JPH03294730A - Heat accumulation type air-conditioning and cooling method - Google Patents

Abstract

PURPOSE:To obtain a heat accumulation type air-conditioning and cooling method which allows an apparatus with a high performance to be sized down and produced at a low cost, by a method wherein ice making is carried out by the cooling action of a refrigerant around the heat releasing part of a heat pipe, and the cold water that flows along a cold water circulation path is returned to a load side air-conditioning circuit after cooled. CONSTITUTION:The refrigerant passes through a compressor 3 and a condenser 4 of a refrigerating machine 2 and is fed into the lower part of an evaporator 7 in a steel pipe pile heat accumulator 5 through a refrigerant pipe 9. Thereby, the upper end of a heat pipe 6 is cooled by the vaporization heat of the refrigerant, and a working fluid 19 evaporates, turns into an upward vapor stream, and comes into contact with the wall surface of a container 18, causing the refrigerant to release the latent heat. The released latent heat vigorously transfers to the evaporator 7 that is cooled by the refrigerant, and water 16 loses heat, reaches 0 deg.C, turns into ice and deposits on the surface of the heat pipe 6. Then, when ice making is completed, a cold water pump 15 is operated to circulate the water through a first air-conditioning branch pipe 20, a first air-conditioning main pipe 14, a first air-conditioning pipe 11, an air-conditioner 10, a second air-conditioning pipe 12, a second air-conditioning main pipe 14, a second air-conditioning branch pipe 21, and the steel pipe pile heat accumulation tank 5, and the circulating water absorbs the cooling load from the air-conditioner 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal storage type air conditioning and cooling method using steel pipe piles as a thermal storage tank.

[Prior Art] There is a large difference in the balance between power demand and supply between daytime and nighttime. This difference is particularly noticeable in the summer when air conditioning is used. Therefore, electric power companies are working to popularize thermal storage systems that store the energy needed for air conditioning at night and use it for daytime cooling. Electric power companies are also conducting research and development of heat storage systems on their own.

The mainstream of conventional heat storage systems is a water heat storage system that utilizes the temperature difference between water. However, water heat storage systems have problems such as the need for a huge heat storage tank to store water.

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

Ice heat storage systems can be broadly divided into static types (ice-on-coil type) and dynamic types (liquid ice type). The static type uses refrigerant (generally Freon or brine) from the refrigerator in the ice making tube installed in the heat storage tank.
The ice is allowed to grow on the surface of the tube. Typical static systems include the direct expansion type, which creates ice on the surface of the ice tube by flowing the refrigerant from the refrigerator directly into the ice tube.
There are brine type, heat pipe type, etc. in which a secondary refrigerant (brine, etc.) is cooled with a refrigerator, and then ice is made in the same way as the direct expansion type.

On the other hand, the dynamic type makes ice separately with an ice making device.
This is stored in a heat storage tank. Typical dynamic systems include the sherbet type, which uses an ice-making device to make sherbet-like ice and stores it in a heat storage tank, and the ice-making system, which grows thin sheets of ice on an ice-making plate and crushes them into ice pieces to store heat. There is a harvest type that is stored in a tank, and a type that cools brine with a low concentration and turns the water in the brine into granular 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 shape of the heat storage tank. For this reason, ice-making tubes are either shaped like a coil wound from the bottom of the heat storage tank toward the top, or made of multiple straight pipes 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 actively grows ice near the refrigerant supply port of the ice making tube. However, as the refrigerant flows through the ice-making tube, its temperature increases.

Therefore, ice grows less near the refrigerant outlet 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 problems occur when ice melts, ie during so-called cooling operation.

Normally, during cooling operation, water from the unfrozen portion of the heat storage tank is first removed by a pump. The cold energy of this water is consumed on the load side. Next, the water that has been deprived of cold energy is returned to the heat storage tank. Next, the ice that returns to the heat storage tank is melted by the increase in temperature of the water. Therefore, if ice is not uniformly obtained over the entire length of the ice-making tube, ice will grow significantly near the refrigerant supply port of the ice-making tube. This ice becomes an ice block. The ice blocks have a small surface area that comes into contact with the water in the heat storage tank. For this reason, the ice blocks are not sufficiently melted. As a result, sufficient cooling and heat required by the load cannot be supplied.

Furthermore, when a plurality of ice-making tubes are arranged in a heat storage tank, the ice that has grown from one ice-making tube to another is connected to each other. In ice heat storage, this connection between ice cubes is called bridging. Furthermore, in the case of a coiled ice making tube, bridging occurs above and below the coil. This bridging is a major hindrance during cooling operation, and adversely affects the performance of the refrigerator not only during cooling operation but also when growing ice in the ice-making tube.

In the dynamic type, the ice making tube is not installed in the heat storage tank, so 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 conveying means such as a pump or a conveyor and stored therein. The ice transported to the heat storage tank is in the form of ice chips or particles. This ice floats on the surface of the heat storage tank. Therefore, if the floating area of ice in the heat storage tank is small, the ice transported to the heat storage tank will gather in one place. As a result, ice chips or granular ice are compacted by buoyancy and form an ice block similar to the static type. For this reason,
When storing manufactured ice in a heat storage tank, the shape of the heat storage tank needs to be somewhat wide in plan.

Compared to conventional water heat storage systems, ice heat storage systems have
The capacity of the heat storage tank can be significantly reduced to one-tenth. As a result, in the ice heat storage system, the heat storage tank can be installed on the rooftop. In addition, there is no need to construct a heat storage tank under a double slab in the basement of a building with a water heat storage system. In addition, constructing a heat storage tank under a double slab in the basement of a building is difficult because there are few buildings that have space to install a huge heat storage tank other than under the double slab, and the cost of constructing a dedicated heat storage tank is low. This is because it becomes expensive.

However, even if the volume of the heat storage tank in an ice heat storage system is reduced to one-tenth, the heat storage tank that can air condition the entire building will be considerably large. Therefore, this heat storage tank cannot be ignored in terms of architectural structure. Therefore, considering the weight of the heat storage tank, the construction cost of the building becomes high. In addition to this,
Modern buildings are becoming taller and taller in order to make effective use of their narrow lot space, and some windows cannot be opened or closed. Therefore, it is becoming more important to adjust the indoor environment using air conditioners. However, the space required to install air conditioning equipment must be kept to a minimum in order to secure living space. Thus, there is still a strong desire for an ice heat storage system to be a vertical ice heat storage system that can be made as compact as possible.

The present invention has been made in view of these points, and provides a thermal storage type air conditioning method using a vertical ice thermal storage system that has high performance, can be miniaturized, and is inexpensive.

[Means for Solving the Problems] The present invention provides a refrigeration circuit that performs cooling by repeatedly condensing and vaporizing a refrigerant by circulating a refrigerant, and a refrigeration circuit that performs cooling by repeatedly condensing and vaporizing a refrigerant, and a cooling system that exchanges cold heat of the refrigeration circuit with cold water flowing through a cold water circulation path. In a method of performing air conditioning and cooling via a load type air conditioning circuit using cold water, the refrigeration circuit is formed of a long heat pipe, the heat pipe is housed in a long steel pipe pile heat storage tank, and the heat pipe is A cold heat source surrounding the heat radiating part is provided, a refrigerant is circulated through the cold heat source, ice is made by the cooling action of the refrigerant around the heat pipe heat radiating part, and then the cold water flowing through the cold water circulation path is This is a regenerative air conditioning and cooling method characterized by returning the cold water to a load type air conditioning circuit after the temperature has been lowered.

[Function] The heat storage type air conditioning and cooling method of the present invention uses steel pipe piles as a heat storage tank. Therefore, space for a heat storage tank is not required. In addition, the soil around the steel pipe piles acts as a heat storage material with a large heat capacity. Therefore, during 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 during air conditioning operation, the sufficiently cooled soil acts as a cold heat source, lowering the water temperature inside the steel pipe pile and contributing to air conditioning.

Further, in the regenerative air conditioning method of the present invention, a sufficiently long heat pipe is used as the ice making tube.

Heat exchange in the heat pipe is performed using the latent heat of evaporation and condensation of the working fluid. Therefore, the surface temperature of the entire heat pipe becomes close to the vapor temperature of the working fluid inside the tube. That is, by making the heat dissipation section sufficiently long, it is possible to obtain an ice layer having a uniform thickness over substantially the entire length of the heat pipe. As a result, excessive icing inside the steel pipe pile can be prevented, a sufficient amount of icing can be ensured, and daytime air conditioning operation can be performed efficiently.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings.

FIG. 1 is an explanatory diagram showing a system to which the present invention is applied to cool a building with four floors above ground and one floor underground.

1 in the figure is a building. On the ground surface outside Building 1,
A refrigeration device 2 is installed. The refrigeration device 2 includes a compressor 3
and a condenser 4. A plurality of long steel pipe piles are attached to the bottom of the building 1. This steel pipe pile serves as a building foundation member and also acts as a heat storage tank (hereinafter abbreviated as steel pipe pile heat storage tank 5). The steel pipe pile heat storage tank 5 is
It is buried deep underground. Further, each steel pipe pile heat storage tank 5 includes an extremely long heat vibro and an evaporator 7 attached to the upper end of the heat vibro.

A first refrigerant pipe 8 is attached to the compressor 3 . A second refrigerant pipe 9 is attached to the condenser 4 . Each refrigerant pipe 8.9 is branched and extends to each steel pipe pile heat storage tank 5, and is connected to the evaporator 7 in each steel pipe pile heat storage tank 5. In addition, the refrigeration device 2
, an evaporator 7, a first refrigerant pipe 8, and a second refrigerant pipe 9 constitute a refrigeration circuit.

On the other hand, an air conditioner 10 is installed on each floor.

A first air conditioning pipe 11 and a second air conditioning pipe 12 are attached to each air conditioner 10. Air conditioning piping 1 for container 1
1 is connected to a first air conditioning piping main pipe 13. 1st
The air conditioning piping main pipes 3 are further branched and extended into the steel pipe pile heat storage tank 5, respectively. That is, the first air conditioning piping main pipe 13 and the inside of each steel pipe pile heat storage tank 5 are communicated through the first branch air conditioning piping 20. Similarly to the first air conditioning piping 11, the air conditioning piping 12 of each node 2 is extended into the inside of each steel pipe pile heat storage tank 5 by a second branch air conditioning piping 21 via the second air conditioning piping main pipe 14. . Furthermore, a cold water pump 15 is attached to the first air conditioning main pipe 13 . Air conditioner 10, steel pipe pile heat storage tank 5, first air conditioning piping 11, first air conditioning piping main pipe 13, first branch air conditioning piping 20, cold water pump 15, second air conditioning piping 12, second air conditioning piping main pipe 14 and the second branch air conditioning pipe 21 constitute a load type air conditioning circuit.

FIG. 2 is an explanatory diagram of the main parts of the steel pipe pile heat storage tank 5 used in the present invention. The steel pipe pile heat storage tank 5 includes a heat vibro and an evaporator 7 that functions as a cold heat source attached to the upper end of the heat vibro. Moreover, water 16 is accommodated inside the steel pipe pile heat storage tank 5 . Ice 17 of a predetermined thickness is deposited on the surfaces of the heat vibro 1 and the evaporator 7. A first refrigerant pipe 8 is connected to the top of the evaporator 7 . Further, a second refrigerant pipe 9 is connected to the lower part of the evaporator 7. A first branch air conditioning pipe 20 is inserted into the steel pipe pile heat storage tank 5 . The first branch air conditioning pipe 20 extends to the vicinity of the bottom of the steel pipe pile heat storage tank 5 . In addition, the steel pipe pile heat storage tank 5 includes a second branch air conditioning pipe 21.
is also inserted. The second branch air conditioning pipe 21 extends to the vicinity of the evaporator 7.

FIG. 3 is an explanatory diagram of the heat vibro used in the present invention. Heat Vibro uses a small amount of working fluid 1 as a heat medium.
9 is housed inside a container 18 and both ends thereof are sealed. Furthermore, a wick exhibiting capillary action is provided inside the container 18.

The heat pipe operates as follows. First, one end of the heat pipe is heated to evaporate the working fluid inside. At this time, the hydraulic fluid is directed to the other end with relatively low pressure,
A steam flow is generated. The vapor flow 2 contacts the inner wall of the heat pipe at the other end, releases latent heat, and condenses. The condensed working fluid flows along the inner wall of the pipe and returns to the evaporation part. The heat pipe transfers heat by repeating this operation.

Therefore, conveyance equipment such as a pump can be made unnecessary.

The heat storage air conditioning system configured as described above performs cooling as follows.

This system consists of a refrigeration circuit equipped with a refrigeration device to grow ice on the surface of the heat pipe, and a load-type air conditioning circuit to utilize the cold heat of the ice in the steel pipe pile heat storage tank.

First, a night-time refrigeration circuit is operated using cheap electricity, generally called late-night electricity, and an ice-making operation is performed in which the ice necessary for cooling on -day is grown and stored on the surface of the heat pipe of the steel pipe pile heat storage tank. The ice-making operation will be carried out for 10 hours from 10pm to 8am the next morning, when late-night power is supplied by the power company.

To make ice using a heat pipe, first, the refrigerant (hereinafter abbreviated as refrigeration refrigerant) that has passed through the compressor 3 and condenser 4 of the refrigeration device 2 is sent to the evaporator 7 . At this time, the frozen refrigerant passes through the second refrigerant pipe 9 as shown in FIG.
It is supplied to the lower part of the evaporator 7 in the steel pipe pile heat storage tank 5. Thereby, the upper end of the heat vibro is cooled by the heat of vaporization of the freezing refrigerant.

When the upper end of the Heat Vibro is cooled, the water 16 in the steel pipe pile heat storage tank 5 becomes a heating source for the Heat Vibro, as shown in FIG. Therefore, the hydraulic fluid 19 in the container 18 is
It evaporates into an upward vapor stream. This vapor stream contacts the walls of the container 18, releases latent heat, is condensed again, and returns to the bottom. The released latent heat actively moves to the evaporator 7, which is cooled by a refrigerant. Therefore, the water 16 loses heat and eventually reaches 0°C. As a result, the water 16 becomes ice 17 and forms ice on the surface of the heat vibro. In this way, an ice layer of uniform thickness is grown over almost the entire length of the heat vibro.

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

In this way, the refrigeration circuit continues to operate until 8 a.m., when the late-night power supply ends, and the required amount of ice grows on the surface of the heat pipe to store cold heat.

Next, from 8 a.m., when the ice-making operation is completed, the load-type air conditioning circuit is activated to perform cooling operation. First, by operating the cold water pump 15, the first branch air conditioning piping 20, the first air conditioning piping main pipe 13, the first air conditioning piping 11, the air conditioner 10, the air conditioner 10. Second air conditioning pipe 12, second air conditioning pipe main pipe 1
4, second branch air conditioning piping 2] and the water in the steel pipe pile heat storage tank 5 circulates. Through this circulation, the circulating water is transferred to the air conditioner 1.
Absorbs the cooling load from 0. The circulating water heated by the cooling load (e.g. 12°C) is transferred to the second tank as shown in Figure 2.
It flows into the vicinity of the upper part of the steel pipe pile heat storage tank 5 through the branch air conditioning piping 21 . This circulating water is cooled by melting the ice that has grown on the surface of the Heat Vibro (for example, 4
~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 maintained in a good air-conditioned condition. Note that this cooling operation can be continued until 22:00 at night when the ice making operation starts. If all the ice 17 in the steel pipe pile heat storage tank 5 is consumed during that time and an even larger air conditioning load occurs, the refrigeration circuit can be operated again to perform backup operation.

In this way, the ice making operation at night and the cooling operation during the day can be performed satisfactorily.

Furthermore, it is possible to reduce construction costs by eliminating the need for thermal insulation of the heat storage tank, which is essential in conventional heat storage systems.

[Effects of the Invention] As explained above, in the heat storage type air conditioning and cooling method of the present invention, the steel pipe pile can also be used as a heat storage tank, so that the space for the heat storage tank can be saved. In addition, since it is possible to directly melt water and extract cold water at the most stable temperature of around 4°C for a long period of time, the amount of water supplied by the air conditioner can be reduced, resulting in energy savings. Furthermore, in the heat storage type air conditioning and cooling method of the present invention, heat loss in the heat storage tank can be prevented.

As described above, the regenerative air conditioning method of the present invention allows the use of smaller equipment and reduces initial costs and running costs.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing a system for cooling a building with four floors above ground and one floor underground by applying the present invention, and Figure 2 is an explanatory diagram of the main parts of a steel pipe pile heat storage tank used in the method according to the present invention. , 3rd
The figure is an explanatory diagram of a heat pipe used in the present invention. 1... Building, 2... Refrigeration equipment, 3... Compressor, 4
...Condenser, 5... Steel pipe pile heat storage tank, 6... Heat pipe, 7... Evaporator, 8... First refrigerant piping, 9
...Second refrigerant pipe, 10...Air conditioner, 11...
First air conditioning pipe, 12... Second air conditioning pipe, 13...
・First air conditioning piping main pipe, 14...Second air conditioning piping main pipe, 15...Cold water pump, 16...Water, 17...Ice, 18...Container, one...Operation Liquid, 20...
First branch air conditioning piping, 21...Second 7 branch air conditioning piping. 8 191-

Claims (1)

[Claims] A refrigeration circuit that performs cooling by repeatedly condensing and vaporizing refrigerant by circulating a refrigerant, and the cold heat of the refrigeration circuit is exchanged with cold water flowing in a chilled water circulation path, and the chilled water performs air conditioning and cooling via a load type air conditioning circuit. In the method, the refrigeration circuit is formed of a long heat pipe, the heat pipe is housed in a long steel pipe pile heat storage tank, and a cold heat source part surrounding a heat radiation part of the heat pipe is provided, A refrigerant is circulated through the heat pipe source, and then ice is made by the cooling action of the refrigerant around the heat pipe heat dissipation section.Next, after the cold water flowing through the cold water circulation path is lowered in temperature, the cold water is sent to a load type air conditioning circuit. A heat storage type air conditioning cooling method characterized by returning heat.