JP2014149147A - Heat supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent operation efficiency of a heat source from decreasing while storing heat with high density in a heat storage part, without causing fluctuation of the pressure and flow rate of a heat medium circulating through a heat reception part as the heat source.SOLUTION: A first heat medium circulation passage C is provided so that a first heat medium can flow into a heat storage part 10. A hot water flow passage L1 comprises: a water supply port to which pressurized water is supplied; heat exchangers 12, 13 installed in the heat storage part; and a hot water discharge port discharging high-temperature water. Water having flowed in from the water supply port is subjected to heat exchange to at least any of latent heat storage materials 20a, 20b and the first heat medium by the heat exchangers 12, 13, to be thereby flown out to the hot water discharge port. Consequently, heat supply is performed on a heat use side.

Description

  The present invention includes a first heat medium circulation path through which a first heat medium on the heat transfer side in the heat storage unit circulates between the heat receiving unit and the heat storage unit, and the heat storage unit is filled with a latent heat storage material. The heat of the first heat medium heated at the heat receiving part is configured to be stored in the latent heat storage material inside the heat storage part, and heat is generated from the heat storage part in a heat storage state using a hot water passage. The present invention relates to a heat supply system capable of supplying heat to the user side.

Conventionally, as a heat supply system, a flow path arranged to circulate hot water recovered from a heat receiving part to a heat storage part and water supplied as clean water are passed through the heat storage part to recover heat of the heat storage part. There is known one having a configuration in which a flow path arranged to be discharged as hot water supply is shared (see Patent Document 1).
On the other hand, each of the heat medium flow path for circulating the heat medium between the heat receiving section and the heat storage section provided in the heat source and the flow path on the hot water supply side through which water supplied as clean water flows are stored. What has the structure arrange | positioned inside a part is known (refer patent document 2).

JP 2012-180993 A Japanese Patent No. 3912232

In the configuration disclosed in Patent Document 1 above, fluctuations in the water supply pressure due to the opening and closing of the hot water supply side valve and fluctuations in the upper water pressure are directly transmitted to the heat receiving part of the heat source, so the flow rate of water circulating through the heat receiving part is not stable, Some heat sources (for example, fuel cells) do not normally operate as expected. For example, in the case of a fuel cell, the heat receiving portion is a condenser, and it is necessary to continue to condense a certain amount of water vapor 8 contained in the exhaust gas of the fuel cell during the operation. It may occur and lead to a decrease in power generation efficiency.
On the other hand, in order to solve the problem, as in the configuration disclosed in Patent Document 2 described above, a configuration in which each of the heat medium channel and the channel on the hot water supply side is disposed inside the heat storage unit is adopted. Then, the heat exchanger of the heat storage unit becomes complicated, and heat is lost by the amount of sensible heat of the increased heat exchanger volume, which is problematic in terms of thermal efficiency.
The present application has been made in view of the above problems, and its purpose is to store heat at a high density in the heat storage unit, but not to cause fluctuations in the pressure and flow rate of the heat medium circulating in the heat receiving unit. For example, the present invention is to provide a heat supply system capable of preventing a decrease in the operation efficiency of a fuel cell).

A heat supply system for achieving the above object is as follows:
A first heat medium circulation path through which the first heat medium on the heat supply side in the heat storage unit circulates is provided between the heat receiving unit and the heat storage unit,
The heat storage part is filled with a latent heat storage material,
The heat of the first heat medium heated at the heat receiving part is configured to be able to store heat to the latent heat storage material inside the heat storage part,
A heat supply system capable of supplying heat from the heat storage section in a heat storage state to a heat utilization side using a hot water flow passage,
The first heat medium circulation path is provided so that the first heat medium can flow into the heat storage unit,
The hot water flow passage is composed of a water supply port to which pressurized water is supplied, a first heat exchanger built in the heat storage unit, and a hot water outlet for hot water.
The water flowing in from the water supply port can supply heat to the heat utilization side by exchanging heat with at least one of the latent heat storage material and the first heat medium by the first heat exchanger and flowing out to the hot water outlet. There is a point.

According to the above characteristic configuration, the first heat medium circulation path and the hot water flow path are provided independently, and hot water flowing through the hot water flow path is not guided to the first heat medium circulation path. Even when the hot water supply pressure and flow rate change, the change in the water supply pressure and flow rate can be prevented from being transmitted to the heat receiving part in the heat source via the first heat medium circulation path. Thus, for example, when a fuel cell is used as a heat source and a condenser that condenses water vapor contained in exhaust gas is used as a heat receiving part, a certain amount of condensed water is secured in the condenser, and the condensed water As a result, the water self-supporting of the fuel cell can be realized and the operation of the fuel cell can be favorably sustained.
In addition, since the first heat medium circulating in the first heat medium circulation path is configured to flow into the heat storage section, the first heat medium circulation path is arranged inside the heat storage section as a heat exchanger. It is not necessary to install the heat storage unit, and the heat storage unit can be configured in a simple and compact manner, and the loss of sensible heat can be reduced by the amount of the compact configuration.

Further features of the heat supply system of the present application are as follows:
The heat storage unit is provided with a high temperature side heat storage unit into which the first heat medium heated at the heat receiving unit flows and a low temperature side heat storage unit through which the first heat medium returning to the heat receiving unit flows out.

  According to the above characteristic configuration, since the high temperature side heat storage unit into which the first heat medium raised in temperature at the heat receiving unit flows and the low temperature side heat storage unit from which the first heat medium returning to the heat receiving unit flows out are provided separately. For example, by setting the melting point of the latent heat storage material provided in the high temperature side heat storage unit to be close to the temperature of the first heat medium raised in temperature in the heat receiving unit, the high temperature side heat storage unit can store heat at a relatively high temperature. On the other hand, by setting the melting point of the latent heat storage material provided in the low temperature side heat storage unit to be lower than the upper limit temperature of the first heat medium required in the heat reception unit, the low temperature side heat storage unit passes through the low temperature side heat storage unit to the heat reception unit. The temperature of the 1st heat medium guide | induced can be reduced to less than the upper limit temperature of the 1st heat medium requested | required in a heat receiving part.

Further features of the heat supply system of the present application are as follows:
The hot water flow passage is arranged such that the hot water flowing through the hot water flow passage recovers the heat stored in the low temperature side heat storage unit and then recovers the heat stored in the high temperature side heat storage unit. .

  According to the above characteristic configuration, the hot water flowing through the hot water flow passage is collected in the high temperature side heat storage unit that stores heat at a relatively high temperature after the heat is collected in the low temperature side heat storage unit that stores heat at a relatively low temperature. Since the heat is recovered, the hot water can be sufficiently heated and supplied from the outlet.

Further features of the heat supply system of the present application are as follows:
In addition to the high temperature side heat storage unit and the low temperature side heat storage unit, the heat storage unit includes one or a plurality of medium temperature side heat storage units,
The first heat medium so that the first heat medium heated at the heat receiving part flows through the high temperature side heat storage part, the intermediate temperature side heat storage part, and the low temperature side heat storage part in the order described and returns to the heat receiving part. The medium circulation path is provided.

As in the above characteristic configuration, as the heat storage unit, a high temperature side heat storage unit, an intermediate temperature side heat storage unit, and a low temperature side heat storage unit are provided. By adopting a configuration that allows the side heat storage section to flow in the order described, even if the temperature of the first heat medium raised in the heat receiving section touches the low temperature side, the first heat medium is retained. Heat can be stored effectively.
When a description is added, for example, a solid polymer fuel cell (hereinafter abbreviated as PEFC) having a relatively low operating temperature is provided as a heat source, and the heat receiving unit is configured to recover the exhaust heat of the PEFC. The exhaust heat temperature of PEFC may drop from 60 ° C. during rated operation to about 48 ° C. At this time, if the melting point of the latent heat storage material of the high temperature side heat storage unit is set to about 53 ° C. (temperature set for the purpose of recovering exhaust heat during rated operation), the high temperature side heat storage unit uses latent heat to store heat. Therefore, the first heat medium flows to the downstream side without substantially radiating heat in the high temperature side heat storage section.
Therefore, as shown in the above characteristic configuration, by providing an intermediate temperature side heat storage unit filled with a latent heat storage material having a melting point of about 44 ° C. on the downstream side of the high temperature side heat storage unit, the high temperature side heat storage unit passes almost without radiating heat. The heat of the first heat medium at about 48 ° C. can be stored using latent heat in the intermediate temperature side heat storage section.
Further, on the downstream side of the intermediate temperature side heat storage unit, the temperature of the first heat medium returning to the heat receiving unit is set to less than 40 ° C. by filling the latent heat storage material having a melting point of about 36 ° C. in the low temperature side heat storage unit. be able to. As a result, when adopting a configuration in which PEFC is adopted as the heat source and the exhaust gas from the PEFC and the first heat medium are exchanged in the heat receiving part, water vapor contained in the exhaust gas is preferably condensed in the heat receiving part. It is possible to operate the PEFC in water self-sustained operation with the condensed water.

  In addition, in the above-described configuration, it may be possible to adopt a configuration in which only the intermediate temperature side heat storage unit and the low temperature side heat storage unit are provided without providing the high temperature side heat storage unit. Since the upper limit of the temperature is near the melting point (for example, 44 ° C.) of the intermediate temperature side heat storage part, when the temperature of the first heat medium raised in the heat receiving part is about 60 ° C., the heat at that temperature is effective. It will not be possible to store heat. In particular, when the heat stored in the heat storage unit is used for high-temperature heating, the auxiliary heat source device is operated when the recovery temperature is low, so that energy saving performance is reduced. So, in the said characteristic structure, the structure provided with a high temperature side heat storage part, a middle temperature side heat storage part, and a low temperature side heat storage part is employ | adopted for the heat storage part.

Further features of the heat supply system of the present application are as follows:
A heating circuit that circulates a second heat medium that is on the heat receiving side in the heat storage unit between the heat storage unit and the thermal load terminal is provided separately from the hot water flow passage.

  According to the above characteristic configuration, the heating circuit is provided separately from the hot water flow passage, so that the heat stored in the heat storage unit is not only hot water supply having a relatively low temperature demand but also relatively high temperature demand. The heat load terminal can also be used, and heat in a wide temperature range stored in the heat storage section can be used more effectively.

Further features of the heat supply system of the present application are as follows:
In the heating circuit, the second heat medium is higher than the return temperature of the second heat medium after exiting the thermal load terminal among the high temperature side heat storage unit, the intermediate temperature side heat storage unit, and the low temperature side heat storage unit. It exists in the point arrange | positioned in the state which collect | recovers the heat | fever of the thermal storage part with which the said latent heat storage material of high melting | fusing point is filled.

According to the above characteristic configuration, for example, the latent heat storage material of the low temperature side heat storage unit can be prevented from melting by the heat of the second heat medium returning at a temperature higher than the melting point of the latent heat storage material of the low temperature side heat storage unit. .
Thereby, the heat of the 1st heat medium which passes a low temperature side heat storage part can be appropriately recovered with latent heat with the latent heat storage material of a low temperature side heat storage part, and the 1st heat medium can be temperature-fallen to the temperature below 40 degreeC. As a result, when the heat receiving part is used as a condenser for condensing the water vapor contained in the exhaust gas of PEFC, the water vapor contained in the exhaust gas is appropriately condensed in the heat receiving part, and the PEFC can be operated in a water self-supporting manner.

Further features of the heat supply system of the present application are as follows:
The heating circuit is arranged in a state where the second heat medium recovers only the heat stored in the high temperature side heat storage unit, or in a state where only the heat stored in the high temperature side heat storage unit and the intermediate temperature side heat storage unit is recovered. Established,
The hot water flow passage is in such a manner that the hot water is collected in the order described in the order of the heat stored in the low temperature side heat storage unit, the intermediate temperature side heat storage unit, and the high temperature side heat storage unit.

According to the above characteristic configuration, the second heat medium that flows through the heating circuit can recover at least the relatively high-temperature heat stored in the high-temperature side heat storage unit, so the relatively high-temperature heat is compared. It can be used effectively at a thermal load terminal that has a high heat demand, and the frequency with which the auxiliary heat source machine is operated can be reduced, thus improving energy saving.
Moreover, since the said heating circuit is arrange | positioned in the state which does not collect | recover the heat which the 2nd heat carrier stored in the low temperature side heat storage part, it may return at high temperature rather than melting | fusing point of the latent heat storage material of a low temperature side heat storage part. It is possible to avoid melting of the latent heat storage material in the low-temperature side heat storage unit due to the heat of the second heat medium.
Furthermore, since the hot water flow passage is disposed so that the hot water is stored in the low temperature side heat storage unit, the intermediate temperature side heat storage unit, and the high temperature side heat storage unit in the order described, The latent heat storage material is dissipated to the water supply having a temperature lower than its melting point (for example, 36 ° C.), and the heat storage amount in the low temperature side heat storage unit can be given a surplus, and the heat of the first heat medium returning to the heat receiving unit Can be appropriately recovered by the latent heat of the latent heat storage material of the low temperature side heat storage section, and the first heat medium can be lowered to a temperature of less than 40 ° C. and returned to the heat receiving section.
Thereby, when making a heat receiving part work as a condenser which condenses the water vapor | steam contained in the waste gas of PEFC, the water vapor | steam contained in waste gas is appropriately condensed in a heat receiving part, and PEFC can be water-self-supported.

Further features of the heat supply system of the present application are as follows:
The heat receiving part collects exhaust heat of exhaust gas generated in a heat source machine,
The melting point of the intermediate temperature side latent heat storage material filled in the intermediate temperature side heat storage unit is set to be lower than the lower limit temperature of the exhaust gas discharged from the heat source unit.

For example, when the heat source is configured as a PEFC, the temperature of the exhaust gas decreases from the rated 60 ° C. to about 48 ° C. (hereinafter referred to as the lower limit temperature of the exhaust gas) due to fluctuations in the operating state of the PEFC. There is.
According to the above characteristic configuration, the temperature of the exhaust gas is set to the lower limit by setting the melting point of the intermediate temperature side latent heat storage material filled in the intermediate temperature side heat storage unit to be lower than the lower limit temperature (48 ° C.) of the exhaust gas discharged from the heat source unit. Even when the temperature is lowered to the temperature, the heat of the first heat medium that has recovered the exhaust heat of the exhaust gas can be stored at least in the intermediate temperature side heat storage section.
Thereby, the heat of the first heat medium is not stored in the high temperature side heat storage unit and the intermediate temperature side heat storage unit, but is stored only in the low temperature side heat storage unit, and the amount of heat stored in the low temperature side heat storage unit reaches the upper limit, and the first heat It is possible to prevent the medium from being guided to the heat receiving part without sufficiently lowering the temperature (at a temperature of 40 ° C. or higher).

Further features of the heat supply system of the present application are as follows:
The heat receiving unit is a condenser that causes heat exchange between the exhaust gas generated in the fuel cell and the heat medium in the heat medium circulation path, and condenses water vapor contained in the exhaust gas,
The melting point of the low-temperature side latent heat storage material filled in the low-temperature side heat storage unit is set to be lower than a condensation temperature for condensing water vapor contained in the exhaust gas.

  According to the above characteristic configuration, the heat receiving unit is configured by the condenser for exchanging heat between the exhaust gas generated in the fuel cell and the first heat medium in the first heat medium circuit, and is provided in the low temperature side heat storage unit. Since the melting point of the low-temperature side latent heat storage material is set to a temperature lower than the condensation temperature at which the water vapor contained in the exhaust gas is condensed by the condenser, a part of the low-temperature side latent heat storage material is cooled by hot water on the heat utilization side. In a state where cold heat is stored (for example, when the low temperature side latent heat storage material is in a solid phase), the temperature of the first heat medium that flows out of the low temperature side heat storage section and is guided to the condenser is converted into exhaust gas by the condenser. The contained water vapor can be condensed appropriately. Thereby, the water self-sustained operation of the fuel cell can be realized using the condensed water.

Schematic configuration diagram of a heat supply system according to the first embodiment The figure which shows the internal structure of the thermal storage tank which concerns on 1st Embodiment. Schematic configuration diagram of a heat supply system according to the second embodiment The figure which shows the internal structure of the heat storage tank which concerns on another embodiment.

While the heat supply system 100 of the present invention stores heat at high density in a high temperature side heat storage tank 10a (an example of a high temperature side heat storage part) and a low temperature side heat storage tank 10b (an example of a low temperature side heat storage part) that are heat storage parts, As a result, it is possible to prevent the operating efficiency of the fuel cell 30 having the heat receiving portion 37 from being lowered without causing fluctuations in the pressure and flow rate of the first heat medium flowing through the heat receiving portion 37.
Since the heat supply system 100 of the present invention can sufficiently reduce the temperature of the first heat medium guided to the heat receiving portion 37, for example, a solid oxide fuel cell, a solid polymer fuel cell, etc. When this is applied to the fuel cell 30, water self-sustained operation can be executed in the fuel cell 30. Therefore, in the following, after describing the configuration of the fuel cell 30, a first embodiment in which the heat supply system 100 of the present invention is applied to the fuel cell 30 will be described with reference to FIGS.

[First Embodiment]
As shown in FIG. 1, the fuel cell 30 includes a desulfurizer 33 that removes sulfur compounds from the fuel gas F, and reacts the desulfurized fuel gas F with steam in the presence of a steam reforming catalyst to produce reformed gas. A reformer 34 to be generated, and a transformer 35 for performing a transformation process for reacting carbon monoxide in the reformed gas with water vapor in the presence of a catalyst to transform it into carbon dioxide are arranged in the order of description, and the transformation process is performed. Thus, a hydrogen-rich reformed fuel gas from which carbon monoxide has been removed is generated.
The generated reformed fuel gas is supplied to the anode electrode (fuel electrode) 32, and oxygen in the air is supplied to the cathode electrode (air electrode) 31, and the anode electrode (fuel electrode) 32 and the cathode electrode are supplied. It is configured to be able to generate electric power by an electrochemical reaction with the (air electrode) 31.

On the other hand, the exhaust gas E discharged in the process of generating electric power flows through the exhaust gas flow passage 38 and is sent to the condenser 37 (an example of a heat receiving unit). The condenser 37 is provided with a first heat medium circulation path C that circulates a first heat medium, which will be described later, and the temperature at which the first heat medium enters the condenser 37 is a low temperature TL (for example, 37 ° C.). Thereby, the exhaust gas E is cooled to 40 ° C. or less by heat exchange with the first heat medium, and the water vapor contained therein is condensed. The condensed water is once stored in the recovered water tank 36, purified by a known water treatment device (not shown), and guided to the reformer 34.
By adopting this configuration, the fuel cell 30 can perform a so-called water self-sustained operation in which water necessary for steam reforming is generated inside itself.

The heat supply system 100 of the present invention includes the first heat medium circulation path C that circulates the first heat medium between the condenser 37 (an example of the heat receiving unit) of the fuel cell 30 and the heat storage unit 10 described above. A first circulation pump P1 that pumps the first heat medium in the first heat medium circulation path C is provided.
As the heat storage unit 10, a high temperature side heat storage tank 10 a (an example of a high temperature side heat storage unit) into which the first heat medium heated by the condenser 37 flows, and a low temperature side from which the first heat medium returning to the condenser 37 flows out. And a heat storage tank 10b (an example of a low temperature side heat storage unit). That is, the first heat medium circulation path C is disposed so that the first heat medium flowing out from the high temperature side heat storage tank 10a flows into the low temperature side heat storage tank 10b. Thereby, after heating up the 1st heat carrier with the condenser 37, it will distribute | circulate the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b in series in order of description.

  As shown in FIG. 2, the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b have a high temperature side latent heat storage material 20a that stores latent heat with phase change by heat exchange with the first heat medium, respectively, and a low temperature side latent heat. A heat storage material 20b is provided.

The melting point of the high-temperature side latent heat storage material 20a is, for example, the temperature TH of the first heat medium flowing into the high-temperature side heat storage tank 10a when the fuel cell 30 is in rated operation (in the case of a solid oxide fuel cell: 85 ° C., in the case of a polymer electrolyte fuel cell: less than 65 ° C.), the temperature is set to about 40 ° C. lower than the temperature TH of the first heat medium, and higher than the melting point of the low-temperature side latent heat storage material 20b. The temperature is set.
On the other hand, the melting point of the low-temperature side latent heat storage material 20b provided in the low-temperature side heat storage tank 10b is less than the condensation temperature of the water vapor contained in the exhaust gas E (for example, a temperature below 40 ° C.) in the condenser 37 of the fuel cell 30. The temperature TL is set.

  With the above configuration, the first heat medium circulating in the first heat medium circuit C is heated (temperature TH) by recovering the exhaust heat of the exhaust gas E by the condenser 37, and a part of the recovered heat. Is radiated (temperature TM) to the high temperature side latent heat storage material 20a in the high temperature side heat storage tank 10a, and then the remaining heat is radiated (temperature TL) to the low temperature side latent heat storage material 20b of the low temperature side heat storage tank 10b. As a result, in the high temperature side heat storage tank 10a, heat is stored at a relatively high temperature that is equal to or higher than the melting point of the high temperature side latent heat storage material 20a, and in the low temperature side heat storage tank 10b, a relatively low temperature that is equal to or higher than the melting point of the low temperature side latent heat storage material 20b. It will be stored heat.

Here, the heat transfer in the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b will be described below.
As shown in FIGS. 1 and 2, the heat transfer from the fuel cell 30 side, which is the heat supply side, in the high temperature side heat storage tank 10a is the same as that in the high temperature side heat storage tank 10a. The hot water flowing through the hot water flow passage L1 on the heat utilization side is raised to tm to th while the temperature is lowered to -TM. Therefore, the high-temperature side latent heat storage material 20a accommodated in the high-temperature side heat storage tank 10a is set to change in phase between TH, which is the highest temperature in the tank, and tm, which is the lowest temperature in the tank. .
On the other hand, the heat transfer in the low temperature side heat storage tank 10b flows through the hot water flow passage L1 on the heat utilization side in the state where the temperature of the first heat medium on the heat supply side drops to TM to TL in the low temperature side heat storage tank 10b. The hot water is heated to tl to tm. Therefore, the low-temperature side latent heat storage material 20b accommodated in the low-temperature side heat storage tank 10b is set to change in phase between TM, which is the highest temperature in the tank, and tl, which is the lowest temperature in the tank. .
As a result, the first heat medium temperature that returns to the condenser 37 that is the heat receiving portion of the first heat medium is lower than the condensation temperature (for example, 40 ° C.) of the water vapor.
As the high temperature side latent heat storage material 20a and the low temperature side latent heat storage material 20b, those shown in Table 1 below are preferably used. In the following [Table 1], for the convenience of explanation, the intermediate temperature side latent heat storage material 20c described in the second embodiment to be described later is also illustrated.

The heat stored in the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b is configured to be available for hot water supply.
In other words, a water supply port (not shown) to which pressurized water is supplied, a high temperature side heat exchanger 12 built in the high temperature side heat storage tank 10a, and a low temperature side heat exchanger 13 built in the low temperature side heat storage tank 10b. And a hot water flow passage L1 having a hot water outlet (not shown) through which hot water is discharged. After the hot water flowing through the hot water flow passage L1 is heat-exchanged with at least one of the low-temperature side latent heat storage material 20b and the first heat medium in the low-temperature side heat exchanger 13, the hot-water flows to the high-temperature side heat exchanger 12. Then, heat exchange is performed with at least one of the high-temperature side latent heat storage material 20a and the first heat medium.
After passing through the low temperature side heat exchanger 13, the hot water is heated to a temperature near the melting point of the low temperature side latent heat storage material 20b (for example, a temperature of 32 ° C. to 36 ° C.), and then the high temperature side heat exchanger 12 is changed. By passing, the temperature is raised to a temperature in the vicinity of the melting point of the high-temperature side latent heat storage material 20a (for example, a temperature of 47 ° C. to 58 ° C.), and can be effectively used as hot water.

Connection end portions of the first heat medium circulation path C connected to the high temperature side heat storage tank 10a are drilled in the upper side and the lower side in the vertical direction inside the high temperature side heat storage tank 10a. The upper connection end Cu and the lower connection end Cd extend in the horizontal direction inside the high temperature side heat storage tank 10a, and a plurality of openings Ca are provided at equal intervals along the horizontal direction. .
Thereby, the 1st heat medium which flowed into the inside of high temperature side heat storage tank 10a from opening Ca of upper part side connection end Cu spreads over the whole high temperature side heat storage tank 10a, and high temperature side latent heat storage material 20a and After exchanging heat in a form in direct contact with the high temperature side heat exchanger 12, the heat flows into the inside of the first heat medium circulation path C from the opening Ca of the lower connection end Cd.

Similarly, connection end portions of the first heat medium circulation path C connected to the low temperature side heat storage tank 10b are formed in the low temperature side heat storage tank 10b on the upper side and the lower side in the vertical direction. The upper connection end Cu and the lower connection end Cd extend in the horizontal direction inside the low temperature side heat storage tank 10b, and a plurality of openings Cb are provided at equal intervals along the horizontal direction.
Thereby, the 1st heat medium which flowed into the inside of the low temperature side heat storage tank 10b from the opening part Cb of the upper side connection end Cu diffuses over the whole low temperature side heat storage tank 10b, and the low temperature side latent heat storage material 20b and After exchanging heat in a form in direct contact with the low-temperature side heat exchanger 13, the heat flows into the first heating medium circulation path C from the opening Cb of the lower connection end Cd.

  As the first heat medium, one that does not mutually dissolve with the liquid phase latent heat storage materials 20a and 20b is employed. Thereby, the state in which the latent heat storage materials 20a and 20b do not flow out from the inside of the low temperature side heat storage tank 10b and the high temperature side heat storage tank 10a is maintained.

[Second Embodiment]
In the heat supply system 100 which concerns on the said 1st Embodiment, the structure provided with the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b as the heat storage part 10 was shown. In the heat supply system 100 according to the second embodiment, in addition to the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b, one or a plurality of medium temperature side heat storage tanks 10c (an example of an intermediate temperature side heat storage unit) are provided. Adopted.
In the following, the description will be given with an emphasis on the characteristic configuration in the second embodiment, and the same configuration as in the first embodiment in other configurations will be denoted by the same reference numerals as in the first embodiment. , Omit the explanation. Hereinafter, based on FIG. 3, the heat supply system 100 which concerns on the said 2nd Embodiment is demonstrated.
In the heat supply system 100 according to the second embodiment, as the heat storage unit 10, the high temperature side heat storage tank 10a into which the first heat medium heated by the condenser 37 flows, and the first flow out of the high temperature side heat storage tank 10a. A medium temperature side heat storage tank 10c (one in the second embodiment) into which the heat medium flows and a low temperature side from which the first heat medium flowing out from the medium temperature side heat storage tank 10c flows in and out of the heat medium returning to the condenser 37 And a heat storage tank 10b.
That is, in the second embodiment, the first heat medium raised in temperature by the heat receiving unit 37 flows through the high temperature side heat storage tank 10a, the medium temperature side heat storage tank 10c, and the low temperature side heat storage tank 10b in the order described. The first heat medium circulation path C is disposed so as to return to the heat receiving unit 37.

  Here, the high temperature side heat storage tank 10a, the medium temperature side heat storage tank 10c, and the low temperature side heat storage tank 10b are respectively provided with a high temperature side latent heat storage material 20a, a medium temperature side latent heat storage material 20c, and a low temperature side latent heat storage material 20b. As for the materials and the like, those shown in [Table 1] described above can be suitably used.

Here, when the polymer electrolyte fuel cell 30 is used as a heat source, the temperature of the exhaust gas E may decrease from 60 ° C. during rated operation to about 48 ° C. In this case, as the high temperature side latent heat storage material 20a, when the melting point is 52 ° C. or 58 ° C. as shown in [Table 1] described above, heat storage using latent heat is performed in the high temperature side heat storage tank 10a. The first heat medium cannot flow in the high temperature side heat storage tank 10a and flows to the low temperature side without being able to radiate heat.
In the heat supply system 100 of the second embodiment, the intermediate temperature side heat storage in which the intermediate temperature side latent heat storage material 20c is filled on the downstream side of the high temperature side heat storage tank 10a in the flow direction of the first heat medium circulation path C. While providing the tank 10c, the melting point of the intermediate temperature side latent heat storage material 20c is set to be lower than the lower limit temperature (for example, 48 ° C.) of the exhaust gas E discharged from the polymer electrolyte fuel cell 30. Thereby, even if it is a case where the temperature of the waste gas E of the fuel cell 30 falls from the temperature at the time of rating, the heat which the waste gas E can carry out can be latent-heat-recovered in the intermediate temperature side heat storage tank 10c.

In the said 2nd Embodiment, the hot water flow path L1 makes the pressurized water supplied from a water supply port (not shown) into the low temperature side heat exchanger 13 incorporated in the low temperature side heat storage tank 10b, and the intermediate temperature side heat storage tank 10c. It arrange | positions so that hot water may flow through the built-in intermediate temperature side heat exchanger 14 and the high temperature side heat exchanger 12 built in the high temperature side heat storage tank 10a in the order of description.
The low-temperature (tl: 15 ° C., for example) hot water supplied from the water supply port exchanges heat with at least one of the low-temperature side latent heat storage material 20b and the first heat medium in the low-temperature side heat exchanger 13. The temperature is raised to 1 intermediate temperature (tm1: 25 ° C., for example), and the intermediate temperature side heat exchanger 14 exchanges heat with at least one of the intermediate temperature side latent heat storage material 20c and the first heat medium to obtain the second intermediate temperature (tm2 The temperature is raised to, for example, 35 ° C., and the temperature is raised to a high temperature (th: for example, 45 ° C.) by exchanging heat with at least one of the high-temperature side latent heat storage material 20a and the heat medium in the high temperature side heat exchanger 12. After that, hot water is supplied from a hot water outlet (not shown).

Furthermore, in the said 2nd Embodiment, the 2nd heat medium used as the heat receiving side is circulated in the thermal storage part 10 between the thermal storage part 10 and the thermal load terminal 50 (for example, a floor heating panel or a bathroom heating dryer). The second circulation pump P2 and the heating circuit L2 are provided separately from the hot water flow passage L1.
If description is added, the said heating circuit L2 will be the 2nd heat | fever after the 2nd heat medium leaves the thermal load terminal 50 among the high temperature side heat storage tank 10a, the intermediate temperature side heat storage tank 10c, and the low temperature side heat storage tank 10b. It arrange | positions in the state which collect | recovers the heat | fever of the thermal storage part with which the latent heat storage material of melting | fusing point higher than the return temperature of a medium (further speaking, lower limit temperature of return temperature) is filled. In other words, the heating circuit L2 incorporates the second heat medium after exiting the heat load terminal 50 into the medium temperature side heat exchanger 41 built in the medium temperature side heat storage tank 10c and the high temperature side heat storage tank 10a. It arrange | positions in the state which circulates a 2nd heat medium in the order as described in the high temperature side heating heat exchanger 42.
Thereby, the low temperature (dtl: for example, 42 ° C.) second heat medium after passing through the heat load terminal 50 is changed between the intermediate temperature side latent heat storage material 20c and the first heat medium in the intermediate temperature side heating heat exchanger 41. Heat exchange with at least one of them to raise the temperature to an intermediate temperature (dtm: 46 ° C., for example), and at the high temperature side heating heat exchanger 42, at least one of the high temperature side latent heat storage material 20a and the first heat medium Heat exchange is performed to increase the temperature to a high temperature (dth: 53 ° C., for example), and the heat load terminal 50 is headed again.

Here, the heat transfer in the high temperature side heat storage tank 10a, the intermediate temperature side heat storage tank 10c, and the low temperature side heat storage tank 10b will be described below.
As shown in FIG. 3, the heat transfer in the high temperature side heat storage tank 10a is a state in which the first heat medium on the heat supply side drops in temperature to TH to TM1 (for example, 60 ° C. to 55 ° C.) in the high temperature side heat storage tank 10a. In the state where the hot water flowing through the hot water flow passage L1 on the heat utilization side is heated to tm2 to th (for example, 35 ° C. to 45 ° C.), the second flowing through the heating circuit L2 on the heat utilization side. The heating medium is performed in a state where the temperature is raised to dtm to dth (for example, 46 ° C to 53 ° C). Therefore, the high temperature side latent heat storage material 20a accommodated in the high temperature side heat storage tank 10a is set so as to change in phase between TH which is the highest temperature in the tank and tm2 or dtm which is the lowest temperature in the tank. ing.
The heat transfer in the intermediate temperature side heat storage tank 10c is performed in the state where the first heat medium on the heat supply side drops to TM1 to TM2 (for example, 55 ° C to 48 ° C) in the intermediate temperature side heat storage tank 10c. In the state where the hot water flowing through the flow passage L1 is heated to tm1 to tm2 (for example, 25 ° C. to 35 ° C.), the second heat medium flowing through the heating circuit L2 on the heat utilization side is dtl to dtm (for example, 42 to 46 ° C.). Therefore, the intermediate temperature side latent heat storage material 20c accommodated in the intermediate temperature side heat storage tank 10c is set so as to change in phase between TM1 which is the highest temperature in the tank and tm1 or dtl which is the lowest temperature in the tank. ing.
The heat transfer in the low-temperature side heat storage tank 10b is performed in the state where the first heat medium on the heat supply side drops to TM to TL (for example, 45 ° C to 28 ° C) in the low-temperature side heat storage tank 10b. The hot water flowing through the flow path L1 is heated to tl to tm1 (for example, 15 ° C to 25 ° C). Therefore, the low-temperature side latent heat storage material 20b accommodated in the low-temperature side heat storage tank 10b is set to change in phase between TM2 which is the highest temperature in the tank and tl which is the lowest temperature in the tank. .
As a result, the heat medium temperature that returns to the condenser 37 that is the heat receiving portion of the first heat medium is lower than the condensation temperature (for example, 40 ° C.) of the water vapor.

[Another embodiment]
(1) In the said embodiment, although it was set as the structure provided with the latent heat storage material 20 as a heat storage material in both the high temperature side heat storage tank 10a and the low temperature side heat storage tank 10b, water is used as a heat storage material in any one of these. And the configuration can be simplified.

(2) In the above embodiment, when the heat supply (radiation) to the heat utilization side of the low temperature side latent heat storage material 20b of the low temperature side heat storage tank 10b is not performed satisfactorily, the latent heat storage material stores the heat (for example, In the case where all of the latent heat storage material maintains the liquid phase), the temperature of the first heat medium guided from the low temperature side heat storage tank 10b to the condenser 37 side is included in the exhaust gas E by the condenser 37. It exceeds the condensation temperature (for example, 40 ° C.) at which water vapor can be condensed, and the water vapor contained in the exhaust gas E cannot be condensed properly. Therefore, in the above embodiment, a configuration in which a radiator (not shown) is provided between the low temperature side heat storage tank 10b of the first heat medium circulation path C and the condenser 37 may be adopted.
Thereby, even if it is a case where the temperature of the 1st heating medium discharged from the low temperature side heat storage tank 10b exceeds the condensation temperature, the said 1st heating medium is radiated with a heat radiator, and the temperature is made into condensation temperature. Can be reduced to less than

(3) In the above embodiment, the configuration in which the heat receiving portion is the condenser 37 of the fuel cell 30 has been described as an example. However, the heat receiving unit may be configured by an exhaust heat recovery heat exchanger that exchanges heat with engine cooling water or exhaust gas of the engine.

(4) In the second embodiment, the second heat medium circulating in the heating circuit L2 is, as shown in FIG. 4, the first heat medium flowing through the first heat medium circulation path C in the first embodiment. Similarly, you may employ | adopt the structure which can be poured into the inside of the high temperature side heat storage tank 10a and the middle temperature side heat storage tank 10c as the heat storage part 10. FIG.
If description is added, the connection end part of the heating circuit L2 connected to the high temperature side heat storage tank 10a will be vertically connected to the upper connection end part L2u provided on the upper side in the vertical direction inside the high temperature side heat storage tank 10a. The connection end portion L2d is provided on the lower side in the direction, both of which extend in the horizontal direction, and a plurality of openings are provided at equal intervals along the horizontal direction.
Moreover, the connection end part of the heating circuit L2 connected to the middle temperature side heat storage tank 10c is the upper side connection end part L2u provided on the upper side in the vertical direction inside the middle temperature side heat storage tank 10c, and the lower side in the vertical direction. It is comprised from the connection edge part L2d provided in the side, both are extended in the horizontal direction, and several opening parts are provided in the said horizontal direction at equal intervals.
In this configuration, the first heat medium and the second heat medium are made the same heat medium, and the first circulation pump P1 and the second circulation pump P2 are made to work so as to circulate the same flow rate of the heat medium. Is preferred.
By adopting the configuration, for example, in the high temperature side heat storage tank 10a, a part of the relatively high temperature first heat medium flowing from the connection end Cu on the upper side of the first heat medium circulation path C is used as a heating circuit. Since it directly flows into the connection end L2u on the upper side of L2 and is led to the thermal load terminal, it is possible to realize an operation with high thermal efficiency.
Moreover, from a viewpoint of comparison with the heat supply system 100 of the second embodiment, the middle temperature side heat storage tank 41 c is provided with the middle temperature side heating heat exchanger 41, and the higher temperature side heat storage tank 10 a is provided with the high temperature side heating heat exchange. Since the vessel 42 can be omitted, a large amount of latent heat storage material can be filled by the volume, and the heat storage capacity can be increased.

(5) In the second embodiment, the heating circuit L2 is configured so that the second heat medium recovers the heat stored in the intermediate temperature side heat storage tank 10c and recovers the heat stored in the high temperature side heat storage tank 10a. An example of arrangement is shown.
However, the heating circuit L2 may be arranged such that the second heat medium recovers only the heat stored in the high temperature side heat storage tank 10a.
In any case, the heating circuit L2 is configured to bypass the low temperature side heat storage tank 10b, and return from the thermal load terminal 50 that may return at a temperature exceeding the melting point of the low temperature side latent heat storage material 20b. The heat of the two heat mediums is prevented from being stored as the latent heat of the low-temperature side latent heat storage material 20b, thereby preventing the latent heat storage capacity from decreasing.
As a result, the heat of the first heat medium after circulating through the first heat medium circulation path C and passing through the low-temperature side latent heat storage material 20b is stored as latent heat of the low-temperature side latent heat storage material 20b. The temperature of the medium can be made lower than the condensation temperature at which the water vapor contained in the exhaust gas E is condensed by the condenser 37 at the melting point of the low-temperature side latent heat storage material 20b.

(6) In the second embodiment, an example in which one intermediate temperature side heat storage tank 10c is provided has been described, but one or more pluralities may be provided. Further, the plurality of medium temperature side heat storage tanks 10c may be provided in series in the flow direction of the first heat medium circulation path C or may be provided in parallel.

  The heat supply system of the present invention does not cause fluctuations in the pressure and flow rate of the first heat medium circulating through the heat receiving unit as the heat source while storing heat at a high density in the heat storage unit, and the heat source (for example, fuel cell) It can be effectively used as a heat supply system capable of preventing a decrease in operating efficiency.

10a: High temperature side heat storage tank 10b: Low temperature side heat storage tank 20a: High temperature side latent heat storage material 20b: Low temperature side latent heat storage material 30: Fuel cell 37: Condenser (an example of a heat receiving part)
100: Heat supply system C: Heat medium circuit E: Exhaust gas

Claims (9)

A first heat medium circulation path through which the first heat medium on the heat supply side in the heat storage unit circulates is provided between the heat receiving unit and the heat storage unit,
The heat storage part is filled with a latent heat storage material,
The heat of the first heat medium heated at the heat receiving part is configured to be able to store heat to the latent heat storage material inside the heat storage part,
A heat supply system capable of supplying heat from the heat storage section in the heat storage state to the heat utilization side using a hot water flow passage,
The first heat medium circulation path is provided so that the first heat medium can flow into the heat storage unit,
The hot water flow passage is composed of a water supply port to which pressurized water is supplied, a first heat exchanger built in the heat storage unit, and a hot water outlet for hot water.
The water flowing in from the water supply port can supply heat to the heat utilization side by exchanging heat with at least one of the latent heat storage material and the first heat medium by the first heat exchanger and flowing out to the hot water outlet. Heat supply system.   The high temperature side heat storage part into which the 1st heat medium heated at the said heat receiving part flows in as the said heat storage part, and the low temperature side heat storage part which flows out the 1st heat medium which returns to the said heat receiving part are provided. Heat supply system.   The hot water flow passage is disposed so that the hot water flowing through the hot water flow passage can recover the heat stored in the high temperature side heat storage unit after recovering the heat stored in the low temperature side heat storage unit. The heat supply system described in. In addition to the high temperature side heat storage unit and the low temperature side heat storage unit, the heat storage unit includes one or a plurality of medium temperature side heat storage units,
The first heat medium so that the first heat medium heated at the heat receiving part flows through the high temperature side heat storage part, the intermediate temperature side heat storage part, and the low temperature side heat storage part in the order described and returns to the heat receiving part. The heat supply system according to claim 2 or 3, wherein a medium circulation path is disposed.   The heat supply system according to claim 4, wherein a heating circuit that circulates a second heat medium on a heat receiving side in the heat storage unit between the heat storage unit and the thermal load terminal is provided separately from the hot water flow passage.   In the heating circuit, the second heat medium is higher than the return temperature of the second heat medium after exiting the thermal load terminal among the high temperature side heat storage unit, the intermediate temperature side heat storage unit, and the low temperature side heat storage unit. The heat supply system of Claim 5 arrange | positioned in the state which collect | recovers the heat | fever of the heat storage part with which the said latent heat storage material of high melting | fusing point is filled. The heating circuit is arranged in a state where the second heat medium recovers only the heat stored in the high temperature side heat storage unit, or in a state where only the heat stored in the high temperature side heat storage unit and the intermediate temperature side heat storage unit is recovered. Established,
The said hot water flow path is arrange | positioned so that hot water can collect | recover the heat | fever stored in the said low temperature side thermal storage part, the said intermediate temperature side thermal storage part, and the said high temperature side thermal storage part in order of the description. Heat supply system. The heat receiving part collects exhaust heat of exhaust gas generated in a heat source machine,
The heat according to any one of claims 4 to 7, wherein a melting point of the intermediate temperature side latent heat storage material filled in the intermediate temperature side heat storage unit is set to be lower than a lower limit temperature of the exhaust gas discharged from the heat source unit. Supply system. The heat receiving unit is a condenser that causes heat exchange between the exhaust gas generated in the fuel cell and the heat medium in the heat medium circulation path, and condenses water vapor contained in the exhaust gas,
The heat supply according to any one of claims 2 to 8, wherein a melting point of the low-temperature side latent heat storage material filled in the low-temperature side heat storage unit is set to be lower than a condensation temperature for condensing water vapor contained in the exhaust gas. system.

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