JP5749999B2 - Heat storage device - Google Patents

Description

  The present invention relates to a heat storage device that heats a heat storage body by exhaust heat from a heat source.

  Conventionally, a cogeneration system has been developed that uses exhaust heat from an internal combustion engine or an external combustion engine to extract power, heat, and cold to increase overall energy efficiency. This cogeneration system includes, for example, a cogeneration device composed of a heat engine such as an engine or a gas turbine and a generator, and burns fuel in the heat engine to drive the generator to generate power. The system is configured to perform heating and hot water supply using exhaust heat, and in recent years, a system using a fuel cell as a cogeneration device has been proposed.

  In order to effectively use the exhaust heat from the heat engine or the fuel cell, it is necessary to store the heat. As a heat storage material for storing heat, water is generally used because it has a high specific heat, is safe and inexpensive, but when water is used as a heat storage material, it stores heat with its sensible heat. Therefore, the heat capacity per unit volume is not sufficient, and there is a problem that the heat storage container becomes large in order to store a lot of heat.

  In order to solve this problem, a method of storing heat using a latent heat storage material has been proposed. Since the latent heat storage material has a larger heat capacity per unit volume than water, the apparatus can be downsized.

  For example, in patent document 1, the hot water storage tank and the heat storage tank which accommodated the latent heat storage material are used together, and thereby, the heat storage device is downsized without changing the amount of heat that can be stored in the entire heat storage device.

  Moreover, in patent document 2, each is equipped with the thermal storage material tank which accommodated the latent heat storage material and water as a thermal storage material, and since the hot water storage tank is not provided, it is possible to comprise an apparatus small.

JP 2010-186668 A JP 2007-205618 A

  However, in the conventional heat storage device, the heat storage tank and the hot water storage tank, or the heat storage material tanks are connected by piping, so that not only the structure is complicated, but also heat is released from this piping, so the heat storage efficiency is lowered. There is a risk that. And since many valves which control piping are also used, an apparatus will be further complicated.

  Further, since the hot water storage tank is not provided in the configuration of Patent Document 2, the apparatus can be reduced in size, but instead, a heat exchanger is also required on the hot water supply side.

  This invention is for solving the said subject, and it aims at providing a heat storage apparatus with high heat storage capability while simplifying a structure and enabling size reduction.

The present invention includes a sensible heat storage unit, a latent heat storage unit provided in close contact with an outer periphery of the sensible heat storage unit, a heating path for heating the sensible heat storage unit by exhaust heat from a heat source, and the sensible heat A cooling path for cooling the heat storage unit, a case provided via an air passage between the latent heat storage unit, a communication port for communicating the air passage and the outside of the heat storage device, and opening / closing for opening and closing the communication port The opening and closing member is a heat storage device that opens a communication port when the amount of heat stored in the latent heat storage unit reaches a predetermined value .

By configuring as described above, the configuration is simple because complicated piping is not required, and heat is efficiently transferred from the sensible heat storage unit to the latent heat storage unit, so heat loss is reduced and heat storage efficiency is improved. Can be raised. Moreover, while the case provided in the outer periphery of the latent heat storage part suppresses heat radiation to the outside, it is possible to forcibly radiate heat by opening the communication port.

It is the schematic of the cogeneration system using the heat storage apparatus of this invention. It is a top-sectional view of the heat storage unit of the present invention. It is sectional drawing of the thermal storage apparatus of this invention.

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode of the present invention, which is considered preferable, will be briefly described by showing the effects of the present invention.

  The heat storage device of the present invention uses a sensible heat storage material and a latent heat storage material as the heat storage material, and closely contacts a latent heat storage portion containing the latent heat storage material on the outer periphery of the sensible heat storage portion containing the sensible heat storage material. In addition, a path for heating and cooling the heat storage material is disposed in the sensible heat storage section.

  In other words, since the piping connecting the sensible heat storage part and the latent heat storage part becomes unnecessary, the apparatus can be simplified, and when transferring heat between the sensible heat storage part and the latent heat storage part Heat loss is eliminated and heat storage efficiency can be increased.

  And since the path | route which heats and cools a thermal storage material is provided in the sensible heat storage part with high heat conductivity, since a heating and cooling path | route can perform heat exchange with a thermal storage material quickly, Heating and cooling can be performed efficiently.

In addition, since the outer periphery of the latent heat storage unit is surrounded by a case having heat insulation performance through an air passage, when heat is stored in the heat storage material, heat dissipation to the outside of the heat storage device can be suppressed by the case and the air passage. it can. On the other hand, since the air passage has a communication port communicating with the outside of the apparatus, forcibly latent heat by aeration is carried out to open the communication port when the heat amount accumulated in the heat storage material has exceeded a predetermined amount It is also possible to dissipate heat from the heat storage unit.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic view of a cogeneration system using the heat storage device of the present invention. The heat storage device 1 includes a heat storage unit 2 that stores heat, a heating path 3 that heats the heat storage unit 2, and a cooling path 4 that takes heat from the heat storage unit 2 and cools it.

  The heating path 3 is provided with a circulation pump 5, which performs heat exchange with exhaust heat generated from the power generation unit 20 that is a heat source via the heat exchanger 21, and heats the heat storage unit 2 with the heat. ing.

  Since the power generation unit 20 generates heat along with power generation, it will interfere with power generation unless it is cooled. However, the power generation unit 20 is cooled by exchanging heat with the heating path 3 in the heat exchanger 21, so power generation is continued. It can be carried out. The power generation unit 20 may be any unit that generates heat during power generation, such as an engine, a gas turbine, or a fuel cell, and the type of the power generation unit 20 is not particularly limited.

  One end of the cooling path 4 is a fluid supply port 6 for supplying a fluid for recovering heat from the heat storage unit 2 such as water or air into the cooling path 4. Is provided with an electrical component 7 for delivering fluid. Specifically, the electrical component 7 is provided with a pump when the fluid is water and a blower when the fluid is air. And the other end serves as a fluid discharge port 8 for discharging the fluid heated by passing through the heat storage unit 2, and hot water and hot air are discharged.

  FIG. 2 is a plan-sectional view of a heat storage unit constituting the heat storage device of the present invention. The heat storage unit 2 includes a sensible heat storage unit 9 containing a sensible heat storage body at the center, and the outer periphery of the sensible heat storage unit 9. The latent heat storage part 10 which accommodated the latent heat storage body is arrange | positioned. The substantially U-shaped heating path 3 and cooling path 4 are arranged inside the sensible heat storage unit 9 without crossing each other.

  The heating path 3 has a shape in which a large number of heat transfer fins 11a for expanding the heat radiation area are provided in a cylindrical pipe member, and an antifreeze liquid circulates in the heat path 3 from the power generation unit 20. Heat is raised by exchanging heat with exhaust heat, and heat is released.

  The sensible heat storage body constituting the sensible heat storage unit 9 uses a liquid having a relatively high thermal conductivity, such as water or antifreeze, and a low heat capacity, and the heat released from the heating path 3 through the heat transfer fins 11a. Can be absorbed quickly to raise the temperature.

  On the other hand, for example, sodium acetate hydrate is used as the latent heat storage body constituting the latent heat storage unit 10. When the latent heat storage body is melted by the application of heat, the amount of heat applied at this time becomes latent heat. Heat is stored in the latent heat storage unit 10. Although the latent heat storage body has a lower thermal conductivity than the sensible heat storage body but has a large heat capacity, the stored heat can be released for a long time.

  A heat transfer member 12 is provided inside the latent heat storage unit 10, and the heat released from the sensible heat storage unit 9 that has been heated is transferred to the latent heat storage body via the heat transfer member 12, thereby latent heat storage. The heating efficiency of the part 10 is improved.

  Further, the sensible heat storage unit 9 and the latent heat storage unit 10 are provided in close contact with each other so that heat loss does not occur when heat is transmitted.

  The cooling path 4 has a shape in which a large number of heat transfer fins 11 b are provided in a cylindrical pipe member, as in the heating path 3, and a fluid is introduced into the pipe member from the fluid supply port 6 by the operation of the electrical component 7. The sensible heat storage unit 9 is deprived of heat by this fluid and the sensible heat storage unit 9 is cooled. The fluid heated by taking heat from the sensible heat storage unit 9 is discharged from the fluid discharge port 8.

  3 is a cross-sectional view of the heat storage device, and a case 13 made of a heat insulating material is provided so as to surround the heat storage unit 2, and an air passage 14 through which air passes is provided between the latent heat storage unit 10 and the case 13. Is formed. In addition, communication ports 15a and 15b through which the air passage 14 communicates with the outside of the heat storage device 1 are provided at predetermined positions of the case 13, and an opening / closing member 16 that opens and closes the communication ports 15a and 15b is provided. The operation of the opening / closing member 16 is controlled by the amount of heat stored in the latent heat storage unit 10.

  Heat transfer fins 11 c are formed on the outer periphery of the latent heat storage unit 10, and air flowing from the communication port 15 a exchanges heat with the heat transfer fins 11 c while passing through the air passage 14, thereby generating heat from the latent heat storage unit 10. And is discharged from the other communication port 15b.

  Next, operation | movement of the thermal storage apparatus 1 which consists of the structure mentioned above is demonstrated. The heat storage device 1 of the present invention has a heat storage operation for storing heat in the heat storage unit 2, a cooling operation for recovering the heat of the heat storage unit 2 through a cooling path, and a heat dissipation operation for forcibly radiating the heat of the heat storage unit 2. Three operations are performed, and a case where water is used as an example of a fluid for recovering heat through the cooling path 4 will be described below.

  Thermal storage operation: When the power generation unit 20 serving as a heat source performs a power generation operation, heat is discharged along with this, so that the antifreeze circulating in the heating path 3 exchanges heat with the exhaust heat by the heat exchanger 21. As the temperature rises, heat is released from the heating path 3. In the heat storage unit 2, since the sensible heat storage unit 9 is disposed in close contact with the heating path 3, the heat released from the heating path 3 is absorbed by the sensible heat storage unit 9. Since the sensible heat storage material has high thermal conductivity, the temperature rises quickly upon receiving heat.

  On the other hand, the antifreeze circulating in the heating path 3 is deprived of heat by exchanging heat with the sensible heat storage unit 9, and the temperature is lowered when leaving the heat storage unit 2. Therefore, when the antifreeze liquid having a low temperature flows into the heat exchanger 21, the power generation unit 20 is cooled and power generation can be continued.

  The heat stored in the sensible heat storage unit 9 is further supplied to the latent heat storage unit 10 on the outer periphery thereof. Since the latent heat storage unit 10 is disposed in close contact with the sensible heat storage unit 9, all the heat released from the sensible heat storage unit 9 is absorbed by the latent heat storage unit 10. Further, since the heat transfer member 12 provided inside the latent heat storage unit 10 transfers the heat released from the sensible heat storage unit 9 from the inside of the latent heat storage unit 10, the latent heat storage unit 10 has a boundary with the sensible heat storage unit 9. It is heated not only from the surface but also from the inside, and the heating efficiency is improved.

  When the temperature of the latent heat storage body reaches the melting temperature, the latent heat storage body is melted and this latent heat is stored in the latent heat storage section 10.

  Since the opening / closing member 16 of the case 13 is closed at this time, the heat stored in the latent heat storage unit 10 is suppressed from being released to the outside by the air passage 14 and the case 13, so the heat storage unit 2 maintains a high temperature. It becomes possible.

  Cooling operation: When there is a request for hot water supply while heat is stored in the heat storage unit 2, the pump 7, which is an electrical component, operates and water is introduced into the cooling path 4 from the fluid supply port 6. The water introduced into the path 4 becomes hot water by removing heat from the sensible heat storage unit 9 while passing through the heat storage unit 2, and is discharged from the fluid discharge port 8. That is, in this heat storage device, a hot water storage tank is not required for hot water supply, and further heat exchange is performed in the heat storage unit 2, so that the configuration is simplified and the device can be miniaturized.

  Since the sensible heat storage unit 9 is cooled by water passing through the cooling path 4, the temperature is lowered, but the sensible heat storage unit 9 is heated to a constant temperature by being heated by the heat released by the latent heat storage unit 10 provided on the outer periphery. Can keep.

  The heat storage operation may be performed simultaneously with the cooling operation. In this case, the sensible heat storage unit 9 is cooled by the cooling path 4 and simultaneously heated by the heating path 3.

  Similarly to the heat storage operation, the opening / closing member 16 of the case 13 is closed during the cooling operation, so that the heat stored in the latent heat storage unit 10 is suppressed from being released to the outside by the air passage 14 and the case 13. It is done.

  The heat storage unit 2 is heated by performing the heat storage operation in this manner, and the heat storage unit 2 is cooled by performing the cooling operation. When the heat storage operation and the cooling operation are balanced, heat can be stored in the heat storage unit 2 by the heat storage operation as much as the heat storage unit 2 is cooled by the cooling operation, so the antifreeze circulating in the heating path 3 is sensible heat After the heat storage unit 9 is deprived of heat and passes through the heat storage unit 2, the temperature is lowered. Therefore, the heating path 3 can cool the power generation unit 20 via the heat exchanger 21.

  However, the amount of heat usually taken away by the cooling operation and the amount of heat stored by the heat storage operation are not the same, and it is expected that the amount of heat stored by the heat storage operation will increase. When the amount of heat stored in the latent heat storage unit 10 reaches a predetermined amount, the sensible heat storage unit 9 cannot take heat from the heating path 3, so the antifreeze liquid in the heating path 3 after passing through the heat storage unit 2 is hot. Is maintained. Then, since the antifreeze liquid flows into the heat exchanger 21 with the temperature being high, the power generation unit 20 cannot be cooled, the power generation operation is hindered, and the power generation operation must be regulated. Therefore, in order to avoid such a state, when the heat storage amount reaches a predetermined value, a heat radiation operation for forcibly radiating the latent heat storage unit 10 is performed.

  Heat release operation: When it is determined that the amount of heat stored in the latent heat storage unit 10 exceeds a predetermined amount, the opening / closing member 16 of the case 13 is opened, and air is caused to flow into the heat storage device from the communication port 15a. Then, the air flowing in from the communication port 15 a receives the heat released from the latent heat storage unit 10 while passing through the air passage 14, rises in temperature, and is discharged from the other communication port 15 b. Thereby, the latent heat storage unit 10 is cooled and the temperature is lowered, so that the sensible heat storage unit 9 can take heat from the heating path 3.

  When it is determined that the amount of heat stored in the latent heat storage unit 10 has become equal to or less than a predetermined amount by continuing the heat dissipation operation, the open / close member 16 is closed to block subsequent heat dissipation.

  The case 13 plays a role of suppressing the release of heat from the latent heat storage unit 10 to the outside during the heat storage operation and the cooling operation and maintaining it at a high temperature. However, during the heat dissipation operation, the latent heat storage is performed by opening the opening / closing member 16. The portion 10 can be cooled by dissipating heat. That is, since it is not necessary to separately provide a cooling device such as a radiator for cooling the latent heat storage unit 10, it is possible to make the device more compact and inexpensive.

DESCRIPTION OF SYMBOLS 3 Heating path 4 Cooling path 6 Fluid supply port 8 Fluid discharge port 9 Sensible heat storage part 10 Latent heat storage part 13 Case 14 Air passage 15a, 15b Communication port 16 Opening / closing member

Claims (1)

A sensible heat storage unit, a latent heat storage unit provided in close contact with the outer periphery of the sensible heat storage unit, a heating path for heating the sensible heat storage unit by exhaust heat from a heat source, and cooling the sensible heat storage unit A cooling path that is connected to the latent heat storage unit through an air passage, a communication port that connects the air passage to the outside of the heat storage device, and an opening and closing member that opens and closes the communication port. The opening / closing member opens the communication port when the amount of heat stored in the latent heat storage unit reaches a predetermined value .

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