TWI546510B - Heat exchange system - Google Patents

Description

Heat exchange system

The present invention relates to a heat exchange technique for recovering heat from water and/or discharging heat to water for use in a heat load including an air conditioner and a hot water supply.

In Japan, the temperature in the ground is about 15 °C throughout the year. The winter temperature in Japan is much lower than 15 °C, while the summer temperature is much higher than 15 °C.

Therefore, it is considered that such a temperature difference is effectively utilized for, for example, a heat load including an air conditioner and a hot water supply.

To this end, the inventors have repeatedly studied techniques for recovering geothermal heat and utilizing them.

In the prior art, the recovery of geothermal heat (or heat removal into the ground) is to circulate a well-known liquid phase heat medium (brine) in a pipe buried in the ground, and exchange heat with the liquid phase heat medium and geothermal heat. (The so-called "sensible heat - sensible heat exchange").

However, in order to secure the area required for heat exchange between the heat medium and the geothermal heat, the diameter of the piping through which the refrigerant flows can be increased.

Further, in order to recover heat such as an air conditioner that can be appropriately operated, it is necessary to embed a very long pipe in a deep region of the ground.

Further, in order to embed a pipe having a large diameter in a deep region in the ground, there is a problem that a large cost is required.

In other conventional technologies, for example, a technique in which groundwater is used as a heat medium and heat is stored in the ground is also proposed (see Patent Document 1).

However, in such a conventional technique (Patent Document 1), it is necessary to dig a vertical well, and it is necessary to increase the depth of the vertical pit when the amount of stored heat is increased, and thus the above problem cannot be solved.

[Advanced technical literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2010-38507

The present invention has been made in view of the problems of the above-described conventional techniques, and aims to propose a heat exchange system which has high heat exchange efficiency and can save labor and cost required for construction.

The inventors have found through various studies that when carbon dioxide (CO ₂ ) is used as the heat medium (or refrigerant), heat is recovered from the water to the heat medium during operation of the greenhouse, and heat is used when the cold room is operated. The heat of the medium discharged to the water can improve the heat exchange efficiency. Further, when the temperature of carbon dioxide (CO ₂ ) which is a heat medium (or a refrigerant) is 5 to 40 ° C, the heat exchange efficiency becomes extremely high.

The present invention is based on such knowledge and is proposed by the proponent.

The heat exchange system according to the present invention includes: a water storage device (150, GH); and a piping system (La), which is immersed in the water of the water storage device (150, GH) and has the water storage device (150, GH) The water in the water exchange function, and includes: a compression type air conditioner having an outdoor unit (1), an indoor unit (2), an air conditioning load (3), an air compressor (4), and a four-way valve (V4) The piping system (La) is connected to the outdoor unit (1), wherein the heat medium flowing inside the piping system (La) is carbon dioxide, and the heat storage or condensation heat of the carbon dioxide is used to form the water storage device (150). Heat exchange in the water in GH), in order to utilize the heat of vaporization or condensation heat of the aforementioned carbon dioxide to heat the water in the water storage device (150, GH) In exchange, the temperature of the carbon dioxide flowing in the region of the piping system (La) exposed to the water storage device (150, GH) is set to 5 ° C to 40 ° C, and the piping system (La) is composed of two layers. The tube (9) is configured such that the inner tube (91) flows carbon dioxide in the liquid phase, the outer tube (92) flows through the carbon dioxide in the gas phase, and the inner tube (91) and the outer tube (92) pass through the pump (5). The first opening/closing valve (V1) is provided on the discharge port (5o) side of the pump (5), and the second opening/closing valve (V2) is provided on the suction port (5i) side of the pump (5). A branch line (La5) is provided on the outdoor unit (1) side of the second on-off valve (V1, V2).

A heat exchange system according to the present invention includes: a water storage device (150, GH); and a piping system (La) immersed in the water of the water storage device (150, GH) and having the water storage device (150, The water in GH) performs the function of heat exchange, and has a compression type air conditioner having an outdoor unit (1), an indoor unit (2), an air conditioning load (3), an air compressor (4), and a four-way valve (V4). The piping system (La) is connected to the outdoor unit (1), wherein the heat medium flowing inside the piping system (La) is carbon dioxide, and the water vaporizing heat or condensation heat of the carbon dioxide is used to form the water storage device ( 150, GH) heat exchange, in order to utilize the heat of vaporization or condensation heat of the carbon dioxide to exchange heat with water in the water storage device (150, GH), to form an exposure in the piping system (La) The temperature of the carbon dioxide flowing in the region of the water storage device (150, GH) is set to 5 ° C to 40 ° C, and the piping system (La) is composed of a double tube (9), and the inner tube (91) flows through the liquid phase. The carbon dioxide has a configuration in which the outer tube (92) flows through the carbon dioxide in the gas phase, and the inner tube (91) and the outer tube (92) are connected via a pump (5), and the pump (5) is discharged. The (5o) side is connected to the inner tube (91) via a line (93) through which the first opening/closing valve (Vb3) is placed, and the second opening/closing valve (Vb1) is disposed through the suction port (5i) side of the pump (5). The line (94) is connected to the outer tube (92), and the lower end of the inner tube (91) is connected to the outer tube (92) via the third opening and closing valve (Vb2) And a control unit (50) for switching between the cold room and the warm room, the control unit is configured to close the first and second opening and closing valves (Vb3, Vb1) when the greenhouse is closed, and to open the third opening and closing valve (Vb2), and in the cold room The first and second on-off valves (Vb3, Vb1) are opened, and the third on-off valve (Vb2) is closed to activate the pump (5).

Preferably, the piping system (La) is provided with a discharge valve (Va) and a carbon dioxide supply amount adjusting valve (Vc), and has a control unit (50A) having a discharge valve ( Va) and the valve opening degree of the carbon dioxide supply amount adjusting valve (Vc) to determine the function of the carbon dioxide circulation amount; the carbon dioxide circulation amount is compared with the predetermined amount to determine whether the function is appropriate; if the carbon dioxide circulation amount is appropriate, the maintenance is performed The valve opening degree of the bleed valve (Va) and the carbon dioxide supply amount adjusting valve (Vc) increases the valve opening degree of the bleed valve (Va) and/or reduces the carbon dioxide supply amount adjusting valve (Vc) when the amount of carbon dioxide circulating is excessive. The valve opening degree reduces the valve opening degree of the discharge valve (Va) and/or the valve opening degree of the carbon dioxide supply amount adjustment valve (Vc) when the amount of carbon dioxide circulation is too small.

In the present invention, in the case of the operation of the cold room, the temperature of the carbon dioxide flowing in the area of the piping system (La) to be entered into the water storage device (150, GH) is plotted in Fig. 26(A) and Fig. 28 The temperature shown by O": the temperature measured by the temperature sensor 7 in Fig. 4) and the water temperature in the water storage device (150, GH) (Fig. 26 (A), Fig. 28 is a characteristic curve indicated by a broken line The temperature: the temperature measured by the temperature sensor TW1 in Fig. 4) is preferably 60 ° C or less.

Alternatively, in the present invention, in the case of performing the greenhouse operation, the temperature of the water in the water storage device (150, GH) (the temperature indicated by the characteristic curve of the broken line in Fig. 27(A): the temperature sensor in Fig. 3 The temperature measured by TW1) and the temperature of the carbon dioxide flowing in the area of the piping system (La) to be entered into the water storage device (150, GH) (the temperature indicated by "O" is plotted in Fig. 27(A): The temperature difference in the temperature measured by the temperature sensor 6 in Fig. 3 is preferably 30 ° C or less.

Further, in the present invention, it is preferable that the piping system (La) is divided into a plurality of systems.

Alternatively, it is preferable that the piping system (La) is arranged in a spiral shape.

When the present invention is implemented, the water storage device can be configured by a so-called water tank (150) or a water reservoir (GH).

Further, the water storage device may be configured by an culvert or a ditch (or an open channel) having a water depth capable of immersing the piping system (La) through which the heat medium flows.

According to the present invention having the above configuration, carbon dioxide is used as the heat medium, and the heat of vaporization (or condensation heat) of carbon dioxide and the sensible heat retained by the water in the water storage device (sink 150, reservoir GH) are exchanged. That is, when the heat retained by the water in the water storage device (sink 150, reservoir GH) is recovered, the carbon dioxide in the liquid phase is recovered from the water and the heat is discharged to the water in the water storage device. In the case, the carbon dioxide in the gas phase discharges the condensation heat and condenses in the water (G) in the water storage device.

In other words, the latent heat of the heat medium composed of carbon dioxide and the sensible heat of the water in the water storage device perform so-called "latent heat-sensible heat exchange".

Here, the "latent heat-sensible heat exchange" is compared with the conventional "sensible heat-sensible heat exchange". Since a large amount of heat can be recovered or discharged per unit amount of heat medium, the heat exchange efficiency is greatly improved. Upgrade.

Further, according to the present invention, the temperature of the carbon dioxide flowing in the region exposed to the water storage device (150) is set to 5 ° C to 40 ° C, and the setting achievement is a temperature at which carbon dioxide is compressed to increase the pressure, and carbon dioxide is not liquefied, that is, The temperature near the critical point (31.1 ° C). As will be described later, according to experiments by the inventors, the temperature of carbon dioxide flowing in a region exposed to the water storage device (sink 150, reservoir GH) is a critical point (31.1 ° C). Nearly, the heat exchange efficiency between carbon dioxide and water will increase.

Here, when the temperature of the carbon dioxide flowing through the area where the water storage device is exposed is too high (the case where the temperature is higher than 40 ° C), the heat exchange efficiency in the cold room is lowered, and it is clear from the experiment of the inventor described later. .

On the other hand, when the temperature of the carbon dioxide flowing through the area where the water storage device is exposed is too low (when the temperature is lower than 5 ° C), the pressure of the heat medium in the piping system (La, 9) becomes a low pressure, which may not be suitable. In the case of letting the heat medium (carbon dioxide) naturally circulate.

In addition, in the present invention, carbon dioxide is used as the heat medium (refrigerant), and the carbon dioxide is larger in heat capacity than the brine used in the prior art.

Therefore, according to the present invention, the heat medium can efficiently recover heat from the water in the water storage device or can be efficiently discharged, so that the piping system (La, 9) through which the heat medium flows can be made short and thin. Further, the labor and cost required to provide the piping (La, 9) through which the heat medium flows can be greatly reduced.

Here, in the case of a conventional technique in which brine is used as a heat medium and heat exchange is performed by heat medium and geothermal heat, it is necessary to arrange the piping in the ground through which the brine is circulated, or to arrange the ground in the foundation pile. In the middle of the piping, when the foundation pile is constructed, it will incur additional costs.

Further, in the case where the piping in the ground in which the brine is supplied is not disposed in the vicinity of the pile, it is necessary to excavate the well for piping in the ground, and thus the cost required for the derivation.

On the other hand, in the present invention, it is not necessary to embed the piping system (La, 9) in the ground (G), and the piping system (La, 9) can be made short and thin, so that the conventional technology can be greatly reduced. Labor and cost derived from the burying of the piping system.

Further, in the present invention, the piping system (La) through which the heat medium flows is constituted by a double tube (9), for example, in the water in the water storage device. In the case of the retained heat (warm operation), the carbon dioxide in the liquid phase sent from the heat exchanger (for example, the outdoor unit 1) is lowered in the inner tube (91) of the double tube (9). Here, since the specific gravity of carbon dioxide in the liquid phase is larger than the ratio of carbon dioxide in the gas phase, carbon dioxide in the liquid phase falls downward due to its mass.

On the other hand, when the carbon dioxide in the liquid phase recovers the heat of vaporization from the water in the water storage device and vaporizes, the specific gravity of the carbon dioxide in the gas phase is smaller than the specific gravity of the carbon dioxide in the liquid phase, and faces the heat exchanger (for example, outdoor). The machine 1) is raised in the outer tube (92) of the double tube (9).

Therefore, even if no external power is provided, the carbon dioxide in the liquid phase and the carbon dioxide in the gas phase will flow through the double tube.

In the present invention, when the piping system (9D) in the water storage device is installed in a plurality of systems, the heat retained by the water in the water storage device can be efficiently recovered, and the heat can be discharged to the water in the water storage device.

Here, when the piping system in the water storage device is arranged in a spiral shape (9E, 9F), since the length in the circumferential direction is three times the diameter, the depth of the excavation may be about 1/3 of that of the prior art.

In the present invention, in the case of the operation of the cold room, the temperature of the carbon dioxide flowing in the area where the water storage equipment (150, GH) enters the piping system (La, 9) (in Fig. 26(A), Fig. 28) The temperature indicated by "O": the temperature measured by the temperature sensor 7 in Fig. 4) and the water temperature in the water storage device (150, GH) (Fig. 26(A), Fig. 28, the characteristic curve of the broken line When the temperature difference of the temperature indicated by the temperature sensor TW1 in Fig. 4 is 60 ° C or less, the cold room operation can be performed without lowering the efficiency of the cold room. This was confirmed by experiments by the inventors.

Alternatively, in the present invention, in the case of the warm room operation, the water temperature in the water storage device (150, GH) (the temperature indicated by the characteristic curve of the broken line in Fig. 27(A): the temperature sensor TW1 in Fig. 3 The measured temperature) and the temperature of the carbon dioxide flowing in the area of the piping system (La, 9) to be entered into the water storage device (150, GH) (the temperature indicated by "O" is plotted in Fig. 27(A): When the temperature difference of the temperature measured by the temperature sensor 6 in 3 is 30 ° C or less, the warm room operation can be performed without lowering the efficiency of the greenhouse. This was also confirmed by experiments by the inventors.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In the illustrated embodiment, an air conditioning system is exemplified as an example of the heat exchange system.

In other words, in the illustrated embodiment, for example, the air conditioner 3 is connected to the heat load.

Fig. 1 to Fig. 16 show a first embodiment (including various modifications) of the present invention.

Here, in order to make the description of the operation easy to understand, FIG. 1, FIG. 3, and FIG. 4 show that one part of the piping (La) immersed in the water tank is different from the actual structure. The configuration of the piping (La) immersed in the water tank will be described later.

In addition, the control system (control unit 50, etc.) of the cold and warm room switching control is illustrated in FIG. 1, but the illustration of the control system is omitted in FIGS. 3 and 4.

First, the first embodiment will be briefly described with reference to Fig. 1 .

In the air conditioning system (heat exchange system) indicated by the reference numeral 100 in the first embodiment, the first heat exchanger (hereinafter referred to as "outdoor unit") and the second heat exchanger (hereinafter referred to as "indoor" "Air machine" 2, a heat load air conditioner 3 (including a warm water floor heating device, etc.), a water tank 150 belonging to a water storage device, a piping system La immersed in the water tank 150, a first heat medium line Lb, and 2 heat medium pipeline Lc.

The piping system La immersed in the water tank 150 is provided with a first heat exchanger 1, a pump 5, opening and closing valves V1, V2, and temperature sensors 6, 7. In addition, liquid phase carbon dioxide or gas phase carbon dioxide which is a heat medium flows in the piping system La (hereinafter, carbon dioxide is described as "CO ₂ ").

The piping system La has lines La1 to La5.

In order to measure the water temperature in the water tank 150, a temperature sensor (water temperature sensor) TW1 is disposed in the water tank 150.

The line La1 connects the discharge port 5o of the pump 5 to the valve V1.

The line La2 connects the valve V1 to the connection port 11 of the outdoor unit 1. In the line La2, a branch point B1 is provided in the vicinity of the valve V1, and a temperature sensor 6 is interposed in the vicinity of the port 11.

The line La3 connects the connection port 12 of the outdoor unit 1 and the valve V2. In the line La3, a branch point B2 is provided in the vicinity of the valve V2, and a temperature sensor 7 is interposed in the vicinity of the port 12.

The line La4 connects the valve V2 to the suction port 5i of the pump 5.

The line La5 connects the branch point B1 and the branch point B2 and bypasses the branch line of the pump 5.

In FIG. 1, the piping system La is a water W immersed in the water tank 150 except for the piping La2 of the piping system La and the part of the outdoor unit 1 side of the line La3. The configuration of the piping system La for the water W soaked in the water tank 150 will be described later with reference to Figs. 5 to 13 .

In FIG. 1, the first heat medium line Lb is provided with an outdoor unit 1, an indoor unit 2, an air compressor 4, a pressure reducing valve V3, and a four-way valve V4, and constitutes a compression type air conditioner. Further, a primary brine (for example, chlorofluorocarbon R134) which is a heat medium flows through the heat medium line Lb.

The first heat medium line Lb has lines Lb1 to Lb5.

The line Lb1 connects the discharge port 4o of the air compressor 4 and the port Vp1 of the four-way valve V4.

The line Lb2 connects the port Vp2 of the four-way valve V4 to the connection port 21 of the indoor unit 2.

The line Lb3 connects the connection port 22 of the indoor unit 2 and the connection port 13 of the outdoor unit 1. A pressure reducing valve V3 is interposed in the line Lb3.

The line Lb4 connects the connection port 14 of the outdoor unit 1 and the port Vp3 of the four-way valve V4.

The line Lb5 connects the port Vp4 of the four-way valve V4 and the suction port 4i of the air compressor 4.

The second heat medium line Lc is provided with an indoor unit 2 and an air conditioner 3. A secondary brine (for example, water) belonging to a heat medium flows through the heat medium line Lc.

The second heat medium line Lc has a line Lc1 and a line Lc2.

The line Lc1 connects the connection port 31 of the air conditioner 3 and the connection port 23 of the indoor unit 2. The line Lc2 connects the connection port 24 of the indoor unit 2 and the connection port 32 of the air conditioner 3.

As shown in Fig. 1, the heat exchange system 100 is provided with a control unit 50 that is a control means. The control unit 50 is connected to the air compressor 4, the pump 5, and the opening and closing valves V1, V2 via the control signal line So.

Next, the switching control of the cold room/warm room during the operation of the air conditioner 3 of Fig. 1 will be described with reference to Fig. 2 .

In step S1 of Fig. 2, the air conditioner 3 is operated by operating a control panel (not shown) including the control unit 50 by automatic control or manual operation.

In step S2, it is determined whether the warm room operation or the cold room operation is to be performed by the automatic control or the manual operation to perform the determined operation.

When the greenhouse operation is performed ("warm house" in step S2), the control unit 50 closes the opening and closing valves V1, V2 of the piping system La immersed in the water tank 150 to stop the pump 5 disposed in the piping system La (step S3). ).

Next, proceeding to step S4, the four-way valve V4 is switched to the warm room side. When the four-way valve V4 is switched to the warm room side, the port Vp1 of the four-way valve V4 communicates with the port Vp2, and the port Vp3 communicates with the port Vp4 (refer to FIG. 3).

On the other hand, if the operation of the cold room is performed ("Slow room" in step S2), the opening and closing valves V1, V2 that are interposed in the piping system La are opened by the control unit 50, and the pump 5 interposed in the piping system La is actuated. (Step S5).

Next, proceeding to step S6, the four-way valve V4 is switched to the cold room side. When the four-way valve V4 is switched to the cold room side, the port Vp1 of the four-way valve V4 communicates with the port Vp3, and the port Vp2 communicates with the port Vp4 (refer to FIG. 4).

When step S4 or step S6 is completed, the process proceeds to step S7, and the control unit 50 operates the air compressor 4 interposed in the first heat medium line Lb to perform the warm room operation or the cold room operation, and proceeds to step S8.

In step S8, it is judged whether or not the control unit 50 has performed the operation of the warm room operation or the cold room operation. If the end operation has been completed (YES in step S8), the control is ended.

On the other hand, if the end operation is not performed (NO in step S8), the process returns to step S2, and the steps from step S2 onwards are repeated.

The case of performing the operation of the greenhouse will be described with reference to FIG. 3.

At the time of the warm room operation shown in FIG. 3, as described above, when the opening and closing valves V1 and V2 interposed in the piping system La are closed, the pump 5 interposed in the piping system La is stopped.

Next, the four-way valve V4 interposed in the first heat medium line Lb is switched to the warm room side, the port Vp1 of the four-way valve V4 is communicated with the port Vp2, and the port Vp3 is communicated with the port Vp4.

Then, the air compressor 4 is actuated, and the heat medium (for example, chlorofluorocarbon R134) is compressed to become a high-temperature high-pressure gas phase chlorofluorocarbon, which is discharged from the discharge port 4o of the air compressor 4.

The high-temperature high-pressure gas phase chlorofluorocarbon which is discharged from the air compressor 4 flows into the indoor unit from the first connection port 21 of the indoor unit 2 via the line Lb1, the port Vp1 of the four-way valve V4, the port Vp2, and the line Lb2. 2 heat exchange unit 2h.

In the heat exchange unit 2h of the indoor unit 2, a high-temperature high-pressure gas phase chlorofluorocarbon system and a heat medium flowing through the second heat medium line Lc (a heat medium flowing from the air conditioner 3 to the indoor unit 2 via the line Lc1: for example, water ) Perform heat exchange. The water (heat medium) flowing through the heat medium line Lc is heated by the heat exchange in the indoor unit 2, and the high-temperature high-pressure gas phase chlorofluorocarbon loses the heat of vaporization and condenses to become a high-pressure liquid phase chlorofluorocarbon.

The water that is heated by the indoor unit 2 is sent from the line Lc2 to the air conditioner 3, and the heat sink (not shown) of the air conditioner 3 releases heat, and the room in which the air conditioner 3 is installed is executed. After the heat is released by the heat sink (not shown), the water belonging to the heat medium is again sent to the indoor unit 2 via the line Lc1.

On the other hand, the high-pressure liquid phase chlorofluorocarbon which is condensed in the indoor unit 2 flows from the connection port 22 of the indoor unit 2 to the heat exchange unit 1h in the outdoor unit 1 from the connection port 13 of the outdoor unit 1 via the line Lb3. When the high-pressure liquid phase chlorofluorocarbon flows through the line Lb3, it is decompressed by the pressure reducing valve V3 to become a low-pressure liquid phase chlorofluorocarbon.

1h in the heat exchange portion in the outdoor unit 1, low-pressure liquid flowing through the system and the Freon was soaked in the water tank piping system La 150 in the vapor phase CO ₂ by heat exchange. Next, the gas phase CO ₂ condensation heat of the low pressure liquid into Freon, thus flows through the vapor piping system La-based CO ₂ and condensed into a liquid phase CO _2. That is, in the heat exchange portion 1h, the low pressure liquid and vapor CO ₂ Freon-based gas by CO ₂ condensation heat of the latent heat of vaporization genus hot heat exchanger, a so-called "latent heat - exchange latent hot "." As a result, the low-pressure liquid phase chlorofluorocarbon is vaporized to become a low-pressure gas phase chlorofluorocarbon.

The low-pressure gas phase chlorofluorocarbon which has been vaporized in the outdoor unit 1 flows into the inflow port 4i of the air compressor 4 via the connection port 14 of the outdoor unit 1, the line Lb4, the ports Vp3, Vp4 of the four-way valve V4, and the line Lb5. . Then, the air compressor (F) which is compressed by the air compressor 4 and becomes high temperature and high pressure is discharged from the discharge port 4o.

On the other hand, the liquid phase CO ₂ condensed in the outdoor unit 1 is discharged from the connection port 11 of the outdoor unit 1, flows through the line La2, and falls due to its own weight. When flowing through the line La2, the liquid phase CO ₂ is supplied with vaporization heat due to the water W in the water tank 150 and is phase-changed into a gas phase CO ₂ .

Since the on-off valves V1 and V2 are closed during the operation of the greenhouse, the CO ₂ flowing through the line La2 bypasses the branch point B1 and flows through the La5, and flows into the line La3 from the branch point B2.

The CO ₂ flowing into the line La3 is sufficiently supplied with heat retained by the water W in the water tank 150 to be vaporized.

Here, the specific gravity of the liquid phase CO ₂ discharged from the outdoor unit 1 is larger than that of the gas phase CO ₂ . Thus, CO ₂ gas in line La3 based liquid CO ₂ is pressed in line La3 camel rises. Therefore, it is not necessary to operate the pump 5 for CO ₂ transportation during the operation of the greenhouse.

The gas phase CO ₂ rising in the line La3 flows into the outdoor unit 1 from the connection port 12. Then, as described above, heat of condensation is applied to the low-pressure gas phase chlorofluorocarbon.

Next, the case of performing the operation of the cold room will be described with reference to FIG.

At the time of the operation of the cold room of Fig. 4, as described above, the opening and closing valves V1 and V2 interposed in the piping system La are opened, and the pump 5 interposed in the piping system La is actuated.

In the piping system La, the liquid phase CO ₂ pressurized by the pump 5 rises at the discharge port 5o, the line La1, the opening and closing valve V1, and the line La2. Then, it flows into the heat exchange part 1h in the outdoor unit 1 via the connection port 11.

In the outdoor unit 1, the liquid phase CO ₂ system and the high-pressure gas phase chlorofluorocarbon discharged from the discharge port 4o of the air compressor 4 exchange heat of vaporization. The liquid phase CO _{2 to which the} heat of vaporization is introduced is gas phase CO ₂ , and flows into the suction port 5i of the pump 5 via the connection port 12, the line La3, the opening and closing valve V2, and the line La4.

Here, since the negative pressure of the suction port 5i of the pump 5 acts on the line La3, the gas phase CO ₂ vaporized in the outdoor unit 1 falls in the line La3 toward the water tank 150.

The gas phase CO ₂ system discards the condensation heat of the water W in the water tank 150 during the lowering of the line La3 and condenses to form a liquid phase CO ₂ . Then, depending on the negative pressure of the suction port 5i of the pump 5, the liquid phase CO ₂ is not branched in the line La5, and all the volume flows through the line La4 and is sucked into the suction port 5i of the suction pump 5.

When the cold room is running, the four-way valve V4 interposed in the first heat medium line Lb is switched to the cold room side, the port Vp1 of the four-way valve V4 is communicated with the port Vp3, and the port Vp2 is communicated with the port Vp4. Then, the air compressor 4 is started, and the chlorofluorocarbon which is compressed by the heat medium and which is heated at a high temperature and a high pressure is discharged from the discharge port 4o.

The high-temperature high-pressure gas phase chlorofluorocarbon discharged from the air compressor 4 flows into the outdoor unit 1 from the connection port 14 of the outdoor unit 1 via the line Lb1, the port Vp1 of the four-way valve V4, the port Vp3, and the line Lb4. Exchange unit 1h.

In the heat exchange unit 1h of the outdoor unit 1, a high-temperature and high-pressure gas phase chlorofluorocarbon system puts heat of condensation (heat exchange) into the liquid phase CO ₂ flowing from the line La2 of the piping system La into the connection port 11, and is condensed to become a high pressure. Liquid phase chlorofluorocarbon. At that time, the liquid phase CO _{2 of the} piping system La is vaporized.

The high-pressure liquid phase chlorofluorocarbon which is condensed in the outdoor unit 1 is discharged from the connection port 13 toward the line Lb3, and is decompressed by the pressure reducing valve V3 interposed in the line Lb3 to become a low-pressure liquid phase chlorofluorocarbon. The low-pressure liquid phase chlorofluorocarbon flows into the heat exchange portion 2h of the indoor unit 2 from the connection port 22.

In the heat exchange unit 2h, the low-pressure liquid phase chlorofluorocarbon system flowing through the first heat medium line Lb and the water (hot coal) flowing through the second heat medium line Lc exchange heat, and the heat of vaporization is introduced to become a low pressure. Gas phase chlorofluorocarbon. At that time, the water flowing through the second heat medium line Lc is lowered to a temperature corresponding to the amount of the chlorofluorocarbon flowing through the first heat medium line Lb.

In other words, in the indoor unit 2, the sensible heat of the water (heat medium) flowing through the second heat medium line Lc and the latent heat exchange of the chlorofluorocarbon flowing through the first heat medium line Lb (sensible heat-latent heat exchange) ).

The cold water discharged from the connection port 23 of the indoor unit 2 flows into the air conditioner 3 from the connection port 31 of the air conditioner 3, and the space in which the air conditioner is installed is stored in the cold room. The refrigerant (water) cools the indoor air in the air conditioner 3, and is sent from the connection port 32 to the connection port 24 of the indoor unit 2 via the line Lc2.

On the other hand, the low-pressure gas phase chlorofluorocarbon which has been vaporized in the indoor unit 2 is passed from the air compressor via the connection port 21 of the indoor unit 2, the line Lb2, the ports Vp2, Vp4 of the four-way valve V4, and the line Lb5. The suction port 4i of 4 is sucked in. Then, the air compressor 4 is compressed into a high-pressure gas phase chlorofluorocarbon and then discharged from the discharge port 4o.

In the case of the greenhouse operation shown in FIG. 3, even if the pump 5 is not operated, the CO ₂ flowing through the piping system La can be well circulated in the region including the region immersed in the water tank 150.

On the other hand, in the case of the operation of the cold room shown in FIG. 4, as described above, when the pump 5 is not operated, the CO ₂ flowing through the piping system La does not circulate in the piping system La.

Such a pump 5 and the lines La1, La4, and La5 will be described later with reference to Figs. 7 to 9 .

Here, in the outdoor room operation shown in FIG. 3 or the cold room operation shown in FIG. 4, in the outdoor unit 1, the CO ₂ flowing through the piping system La and the fluorine flowing through the first heat medium line Lb. Since chlorocarbon exchanges heat of vaporization heat and performs so-called "latent heat-latent heat exchange", a large amount of heat is exchanged, and efficiency is increased.

In Fig. 1, Fig. 3, and Fig. 4, the piping system La through which the heating medium flows in the water tank 150 is constituted by U-shaped tubes which are formed separately by reciprocating paths, but in the illustrated embodiment, The piping in the water tank 150 can also be constructed as a double pipe.

Such a double pipe will be described with reference to Figs. 5 to 12 .

In Fig. 5, the double tube 9 constituting the piping system La is composed of an inner tube 91 and an outer tube 92.

As shown in Fig. 5, in the warm room (see Fig. 3), the liquid phase CO ₂ sent from the outdoor unit 1 is lowered in the inner tube 91 of the double tube 9.

Since the specific gravity of the liquid phase CO ₂ is larger than that of the gas phase CO ₂ , it falls down due to its weight.

When the liquid phase CO ₂ is supplied to the heat of vaporization of water derived from the water tank 150, it is vaporized into a gas phase CO ₂ . Then, since the specific gravity of the gas phase CO ₂ is smaller than the specific gravity of the liquid phase CO ₂ , the outer tube 92 of the double tube 9 rises toward the outdoor unit 1.

That is, in the warm room of Fig. 3, the liquid phase CO _{2 to} be transported into the water W in the water tank 150 depends on the weight, and the inner tube 91 falls downward, and the gaseous CO which is returned from the water W in the water tank 150 _{Since the 2nd} system rises in the outer pipe 92, it is not necessary to supply the power for allowing the CO _{2 which} is a heat medium to flow in the double pipe 9 from the outside.

In the cold room described with reference to Fig. 4, as shown in Fig. 6, the gas phase CO ₂ sent from the outdoor unit 1 is lowered in the outer tube 92 of the double tube 9. Then, CO ₂ gas is put into the heat of vaporization of water W in the water tank 150 condenses into the liquid phase of the CO ₂ system for the outdoor unit 1 and the double-pipe inner pipe rises to 919.

Here, in the case of a cold room, unlike a warm room, power is required because the gas phase CO _{2 having a} small specific gravity is lowered to increase the liquid phase CO ₂ having a large specific gravity.

Therefore, as shown in Fig. 7, the first opening and closing valve Vb1 is provided at the bottom of the outer tube 92 of the double tube 9, and the pump 5 for circulating CO _{2 is} provided at the end.

Further, a second opening and closing valve Vb2 is attached to the lower end of the inner tube 91. Here, when the second opening/closing valve Vb2 is opened, the end of the inner tube 91 communicates with the outer tube 92, and when the second opening/closing valve Vb2 is closed, the end of the inner tube 91 is closed.

The discharge port of the pump 5 is connected to the vicinity of the bottom of the inner tube 91 in the line 93, and the third opening/closing valve Vb3 is interposed in the line 93.

In the case of a warm room, as shown in FIG. 8, the first opening and closing valve Vb1 and the third opening and closing valve Vb3 are closed, and the second opening and closing valve Vb2 is opened.

As described above, in the case of a warm room, the liquid phase CO _{2 which} descends from the inner tube 91 exchanges heat with the water W in the water tank 150, and is heated into vaporized CO ₂ . Then, the vapor phase CO ₂ flows into the vicinity of the bottom of the outer tube 92 via the second opening and closing valve Vb2, and rises from the bottom of the outer tube 92 to the outer tube 92. Here, even if the gas phase CO ₂ and the liquid phase CO _{2 are} mixed together to form a so-called "gas phase 2 phase flow" and flow into the outer tube 92, heat exchange with the water W in the water tank 150 is completed, and the gas phase CO is completely formed. ₂ and rise toward the outdoor unit 1 side.

Although not shown, the liquid phase CO ₂ does not vaporize in the water W in the water tank 150, and a mechanism (for example, a heating mechanism) that promotes vaporization may be provided.

In the cold room, as shown in FIG. 9, the second opening/closing valve Vb2 at the end of the inner tube 91 is closed, and the first opening/closing valve Vb1 and the third opening/closing valve Vb3 are opened to operate the pump 5.

By operating the pump 5, the negative pressure acts on the outer tube 92, so that the CO ₂ in the gas phase having a small specific gravity is lowered.

The gas phase CO ₂ system descending from the outer tube 92 is discharged while the inside of the water tank 150 is discharged and is condensed. Then, the liquid phase CO ₂ is attracted by the pump 5. The liquid phase CO ₂ discharged from the pump 5 is pressure-fed from the inner tube 91 to the outdoor unit 1 via the line 93 and the third opening and closing valve Vb3.

As described with reference to Figs. 5 to 9, the heat medium from the outdoor unit 1 and the heat medium entering the outdoor unit 1 flow through the inner tube 91 of the double tube 9 or flow through the double layer in the cold room and the warm room. The outer tube 92 of the tube 9 is not identical.

Fig. 10 is a view showing a schematic configuration of a pipe in an outdoor unit side end portion (upper end portion) of the double pipe 9.

In Fig. 10, the upper end of the inner tube 91 of the double tube 9 is connected to the line La2 shown in Figs. 1 to 3, and the upper end of the outer tube 92 is connected to the line La3 shown in Figs.

In addition, in the case of a cold room and a warm room, the flow direction of the CO ₂ flowing through the piping system La and the chlorofluorocarbon flowing through the first heat medium line Lb may be different from those shown in FIGS. 1 to 3 .

In order to cope with such a situation, as shown in FIG. 11, it is also possible to construct four valves Va1 to Va4 on the piping system La side, and the line La2 and the line La3 can communicate with either the inner tube 92 or the outer tube 93.

In FIG. 11, the line La2 that communicates with the connection port 11 of the outdoor unit 1 and the line La3 that communicates with the connection port 12 of the outdoor unit 1 communicate with the outer tube 92. The opening and closing valve Va1 is interposed in the line La2, and the opening and closing valve Va2 is interposed in the line La3.

The line La6 is branched from the branch point Ba2 of the line La2 and communicates with the inner tube 91. Further, the line La7 is branched from the branch point Ba3 of the line La3 and communicates with the inner tube 91.

An opening and closing valve Va3 is interposed in the line La6, and an opening and closing valve Va4 is interposed in the line La7.

A first modification of the double tube 9 described with reference to Figs. 5 to 11 is shown in Fig. 12 .

In the first modification of FIG. 12, the outer tube 92A of the double tube 9A is formed with irregularities in the longitudinal direction (the center line CL direction). The surface area is increased by forming such irregularities to improve heat exchange efficiency.

Although not shown, the inner tube 91A of the double tube 9A may have irregularities formed in the longitudinal direction.

Fig. 13 shows a second modification of the double tube 9.

In the second modification of Fig. 13, the outer tube 92B of the double tube 9B is provided with irregularities in the circumferential direction, thereby increasing the surface area to improve the heat exchange efficiency.

In the second modification described above, although not shown, irregularities in the circumferential direction may be formed in the inner tube 91B of the double tube 9B.

Further, as a modification of the double tube 9, although not shown, a heat sink may be provided in the outer tube (or the outer tube and the inner tube) of the double tube.

According to the first embodiment, CO _{2 is} used as a heat medium, and heat of vaporization (condensation heat) of CO ₂ is transmitted through heat exchange with water in the water tank 150 to be introduced into the heat medium, or water from the heat medium to the water tank 150 is used. discharge. Then, the so-called "latent heat-sensible heat exchange" is performed by the latent heat of the CO ₂ heat medium and the sensible heat of the water W in the water tank 150.

Here, the "latent heat-sensible heat exchange" and the "latent heat-sensible heat exchange" can recover or discharge a large amount of heat per unit amount of the heat medium, so that the heat efficiency becomes good.

Further, the CO _{2 is} larger in heat capacity than the brine used in the prior art.

Therefore, according to the first embodiment, the heat medium can efficiently collect the heat retained by the water in the water tank 150, or can efficiently discharge the heat into the water W in the water tank 150, so that it can be immersed in the water tank. The piping system La (double pipe 9) in the water W in 150 is made short and thin.

Therefore, when the piping system La (double pipe 9) is immersed in the water W in the water tank 150, it is not necessary to dig into a deep area in the ground, and it is not necessary to embed a large space for piping.

In the case of using a conventional geothermal technique using a brine of a liquid phase as a heat medium, it is necessary to arrange the piping system for circulating the liquid phase brine along the foundation pile, or to arrange the ground in the foundation pile. Piping, when the foundation pile is constructed, will incur additional costs.

Further, when the piping in the ground in which the brine is supplied is not disposed in the vicinity of the pile, it is necessary to dig the well for piping in the ground to a deeper portion of the ground, resulting in a required cost.

According to the first embodiment, the piping system La (double pipe 9) in the water W immersed in the water tank 150 can be made short and thin, so that the above-described cost does not occur.

In the first embodiment, the pipe system La which is immersed in the water W in the water tank 150 is constituted by the double pipe 9.

As described above, in the operation of the greenhouse, the liquid phase CO _{2 is} lowered in the inner tube 91 of the double tube 9, and the heat (gasification heat) retained by the water in the water tank 150 is supplied and vaporized. The phase CO ₂ rises in the outer tube 92 of the double tube 9, so that the CO ₂ belonging to the heat medium does not require external power when circulating in the piping system La.

Therefore, the running cost in the greenhouse can be reduced.

Fig. 14 shows the control in the first embodiment.

According to the research and experiments of the inventors, it is clearly understood that if the temperature of the heat medium (CO ₂ ) in the piping system exposed from the water tank 150 is 5 ° C to 40 ° C, the efficiency of the greenhouse or the efficiency of the cold room can be improved most.

The temperature of the carbon dioxide flowing in the area exposed to the water storage device is higher than 40 ° C, and the heat exchange efficiency is lowered in the cold room. On the other hand, the temperature of the carbon dioxide flowing in the region exposed to the water storage device is lower than 5 ° C, and the pressure of the heat medium in the piping system La becomes a low pressure, and the carbon dioxide of the heat medium is naturally circulated. It is difficult for carbon dioxide to circulate in the piping system La.

The temperature of the CO ₂ in the water W sent from the outdoor unit 1 to the water tank 150 depends on the temperature (pressure) of the CO ₂ at the time point and the amount of the heat medium CO ₂ in the entire system.

Therefore, in FIG. 14, the temperature (pressure) of CO ₂ in the water W sent from the outdoor unit 1 to the water tank 150 is displayed, and the temperature of the heat medium (CO ₂ ) in the piping system exposed from the water tank 150 can be set. The method of controlling the amount of CO ₂ in the entire system by the method of 5 ° C to 40 ° C.

In FIG. 14, the amount of CO ₂ is subjected to an opening degree of a flow rate adjustment valve Vc that is interposed in an inflow path (CO ₂ supply line) Lc from the CO ₂ supply source 10, and a pipe that is interposed in the water tank 150. It is controlled by the opening degree of the discharge valve Va of the discharge system Le of La9 (having the function as a flow regulating valve).

In FIG. 14, the piping system La9 in the outdoor unit 1 and the water tank 150 is closed by a piping La (La20, La30).

Further, in Fig. 14, the CO ₂ piping system La9 soaked in the water of the water tank 150 is not a double tube but a single tube, and is a U-shaped tube.

In Fig. 14, the pipe La is constituted by a line La20 and a line La30. Further, the line La20 connects the connection portion Pa2 to the connection port 11 of the outdoor unit 1, and the line La30 connects the connection port 12 of the outdoor unit 1 and the connection portion Pa3. In other words, the pipe La20 and the pipe La9 are connected to the connection portion Pa2, and the pipe La9 and the pipe La30 are connected to the connection portion Pa3.

The line La20 is provided with a drain valve Va (flow regulating valve).

And, in line La20, in the region between the valve Va and the outdoor unit 1 is connected to drain CO ₂ feeder line Lc, Lc CO ₂ feeder line based on communication with source 10 CO ₂ feeder.

The CO ₂ supply line Lc is provided with a CO ₂ supply amount adjustment valve Vc, and controls the opening degree of the CO ₂ supply amount adjustment valve Vc to adjust the supply amount of CO ₂ circulating in the piping system 9a.

In the line La20, a temperature sensor 6 (or a pressure sensor 40) is interposed in a region between the discharge valve Va and the connection portion Pa2 in the pipe La9.

Here, FIG. 14, the temperature sensor 6 (or a pressure sensor 40) is connected to the line, although LA20, but the actual device, is interposed in the line and line LA20 La30 heat medium in the case of CO ₂ will The line on the side from the outdoor unit 1.

In addition, it is assumed that when the greenhouse operation and the cold room operation are to switch the line in which the CO ₂ of the heat medium flows into the side of the outdoor unit 1, the temperature sensor 6 (or the pressure sensor 4) is disposed in the line La20 and Both of the lines La30 are preferred.

In Fig. 14, a control unit 50A that is a control means is provided.

The control unit 50A is connected to the temperature sensor 6 and the pressure sensor 40 via an input signal line Si.

Further, the control unit 50A is connected to the discharge valve Va and the CO ₂ supply amount adjustment valve Vc via the control signal line So.

Next, referring mainly to Fig. 15, and referring to Fig. 14 together, the control of the supply amount of CO ₂ will be described.

In Fig. 15, in step S11, the temperature of the CO ₂ flowing through the line La20 (for example, liquid CO ₂ if it is a greenhouse) is measured by the temperature sensor 6, or the flow is measured by the pressure sensor 40. The CO ₂ pressure of La20 (step S12).

In step S13, the control unit 50A determines the opening degree of the bleed valve (flow rate adjusting valve) Va.

Although not explicitly shown, the control unit 50A within the predetermined characteristic of the memory, i.e., in the flow (or pressure ₂ CO) lines La20 and the temperature of CO ₂ to the outdoor unit 1 from the water tank 150 of the water The temperature of the heat medium is a relationship (characteristic) of the amount of the heat medium CO ₂ (hereinafter referred to as "predetermined heat medium amount") at a predetermined temperature.

In addition, the control unit 50A has a valve opening degree from the discharge valve Va and the CO ₂ supply amount adjustment valve Vc at the time point, and obtains the amount of CO ₂ circulating in the piping system 9a at the time point (hereinafter, the description The function of "CO ₂ circulation").

Further, the control unit 50A has a valve opening degree at which the amount of CO ₂ circulation at its time point is compared with the valve opening degree of the bleed valve Va and the CO ₂ supply amount adjusting valve Vc for setting the predetermined amount of heat medium at the time point thereof. The function of the valve opening degree of the discharge valve Va and the CO ₂ supply amount regulating valve Vc is determined.

In the next step S14, the control unit 50A obtains the CO ₂ circulation amount from the valve opening degree of the discharge valve Va and the CO ₂ supply amount adjustment valve Vc at the time point, and compares it with the predetermined heat medium amount. Determine if it is appropriate.

When the amount of the CO ₂ circulation is appropriate (YES in the step S14), the valve opening degree of the discharge valve Va and the CO ₂ supply amount adjustment valve Vc is maintained as it is (step S15), and the flow proceeds to step S18.

When the CO ₂ circulation amount is excessively large (step S14 is "large"), the valve opening degree of the CO ₂ supply amount adjustment valve Vc is decreased, and/or the valve opening degree of the discharge valve Va is increased (step S16). Then it proceeds to step S18.

When the CO ₂ circulation amount is too small (step S14 is "small"), the valve opening degree of the CO ₂ supply amount adjustment valve Vc is increased, and/or the valve opening degree of the discharge valve Va is decreased (step S17). Then it proceeds to step S18.

At step S18, it is judged whether or not the operation of the system is to be ended.

If the operation of the system is to be completed (YES in step S18), the control is ended.

If the system operation is continued (NO in step S18), the process returns to step S11, and the steps from step S11 onwards are repeated.

The other configurations and operational effects in Figs. 14 and 15 are the same as those described with reference to Figs. 1 to 13 .

In the first embodiment, the temperature of the carbon dioxide flowing in the region where the piping system La enters the water tank 150 when the cold room operation is performed will be described with reference to the experimental example (see Fig. 26(A) and Fig. 28). The temperature indicated by "O" in the middle: the temperature measured by the temperature sensor 7 in Fig. 4) and the temperature of the water in the water tank 150 (Fig. 26(A), the temperature indicated by the characteristic curve of the broken line in Fig. 28; The temperature difference of the temperature measured by the temperature sensor TW1 in 4 is set to 60 ° C or less.

On the other hand, in the case of performing the greenhouse operation, the water temperature in the water tank 150 (the temperature indicated by the characteristic curve of the broken line in Fig. 27(A): the temperature measured by the temperature sensor TW1 in Fig. 3) is The temperature difference of the temperature of the carbon dioxide (the temperature indicated by "O" in Fig. 27(A); the temperature measured by the temperature sensor 6 in Fig. 3) in the area of the piping system La to be flowed into the water tank 150 is set. It is below 30 °C.

Here, as described with reference to FIGS. 14 and 15, the temperature of the CO ₂ sent from the outdoor unit 1 to the water tank 150 is shown in FIG. 26(A), FIG. 27(A), and FIG. The temperature is dependent on the temperature (pressure) of CO ₂ at its point in time and the amount of heat medium CO ₂ in the system as a whole.

Therefore, in order to control the temperature of the water in the water tank 1 (the temperature measured by the temperature sensor TW1) and the temperature of the CO ₂ flowing in the area of the pipe La to enter the water tank 1 (the temperature sensors 6, 7 are in the piping La) The temperature difference of the temperature to be measured in the area on the side of the water tank 1 may be adjusted by adjusting the amount of CO ₂ in the entire system 100.

In the first embodiment, when the cold room operation is to be performed, the temperature difference between the temperature of the carbon dioxide flowing in the region where the piping system La is to enter the water tank 150 and the water temperature in the water tank 150 is set to 60 ° C or lower. In the case of the operation of the greenhouse, the temperature difference between the temperature of the water in the water tank 150 and the temperature of the carbon dioxide flowing through the area of the piping system La to be entered into the water tank 150 is set to 30 ° C or less, and the CO ₂ of the entire system 100 is adjusted. The control of the amount will be described with reference to Figs. 29 and 30.

FIG 29, for the adjustment system 100 as a whole the amount of CO _{2 while} the control ₂ is supplied amount of CO from a CO ₂ supply source 10 and via the amount of CO ₂ is connected to the piping La of the discharge system Le discharged (CO ₂ emission) Just fine.

In addition, in order to control the supply amount of the CO ₂ from the CO ₂ supply source, for example, the flow rate adjustment valve Vc may be disposed in the piping system that connects the CO ₂ supply source and the piping La, and the valve opening degree of the flow rate adjustment valve may be controlled. Moreover, in order to control the CO ₂ discharge amount, for example, the discharge valve Va may be provided in the discharge system Le to control the valve opening degree of the discharge valve.

In other words, during the operation of the cold room, the temperature of the carbon dioxide flowing through the region La30 of the piping system La to enter the water tank 150 is measured by the temperature sensor 7 (shown as "O" in Fig. 26(A) and Fig. 28). Temperature), the temperature of the water in the water tank 150 is measured by the temperature sensor TW1 (the temperature indicated by the characteristic curve of the broken line in FIG. 26(A) and FIG. 28), and the measurement results of the temperature sensor 7 and TW1 are sent. The control unit 50B adjusts the CO ₂ supply so that the temperature difference in the measurement results of the temperature sensors 7 and TW1 can be 60° C. or less, based on the characteristic map, the characteristic formula, the graph, and the like stored in the control unit 50B. Amount and CO ₂ emission.

On the other hand, during the operation of the greenhouse, the temperature of the water in the water tank 150 is measured by the temperature sensor TW1 (the temperature indicated by the characteristic curve of the broken line in FIG. 27(A)), and the temperature sensor 6 measures the piping system La. The temperature of the carbon dioxide flowing through the area La20 entering the water tank 150 (the temperature indicated by "O" is plotted in FIG. 27(A)), and the measurement results of the temperature sensors TW1, 6 are sent to the control unit 50B. The temperature difference between the measurement results of the temperature sensors 6 and TW1 can be 30° C. or less, and the CO ₂ supply amount and CO ₂ emission can be adjusted by the characteristic map, the characteristic formula, the graph, and the like stored in the control unit 50B. the amount.

For the supply amount of CO ₂ emission amount of CO ₂ and adjusted, mainly based on FIG. 30 and described with reference made to FIG 29.

In step S11A in FIG. 30, the temperature of the CO ₂ or the water temperature in the water tank 150 is measured by the temperature sensors 7 and TW1 during the operation of the cold room, and the water temperature is measured by the temperature sensors TW1 and 6 during the operation of the greenhouse. Water temperature or CO ₂ temperature within 150.

Next, in step S13A, the temperature difference of the temperature measured by the temperature sensor 7 and TW1 is used in the operation of the cold room, and the temperature difference of the temperature measured by the temperature sensors TW1, 6 is used during the operation of the greenhouse, and the control is utilized. The unit 50B determines the amount of CO ₂ of the entire system 100, or the valve opening degree of the discharge valve Va and the CO ₂ supply amount adjustment valve Vc. At the same time, the control unit 50B determines the overall opening of the system 100 at its time point (control period) from the valve opening degree of the discharge valve Va and the CO ₂ supply amount adjustment valve Vc at its time point (control cycle). The amount of CO ₂ (hereinafter referred to as "CO ₂ circulation amount").

In step S14A, the control unit 50B sets the amount of CO ₂ circulation at the time point and the prescribed CO ₂ circulation amount (the temperature difference of 60 ° C or less in the cold room and 30 ° C or less in the greenhouse) to the time point ( The CO ₂ cycle amount of the control cycle is compared.

When the amount of the CO ₂ circulation is appropriate (YES in the step S14A), the valve opening degree of the discharge valve Va and the CO ₂ supply amount adjustment valve Vc is maintained as it is (step S15A), and the flow proceeds to step S18A.

When the CO ₂ circulation amount is excessively large (step S14A is "large"), the valve opening degree of the CO ₂ supply amount adjustment valve Vc is decreased, and/or the valve opening degree of the discharge valve Va is increased (step S16A). Then it proceeds to step S18A.

When the CO ₂ circulation amount is too small (step S14A is "small"), the valve opening degree of the CO ₂ supply amount adjustment valve Vc is increased, and/or the valve opening degree of the discharge valve Va is decreased (step S17A). Then it proceeds to step S18A.

Next, in step S18, it is determined whether or not the operation of the system is to be completed. If the operation is completed, the operation of the system is terminated (NO in step S18), and the steps from step S11 onwards are repeated.

By adjusting the CO ₂ circulation amount of the system 100 by the control described with reference to FIGS. 29 and 30, the temperature difference can be maintained (60° C. or lower in the cold room and 30° C. or lower in the greenhouse).

The other configurations and operational effects in Figs. 29 and 30 are the same as those described with reference to Figs. 1 to 15 .

Fig. 16 is a view showing a modification of the first embodiment.

In the first heat medium line Lb, an air-conditioning load (a second heat medium line Lc through which the air conditioner 3 is interposed) is connected (thermally) to the first heat medium line Lb via the indoor unit 2 .

In contrast, in FIG. 16, the hot water supply load 8 as a heat load is also connected (thermally) to the first heat medium line Lb.

In Fig. 16, a hot water supply load (e.g., water heater) 8 is interposed between the port Vp2 of the four-way valve V4 connected to the first heat medium line Lb and the line Lb2 of the connection port 21 of the indoor unit 2.

The hot water supply of the water heater 8 is performed by the same warm room operation as the warm room operation of the first embodiment described with reference to Fig. 3 .

Further, although not shown, the air conditioning load may be omitted, and only the hot water supply load 8 may be provided.

The other configurations and operational effects of the modification of Fig. 16 are the same as those of the embodiment of Figs. 1 to 15 .

In addition, although not shown, the four-way valve V4 and the lines La1 and La4 and the pump 5 in the water tank 150 are omitted, and the first embodiment of FIGS. 1 to 15 can be used as a system for performing only a greenhouse operation.

Even in that case, as in the modification of Fig. 16, the hot water supply load and the air conditioning load may be provided in combination, or only the hot water supply load may be provided.

Fig. 17 is a view showing a second embodiment of the present invention.

In the first embodiment, the CO ₂ pipe for heat exchange between the water W in the water tank 150 and the heat of vaporization (or condensation heat) of the CO ₂ of the heat medium is provided as a single system.

However, in the second embodiment of Fig. 17, the CO ₂ pipes are branched and a double system is provided, and in each of the dual systems, the heat of vaporization (or condensation heat) of the CO ₂ belonging to the heat medium and the water in the water tank 150 are created. The heat retained can be exchanged for heat.

In Fig. 17, the CO ₂ pipe La circulating in the outdoor unit 1 is connected to the double pipe 9C in the vicinity of the upper edge of the water tank 150. A three-way valve V30 is interposed at the lower end of the double tube 9C. Double-layer pipes 9D and 9D of the same specification are connected to each other in three-way valve V30. Further, the double tubes 9D and 9D of the same specification are each immersed in the water W of the water tank 150. The double tube 9D self-system is the same as that shown in Figs. 5 to 13 .

Here, in Fig. 17, the heat of the CO ₂ flowing through the double tube 9D does not affect each other, or the CO ₂ flowing through the double tube 9D does not exchange heat with each other (CO flowing through the double tube 9D) _{2, the} mutual thermal interference), the distance between the different pipes 9D, 9D, at least 1m apart.

According to the second embodiment described above, since the piping system 9D immersed in the water W of the water tank 150 is provided in a plurality of systems, the heat retained by the water of the water tank 150 can be efficiently recovered, or the heat can be directed toward the water tank 150. The water W is discharged.

The other configurations and operational effects of the second embodiment of Fig. 17 are the same as those of the first embodiment of Figs. 1 to 16 .

18 to 21 show a third embodiment of the present invention.

In the embodiment of FIGS. 1 to 17, the CO ₂ pipe is immersed in the water W in the water tank 150. However, in the third embodiment of FIGS. 18 to 21, the CO ₂ pipe system is immersed in the water reservoir GH.

In Fig. 18, the CO ₂ piping system La is connected to a spiral double tube 9E. However, a linear double tube 9C may be interposed, and the piping system La may be connected to the spiral double tube 9E.

In order to allow the double tube 9E of the CO ₂ piping system to be spirally immersed in the reservoir GH, the CO ₂ piping (double tube 9E) can be formed of a material having good flexibility. Then, it is inserted into the reservoir GH in a spiral form and configured.

Alternatively, the shape memory alloy is used to form a CO ₂ pipe (double pipe 9E), and the shape memory alloy is stored in a spiral shape as shown in FIG. 18 when the temperature in the water in the reservoir GH is 5 to 40 ° C. And it can be configured in a spiral form toward the reservoir GH.

According to the third embodiment of Figs. 18 to 21, since the piping system 9E is arranged in a spiral shape in the reservoir GH, the circumferential length is three times the diameter, and the heat exchange between CO ₂ and water is sufficiently ensured. The state of the length can reduce the depth direction of the reservoir GH to about 1/3 of the conventional one.

In addition, as a result of the reduction in the depth direction of the reservoir GH, the cost required for system construction is further saved.

Here, in order not to cause piping system flows through the spiral-shaped portions within the 9E CO ₂ to each other by heat exchange (heat flow in a helical pipe line portions within the 9E CO ₂ affect each other), a spiral of It is preferable that the pitch and the diameter are 1 m or more.

19 to 21 show the construction procedure of the third embodiment.

In the construction of the third embodiment of Figs. 19 to 21, first, as shown in Fig. 19, the vertical pit is excavated in the soil G, and the inner wall surface of the excavated vertical pit is covered with a reinforcing material or the like to prevent the soil from collapsing. The reservoir GH for arranging the piping system 9E is created. Then, as shown in FIG. 20, a spiral piping system 9E is disposed in the reservoir GH.

Here, it is preferable that the pitch and the diameter in the spiral piping system 9E are 1 m or more and as small as possible. Because if the pitch and diameter of 1m or less, will result in various parts of the circulation in the spiral piping system 9E CO ₂ by heat exchange (heat flowing through the spiral pipe line portions within the 9E CO ₂ mutually For the sake of mutual influence, and when the pitch and diameter of the spiral piping system 9E are large, the diameter and depth of the reservoir GH must be large.

After the spiral piping system 9E is disposed in the reservoir GH, as shown in FIG. 21, the water W is filled in the reservoir GH.

Here, the water W may be ground water. The temperature level of groundwater is the same as that of soil G.

The other configurations and operational effects of the third embodiment of Figs. 18 to 21 are the same as those of the respective embodiments of Figs. 1 to 17 .

Fig. 22 is a view showing a fourth embodiment of the present invention.

The fourth embodiment of Fig. 22 corresponds to the combination of the second embodiment of Fig. 17 and the third embodiment of Figs. 18 to 21 .

In Fig. 22, the CO ₂ pipe La circulating in the indoor unit 1 is connected to the double pipe 9C. Further, a three-way valve V30 is interposed at the lower end of the double pipe 9C.

A double tube 9D soaked in water and a spiral double tube 9E are connected to each other from the three-way valve V30.

The configuration of the double pipe 9D is the same as that described in Figs. 5 to 13 of the first embodiment, and is used in the same manner as the double pipe 9C. On the other hand, the spiral double tube 9E is the same as the spiral double tube 9E of the third embodiment shown in Figs. 18 to 21 .

According to the fourth embodiment of Fig. 22, the amount of heat retained by the water in the water tank 150 can be more efficiently recovered than in the respective embodiments of Figs. 17 to 21 .

The other configurations and operational effects of the fourth embodiment of Fig. 22 are the same as those of the respective embodiments of Figs. 1 to 21 .

Fig. 23 is a view showing a fifth embodiment of the present invention.

In the embodiment of Fig. 23, compared with the fourth embodiment of Fig. 22, the double tubes which are branched from the three-way valve 3V are all spiral double tubes 9E.

Here, in a manner in which the spiral double tube (CO ₂ pipe) 9E does not interfere with each other, the closest portion is required to be at least 1 m apart.

According to the fifth embodiment of Fig. 23, the amount of heat retained by the water in the water tank 150 can be recovered more efficiently than in the fourth embodiment of Fig. 22 .

The other configurations and operational effects of the fifth embodiment of Fig. 23 are the same as those of the respective embodiments of Figs. 1 to 22 .

Fig. 24 is a view showing a sixth embodiment of the present invention.

In the sixth embodiment of Fig. 24, as in the fifth embodiment of Fig. 23, the double tubes that are branched from the three-way valve 3V are all arranged in a spiral shape, but one of the spiral double tubes 9F is arranged in the same manner. The other spiral double tube 9E is surrounded outward in the radial direction of the other spiral double tube 9E (same as the double tube 9E of Fig. 23).

In this case, the spiral double-layer pipes (CO ₂ pipes) 9E and 9F are not thermally interfered with each other, so that the spiral double-layer pipes (CO ₂ pipes) 9E and 9F are at least 1 m apart in the diameter direction. .

In addition, the two spiral double tubes 9E, 9F each need to be separated by at least 1 m in the up and down direction (the pitch direction of the spiral).

According to the sixth embodiment of Fig. 24, compared with the fifth embodiment of Fig. 23, it is possible to reduce the horizontal space of the double tubes 9E and 9F for arranging the divergence, and even if it is immersed in water. The length of the tube 9F is short, and the amount of heat retained by the water in the water tank 150 can be maintained or increased.

The other configurations and operational effects of the sixth embodiment of Fig. 24 are the same as those of the respective embodiments of Figs. 1 to 23 .

[Experimental example]

Next, an experimental example of the present invention will be described with reference to Figs. 25 to 28 .

Fig. 25 is a view showing an outline of an experimental apparatus used in the experimental example.

In Fig. 25, the experimental apparatus indicated by the whole symbol 500 is provided with the first water tank 150, the heat pump HP, the second water tank 200, the piping system LaE that communicates with the first water tank 150 and the heat pump HP, and the heat pump HP and the 2 The piping of the water tank 200 is LcE.

The second water tank 200 is provided as a heat load corresponding to the air conditioner (including the warm water floor heating device or the like) 3 shown in FIG. 1 and the like. That is, the second water tank 200 represents a heat load.

Further, the heat pump HP in Fig. 25 corresponds to a compression type air conditioner having an outdoor unit 1, an indoor unit 2, an air compressor 4, a pressure reducing valve V3, and a four-way valve V4 in Fig. 1 and the like.

In the piping system LaE, CO ₂ which is a heat medium flows, and in the piping system (see arrow Fa) from the heat pump HP toward the first water tank 150, temperature sensing for measuring the temperature of the CO ₂ flowing therein is introduced. T _S 1. The temperature measured by the temperature sensor T _S 1 is indicated by "O" in FIGS. 26(A), 27(A), and 28 .

A temperature sensor Ts2 for measuring the temperature of the CO ₂ flowing therein is disposed in a piping system (see an arrow Fb) that faces the heat pump HP from the first water tank 150. The temperature measured by the temperature sensor Ts2 is indicated by "△" in FIGS. 26(A), 27(A), and 28.

A temperature sensor Ts3 for measuring the water temperature of the water stored therein is provided in the first water tank 150. The water temperature in the water tank 150 measured by the temperature sensor Ts3 is indicated by a characteristic line indicated by a broken line in FIGS. 26(A), 27(A) and 28.

Further, a heat medium (for example, water) flows through the piping system LeE, and a piping system (see arrow Fc) from the heat pump HP toward the second water tank 200 is provided with a heat medium (water) for measuring the circulation therein. The temperature of the temperature sensor Ts4. The temperature measured by the temperature sensor Ts4 is indicated by "O" in Figs. 26(B) and 27(B).

A temperature sensor Ts5 for measuring the temperature of the heat medium (water) flowing therethrough is interposed in a piping system (see an arrow Fd) from the second water tank 200 toward the heat pump HP. The temperature measured by the temperature sensor Ts5 is indicated by "△" in Figs. 26(B) and 27(B).

In the experimental example, the experimental apparatus shown in Fig. 25 was operated, and the temperature measured by the temperature sensors Ts1 to Ts5 was obtained, and the characteristics of the elapsed time from the start of the operation of the experimental apparatus and the measured temperature were obtained.

In Figs. 26(A) to (C), Figs. 27(A) to (C), and Fig. 28, the characteristic curve of the elapsed time-temperature characteristic is shown.

Figure 26 shows the experimental results regarding the operation of the cold room.

26(A) shows the temperature characteristics of the CO ₂ from the heat pump HP and directed toward the first water tank 150 (time characteristic of the measurement result of the temperature sensor Ts1: "O" is plotted), and is discharged from the first water tank 150. Temperature characteristic of CO ₂ toward heat pump HP (time characteristic of measurement result of temperature sensor Ts2: plot "△"), condensation temperature of CO ₂ (characteristic shown by thick solid line), critical point of CO ₂ ( The characteristic shown by the thin solid line) and the temperature characteristic in the water tank 150 (time characteristic of the result measured by the temperature sensor Ts3: characteristic shown by a broken line).

26(B) shows the temperature characteristics of the heat medium (water) from the heat pump HP toward the second water tank 200 (time characteristic of the measurement result of the temperature sensor Ts4: plot "O") and return from the second water tank 200 The temperature characteristic of the heat medium (water) of the heat pump HP (time characteristic of the measurement result of the temperature sensor Ts5: "△" is plotted).

26(C) shows the temperature of the heat medium (water) from the heat pump HP to the second water tank 200 in FIG. 26(B) (the measurement result of the temperature sensor Ts4: "O" is plotted) and the second water tank The characteristic of the temperature difference of the temperature of the heat medium (water) of the heat pump HP (measured by the temperature sensor Ts5: "△") is the characteristic of the heat or cooling capacity of the second water tank 200.

Figure 27 shows the experimental results regarding the operation of the greenhouse.

The characteristic curves of Figs. 27(A) and (B) are the same as those of Figs. 26(A) and (B).

Fig. 27(C) shows the characteristics of the greenhouse capacity.

In Fig. 26(C) showing the operation of the cold room, in the area where the elapsed time (horizontal axis) is 2 minutes, the cold room capacity (vertical axis) is very high (22 to 23 kW).

Although it is not shown in FIG. 26(C), when a tube having a diameter of 3 inches and a length of 50 m is buried in the ground to exchange heat with geothermal heat, the cold room capacity is measured under the same conditions as the experimental example, and the cold room is used. The capacity is 5kW. If compared with this value, it can be understood that the cold room capacity available in the experimental example is very high.

In the same manner, in FIG. 27(C) showing the operation of the greenhouse, the room capacity (vertical axis) rises to a high value in the region where the elapsed time (horizontal axis) is more than 30 minutes.

Although it is not shown in FIG. 27(C), in the experiment of the inventor, when a tube having a diameter of 3 inches and a length of 50 m was buried in the ground to exchange heat with geothermal heat, the same conditions as in the experimental example were measured. In the case of the capacity of the greenhouse, the capacity of the greenhouse is 5kW.

In Fig. 27(C), in the vicinity of the greenhouse capacity in the region where the elapsed time (horizontal axis) is more than 30 minutes, the capacity of the greenhouse is significantly improved as compared with the case where the heat exchange with the geothermal heat is performed.

At a stage before and after 30 minutes, the temperature of the CO ₂ flowing in the water tank 150 is raised to the vicinity of the critical point, and the heat exchange efficiency is improved by the increase in the specific heat of the CO ₂ , so that the capacity of the greenhouse is also estimated to be improved.

As is clear from Fig. 26(C) and Fig. 27(C), according to the present invention, the heat exchange efficiency is improved, and as a result, the cold room capacity and the warm room capacity are improved.

In Fig. 26(C) showing the operation of the cold room, it can be seen that the cold room capacity tends to decrease after about 22 minutes from the start of the operation of the experimental apparatus. Then, after 54 minutes, the capacity of the cold room dropped sharply.

When the temperature of the CO ₂ flowing through the water tank 150 is higher than the critical point temperature, the temperature of the CO ₂ is reduced, and the specific heat of CO ₂ is reduced, and the heat exchange efficiency is estimated to be lowered. Further, it is estimated that the temperature of the CO ₂ flowing through the water tank 150 is further increased after 54 minutes from the start of the operation of the experimental apparatus, and the specific heat is remarkably reduced.

In the experimental apparatus shown in FIG. 25, although the temperature of the CO can not be detected in the circulation of the water tank _1502, but it is clear, when the temperature (plot 'O') of the inflow of CO ₂ tank 150 and from tank 150 flows When the temperature of the CO ₂ (plot "Δ") is higher than the critical point temperature (the thin solid line of Fig. 26 (A)), the heat exchange efficiency is lowered, and the cold room capacity is also lowered.

On the other hand, in Fig. 27(A) showing the operation of the greenhouse, even after 60 minutes, the temperature of the CO ₂ flowing into the water tank 150 (plot "O") and the temperature of the CO ₂ flowing out of the water tank 150 (plotting) "△") does not separate from the critical point temperature (thin solid line in Fig. 27(A)). Accordingly, the temperature of the flow in the water tank appreciated 150 CO ₂ also does not deviate from the critical temperature.

For this reason, in Fig. 27(C), the heat exchange efficiency of CO ₂ is not lowered, and it is estimated that the greenhouse capacity maintains high efficiency even after 60 minutes.

As can be clearly seen from Fig. 26 and Fig. 27, when the temperature of the CO ₂ flowing out from the water tank 150 (plotted "Δ") is 40 ° C or less, the cold room capacity and the greenhouse capacity in the experimental apparatus are not lowered.

Although not shown, the inflow temperature of the water tank 150 CO.'S ₂ and the outflow of the water tank 150 from the temperature of CO ₂ compared to the case where the critical temperature is too low (less. 5 deg.] C), from 25 using the experimental apparatus shown in the FIG. Experiments show that in the case of CO ₂ natural circulation, the capacity of cold rooms and the capacity of greenhouses will decrease.

It is presumed that the pressure of the heat medium in the piping system LaE is lowered, and the circulation efficiency of the heat medium (CO ₂ ) in the piping system LaE is lowered.

Fig. 28 is a view showing the experiment at the time of operation of the cold room and the experimental results different from the operating conditions of Fig. 26. In other words, Fig. 28 is a characteristic diagram similar to Fig. 26(A).

As shown in Fig. 28, during the operation of the cold room, the temperature difference Δ between the water temperature in the water tank 150 (indicated by a broken line in Fig. 28) and the temperature of the CO ₂ flowing into the water tank 150 (plot "O") becomes Below 60 °C.

Although not explicitly shown in Fig. 28, according to experiments by the inventors, the temperature of the water in the water tank 150 (indicated by the characteristic curve of the broken line in Fig. 28) and the temperature of the CO ₂ flowing into the water tank 150 during the operation of the cold room were confirmed. When the temperature difference Δ of "O" is more than 60 °C, the capacity of the greenhouse is lowered.

As a result, it was confirmed that the temperature of CO _{2 to be} distributed in the area where the water storage equipment (150, GH) enters the piping system (La, 9) when performing the cold room operation (in Fig. 26(A), In Fig. 28, the temperature indicated by "O" is plotted: the temperature measured by the temperature sensor 7 in Fig. 4) and the water temperature in the water storage device (150, GH) (Fig. 26(A), Fig. 28 is dotted line The temperature difference indicated by the characteristic curve: the temperature measured by the temperature sensor TW1 in Fig. 4 is set to 60 ° C or lower.

In Fig. 27(A), during the operation of the greenhouse, the temperature of the water in the water tank 150 (indicated by the characteristic curve of the broken line in Fig. 27(A)) and the temperature of the CO ₂ flowing into the water tank 150 (plotted "O") The temperature difference Δ is 30 ° C or less.

Although not explicitly shown in Fig. 27, according to experiments by the inventors, it was confirmed that the water temperature in the water tank 150 (indicated by the characteristic curve of the broken line in Fig. 27(A)) and the CO ₂ flowing into the water tank 150 during the operation of the greenhouse. When the temperature difference Δ (see Fig. 27(A)) of the temperature (plotted "O") exceeds 30 °C, the greenhouse capacity is lowered.

As a result, in the case of the greenhouse operation, the water temperature in the water storage device (150, GH) (the temperature indicated by the characteristic curve of the broken line in Fig. 27(A): the temperature measured by the temperature sensor TW1 in Fig. 3 The temperature of CO ₂ flowing in the area of the piping system (La, 9) to be entered into the water storage device (150, GH) (the temperature indicated by "O" in Fig. 27(A): Fig. 3 The temperature difference of the temperature measured by the temperature sensor 6 should be 30 ° C or less.

It is to be noted that the illustrated embodiments are merely illustrative and are not intended to limit the scope of the technical scope of the invention.

In the illustrated embodiment, the water storage device is exemplified as the water tank 150 or the water storage tank GH. However, the water storage device may be an culvert or a ditch having a water depth to which the piping system through which the heat medium flows can be immersed ( Or open channel).

1. . . 1st heat exchanger / outdoor unit

1h, 2h. . . Heat exchange department

2. . . 2nd heat exchanger / indoor unit

3. . . air conditioner

4‧‧‧Air compressor

4i, 5i‧‧ ‧ suction inlet

4o, 5o‧‧‧ spitting

5‧‧‧ pump

6, 7‧‧‧ Temperature Sensor

8‧‧‧Water heater

9‧‧‧ Double tube

10‧‧‧CO ₂ supply source

11, 12, 13, 14, 21, 22, 23, 24, 31, 32‧‧‧ connectors

50‧‧‧Control unit

94‧‧‧ pipeline

100‧‧‧Air conditioning system (heat exchange system)

150‧‧‧Sink

V1, V2‧‧‧ opening and closing valve

V3‧‧‧ Pressure reducing valve

V4‧‧‧ four-way valve

La‧‧‧Pipe Department

Lb‧‧‧1st heat medium pipeline

Lc‧‧‧2nd heat medium pipeline

La1~La5, Lb1~Lb5, Lc1, Lc2‧‧‧ pipeline

Vp1, Vp2, Vp3, Vp4‧‧‧ mouth

So‧‧‧ control signal line

TW1‧‧‧Temperature Sensor (Water Temperature Sensor)

B1, B2‧‧ bis points

Fig. 1 is a block diagram showing an outline of a first embodiment of the present invention.

Fig. 2 is a flow chart showing the control of switching the cold room/warm room in the first embodiment.

Fig. 3 is a view showing the flow of the heat medium in the case where the greenhouse operation is performed in Fig. 1;

Fig. 4 is a view showing the flow of the heat medium in the case where the cold room operation is performed in Fig. 1;

Fig. 5 is a partial cross-sectional view showing the flow of the heat medium during the operation of the greenhouse in the case where the pipe is formed into a double pipe.

Fig. 6 is a partial cross-sectional view showing the flow of the heat medium during the operation of the cold room in the case where the pipe is formed as a double pipe.

Fig. 7 is a block diagram showing the configuration of the lower end portion of the double tube.

Fig. 8 is a view showing a state in which the greenhouse operation is performed in Fig. 7.

Fig. 9 is a view showing a state in which the operation of the cold room is performed in Fig. 7.

Fig. 10 is a block diagram showing the upper end portion of the double tube.

Fig. 11 is a block diagram showing a modification of the upper end portion of the double tube.

Fig. 12 is a cross-sectional view showing a first modification of the double tube.

Fig. 13 is a longitudinal sectional view showing a second modification of the double tube.

Fig. 14 is a block diagram showing the control in the first embodiment.

Fig. 15 is a flowchart showing the control in Fig. 14.

Fig. 16 is a view showing a modification of the first embodiment.

Fig. 17 is a block diagram showing essential parts of a second embodiment of the present invention.

Fig. 18 is a block diagram showing essential parts of a third embodiment of the present invention.

Fig. 19 is a block diagram showing the construction procedure in the third embodiment.

Figure 20 is a block diagram showing the construction sequence following Figure 19.

Figure 21 is a block diagram showing the construction sequence following Figure 20.

Fig. 22 is a block diagram showing essential parts of a fourth embodiment of the present invention.

Fig. 23 is a block diagram showing essential parts of a fifth embodiment of the present invention.

Fig. 24 is a block diagram showing essential parts of a sixth embodiment of the present invention.

Figure 25 is a block diagram showing the experimental apparatus used in the experimental example.

Fig. 26 is a characteristic diagram showing experimental results at the time of a cold room.

Fig. 27 is a characteristic diagram showing experimental results at the time of a greenhouse.

Fig. 28 is a characteristic diagram showing the experimental results at the time of the cold room in the case where the operating conditions in Fig. 26 are changed.

Fig. 29 is a block diagram showing the control in the first embodiment.

Fig. 30 is a flowchart showing the control in Fig. 29.

1. . . 1st heat exchanger / outdoor unit

1h, 2h. . . Heat exchange department

2. . . 2nd heat exchanger / indoor unit

3. . . air conditioner

4. . . Air compressor

4i, 5i. . . suction point

4o, 5o. . . Spit

5. . . Pump

6, 7. . . Temperature sensor

11, 12, 13, 14, 21, 22, 23, 24, 31, 32. . . Connector

50. . . control unit

100. . . Air conditioning system (heat exchange system)

150. . . sink

V1, V2. . . Open and close valve

V3. . . Pressure reducing valve

V4. . . Four-way valve

La. . . Piping system

Lb. . . First heat medium pipeline

Lc. . . Second heat medium pipeline

La1～La5, Lb1～Lb5, Lc1, Lc2. . . Pipeline

Vp1, Vp2, Vp3, Vp4. . . Port

So. . . Control signal line

TW1. . . Temperature sensor (water temperature sensor)

B1, B2. . . Point of divergence

Claims (4)

A heat exchange system characterized by comprising: a water storage device (150, GH); and a piping system (La), immersed in the water of the water storage device (150, GH) and having the water storage device (150, GH) The water in the water exchange function, and includes: a compression type air conditioner having an outdoor unit (1), an indoor unit (2), an air conditioning load (3), an air compressor (4), and a four-way valve (V4) The piping system (La) is connected to the outdoor unit (1), wherein the heat medium flowing inside the piping system (La) is carbon dioxide, and the heat storage or condensation heat of the carbon dioxide is used to form the water storage device (150). The water in the GH) exchanges heat with the water in the water storage device (150, GH) by the heat of vaporization or condensation heat of the carbon dioxide, and is exposed in the piping system (La). The temperature of the carbon dioxide flowing through the area of the water storage device (150, GH) is set to 5 ° C to 40 ° C, and the piping system (La) is composed of a double tube (9), and the inner tube (91) flows through the liquid phase. Carbon dioxide, the outer tube (92) is configured to flow carbon dioxide in the gas phase, and the inner tube (91) and the outer tube (92) are connected via a pump (5), and the pump (5) The first opening and closing valve (V1) is provided at the outlet (5o) side, the second opening and closing valve (V2) is provided on the suction port (5i) side of the pump (5), and the first and second opening and closing valves (V1, V2) are provided. A branch line (La5) is provided on the side of the outdoor unit (1). A heat exchange system, comprising: a water storage device (150, GH); and a piping system (La) immersed in the water of the water storage device (150, GH) and having the water storage device (150, The water in GH) performs the function of heat exchange, and has: an outdoor unit (1), an indoor unit (2), The air conditioner load (3), the air compressor (4), and the four-way valve (V4) compression type air conditioner, wherein the piping system (La) is connected to the outdoor unit (1), and the inside of the piping system (La) The heat medium to be circulated is carbon dioxide, and heat is exchanged with the water in the water storage device (150, GH) by the heat of vaporization or condensation of the carbon dioxide, in order to utilize the heat of vaporization or condensation heat of the carbon dioxide and the water storage device ( 150. The water in the GH) is heat-exchanged, and the temperature of the carbon dioxide flowing in the region of the piping system (La) exposed to the water storage device (150, GH) is set to 5 ° C to 40 ° C, and the piping system is (La) is composed of a double tube (9), the inner tube (91) is configured to flow carbon dioxide in the liquid phase, the outer tube (92) is configured to flow carbon dioxide in the gas phase, and the inner tube (91) and the outer tube (the inner tube (91) and the outer tube ( 92) The pump (5) is connected, and the discharge port (5o) side of the pump (5) is connected to the inner tube (91) via a line (93) through which the first opening and closing valve (Vb3) is placed, and the pump (5) The suction port (5i) side is connected to the outer tube (92) via a line (94) through which the second opening/closing valve (Vb1) is placed, and the lower end of the inner tube (91) passes through the third opening and closing valve (Vb2) and the aforementioned The tube (92) is connected, and A control unit (50) for switching between a cold room and a warm room is provided. The control unit is configured to close the first and second on-off valves (Vb3, Vb1) in the warm room, open the third on-off valve (Vb2), and open the first in the cold room. And the second on-off valve (Vb3, Vb1), the third on-off valve (Vb2) is closed, and the pump (5) is activated. The heat exchange system according to claim 1 or 2, wherein the piping system (La) is provided with a discharge valve (Va) and a carbon dioxide supply amount adjusting valve (Vc), and has a control unit (50A), the control Unit (50A) has: from the discharge valve (Va) and carbon dioxide supply adjustment The valve opening degree of the valve (Vc) is used to determine the function of the carbon dioxide circulation amount; the carbon dioxide circulation amount is compared with the predetermined amount to determine whether the function is appropriate; if the carbon dioxide circulation amount is appropriate, the discharge valve (Va) and the carbon dioxide are maintained. The valve opening degree of the supply amount adjusting valve (Vc) increases the valve opening degree of the bleed valve (Va) and/or reduces the valve opening degree of the carbon dioxide supply amount adjusting valve (Vc) when the amount of carbon dioxide circulating is excessive. When the amount of carbon dioxide circulating is too small, the valve opening degree of the bleed valve (Va) and/or the valve opening degree of the carbon dioxide supply amount adjusting valve (Vc) are reduced. A heat exchange system according to claim 1 or 2, wherein the aforementioned piping system (La) is divided in a plurality of systems.