JP6477249B2 - Heat storage system - Google Patents

Description

  The present invention relates to a heat storage system used for heat storage.

  Power generation facilities that use natural energy, such as solar thermal power generation, solar power generation, and wind power generation, should be equipped with a heat storage system to suppress transient changes in output power caused by changes in sunshine conditions and weather conditions. Has been done.

  As this type of heat storage system, for example, a heat storage tank is filled with a heat storage material that causes a phase change between a solid phase and a liquid phase in a heat storage temperature range, and heat storage is performed using the latent heat of this heat storage material, The thing which aimed at the improvement of a thermal storage density is conventionally known.

Examples of the heat storage material that causes a phase change between the solid phase and the liquid phase in the heat storage temperature range include CsNO ₃ and NaNO ₃ , LiNO ₃ and LiOH, LiNO ₃ and NaNO ₃ , KNO ₃ and NaNO ₃ , NaNO ₃ and Conventionally, it has been proposed to use a heat storage material made of a mixed salt having a non-eutectic composition of two components such as RbNO ₃ , LiBr and LiOH, and LiBr and NaNO ₃ (see, for example, Patent Document 1).

  Furthermore, for a hot water heat storage device that is one of the heat storage devices, a heat exchanger that circulates the hot water and performs heat exchange with the latent heat storage material, a plurality of branch paths that communicate the inlet and outlet of the hot water, The idea of a configuration with a plurality of on-off valves is shown. Furthermore, this heat exchanger can switch the path through which the hot water is circulated between a parallel path having a large hot water passage area and a short passage length, and a series path having a small hot water passage area and a long passage length. (For example, see Patent Document 2).

International Publication No. 2014/185179 JP 2003-294322 A

  By the way, in general, depending on the type of heat load that supplies a heat medium and uses the heat, it may be desired to supply a heat medium that is as stable as possible.

  On the other hand, in the heat storage tank, the temperature of the heat storage material changes when the amount of heat storage changes. Therefore, when supplying a heat-dissipating heat medium at a constant temperature and causing heat dissipation from the heat storage material by heat exchange with the heat-dissipating heat medium, the heat storage material and the heat-dissipating heat medium Therefore, the heat transfer rate changes depending on the temperature difference. Thereby, since the heat dissipation rate when the conventional heat storage tank radiates heat from the heat storage material to the heat dissipation heat medium changes, the temperature of the heat dissipation heat medium recovered from the heat storage tank after heat exchange with the heat storage material is It changes according to the amount of heat stored in the heat storage tank.

  Note that the heat exchanger shown in Patent Document 2 has a path through which hot water flows, a parallel path having a large hot water passage area and a short passage length, and a series path having a small hot water passage area and a long passage length. However, there is not much difference in the size of the heat transfer area where heat is exchanged between the hot water and the latent heat storage material.

  Moreover, Patent Document 2 does not show the idea of providing an on-off valve for each branch pipe, or the idea of suppressing the temperature change of the hot water that is a heat-dissipating heat medium even when the temperature of the latent heat storage material of the latent heat storage unit changes. It has not been.

  Therefore, the present invention aims to stabilize the temperature of the heat-dissipating heat medium that is recovered after heat exchange with the heat-storing material while circulating the heat-dissipating heat transfer tubes of the heat-storage tank even if the heat storage amount of the heat-storage tank changes. It is intended to provide a heat storage system that can.

  In order to solve the above problems, the present invention circulates a heat storage tank, a heat storage material put in the heat storage tank, and a heat-dissipating heat medium having a temperature lower than that of the heat storage material in the heat storage tank. A plurality of heat-dissipating heat transfer tubes that perform heat exchange with the heat storage material, a plurality of valves that switch supply and stop of the heat-dissipating heat medium to the heat dissipating heat transfer tubes, and provided in the heat storage tank, Based on the input from the heating means for heating the heat storage material for heat storage, the means for determining the temperature of the heat dissipation heat medium recovered after flowing through the heat dissipation heat transfer tube, the valve The heat storage system has a configuration including a control device that gives individual control commands to the control unit.

  The heat storage material causes a solid-liquid phase change in the heat storage temperature range of the heat storage tank, and the heat storage tank includes the heat-dissipating heat transfer tube near the upper part of the internal space containing the heat storage material, The heating means is provided on the bottom side of the space.

  Each heat transfer heat transfer tube, which is switched between supply and stop of supply of the heat dissipation heat medium by the valves, is arranged in the horizontal direction in the internal space of the heat storage tank.

  Each heat-transfer heat transfer tube that is switched between supply and stop of supply of the heat-dissipation heat medium by the valves is configured to individually include solid-phase stripping means.

  According to the heat storage system of the present invention, even if the heat storage amount of the heat storage tank changes, the temperature of the heat-dissipating heat medium recovered after circulating the heat transfer pipe for heat dissipation of the heat storage tank and exchanging heat with the heat storage material is stabilized. Can be achieved.

The 1st Embodiment of a thermal storage system is shown, (a) is a schematic cut | disconnection side view, (b) is an AA direction arrow directional view of (a). It is a figure for demonstrating the thermal radiation process of the thermal storage system of 1st Embodiment, (a) (b) (c) is a figure which shows a state when the temperature of the thermal medium for thermal radiation collect | recovered from a thermal storage tank differs, respectively. It is a figure corresponding to (b). The 1st application example of 1st Embodiment is shown, (a) is a general | schematic cutting side view, (b) is a BB direction arrow directional view of (a), (c) is CC of (a). FIG. It is a schematic diagram which shows the 2nd application example of 1st Embodiment. It is a schematic diagram which shows the 3rd application example of 1st Embodiment. The another example of arrangement | positioning of the heat exchanger tube for thermal radiation in a thermal storage system is shown, (a) is a schematic cut | disconnection side view, (b) is a DD direction arrow directional view of (a).

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
[First Embodiment]

  1A and 1B show a first embodiment of a heat storage system, in which FIG. 1A is a schematic cut side view, and FIG. 1B is a view in the direction of arrows AA in FIG. FIG. 2 shows a state during heat dissipation of the heat storage system of the present embodiment. FIG. 2 (a) shows a case where the heat storage amount of the heat storage tank is large, and FIG. 2 (b) shows that the heat storage amount is medium. (C) is a figure corresponding to FIG.1 (b) which respectively shows the case where the amount of heat storage is small.

  As shown in FIGS. 1A and 1B, the heat storage system of the present embodiment performs heating for heat storage on the heat storage tank 1, the heat storage material 2 put in the heat storage tank 1, and the heat storage material 2. Means 3 and a plurality of heat radiation heat transfer tubes 4a, 4b, 4c connected in parallel to allow heat exchange between the heat storage material 2 and the heat radiation heat medium 5 by circulating the heat radiation heat medium 5 are provided. It is configured. In FIG. 1B, for convenience of illustration, a configuration including three systems of heat transfer tubes 4a, 4b, and 4c for heat radiation is shown.

  The upstream side of each heat radiating heat transfer pipe 4a, 4b, 4c is connected to a common distribution pipe 6 via individual valves 7a, 7b, 7c. The distribution pipe 6 is connected to an external heat-dissipating heat medium supply means (not shown) through a heat-dissipating heat medium supply line 8. Thereby, the heat-dissipating heat medium 5 supplied to the distribution pipe 6 from the heat-dissipating heat medium supplying means through the heat-dissipating heat medium supply line 8 is the open valves 7a, 7b among the valves 7a, 7b, 7c. , 7c are supplied to the heat radiating heat transfer tubes 4a, 4b, 4c.

  The downstream side of each heat radiating heat transfer tube 4 a, 4 b, 4 c is connected to a common collecting tube 9. The collecting pipe 9 is connected to the upstream side of the heat-dissipating heat medium delivery line 10 that sends the heat-dissipating heat medium 5 after flowing through the heat-dissipating heat transfer pipes 4a, 4b, and 4c to the desired heat load X. As a result, the heat-dissipating heat medium 5 after flowing through the heat-dissipating heat transfer tubes 4a, 4b, 4c is once collected in the collecting pipe 9, mixed in the collecting pipe 9, and then passed through the heat-dissipating heat medium delivery line 10. Sent to thermal load X. The heat dissipation heat medium 5 after supplying heat to the heat load X may or may not be returned to the heat dissipation heat medium supply means.

  Furthermore, the heat storage system of this embodiment is provided in the heat-dissipating heat medium delivery line 10, for example, as means for obtaining the temperature of the heat-dissipating heat medium 5 collected after flowing through the heat-radiating heat transfer tubes 4a, 4b, 4c. And a control device 12 for giving individual control commands to the valves 7a, 7b, 7c based on the input from the temperature measuring device 11.

In the heat storage system of this embodiment, the heat storage material 2 put into the heat storage tank 1 causes a phase change between a solid phase and a liquid phase in a set heat storage temperature range (T _min <T <T _max ), for example, In addition, the heat storage material 2 in which the density of the solid phase is larger than the density of the liquid phase is used. In FIG. 1, the solid phase of the heat storage material 2 is shown with hatching. The details of the heat storage material 2 will be described later.

  The volume of the heat storage tank 1 is appropriately set according to the heat storage capacity desired for the heat storage tank 1, the type of the heat storage material 2, and the like.

  The heat storage tank 1 is configured as follows in consideration of the characteristics of the heat storage material 2 described above.

  The heating means 3 is provided as a hot plate at the bottom of the internal space of the heat storage tank 1 that houses the heat storage material 2. The heating means 3 includes, for example, a plate member 13 for forming the bottom surface of the internal space of the heat storage tank 1 as a flat surface, and a heat medium that circulates the heating heat medium 15 provided below the plate member 13. The flow path 14 is provided.

  The plate member 13 is configured so that the solid phase of the heat storage material 2 generated and settled in the tank when the temperature of the heat storage tank 1 is lowered is dispersed and deposited on the upper side of the plate member 13, and the load of this deposit is This is because it is preferably received in a distributed manner on the surface of the plate member 13. The heating means 3 includes upper and lower columnar and wall-like members for transmitting and supporting the load of deposits acting on the plate member 13 to the lower part of the heat medium flow path 14 below the plate member 13. You may do it.

  The heat medium passage 14 is arranged and shaped in the flow path of the heating medium 15 in the plane of the plate member 13 so that the entire surface of the plate member 13 can be heated as evenly as possible by the heat of the heating medium 15. The channel cross-sectional area and the like are set as appropriate. In FIG. 1, for convenience of illustration, the heat medium flow path 14 is simplified. Therefore, the heat medium flow path 14 may of course have any setting other than those shown in the drawing, such as the arrangement, shape, and cross-sectional area of the flow path.

  A heating heat medium supply line 16 that leads the heating heat medium 15 from an external heating heat medium supply means (not shown) is connected to the inlet side of the heat medium flow path 14.

  Further, a heating heat medium return line 17 for returning the heating heat medium 15 after flowing through the heat medium flow path 14 to the heating heat medium supply means is connected to the outlet side of the heat medium flow path 14. . Furthermore, the heating medium supply means is configured to include a heat exchanging unit for supplying the heating medium 15 with heat from a heat source (not shown) such as a heat collecting unit of solar thermal power generation for heating. Yes.

As the heating heat medium 15, a heat medium that is in a liquid phase up to the entire heat storage temperature range (T _min <T <T _max ) or higher than that is selected and used, or steam is used. What should I do? Since the temperature of the steam can be easily adjusted by adjusting its pressure, the temperature of the heating means 3 can be easily adjusted by using the steam as the heating heat medium 15.

  Thereby, the heated heating medium 15 can be circulated and supplied to the heating medium flow path 14 of the heating unit 3 from the heating medium supply unit. Therefore, in the heating means 3, the heat storage material 2 in the heat storage tank 1 can be heated from below through the plate member 13 by the heat of the heating heat medium 15 sequentially supplied to the heat medium flow path 14. .

  The heating means 3 having such a configuration uses the heat held by the heating heat medium 15 as a heat source for heating the heat storage material 2 for storing heat. For this reason, the heat storage system of this embodiment is applied to a power generation facility that uses natural energy to obtain high-temperature heat, such as solar thermal power generation, among the power generation facilities that use natural energy, and surplus heat. It is suitable when storing heat.

  The heating means 3 of the heat storage tank 1 may be an electric heater. In this case, the heat storage system of the present embodiment is applied to a power generation facility that directly generates electricity using natural energy, such as solar power generation or wind power generation, among power generation facilities using natural energy. Thus, it is suitable for storing surplus power as heat.

  The heat transfer tubes 4a, 4b, and 4c for heat radiation are provided at positions near the upper portion of the internal space of the heat storage tank 1 in an arrangement aligned in the horizontal direction as shown in FIG. ing. In addition, the arrangement | sequence arranged in a horizontal direction said here should just be arrange | positioned so that the heat exchanger tubes 4a, 4b, 4c for heat radiation may be arranged in a substantially horizontal direction, and the heat transfer tubes 4a, 4b, 4c for heat radiation are the upper and lower sides. Some deviation is allowed.

  The heat radiating heat transfer tubes 4a, 4b, and 4c are supported from the wall surface and ceiling portion of the heat storage tank 1 through a support member (not shown). It is preferable that the heat radiating heat transfer tubes 4 a, 4 b, 4 c be arranged as high as possible in the vertical direction half of the internal space of the heat storage tank 1 as much as possible within the range where the heat storage material 2 is entirely immersed. This is for preventing the phenomenon that the solid phase of the heat storage material 2 solidified around the heat transfer tubes 4a, 4b, 4c for heat dissipation settles in the liquid phase, as will be described later. However, depending on the pipe shape and overall size of the heat transfer tubes 4a, 4b, 4c for heat dissipation, the portions located on the lower end side of the heat transfer tubes 4a, 4b, 4c for heat dissipation are located above and below the internal space of the heat storage tank 1. Of course, it may be partially arranged at a height position half of the direction or at a position lower than that.

  The upstream and downstream sides of the heat transfer tubes 4a, 4b, and 4c for heat dissipation pass through the side wall 1a of the heat storage tank 1 and protrude to the outside, and the protruding ends on the upstream side connect the valves 7a, 7b, and 7c. And the downstream projecting ends are connected to the collecting pipe 9.

As the heat dissipation heat medium 5, a liquid heat medium may be selected and used, or steam may be used. In the heat storage system of this embodiment, as will be described later, the valves 7a, 7b, and 7c are opened and closed as necessary during operation. Therefore, the heat-dissipating heat transfer tubes 4a, 4b, and 4c connected to the valves 7a, 7b, and 7c that are operated to close the heat-dissipating heat medium 5 stay in the tubes. Therefore, the heat-dissipating heat medium 5 receives the heat held by the heat storage material 2 while staying in the heat-radiating heat transfer tubes 4a, 4b, and 4c, but it is necessary that the properties be stable even in this state. Is done. Therefore, the heat dissipation heat medium 5 is made of a material whose properties are stable even at the maximum heat storage temperature T _max in the heat storage temperature range (T _min <T <T _max ) set in the heat storage tank 1.

  Thereby, the heat-dissipating heat medium 5 is transferred from the distribution pipe 6 to the heat-dissipating heat transfer tubes 4a, 4b, 4c on the downstream side of the valves 7a, 7b, 7c, which are opened, among the valves 7a, 7b, 7c. Continuously supplied. The heat-dissipating heat medium 5 supplied to the heat-dissipating heat transfer tubes 4a, 4b, 4c is present around the heat-dissipating heat transfer tubes 4a, 4b, 4c while flowing through the heat-dissipating heat transfer tubes 4a, 4b, 4c. Heat is exchanged sequentially by heat exchange with the heat storage material 2 and is collected in the collecting tube 9 in a heated state. The heat dissipating heat medium 5 collected in the collecting pipe 9 is supplied to the heat load X through the heat dissipating heat medium delivery line 10 so that the heat held by the heat dissipating heat medium 5 is given to the heat load X. .

  Thus, the heat-dissipating heat medium 5 flowing through the heat-radiating heat transfer tubes 4a, 4b, 4c is heated by heat exchange with the heat storage material 2 existing around the heat-radiating heat-transfer tubes 4a, 4b, 4c. Sometimes, the temperature of the heat storage material 2 existing around the heat transfer tubes 4a, 4b, and 4c for heat radiation is relatively lowered. When the temperature drop of the heat storage material 2 occurs at the phase change temperature between the liquid phase and the solid phase, as shown in FIG. 1 (a), the heat storage material 2 is disposed around the heat transfer tubes 4a, 4b, and 4c for heat radiation. A solid phase is formed by solidifying from the liquid phase. Since the solid phase of the heat storage material 2 has a higher density than the liquid phase, it settles in the liquid phase.

  Since the heat storage tank 1 has a structure in which the heat transfer tubes 4a, 4b, 4c are provided near the upper portion of the internal space, the heat storage material 2 having a lowered temperature around the heat transfer tubes 4a, 4b, 4c is fixed. Even if a phase is generated, this solid phase settles in the inner space of the heat storage tank 1 to the bottom and is deposited on the upper side of the heating means 3.

  Therefore, in the heat storage tank 1, since the solid phase of the heat storage material 2 does not remain around the heat transfer tubes 4a, 4b, and 4c for heat dissipation, the heat dissipation that flows through the heat storage material 2 and the heat transfer tubes 4a, 4b, and 4c for heat dissipation. It is suppressed that the efficiency of heat transfer between the heat storage medium 5 is reduced due to the presence of the solid phase of the heat storage material 2.

  As shown in FIGS. 1A and 1B, the side wall 1a of the heat storage tank 1 is preferably provided with a side wall heater 18 for increasing the temperature of the side wall 1a.

  The side wall heater 18 is provided so as to reach the height position of a half in the vertical direction of the internal space from the lower end of the internal space of the heat storage tank 1. The side wall heater 18 is preferably provided over the entire circumference of the side wall 1a. 1A and 1B, the side wall heater 18 may be provided along the inner surface of the side wall 1a, although not shown, in addition to the configuration provided on the outer surface of the side wall 1a. Further, although not shown, the side wall heater 18 may be provided over the entire range in the vertical direction in which the heat storage material 2 in the internal space of the heat storage tank 1 is stored.

  As the side wall heater 18, for example, an electric heater may be used. Or the heater 18 for side walls is good also as a heater of the structure provided with the heat-medium flow path which distribute | circulates steam and another liquid-phase heat medium similarly to the heating means 3. FIG.

  Further, the side wall heater 18 is set so that the side wall 1 a is also heated by the side wall heater 18 when the heat storage material 2 is heated by the heating means 3, that is, when heat is stored in the heat storage tank 1.

  The heating temperature of the side wall 1a by the side wall heater 18 may be set to a temperature at which the heat storage material 2 changes from a solid phase to a liquid phase.

  Thereby, at the time of the heating by the heating means 3, the solid phase of the heat storage material 2 deposited on the upper side of the heating means 3 is heated from below, and first melts from the portion in contact with the upper surface of the heating means 3 to be liquid Become a phase.

  At this time, by operating the side wall heater 18 together, the solid phase of the heat storage material 2 existing in the vicinity of the inner surface of the side wall 1a is melted into a liquid phase. For this reason, the solid phase deposit of the heat storage material 2 is eliminated from the inner surface of the side wall 1a. Further, the liquid phase of the heat storage material 2 generated at the portion in contact with the upper surface of the heating means 3 flows at a position along the inner periphery of the side wall 1 a and moves above the solid deposit of the heat storage material 2.

  As a result, in the heat storage tank 1, the solid-phase deposit of the heat storage material 2 can be pressed against the upper surface of the heating means 3 by its own weight, and at that time, it is formed between the upper surface of the heating means 3 and the deposit. The liquid phase layer of the heat storage material 2 can be thinned. Thereby, the efficiency of heat transfer from the heating means 3 to the solid phase of the heat storage material 2 can be increased.

  Furthermore, even if volume expansion occurs with the phase change from the solid phase to the liquid phase in the heat storage material 2 existing in the portion in contact with the upper surface of the heating means 3, the volume change is the liquid storage material 2 liquid. It can be easily absorbed by moving the phase above the solid phase. Therefore, the possibility that an excessively large pressure acts on the side wall 1a or the entire heat storage tank 1 when the heat storage material 2 is heated is prevented.

Furthermore, due to an unexpected situation, even if the entire heat storage tank 1 is lowered in temperature from the heat storage temperature range (T _min <T <T _max ), and the heat storage material 2 is all in a solid phase. By operating the heater 18 for the side wall, it is possible to raise the temperature in the heat storage tank 1 and return it to the heat storage temperature range while melting the heat storage material 2 in a wide range in the vertical direction.

  Next, the heat storage material 2 will be described.

  The heat storage material 2 that solidifies around the heat transfer tubes 4a, 4b, 4c for heat dissipation when the heat stored in the heat storage material 2 is dissipated using the heat dissipation heat medium 5 flowing through the heat transfer tubes 4a, 4b, 4c. If the solid phase adheres to the surface of the heat transfer tubes 4a, 4b, 4c for heat radiation, the heat transfer efficiency is lowered due to the presence of the solid phase of the heat storage material 2.

As a result of research on countermeasures against such a decrease in heat transfer efficiency, as shown in Patent Document 1, it is difficult for the solid phase of the heat storage material 2 to adhere to the surfaces of the heat transfer tubes 4a, 4b, 4c for heat radiation. to as thermal storage material 2, the use of those made from the heat storage temperature range _{(T min <T <T max} ) 2 -component mixed salt of a non-eutectic composition as the solid-liquid coexisting state at the heat storage minimum temperature _{T min} of Has been found to be advantageous.

For example, when assuming application to a high-temperature system such as solar thermal power generation, the minimum heat storage temperature T _{min in} the heat storage temperature range (T _min <T <T _max ) desired for the heat storage system is 150 ° C. or higher, preferably 200 ℃ or more.

Therefore, as an example, the heat storage temperature range (T _min <T <T _max ) of the heat storage tank 1 in the heat storage system of the present embodiment is set such that the maximum heat storage temperature T _max is 400 ° C. and the minimum heat storage temperature T _min is 250 ° C. An example of this is shown below.

As a heat storage material 2 suitable for this condition, for example, potassium nitrate (KNO ₃ ) and sodium nitrate (NaNO ₃ ) are used in combination of the binary mixed salt shown in Patent Document 1 as a non-co-polymer. There is a binary mixed salt mixed in a composition that forms crystals.

In this mixture of potassium nitrate and sodium nitrate, a eutectic is formed with a composition in which the molar fraction of sodium nitrate is 0.49. Therefore, a composition other than the composition that becomes the eutectic is used, and the heat storage minimum temperature T _min is 250. A solid-liquid coexistence state is established at ° C. As a specific composition example, an example in which a composition having a molar fraction of sodium nitrate of 0.786 (mass fraction of 0.755) is used as the heat storage material 2 will be described.

The heat storage material 2 is only in the liquid phase at 400 ° C., which is the maximum heat storage temperature T _max , and when it is gradually cooled from this state, a solid phase is generated at 274 ° C. When the heat storage material 2 is further cooled, the temperature decreases to 250 ° C., which is the minimum heat storage temperature T _min , while the ratio of the solid phase gradually increases. During this cooling, the heat storage material 2 generates a solid phase on the surface of the heat radiating heat transfer tubes 4a, 4b, 4c having the lowest temperature, and the solid phase grows along the surface of the heat radiating heat transfer tubes 4a, 4b, 4c. However, since the solid phase is difficult to adhere to the surfaces of the heat transfer tubes 4a, 4b, and 4c for heat radiation, the solid phase is peeled off by the flow of the heat storage material 2 or the like. In addition, if the heat storage material 2 is further cooled from 250 _degreeC which is the heat storage minimum temperature _Tmin , the whole heat storage material 2 will be in a solid phase at 234 degreeC.

Therefore, in the heat storage tank 1 using the heat storage material 2, the sensible heat of the heat storage material 2 and the heat storage material 2 melt from the solid phase in the temperature range from 250 ° C. to 274 ° C. of the minimum heat storage temperature T _min. Heat storage is performed by the latent heat at the time of phase, and heat storage is performed by sensible heat of the heat storage material 2 in a temperature range of 274 ° C. to 400 ° C. from the maximum heat storage temperature T _max .

In addition, as the heat storage material 2, when the maximum heat storage temperature T _max is set to 400 ° C. and the minimum heat storage temperature T _min is set to 250 ° C. as described above, the mixture of the two components shown in Patent Document 1 is used. Of the salt combinations, for example, a mixture of CsNO ₃ and NaNO _3, a mixture of LiNO ₃ and NaNO _{3, and} a mixture of NaNO ₃ and RbNO ₃ can be used.

When a mixture of CsNO ₃ and NaNO ₃ is used, the molar fraction of NaNO ₃ is 0.902 (mass fraction is 0.801), and when a mixture of LiNO ₃ and NaNO ₃ is used, the molar fraction of NaNO ₃ When the ratio is 0.877 (mass fraction is 0.898) and a mixture of NaNO ₃ and RbNO ₃ is used, the molar fraction of RbNO ₃ is 0.105 (mass fraction is 0.169). Thus, a solid-liquid coexistence state can be obtained at 250 ° C., which is the lowest heat storage temperature T _min .

Further, when the minimum heat storage temperature T _{min in} the heat storage temperature range (T _min <T <T _max ) is set to 280 ° C., the heat storage material 2 is a mixture of two components shown in Patent Document 1 above. Of the salt combinations, it is possible to use a mixture of LiBr and NaNO ₃ . In this case, by setting the molar fraction of NaNO ₃ to 0.964 (mass fraction of 0.963), a solid-liquid coexistence state can be _achieved at 280 ° C., which is the lowest heat storage temperature T _min .

  When a binary mixed salt having a non-eutectic composition as described above is used as the heat storage material 2, the solid phase of the heat storage material 2 generated by solidification around the heat transfer tubes 4a, 4b, 4c for heat dissipation becomes a cooling surface. It does not adhere strongly to the surface of the heat transfer tubes 4a, 4b, 4c, which are heat transfer surfaces, and easily comes off.

  This is because the solid fraction near the cooling surface increases locally when it begins to solidify, so that the molten salt forming a liquid phase with a relatively low melting point enters between the cooling surface and the solid phase. This is thought to be due to the progress of solidification, and is attributed to the existence of a solid-liquid coexistence region of non-eutectic molten salt with a temperature range.

  Therefore, the heat storage system of the present embodiment performs control in the heat storage tank 1 so that the solid phase gradually increases from the liquid phase state of the heat storage material 2, that is, the temperature is gradually decreased. It becomes possible to suppress that the heat storage material 2 that has become a solid phase adheres (adheres) to the surface of the heat transfer tubes 4a, 4b, 4c for heat radiation.

  Since the temperature measuring instrument 11 is provided in the heat-dissipating heat medium delivery line 10, it is once collected in the collecting tube 9 after flowing through the heat-dissipating heat transfer tubes 4 a, 4 b, 4 c, and then the heat-dissipating heat medium delivery line 10. The temperature of the heat-dissipating heat medium 5 sent to the heat load X through can be directly measured.

  Next, the heat dissipation process by the heat storage system of the present embodiment will be described along the description of the function of the control device 12.

  First, the control device 12 sets a desired temperature (hereinafter referred to as “sending heat medium temperature T0”) for the heat dissipating heat medium 5 sent to the heat load X. For example, as described above, when the heat storage temperature range of the heat storage tank 1 is 250 ° C. to 400 ° C. and the temperature of the heat dissipation heat medium 5 before being supplied to the heat storage tank 1 is 200 ° C., the delivery heat medium temperature T0 Is set to 250 ° C. At this time, it is preferable to set an allowable amount of temperature deviation in the control device 12 such as 250 ° C.-α ° C. with respect to the delivery heat medium temperature T0. As will be described later, when the number of heat-dissipating heat transfer tubes 4a, 4b, 4c supplying the heat-dissipating heat medium 5 is changed, the heat-transfer area in which the heat-dissipating heat medium 5 and the heat storage material 2 exchange heat is stepwise. This is because it is difficult to continuously control the temperature of the heat dissipating heat medium 5.

It should be noted that the heat transfer medium temperature T0 is the same as the heat transfer tube for heat dissipation, in the state where the heat storage tank 1 is at the maximum heat storage temperature ( _Tmax = 400 ° C.). When circulating through one of 4a, 4b, and 4c, the temperature of the heat-dissipating heat medium 5 sent to the heat load X is set to be the sending heat medium temperature T0.

  When the control device 12 performs the heat dissipation process by the heat storage system of the present embodiment, when the temperature measurement value of the heat dissipation heat medium 5 is input from the temperature measuring device 11, the temperature measurement value and the temperature of the heat transfer medium to be delivered at a certain time interval. A function of obtaining an opening / closing command to the valves 7a, 7b, and 7c is obtained when a difference from T0 is obtained and the difference exceeds a set temperature fluctuation range (± α ° C.).

Specifically, when the heat storage tank 1 starts the heat radiation process from the state of the maximum heat storage temperature (T _max = 400 ° C.), the controller 12, as shown in FIG. Only one of 4b and 4c, for example, the valve 7a corresponding to the heat transfer tube 4a for heat dissipation is opened, and the other valves 7b and 7c are closed. In FIGS. 2A, 2B, and 2C, the valves 7a, 7b, and 7c are shown as white in the open state and black in the closed state.

  In this state, the entire amount of the heat dissipating heat medium 5 supplied from the heat dissipating heat medium supplying means is supplied from the distribution pipe 6 to the heat dissipating heat transfer pipe 4a. Therefore, the heat-dissipating heat medium 5 is subjected to heat exchange with the heat storage material 2 at 400 ° C. while flowing through the heat-dissipating heat transfer tube 4a, and is heated to 250 ° C., which is the sending heat medium temperature T0. It is collected in the collecting pipe 9 and then supplied to the heat load X through the heat dissipation heat medium delivery line 10.

  At this time, a temperature measurement value of 250 ° C. of the heat dissipation heat medium 5 is input to the control device 12 from the temperature measuring device 11.

  As described above, when the heat dissipation process is continuously performed in a state where the heat dissipation heat medium 5 is circulated through the single heat dissipation heat transfer tube 4a, the temperature of the heat storage material 2 gradually decreases. For this reason, since the temperature difference between the heat storage material 2 and the heat-dissipating heat medium 5 flowing through the heat-dissipating heat transfer tube 4a is gradually reduced, the heat transfer performance is reduced, and the heat dissipation rate from the heat storage material 2 to the heat-dissipating heat medium 5 is reduced. Decreases. Therefore, the temperature of the heat-dissipating heat medium 5 collected after passing through the heat-dissipating heat transfer tube 4a gradually decreases, so that the temperature measurement value of the heat-dissipating heat medium 5 input from the temperature measuring device 11 to the control device 12 is also 250. It gradually decreases from ℃.

  Thereafter, for example, when the temperature of the heat storage material 2 is lowered to 350 ° C., and the temperature measurement value of the heat dissipation heat medium 5 by the temperature measuring device 11 is lowered to less than 250 ° C.−α ° C., the control device 12 Based on the input from the measuring instrument 11, an opening operation command is given to one of the valves 7b and 7c that have been closed until then, for example, the valve 7b, and as shown in FIG. The valve 7b is opened.

  Thereby, the heat dissipation heat medium 5 supplied from the heat dissipation heat medium supply means to the distribution pipe 6 is distributed and supplied to the two heat dissipation heat transfer tubes 4a and 4b, and the two heat dissipation heat transfer tubes are supplied. During the circulation of 4a and 4b, heat exchange with the heat storage material 2 at 350 ° C. is performed.

  In this case, the heat transfer area in which the heat-dissipating heat medium 5 exchanges heat with the heat storage material 2 is doubled compared to when heat transfer is performed with only one heat-dissipating heat transfer tube 4a at the start of heat-dissipating treatment. The Therefore, even if the temperature difference between the heat storage material 2 and the supplied heat-dissipation heat medium 5 is smaller than that at the start of the heat-dissipation process and the heat transfer performance is reduced, the heat storage material 2 and the heat-dissipation heat medium 5 The heat dissipation rate can be increased.

  Thereby, the temperature of the heat-dissipating heat medium 5 collected after passing through the heat-radiating heat transfer tubes 4a and 4b rises to 250 ° C., for example. In this case, the temperature measurement value of the heat dissipating heat medium 5 input to the control device 12 from the temperature measuring device 11 is also recovered to 250 ° C.

  Subsequently, when the heat dissipation process is continuously performed in a state where the heat dissipation heat medium 5 is circulated through the two heat dissipation heat transfer tubes 4a and 4b, the temperature of the heat storage material 2 gradually decreases. For this reason, since the temperature difference between the heat storage material 2 and the heat-dissipating heat medium 5 flowing through the heat-dissipating heat transfer tubes 4a and 4b becomes smaller, the heat transfer performance is lowered, and the heat-transfer material 2 to the heat-dissipating heat medium 5 is reduced. The heat dissipation rate is further reduced. Therefore, the temperature of the heat-dissipating heat medium 5 collected after passing through the heat-dissipating heat transfer tubes 4a and 4b gradually decreases, so the temperature measurement value of the heat-dissipating heat medium 5 input from the temperature measuring device 11 to the control device 12 The temperature gradually decreases from 250 ° C.

  Thereafter, for example, when the temperature of the heat storage material 2 is lowered to 300 ° C., if the temperature measurement value of the heat dissipation heat medium 5 by the temperature measuring instrument 11 is lowered to less than 250 ° C.−α ° C., the control device 12 Based on the input from the measuring instrument 11, an opening operation command is given to the valve 7c that has been closed until then, and the valve 7c is opened as shown in FIG.

  As a result, the heat dissipation heat medium 5 supplied from the heat dissipation heat medium supply means to the distribution pipe 6 is distributed and supplied to the three heat dissipation heat transfer tubes 4a, 4b, 4c. Heat exchange with the heat storage material 2 at 300 ° C. is performed while flowing through the heat transfer tubes 4a, 4b, and 4c.

  In this case, the heat transfer area in which the heat-dissipating heat medium 5 exchanges heat with the heat storage material 2 is expanded by a factor of three compared to when heat transfer is performed with only one heat-dissipating heat transfer tube 4a at the start of heat-dissipating treatment. The Therefore, even if the temperature difference between the heat storage material 2 and the supplied heat-dissipation heat medium 5 is smaller than that at the start of the heat-dissipation process and the heat transfer performance is reduced, the heat storage material 2 and the heat-dissipation heat medium 5 The heat dissipation rate can be increased.

  Thereby, the temperature of the heat-dissipating heat medium 5 collected after passing through the heat-radiating heat transfer tubes 4a, 4b, 4c rises to 250 ° C., for example. In this case, the temperature measurement value of the heat dissipating heat medium 5 input to the control device 12 from the temperature measuring device 11 is also recovered to 250 ° C.

  Thereafter, the heat dissipation process is performed in a state where the heat dissipation heat medium 5 is circulated through the three heat dissipation heat transfer tubes 4a, 4b, and 4c.

  Therefore, according to the heat storage system of this embodiment, even if the temperature of the heat storage material 2 changes with a change in the amount of heat stored in the heat storage tank 1, the heat storage material 2 is circulated to exchange heat with the heat storage material 2. By controlling the number of heat transfer tubes 4a, 4b, and 4c for heat dissipation, the temperature change of the heat dissipation heat medium 5 recovered after the heat exchange with the heat storage material 2 can be changed to 250 ° C-α ° C over a long period of time. Can be kept in the range. Therefore, the heat storage system of the present embodiment can stabilize the temperature of the heat dissipation heat medium 5 collected after heat exchange with the heat storage material 2, and the temperature of the heat dissipation heat medium 5 supplied to the heat load X can be achieved. Can be stabilized.

  When heat is stored in the heat storage system of the present embodiment that has been subjected to heat dissipation processing, the heat is supplied to the heat medium flow path 14 of the heating means 3 from the heating heat medium supply means through the heating heat medium supply line 16. The heating heat medium 15 may be circulated. Thereby, the heat storage material 2 in the heat storage tank 1 is heated by the heating heat medium 15. This heat storage heat treatment may be performed when there is surplus energy such as heat or electric power.

In addition, this heat storage heat processing does not necessarily need to be performed continuously until the heat storage tank 1 reaches the maximum heat storage temperature _Tmax depending on the presence or absence of surplus energy and the demand for heat radiation.

  For example, in the case where the heat dissipation process is started from the state where the temperature of the heat storage material 2 is heated to 350 ° C. by the heat storage process, when the heat dissipation process is started, as shown in FIG. 11 is less than 250 ° C.-α ° C. Therefore, in this case, the control device 12 starts the heat dissipation process with the valve 7b opened as well as the valve 7a based on the input from the temperature measuring device 11.

[First Application Example of First Embodiment]
3A and 3B show a first application example of the first embodiment, in which FIG. 3A is a schematic cut side view, FIG. 3B is a BB direction view of FIG. 3 (c) is a view in the direction of the arrow CC in FIG. 3 (a).

  In FIGS. 3A, 3B, and 3C, the same components as those shown in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The heat storage system of this application example further includes solid-phase stripping means 19 for stripping off the solid-phase heat storage material 2 adhering to the surface of the heat radiating heat transfer tubes 4a, 4b, 4c in the same configuration as the first embodiment. It is set as the structure provided.

  The solid-phase stripping means 19 is supplied from the outside with individual nitrogen blowing pipes 20a, 20b, and 20c respectively arranged at positions below the heat-radiating heat transfer pipes 4a, 4b, and 4c in the internal space of the heat storage tank 1. A compressor 21 for compressing nitrogen, a branched nitrogen supply line 22 connecting the nitrogen delivery side of the compressor 21 and the nitrogen blowing pipes 20a, 20b, 20c, and a nitrogen blowing pipe 20a at each branch portion of the nitrogen supply line 22. , 20b, 20c are provided with on-off valves 23a, 23b, 23c provided individually. The on-off valves 23a, 23b, 23c are connected to a controller (not shown), and the opening / closing operation is individually controlled.

  For example, as shown in FIGS. 3A and 3C, the nitrogen blowing pipes 20 a, 20 b, and 20 c include a blower outlet 24 that blows out bubbles 25 in the vicinity of the side wall 1 a of the heat storage tank 1. Thereby, when the bubble 25 is blown out from the blowout port 24 of the nitrogen blowing pipes 20a, 20b, and 20c, the liquid phase of the heat storage material 2 above the nitrogen blowing pipes 20a, 20b, and 20c is outlined in FIG. As shown by the arrow, a flow that rises with the rising of the bubbles 25 near the side wall 1a of the heat storage tank 1 and then descends near the center of the heat storage tank 1 occurs. Therefore, by applying the liquid phase flow of the heat storage material 2 to the heat-dissipating heat transfer tubes 4a, 4b, 4c, the solid-state heat storage material 2 adhering to the surface of the heat-dissipating heat transfer tubes 4a, 4b, 4c is promoted. be able to.

  Furthermore, the solid phase peeling means 19 is located above the nitrogen blowing tubes 20a, 20b, 20c in the internal space of the heat storage tank 1 and at a position between the adjacent heat transfer tubes 4a, 4b, 4c for heat radiation. It is preferable to provide the partition plate 26 and partition the regions where the heat transfer tubes 4a, 4b, 4c for heat radiation are arranged. According to the configuration including the partition plate 26, the liquid phase flow of the heat storage material 2 generated above each of the nitrogen blowing tubes 20 a, 20 b, and 20 c causes the heat transfer tubes 4 a, 4 b, and 4 c for heat radiation to flow through the partition plate 26. The spread in the arranged horizontal direction is suppressed. Therefore, the flow of the liquid phase of the heat storage material 2 generated when the bubbles 25 are blown out from the nitrogen blowing pipes 20a, 20b, and 20c is efficiently performed by the heat-dissipating heat transfer pipes 4a, 4b, and 4c located above each of the heat blowing materials. It is possible to further promote the peeling of the solid-state heat storage material 2 from the surfaces of the heat transfer tubes 4a, 4b, 4c for heat radiation.

  When performing heat dissipation processing using the heat storage system of this application example, the temperature measurement value of the heat-dissipating heat medium 5 recovered from the heat storage tank 1 is controlled by the temperature measuring device 11 as in the first embodiment. 12 is input. The control device 12 gives commands to the valves 7a, 7b, 7c according to the temperature measurement values, and appropriately controls the number of heat radiating heat transfer tubes 4a, 4b, 4c through which the heat radiating heat medium 5 flows.

  Further, in this application example, when the number of the heat radiating heat transfer tubes 4a, 4b, 4c through which the heat radiating heat medium 5 is circulated is controlled by the control device 12 as described above, the on / off valves 23a, 23b are controlled by a controller (not shown). , 23c is opened and closed so that nitrogen is supplied from the compressor 21 through the nitrogen supply line 22 only to the nitrogen blowing pipes located below the heat radiating heat transfer pipes 4a, 4b, 4c through which the heat radiating heat medium 5 flows. To do.

  Thereby, about the heat-radiation heat exchanger tubes 4a, 4b, and 4c in which the heat-radiating heat medium 5 flows and the solid phase of the heat storage material 2 is generated on the surface, the bubbles 25 are blown out by the nitrogen blowing tubes 20a, 20b, and 20c. The flow of the liquid phase of the heat storage material 2 to be generated can be applied to promote the peeling of the solid phase heat storage material 2.

  At this time, the nitrogen blowing pipes 20a, 20b, and 20c to which nitrogen is supplied are only located below the heat radiating heat transfer pipes 4a, 4b, and 4c through which the heat radiating heat medium 5 circulates. The energy required for the operation of 19 can be reduced as compared with the case where the liquid phase flow of the heat storage material 2 is generated in the entire internal space of the heat storage tank 1.

  More preferably, the solid phase stripping means 19 intermittently increases the amount of bubbles 25 generated and efficiently strips the solid phase heat storage material 2 from the heat transfer tubes 4a, 4b, 4c. Moreover, although the case where the bubble 25 was blown out and the bubble 25 was generated was demonstrated, you may use inert gas, such as not only nitrogen but argon.

  Further, the solid phase peeling means 19 is not limited to this. For example, although not shown, the liquid phase of the heat storage material 2 in the heat storage tank 1 is sucked and the liquid phase of the sucked heat storage material 2 is stored in the heat storage tank. 1 is provided with a circulation pump that discharges the inside of the heat storage material 2, and the liquid phase of the heat storage material 2 discharged from the circulation pump causes a flow similar to that indicated by the white arrow in FIG. You may make it form. The same effect as described above can also be obtained by the solid phase peeling means 19 having this configuration.

[Second Application Example of First Embodiment]
FIG. 4 is a schematic diagram showing a second application example of the first embodiment.

  In FIG. 4, the same components as those shown in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In the heat storage system of this application example, the heat load X having the same configuration as that of the first embodiment is a heat exchanger X1 that performs heat exchange between the heat dissipation heat medium 5 and another heat medium 27.

That is, as described in the first embodiment, the heat dissipation heat medium 5 stays in the heat dissipation heat transfer tubes 4a, 4b, 4c when the valves 7a, 7b, 7c are closed. Considering this, a material having a stable property is used even at the maximum heat storage temperature T _max set in the heat storage tank 1.

Therefore, for example, when the maximum heat storage temperature T _max is 400 ° C., the temperature is almost the upper limit temperature of the temperature range that can be used in a widely used oil-based heat medium. Therefore, in this case, it is necessary to use, for example, a molten salt as a heat medium that can be used at a higher temperature, instead of a general oil-based heat medium, as the heat dissipation heat medium 5.

  On the other hand, for equipment on the heat utilization side, it may be desired to supply a general oil-based heat medium. That is, since the molten salt is generally solidified at about 100 ° C., if there is a risk that the temperature of a part of the device on the heat utilization side is lowered to about 100 ° C., the molten salt as a heat medium is solidified in the device. On the other hand, the oil-based heat medium is less likely to solidify even at about 100 ° C. and can be stably operated.

  Therefore, in this application example, the heat exchanger X1 performs heat exchange between the two fluids of the first fluid and the second fluid, and the downstream side of the heat dissipation heat medium delivery line 10 is connected to the heat exchanger X1. The first fluid inlet 28 is connected.

  The first fluid outlet 29 of the heat exchanger X1 is connected, for example, to the upstream side of the heat dissipation heat medium supply line 8 via a circulation pump 30. Therefore, in this application example, the heat-dissipating heat medium supply means for the heat storage tank 1 is the heat exchanger X1 and the circulation pump 30.

  The second fluid inlet 31 of the heat exchanger X1 is connected to, for example, a supply means (not shown) of a heat medium 27 as an oil system via a heat medium supply line 32, and the second fluid outlet 33 is supplied with a heat medium delivery. A heat utilization side device (not shown) is connected via a line 34.

  According to the heat storage system of this application example having the above-described configuration, the heat radiation processing from the heat storage tank 1 to the heat dissipation heat medium 5 and the heat storage heat treatment to the heat storage tank 1 can be performed in the same manner as in the first embodiment. Thus, the same effect as in the first embodiment can be obtained.

Furthermore, according to this application example, the heat dissipation heat medium 5 heated by heat dissipation from the heat storage tank 1 is sent to the heat exchanger X1 and used as a heat source for heating the heat medium 27. Although the heat medium 27 is heated by this heat exchange, the temperature reached is lower than that of the heat dissipation heat medium 5 supplied to the heat exchanger X1. Therefore, since the heat medium 27 does not reach a high temperature such as the maximum heat storage temperature T _max of the heat storage tank 1, a general oil-based heat medium can be used as the heat medium 27.

  Accordingly, heat radiated from the heat storage material 2 of the heat storage tank 1 is transferred to the heat utilization side device downstream of the second fluid outlet 33 of the heat exchanger X1 from the heat dissipation heat medium 5 and the oil-based heat medium 27. And can be given indirectly through. Moreover, the demand for supplying a general oil-based heat medium 27 can also be satisfied for the equipment on the heat utilization side.

[Third application example of the first embodiment]
FIG. 5 is a schematic diagram showing a third application example of the first embodiment.

  In FIG. 5, the same components as those shown in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  The heat storage system of this application example has the same configuration as that of the first embodiment, and means for obtaining the temperature of the heat dissipating heat medium 5 collected after flowing through the heat dissipating heat transfer tubes 4a, 4b, 4c is a heat dissipating heat medium. In place of the configuration of the temperature measuring device 11 that directly measures the temperature 5, the temperature measuring device 35 that measures the temperature of the heat storage material 2 and the heat dissipation heat medium that is recovered based on the input from the temperature measuring device 35 And a calculator 36 for calculating the temperature of 5.

  By the way, if the initial temperature of the heat-dissipating heat medium 5 supplied from the heat-dissipating heat medium supplying means (not shown) is constant, the heat storage material 2 and the heat-dissipating heat medium 5 depend on the temperature of the heat storage material 2. The temperature difference is determined. Further, if the heat transfer area between the heat storage material 2 and the heat dissipation heat medium 5 is constant, the heat storage material 2 and the heat dissipation heat medium depend on the temperature difference between the heat storage material 2 and the heat dissipation heat medium 5. The heat release rate to 5 is determined. If this heat dissipation rate is determined, the temperature of the heat dissipation heat medium 5 recovered after flowing through the heat transfer tubes 4a, 4b, 4c for heat dissipation can be calculated.

  In addition, the heat transfer area between the heat storage material 2 and the heat dissipation heat medium 5 at a certain time is the heat transfer area per heat transfer tube 4a, 4b, 4c for heat dissipation, and the heat transfer heat medium 5 is circulated at that time. It can be obtained by multiplying the number of the heat transfer tubes 4a, 4b, 4c for radiation.

  Therefore, based on the information on the initial temperature of the heat-dissipating heat medium 5, the temperature of the heat storage material 2, and the number of heat-dissipating heat transfer tubes 4a, 4b, 4c through which the heat-dissipating heat medium 5 is distributed, The temperature of the heat-dissipating heat medium 5 collected after passing through 4a, 4b, 4c can be calculated.

  Therefore, an arithmetic expression for performing the above calculation is input to the calculator 36.

  Further, the initial temperature of the heat radiating heat medium 5 is also input to the calculator 36. In addition, when the fluctuation | variation of initial temperature is assumed about the thermal medium 5 for thermal radiation, the initial temperature of the thermal medium 5 for thermal radiation is shown, for example from the temperature measuring device which is not shown in the thermal medium supply line 8 or the distribution pipe 6 for thermal radiation. You may make it input the measured value of.

  Further, the calculator 36 receives the number of the valves 7a, 7b, 7c in the open operation state from the control device 12, that is, the heat transfer heat transfer tubes 4a, 4b, 4c through which the heat transfer heat medium 5 is circulated. Number information is entered.

  Therefore, when the temperature measurement value of the heat storage material 2 is input from the temperature measuring device 35, the computing unit 36 distributes the temperature measurement value, the initial temperature of the heat dissipation heat medium 5, and the heat dissipation heat medium 5. Based on the information on the number of heat transfer tubes 4a, 4b, and 4c for heat dissipation, the temperature of the heat dissipating heat medium 5 collected after flowing through the heat transfer tubes 4a, 4b, and 4c for heat dissipation is calculated. Thereafter, the calculation result is sent from the computing unit 36 to the control device 12.

  Therefore, also in this application example, the control device 12 is based on the calculation result of the temperature of the heat-dissipating heat medium 5 collected after flowing through the heat-dissipating heat transfer tubes 4a, 4b, 4c input from the calculator 36. The heat dissipation process similar to 1st Embodiment can be performed.

  Therefore, the heat storage system of this application example can be used in the same manner as in the first embodiment to obtain the same effect.

  In addition, the heat storage system of each said embodiment is as a solid-phase peeling means for mechanically peeling off the solid-phase heat storage material 2 adhering to the surface of the heat transfer tubes 4a, 4b, 4c for heat radiation in the heat storage tank 1. It is good also as a structure provided with the same mechanical solid-phase exfoliation means as was shown by patent document 1. FIG. The solid phase stripping means includes, for example, a slide plate having a heat transfer tube insertion hole through which the heat transfer tubes 4a, 4b, and 4c for heat radiation are formed, a slide member having a tapered tip, and a slide member having a bearing at the tip. The actuator is made to reciprocate along the surfaces of the heat radiating heat transfer tubes 4a, 4b, 4c and mechanically peel off the solid state heat storage material 2 from the surface of the heat radiating heat transfer tubes 4a, 4b, 4c. , Etc. may be adopted. In this case, it is preferable to provide solid-state stripping means that reciprocates individually for each of the heat transfer tubes 4a, 4b, 4c for heat radiation.

  Further, the present invention is not limited to the first embodiment and each application example, but the vertical size and diameter size of the heat storage tank 1 shown in each drawing, the thickness of the heat transfer tubes 4a, 4b, 4c for heat radiation. The dimensions of other parts are for convenience of illustration and do not reflect actual dimensions.

  The first application example, the second application example, and the third application example may have a plurality of configurations in arbitrary combinations.

  Although the heat storage tank 1 showed the structure arrange | positioned so that the heat exchanger tube 4a, 4b, 4c for heat radiation may penetrate a side wall, you may set the piping path | route of the heat exchanger tubes 4a, 4b, 4c for heat radiation arbitrarily. . Also, the piping paths of the heat transfer tubes 4a, 4b, 4c near the upper portion of the internal space of the heat storage tank 1 may be any piping paths other than those illustrated depending on the size and shape of the internal space.

  The valves 7a, 7b, and 7c may be any type of valve such as an on-off valve and a flow rate control valve as long as the heat dissipation heat medium 5 can be supplied to and stopped from the heat transfer tubes 4a, 4b, and 4c. May be used.

  The configuration in which one heat-dissipating heat transfer tube 4a, 4b, 4c is connected to the downstream side of the valves 7a, 7b, 7c is shown, but a plurality of heat-dissipating heat transfer tubes are connected to the valves 7a, 7b, 7c. It is good also as a structure.

  Further, the number of heat transfer tubes for heat radiation provided in the heat storage tank 1 may be two, or four or more, depending on the size of the heat storage tank 1 or the like. In addition, the heat transfer area of the heat storage material 2 and the heat-dissipating heat medium 5 increases or decreases as the number of heat-dissipating heat transfer tubes that can be individually switched between supply and stop of the heat-dissipating heat medium 5 by the valve. This is preferable in that the stepwise change width is small.

  Further, when the number of heat-dissipating heat transfer tubes 4a, 4b, 4c through which the heat-dissipating heat medium 5 is circulated is switched, the heat-dissipating heat medium 5 sent to the heat exchanger X1 as the heat load X or the heat load is suddenly changed. From the viewpoint of relaxing the temperature change, it is preferable to increase the volume of the collecting pipe 9.

  Although the heat transfer tubes 4a, 4b, 4c for heat radiation have been shown to be arranged in the heat storage tank 1 in the horizontal direction, as shown in FIGS. .

  The heating means 3 of the heat storage tank 1 has a configuration in which the heating medium supply line 16 and the heating medium return line 17 are connected to the heating medium channel 14 from the outside. Either or both of the heat medium return lines 17 may be arranged through the heat storage tank 1.

  As the heat storage material 2, it is preferable to use a material composed of the two-component mixed salt of the exemplified non-eutectic composition. However, a solid-liquid phase change occurs in the heat storage temperature range of the heat storage tank 1, and If the density is larger than the density of the liquid phase, a single component salt (molten salt), a mixed salt of three or more components of a non-eutectic composition, a mixed salt of a plurality of components of a eutectic composition, other than salts Any heat storage material may be used.

  The heat storage temperature range may be freely changed according to the heat source, the heat load X, the type of heat utilization device connected to the heat exchanger X1, and the like. Similarly, the temperature desired for the heat-dissipating heat medium 5 sent to the heat load X or the heat exchanger X1 (sending heat medium temperature T0) may be freely changed.

  The heat storage tank 1 preferably includes a heat storage material 2 that causes a solid-liquid phase change in a heat storage temperature range, but may include a heat storage material that does not cause a phase change.

  Of course, various modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Heat storage tank, 2 Thermal storage material, 3 Heating means, 4a, 4b, 4c Heat-radiation heat transfer tube, 5 Heat-radiation heat medium, 7a, 7b, 7c Valve, 11 Temperature measuring device (Means for calculating | requiring the temperature of the heat-radiation heat medium) , 12 Control device, 19 Solid phase peeling means, 35 Temperature measuring device (means for obtaining the temperature of the heat dissipation heat medium), 36 Calculator (means for obtaining the temperature of the heat dissipation heat medium)

Claims (4)

A heat storage tank,
A heat storage material placed in the heat storage tank;
In the tank of the heat storage tank, a plurality of heat dissipation heat transfer tubes that circulate a heat-dissipating heat medium lower in temperature than the heat storage material and exchange heat with the heat storage material,
A plurality of valves for switching between supply and supply stop of the heat dissipation heat medium to the plurality of heat dissipation heat transfer tubes;
A heating means provided in the heat storage tank for heating the heat storage material for heat storage;
Means for determining the temperature of the heat-dissipating heat medium recovered after circulating the heat-dissipating heat transfer tube;
A heat storage system comprising: a control device that gives an individual control command to the valve based on an input from the means. The heat storage material shall produce a solid-liquid phase change in the heat storage temperature range of the heat storage tank,
2. The heat storage system according to claim 1, wherein the heat storage tank includes the heat-dissipating heat transfer tube near an upper portion of the internal space containing the heat storage material, and includes the heating unit on a bottom side of the internal space. The heat storage system according to claim 2, wherein the heat transfer tubes for heat radiation, which are switched between supply and stop of the heat dissipation heat medium by the valves, are arranged in the horizontal direction in the internal space of the heat storage tank. . 4. The heat storage system according to claim 3, wherein each heat radiation heat transfer tube, which is switched between supply and stop of supply of the heat radiation heat medium by the valves, individually includes solid phase peeling means.

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