JPH08285418A - Method for discharging supercooled water in supercooling ice making system - Google Patents

Abstract

PURPOSE: To prevent a pipe from being clogged with occurrence of and growth of ice at a discharging port of a pipe for discharging supercooled water to a heat accumulative tank during a supercooling ice making operation. CONSTITUTION: A discharging port 6 of a discharging pipe 5 for use in discharging supercooling water cooled down to supercooled state by an ice making heat exchanger 3 into a heat accumulative tank 1 is installed within water in the heat accumulative tank 1. The water contained in the heat accumulative tank 1 is supplied to an ice making heat exchanger 3 with a circulating pump 7 and cooled to a supercooled state, thereafter the water passes through the discharging pipe 5 and is discharged into the heat accumulation tank through the discharging port 6. The supercooled water changes its phase into ice during a process in which the water ascends from the discharging port and then ice is stored. Accordingly, since the supercooled water is discharged into water, a disturbance in water flow at the discharging port is reduced, resulting in that a clogged state in the pipe caused by occurrence and growth of ice at the discharging port can be eliminated.

Description

Detailed Description of the Invention

[0001]

[Industrial application] In recent years, the demand for electricity has increased sharply,
In summer, there is a significant imbalance between daytime and nighttime power demand due to cooling load. As a countermeasure against this, there is a cold heat storage method in which cold heat is stored by utilizing surplus power at night and is taken out in the daytime to be used for cooling to average power demand day and night.

[0002]

2. Description of the Related Art This cold heat storage system includes a cold water heat storage system and an ice heat storage system, but an ice heat storage system, which is more space-saving, has been attracting attention from the viewpoint of efficient use of equipment space.

Up to now, various ice making methods have been developed and proposed for the ice making system in the ice heat storage equipment. Ice making systems are roughly divided into two types, static method and dynamic method.Since the static method causes ice to grow on the heat transfer surface of the heat exchanger for ice making,
The heat transfer resistance increases as the ice thickness increases, and the ice making efficiency decreases. On the other hand, the dynamic method intermittently peels off ice deposited on the heat transfer surface of the ice making heat exchanger,
By producing supercooled water in the liquid phase below, the ice is not made to accrete on the heat transfer surface, so the ice making efficiency at the time of ice making is superior to that of the static method, and it was produced. Due to the small shape of the ice, it is possible to quickly follow the cooling load when performing cooling in the daytime using the ice that has accumulated heat at night.

Conventionally, various methods have been proposed as dynamic ice making methods. For example, a method of cooling a mixture of antifreeze liquid and water, or a shell-and-tube heat exchanger as disclosed in JP-A-1-114682 is used to measure the temperature of the heat transfer surface on the water side. A method of continuously producing supercooled water by controlling at 5,8 to 0 ° C. and making ice in a heat storage tank, and a water flow rate of 0.1 m / m as disclosed in JP-A No. 62-147271. Keep it for more than sec and continuously produce supercooled water to make ice.

Further, the present applicant has filed Japanese Patent Application No. 05-224238.
In this issue, in an ice making system that uses this supercooled water, excellent heat exchange performance, easy maintenance and inspection of heat transfer plates, high flexibility in capacity setting, and compact equipment configuration can be obtained. It proposes an ice making method using a plate heat exchanger, which has many advantages.

As shown in FIG. 2, the ice making method of this ice heat storage system uses a pump 11 for supplying a refrigerant (brine) 10 cooled by a refrigerator 9 operated by night power to a refrigerant passage of an ice making heat exchanger 3. The pump 7 supplies water 2a from the bottom of the heat storage tank 1 to the water flow path of the ice making heat exchanger 3 via the inlet side conduit 4, and the supercooled water cooled by the refrigerant is circulated on the outlet side. Nozzle 1 from the upper part of heat storage tank 1 through discharge pipe 5 into the heat storage tank
2 is configured to be discharged and dropped. In this way, the cold water in which the ice-making heat is stored in the night heat storage tank is used for cooling during the peak power load in the daytime. Cooling load 1 during the day
When the cold water stored in the heat storage tank 1 is supplied to the heat storage tank 3, the pump 14 is driven to supply the water 2 at the cooling water intake 15.
Is extracted and supplied to the cold water heat exchanger 16, and the heat storage tank 1
From the return water pipe nozzle 17 arranged at the upper part, the water is returned to the heat storage tank 1 in the form of spray. Cooling load 1
3 circulates between the cold water heat exchanger 16 and the cold water heat exchanger 16,
Is supplied to the cooling load 13 via the cold water heat exchanger 16 and the water 19.

[0007]

Conventionally, in order to make supercooled water in the dynamic method, the supercooled liquid water below 0 ° C. is discharged from the nozzle 12 of the discharge pipe 5 to the upper part of the heat storage tank 1 as described above. However, it is a general method to drop it on the water surface to change it into an ice phase. In addition to this, as means for changing the phase of supercooled water (liquid phase) to ice (solid phase), a method of dropping supercooled water on a baffle provided on the water surface of the heat storage tank and changing it to an ice phase, JP-A-64-90973
As disclosed in Japanese Patent Publication, supercooled water is supplied to the upstream side of a gutter to which a piezoelectric element is attached, and ultrasonic vibration is applied to the supercooled water flowing in the gutter to change it into an ice phase and ice and water. Various devices have been proposed, such as those that are supplied to the heat storage tank as a mixture of.

However, in all of these conventional techniques, the supercooled water discharged from the ice-making heat converter is discharged into the air from the discharge pipe and put into the heat storage tank, so that the water flow is likely to be disturbed at the outlet of the discharge pipe. This ice changes into an ice phase and grows at the outlet of the discharge pipe, and the supercooled water in the discharge pipe and in the water flow path of the heat exchanger also becomes ice and blocks the flow path, hindering ice making operation. I had to come.

An object of the present invention is to solve this problem and to smoothly perform the ice making operation in the ice heat storage system.

[0010]

In the present invention, in order to solve the above-mentioned problems, the discharge port of the discharge pipe 5 for discharging the supercooled water cooled to the supercooled state by the ice making heat exchanger 3 to the heat storage tank 1. 6 was installed in the water 2 in the heat storage tank 1.

[0011]

It is known that the supercooled water (liquid phase) has a turbulent flow or changes to ice (solid phase) in a stationary state. In the present invention, the outlet 6 of the discharge pipe 5 of the supercooled water is provided in the underwater 2 of the heat storage tank 1, so that the outlet 6 of the discharge pipe 5 is
The turbulence of the flow of supercooled water that occurs in the part is reduced to suppress the change to the ice phase.

That is, when the supercooled water is discharged into the air from the discharge pipe outlet 6 as in the conventional case, the flow of water surrounded by the inner surface of the discharge pipe and the water interface (solid-liquid interface) flows outward from the discharge pipe outlet. In that case, the water flow suddenly disperses because it has an interface between water and air, and the turbulence easily generated ice at the outlet of the discharge pipe.

In the present invention, since the supercooled water is discharged in the water 2 in the heat storage tank 1, the water 2a discharged from the outlet 6 of the discharge pipe moves while gradually mixing with the same kind of liquid. Therefore, the dispersion is gentle, no turbulence occurs, and the ice phase does not change at the outlet 6 of the discharge pipe. The supercooled water discharged from the discharge pipe has a gradual flow as it moves away from the outlet, and becomes ice near the wall surface of the heat storage tank, but since it has a specific gravity lighter than water, it rises upward and the heat storage tank 1
Floats near the water surface inside.

[0014]

FIG. 1 shows an embodiment of the present invention.
On the lower side wall of the heat storage tank 1, an inlet side pipeline 4 of an ice making heat exchanger 3 which is mainly operated by night power is provided, and a circulation pump 7 is installed in the middle of the inlet side pipeline 4. . The outlet side of the ice making heat exchanger 3 is connected to a discharge pipe 5 for sending the cooling water cooled by the ice making heat exchanger 3 to the heat storage tank 1, and the outlet 6 of the discharge pipe 5 is connected to the water 2 in the heat storage tank 1. The water 2a in the heat storage tank 3 is arranged so as to be circulated in the heat storage tank 1 from the inlet side pipe line 4 to the ice making heat exchanger 3 by the circulation pump 4 and the discharge pipe 5 into the heat storage tank 1. Has been

In the ice making heat exchanger 3, the water 2 in the heat storage tank 1
The cooling medium for cooling a, the refrigerator, the equipment on the load side, and the equipment are the same as those of the conventional example (FIG. 2), and are not shown. In the embodiment (FIG. 1) of the present invention, the outlet 6 of the discharge pipe 5 may be any of the bottom portion, the intermediate portion, and the upper portion as long as it is the water 2 in the heat storage tank 1 unless it is in the vicinity of the inlet side pipe 4. The number of outlets of the discharge pipe 5 may be one or more, but it is preferable to dispose the discharge pipe 5 as far as possible from the connection port of the inlet side pipe 4. This is because it is effective in cooling the water 2a in the heat storage tank 1 as a whole.

When the ice making operation is performed with the above-mentioned structure,
The water 2a in the heat storage tank 1 is sent from the inlet side pipe 4 to the ice making heat exchanger 3 by the circulation pump 7, is cooled, is discharged from the outlet 6 of the discharge pipe 5 into the water 2 in the heat storage tank 1, is circulated, and is gradually cooled. As a result, a supercooled state of 0 ° C. or less is reached. When the supercooled state is reached, when the supercooled water discharged from the outlet 6 of the discharge pipe 5 is discharged into the water 2 in the heat storage tank 1, the flow is not disturbed at the outlet, so that it changes into an ice phase. Instead, the water becomes ice 8 near the wall surface or in the water away from the outlet 6, and floats near the water surface of the heat storage tank, and the proportion of the ice 8 stored in the heat storage tank 1 increases as the ice 8 is repeated. The ice 8 thus stored in the heat storage tank 1 is consumed in the daytime cooling operation to become water, and is iced again in the nighttime ice making operation to be used as an ice heat storage system.

The ice making heat exchanger 3 used in the present invention may be of any type such as shell & tube type or plate type.

[0018]

According to the present invention, the discharge port of the discharge pipe is installed in the water of the heat storage tank, so that when supercooled water is discharged from the discharge pipe, generation of ice occurring at the discharge port is suppressed. Therefore, the discharge pipe can be prevented from being blocked by ice, and the ice storage operation in the ice heat storage system can be smoothly performed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2 is a block diagram showing an overall configuration of a conventional ice heat storage system.

[Explanation of symbols]

 1: heat storage tank 2: water 3: ice making heat exchanger 4: inlet side pipe 5: discharge pipe 6: outlet (discharge port) 7: circulation pump 8: ice

Claims (1)

[Claims] 1. A supercooling device, characterized in that the outlet of a discharge pipe for discharging supercooled water cooled to a supercooled state by an ice making heat exchanger to a heat storage tank is installed in water in the heat storage tank. Discharge method of supercooled water in ice making system.