JP2014181864A - Heat storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat storage device capable of exhibiting high heat storage performance even in an environment where temperature changes throughout the year.
A heat storage device 1 according to the present invention includes a crushed stone 6 for collecting underground heat, a heat storage tank 3 for storing heat collected by the crushed stone 6, and a heat medium for moving the heat storage of the heat storage tank 3. And a heat exchanger 5 in which heat exchange between the heat medium and the refrigerant in the refrigerant pipe 14 of the air conditioner 13 is performed, and the heat storage tank 3 has a normal melting point of 12 ° C. Paraffin 15 and normal paraffin 16 having an average melting point of 18 ° C. are included.
[Selection] Figure 1

Description

  The present invention relates to a heat storage device using a latent heat storage material.

  Geothermal heat is low-temperature thermal energy existing in shallow ground within 200m underground. In general, the depth below 5 m underground is maintained at a constant temperature throughout the year, and is said to be about 10 ° C in Hokkaido, about 17 ° C in Tokyo, and about 20 ° C in the southern part of Kyushu.

  This approach of using constant heat has been conducted for a long time, and basement, underground storage, cooling of well water, etc. were typical forms of use of geothermal heat. In recent years, buried pipes have been buried from the ground surface to a depth of 100 m or deeper, and the heat medium in the buried pipes absorbs or dissipates heat in the ground, and heat is exchanged by a heat exchanger installed near the ground surface. There are many efforts to use the as a heat source in winter and as a cold source in summer.

  On the other hand, since there is a problem that the installation of the buried pipe is expensive, for example, Patent Document 1 describes an air conditioning system that guides underground heat to a foundation concrete board of a building and uses it for air conditioning. .

Japanese Patent Laid-Open No. 2007-127397

  However, in the air conditioning system described in patent document 1, since heat is stored in the foundation concrete board of a building, heat capacity is not necessarily large. Therefore, it is conceivable to increase the heat capacity using a heat storage material. However, in an environment where the temperature changes throughout the year as in Japan, the ambient temperature of the heat storage material also increases or decreases throughout the year. In the process, latent heat is stored only for a short period in which the ambient temperature crosses the melting point of the heat storage material, and it is difficult for the heat storage amount in summer (or winter) to meet the demand in winter (or summer).

  This invention is made | formed in view of said situation, and makes it a subject to provide the thermal storage apparatus which can exhibit high thermal storage performance also in the environment with a temperature change through the year.

  In order to solve the above-mentioned problem, the invention according to claim 1 is directed to heat storage means for storing heat collected by heat collecting means for collecting heat of the ground or outside air or solar heat, and moving heat storage of the heat storage means. A heat storage device including a flow path through which the heat medium flows and heat exchange means for performing heat exchange between the heat medium and an external device, wherein the heat storage means includes a plurality of latent heat storage materials having different melting points. And

  According to a second aspect of the present invention, in the heat storage device according to the first aspect, the heat collecting means collects heat in the ground, and at least one of the plurality of latent heat heat storage materials is higher than the temperature in the ground. The melting point is high, and the other one of the plurality of latent heat storage materials has a melting point lower than the underground temperature.

  The invention according to claim 3 is the heat storage device according to claim 2, characterized in that the heat storage means is provided inside a thin underground layer or the foundation of a building.

  The invention according to claim 4 is the heat storage device according to any one of claims 1 to 3, wherein at least one of the plurality of latent heat storage materials is water, normal paraffin, stearic acid, sodium acetate hydrate, thio Sodium sulfate hydrate, sodium carbonate decahydrate, dibasic sodium phosphate, calcium chloride, quaternary ammonium salt hydrate, fatty acid triglyceride, alkylene oxide polymer, decaglycerin-lauric acid reactant, decaglycerin-myristic acid It contains a reactant, decaglycerin-palmitic acid reactant, decaglycerin-stearic acid reactant, decaglycerin-behenic acid reactant, erythritol or xylitol.

  According to a fifth aspect of the present invention, in the heat storage device according to any one of the first to fourth aspects, at least one of the plurality of latent heat storage materials is liquid, solid, or gel.

  The invention according to claim 6 is the heat storage device according to any one of claims 1 to 5, wherein at least one of the plurality of latent heat storage materials is included in a capsule.

  Here, “heat collection” means not only heat absorption but also heat radiation, and “stores heat” means not only warm heat but also cold heat.

  The “underground temperature” means a substantially constant temperature in the ground where the heat collecting means collects heat, and is generally a temperature of 5 m or deep underground that is stable throughout the year (for example, several tens of meters below the ground). In places where there are structures, the temperature at deeper points can be set as the “underground temperature”, and even if the temperature is at a point shallower than 5 m underground, the ground surface is covered with buildings, etc. If it is stable and not easily affected by the sun or the outside air, it is included in the “Ground temperature”.)

  Furthermore, “the heat storage means is provided in the underground thin layer” or “provided” means that at least a part of the heat storage means is an underground thin layer (subsurface temperature is substantially constant and is approximately 100 m underground). "The heat storage means" is "provided inside the foundation of the building" means that at least a part of the heat storage means is a rising part of the foundation in a side view. Means that it is surrounded by the rising part etc. in plan view (an aspect in which at least a part of the heat storage means can be evaluated as entering the interior of the foundation three-dimensionally) To do.

  According to the inventions according to claims 1 to 6, since the heat storage means includes a latent heat storage material, the heat capacity is large. For example, when heat is collected for underground heat, drilling, pile driving, etc. are carried out deep into the ground. Even if it is not performed, it is possible to store heat in a low shallow layer at low cost in a space-saving manner. And when using heat storage for external devices, such as an air-conditioning / heating device, the fuel can be saved by the clean energy (it does not discharge greenhouse gas) derived from the heat of the ground or the outside air or solar heat. .

  In addition, since the heat storage means includes a plurality of latent heat storage materials having different melting points, when the temperature of the heat storage means rises, latent heat is first stored by the low melting point latent heat storage material, and then sensible heat is stored. After that, when latent heat is stored by the high melting point latent heat storage material, when the temperature of the heat storage means decreases, first, latent heat is released by the high melting point latent heat storage material, then sensible heat is released, and then The latent heat is released by the low melting point latent heat storage material.

  Therefore, even in an environment where the temperature changes throughout the year, the heat storage means can store a sufficient amount of heat over a long period of time, and can stably output the stored heat for a long period of time. Performance is demonstrated effectively.

  ADVANTAGE OF THE INVENTION According to this invention, the thermal storage apparatus which can exhibit high thermal storage performance also in the environment with a temperature change through the year is obtained.

It is explanatory drawing which shows the building where the heat storage apparatus which concerns on the form for implementing invention was used. It is explanatory drawing which shows the heat-medium pipe | tube of the heat storage apparatus of FIG. It is explanatory drawing which shows the form which changed the solid foundation of FIG. 1 into the cloth foundation. It is explanatory drawing which shows the form which changed the air conditioner of FIG. 1 into the floor heating apparatus. It is explanatory drawing which shows the form which added the heat collection structure by a solar panel to the thermal storage apparatus of FIG. It is explanatory drawing which shows the heat-medium pipe | tube of the heat storage apparatus of FIG.

  Embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 shows a heat storage device according to the present invention. This heat storage device 1 is provided for a building 2 located in an area (for example, Nagoya City) where the underground temperature at a depth of 5 m or more is about 15 ° C. throughout the year, a heat storage tank 3, a heat transfer pipe 4, And a heat exchanger 5.

  Building 2 excavates the ground G, lays crushed stones (crushed stone) 6 and casts discarded concrete 7, and forms solid foundation 8 on crushed stone 6 and discarded concrete 7, and then rises of solid foundation 8 Built on top of part 9. A heat insulating material 11 that covers the bottom plate portion 10 of the solid foundation 8 below the building 2 is provided on the inner surface side of the rising portion 9, and a heat insulating material 12 that covers the ground G is provided on the outer surface side of the rising portion 9. Yes. The building 2 is preferably highly airtight and highly heat-insulated. For example, Low-E double glazing is used for windows, and an external heat insulating method is preferably used for roofs and outer walls.

  The building 2 is provided with an air conditioner 13 for indoor air conditioning, and the refrigerant pipe 14 through which the refrigerant flows passes through a heat exchanger 5 provided outside the building 2.

  A concave space surrounded by the lower portion of the rising portion 9 is formed below the bottom plate portion 10 of the solid foundation 8, and the heat storage tank 3 is provided. The heat storage tank 3 contains a latent heat storage material that stores or releases heat using the latent heat associated with the phase transition between the solid phase and the liquid phase, and specifically includes normal paraffin 15 having an average melting point of 12 ° C. A capsule (indicated by □ in the figure) and a capsule (indicated by Δ in the figure) enclosing normal paraffin 16 having an average melting point of 18 ° C. are mixed in the base material 17 and formed. ("Mean melting point" means the average value of the melting point when the paraffin is composed of one kind, and the (additive) mean value considering the weight ratio of each kind of melting point when the paraffin is composed of plural kinds. For example, when a paraffin having a melting point of 10 ° C. and a paraffin having a melting point of 22 ° C. are mixed at a weight ratio of 1: 1, the average melting point is 16 ° C., and the paraffin having a melting point of 10 ° C. and the paraffin having a melting point of 22 ° C. Is mixed at a weight ratio of 5: 1 Expediently, the average melting point will be 12 ° C..). Here, the base material 17 is concrete, but mortar, gypsum, asphalt, resin, or the like may be used as long as it has heat storage properties. Moreover, the dispersion amount and dispersion mode of the normal paraffin 15 and the normal paraffin 16 with respect to the base material 17 are not particularly limited. Here, the normal paraffin 15 having a weight ratio of 5% to the base material 17 and the 5% Normal paraffin 16 is dispersed in the base material 17 at a substantially uniform density.

  As shown in FIG. 2, the heat transfer medium pipe 4 is a circulation circuit that meanders the inside of the heat storage tank 3 in plan view and passes through the heat exchanger 5. Circulates. This water exchanges heat with the refrigerant in the refrigerant pipe 14 in the heat exchanger 5.

  It is conceivable that the heat storage device 1 is operated in summer and winter according to the use time of the air conditioner 13. For example, the three months from July to September are the summer, and the three months from December to the following February are the winter. At the start of operation in the summer, the temperature of the heat storage tank 3 is 12 ° C., all of the normal paraffin 15 or Assuming that most of the solids and the normal paraffin 16 are all solid, and the air conditioner 13 is air-cooled and the heat storage device 1 is operated in July, the water in the heat medium pipe 4 is transferred to the refrigerant pipe in the heat exchanger 5. The refrigerant in 14 is cooled, heated up and returned to the heat storage tank 3. The heat storage tank 3 is in contact with the soil in the ground at about 15 ° C. via the crushed stone 6 and the discarded concrete 7 and is stably kept at a low temperature (lower temperature than the outside air and the water that has been refluxed). It is cooled by exchanging heat with the tank 3, and the heat storage tank 3 receives heat.

  When the cooling operation of the air conditioner 13 and the operation of the heat storage device 1 are continued, the heat storage tank 3 is gradually heated and maintained at 12 ° C. until the normal paraffin 15 is melted, and the temperature rises when the melting is finished. When the temperature of the heat storage tank 3 reaches 18 ° C., the normal paraffin 16 starts to melt, and at the end of September when the cooling operation of the air conditioner 13 and the operation of the heat storage device 1 are stopped, all or most of the normal paraffin 16 becomes liquid. Become. That is, the temperature of the heat storage tank 3 changes from 12 ° C. to 18 ° C. during the three months from July to September, and this temperature of 18 ° C. is maintained for two to three months thereafter.

  Subsequently, in December, when the air conditioner 13 is operated for heating and the heat storage device 1 is operated, the water in the heat medium pipe 4 heats the refrigerant in the refrigerant pipe 14 in the heat exchanger 5, drops the temperature, and stores heat. Reflux to tank 3. The heat storage tank 3 is in contact with the soil in the ground at about 15 ° C. via the crushed stone 6 and the discarded concrete 7 and is stably kept at a high temperature (higher than the outside air or the recirculated water). Heat is exchanged with the tank 3 and heated, and the heat storage tank 3 dissipates heat.

  When the heating operation of the air conditioner 13 and the operation of the heat storage device 1 are continued, the heat storage tank 3 is gradually cooled and maintained at 18 ° C. until the normal paraffin 16 is solidified. When the temperature of the heat storage tank 3 reaches 12 ° C., the normal paraffin 15 begins to solidify, and at the end of February of the following year when the heating operation of the air conditioner 13 and the heat storage device 1 are stopped, all or most of the normal paraffin 15 is solid. become. That is, the temperature of the heat storage tank 3 changes from 18 ° C. to 12 ° C. in the three months from December to February of the following year, and this temperature of 12 ° C. is maintained for the next 4 to 5 months (therefore, further in the summer season) When the air conditioner 13 is cooled and the heat storage device 1 is operated, the above cycle is repeated.

  In this heat storage device 1, since the heat storage tank 3 includes normal paraffins 15 and 16 which are latent heat storage materials, the heat capacity is large, and space saving and low cost can be achieved even without drilling or pile driving deep into the ground. Can store heat from shallow layers. Then, by using the heat storage for heating and cooling the refrigerant of the air conditioner 13, the load of heating and cooling of the refrigerant by the air conditioner 13 itself can be reduced, and the fuel can be saved.

  Further, since the heat storage tank 3 contains two types of normal paraffins 15 and 16 having different melting points, when the temperature of the heat storage tank 3 rises, first, latent heat is stored by the low melting point normal paraffin 15, and then The sensible heat is stored in the normal paraffins 15 and 16 and the base material 17 and then the latent heat is stored in the high melting point normal paraffin 16. On the other hand, when the temperature of the heat storage tank 3 is lowered, first the high melting point normal paraffin 16 is stored. Then, latent heat is released, then sensible heat is released by the normal paraffins 15 and 16 and the base material 17, and then the latent heat is released by the low melting point normal paraffin 15.

  Therefore, even in an environment where the temperature changes throughout the year, the heat storage tank 3 can store a sufficient amount of heat over a long period of time (three months in the above example), and the heat storage device 1 exhibits high heat storage performance. be able to.

  In particular, in the heat storage device 1, the normal paraffin 16 has a melting point of 18 ° C. which is higher than the underground temperature (15 ° C.), and the normal paraffin 15 has a melting point of 12 ° C. which is lower than the underground temperature. In the season, the latent heat is effectively stored by the normal paraffin 16, and in the season when the outside air is lower than the ground temperature, the latent heat is effectively stored by the normal paraffin 15, thereby effectively using the ground heat with high efficiency throughout the year. It is possible to do. It should be noted that the difference between the melting point of the latent heat storage material and the underground temperature is within 5 ° C., preferably 2 to 3 ° C., thereby effectively attracting the underground heat by the heat storage tank 3 and natural heat dissipation from the heat storage tank 3. It is possible to achieve both suppression.

  Furthermore, since the heat storage tank 3 is provided inside the solid foundation 8 in the heat storage device 1, the influence of disturbance by sunlight on the heat storage tank 3 can be suppressed, and above the heat storage tank 3 (on the bottom plate 10). Since the heat insulating material 11 is provided under the floor of the building 2, dew condensation can be prevented.

  Next, referring to other forms, FIG. 3 shows a form in which the building 2 is built on the cloth foundation 18 instead of the solid foundation 8 (the same reference numerals are used for the same parts as in FIG. 1). In this case, the heat storage tank 3 is provided on the crushed stone 19 placed on the ground G, and the upper part is covered with the heat insulating material 20 and the side part is covered with the heat insulating material 21. It has been broken. The heat storage tank 3 is provided inside the fabric foundation 18 by being surrounded by the rising portion 22 and the footing portion 23 of the fabric foundation 18.

  FIG. 4 shows a form in which a floor heating / cooling device 24 is provided in the building 2 instead of the air conditioner 13, and the floor heating / cooling device 24 is a hot / cold water pipe through which water heated or cooled by a heat pump (not shown) flows. 25, and a hot water / cold water panel 25 in which the hot water / cold water pipe 25 meanders in plan view. The hot water / cold water pipe 25 passes through the heat exchanger 5, and the hot water / cold water panel 26 is housed in the under-floor space of the building 2 together with the heat insulating material 27 disposed below the hot water / cold water panel 26.

  The water flowing through the hot water / cold water pipe 25 is heated (winter) or cooled (summer) by the water in the heat medium pipe 4 in the same manner as the refrigerant of the air conditioner 13, thereby heating and cooling by the floor warmer / cooler 24 itself. The load is reduced.

  5 and 6 show a form in which a solar water heater 28 is provided in the building 2. The solar water heater 28 is a hot water in which a solar panel 29 and hot water heated by solar heat collected by the solar panel 29 flow. It has a pipe 30 and a heat exchanger 31 through which the hot water pipe 30 passes. A heat medium pipe 32 is provided inside the heat storage tank 3 independently of the heat medium pipe 4, and valves 33 and 34 are provided on the heat medium pipes 4 and 32, respectively. The heat medium pipe 32 is a circulation circuit that passes through the heat exchanger 31, and water is circulated therein by a driving force of a pump (not shown). This water exchanges heat with the hot water in the hot water pipe 30 in the heat exchanger 31.

  In this form, not only underground heat but also solar heat can be used to suppress a temperature drop of the heat storage tank 3 particularly in winter. That is, in the winter, with the valve 33 open or closed, the valve 34 is opened, and water received from the hot water (heated by solar heat) in the hot water pipe 30 passes through the heat transfer pipe 32. By controlling to circulate, the temperature drop of the heat storage tank 3 is suppressed.

  As mentioned above, although the form for implementing this invention was illustrated, embodiment of this invention is not restricted to what was mentioned above, You may change suitably etc. in the range which does not deviate from the meaning of invention.

  For example, latent heat storage materials include normal paraffin, water, normal paraffin, stearic acid, sodium acetate hydrate, sodium thiosulfate hydrate, sodium carbonate decahydrate, sodium diphosphate, calcium chloride, quaternary Quaternary ammonium salt hydrate, fatty acid triglyceride, polyalkylene glycol heat storage material (including alkylene oxide polymers such as dodecylene oxide, tetradecylene oxide, hexadecylene oxide, octadecylene oxide, etc.), polyglycerol heat storage Materials (including decaglycerin-lauric acid reaction product, decaglycerin-myristic acid reaction product, decaglycerin-palmitic acid reaction product, decaglycerin-stearic acid reaction product, decaglycerin-behenic acid reaction product, etc.), erythritol or xylitol Etc. May not being incorporated into a capsule, it may be used three or more. Moreover, you may make it contain in a base material not as a liquid or solid but as a gel or as a powder.

  The heat medium for transferring the heat of the heat storage tank may be water, air, dimethylsiloxane silicone oil, ethylene glycol, propylene glycol, glycerin, etc., and the latent heat storage material (encapsulated in the capsule) Normal paraffin or the like) may be suspended.

  Further, the heat collection target may not be ground heat, and not only crushed stone, discarded concrete, and solar water heater, but also a heat pipe for ground heat, an air heat pump, or the like may be used as a heat collection means.

  The present invention can be widely used for general structures as well as buildings such as detached houses, apartment houses, office buildings, schools, hospitals and factories.

1 heat storage device 2 building 3 heat storage tank (heat storage means)
4 Heat transfer tube (flow path)
5 Heat exchanger (heat exchange means)
6 Crushed stone (heat collecting means)
7 Abandoned concrete (heat collecting means)
8 Solid foundation (basic)
9 rising part 10 bottom plate part 11 heat insulating material 12 heat insulating material 13 air conditioner (external device)
14 Refrigerant tube 15 Normal paraffin (latent heat storage material)
16 Normal paraffin (latent heat storage material)
17 Base material 18 Fabric foundation (foundation)
19 Crushed stone (heat collecting means)
20 Heat insulating material 21 Heat insulating material 22 Rising part 23 Footing part 24 Floor heating / cooling device (external device)
25 Hot water / cold water pipe 26 Hot water / cold water panel 27 Insulation 28 Solar water heater (heat collecting means)
29 Solar Panel 30 Hot Water Pipe 31 Heat Exchanger 32 Heat Transfer Pipe 33 Valve 34 Valve

Claims (6)

Heat storage means for storing heat collected by heat collecting means for collecting heat of the ground or outside air or solar heat;
A flow path through which a heat medium that moves the heat storage of the heat storage means flows, and
Heat exchange means for performing heat exchange between the heat medium and an external device,
The heat storage device includes a plurality of latent heat storage materials having different melting points. The heat collecting means collects heat in the ground,
At least one of the plurality of latent heat storage materials has a melting point higher than the underground temperature, and the other one of the plurality of latent heat storage materials has a melting point lower than the underground temperature. The heat storage device according to claim 1, wherein   The heat storage device according to claim 2, wherein the heat storage means is provided in an underground thin layer or a building foundation.   At least one of the plurality of latent heat storage materials is water, normal paraffin, stearic acid, sodium acetate hydrate, sodium thiosulfate hydrate, sodium carbonate decahydrate, sodium diphosphate, calcium chloride, Quaternary ammonium salt hydrate, fatty acid triglyceride, alkylene oxide polymer, decaglycerin-lauric acid reaction product, decaglycerin-myristic acid reaction product, decaglycerin-palmitic acid reaction product, decaglycerin-stearic acid reaction product, decaglycerin- The heat storage device according to any one of claims 1 to 3, comprising a behenic acid reactant, erythritol, or xylitol.   5. The heat storage device according to claim 1, wherein at least one of the plurality of latent heat storage materials is liquid, solid, or gel.   The heat storage device according to any one of claims 1 to 5, wherein at least one of the plurality of latent heat storage materials is included in a capsule.

Images