JPH086945B2 - Supercooled water production equipment for ice heat storage equipment for air conditioning - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing supercooled water in ice heat storage equipment for air conditioning.

[0002]

2. Description of the Related Art When cooling and heating water is circulated through a water side heat exchanger of a fan coil unit or a water heat source heat pump unit installed in a building to cool and heat the cold heat during cooling, ice forms in a heat storage tank. The so-called ice heat storage method, which stores the energy in, is drawing attention, and some have come into operation. This is because, for example, the refrigerator is driven by night-time power to make ice, and a large amount of cold heat is stored in the heat storage tank in the ice state, and during the cooling operation, the cold heat of the ice is taken out as cold water to the secondary heat exchanger. Since it circulates and uses latent heat of water, a large amount of cold heat can be stored even in a small-scale device.

In this ice heat storage method, there are two types of ice to be stored depending on the difference in the ice making method: ice blocks (solid) and sherbet (liquid or slurry in which fine ice and water are mixed). Be divided. Both have their advantages and disadvantages, but in the ice lump method, when the ice lump is generated in the heat storage water tank (generated on the surface of the heat exchanger), if the ice layer becomes thicker, the heat conduction will decrease accordingly, so make it a large thickness. There is a limit to this, so the ice fill factor (I.
PF) is only around 10%, and it is inevitable that the heat storage efficiency will deteriorate. Although it has been reported that a special solution containing an additive is used to improve the IPF and the heat storage water tank itself is configured as a pressure vessel, the heat storage type water heat source cooling and heating equipment of an existing building is used as it is for ice heat storage. There are many problems when applied to the method.

On the other hand, when making sherbet-like ice, the IPF can be made very large, but to make a large amount of water into sherbet-like ice generally requires a very large-scale facility. Regarding this sherbet-like heat storage method, for example, JP-A-63-123968-9 and JP-A-63-1
Those described in the publications 29274-5 are known. Further, Japanese Patent Application Laid-Open Nos. 63-217171 and 6 related to the same applicant
3-231157 proposes a method and an apparatus for making fine ice from supercooled water, and on the condition that the supercooled water is continuously manufactured by a heat transfer tube, the improvement thereof is required.
JP 63-271074, JP 64-75869, JP 64-90973, JP 1-114682, JP 63-1
No. 39459, No. 1-88235, No. 1-88236, No. 1-88237, No. 1-97135, No. 1-112345, No. 1-120022 Bulletin, Actual Kaihei 1-
No. 125940, No. 1-136832, No. 1-48538
Various proposals have been made to the official gazette, the utility model 1-178528, the utility model 2-527, etc.

In any case, the subcooler of the ice making system for producing sherbet-like ice from the supercooled water proposed in these cases has a heat transfer tube through which water is passed in a cooling container. The brine of the refrigerator is passed through as a cooling medium in the cooling container, or the cooling container is configured to function as an evaporator of the heat pump device. As a result, the inner wall temperature of the heat transfer tube is below 0 ° C,
If the temperature is maintained at 5.8 ° C or higher, a continuous flow of supercooled water can be produced without freezing in the pipe regardless of changes in the inlet temperature and flow rate of water.

[0006]

In the above-mentioned supercooler for continuously producing supercooled water with a heat transfer tube, the heat exchange is performed by water passing through the tube and brine outside the tube (brine cooling system) or a gas refrigerant ( This is heat exchange by heat transfer through the tube wall with the evaporator system of the heat pump). In other words, either heat transfer is convective heat transfer of liquid or gas phase fluid. Therefore,
There is a limit to improvement in terms of heat transfer coefficient and uniform heat transfer.

In order to overcome this limitation, Japanese Patent Application No. 2-37200 by the same applicant proposed that the subcooler be a full-liquid type evaporator. That is, when the shell of a shell-and-tube heat exchanger is used as an evaporator, the shell is filled with a liquid refrigerant sufficient to cover the tube through which water passes, and this liquid refrigerant is applied to the surface of the heat transfer tube. It is boiled and evaporated. According to this, heat transfer in the subcooler becomes boiling transfer, the heat transfer coefficient is improved, and uniform heat transfer is performed.

The present invention is intended to further improve the invention proposed in Japanese Patent Application No. 2-37200.

[0009]

According to the present invention, the air-conditioning heat source water stored in the heat storage tank is continuously supplied to the evaporator of the heat pump device to cool it to supercooled water of 0 ° C or lower,
Discharging this supercooled water from the evaporator as a continuous flow,
In an ice storage facility for air conditioning for supplying this discharge flow to the heat storage tank while releasing the supercooled state to store ice-water slurry in the heat storage tank, the evaporator of the heat pump device has its tube side. Is composed of a shell-and-tube type heat exchanger in which the heat source water is continuously supplied to the shell and the refrigerant of the heat pump is supplied to the shell side, and the heat pump device is the evaporator → receiver → compressor → condenser -> Expansion valve-> the receiver-> the evaporator is constituted by a refrigerant circuit in order, a pump is installed in the pipe line from the receiver to the evaporator, and the refrigerant evaporation amount in the evaporator Provided is a supercooled water producing device in an ice storage facility for air conditioning, characterized in that a large amount of liquid refrigerant is sent from the liquid receiver into the evaporator by means of this pump.

That is, the return refrigerant from the full-fill type evaporator is received by the receiver and returned to the compressor, and the refrigerant on the outlet side of the condenser is introduced into the receiver through an expansion valve. The liquid refrigerant separated into gas and liquid in the receiver is forcibly sent to the evaporator by a pump.

[Operation] With this configuration, the liquid refrigerant can be sent into the evaporator several times as much as the amount of evaporation, so that the heat transfer coefficient is further improved as compared with the system of Japanese Patent Application No. 2-37200.
In addition, uniform heat transfer can be performed. By using the pump, the capacity and type (vertical type or horizontal type) of the refrigerant liquid filling type evaporator can be freely designed, and the liquid refrigerant can be divided and supplied to a plurality of evaporators.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the device of the present invention. Reference numeral 1 is a heat storage tank, 2 is a subcooler, and 3 is a circulation pump. The water in the heat storage tank 1 is continuously supplied to the subcooler 2 through a water channel 4 by the drive of the pump 3, and the subcooler 2 causes zero degrees. The supercooled water 5 below ℃ is discharged into the atmosphere, and the discharged flow of the supercooled water 5 collides with the supercooled state releasing device 6 and is returned to the heat storage tank 1. When the supercooled state is released, it becomes fine ice, and shear-bed-shaped ice 7 accumulates in the heat storage tank 1.

Although not shown, the water (cold water) coexisting with the ice 7 is circulated to a water side heat exchanger of a fan coil unit or a heat pump unit arranged in the building, and heat source water for air conditioning ( It is supplied to the cold heat source) and returned to the heat storage tank 1 again. It is possible to operate the supercooled water production device (heat source device operation) and the air conditioning operation (load side operation) at the same time. By using the cheap nighttime electricity, the former accumulates heat at night. May be used for air conditioning during the day. In the heating operation, the supercooled water production device is stopped, hot water is stored in the heat storage tank 1 by a heat source device (not shown) such as a boiler or a heat pump device, and the hot water is supplied to the load side.

The subcooler 2 comprises a shell-and-tube heat exchanger in which a large number of heat transfer tubes (tubes) 9 are arranged in a shell 10. Each tube 9 (hereinafter referred to as a heat transfer tube 9) is arranged so as to penetrate through a shell 10 (hereinafter referred to as a cooling vessel 10), one end of which is open to an inlet header portion 11 and the other end is exposed to the atmosphere. Since it is open, the water introduced into the water inlet header portion 11 flows through each heat transfer tube 9 and is discharged into the atmosphere from the other opening end. In the illustrated example, a vertical shell-and-tube heat exchanger in which the heat transfer tubes 9 are vertically aligned is used, but a horizontal heat exchanger may be used.

The shell-side cooling container 10 functions as an evaporator of a heat pump device, and this is a liquid-filled evaporator. That is, while the heat pump device is operating, the liquid refrigerant exists in the cooling container 10 so as to immerse the heat transfer tube 9. The liquid transfer tube 9 heats this liquid refrigerant and is sucked by the drive of the compressor as described later. As a result, the liquid is put in a state of boiling.

In the present invention, this heat pump device includes an evaporator (that is, a cooling container 10), a liquid receiver 13, a compressor 14,
It consists of a refrigerant circuit that goes through a condenser 15, an expansion valve 16, a liquid receiver 13, and an evaporator 10 in that order. A pump 17 is installed in the conduit from the liquid receiver 13 to the evaporator 10, and inside the evaporator 10. This pump 17 is characterized in that a larger amount of liquid refrigerant than the refrigerant evaporation amount is sent from the liquid receiver 13 to the evaporator 10.
That is, a liquid receiver 13 having a gas-liquid separation function is arranged across the refrigerant pipe line from the expansion valve 16 to the evaporator 10 and the refrigerant pipe line from the evaporator 10 to the compressor 14, A pump 17 for sending a liquid refrigerant from the liquid container 13 to the evaporator 10 is provided.

The liquid receiver 13 is a cylindrical container made of a heat insulating material and is installed vertically. A liquid reservoir 18 is provided in the lower part thereof, and a liquid pipe 19 leading from the liquid reservoir 18 to the evaporator 10 is installed, and a pump 17 is interposed in the liquid pipe 19. Further, an eliminator 20 (droplet collector) is attached to the upper inside of the liquid receiver 13, and a gas pipe 21 communicating with the compressor 14 from a position above the eliminator 20 is installed. Further, in the illustrated example, a refrigerant inlet 22 passing through the expansion valve 16 is provided below the liquid receiver 13, and a refrigerant inlet 23 from the evaporator 10 is provided above the liquid receiver 13 (below the eliminator 20). ing.

During operation of the heat pump device, liquid level control is performed in the liquid receiver 13 so that the liquid level 24 of the refrigerant liquid falls within a predetermined range. This is done so that the liquid level detected by the liquid level detector 25 falls within the set range.
It is performed by adjusting the opening degree of.

In the evaporator 10, the liquid refrigerant pumped from the pump 17 is received from the inlet 26 at the lower part of the evaporator 10, and the heat is transferred from the heat transfer tube 9 to boil while the inside of the evaporator 10 is rising. Then, it is sent as a gas-liquid mixed fluid from the upper outlet 27 to the liquid receiver 13. On the other hand, as the condenser 15, a liquid-to-liquid heat exchanger or a liquid-to-air heat exchanger is used, and the high-pressure refrigerant discharged from the compressor 14 radiates heat to cold water or ventilation to be liquefied here.

As described above, according to the device of the present invention,
By controlling the opening degree of the expansion valve 16, a predetermined liquid level is set in the receiver 13.
Refrigerant liquid is stored while maintaining 24, and this refrigerant liquid is pumped.
As a result of forced liquid transfer into the evaporator 10 by the 17,
The inside is filled with the liquid refrigerant. The liquid refrigerant introduced into the evaporator 10 receives heat from the heat transfer tube 9 and boils, but the gas-liquid mixed fluid is separated into gas and liquid by the liquid receiver 13, and the vaporized portion is compressed by the compressor 14
It is sucked into and the liquid is collected in the liquid reservoir 18. Therefore, the normal refrigerant circulation amount by the compressor 14 is secured, and the refrigerant liquid is repeatedly circulated in the receiver 13 → pump 17 → evaporator 10 → receiver 13 on the downstream side of the expansion valve 16, Circulating power will be applied by the pump 17.

This liquid receiver 13 → pump 17 → evaporator 10
→ The liquid circulation of the liquid receiver 13 is not limited to the case where the number of the evaporators 10 is one as in the illustrated embodiment, and the liquid is circulated by dividing into a plurality of evaporators (that is, a plurality of subcoolers). You can also That is, the evaporator 10 is divided into a plurality of units, and the liquid receiver 1
3-> pump 17-> multiple evaporators 10-> liquid circulation of receiver 13
Cool between each evaporator and one receiver to create a ring.
By forming a medium path, supercooled water can be produced at multiple locations.
It In this case, multiple pumps 17 are also installed for each evaporator.
It is good to If supercooled water can be produced with multiple evaporators,
Even if the heat storage tank 1 has a large plane area, the entire tank
It becomes possible to store ice in the body on average, and a small aquarium
If there is a heat storage water tank divided into
You can also distribute the ice on. And somehow
Even if one evaporator has a freezing trouble for some reason,
The ice making operation can be continued without stopping the operation.
It is sufficient to thaw the frozen evaporator and restart it.
It is possible to minimize the decrease in operating efficiency due to
Become. In any case, the surface temperature of the heat transfer tube 9 must be maintained at 0 ° C. or lower and −5.8 ° C. or higher. If the surface temperature of the inner surface of the heat transfer tube 9 exceeds 0 ° C, supercooled water cannot be produced, and at temperatures lower than -5.8 ° C, the water inside the tube may freeze. If the inner surface temperature of the heat transfer tube 9 is in the range of −5.8 to 0 ° C., supercooled water can be continuously produced regardless of the amount of water supplied to the heat transfer tube 9 and the water temperature.

[0022]

According to the present invention, when supercooled water is produced and then sheerbed-like ice is produced to store ice heat for air-conditioning, the subcooler, which is the central equipment thereof, is provided with the boiling heat transfer system. Since it is configured as a liquid evaporator, the heat transfer coefficient is improved and uniform heat transfer is achieved throughout the heat transfer tube compared to the conventional convection heat transfer method. Moreover, since the supply of the liquid refrigerant into the evaporator is forcibly sent by the pump power in addition to the compressor power, the liquid refrigerant is sent by several times the refrigerant evaporation amount in the evaporator. Therefore, the heat transfer coefficient is further improved, uniform heat transfer can be achieved, and the temperature inside the heat transfer tube can be controlled accurately. In addition, the degree of freedom in designing the subcooler is increased, and the problem of continuously producing subcooled water below 0 ° C without freezing trouble becomes more flexible in terms of operation and design, resulting in high efficiency. Since the ice-making operation can be performed accurately with and, it can make a great contribution as an air-conditioning system using the ice heat storage method.

[Brief description of drawings]

FIG. 1 is an equipment layout diagram showing an overall configuration of a supercooled water production device for an ice heat storage facility for air conditioning according to the present invention.

[Explanation of symbols]

 1 Heat Storage Tank 2 Supercooler 5 Supercooled Water 6 Supercooled State Release Device 9 Heat Transfer Tube 10 Cooling Container (Evaporator Shell) 13 Liquid Receiver 14 Compressor 15 Condenser 16 Expansion Valve 17 Liquid Refrigerant Liquid Delivery Pump 18 Liquid Distillation 20 Eliminator 25 Liquid level detector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuru Moriya 3-7-25 Sagamigaoka, Zama, Kanagawa Prefecture Sunlight Hills 203 (72) Masayuki Yano 2-8-21-101, Kyowa, Sagamihara, Kanagawa

Claims (4)

[Claims] 1. A heat source water for air conditioning stored in a heat storage tank is continuously supplied to an evaporator of a heat pump device to cool it to supercooled water of 0 ° C. or less, and the supercooled water continuously flows from the evaporator. In the ice heat storage equipment for air conditioning, wherein the discharge flow is supplied to the heat storage tank while releasing the supercooled state and the ice-water slurry is stored in the heat storage tank, the evaporator of the heat pump device is , Which consists of a shell-and-tube type heat exchanger in which the heat source water is continuously passed to the tube side and the refrigerant of the heat pump is supplied to the shell side, and the heat pump device is the evaporator → receiver → compression A condenser circuit, an expansion valve, a receiver, and an evaporator, and a refrigerant circuit that passes through the evaporator. A pump is installed in a pipe line from the receiver to the evaporator, and the refrigerant in the evaporator is provided. Use a larger amount of liquid refrigerant than the amount of evaporation. The subcooling water producing apparatus in the ice heat storage facility for air conditioning, wherein the pump is used to transfer the liquid from the inside of the receiver to the inside of the evaporator. 2. The liquid receiver is provided with a liquid level gauge, and the opening of the expansion valve is controlled according to the detection value of the liquid level gauge so that the liquid level in the liquid receiver falls within a set range. The supercooled water production apparatus described in 1. 3. The inner temperature of the tube of the evaporator is −5.8 ° C.
The supercooled water production apparatus according to claim 1 or 2, which is maintained at 0 ° C or lower. 4. The evaporator is divided into a plurality of units, and each evaporator is
A refrigerant path is formed between one of the liquid receivers.
The supercooled water production apparatus according to 2 or 3 .