JP2883168B2 - Heat storage device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an ice making machine that supplies brine to generate ice for use as a heat source for cooling or freezing, and the like. The present invention relates to a heat storage device comprising an ice heat storage tank for storing heat.

<Prior Art> A conventional heat storage device is configured to supply brine from an ice heat storage tank to an ice maker, freeze water in the brine, and generate sherbet-like ice.

The cooling brine containing sherbet-like ice stored in the ice heat storage tank is supplied to a use-side heat exchanger used for a cooling or freezing heat source, and the brine from the use-side heat exchanger is removed. Returned to the ice storage tank.

<Problems to be Solved by the Invention> However, as the amount of ice stored in the ice heat storage tank increases, the brine solution concentration increases, the freezing temperature decreases, and the coefficient of performance in an ice machine decreases. However, there is a disadvantage that ice is hardly generated and ice making efficiency is reduced.

Also, even if ice is made in such a state that the ice making efficiency is lowered, the ice and the solution are hardly separated, and the ice filling rate (IPF: Ice Pa
The cking factor can be increased only up to about 50% at the maximum, and there is a disadvantage that the ice heat storage amount is small compared to the volume of the ice heat storage tank.

In addition, when the load on the use-side heat exchanger is low and the flow of brine is reduced, the sherbet-like ice becomes a snow-like solidified state that has solidified on the upper layer of the ice heat storage tank, and the upper surface of the ice If a slight depression occurs, the brine returned from the use-side heat exchanger side concentrates in the depression, ice melts around the depression, and a flowing water channel is formed, and only the flowing water channel has brine. The heat exchange area (contact area) with the ice decreases, the ice content in the brine sent from the ice storage tank to the use side heat exchanger decreases, and the heat exchange efficiency at the use side heat exchanger However, there was a drawback that was reduced. Further, such a phenomenon becomes more remarkable as the thickness of the ice layer solidified on the upper layer side of the ice storage tank becomes thicker, which also makes it impossible to increase the ice filling rate. At the limit.

Further, as an ice heat storage tank, for example, as disclosed in JP-A-60-196596, JP-A-60-196597, JP-A-62-98193, JP-A-63-180088 and the like. To
Some ice storage tanks are filled with a heat storage body containing a coolant, but in any of the techniques disclosed in these publications, the heat storage body is frozen in order to freeze the coolant inside the heat storage body. To supply cold water to the ice thermal storage tank,
When extracting low-temperature energy stored in the ice thermal storage tank, it cannot be transported with frozen water,
The cooling water circulates and flows as a heat medium over the ice heat storage tank and the heat transfer target. For this reason, if the amount of the heat storage body is increased, the amount of the cold water as the heat medium is reduced, and if the cold water is taken out while sufficiently exchanging heat with the heat medium, the circulation flow speed of the cold water must be slowed down. There is a drawback that the amount of cold water per unit time taken out from the unit decreases and the heat exchange efficiency on the user side decreases, while increasing the amount of cold water as the heat medium increases the ice storage temperature of the ice storage tank as described above. There is a disadvantage that the number of ice storage tanks is small for the volume.

The present invention has been made in view of such circumstances, and uses the brine returned from the use-side heat exchanger side and the ice stored in the ice heat storage tank at a high heat exchange efficiency. It is an object of the present invention to provide a heat storage device capable of increasing the ice filling rate in an ice heat storage tank while increasing the content of ice in brine sent to a side heat exchanger.

<Means for Solving the Problems> In order to achieve the above object, the heat storage device of the invention according to claim (1) supplies brine, cools brine, and freezes water in brine. An ice maker that produces sherbet-like ice, an ice heat storage tank that stores a cooling brine containing sherbet-like ice supplied from the ice maker, and an ice heat storage tank that is connected to the ice heat storage tank and contains sherbet-like ice. A supply pipe for supplying the cooled cooling brine to the use-side heat exchanger, and the supply pipe is provided above the ice heat storage tank, and the brine from the use-side heat exchanger is dispersed so as to cover the entire upper surface or almost the entirety of the ice heat storage tank. Supply means for supplying, and in the ice heat storage tank, a large number of coolants in which a liquid having a freezing point higher than brine is sealed in a bag material having heat conductivity, at least the liquid level in the ice heat storage tank or So To be housed in a state that exists near the

Various materials such as a resin material such as polyethylene and a metal material such as copper can be used as the bag material having heat conductivity.

As the liquid to be sealed in the bag material, water may be used, but it is sufficient that the solidification point is higher than that of brine, and various liquids can be used.

Further, in the heat storage device of the invention according to claim (2), the content rate of the coolant [coolant capacity / (coolant capacity + brine capacity)] is set to 10 to 60%. If it is less than 10%, there is no effect, while if it exceeds 60%, the amount of brine as a heat medium decreases and the heat exchange efficiency decreases.

<Operation> According to the configuration of the heat storage device of the invention according to claim (1),
Coolant exists at or near the liquid level in the ice thermal storage tank,
Sherbet-like ice exists in a state where the coolant liquid freezes and enters between the outer peripheral surfaces of the bag material in a three-dimensional direction,
From above the bag material, brine returned from the use side heat exchanger side is supplied, can be dispersed and flow down through many gaps between the bag materials, and the frozen liquid of the coolant and sherbet In addition to ensuring a sufficient heat exchange area with ice in the form of ice, that is, ice stored in the ice heat storage tank, sherbet-like ice can be favorably supplied from the ice heat storage tank to the use-side heat exchanger.

In addition, due to heat transfer from the cooled brine containing sherbet-like ice generated by an ice machine, first, the liquid sealed in the bag material freezes, and the liquid sealed in the bag material freezes. Until the ice is melted, the concentration of brine does not change because the sherbet-like ice is melted and supplied sequentially, and the amount of ice in the brine increases after freezing of the liquid. As a whole, up to a maximum of about 50% of the volume of the liquid making up the coolant and brine can be iced.

According to the configuration of the heat storage device of the invention according to claim (2), considering the ice filling rate when the content of the coolant is 60%, the ice filling rate = the amount of ice / (the amount of coolant) + Brine amount) = 60 + 40 x 50/100 = 80%, and the coolant content is
The ice filling rate in the case of 10% is 10 + 90 × 50/100 = 55%, and an ice filling rate of 55 to 80% is obtained. When heat is transferred, while ice is present in the brine, the ice can be easily transported in a sherbet shape, so that the sherbet-like ice is used as a heat medium, and the ice in the brine is melted. Later, by utilizing the brine solution as a heat medium, heat can be transferred using not only ice of the coolant but also ice in the brine.

<Example> Next, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an overall schematic configuration diagram showing a specific example of the heat storage device of the present invention.

In this figure, reference numeral 1 denotes an ice heat storage tank. In the ice heat storage tank 1, for example, ethylene glycol, glycerin,
Brine, which is an aqueous solution containing a special solution such as propylene glycol, ethanol, and calcium chloride as a solute and using water as a solvent and having a lower freezing point than water and a higher specific gravity than ice, is stored.

An ice making machine 5 is connected to the ice heat storage tank 1 through a first supply pipe 3 provided with a first pump 2 and a first return pipe 4, and the brine in the ice heat storage tank 1 is connected to the ice making machine. 5, the water in the brine is frozen to produce sherbet-like ice, and the ice is returned to the ice heat storage tank 1 via the first return pipe 4, and the low-temperature energy of the sherbet-like ice is stored in ice. It is configured to store in the tank 1.

Although not shown, the ice maker 5 includes a refrigerator (Super Chiller: manufactured by Sunwell Engineering), a compressor, a condenser, and an expansion valve, and circulates and flows the refrigerant in that order.

At the end of the first return pipe 4, a nozzle 4a for dispersion supply is provided.
Are provided so that ice can be supplied in a state of being uniformly dispersed throughout the ice heat storage tank 1.

In addition, the ice heat storage tank 1 is provided with a second supply pipe 7 provided with a second pump 6 and a second return pipe 8, through which a heat source side of the cooling system with the natural circulation of the refrigerant is used. A condenser 9 as an exchanger is connected in communication, and the condenser 9 is connected to the ice heat storage tank 1.
Is supplied with brine containing sherbet-like ice or cooled brine to condense and liquefy the refrigerant vapor supplied to the condenser 9.

At the tip of the second return pipe 8, nozzles 8 a for dispersion supply are attached, and return means is configured to return water from the condenser 9 uniformly over the entire upper surface of the ice heat storage tank 1. ing.

Coolants 10 are stored in the ice heat storage tank 2.

As shown in the cross-sectional view of FIG. 2, each of the coolants 10 is formed by enclosing water 12 as a liquid whose solidification point is higher than that of brine in a spherical bag material 11 made of polyethylene having heat conductivity. The specific gravity is smaller than that of the brine and is configured to float on the entire upper surface of the ice heat storage tank 2.

Coolant 10 content [coolant capacity / (coolant capacity +
The capacity of the brine is set to 40%, so that the ice filling rate can be increased up to 70%.

That is, all of the coolant 10 (for 40%) and brine (60%
It can be frozen up to the total amount (70%) of 30% (60 × 0.5%), which is 50% of the amount of (minute).

From the viewpoint of practical effects and heat exchange efficiency, the content of the coolant is 10 to 60%, thereby reducing the ice filling rate to 55%.
Can be increased up to ~ 80%.

The liquid to be filled in the bag material 11 to constitute the coolant is not limited to water 12, but may be, for example, caustic soda, calcium chloride, sodium carbonate, potassium hydrogen carbonate, higher alcohol, polyhydric alcohol, oil, fat, wax, Fatty acids, etc.
In short, if the liquid has a higher freezing point than brine,
Various materials can be applied.

The heat storage device of the present invention can be applied to a case where freezing is performed in a warehouse or a storage provided with a refrigeration facility.

<Effect of the Invention> According to the heat storage device of the invention according to claim (1), the brine returned from the use side heat exchanger side can be dispersed and flowed down through a number of gaps between the bag materials. Therefore, even if the load on the utilization side heat exchanger is low, the flow of brine is small, and the sherbet-like ice is solidified in the ice storage tank, the frozen liquid of the coolant and A sufficient heat exchange area (contact area) with the sherbet-shaped ice, that is, ice stored in the ice heat storage tank, can be easily separated, and the sherbet-shaped ice can be easily separated and supplied to the use-side heat exchanger. The heat exchange efficiency with the ice stored in the ice heat storage tank can be increased, the ice filling rate can be effectively increased, and the heat exchange efficiency with the use-side heat exchanger can also be increased. it can.

In addition, due to the heat transfer from the cooled brine containing sherbet-like ice generated by an ice machine, first, the liquid sealed in the bag material freezes, and the liquid sealed in the bag material freezes. Until the ice is melted, the concentration of brine does not change because the sherbet-like ice is supplied sequentially even after melting, and the amount of brine ice increases after freezing of the liquid. The ice in the brine is frozen in a state where the concentration of brine in the ice storage tank does not increase, that is, when the coefficient of performance of the ice making machine is high, and then the coolant liquid is cooled. As the coolant liquid freezes, there is no change in the brine concentration, and the ice filling rate can be easily increased without increasing the brine concentration in the ice storage tank. Of ice per unit volume to be stored in Can be increased, for example, in the case of a use as a heat source for cooling, can reduce the installation space can be downsized ice thermal storage tank in order to obtain the thermal energy of the required amount, which is economical.

In addition, since the sherbet-like ice is supplied from the ice heat storage tank as a heat medium to, for example, a use-side heat exchanger such as a condenser as a cooling heat source, the heat can be transferred by the latent heat of melting. It is economical because the amount of heat supplied to the heat exchanger can be reduced and the power for transporting the heat medium can be reduced, especially when the use side heat exchanger is dispersedly arranged away from the ice heat storage tank. It is.

According to the heat storage device of the invention according to claim (2),
Since the content of the coolant is set to 10 to 60%, a sufficient ice filling rate of 55 to 80% can be obtained, and a decrease in the amount of brine as a heat medium is suppressed to reduce the amount of coolant to the use side heat exchanger. Heat exchange efficiency can be improved.

[Brief description of the drawings]

The drawings show an embodiment of the heat storage device according to the present invention, FIG. 1 is a schematic configuration diagram, and FIG. 2 is a sectional view of a coolant. 1 ... ice heat storage tank 5 ... ice maker 7 ... second supply pipe 8 ... second return pipe 8a ... nozzle 10 ... coolant 11 ... bag material 12 ... higher freezing point than brine Water as liquid

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kensuke Tokunaga 4-1-1-13, Honcho, Chuo-ku, Osaka-shi, Osaka Inside the Takenaka Corporation Osaka Main Store (72) Inventor Nozomu Kusumoto 4 Honcho, Chuo-ku, Osaka-shi, Osaka No. 1-113 Takenaka Corporation Osaka Main Store (56) References JP-A-60-134175 (JP, A) JP-A-64-19277 (JP, A) (58) Fields investigated (Int. . ^6, DB name) F25C 1/00 F28D 20/00 F24F 5/00

Claims (2)

(57) [Claims] 1. An ice machine for supplying brine, cooling the brine and freezing water in the brine to produce sherbet-like ice, and a cooling brine containing sherbet-like ice supplied from the ice machine. An ice heat storage tank, a supply pipe connected to the ice heat storage tank and supplying a cooling brine containing sherbet-shaped ice to a use-side heat exchanger, and provided above the ice heat storage tank, Return means for dispersing and supplying brine from the use-side heat exchanger side so as to cover the entire upper surface or almost the entirety of the ice heat storage tank, and a liquid having a freezing point higher than that of the brine in the ice heat storage tank. A heat storage device characterized in that a large number of coolants sealed in a bag material having heat conductivity are accommodated at least in a state of being present at or near the liquid level in the ice heat storage tank. 2. The content of the coolant according to claim 1 is 10%.
Thermal storage device which is ~ 60%.