JPS59212690A - Heat accumulation and hot water supply system - Google Patents

Abstract

PURPOSE:To enhance the heat exchanging efficiency to improve the heat accumulating capability and hot water supply capability by providing a heat exchanger between heated water in a hot water tank and thermal medium in the bottom of the hot water tank where the temperature is the lowest. CONSTITUTION:Under a heat accumulation mode, the low temperature water 11 to be heated existing in the bottom of a hot water tank 5 is sucked from the lower end of a suction pipe 36 to be fed into the inner pipe 26 of a heat exchanger 21 disposed in the bottom of the tank, and after exchanging heat with a high temperature thermal medium which is circulated from a solar heat collector 24 into an external case 22, is poured to the liquid surface side of the hot water tank 5 through a vertical communicating pipe 19. Under a hot water supply mode, three-way valves 31, 32 are switched to allow the high temperature heated water in the upper part to be drawn into the inner pipe 26 of the heat exchanger 21 through the communicating pipe 19 to be further heated, the heated water being supplied to a hot water supply unit 43 via a pump 34 and a thermowax valve 41, or via a proportionally controlled boiler 42 when the temperature is low. In this manner, the heat exchanging efficiency can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat storage hot water supply system, and more specifically, the present invention relates to a heat storage hot water supply system, and more specifically, it stores heat possessed by a heat medium supplied from a solar heat collector 4, etc. as hot water, and supplies hot water as needed. Regarding heat storage hot water supply equipment.

Heat-storage water heating equipment is known that can supply hot water using heat obtained from solar collectors or waste heat from heat pumps, and store excess heat as hot water to meet demand for hot water or space heating. . In this type of thermal storage hot water supply equipment, a hot water storage tank for storing heated water is likely to be placed under the floor of a house because the underfloor area is less affected by changes in outside temperature.

Therefore, in order to secure a certain amount of heat storage capacity and provide stable hot water supply, for example, 400
! A certain amount of hot water storage capacity must be ensured, such as requiring a capacity of approximately 1,000 liters, and the shape of the hot water storage tank placed under the floor must be flat. In other words, a flat shape is advantageous to effectively utilize the space under the floor, and it is difficult to install a vertical hot water storage tank by digging into the soil under the floor because it is a heavy construction work. be.

By the way, if the hot water storage tank is made flat, the height of the hot water storage tank will be low relative to the overall capacity of the hot water storage tank, and the temperature difference in the height direction of the heated water in the hot water storage tank tends to be small. In addition, heat exchange with the heat exchanger (radiator) is performed only in a part of the tank, which tends to cause dead areas around the tank. Therefore, sufficient natural convection of the heated water within the tank due to the temperature difference in the height direction of the heated water cannot be expected. Therefore, the heat exchange efficiency was low, and the entire capacity of the hot water storage tank was not fully utilized.

] However, when a flat hot water storage tank is placed under the floor, heat exchange efficiency may be low due to insufficient natural convection within the hot water storage tank.

An object of the present invention is that even if the hot water storage tank has a flat shape, the heat exchange efficiency is high because the overall convection of the heated water in the hot water storage tank is sufficient. The objective is to provide heat storage hot water supply equipment with excellent capacity and hot water supply capacity.

Therefore, in the present invention, a heat exchanger for exchanging heat between the water to be heated and a heat medium in the hot water storage tank is installed at the bottom of the hot water storage tank where the temperature is easily the lowest. The hot water on the bottom side (low temperature side) of the hot water storage tank is forcibly circulated to the heat exchanger by a circulation means to ensure a temperature difference between the heat exchanger and the hot water to improve heat exchange efficiency, and When supplying hot water, the upper side of the hot water storage tank (
The heated water on the high temperature side is supplied to the water heater so that the highest temperature heated water in the tank is supplied to the water heater, and in addition, natural convection due to the rise of the heated water on the bottom side Furthermore, in some cases, when hot water is supplied, the water to be heated in the hot water storage tank is heated again when it passes through the exchanger and then supplied to the water heater, thereby achieving the above purpose. This is what we are trying to achieve.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows an embodiment of the heat storage water heater according to the present invention. In the figure, a floor 2 of a building 1 such as a general residence is supported on a cloth foundation 3, and the space under the floor is Several underfloor spaces 4 are defined by the cloth foundation 3.

A hot water storage tank 5 is installed in the underfloor space 401K. ,, The hot water storage tank 5 is formed into a bag shape from a synthetic resin sheet or the like with insulation quilting pasted on the outer circumferential surface, and a fitting 7 is attached to the opening of the hot water storage tank 5 via a cap 6. . On the other hand, an opening 9 to which a lid 8 is removably attached is formed in the floor 2, and maintenance of the control equipment, piping, etc. of the hot water storage tank 5 can be performed through this opening 9. Moreover, this tank 5 can be stored in the underfloor space 4 in a folded state.

The hot water storage tank 5 is filled with a predetermined amount of heated water 11, and the head pressure of the heated water 11 causes the hot water storage tank 5 to be expanded into a flat shape. Further, the hot water storage tank 5, which has expanded into a flat shape, is placed on a subfloor surface 13 via a heat insulating mat 12. The hot water storage tank 5 is surrounded by the cloth foundation 3, and the gap between the hot water storage tank 5 and the cloth foundation 3 is filled with a heat insulating material 14 such as foam beads. Tank 5 is cloth foundation 3
It is well-shaped.

Heated water 11 in the hot water storage tank 5 is supplied into the tank 5 through a water supply pipe 15 . Is the water supply/zobe 15 attached to the upper end of the tank 5? - Is it connected to Rutatsu 7'16? - An introduction pipe 17 whose tip water supply port faces the bottom position of the hot water storage tank 5 is connected to the lutta 7'16,
The water to be heated 11 supplied from the water supply noquig 15 is supplied to the bottom side of the hot water storage tank 5 through the Dale Tatsuzo 16 and the introduction via 17, and the heated water in the hot water storage tank 5 is heated by the action of the water tank f16. The filling capacity of 11 is maintained at a predetermined amount.

A heat exchanger 21 is attached to an anchor 20 at the bottom of the hot water storage tank 5.
It is installed through In this case, heat exchanger 2
If 1 is made of steel, an anchor can be omitted. heat exchanger 2
1 has a double pipe structure, and a heat medium via 23 is connected to an outer case 22, and a solar heat collector 24 placed on the roof of the building 1 is connected via this heat medium pipe 23. is connected. A heat medium circulation pipe 25 is provided in the middle of the heat medium pipe 23, and the heat medium is appropriately circulated between the solar heat collector 24 and the outer case 22 of the heat exchanger 21 from this bong 7'2]C. It is configured to be

On the other hand, heated water 11 is passed through the inner pipe 26 of the heat exchanger 21, and heat exchange is performed between the heated water 11 and the heat medium circulating inside the outer case 22. Efforts may be made to ensure that the amount of time (time) exceeds a predetermined amount.

An upper and lower connecting tube 19 is connected to one end of the inner tube 26. The tip of this upper and lower connecting pipe 19 is the heated water 11
The inner tube 26 is opened near the liquid level of the mother inlet 19.
The heated water 11 in the upper part of the hot water storage tank 5 is sucked, or the heated water 1 in the inner pipe 26 is drawn from the mother inlet 19.
1 is discharged to the upper side of the tank 5.

O, the other end side of the inner pipe 26 is connected to the first port 31A of the first three-way switching valve 31 and the second
The first ports 32A of the three-way switching valves 32 are connected to each other. The second port 31B of the first three-way switching valve 31 is connected to the hot water supply cylinder 7° 34 via the circulation/'P valve 33,
The third port 31C is connected to a pumping pipe 36 via a pumping pipe 35. The lower end opening of the pumping pipe 36 is arranged on the bottom side of the hot water storage tank 5, and the water to be heated 11 on the bottom side inside the hot water storage tank 5 is pumped up through the pumping pipe 36. 1. The first three-way switching valve 31 is equipped with a valve switching motor 37, and this motor 37 connects the first port 31A and the second port 31B during hot water supply (operation), so that heat can be stored. During (operation), the second port 31B and the third port 31C
The switching operation of the valve is performed so that communication is established between the two.

On the other hand, the second port 32B of the second three-way switching valve 32 is connected to the thermowax pulp 41 via the hot water supply nozzle 38, and the third port 32C is connected to the hot water supply cylinder f34 via the circulation nozzle 33. It is connected. E. The second three-way switching valve 32 is equipped with a valve switching motor 3→.When the switching operation of the valve is performed by which valve switching motor 39, the first three-way switching valve 32 is operated. ．． j? The second port 32'B and the third port 32C are configured to communicate with each other during hot water supply (operation).

Said hot water pie! 3B is branched into two at 410 points of thermowax pulp, and one of the hot water supply pipes 38 is provided with a proportionally controlled water heater 42. After the bifurcated hot water supply via '38 is reconnected, it is connected to a water heater 43 such as a shower or a hot water faucet. A circulation means for forcibly circulating the heated water on the bottom side of the hot water storage tank 5 to the heat exchanger 21 during heat storage is configured, and the three-way switching valve 31, 32 and the hot water supply cylinder f34 are used to circulate the heated water on the bottom side of the hot water storage tank 5 during hot water supply. A hot water supply means for supplying the heated water 11 on the side to the water heater 43 is configured.

Next, the operating method of this embodiment will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows the paths of the heat medium and heated water during heat storage operation. During heat storage, the first switching valve 31 is switched so that the second port 31B and the third port 31C communicate with each other, and the second three-way switching valve 32
In this case, the valve is switched so that the first port 32A and the third port 32C communicate with each other. As a result, pumping pipe 3
Low-temperature heated water 11 from the bottom side of the hot water storage tank 5 is pumped up through the lower end opening of the hot water tank 6, and this pumped heated water 11 is transferred to the two switching valves 31, 32 and the hot water supply bong 7''.
The heat exchanger 21 is supplied to one end of the inner pipe 26 of the heat exchanger 21 via the circulation pipe 30 via the pipe 34 .

The water to be heated 11 supplied to the inner pipe 26 is heated by exchanging heat with the high-temperature heat medium circulating in the outer coolant 22, and then passed through the upper and lower connecting pipes 19 to the upper side of the hot water storage tank 5 (at the liquid level). side)
is discharged. At this time, the heated water 11 that exchanges heat with the high-temperature heat medium in the heat exchanger 21 is at a low temperature on the bottom side of the hot water storage tank 5 that has been pumped up into the pumping pipe 36, so that the heated water 11 exchanges heat with each other. The temperature difference between the heated water 11 and the heat medium is large, and the heat exchange efficiency is high.
, FIG. 3 shows the route during hot water supply operation, and in this case, in the first three-way switching valve 31, the first=j? −
) 31A and the second port 31B are communicated with each other,
In the second three-way switching valve 32, the second port 32B and the third port 32C communicate with each other. During hot water supply, high-temperature heated water 11 on the upper side of the hot water storage tank 5 flows through the upper and lower connecting pipes 1.
9 into the inner tube 26 of the heat exchanger 21,
It is supplied to the thermowax pulp 41 via two three-way switching valves 31 and 32 and a hot water pump f34. That is, the heated water 1 in the hottest part of the hot water storage tank 5
1 is supplied to the 1-MOWAX pulp 41. When being supplied to the Thermowax pulp 41, the water to be heated 11 is passed through the heat exchanger 21 and receives the heat of the heat medium. The temperature will be further increased.

The heated water 11 supplied to the thermowax pulp 41 is supplied to the water heater 43 via the proportional control type water heater 42 when its temperature is lower than a predetermined value; If the value is already high, the water is supplied directly to the water heater 43 without passing through the proportional control water heater 42.

Moreover, in this way, the water to be heated 1 in the water heater 43
1 is consumed and the liquid level in the hot water storage tank 5 falls,
The sol tap 16 opens and new water to be heated 11 is supplied to the vicinity of the bottom of the hot water tank 5 through the introduction via 17, and the liquid level in the hot water tank 5 is always kept constant.

According to this embodiment, during heat storage operation, the lowest temperature heated water 11 in the hot water storage tank 5 is transferred to the heat exchanger 2.
1, the heat exchange efficiency in the heat exchanger 21 is high. Therefore, even if the hot water storage tank 5 has a flat shape and natural convection is generally not sufficient,
It has the effect of having a high heat storage capacity. In particular, in this embodiment, heat exchange is performed by forced circulation using the hot water pump f34, so rather than partial heat exchange within the hot water storage tank 5, heat exchange is performed throughout the entire hot water storage tank 5 (throughout the entire hot water storage tank 5) by circulating flow. ) Heat exchange can be performed, further improving heat storage efficiency.

Furthermore, even during hot water supply operation, the heated water 11 in the upper part of the tank 5, which is the highest temperature part of the hot water storage tank 5, is supplied to the water heater 43. (heated water 11) can be obtained, and the hot water supply ability is also excellent.

Furthermore, the heated water 11 on the second side of the hot water storage tank 5 that is supplied to the water heater 43 is further supplied to the water heater 43 after receiving and removing heat from the heat medium in the heat exchanger 21. , Also from this point of view, the hot water supply capacity can be excellent.

By arranging the shattered heat exchanger 21 in the hot water storage tank 5, the heat of the heat medium radiated from the outer case 22 can be recovered by the heated water 11 around the heat exchanger 21, Therefore, in this respect as well, the heat storage capacity and hot water supply capacity can be improved.

In addition, there is an effect that natural convection within the hot water storage tank 5 is caused by the rise of the heated water that has been heated by heat radiation from the outer case 22. That is, by installing the heat exchanger 21 on the bottom side of the hot water storage tank 5, not only forced circulation but also natural circulation can be expected, and from this point of view as well, the heat storage capacity and hot water supply capacity are improved.

Furthermore, for example, when the heat exchanger 21 is installed on the outside of the hot water storage tank 5, a heat insulating material, a heat retention mechanism, etc. are required to prevent the heat held by the heat medium from being radiated to the outer circumferential side of the outer case 22. If the heat exchanger 21 is placed inside the hot water storage tank 5, there is no need for a heat insulating material, which is extremely convenient.

In addition, a flexible hot water storage tank 5 is arranged in the underfloor space 4 defined by the cloth foundation 3, and the cloth foundation 3 is effectively utilized to form a heat insulating layer in the underfloor space 4 and to expand the hot water storage tank 5. It has the effect of being easy to construct without requiring shape preservation or other extensive construction work. In addition, by arranging the heat transfer pipe 23 on the outside of the +) J3 Q% material 1 and communicating with the hot water storage tank 5 by just penetrating three pipes, it is possible to prevent liquid leakage in the unlikely event of an accident. The damage only occurs outdoors, and it is easy to break and repair.

In addition, during hot water supply, the heated water 11 on the upper side of the hot water storage tank 5 may be simply supplied to the water heater 43 without passing the heat medium from the heat collector 24 to the heat exchanger 21. . However, if the temperature of the heat medium is higher than the water to be heated 11, the temperature of the water to be heated 11 can be further increased as described above by passing this heat medium through the heat exchanger 21.

Alternatively, heat radiation from the lid 7 may be particularly prevented by attaching a heat insulating material to the lid 7 or placing foam beads or the like on the lid 7. In addition, although the heat exchanger 21 is described as having a double-tube structure, the present invention is not limited to this. For example, the heat medium flow path may be formed in a spiral shape to form one circular tube structure as a whole. The center portion may correspond to the inner pipe 26 as a flow path for the heated water 11, or
It may have a structure in which heated water 11 is passed through the outer case 22 and a heat medium is circulated through the inner tube 26, or it may have a triple tube structure.

In addition, although the heat medium circulated in the heat exchanger 21 is the heat medium heated by the solar heat collector 24, it is possible to use the heat medium instead of the solar heat collector 24, or In addition, the reheat source may be one that connects the exhaust heat side of the heat pump and also uses the exhaust heat of the heat pump, or one that uses geothermal heat or domestic waste heat, etc., but is not specified in the above cases. do not have. In addition, a coil or the like is arranged in the hot water storage tank 5 in addition to the heat exchanger 21, and the heat in the hot water storage tank 5 collected by the coil or the like is used to operate a heater or the like. You can also do this.

In addition, the hot water storage tank 5 is not limited to a flexible, flat-shaped tank that is placed under the floor, but may also be a tank that is placed somewhere other than under the floor, a vertically long tank, or a rigid tank that maintains a certain shape. There may be. Furthermore, the proportional water heater 42 is not necessarily required.

As described above, according to the example of the present invention, it is possible to provide a heat storage hot water supply equipment with high heat exchange efficiency and excellent heat storage capacity and hot water supply capacity.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the heat storage hot water supply device according to the present invention, and FIGS. 2 and 3 show the paths of the heat medium and heated water during the heat storage operation and hot water supply operation of the embodiment, respectively. FIG. l...Building, 2...Floor, 3...Fabric foundation, 4...
Underfloor space part, 5... Hot water storage tank, 11... Heated water, 12... Heat insulation mat, 13... Underfloor surface, 14.
...Insulation material, work 5...Water supply nozzle, 16...Ball tap, 17...Introduction 71° igu, 19...Upper and lower connecting pipe, 2o...Anchor, 21...Heat exchange vessel, 2
2... Outer case, 23... Heat medium pipe, 24...
・Solar heat collector, 25...heat medium circulation pump, 2 (5
...Inner pipe, 30...Circulation pipe, 31゜32...
First and second three-way switching valves, 31A, 32A...first port, 31B, 32B...second port, 31C, 3
2C...Third port, 33...Circulation/guino, 34
...Hot water pump, 35...pumping, Guino, 36.
・・Kumiai riser pipe, 41・・Thermo wax valve, 4
2...Proportional control type % type %

Claims (1)

[Claims] (1) A heat exchanger that performs heat exchange between the heated water in the hot water storage tank and a heat medium and is installed at the bottom of the hot water storage tank, and the heated water on the bottom side of the hot water storage tank during heat storage. A heat storage hot water supply facility comprising: a circulation means for forcibly circulating water to the heat exchanger; and a hot water supply means for supplying heated water from the upper side of a hot water storage tank to a water heater during hot water supply. (2. In claim 1, the hot water supply means is connected to the discharge side of the heated water of the heat exchanger during hot water supply, and the heated water is supplied to the water heater through the heat exchanger during hot water supply. A heat storage hot water supply facility characterized in that it is configured to