JP2862946B2 - Heat storage type air conditioning cooling method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a regenerative air conditioning / cooling method using a steel pipe pile as a heat storage tank.

[Prior Art] The balance between the demand and supply of power has a great difference between daytime and nighttime. In particular, this difference is remarkable in summer when air conditioning is used. Therefore, electric power companies are working to spread a heat storage system that stores energy required for cooling at night and uses the energy for cooling during the day. Electric power companies are conducting R & D on thermal storage systems.

As a conventional heat storage system, a water heat storage system using a temperature difference of water is mainly used. However, the water heat storage system has a problem in that a huge heat storage tank for storing water is required.

On the other hand, in recent years, an ice heat storage system using latent heat of melting of ice has been used. The heat storage tank used for the ice heat storage system is about 1/10 the volume of the water storage tank for water heat storage, and is very small. Therefore, the ice heat storage system is becoming mainstream instead of the water heat storage system because it can be applied to a small space.

Ice heat storage systems can be broadly classified into a static type (ice-on-coil type) and a dynamic type (liquid ice type). In the static type, a refrigerant (generally, chlorofluorocarbon or brine) from a refrigerator is caused to flow through an ice-making tube installed in a heat storage tank to grow ice on the surface of the tube. A typical static type system is a direct expansion type in which the refrigerant of a refrigerator is directly flowed into an ice-making tube, and ice is formed on the surface of the ice-making tube. There are a brine type, a heat pipe type, and the like for making ice in the same manner as the direct expansion type.

On the other hand, in the dynamic type, ice is separately made by an ice making device and stored in a heat storage tank. A typical dynamic type system is a sherbet type ice made by an ice making device and stored in a heat storage tank, or a thin plate of ice is grown on an ice making plate and crushed into ice chips to store heat. There are a harvest type that stores in a tank, a method that cools brine with low concentration, and turns water in the brine into particulate ice.

[Problems to be Solved by the Invention] However, in the static type, since the ice making tube is installed in the heat storage tank, it is necessary to match the shape of the ice making tube to the heat storage tank. For this reason, the ice-making tube has a shape of a coil wound in the direction of the upper layer from the bottom of the heat storage tank, or a shape in which a plurality of straight pipes are arranged in the vertical direction of the heat storage tank. Become something. When an ice-making tube having such a shape is used, the refrigerant supplied to the ice-making tube vigorously grows ice near the refrigerant supply port of the ice-making tube. However, the temperature of the refrigerant increases as it flows through the ice-making tube. For this reason, ice does not grow near the refrigerant discharge port of the ice making tube than near the refrigerant supply port. Therefore, ice is not obtained uniformly over the entire length of the ice making tube. As a result, the following problem occurs during melting of ice, that is, during cooling operation.

Usually, in the cooling operation, first, water in an unfrozen portion of the heat storage tank is taken out by a pump. The cold heat of this water is consumed on the load side. Next, the water deprived of cold is returned to the heat storage tank again. Next, the ice of the temperature rise of the water returned to the heat storage tank is melted. Therefore, if ice is not obtained uniformly over the entire length of the ice making tube,
Ice grows remarkably near the coolant supply port of the ice making tube. This ice becomes an ice block. The ice block has a small surface area in contact with water in the heat storage tank. For this reason, ice blocks are not sufficiently melted.
As a result, sufficient cold heat required on the load side cannot be supplied. Further, when a plurality of ice making tubes are arranged in the heat storage tank, the ice grown in the ice making tubes is connected to each other. In ice heat storage, the connection of the ice pieces is called bridging. In the case of a coil-shaped ice making tube, bridging occurs above and below the coil. The bridging is a major obstacle during the cooling operation, and adversely affects not only the cooling operation but also the performance of the refrigerator when growing ice in the ice making tube.

In the dynamic type, since the ice-making tube is not provided in the heat storage tank, there is no need to worry about bridging in the ice-making tube. In this system, ice is made in each ice making process. This ice is transported to a heat storage tank using a transport means such as a pump or a conveyor, and is stored therein. The form of the ice carried to the heat storage tank is in the form of ice pieces or particles. This ice floats on the surface of the heat storage tank. Therefore, when the floating area of the ice in the heat storage tank is small, the ice carried to the heat storage tank collects in one place. As a result, ice chips or granular ice are compacted by buoyancy to form an ice block as in the static type. For this reason, when storing ice made in the heat storage tank, it is necessary to make the shape of the heat storage tank wider to some extent in a plane.

Ice heat storage systems, compared to conventional water heat storage systems,
The capacity of the heat storage tank can be greatly reduced to 1/10. As a result, in the ice heat storage system, the heat storage tank can be installed on the roof. Then, it is not necessary to construct a heat storage tank under the double slab on the basement of the building of the water heat storage system. Building a heat storage tank under the double slab on the basement floor of the building is rare because there are few buildings with space for installing a huge heat storage tank other than under the double slab, and the cost of building a dedicated heat storage tank is low. It is because it becomes high.

However, even if the volume of the thermal storage tank of the ice thermal storage system is reduced to one tenth, the thermal storage tank capable of air-conditioning the entire building becomes considerably large. For this reason, this heat storage tank cannot be neglected in terms of the building structure. Therefore, the construction cost of the building becomes high considering the weight of the heat storage tank. In addition to this,
Recent buildings utilize a small site area effectively, so the height of the building is increasing, and some buildings cannot be opened and closed. Therefore, it is more important to adjust the indoor environment by using an air conditioner. However, the space for installing air conditioning equipment is
It is necessary to minimize it to secure a living area. Thus, there is still a strong need for an ice heat storage system to be a vertical ice heat storage system that can be made as small as possible.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a regenerative air conditioning / cooling method using a vertical ice thermal storage system that is high-performance, can be miniaturized, and is inexpensive.

[Means for Solving the Problems] The present invention provides a refrigeration circuit that performs cooling by circulating a refrigerant and repeatedly repeating condensation and vaporization, and heat exchange of refrigeration heat of the refrigeration circuit with chilled water flowing through a chilled water circulation path. In a method of performing air conditioning and cooling through a load type air conditioning circuit using cold water, the refrigeration circuit is formed by a long heat pipe, and the heat pipe is accommodated in a long steel pipe pile heat storage tank, and the heat pipe is A cold heat source section surrounding the heat radiating section is provided, a refrigerant is circulated through the cold heat source section, and then ice is made by a cooling action of the refrigerant around the heat pipe heat radiating section, and then cold water flowing through the cold water circulation path is provided. , And returning the cold water to a load-type air conditioning circuit.

[Operation] In the regenerative air conditioning / cooling method of the present invention, a steel pipe pile is used as a heat storage tank. Therefore, space for the heat storage tank is unnecessary. The soil around the steel pipe pile acts as a heat storage material having a large heat capacity. Accordingly, during the ice making operation, the water in the heat storage tank is cooled by the heat pipe, and the soil is also cooled at the same time. As a result, when all the ice melts in the air conditioning operation, the sufficiently cooled soil acts as a cold heat source, lowers the water temperature inside the steel pipe pile, and contributes to cooling air conditioning.

Further, in the regenerative air conditioning and cooling method of the present invention, a sufficiently long heat pipe is used as an ice making tube. The heat exchange of the heat pipe is performed by utilizing the latent heat of evaporation and condensation of the working fluid.
For this reason, the surface temperature of the entire heat pipe becomes substantially close to the steam temperature of the working fluid inside. In other words, the heat radiation portion is made sufficiently long to obtain an ice layer having a uniform thickness substantially over substantially the entire length of the heat pipe. As a result, excessive icing in the steel pipe pile can be prevented, a sufficient amount of icing can be secured, and daytime air conditioning operation can be performed efficiently.

EXAMPLES Hereinafter, one example of the present invention will be specifically described with reference to the drawings.

FIG. 1 is an explanatory diagram showing a system for cooling a building of four floors above ground and one floor below ground by applying the present invention. 1 in the figure
It is a building. On the ground surface outside the building 1, a refrigeration system 2
Is installed. The refrigerating device 2 includes a compressor 3 and a condenser 4
It is composed of A plurality of long steel pipe piles are attached to the bottom of the building 1. The steel pipe pile serves as a heat storage layer as well as a building foundation member (hereinafter, referred to as a steel pipe pile heat storage tank 5). The steel pipe pile heat storage tank 5 is buried deep underground. Moreover, in each steel pipe pile thermal storage tank 5,
Included is a significantly longer heat pump 6 and an evaporator 7 mounted on the upper end of the heat pump 6. A first refrigerant pipe 8 is attached to the compressor 3. Condenser 4
Is provided with a second refrigerant pipe 9. Each of the refrigerant pipes 8 and 9 branches and extends to each of the steel pipe pile heat storage tanks 5, and is connected to the evaporator 7 in each of the steel pipe pile heat storage tanks 5. Also, the refrigerating device 2, the evaporator 7,
The first refrigerant pipe 8 and the second refrigerant pipe 9 constitute a refrigeration circuit.

On the other hand, an air conditioner 10 is installed on each floor. Each air conditioner 10 is provided with a first air conditioning pipe 11 and a second air conditioning pipe 12. Each first air conditioning pipe 11 is connected to a first air conditioning pipe main pipe 13. First air conditioning pipe main pipe 13
Is further branched and extended into each steel pipe pile heat storage tank 5. That is, the first main air-conditioning pipe main pipe 13 and the inside of each steel pipe pile heat storage tank 5 are communicated by the first branch air-conditioning pipe 20. Similarly to the first air-conditioning pipe 11, each of the second air-conditioning pipes 12 is extended to the inside of each steel pipe pile heat storage tank 5 by the second branch air-conditioning pipe 21 via the second air-conditioning pipe main pipe 14. . Further, a chilled water pump 15 is attached to the first air conditioning piping main pipe 13. Air conditioner 10, Steel pipe pile thermal storage tank 5, First
The air-conditioning pipe 11, the first air-conditioning pipe main pipe 13, the first branch air-conditioning pipe 20, the chilled water pump 15, the second air-conditioning pipe 12, the second air-conditioning pipe main pipe 14, and the second branch air-conditioning pipe 21 Type air conditioning circuit.

FIG. 2 is an explanatory view of a main part of the steel pipe pile heat storage tank 5 used in the present invention. Inside the steel pipe pile heat storage tank 5, a heat pipe 6 and an evaporator 7 acting as a cold heat source unit attached to the upper end of the heat pipe 6 are included. Also,
Water 16 is stored inside the steel pipe pile heat storage tank 5. Ice 17 having a predetermined thickness is deposited on the surfaces of the heat pipe 6 and the evaporator 7. A first refrigerant pipe 8 is connected to the top of the evaporator 7. A second refrigerant pipe 9 is connected to a lower part of the evaporator 7. A first branch air-conditioning pipe 20 is inserted into the steel pipe pile heat storage tank 5. First
The branch air-conditioning pipe 20 extends to near the bottom of the steel pipe pile heat storage tank 5. A second branch air-conditioning pipe 21 is also inserted into the steel pipe pile heat storage tank 5. The second branch air-conditioning pipe 21
It extends to the vicinity of the evaporator 7.

FIG. 3 is an explanatory diagram of the heat pipe 6 used in the present invention. The heat pipe 6 is a small amount of hydraulic fluid serving as a heat medium.
19 is housed inside a container 18 and both ends thereof are sealed. In addition, a wick exhibiting a capillary phenomenon is provided inside the container 18.

The operation of the heat pipe is performed as follows. First, one end of the heat pipe is heated to evaporate the working fluid inside. At this time, the working fluid is directed to the other end having a relatively low pressure, and a steam flow is generated. The vapor stream contacts the inner wall of the other end of the heat pipe, releases latent heat and condenses. The condensed working fluid returns along the inner wall of the tube to the evaporation portion.
The heat pipe performs heat transfer by repeating such an operation. For this reason, a transport device such as a pump can be eliminated.

With the regenerative air conditioning cooling system configured as described above, cooling is performed as follows.

This system includes a refrigeration circuit having a refrigeration device for growing ice on the surface of a heat pipe, and a load-type air-conditioning circuit for utilizing the cold heat of ice in a steel pipe pile heat storage tank.

First, an inexpensive electric power generally called late-night electric power is used to operate a night-time refrigeration circuit, and perform an ice-making operation in which ice required for cooling in a day is grown and stored on the surface of a heat pipe of a steel pipe pile heat storage tank. The ice making operation is performed for 10 hours from 22:00 at night to 8:00 in the next morning when electric power is supplied from the power company at midnight.

First, the ice making of the heat pipe is performed by the compressor 3
The refrigerant that has passed through the condenser 4 (hereinafter, abbreviated as frozen refrigerant) is sent to the evaporator 7. At this time, the frozen refrigerant is
As shown in the figure, the gas is supplied to the lower part of the evaporator 7 in the steel pipe pile heat storage tank 5 through the second refrigerant pipe 9. Thereby, the upper end of the heat pipe 6 is cooled by the heat of vaporization of the frozen refrigerant.

When the upper end of the heat pipe 6 is cooled, the water 16 in the steel pipe pile heat storage tank 5 becomes a heat source of the heat pipe 6 as shown in FIG. For this reason, the working wave 19 in the container 18 evaporates and becomes an upward steam flow. This vapor flow contacts the wall surface of the container 18 to release latent heat, is condensed again, and returns to the lower part. The released latent heat actively moves to the evaporator 7 cooled by the refrigerant. Therefore, the water 16 is deprived of heat and eventually becomes 0 ° C. This allows the water 16 to
It becomes ice 17 and lands on the surface of the heat pipe 6. In this manner, an ice layer having a uniform thickness is grown over substantially the entire length of the heat pipe 6.

On the other hand, the refrigerant vaporized in the evaporator 7 is supplied to the compressor 3 of the refrigeration apparatus 2 through the first refrigerant pipe 8 as shown in FIG. Thereafter, the refrigerant is introduced into the condenser 4 and radiates the absorbed heat to become a frozen refrigerant.

In this way, the refrigeration circuit is operated until 8:00 in the morning when the supply of power at midnight ends, and required ice grows on the surface of the heat pipe to store cold heat.

Next, from 8:00 in the morning when the ice making operation is completed, the load type air conditioning circuit is operated to perform the cooling operation. First, by operating the chilled water pump 15, the first branch air conditioning pipe 20, the first air conditioning pipe main pipe 13, the first air conditioning pipe 11, the air conditioner 10, the air conditioner 10,
The water in the second air conditioning pipe 12, the second main air conditioning pipe 14, the second branch air conditioning pipe 21, and the steel pipe pile heat storage tank 5 circulates.
By this circulation, the circulating water absorbs the cooling load from the air conditioner 10. Circulating water heated by cooling load (for example, 12
2) flows into the vicinity of the upper part of the steel pipe pile heat storage tank 5 through the second branch air-conditioning pipe 21 as shown in FIG. The circulating water is cooled by melting the ice grown on the surface of the heat pipe 6 (for example, 4 to 7 ° C.). The cooled circulating water is sent to the air conditioner 10 again through the first branch air conditioning pipe 20. In this way, the indoor environment of the building is kept in a good air-conditioning state. This cooling operation can be continued until 22:00 at night when the ice making operation starts. In the meantime, if all the ice 17 in the steel pipe pile heat storage tank 5 is consumed and a larger air conditioning load occurs, the refrigeration circuit is operated again,
Backup operation can be performed.

In this way, the ice making operation at night and the cooling operation at daytime can be favorably performed.

In addition, it is not necessary to insulate the heat storage tank, which is indispensable in the conventional heat storage system, and the construction cost can be reduced.

[Effects of the Invention] As described above, the regenerative air conditioning / cooling method of the present invention includes:
Since the steel pipe pile can also be used as a heat storage tank, the space for the heat storage tank can be saved. Further, since the most stable cold water of about 4 ° C. can be taken out by directly melting the ice for a long time, the amount of water supplied to the air conditioner can be reduced, and energy can be saved. Further, in the regenerative air conditioning / cooling method of the present invention, heat loss in the regenerator can be prevented.

As described above, the regenerative air conditioning / cooling method of the present invention can use downsized equipment and can reduce initial costs and running costs.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a system for cooling a building of 4 floors above ground and 1 floor below ground by applying the present invention, and FIG. 2 is an explanatory view of a main part of a steel pipe pile heat storage tank used in the method according to the present invention. , Third
The figure is an explanatory view of a heat pipe used in the present invention. DESCRIPTION OF SYMBOLS 1 ... Building, 2 ... Refrigeration apparatus, 3 ... Compressor, 4 ... Condenser, 5 ... Steel pipe pile heat storage tank, 6 ... Heat pipe, 7 ...
... evaporator, 8 ... first refrigerant pipe, 9 ... second refrigerant pipe, 10 ... air conditioner, 11 ... first air conditioning pipe, 12 ... second
Air-conditioning pipes, 13 ... first air-conditioning pipe main pipe, 14 ... second air-conditioning pipe main pipe, 15 ... cold water pump, 16 ... water, 17 ...
Ice, 18 ... container, 19 ... hydraulic fluid, 20 ... first branch air-conditioning pipe, 21 ... second branch air-conditioning pipe.

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shiro Kawakami 3-7-24 Kuragakiuchi, Ibaraki-shi, Osaka (72) Inventor Kozo 1-7-8 Oyodominami, Kita-ku, Osaka-shi, Osaka 705 (56) References JP-A-1-114639 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F24F 5/00

Claims (1)

(57) [Claims] 1. A refrigeration circuit for cooling by circulating a refrigerant to repeatedly condense and vaporize, and exchanges heat of the refrigeration circuit with chilled water flowing through a chilled water circulation path, and the chilled water is used for the cooling through a load type air conditioning circuit. In the method for performing air conditioning and cooling, the refrigeration circuit is formed by a long heat pipe, the heat pipe is housed in a long steel pipe pile heat storage tank, and a heat source for surrounding a heat radiating portion of the heat pipe. Section, a refrigerant is circulated through the cold heat source section, then ice making is performed by the cooling action of the refrigerant around the heat pipe heat radiating section, and then the cold water flowing through the cold water circulation path is cooled, and then the cold water is cooled. A heat storage type air conditioning and cooling method, wherein the air is returned to a load type air conditioning circuit.