JPH06207725A - Ice heat storage apparatus - Google Patents

Abstract

PURPOSE:To improve a loading rate of ice in an ice heat storage tank by injecting a fluid, in which a temperature thereof is lower than a solidification point of a heat storage medium and which has a greater specific gravity than that of the heat storage medium and is not dissolved in the heat storage medium, from the lower portion thereof into a cylindrical member on a bottom in the ice heat storage tank, hereby producing powdered ice pieces, and depositing the heat storage medium on an external wall of the cylindrical member for formation of ice of the heat storage medium thereon. CONSTITUTION:An ice heat storage tank 1 is loaded therein with water M being a heat storage medium and with a refrigerant R being a non-aqueous fluid which has a temperature thereof lower than a solidifiaction point of the ice M and has a greater specific gravity than that of the water M. A heat transfer pipe 17 is vertically provided as a cylindrical member so as to surround the periphery of an infection outlet 15 a which opens toward the interior of the ice heat storage tank 1. A refrigrerant pump 11 is cooled and is simplified from a nozzle 15 into the heat transfer pipe 17, and the refrigerant R overflown from an opening formed in the heat transfer pipe 17 at the upper end of the same makes direct contact with the water M. Ice pieces K are produced and are disposed on an external wall of the heat transfer pipe. The ice is grown as clusters L of ice.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice heat storage system for freezing and ice-making a heat storage medium by direct contact between the heat storage medium and a liquid which is below the freezing point of the heat storage medium and does not dissolve in the heat storage medium, and utilizes the heat absorbing action of this ice-making product. Regarding the device.

[0002]

2. Description of the Related Art An air conditioning system equipped with an ice heat storage device is capable of leveling electric power by shifting a part of the electric power demand for cooling concentrated during the daytime in summer to nighttime. In other words, low-cost nighttime electricity is used to store cold heat, and by using this cold heat for air conditioning in the daytime, users can obtain air conditioning with low running costs, while electric power companies can install equipment by peak shifting power demand. The operating rate is improved.

The methods of making ice in the ice heat storage device are roughly classified into a static type in which ice accretion / thawing is performed on the ice making heat exchanger and a dynamic type in which ice is not made to accrete on the ice making heat exchanger.

Generally, the static type has a simple structure, but on the other hand, the heat transfer resistance increases as the ice grows.
While the cooling temperature for ice making has to be gradually lowered, which has the essential drawback of lowering efficiency,
Since the dynamic type can raise the cooling temperature of the refrigerant higher than the static type, the coefficient of performance of the refrigerator is good and there is no need to arrange a heat exchanger in the ice heat storage tank and the filling rate of ice (IPF: Ice Packing Factor)
Also improves.

There are various types in the dynamic type,
At the same time, it is a non-water-soluble liquid (refrigerant) that has a specific gravity of 1 or more at low temperature.
There is a method to make ice by direct contact with water. this is,
The water-insoluble liquid existing at the bottom of the heat storage tank is cooled to 0 ° C. or less and jetted into water through a nozzle arranged in the heat storage tank. Due to the circulation of the cooled water-soluble liquid, sherbet-like ice (ice particles) is generated in the heat storage tank, and this ice rises due to buoyancy and is stored from the upper portion of the heat storage tank and floats. Then, if necessary, the endothermic action when the ice is melted is used for the cooling operation of the air conditioner.

[0006]

However, in the dynamic ice heat storage system as described above, the sherbet-like ice that is generated and floats has almost no compression between the ices, so that the volume ratio of the ice is low. , The IPF was low. Further, heat exchange between the non-water-soluble liquid and water is performed while the non-water-soluble liquid ejected from the nozzle into the water falls in the water, so that the nozzle is arranged so that heat is exchanged from the bottom of the ice heat storage tank. Must be above the required distance. Usually, this fall distance is required to be about 1 m. That is, the area below the nozzle up to about 1 m is the ice making area, and the area above the nozzle is the ice storage area. In this case, the area lower than the nozzle in the ice heat storage tank becomes a dead space, and it is not possible to store ice,
It is a cause of low IPF. If it is attempted to make ice together with ice storage in a region below the nozzle, the nozzle freezes during ice making, and the ejection holes are clogged, making it impossible to supply the refrigerant.

Further, even when the ice storage area is provided only above the nozzle, there is a problem that the ejection hole of the nozzle gradually freezes and grows to clog the ejection hole, making it impossible to continue ice making. .

Therefore, an object of the present invention is to further improve the filling rate of ice in the ice heat storage tank.

[0009]

In order to achieve the above object, the present invention provides a heat storage medium and a liquid having a liquid temperature below the freezing point of the heat storage medium and having a specific gravity larger than that of the heat storage medium and not dissolved in the ice. Stored in a heat storage tank, the bottom of this ice storage tank is connected to one end of a liquid recovery pipe that recovers the liquid and has a cooling means in the middle, and the other end of this liquid recovery pipe is connected to the bottom of the ice storage tank. A jetting means for jetting the liquid is provided, and a tubular member having an open upper end is provided at the bottom of the ice heat storage tank so as to surround the jetting outlet of the jetting means.

[0010]

According to the ice heat storage device having such a configuration, the liquid staying at the bottom of the ice heat storage tank is recovered from the liquid recovery pipe and cooled by the cooling means, and then ejected from the ejection means into the tubular member. To be done. The liquid ejected into the tubular member rises in the tubular member, flows out from the upper end into the ice heat storage tank, and when contacted with the heat storage medium, granular ice is generated, and at the same time, the outer periphery of the tubular member is formed. Due to heat conduction with the heat storage medium that comes into contact with the heat storage medium, the heat storage medium is iced on the outer periphery of the tubular member.

[0011]

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

FIG. 1 is a sectional view showing the overall structure of an ice heat storage device according to an embodiment of the present invention. Inside the ice heat storage tank 1,
Water M, which is a heat storage medium, and below the freezing point of water M, that is, 0 ° C
It is filled with a refrigerant R which is a water-insoluble liquid having a specific gravity larger than that of water M at the following liquid temperature. At the bottom near the side wall of the ice heat storage tank 1, a refrigerant storage part 3 protruding downward is provided, and the refrigerant R having a larger specific gravity than the water M is separated from the water M and most of the refrigerant is deposited in the refrigerant storage part 3. Will exist. One end of a refrigerant pipe 5 as a liquid recovery pipe for recovering the refrigerant R in the refrigerant reservoir 3 is connected to the lower end of the refrigerant reservoir 3. In the refrigerant pipe 5, the refrigerant R is sequentially provided from the refrigerant reservoir 3 side.
A refrigerant pump 11 that circulates the refrigerant and a refrigerator 13 that serves as a cooling unit that cools the refrigerant sent from the refrigerant pump 11 are provided.

The other end of the refrigerant pipe 5 is branched in two directions, and a nozzle 15 as a jetting means for jetting the refrigerant R at each tip thereof.
Is provided. The nozzle 15 is attached to the bottom of the ice heat storage tank 1, and the ejection port 15 a opens inside the ice heat storage tank 1. A heat transfer pipe 17 as a tubular member is vertically provided at the bottom of the ice heat storage tank 1 so as to surround the ejection port 15a. The heat transfer pipe 17 has an opening 17a formed at the upper end, and the opening 17a is located in the water M in the ice heat storage tank 1.

A cylindrical spacer 19 is accommodated in the heat transfer pipe 17 in a state of being fixed to the inner wall of the heat transfer pipe 17 via a plurality of support rods 21 provided at both upper and lower ends. The upper and lower ends of the spacer 19 are closed, the lower end is located away from the nozzle 15, and the upper end is located slightly below the opening 17 a of the heat transfer pipe 17. Spacer 19
An annular refrigerant passage 23 is formed between the outer circumference of the heat transfer pipe 17 and the inner wall of the heat transfer pipe 17.

In the ice heat storage device having such a structure, when the refrigerant pump 11 is driven, the refrigerant R in the refrigerant storage section 3 is driven.
Is cooled to an arbitrary temperature in the refrigerator 13 and supplied from the nozzle 15 into the heat transfer pipe 17. Then, the inside of the heat transfer pipe 17 is filled with the refrigerant R, and the refrigerant R overflowing from the opening 17a at the upper end of the heat transfer pipe 17 makes direct contact with the water M to perform heat exchange, cooling the water M and ice. It flows down to the bottom of the heat storage tank 1 and is guided to and stored in the refrigerant storage unit 3.

When the temperature of the water M reaches 0 ° C. by repeating the above process, the contact between the refrigerant R and the water M causes the generation of ice. A part of the generated ice becomes ice particles (sherbet-like ice) K, and the ice particles K rise in water due to buoyancy and float above the ice heat storage tank 1. Then, when this state is continued, the generated ice particles K are
It is gradually accumulated from the top to the bottom.

On the other hand, in the process in which the refrigerant R supplied from the nozzle 15 rises in the refrigerant passage 23 in the heat transfer pipe 17 and overflows from the opening 15a at the upper end of the heat transfer pipe 15, the refrigerant R in the refrigerant passage 23. Heat-exchanges with the water M in contact with the outer wall of the heat transfer pipe 17 by heat transfer with the heat transfer pipe 17, starts icing on the outer wall of the heat transfer pipe 17, and gradually grows as an ice block L. The refrigerant passage 23 has a spacer 19
Since the passage area is reduced by storing the
The flow velocity of the refrigerant R here is kept high, and the heat transfer efficiency is high. Further, at this time, the refrigerant R in a supercooled state that overflows and falls along the outer wall of the heat transfer pipe 17
In the presence of, will also accelerate the growth of ice that has landed. The ice block L generated on the outer wall of the heat transfer pipe 17 is melted from the outside by the circulation of the water M when the ice is melted.
Additional ice making is possible.

According to such an ice making method, a high-density ice block L is generated on the outer periphery of the heat transfer pipe 17, and the ice heat storage tank 1
The ice particles K are in a state other than the ice blocks L in the inside, and the ice can be generated in the entire region of the water M in the ice storage tank 1, and a high ice filling rate can be obtained. Further, since the heat transfer pipe 17 is filled with the refrigerant R, the nozzle 15 is always immersed in the refrigerant R, and the ejection port 15a of the nozzle 15 is not frozen and clogged. Further, temporarily, ice is deposited on the upper end surface of the heat transfer pipe 17 where the refrigerant R and the water M come into contact with each other,
Even if it grows gradually, the opening 17 on the upper end surface of the heat transfer pipe 17
Since the diameter of a is sufficiently large, the upper end surface of the heat transfer pipe 17 is not blocked during the ice making and the refrigerant R cannot be supplied, and the ice making operation can be performed for a long time.

[0019]

As described above, according to the present invention, in the cylindrical member provided at the bottom of the ice heat storage tank, the liquid temperature is lower than the freezing point of the heat storage medium and the specific gravity is larger than that of the heat storage medium. A liquid that does not dissolve in the medium is ejected from below, and this liquid flows into the ice heat storage tank from the upper end of the tubular member to generate granular ice by contact with the heat storage medium, and at the same time it contacts the outer wall of the tubular member. By heat conduction with the heat storage medium, etc., the heat storage medium is iced on the outer wall of the tubular member.
It is possible to generate ice almost in the entire ice storage tank,
A high ice filling rate can be obtained. Further, since the jetting means for jetting the liquid is constantly immersed in the liquid inside the tubular member, it is possible to prevent icing on the jet outlet.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall structure of an ice heat storage device according to an embodiment of the present invention.

[Explanation of symbols]

 M Water (heat storage medium) R Refrigerant (liquid) 1 Ice heat storage tank 5 Refrigerant pipe (liquid recovery pipe) 13 Refrigerator (cooling means) 15 Nozzle (jetting means) 15a Jet outlet 17 Heat transfer pipe (cylindrical member)

Claims (1)

[Claims] 1. A heat storage medium and a liquid whose liquid temperature is below the freezing point of the heat storage medium and whose specific gravity is greater than that of the heat storage medium and does not dissolve in the heat storage medium are stored in an ice heat storage tank, and at the bottom of this ice heat storage tank,
One end of the liquid recovery pipe for recovering the liquid and having a cooling means in the middle is connected, and the other end of the liquid recovery pipe is provided with ejection means for ejecting the liquid from the lower portion in the ice heat storage tank. An ice heat storage device, characterized in that a cylindrical member having an open upper end is provided at the bottom of the ice heat storage tank so as to surround the outlet.