JPH05203202A - Cold storage device - Google Patents

Abstract

PURPOSE:To enhance heat exchange efficiency by a method wherein, in a device wherein a phase-changeable material which is insoluble in an aqueous medium and melts at a temperature higher than that of the medium is dispersed in the aqueous medium to form a dispersion liquid for use as heat storage material, the a mount of the dispersion liquid is detected to control a feed water means. CONSTITUTION:A heat exchanger 11 of a heat source (heat pump) 12 is provided in a heat storage tank 1 accommodating a heat storage material 15 and a heater 14, as an auxiliary heat source, is provided. In heat storage layers 15, a dispersion liquid is used, in which a dispersion phase (paraffin, fats and oils, etc.) is dispersed in a continuous phase (aqueous solution of ethylene glycol, water, etc.), said dispersion phase having melting point higher than that of the continuous phase. In a cooling operation, the material 15 is cooled to a temperature lower than the melting point of the dispersion phase by means of the exhanger 11 being an evaporator and the material 15 is sent to a radiator 9 by a pump 9 to obtain cold air. On the other hand, in a heating operation, the material 15 is heated by the exchanger 11 and heater 14 and the material 15 is sent to the radiator 9 to obtain hot air. In this case, the amount of continuous phase which is easily evaporated from the material 15 is detected from the output of a water level sensor 2 to control the introduction of city water using a cross valve 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a latent heat storage material (hereinafter, referred to as "PC.
M. ". ) Is used to store heat (store cold) or convey heat (or system).

[0002]

2. Description of the Related Art A conventional cold energy storage device ("cold heat storage system")
(Also called), has adopted a dynamic ice making method to make ice in the form of a slurry. This method requires a dispersing section having a very complicated structure, and the slurry ice produced by this method tends to agglomerate and cannot be generally transported.

In general, another cold heat storage device could not convey the latent heat storage material to the radiator. As shown in FIG. 2, the ice-on-coil regenerator is a regenerator tank 2.
1 has an ice making coil 22 and is filled with water 23 so as to cover the ice making coil 22. The water around the ice making coil 22 is cooled and solidified by the heat from the heat source 24,
Ice 230 adheres to the ice making coil 22 (see B in FIG. 2). In this ice-making state, the cooled water 23 in the heat storage tank 21 is sent to the terminal 26 such as a fan coil by the circulation pump 25 for cooling, and then returned to the heat storage tank 21. In this device, the water 23 is the ice making coil 22.
A liquid phase-solid phase transition occurs in the surroundings of, but the water is not transported to the radiator in the state of undergoing the phase transition, but cooled water is transported. In ice-making devices such as the ice-on-coil method and heat storage capsule type, the latent heat storage material is a stationary body, so the heat exchange efficiency during ice making / thawing is poor, and the effective latent heat amount decreases accordingly (the heat storage tank is large. In addition, if the ice making pipes are extremely long,
Since the surface area of the heat storage material needs to be extremely large, there is a drawback that the cost becomes very high.

In order to eliminate such drawbacks, a cold heat storage device has been considered in which a dispersion liquid (emulsion or suspension) obtained by dispersing a phase change material in a liquid having a lower melting point than that is used as a latent heat storage material. In this device, since the dispersion medium can hold the liquid phase even when the phase change material is in the solid phase, the dispersion liquid is conveyed to the radiator,
Therefore, after exchanging heat such as latent heat with the outside, it can be returned to the heat storage tank. However, when the latent heat storage material has only one melting point, for example, a cooling melting point, only heat storage type cooling can be performed.

In order to perform both heat storage type cooling and heating with one device, it is necessary to mix the dispersion with a phase change material having a heating melting point different from the cooling melting point.
However, such a dispersion has a drawback that the heat storage material content (dispersed phase content) exceeds 50%, so that the transport performance is considerably deteriorated and the heat storage tank capacity of the apparatus is increased.

On the other hand, as shown in FIG. 3, it is also conceivable to perform both heat storage type cooling and heating by using a cold storage device having a low melting point heat storage material tank 31a and a high melting point heat storage material tank 31b. Into the low melting point heat storage material tank 31a, a dispersion liquid (emulsion heat storage material for cooling (or cool storage material)) 32a in which a phase change material having a melting point for cooling is dispersed is put,
A high-melting point heat storage material tank 31b is filled with a dispersion liquid (emulsion heat storage material for heating) 32b in which a phase change material having a heating melting point is dispersed, and three-way valves 33 and 34 are switched to operate them by a pump 35. Either one of them is sent to the terminal 40 such as a fan coil to perform cooling (when the emulsion cold storage material 32a is sent) or heating (when the emulsion heat storage material 32b is sent), and then each heat storage tank 31.
It is designed to return to a and 31b. Each tank 31a,
A cooling coil 38a and a heating coil 38b, to which the heating / cooling source 36 is connected, are provided at 31b.
37 is an outdoor unit, 39a is a pipe for emulsion cold storage material 32a, 39b is a pipe for emulsion heat storage material 32b.
However, in this device, since both the emulsion cold storage material 32a and the emulsion heat storage material 32b are used, there is a drawback that the heat storage tank capacity becomes large (for example, doubled).

[0007]

A cold storage heat storage device for heating by utilizing the sensible heat of an emulsion cold storage heat storage device is compared with a cold storage heat storage device using an emulsion storage heat storage material having two melting points for cooling and heating. The advantage is that it is not necessary to increase the heat storage tank capacity. However, in a device that uses the sensible heat of the emulsion regenerator material, since the dispersion liquid becomes a high temperature (for example, 60 ° C. or higher) during heating, water or the like that is a continuous phase easily evaporates, and the emulsion is separated and destroyed. There were drawbacks such as easy to do.

In view of the above drawbacks, it is an object of the present invention to provide a cold storage heat storage device which has a high heat exchange efficiency, a simple ice making device, and which can be used for both heating and cooling.

[0009]

In order to solve the above-mentioned problems, the present invention is characterized in that a heat storage tank having a heat exchanger inside and a heat storage material is connected to a heat radiator by a pipe, and the heat pipe is connected in the pipe. A heat storage material is designed to flow, and as the heat storage material, a dispersion liquid in which a phase change material that is insoluble in this medium and melts at a higher temperature than the medium is dispersed in an aqueous medium that is a continuous phase is used. In the cold heat storage device, the heat storage tank has a means for detecting the amount of the dispersion liquid inside and a water supply means that operates in conjunction with the detecting means. provide.

The means for detecting the amount of the dispersion liquid in the heat storage tank is, for example, a water level sensor, but is not limited to this. The water supply means is a device that supplies water into the heat storage tank. Water is city water such as tap water. The water supply means operates in conjunction with detection means such as a water level sensor. For example, the valve of the water supply pipe is appropriately opened by an electric signal from the water level sensor to supply water to the heat storage tank. In this way, a constant water level is maintained inside the heat storage tank. When the dispersion liquid in the heat storage tank is supplied with water while being stirred, the dispersion liquid is used for heating without being separated and destroyed.

The stirring is carried out by a simple dispersing means (dispersing section) provided in the heat storage tank. A simple dispersion means is, for example, a pipe for taking out the dispersion liquid from the upper part (or the lower part) of the heat storage tank and returning it to the lower part (or the upper part) of the heat storage tank, and a pump (or a circulation pump) for passing the dispersion liquid into the pipe. )
And / or a stirring impeller arranged in the heat storage tank. If the pump and the impeller are linked with the operation of the water supply means, it becomes easy to supply water while stirring the dispersion liquid.

As the continuous phase, for example, an aqueous solution such as an ethylene glycol aqueous solution or a propylene glycol aqueous solution, or an aqueous medium (or liquid) such as simple water is used. As the dispersed phase, a phase change material that melts (or solidifies) at a temperature higher than that of the medium of the continuous phase (phase change material having a high melting point (freezing point)) is used, and for example, it is insoluble in the medium of the continuous phase. Something, paraffin,
Examples include fats and oils, olefins, and the like. As the phase change material, for example, a material having an appropriate melting point according to the heat radiation temperature to be used is used.

When the phase change material which is the dispersed phase is melted, the latent heat storage material is an emulsion, and when it is solidified, the latent heat storage material is a suspension. In the present invention, for example, the melting point of the phase change material in the dispersion is for cooling (for example, melting point is about 20 ° C. or lower), and the sensible heat of the heat storage material is used for heating. As the radiator, for example, a heat exchanger is used, but the radiator is not limited thereto. The radiator dissipates heat from the latent heat storage material and / or absorbs heat from the latent heat storage material.

[0014]

When a dispersion liquid (emulsion cold storage material) in which a phase change material having a melting point for cooling is dispersed in an aqueous medium is used as the dispersion liquid to be put in the heat storage tank, the emulsion cold storage using a low melting point is used during cooling. The material is cooled in the heat storage tank to solidify the phase change material and transported in this state,
In the heat radiation part, the heat of fusion of the phase change material is used for cooling, and the emulsion cold storage material is returned to the heat storage tank.

On the other hand, during heating, the sensible heat of the emulsion regenerator material is used. That is, the heat is stored in the heat storage tank due to the temperature rise of the emulsion regenerator material (the phase change material is melted), the heat is conveyed in this state, and heating is performed by lowering the temperature of the phase change material and the dispersion medium in the heat radiating section. Then, the emulsion regenerator material (the phase change material remains molten) is returned to the heat accumulator.

When the emulsion regenerator material is heated to a high temperature during heating by utilizing sensible heat, the continuous phase is likely to evaporate because the continuous phase is an aqueous medium. Therefore, by detecting the water level of the entire tank and supplying water while stirring so as to maintain a constant water level, the emulsion regenerator material can be used for heating without being separated and destroyed.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment thereof, but the present invention is not limited to the following embodiments. FIG. 1 shows one embodiment of the cold energy storage device of the present invention. As shown in FIG. 1, this cold storage device is provided with an evaporator (heat exchanger 11) of a heat source (heat pump 12) inside the heat storage tank 1 to cool the heat storage material 15 in the tank. The heat source has a structure that also serves as a heat source with the four-way valve 13, and the heater 14 is provided in the heat storage tank 1 as an auxiliary heat source.

The heat storage tank 1 and the radiator (cooling / heating fan coil unit) 9 are connected by a pipe 8, and a pump (or circulation pump) 7 is provided in the middle of the pipe 8. As the heat storage material 15, a disperse phase (paraffin, oil, fat, etc.) having a higher melting point (freezing point) than the continuous phase is added to the continuous phase (ethylene glycol aqueous solution, propylene glycol aqueous solution, or just water).
An emulsion (or suspension) in which an olefin or the like is dispersed is used.

At the time of cooling, the heat storage material 15 is used in the heat exchanger 11.
Is cooled below the melting point of the dispersed phase contained therein (for example, when tetradecane is contained in the dispersed phase, about 5 ° C.) or lower (in this case, the continuous phase is set to a temperature at which it does not solidify), and the heat storage material 15 is cooled. The pump 7 sends it to the radiator 9 to obtain cool air, and returns the heat storage material 15 to the heat storage tank 1. Cooling can be performed by continuing this circulation.

During heating, a water level sensor (water level detector) 2 for detecting the water level in the heat storage tank 1, and a water level sensor 2
A water supply device 3 that operates in conjunction with is provided, and the sensible heat of the emulsion heat storage material 15 is heated to a high temperature (for example, about 60 ° C.) by the heat exchanger (condenser) 11 or the auxiliary heat source 14 switched to heating. To use. In this case, the heat storage material 15 is circulated through the radiator 9 while heating is performed while detecting the amount of the continuous phase (for example, water) that easily evaporates from the heat storage material 15 at each water level. At this time, in a simple dispersion unit, from the water supply device (three-way valve) 3 provided to supply water in conjunction with water level detection, the city water 1
Stir every time 0 is supplied.

The above-mentioned simple dispersion part is composed of a pipe 5 and a pump (circulation pump) 4 which are taken out from the upper part (or the lower part) of the heat storage tank 1 and returned to the lower part (or the upper part) of the heat storage tank 1.
The pump 4 is linked with the operation of the water supply device 3 (in the order of water supply and circulation). Further, another example of the simple dispersion unit is composed of the stirring impeller 6 arranged in the heat storage tank 1. The impeller 6 interlocks with the operation of the water supply device 3 (water supply / circulation).

[0022]

According to the cold heat storage device of the present invention, the emulsion heat storage material for cooling can also be used for heating.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of one embodiment of a cold energy storage device of the present invention.

FIG. 2 is an explanatory diagram of an example of a conventional cold energy storage device.

FIG. 3 is an explanatory view of another example of a conventional cold storage heat storage device.

[Explanation of symbols]

 1 Heat Storage Tank 2 Water Level Sensor 3 Water Supply Device (Three-way Valve) 4 Pump 5 Piping 6 Stirring Impeller 7 Pump 8 Piping 9 Radiator (Fan Coil Unit for Cooling and Heating) 10 City Water 11 Heat Exchanger 12 Heat Pump 13 Four-way Valve 14 Heater 15 Heat Storage Material

Claims (1)

[Claims] 1. A heat storage tank having a heat exchanger inside and containing a heat storage material is connected to a radiator by a pipe, and the heat storage material is allowed to flow in the pipe. As the heat storage material,
A cold storage device in which a dispersion liquid in which a phase change material that is insoluble in this medium and melts at a higher temperature than the same medium is dispersed in an aqueous medium serving as a continuous phase is used, wherein the heat storage tank is
A cold-storage heat storage device comprising: a means for detecting the amount of the internal dispersion liquid; and a water supply means that operates in conjunction with the detection means.