detecting the drop amount into the bathtub 72.

The combustion device (auxiliary heat source) 31 incorporates a burner 41 and a heat exchanger 43 for burning fuel such as gas and kerosene as in a conventionally known hot water heater, and heat energy generated by combustion of the fuel. The hot water is heated using The burner 41 of the combustion device (auxiliary heat source) 31 is supplied with fuel via a proportional valve (not shown), and the amount of combustion is increased or decreased according to the amount of water or water temperature supplied to the combustion device (auxiliary heat source) 31.
The combustion device (auxiliary heat source) 31 has higher hot water heating capability than the heat generating portion 5. The combustion device (auxiliary heat source) 31 performs a combustion operation only in a special case such as when the temperature of the hot water discharged from the storage tank 10 is low, and heats the hot water flowing in the hot water supply passage 30. Acts as an auxiliary heat source. The combustion device (auxiliary heat source) 31 uses one of the operating conditions that water flow is detected by the flowing water detection sensor 40.

  The water supply channel 50 is a channel for supplying hot water from an external water supply source. The water supply channel 50 includes a pressure reducing valve 49 and a water supply side water amount sensor 48 in the middle, and is branched into a storage water supply channel 50a and a premixing bypass channel 50b on the downstream side in the hot water flow direction. Yes.

  The storage water supply channel 50 a is connected to a water supply bottom opening 15 provided on the bottom side of the storage tank 10. Thereby, the cogeneration system 1 is configured to be able to introduce low-temperature hot water supplied from the outside from the bottom side of the storage tank 10.

  The premixing bypass flow path 50b is a flow path for joining the hot water supplied from the outside to the hot water flowing through the hot water supply flow path 30. In the middle of the premixing bypass flow path 50b, the incoming water temperature sensor 56 for detecting the temperature of the hot water joining the hot water supply flow path 30 and the hot water flow backward from the hot water supply flow path 30 toward the water supply source. A check valve 57 is provided for preventing the above-described problem.

  The premixing bypass flow path 50 b is configured to be branched into a main flow portion 53 and a branch flow portion 55 at a branch portion 54 on the downstream side of the check valve 57. The main flow part 53 has a flow rate adjustment valve 32 at a position downstream of the branch part 54, and the amount of hot water joining the hot water supply flow path 30 can be adjusted by adjusting the opening degree of the flow rate adjustment valve 32. it can.

  The tributary part 55 has an electromagnetic valve 58 at a position downstream of the branch part 54. The solenoid valve 58 is a valve that is opened when the power is not supplied. When the flow rate adjusting valve 32 cannot be opened due to a power failure, the hot water in the storage tank 10 is discharged as it is, and so-called hot hot water is discharged. It is provided to prevent it from happening.

  The pre-mixing bypass flow path 50 b is bypassed by a post-mixing bypass flow path 35 in the middle of the hot water supply flow path 30 and downstream of the combustion device (auxiliary heat source) 31. That is, the post-mixing bypass flow path 35 is connected to the auxiliary heating discharge flow path 75. One end of the post-mixing bypass flow path 35 is in the middle of the pre-mixing bypass flow path 50 b and is connected to a position upstream of the check valve 57.

  In the middle of the post-mixing bypass flow path 35, a flow rate adjustment valve 36a and a check valve 36b are provided. The check valve 36b blocks the flow of hot water from the hot water supply flow path 30 side to the premixing bypass flow path 50b side.

  The operation of the cogeneration system 1 is controlled by the control means 80. The control means 80 is the same as that provided in a conventionally known cogeneration system, and can be configured to include, for example, a CPU and a memory in which a predetermined control program is built. The control means 80 includes a valve and a heating unit 5 provided in each part of the cogeneration system 1 based on detection signals of sensors provided in each part, data stored in a memory, and the like, a combustion device (auxiliary heat source). It is set as the structure which controls operation | movement of 31 grade | etc., And optimizes the total energy efficiency of the cogeneration system 1. FIG.

  Next, a general operation of the cogeneration system 1 of the present embodiment will be briefly described with reference to the drawings. The cogeneration system 1 can operate by selecting an operation mode from an operation mode group including a storage mode, a hot water supply mode, a heating mode, and a detour mode.

(Storage mode)
FIG. 3 is an operation principle diagram illustrating an operation state when the cogeneration system and the hot water supply system illustrated in FIG. 1 operate in the storage mode.
The storage mode is generated along with the operation of the power generator 2 by operating the circulation pump 25 to generate a water flow in the tank circulation flow path 20a of the energy recovery system C as indicated by hatching or an arrow in FIG. This is an operation mode in which exhaust heat (heat energy) is recovered to heat the hot water and the hot water is stored in the storage tank 10. In the storage mode, the temperature of the hot water flowing through the heating return side flow path 22 toward the storage tank 10, that is, the temperature of the hot water detected by the temperature sensor 27 is equal to or higher than a predetermined temperature (hereinafter referred to as temperature α if necessary). It is an operation mode implemented on condition that it is.

(Hot water supply mode)
FIG. 4 is an operation principle diagram showing an operation state when the cogeneration system and the hot water supply system shown in FIG. 1 operate in the hot water supply mode.
The hot water supply mode is an operation mode in which hot water is supplied using hot hot water stored in the storage tank 10 in the above-described storage mode. When the cogeneration system 1 operates in the hot water supply mode, a hot water flow as indicated by hatching or an arrow in FIG. 4 occurs.

  More specifically, when the cogeneration system 1 operates in the hot water supply mode, the opening degree of the flow rate adjustment valve 32 provided in the main flow portion 53 of the premixing bypass flow path 50b is adjusted. At this time, the control means 80 energizes the electromagnetic valve 58 and closes the electromagnetic valve 58. Thus, a low-temperature hot water supplied from an external water supply source is adjusted to a state where it can join the hot water supply flow passage 30 by a predetermined amount via the main flow portion 53 of the premixing bypass flow passage 50b.

  In this state, when low-temperature hot water is introduced from the outside through the hot water supply / water supply system H, a part of the low-temperature hot water supplied from an external water supply source is stored as shown in FIG. It flows into the storage tank 10 from the bottom opening 15 for water supply through the passage 50a. Accordingly, hot hot water stored on the top side of the storage tank 10 is discharged through the hot water discharge side top connection portion 14 and flows into the hot water supply flow path 30. That is, when hot water is introduced into the bottom of the storage tank 10 via the hot water / water supply system H, hot hot water accumulated on the top side of the storage tank 10 is pushed up to the top side and pushed out to the hot water supply pipe 30.

  On the other hand, the remaining portion of the low-temperature hot water supplied from the external water supply source flows into the premixing bypass flow path 50 b and is introduced into the hot water supply flow path 30 through the main flow part 53. This hot water is discharged from the hot water discharge side top connection portion 14 of the storage tank 10, merged with hot water flowing through the hot water supply flow path 30, and mixed.

  The control means 80 confirms the temperature of the hot water flowing through the hot water supply passage 30 by the inlet side temperature sensor 33. Here, when the temperature of the hot water detected by the inlet side temperature sensor 33 is equal to the temperature of hot water to be discharged from the currant 34 or the like (hot water supply set temperature), the control means 80 is configured to use the combustion device (auxiliary heat source) 31. Will not start. Thereby, the hot water passes through the combustion device (auxiliary heat source) 31 and is discharged from the currant 34 as it is.

When the detected temperature of the inlet side temperature sensor 33 is higher than the hot water supply set temperature, a valve opening command is issued from the control means 80 to the flow rate adjusting valve 36a. That is, the detected temperature of the inlet side temperature sensor 33 is fed back to the flow rate adjustment valve 36a, and the opening degree of the flow rate adjustment valve 36a is adjusted. As a result, low-temperature hot water supplied from an external water supply source joins the post-mixing bypass flow path 35 to the hot water supply flow path 30 and is mixed with hot water flowing through the hot water supply flow path 30. Thereby, the hot water temperature in the currant 34 is adjusted to the hot water supply set temperature.
On the other hand, when the temperature of the hot water detected by the inlet side temperature sensor 33 is lower than the temperature to be discharged from the currant 34, the combustion device (auxiliary heat source) 31 is activated and the hot water is heated. At this time, the amount of heat required for heating is calculated from the temperature of the hot water detected by the inlet side temperature sensor 33 and the total amount of water supplied to the combustion device (auxiliary heat source) 31 detected by the auxiliary heating outgoing water amount sensor 63. The amount of fuel supplied to the burner 41 is controlled so as to match this amount of heat.

In the cogeneration system 1 of the present embodiment, two openings are provided at the bottom of the storage tank 10, one functioning as the circulation channel bottom opening 12 and the other functioning as the water supply bottom opening 15, Hot water supplied to the power generation device 2 side is taken out from the road bottom opening 12. That is, the flow path for supplying the cooling water to the power generation device 2 side is not directly connected to the water supply source, but is connected via the storage tank 10.
Therefore, the water introduced from the external water supply source at the time of hot water supply does not flow directly into the power generation device 2, but the external water supply once enters the storage tank 10 through the water supply bottom opening 15 and enters the tank circulation channel 20a. The water in the storage tank 10 is sucked out or pushed out and flows in. Therefore, the cold water supply from the outside flows directly into the fuel cell and the flow rate is greatly changed, and the temperature change of the water exchanged with the fuel cell is small.

(Heating mode)
FIG. 5 is an operation principle diagram illustrating an operation state when the cogeneration system and the hot water supply system illustrated in FIG. 1 operate in the heating mode.
The heating mode is an operation mode in which hot water or a heat medium in the heating-side circulation circuit 70 is subjected to heat exchange heating in the heat exchanger 71 and supplied to the heating terminal 65. When the heating mode is selected, a circulating flow of hot water or a heat medium is generated as indicated by hatching or arrows in FIG.

(Bypass mode)
FIG. 6 is an operation principle diagram illustrating an operation state when the cogeneration system and the hot water supply system illustrated in FIG. 1 operate in the bypass mode.
In the bypass mode, the circulation pump 25 is operated in a state in which the bypass circulation passage 20b that bypasses the storage tank 10 is configured in the energy recovery system C by adjusting the opening degree of the three-way valve 28, and stored in the bypass circulation passage 20b. In this operation mode, a circulating flow of hot water that bypasses the tank 10 is generated. When the bypass mode is selected, in the energy recovery system C, a hot water circulation flow as shown by an arrow in FIG.
As described above, the detour mode is an operation performed when the power generation device 2 is cold, such as in the initial operation.

  Next, the operation when the cogeneration system is trial run or when water is poured into the system at the installation site will be described. The operations described below are operations specific to the cogeneration system of the present invention, and will be described in detail.

The cogeneration system of the present embodiment includes a tank water injection mode and an in-pipe water injection mode as operation modes for trial operation. When water is injected into the system at the installation site, the tank water injection mode is executed first, and then the pipe water injection mode is executed. Therefore, the tank water injection mode will be described first.
(Tank water injection mode)
7, 8, and 9 are operation principle diagrams showing an operation state when the cogeneration system and the hot water supply system shown in FIG. 1 are operated in the tank pouring mode. FIG. 10 is a flowchart when the tank water injection mode is executed.

The tank water injection mode is an operation of pouring water into the storage tank 10 and completely filling the storage tank 10 with water.
In the tank water injection mode, water is introduced into the hot water supply flow path 30 from an external water supply source with the currant 34 being opened as an operation performed by the operator. Also, an operation board (not shown) is operated to select the tank water injection mode.
By selecting the tank water injection mode, the tank water injection mode is executed in accordance with the flowchart of FIG.

That is, when it is confirmed in step 1 that the tank pouring mode has been selected, the process proceeds to step 2 where only the main flow path valves during hot water supply are opened, and in step 3, all the tributary flow path valves are closed. It is done.
That is, the storage water supply flow path 50a, the water supply bottom opening 15 of the storage tank 10, the hot water discharge side top connection 14 of the storage tank 10, the hot water supply flow path 30, the combustion device (auxiliary heat source) 31, and the general hot water supply flow path 68 are straight. Only the flow path to be connected is opened, and the main flow section 53 and the tributary section 55 of the premixing bypass flow path 50b and the postmixing bypass flow path 35 are closed.
More specifically, the proportional valve 37 provided on the downstream side of the combustion device (auxiliary heat source) 31 is fully opened, the flow rate adjustment valve 32 provided in the main flow portion 53 of the premixing bypass flow path 50b is fully closed, The electromagnetic valve 58 of the branch section 55 is closed, and the flow rate adjustment valve 36a of the postmixing bypass flow path 35 is fully closed.
That is, all the channels other than the channel directly connected from the storage tank 10 among the channels connected to the auxiliary heating forward channel 73 are closed.
The valve on the energy recovery system C side may be opened or closed, but for ease of explanation, the open / close valve 24 of the bypass branch flow path 61 is closed and the three-way valve (flow path switching means) 28 of the heating branch flow path 60 is closed. Will close the storage tank 10 side (port c).
FIG. 7 shows the valves that are closed in the tank pouring mode in black, and the open valves in white.

  As a result, the flow path directly communicating with the auxiliary heating forward flow path 73 from the water supply port is blocked. Therefore, the entire amount of water entering from the water supply port passes through the water supply side water amount sensor 48 and flows into the storage tank 10, and the entire amount of water discharged from the storage tank 10 passes through the auxiliary heating forward water amount sensor 63 and flows from the currant 34. Discharged.

In the subsequent step 4, the detected water amount of the water supply side water amount sensor 48 and the detected water amount of the auxiliary heating outgoing water amount sensor 63 are compared, and the difference between them is calculated.
As described above, the storage water supply flow path 50a, the water supply bottom opening 15 of the storage tank 10, the hot water discharge side top connection 14 of the storage tank 10, the hot water supply flow path 30, the combustion device (auxiliary heat source) 31, and the general hot water supply flow Since only the straight flow path connecting the paths 68 is opened and the main flow section 53 and the tributary section 55 of the premixing bypass flow path 50b and the postmixing bypass flow path 35 are closed, the total amount of water entering from the water supply port is Passes through the water supply side water amount sensor 48 and flows into the storage tank 10. Further, the entire amount of water discharged from the storage tank 10 passes through the auxiliary heating outgoing water amount sensor 63.
Therefore, if the storage tank 10 is full, the amount of water entering the storage tank 10 and the amount of water discharged from the storage tank 10 should be equal. Therefore, if the difference between the detected water amount of the water supply side water amount sensor 48 and the detected water amount of the auxiliary heating outgoing water amount sensor 63 disappears, it is evidence that the storage tank 10 is full.
Therefore, in step 5 that follows, it is determined whether or not the difference between the detection values of the water quantity sensors 63 and 48 has become zero (less than a certain value). Actually, it is unavoidable that the detection values of the water amount sensors 63 and 48 have a certain amount of error. Therefore, it is determined whether or not the two values are actually the same in consideration of the sensor error.

  Further, when comparing the detection values of both water quantity sensors 63 and 48 in step 5, it is desirable to consider leakage of the flow rate adjusting valve 36a. That is, when comparing the detection values of the water quantity sensors 63 and 48, the flow rate adjustment valve 36a provided in the post-mixing bypass flow path 35 is closed, but the flow rate adjustment valve 36a is water-impervious due to its structure. Capability is inferior compared to solenoid valves. Therefore, a minute water leak may occur from the flow rate adjustment valve 36 a, and water may leak to the downstream side of the auxiliary heating outgoing water amount sensor 63 through the post-mixing bypass flow path 35. Therefore, in step 5, it is desirable to determine whether or not the detection values of the water amount sensors 63 and 48 are the same in consideration of leakage of the flow rate adjusting valve 36a.

If it is determined in step 5 that the detection values of both water quantity sensors 63 and 48 are the same, a display informing that water injection has been completed is issued in step 6 and the series of operations is completed. The display notifying that water injection has been completed may be a visual display that displays a figure or a character on the display screen, or may be an auditory display such as a buzzer or sound.
If you have a water injection solenoid valve for trial operation, close the solenoid valve to stop water injection.

The flowchart shown in FIG. 10 describes only the main operation of the water injection mode, but other requirements may be added to confirm the completion of water injection to the water supply tank 10. For example, it may be a condition that the detected water amounts of both the water amount sensors 63 and 48 are not zero, or that the flowing water detection sensor 40 detects a water flow.
In addition, a condition that water has passed for a certain period of time, a condition that the detection value of the water flow sensor is stable, and a condition that the detection values of the two water flow sensors are the same continue for a certain period of time. Also good.

In the above description, the valve on the energy recovery system C side is closed. However, as described above, the valve on the energy recovery system C side may be opened or closed. 8 and 9 show the flow of water when the valve on the energy recovery system C side is opened. That is, in FIG. 8, the storage tank 10 side of the three-way valve 28 is opened. In FIG. 9, the on-off valve 24 of the bypass branch flow path 61 is also opened.
Also in FIGS. 8 and 9, the valve that is closed in the tank pouring mode is shown in black, and the open valve is shown in white. As shown in FIGS. 8 and 9, even when the valve on the energy recovery system C side is opened, the entire amount of water flowing into the energy recovery system C returns to the storage tank 10. Therefore, as in the previous case, the entire amount of water that has entered from the water supply port passes through the water supply side water amount sensor 48 and flows into the storage tank 10. Further, the entire amount of water discharged from the storage tank 10 passes through the auxiliary heating outgoing water amount sensor 63.
Therefore, if the storage tank 10 is full, the amount of water entering the storage tank 10 and the amount of water discharged from the storage tank 10 should be equal, and the difference between the detection values of the two water amount sensors 63 and 48 is the same. If it is determined whether or not it is zero, it can be determined whether or not the storage tank 10 is full.

In the present embodiment, as a sensor that can detect the amount of water discharged from the storage tank 10, there is a dropped water amount sensor 74 in addition to the above-described auxiliary heating outgoing water amount sensor 63, but the dropped water amount sensor 74 is used as the auxiliary heating outgoing water amount. It cannot be used in place of the sensor 63.
That is, in the present embodiment, the hot water supply channel 30 has a general hot water supply channel 68 and a bath dropping channel 66 that are used for general hot water such as currants. If the dropped water amount sensor 74 is used in place of the auxiliary heating outgoing water amount sensor 63, the current hot water flow path 68 must not be opened during the water injection operation. Here, the bath dropping channel 66 is opened and closed by an electrical signal, while the general hot water supply channel 68 is manually opened and closed. In addition, since the trial operation of the equipment is often performed while a plurality of workers communicate with each other, other workers often open the currant 34 or the like during the water injection mode. Therefore, there is a concern that confirmation of completion of water injection will be delayed or inaccurate.

  On the other hand, when the auxiliary heating outgoing water amount sensor 63 is used as in the present embodiment, the attachment position is upstream of the branching portion with the bath dropping channel 66, and the dropping starts or other plugs are opened and closed. Regardless of this, the amount of water discharged from the storage tank 10 can be accurately detected.

In the above description, only the main flow path valve is opened in step 2, and all the tributary flow path valves are closed in step 3, and water is always poured into the storage tank 10 in this state. However, for example, each valve is opened and closed sequentially, water is poured into the storage tank 10 in this state, and the valve can be brought into the above-described state only when it is determined whether or not the inside of the storage tank 10 is full. It is.
(Piping water injection mode)
FIG. 11 is an operation principle diagram showing an operation state when the cogeneration system and the hot water supply system shown in FIG. 1 operate in the in-pipe water injection mode. FIG. 12 is a flowchart when the in-pipe water injection mode is executed.
The in-pipe water injection mode is an operation mode for injecting water into the energy recovery system C.
In the in-pipe water injection mode, water is introduced into the energy recovery system C from an external water supply source with the currant 34 opened as an operation performed by the operator. Further, an operation board (not shown) is operated to select the in-pipe water injection mode.
By selecting the tank water injection mode, the pipe water injection mode is executed in accordance with the flowchart of FIG.

That is, when it is confirmed in step 1 that the in-pipe water injection mode has been selected, the process proceeds to step 2 where the three-way valve 28 is in a half-open state. That is, as described above, the three-way valve (flow path switching means) 28 is a three-way switching valve in which the valve body 62 rotates within a housing 59 having three openings (ports) a, b, and c. As shown in FIG. 2 (a), two ports a, b out of the three ports a, b, c constituting the three-way valve 28 are connected to close the port c, or three ports as shown in FIG. 2 (b). Of the ports a, b, and c, two ports a and c are communicated with each other and the port b is closed.
On the other hand, when the in-pipe water injection mode is selected, the stepping motor is stopped at an intermediate position, and the valve body 62 is moved to a position where the three ports a, b, and c communicate as shown in FIG. Put.
In step 3, the on-off valve 24 of the bypass branch passage 61 is opened.
FIG. 11 shows a valve that is closed in the in-pipe water injection mode in black, and an open valve in white.

Furthermore, in step 4, the circulation pump 25 in the power generator 2 is started. As will be described later, the energy recovery system C can be filled with water without starting the circulation pump 25.
As a result, the water that has entered from the water supply port once enters the storage tank 10 through the water supply bottom opening 15, and is drawn by the circulation pump 25 to flow from the circulation channel bottom opening 12 to the heating-out side flow path of the energy recovery system C. Enter 21. Subsequently, the hot water supply system apparatus 3 is exited and enters the power generation apparatus 2, and then returns to the hot water supply system apparatus 3.

Further, the water that has returned to the hot water supply system device 3 enters the heating return side flow path 22 and flows into a heating branch flow path 60 and a bypass branch flow path 61 that is a bypass flow path. The water that has flowed into the bypass branch channel 61 returns to the storage tank 10 as it is.
Therefore, in the energy recovery system C, a water flow is generated in the flow path that returns to the storage tank 10 via the heating-out flow path 21, the power generation device 2, and the bypass branch flow path 61, and the internal air is pushed out to form water and water. Replaced.

  The water flowing through the heating branch flow path 60 reaches the three-way valve 28. Since the three-way valve 28 communicates with the three ports a, b, and c, the water flowing through the heating branch flow path 60 is stored in the storage tank. Return to 10. Accordingly, a water flow is also generated in the flow path passing through the heating branch flow path 60, and the air inside the heating branch flow path 60 is pushed out and replaced with water.

Further, since the three-way valve 28 is in a half-open state, a bypass circulation passage 20b that bypasses the storage tank 10 is also communicated with the energy recovery system C, and a passage that passes through the tank bypass passage 23 is also provided by the drive pump 25. Water flow is generated.
That is, the negative pressure of the drive pump 25 causes a water flow in the tank bypass flow path 23 toward the heating forward flow path 21, and the water leaves the hot water supply system device 3 and enters the power generation device 2, and then the hot water supply system. It returns to the apparatus 3 and returns to the storage tank 10 via the heating branch channel 60 or the bypass branch channel 61. Therefore, the air inside the tank bypass channel 23 is pushed out and replaced with water.
Accordingly, water flows are generated in all the flow paths of the energy recovery system C, and the energy recovery system C is entirely replaced with water.

In the above description, the circulation pump 25 in the power generation device 2 is started in step 4, but the energy recovery system C can be filled with water without starting the circulation pump 25.
When the circulation pump 25 is not started, the storage tank 10 is first filled with water, and the inside of the storage tank 10 becomes a positive pressure and water is pushed out from the storage tank 10.
FIG. 13 is an operation principle diagram illustrating an operation state when the cogeneration system and the hot water supply system illustrated in FIG. 1 operate in the in-pipe water injection mode, and illustrates a case where the operation is performed without starting the circulation pump.
That is, the water that has entered from the water supply port once enters the storage tank 10 through the water supply bottom opening 15 and temporarily fills the storage tank 10 with water. Further, the supplied water enters the heating-out side channel 21 of the energy recovery system C from the circulation channel bottom opening 12 of the storage tank 10. Subsequently, the hot water supply system apparatus 3 is exited and enters the power generation apparatus 2, and then returns to the hot water supply system apparatus 3.
Further, the water that has returned to the hot water supply system device 3 enters the heating return side flow path 22 and flows into a heating branch flow path 60 and a bypass branch flow path 61 that is a bypass flow path. The water that has flowed into the bypass branch channel 61 returns to the storage tank 10 as it is.
Therefore, in the energy recovery system C, a water flow is generated in the flow path that returns to the storage tank 10 via the heating-out flow path 21, the power generation device 2, and the bypass branch flow path 61, and the internal air is pushed out to form water and water. Replaced.

  Further, since the three ports a, b, and c communicate with each other in the three-way valve 28, the water flowing through the heating branch flow path 60 returns to the storage tank 10. Accordingly, a water flow is also generated in the flow path passing through the heating branch flow path 60, and the air inside the heating branch flow path 60 is pushed out and replaced with water.

In addition, since the valve body 62 of the three-way valve 28 is in the middle position and the ports a, b, c are in a half-open state, the flow from the tank bypass passage 23 to the storage tank 10 through the heating return downstream passage 22a. The road is also open. Therefore, the water pushed out from the bottom opening 12 for the circulation flow path below the storage tank 10 enters the tank bypass flow path 23 and passes through the heating return downstream flow path 22a to the storage tank 10.
Therefore, the air inside the tank bypass channel 23 is pushed out and replaced with water.
Therefore, even when the circulation pump 25 is not activated, water flows in all the flow paths of the energy recovery system C, and the energy recovery system C is entirely replaced with water.
In addition, no abnormal noise was felt during execution of the in-pipe water injection mode.

  In the present embodiment, the tank bypass channel 23 can be filled with water even when the power generator 2 is not connected and the manual valves 16 and 17 are closed.

  In the present embodiment, when the operation is performed in the in-pipe water injection mode, the three-way valve 28 is always set to the midway position, but it is also conceivable that the three-way valve 28 is set to the midway position only for a certain period of time.

  In the above-described embodiment, the three-way valve 28 is provided at the connection portion between the tank bypass flow path 23 and the heating return side flow path 22, but the three-way valve 28 is positioned at the tank bypass flow path 23 and the heating forward flow path 21. You may provide in the connection part.

  In the above-described embodiment, the tank water injection mode and the in-pipe water injection mode are individually executed, but may be executed simultaneously in parallel.

  In the above-described embodiment, the fuel cell is used as the heat / electricity generator, but other devices such as a gas engine may be used. However, since the present invention is suitable for equipment with a small amount of water flowing through the system, it is most appropriate to apply it to cogeneration using a fuel cell.

It is an operation principle figure showing a cogeneration system and a hot water supply system which are one embodiment of the present invention. It is sectional drawing which shows the structure of a three-way valve, and figure (a) (b) (c) has shown the case where the attitude | position of a valve body differs, respectively. FIG. 2 is an operation principle diagram illustrating an operation state when the cogeneration system and the hot water supply system illustrated in FIG. 1 operate in a storage mode. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. 1 operate | move in hot water supply mode. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. 1 operate | move in heating mode. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. It is a flowchart at the time of performing tank pouring mode. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. It is a flowchart at the time of performing in-pipe water injection mode. It is an operation principle figure which shows the operation state at the time of the cogeneration system and hot water supply system which are shown in FIG. 1 operate | move in the in-pipe water injection mode, and shows the case where it performs without starting a circulation pump. In the cogeneration system of a prior art, it is an operation | movement principle figure of the principal part which shows a mode at the time of pouring water in the system. In the cogeneration system of a prior art, it is an operation | movement principle figure of the principal part which shows a mode at the time of pouring water in the system. It is explanatory drawing which shows the structure of a three-way valve. In the cogeneration system of this invention, it is an operation | movement principle figure of the principal part which shows a mode at the time of pouring water in a system | strain. In the cogeneration system of this invention, it is an operation | movement principle figure of the principal part which shows a mode at the time of pouring water in a system | strain.

Explanation of symbols

1 Cogeneration system 2 Power generator (heat and electricity generator)
3 Hot-water supply system 10 Storage tank 23 Tank bypass flow path 28 Three-way valve (flow path switching means)
32 Flow control valve 35 Post-mixing bypass flow path 36a Flow control valve 36b Check valve 43 Heat exchanger 48 Water supply side water amount sensor 50 Water supply flow path 50b Premixing bypass flow path 58 Solenoid valve 63 Auxiliary heating forward water amount sensor 73 Auxiliary Heating forward flow path 75 Auxiliary heating discharge flow path

Claims (6)

  A hot water supply system connected to a heat / electricity generator, comprising a storage tank for storing hot water heated by the heat / electricity generator, an auxiliary heating device, a water supply channel for supplying water to the storage tank, and a storage tank Provided with an auxiliary heating forward flow path for supplying discharged hot water to the auxiliary heating device, and an auxiliary heating discharge flow path discharged from the auxiliary heating device, and draining and consuming hot water from the storage tank as needed, In a hot water supply system in which hot water in a storage tank is heated by an auxiliary heating device and then discharged and consumed as required, the water supply flow path is provided with a water supply side water amount sensor, and the auxiliary heating forward flow path is provided with an auxiliary heating forward water amount sensor And a tank water injection mode for injecting water into the storage tank as an operation mode. In the tank water injection mode, water is supplied from the water supply passage to the storage tank, and the water detected by the water supply side water amount sensor And at least one of termination of the tank water injection mode, predetermined display, and stop of water supply to the storage tank, on the condition that the difference in the detected water amount of the auxiliary heating outgoing water amount sensor is less than a certain amount. A hot water supply system characterized by that.   It has a flow path from the water supply flow path to the auxiliary heating forward flow path without passing through the storage tank and a flow path from the water supply flow path to the auxiliary heating discharge flow path without passing through the storage tank. One of the conditions is that the valve is provided and the valve is closed, and the difference between the detected water amount of the water supply side water amount sensor and the detected water amount of the auxiliary heating forward water amount sensor is less than a certain value. 2. The hot water supply system according to claim 1, wherein at least one of an end of the operation, a predetermined display, and a stop of water supply to the storage tank is executed.   There is a post-mixing bypass flow channel that connects the water supply flow channel and the auxiliary heating discharge channel, and hot water that is discharged by mixing water flowing through the post-mixing bypass channel with hot water flowing through the auxiliary heating discharge channel. The temperature can be adjusted, and a valve is provided in the post-mixing bypass flow path. In the tank pouring mode, the bypass water amount adjustment valve is closed to detect the amount of water detected by the water supply side water amount sensor and the auxiliary heating forward water amount sensor. The hot water supply system according to claim 1 or 2, wherein the detected water amount is compared.   There is a premixing bypass flow channel that is connected between the storage tank and the water supply side water amount sensor, starting from the water supply flow channel, and a valve is provided in the premixing bypass flow channel. The hot water supply system according to any one of claims 1 to 3, wherein the detected water amount of the water supply side water amount sensor is compared with the detected water amount of the auxiliary heating forward water amount sensor with the on-off valve closed.   A tank circulation passage that circulates between the heat / electricity generator and the storage tank, a tank bypass passage that is connected to the tank circulation passage and bypasses the storage tank, and a passage that circulates through the tank bypass passage. A flow path switching means for switching between the flow paths circulating through the tank, and in the tank irrigation mode, the flow path switching means is temporarily or constantly connected between the heat / electricity generator, the storage tank, and the tank-by-bus flow path. The hot water supply system according to any one of claims 1 to 4, wherein the three parties are in communication.   A cogeneration system in which a heat / electricity generator having a fuel cell as a main part is connected to the hot water supply system according to any one of claims 1 to 5.

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