JP7533888B2 - Heat exchange system for cultivation facilities - Google Patents

Description

The present invention relates to a device for cooling air inside a cultivation facility.

Conventionally, plant cultivation facilities have had the problem that, depending on the season, the air temperature inside the facility can exceed the temperature suitable for the growth of the plants being cultivated.

For example, in plant factories where crops such as lettuce and strawberries are grown, the temperature inside the factory often becomes too high because the crops are exposed to light for photosynthesis, and for this reason air conditioning equipment is widely used to cool the air inside the factory.

For example, Patent Document 1 discloses a system that includes a large fan installed on one wall of a plant factory, a large, breathable pad installed on the opposing wall, and a water fountain means for spraying mist onto the pad; by rotating the fan, wind is sent into the factory through the pad moistened from outside, and the heat of vaporization of the water is used to cool the air inside the factory.

Patent Publication 2001-215027

However, this type of air conditioning equipment consumes a lot of power, which means high running costs for cooling the air inside the cultivation facility.

Therefore, the present invention aims to provide a heat exchange system for a cultivation facility that can effectively cool the air inside the cultivation facility at low running costs.

The object of the present invention is to
A heat exchange system for a cultivation facility for cultivating crops, comprising:
An air extraction means for extracting air from within the cultivation facility to the outside of the facility;
a first pipe for transporting the air taken out by the air taking-out means;
A first cooling tank provided outside the cultivation facility and containing a refrigerant;
a discharge section that discharges the air that is taken out of the cultivation facility by the air taking-out means and transported through the first piping into the cultivation facility,
A heat exchange system for a cultivation facility, characterized in that a portion of the first piping is disposed within the refrigerant contained in the first cooling tank.

According to the present invention, the air present in the cultivation facility is taken out of the facility by the air extraction means, cooled in the refrigerant contained in the first cooling tank while being transported through the first piping, and then released into the cultivation facility at the release section, thereby cooling the air in the cultivation facility.

In addition, according to the present invention, the air taken out of the cultivation facility is cooled by passing it through the refrigerant in the first cooling tank, which is a simple configuration, making it possible to reduce running costs.

Furthermore, according to the present invention, even if a large amount of light is brought into the cultivation facility, the air in the cultivation facility can be cooled by a heat exchange system to prevent the temperature inside the cultivation facility from rising, so that even crops with high light saturation points or light compensation points can be cultivated in the cultivation facility, making it possible to cultivate a wide variety of crops.

In a preferred embodiment of the present invention,
The air extraction means comprises a first perforated pipe, at least a portion of which is disposed within the cultivation facility, for extracting air within the cultivation facility;
The discharge section includes a second perforated pipe disposed within the cultivation facility, the second perforated pipe discharging the air transported by the first piping into the cultivation facility.

According to this preferred embodiment of the present invention, the heat exchange system for the cultivation facility includes a first perforated pipe that extracts air from within the cultivation facility and a second perforated pipe that releases air into the cultivation facility, so that air is uniformly extracted from within the cultivation facility through the multiple holes in the perforated pipe and uniformly supplied to the cultivation facility, effectively preventing wind from being generated within the cultivation facility.

In a further preferred embodiment of the present invention,
The portion of the first pipe disposed in the refrigerant in the first cooling tank is made of metal.

In this preferred embodiment of the present invention, the portion of the first pipe that transports air that is placed in the refrigerant is made of a metal with high thermal conductivity, so the air transported through the first pipe can be efficiently cooled.

In a further preferred embodiment of the present invention,
Furthermore, a pump that takes out the hydroponic solution from the cultivation tank provided in the cultivation facility to the outside of the cultivation facility;
a second pipe for transporting the hydroponic solution taken out by the pump;
a portion of the second pipe is disposed in the refrigerant contained in the first cooling tank or in the refrigerant contained in the second cooling tank;
The second pipe opens into the cultivation tank of the cultivation facility at its downstream end.

According to this preferred embodiment of the present invention, the hydroponic solution contained in the cultivation tank is removed to the outside of the cultivation facility by a pump, cooled in the refrigerant contained in the first cooling tank or the second cooling tank while being transported through the second piping, and then returned to the cultivation tank, so that the hydroponic solution contained in the cultivation tank can be effectively cooled.

In addition, according to this preferred embodiment of the present invention, the hydroponic liquid removed from the cultivation facility by the pump is cooled by passing it through the refrigerant contained in the first cooling tank or the second cooling tank while being transported through the second piping. This prevents changes in the components, pH, electrical conductivity, etc. of the hydroponic liquid, as occurs when cold water is added to the hydroponic liquid 57 for cooling.

In a further preferred embodiment of the present invention,
The portion of the second pipe disposed in the coolant in the first cooling tank or the second cooling tank is made of metal.

In this preferred embodiment of the present invention, the portion of the second pipe that transports the hydroponic liquid that is placed in the refrigerant is made of a metal with high thermal conductivity, so the hydroponic liquid transported through the second pipe can be efficiently cooled.

In a further preferred embodiment of the present invention, the refrigerant is water.

In a further preferred embodiment of the present invention,
Further, a temperature sensor provided in the cultivation facility;
a first flow passage opening/closing means for opening and closing a flow passage of air transported through the first piping;
A supply source of carbon dioxide gas to be released into the cultivation facility by the release unit;
a carbon dioxide gas supply pipe for transporting the carbon dioxide gas supplied from the supply source;
A carbon dioxide concentration sensor that measures a carbon dioxide concentration in the cultivation facility;
A second flow passage opening and closing means is provided for opening and closing the flow passage of carbon dioxide gas transported through the carbon dioxide gas supply pipe.

According to this preferred embodiment of the present invention, when the temperature inside the cultivation facility detected by the temperature sensor is high, the air extraction means is driven to start extracting air from the cultivation facility, and at the same time, the first flow path opening/closing means is controlled to open the air flow path, thereby making it possible to supply cooled air from the discharge section into the cultivation facility, thereby cooling the air inside the cultivation facility.

Furthermore, according to this preferred embodiment of the present invention, when the carbon dioxide concentration in the cultivation facility detected by the carbon dioxide concentration sensor is low, the second flow path opening/closing means is controlled to open the carbon dioxide flow path and supply carbon dioxide into the cultivation facility, thereby promoting photosynthesis of crops cultivated in the cultivation facility.

Furthermore, according to this preferred embodiment of the present invention, the air can be cooled by passing it through the first cooling tank, and at the same time, carbon dioxide gas can be supplied into the cultivation facility. This means that, unlike the case of cooling the air in the cultivation facility 2 by taking in outside air into the cultivation facility 2 using the system described in Patent Document 1, the carbon dioxide gas concentration in the cultivation facility, which has been increased by the supply of carbon dioxide gas from the carbon dioxide gas supply source, does not decrease as the air is cooled. This makes it possible to efficiently supply carbon dioxide gas to the crops in the cultivation facility, while preventing the waste of carbon dioxide gas and reducing running costs.

According to the present invention, the air in the cultivation facility is taken out from the air extraction means, cooled while passing through piping placed in the refrigerant contained in the first cooling tank, and then returned to the cultivation facility, so that the air in the cultivation facility can be effectively cooled, and at the same time, the air is cooled by a simple configuration in which the air taken out from the cultivation facility is passed through piping placed in the refrigerant, so that it is possible to provide a heat exchange system that can reduce running costs.

FIG. 1 is a schematic diagram showing the overall configuration of a heat exchange system according to a preferred embodiment of the present invention and a cultivation facility 2 to which the heat exchange system is applied. FIG. 2 is a partial cross-sectional schematic view of the vicinity of the air outlet means of the heat exchange system as viewed from the direction of the arrow α shown in FIG. FIG. 3 is a partial cross-sectional schematic view of the vicinity of a metal tube disposed in a first cooling tank of the heat exchange system shown in FIG. FIG. 4 is a partial cross-sectional view of the vicinity of the cultivation tank taken along line XX in FIG. 1, seen from the front side. FIG. 5 is a block diagram of a control system, a detection system, and a drive system of the heat exchange system shown in FIG. FIG. 6 is a flowchart showing the control procedure of the first cooling unit by the control unit for cooling the air inside the cultivation facility. FIG. 7 is a flowchart showing the procedure for controlling the supply of carbon dioxide gas into the cultivation facility by the control unit. FIG. 8 is a flowchart showing a control procedure of the second cooling unit by the control unit for cooling the hydroponic solution contained in the cultivation tank. FIG. 9 is a partial cross-sectional view of the vicinity of a cultivation tank in a cultivation facility to which a heat exchange system according to another preferred embodiment of the present invention is applied.

The following provides a detailed explanation of a preferred embodiment of the present invention with reference to the accompanying drawings.

Figure 1 is a schematic diagram showing the overall configuration of a heat exchange system 1 according to a preferred embodiment of the present invention and a cultivation facility 2 to which the heat exchange system 1 is applied.

The cultivation facility 2 in this embodiment is for cultivating leaf lettuce, and as shown in FIG. 1, the cultivation facility 2 is a highly airtight, roughly rectangular building, and includes a top surface 53, a wall 29 located on the left side and near side of the drawing, a wall 44 located on the right side and near side of the drawing, and a wall 66 located on the left side and far side of the drawing, and the top surface 53 is configured to allow sunlight to enter. In the following description, the wall 29 side of the cultivation facility 2 is referred to as the "front", and the opposite side is referred to as the "rear". Additionally, the side of wall 44 opposite wall 66 is referred to as the "front", and the opposite side is referred to as the "rear".

In addition, in FIG. 1, the lines representing the boundaries between the top surface 53, the walls 29, and the walls 44 are shown with dashed lines, and FIG. 1 shows a state in which not only the vicinity of the cultivation facility 2 but also the inside of the cultivation facility 2 can be seen through the top surface 53, the walls 29, and the walls 44.

As shown in FIG. 1, a cultivation tank 17 for hydroponic cultivation of leaf lettuce 34 is provided at the bottom of the cultivation facility 2.

As shown in FIG. 1, the heat exchange system 1 according to a preferred embodiment of the present invention includes a first cooling section 21 for cooling the air in the cultivation facility 2, a second cooling section 22 for cooling the hydroponic solution contained in the cultivation tank 17 provided at the lower end of the cultivation facility 2, and a control section 9 for controlling the operation of the entire heat exchange system 1.

As shown in FIG. 1, the first cooling section 21 includes an air extraction means 3 for extracting air from within the cultivation facility 2 to the outside of the cultivation facility 2, a first pipe 4 for transporting the air extracted by the air extraction means 3, a first cooling tank 5 for storing cold water, a carbon dioxide gas cylinder 20 for storing carbon dioxide gas to be supplied to the cultivation facility 2, a gas valve unit 19 provided on the first pipe 4 and configured to open and close the cooled air flow path and the carbon dioxide gas flow path, a release section 6 for releasing the cooled air or carbon dioxide gas transported by the first pipe 4 into the cultivation facility 2, and a sensor means 11 capable of measuring the temperature and carbon dioxide gas concentration in the vicinity of the leaf lettuce 34 in the cultivation facility 2.

The first pipe 4 extends through the cold water contained in the first cooling tank 5 and is configured to be able to cool the air extracted from the cultivation facility 2 by the air extraction means 3.

In other words, in the first cooling section 21, the air taken out from the cultivation facility 2 by the air taking-out means 3 flows through the first pipe 4, a part of which is placed in the cold water contained in the first cooling tank 5, where it is cooled, and is then released to the lower part of the cultivation facility 2 in the release section 6.

As shown in FIG. 1, the first piping 4 includes a first upstream pipe 41 connected to the air extraction means 3, a metal pipe 10 located in the first cooling tank 5 and connected to the lower end of the first upstream pipe 41, a downstream pipe 42 connected to the metal pipe 10 and the gas valve unit 19, and a first supply pipe 37 connected to the downstream side of the gas valve unit 19.

As shown in FIG. 1, in this embodiment, the discharge section 6 is provided with a second porous pipe 8 that is made of a pipe with multiple holes formed therein.

On the other hand, as shown in FIG. 1, the second cooling section 22 (on the right side of the drawing) includes a pump 14 that sends the hydroponic solution contained in the cultivation tank 17 out of the cultivation facility 2, a second pipe 15 that transports the hydroponic solution, a second cooling tank 16, and a second temperature sensor 30 that measures the temperature of the hydroponic solution in the cultivation tank 17.

As shown in FIG. 1, the second piping 15 includes a second upstream pipe 43, one end of which is connected to the pump 14, a metal pipe 31 located in the second cooling tank 16 and one end of which is connected to the other end of the second upstream pipe 43, and a second supply pipe 39, one end of which is connected to the other end of the metal pipe 31 and the other end of which is led into the cultivation tank 17 provided in the cultivation facility 2.

Therefore, in the second cooling section 22, the hydroponic solution extracted by the pump 14 from the cultivation tank 17 provided in the cultivation facility 2 is guided via the second upstream pipe 43 to the metal pipe 31 extending through the cold water contained in the second cooling tank 16, where it is cooled, and then recycled (circulated) to the cultivation tank 17 via the second supply pipe 39.

Figure 2 is a schematic partial cross-sectional view of the heat exchange system 1 near the air extraction means 3 as viewed from the direction of the arrow α shown in Figure 1, with the air flow indicated by dashed lines with arrows.

As shown in Figures 1 and 2, the air extraction means 3 includes an air compressor 25 provided outside the cultivation facility 2, a pipe 64 attached to the air compressor 25 and passing through a through hole 32 formed in the wall 29, and a first perforated pipe 7 connected to the rear of the pipe 64. The connection between the pipe 64 and the first perforated pipe 7 is preferably configured inside the cultivation facility 2 or inside the through hole 32, rather than outside the cultivation facility 2, in order to prevent a situation in which the carbon dioxide concentration decreases due to cooling.

The air pump 25 includes a motor (not shown in Figs. 1 and 2) that rotates the blades provided inside, an air inlet 54 (see Fig. 2) at the rear, and an air outlet 65 at the lower end. The piping 64 is connected to the air pump 25 with its front end surrounding the inlet 54. The motor of the air pump 25 is configured to be controllable by the control unit 9 shown in Fig. 1. The air pump 25 may be a blower, a propeller fan, a compressor, or the like. In this embodiment, the air pump 25 is fixed to a pillar 67 provided outside the cultivation facility 2.

In this embodiment, the first perforated pipe 7 is made of a pipe with many holes on its outer surface, and the first perforated pipe 7 extends in the front-to-rear direction.

As shown in FIG. 2, an annular cover 55 having a hole 56 connected to the through hole 32 is fixed around the through hole 32 formed in the wall 29, and the piping 64 extends through the hole 56 to the outside of the cultivation facility 2.

When the motor of the air compressor 25 is driven, the warm air present in the upper part of the cultivation facility 2 is taken into the interior through the numerous holes on the outer surface of the first porous pipe 7 and the opening at the rear of the first porous pipe 7 in FIG. 2, and then sucked into the interior through the suction port 54 of the air compressor 25 installed outside the cultivation facility 2 via the piping 64.

Here, if the air present in the cultivation facility 2 is extracted directly from the rear end of the piping 64 attached to the air compressor 25 without using the first perforated pipe 7, there is a risk that wind will be generated within the cultivation facility 2.

In contrast, in this embodiment, air from within the cultivation facility 2 is drawn into the first perforated pipe 7 not only through the rear end of the first perforated pipe 7, but also through numerous holes formed in the wall of the first perforated pipe 7, preventing wind from being generated within the cultivation facility 2.

When the motor of the air compressor 25 is driven, the air sucked into the suction port 54 is transported downward through the first upstream pipe 41 of the first piping 4 attached to the blow-out port 65.

Figure 3 is a schematic partial cross-sectional view of the vicinity of the metal tube 10 disposed in the first cooling tank 5 of the heat exchange system 1 shown in Figure 1.

In this embodiment, the first pipe 4 is arranged to penetrate from the upper end of the first cooling tank 5 into its interior, and at the penetration 5a to the first cooling tank 5, the lower end of the first upstream pipe 41 of the first pipe 4 is connected to the upper end of the upstream side of the metal pipe 10 arranged in the first cooling tank 5.

As shown in FIG. 3, the metal tube 10 is configured to extend in a spiral shape from the upper end of the first cooling tank 5 toward the lower end inside the first cooling tank 5. By arranging the metal tube 10 in a spiral shape in this manner, the area of contact between the metal tube 10 of the first piping 4 and the cold water is increased, and the air transported inside the first piping 4 is cooled more quickly.

In addition, in this embodiment, the portion of the first piping 4 located in the first cooling tank 5, i.e., the metal tube 10, is made of a metal with a higher thermal conductivity than other materials, which promotes heat exchange between the cold water contained in the first cooling tank 5 and the air in the metal tube 10 immersed in the cold water, thereby effectively cooling the air transported through the metal tube 10.

As shown in FIG. 2, the metal pipe 10 of the first piping 4 extends upward downstream of the spirally formed portion and is connected to one end of the downstream pipe 42 at the penetration 5b (see FIGS. 1 and 3) to the upper end of the first cooling tank, and the other end of the downstream pipe 42 is connected to the gas valve unit 19 as shown in FIG. 1.

On the other hand, a carbon dioxide gas supply pipe 35 extending from a carbon dioxide gas cylinder 20 is connected to the gas valve unit 19, and the gas valve unit 19 is configured to be able to open and close the flow path of the cooled air supplied through the first pipe 4 and the flow path of the carbon dioxide gas supplied from the carbon dioxide gas cylinder 20 based on an output signal from the control unit 9.

When the carbon dioxide gas flow path is opened, carbon dioxide gas is supplied to the first supply pipe 37 connected to the gas valve unit 19, and when the cooled air flow path is opened, cooled air is supplied to the first supply pipe 37.

In addition, in this embodiment, the gas valve unit 19 is provided with a check valve (not shown) to prevent the carbon dioxide gas supplied from the carbon dioxide gas cylinder 20 from flowing into the downstream pipe 42, and to prevent the cooled air supplied from the downstream pipe 42 from flowing into the carbon dioxide gas supply pipe 35.

A through hole (not shown) is formed in the lower part of the wall 29 on the front side of the cultivation facility 2, and as shown in FIG. 1, an annular cover 38 is provided around the through hole on the outer surface of the wall 29. The first supply pipe 37 is connected to the front end of the second perforated pipe 8 arranged in the cultivation facility immediately after it extends rearward from the through hole formed in the wall 29, i.e., at the front end within the cultivation facility 2.

If air or carbon dioxide gas is supplied directly into the cultivation facility 2 from the first supply pipe 37, there is a risk that wind will be generated inside the cultivation facility 2.

In contrast, in this embodiment, air or carbon dioxide gas is supplied from the first supply pipe 37 into the second perforated pipe 8, and then uniformly supplied into the cultivation facility 2 through the numerous holes formed in the wall of the second perforated pipe 8, thereby preventing wind from being generated within the cultivation facility 2.

Figure 4 is a partial cross-sectional view of the vicinity of the cultivation tank 17 along line X-X in Figure 1, viewed from the front side.

As shown in Figures 1 and 4, in the cultivation tank 17, a polystyrene foam plate 18 is provided above the water surface 58 of the hydroponic liquid 57, and the stems of the leaf lettuce 34 pass vertically through through holes 40 formed in the polystyrene foam plate 18.

As shown in Figures 1 and 4, the second perforated pipe 8 is positioned adjacent to the leaf lettuce 34 on the polystyrene foam plate 18 provided in the cultivation tank 17, and in this embodiment, the terminal opening is configured to be located within the cultivation tank 17.

Therefore, when the air cooled in the first cooling tank 5 is supplied to the second perforated pipe 8 via the gas valve unit 19 and the first supply pipe 37, the cooled air is released from the numerous holes formed in the wall of the second perforated pipe 8 and the terminal opening of the second perforated pipe 8, and as a result, the air in the cultivation facility 2 is cooled.

On the other hand, when carbon dioxide gas from the carbon dioxide gas cylinder 20 is supplied to the second perforated pipe 8 via the gas valve unit 19 and the first supply pipe 37, carbon dioxide gas is released near the leaf lettuce 34 from the numerous holes formed in the wall of the second perforated pipe 8 and the terminal opening of the second perforated pipe 8, promoting photosynthesis of the leaf lettuce 34.

As shown in Figures 1 and 4, a pump 14 is provided in the cultivation tank 17, and the second upstream pipe 43 of the second piping 15 is connected to the pump 14.

In this embodiment, the pump 14 is controlled by the control unit 9 and is used to transport the hydroponic solution 57 contained in the cultivation tank 17 to the outside of the cultivation facility 2 through the second upstream pipe 43.

The second piping 15 extends from inside the cultivation facility 2 to outside the cultivation facility 2, extends from the penetration 16a to the upper end of the second cooling tank 16 into the inside of the second cooling tank 16, and extends downward in a spiral shape inside the second cooling tank 16. The second upstream pipe 43 of the second piping 15 is connected to the metal pipe 31 inside the penetration 16a, that is, the second piping 15 is formed by the metal pipe 31 inside the second cooling tank 16. In this way, inside the second cooling tank 16, the second piping 15 is formed in a spiral shape by the metal pipe 31 with high thermal conductivity, so that the area in contact with the cold water contained in the second cooling tank 16 is increased, and the hydroponic liquid 57 transported inside the second piping 15 can be effectively cooled.

As shown in FIG. 1, the metal pipe 31 of the second piping 15 extends upward downstream of the spirally formed portion and is connected to the upstream end of the second supply pipe 39 located outside the second cooling tank 16 within the penetration portion 16b to the upper end of the second cooling tank 16. In this embodiment, the height of the second cooling tank 16 is configured to be lower than the height of the first cooling tank 5. By configuring it in this way, the hydroponic liquid 57 can pass through the downstream portion (the portion extending upward) of the metal pipe 31 without using power by utilizing the potential energy generated when the hydroponic liquid 57 descends through the portion of the second upstream pipe 43 located outside the cultivation facility 2 and the spirally formed portion of the metal pipe 31.

A through hole (not shown) is formed in the lower part of the wall 44 facing the second cooling tank 16 of the cultivation facility 2, and an annular cover 45 is provided around the through hole on the outer surface of the wall 44. The second supply pipe 39 extends into the cultivation facility 2 through the through hole formed in the wall 44 (see FIG. 1).

The downstream end of the second supply pipe 39 guided into the cultivation facility 2 is placed in the hydroponic liquid 57 of the cultivation tank 17 as shown in FIG. 4, and the hydroponic liquid 57 supplied from the metal pipe 31 in the second cooling tank 16 through the second supply pipe 39 into the cultivation tank 17 is sucked up from the cultivation tank 17 by the pump 14 and supplied to the second cooling tank 16 (see FIG. 1) by the second piping 15, where it is cooled. In this way, the cooled hydroponic liquid 57 can be returned to the cultivation tank 17 by the second supply pipe 39.

In this embodiment, the metal pipe 31 and the second supply pipe 39 of the second piping 15 are positioned so that the downstream portion is located lower than the upstream portion or at the same height as the upstream portion, so that the hydroponic solution 57 raised by the pump 14 to the upper end of the second cooling tank 16 can be smoothly circulated.

The downstream end of the second supply pipe 39 is located in front of the cross section taken along line X-X in FIG. 1, but is shown in FIG. 4 for convenience.

Figure 5 is a block diagram of the control system, detection system, and drive system of the heat exchange system 1 shown in Figure 1.

As shown in FIG. 5, the control system of the heat exchange system 1 includes a control unit 9 that controls the operation of the entire heat exchange system 1, a ROM 46 that stores control programs and the like, and a RAM 47 that stores various data.

As shown in FIG. 5, the detection system of the heat exchange system 1 includes a sensor means 11 (see FIG. 1) provided near the leaf lettuce 34 in the cultivation tank 17 and a second temperature sensor 30 (see FIG. 1) that detects the temperature of the hydroponic solution 57 contained in the cultivation tank 17, and the sensor means 11 includes a first temperature sensor 12 that detects the temperature of the air in the cultivation facility 2 and a carbon dioxide concentration sensor 13 that detects the concentration of carbon dioxide in the cultivation facility 2.

As shown in FIG. 5, the drive system of the heat exchange system 1 includes a motor 24 that rotates the blades of the air compressor 25, a solenoid valve 48 (first flow path opening and closing means) in the gas valve unit 19 (see FIG. 1) that opens and closes the downstream pipe 42 to which air cooled in the first cooling tank 5 is supplied, a solenoid valve 49 (second flow path opening and closing means) in the gas valve unit 19 that opens and closes the carbon dioxide supply pipe extending from the carbon dioxide cylinder 20 (see FIG. 1), and a pump 14 that extracts the hydroponic solution 57 contained in the cultivation tank 17 to the outside of the cultivation facility 2.

As shown in FIG. 5, the input system of the heat exchange system 1 includes a temperature setting switch 50 for setting the air temperature in the cultivation facility 2 and a display 51 for displaying the set temperature, and the temperature setting switch 50 and the display 51 are each attached to the outer surface of the control unit 9 shown in FIG. 1.

In the heat exchange system 1 according to a preferred embodiment of the present invention configured as described above, the air in the cultivation facility 2 is cooled by the control unit 9 as follows.

Figure 6 is a flowchart showing the control procedure of the first cooling unit 21 by the control unit 9 for cooling the air inside the cultivation facility 2.

As shown in FIG. 6, the control unit 9 first obtains a detection value of the air temperature inside the cultivation facility 2 from the first temperature sensor 12 of the sensor means 11 (see FIG. 1) (step S1).

Next, the control unit 9 determines whether the air temperature inside the cultivation facility 2 detected by the first temperature sensor 12 exceeds the temperature set by operating the temperature setting switch 50 (step S2).

If the result of the determination is that the air temperature inside the cultivation facility 2 exceeds the set temperature, the control unit 9 drives the motor 24 of the air compressor 25, and by rotating the blades, extracts the air inside the cultivation facility 2 into the first piping 4, and at the same time opens the solenoid valve 48 of the gas valve unit 19, and starts cooling the air inside the cultivation facility 2 by returning the air cooled in the first cooling tank 5 back into the cultivation facility 2 (step S3).

In contrast, if the result of the determination is that the air temperature inside the cultivation facility 2 is below the set temperature, the control unit 9 repeats obtaining the detection value from the first temperature sensor 12 and making a determination until the air temperature inside the cultivation facility 2 exceeds the set temperature.

After the first cooling section 21 starts cooling the air in the cultivation facility 2, the control section 9 acquires a detection value for the air temperature in the cultivation facility 2 from the first temperature sensor 12 (step S4).

After acquiring the detection value, the control unit 9 determines whether the air temperature inside the cultivation facility 2 is below the set temperature (step S5).

If the result of the determination is that the air temperature inside the cultivation facility 2 is equal to or lower than the set temperature, the control unit 9 stops driving the motor 24 of the air compressor 25 and closes the solenoid valve 48 of the gas valve unit 19 to stop cooling the air inside the cultivation facility 2 by the first cooling unit 21 (step S6).

After stopping the cooling of the air, the control unit 9 returns to step S1 and starts acquiring the detection value from the first temperature sensor 12.

On the other hand, if the result of the determination is that the air temperature inside the cultivation facility 2 is still above the set temperature, the motor 24 is driven and the solenoid valve 48 continues to be open, while the control unit 9 repeatedly obtains and determines the detection value from the first temperature sensor 12 until the air temperature inside the cultivation facility 2 falls below the set temperature.

Meanwhile, in this embodiment, the solenoid valve 49 is opened and closed by the control unit 9 to control the carbon dioxide concentration near the leaf lettuce 34 in the cultivation facility 2 as follows.

Figure 7 is a flowchart showing the procedure for controlling the supply of carbon dioxide gas into the cultivation facility 2 by the control unit 9.

As shown in FIG. 7, the control unit 9 first obtains the detected value of the carbon dioxide concentration in the cultivation facility 2 from the carbon dioxide concentration sensor 13 of the sensor means 11 (see FIG. 1) (step SS1).

Next, the control unit 9 determines whether the carbon dioxide concentration in the cultivation facility 2 detected by the carbon dioxide concentration sensor 13 is less than a predetermined value (step SS2).

If the result of the determination is that the carbon dioxide concentration in the cultivation facility 2 is below the predetermined value, the control unit 9 opens the solenoid valve 49 in the gas valve unit 19 (see Figure 1) to supply the carbon dioxide stored in the carbon dioxide cylinder 20 near the leaf lettuce 34 in the cultivation facility 2 (step SS3).

When the solenoid valve 49 that opens and closes the carbon dioxide gas supply pipe 35 is opened, the motor 24 is driven and the solenoid valve 48 is opened at the same time to cool the air in the cultivation facility 2 (see step S3 in FIG. 6), the cooled air supplied by the downstream pipe 42 shown in FIG. 1 and the carbon dioxide gas supplied from the carbon dioxide gas cylinder 20 through the carbon dioxide gas supply pipe 35 are mixed and supplied into the cultivation facility 2 through the first supply pipe 37 and the second perforated pipe 8. In this case, it is possible to simultaneously cool the air in the cultivation facility 2 and increase the carbon dioxide gas concentration in the vicinity of the leaf lettuce 34.

In contrast, if the result of the determination is that the carbon dioxide concentration is equal to or greater than the predetermined value, the control unit 9 repeats obtaining the detection value from the carbon dioxide concentration sensor 13 and making a determination until the carbon dioxide concentration in the cultivation facility 2 falls below the predetermined value.

Meanwhile, after starting the supply of carbon dioxide gas into the cultivation facility 2 in step SS3, the control unit 9 acquires a detection value from the carbon dioxide gas concentration sensor 13 of the sensor means 11 (step SS4).

After thus obtaining the detected value of the carbon dioxide gas concentration within the cultivation facility 2, the control unit 9 determines whether the detected carbon dioxide gas concentration is equal to or greater than a predetermined value (step SS5).

If the carbon dioxide concentration in the cultivation facility 2 is equal to or greater than the predetermined value, the control unit 9 closes the solenoid valve 49 to stop the supply of carbon dioxide to the cultivation facility 2 (step SS6). Next, the control unit 9 returns to step SS1 and starts acquiring the detection value from the carbon dioxide concentration sensor 13.

On the other hand, if the result of the judgment is that the carbon dioxide concentration in the cultivation facility 2 is still below the predetermined value, the supply of carbon dioxide to the cultivation facility 2, i.e., the solenoid valve 49 continues to be open, and at the same time, the control unit 9 repeatedly obtains and judges the detection value from the carbon dioxide concentration sensor 13 until the carbon dioxide concentration in the cultivation facility 2 becomes equal to or greater than the predetermined value.

Meanwhile, in this embodiment, the pump 14 is driven by the control unit 9 to cool the hydroponic solution 57 contained in the cultivation tank 17 as follows.

Figure 8 is a flowchart showing the control procedure of the second cooling unit 22 by the control unit 9 for cooling the hydroponic solution 57 contained in the cultivation tank 17.

As shown in FIG. 8, the control unit 9 first obtains the detected temperature value of the hydroponic solution 57 in the cultivation tank 17 from the second temperature sensor 30 shown in FIG. 1 (step SSS1).

Next, the control unit 9 determines whether the temperature of the hydroponic solution 57 detected by the second temperature sensor 30 exceeds the temperature set by operating the temperature setting switch 50 (step SSS2).

If the determination result indicates that the temperature of the hydroponic liquid 57 exceeds the set temperature, the control unit 9 drives the pump 14 to cool the hydroponic liquid 57 in the second cooling tank 16 via the second piping 15, and then returns the hydroponic liquid 57 to the cultivation tank 17, thereby starting cooling the hydroponic liquid 57 (step SSS3).

In contrast, if the determination result is that the temperature of the hydroponic liquid 57 contained in the cultivation tank 17 is below the set temperature, the control unit 9 repeats obtaining and determining the detection value from the second temperature sensor 30 until the temperature of the hydroponic liquid 57 exceeds the set temperature.

Thus, after starting to cool the hydroponic liquid 57, the control unit 9 acquires the detection value of the temperature of the hydroponic liquid 57 from the second temperature sensor 30 (step SSS4).

After acquiring the detection value, the control unit 9 determines whether the air temperature inside the cultivation facility 2 is below the set temperature (step SSS5).

As a result, if the temperature of the hydroponic liquid 57 is equal to or lower than the set temperature, the control unit 9 stops driving the pump 14 to stop cooling the hydroponic liquid 57 (step SSS6). Next, the control unit 9 returns to step SSS1 and starts acquiring the detection value from the second temperature sensor 30.

On the other hand, if the result of the determination is that the temperature of the hydroponic liquid 57 is still above the set temperature, cooling of the hydroponic liquid 57, i.e., operation of the pump 14, is continued, and at the same time, the control unit 9 repeatedly obtains and determines the detection value from the second temperature sensor 30 until the temperature of the hydroponic liquid 57 falls below the set temperature.

In this embodiment, the warm air present in the upper part of the cultivation facility 2 is taken out of the cultivation facility 2 by the air compressor 25 of the air extraction means 3, and while being transported through the metal tube 10 of the first piping 4 placed in the cold water contained in the first cooling tank 5, it is cooled by the cold water and recycled to the lower part of the cultivation facility 2, thereby cooling the air in the cultivation facility 2.

In addition, according to this embodiment, the air is cooled by a simple configuration in which the air taken out from the cultivation facility 2 by the air taking-out means 3 passes through a metal pipe 10 placed in cold water contained in the cooling tank 5, so it is possible to reduce the running costs for cooling the air. If rainwater or groundwater is used as the cold water, the running costs can be further reduced.

Furthermore, according to this embodiment, the heat exchange system 1 of the cultivation facility 2 is configured to extract the air within the cultivation facility 2 to the outside of the cultivation facility 2 through the first perforated pipe 7 of the air extraction means 3, and to take in the air outside the cultivation facility 2 into the cultivation facility 2 through the second perforated pipe 8 of the discharge section 6. Therefore, when air is extracted from the cultivation facility 2 and when it is returned to the cultivation facility 2, it is possible to effectively prevent wind from being generated within the cultivation facility 2 due to air movement, and it is possible to effectively prevent carbon dioxide gas supplied near the leaf lettuce 34 from being immediately diffused throughout the entire cultivation facility 2 due to the generation of wind.

In addition, according to this embodiment, the portions of the first pipe 4 shown in Figures 1 to 3 and the second pipe 15 shown in Figure 1 that are placed in the cold water contained in the first cooling tank 5 or the second cooling tank 16 are composed of metal pipes 10 or 31, respectively, so that the air and hydroponic solution 57 taken out of the cultivation facility 2 can be efficiently cooled, respectively.

Furthermore, according to this embodiment, as shown in FIG. 6, when the detected temperature inside the cultivation facility 2 output from the first temperature sensor 12 of the sensor means 11 (see FIG. 1) exceeds the temperature set by operating the temperature setting switch 50, the control unit 9 drives the motor 24 of the air compressor 25 and simultaneously opens the solenoid valve 48 of the gas valve unit 19 to start cooling the air. As a result, when the detected temperature inside the cultivation facility 2 falls below the set temperature, the control unit 9 stops driving the motor 24 and simultaneously closes the solenoid valve 48 to stop cooling the air, so that the temperature inside the cultivation facility 2 can be automatically adjusted.

In addition, according to this embodiment, the hydroponic solution 57 in the cultivation tank 17 is taken out of the cultivation facility 2 through the second piping 15 by the pump 14, cooled in the cold water contained in the second cooling tank 16, and then returned to the cultivation tank 17, so that the temperature of the hydroponic solution 57 contained in the cultivation tank 17 can be automatically controlled to a predetermined temperature.

Furthermore, according to this embodiment, the hydroponic liquid 57 taken out of the cultivation facility 2 by the pump 14 is cooled by passing it through the metal tube 31 of the second piping 15 placed in the cold water contained in the second cooling tank 16. Therefore, unlike the case where the hydroponic liquid 57 is cooled by adding cold water to the hydroponic liquid 57, the components, pH, electrical conductivity, etc. of the hydroponic liquid 57 do not change.

In addition, according to this embodiment, the control unit 9 is configured to open and close the solenoid valve 49 of the gas valve unit 19 based on the detection value of the carbon dioxide concentration sensor 13, as shown in FIG. 7. Therefore, when the carbon dioxide concentration in the cultivation facility is low, the solenoid valve 49 is opened to supply carbon dioxide into the cultivation facility 2 via the first supply pipe 37 (see FIG. 1) and the second perforated pipe 8 (see FIG. 1 and FIG. 4), thereby promoting photosynthesis of the leaf lettuce 34.

Furthermore, according to this embodiment, the air in the cultivation facility 2 is extracted by the air extraction means 3 and cooled by passing it through the metal tube 10 of the first cooling section 21. Therefore, unlike in the case where outside air is taken into the cultivation facility 2 to cool the air in the cultivation facility 2, the carbon dioxide concentration in the cultivation facility 2 does not decrease as the air is cooled. Therefore, carbon dioxide can be efficiently supplied to the leaf lettuce 34, while at the same time preventing the waste of carbon dioxide, and making it possible to reduce running costs.

Figure 9 is a partial cross-sectional view of the vicinity of the cultivation tanks 17a to 17c in a cultivation facility 2 to which a heat exchange system 1 according to another preferred embodiment of the present invention is applied.

As shown in FIG. 9, in this embodiment, a total of three cultivation tanks are arranged vertically in the cultivation facility 2: cultivation tank 17a located at the top, cultivation tank 17b located below it, and cultivation tank 17c located even lower. Cultivation tank 17a or 17b is located above cultivation tank 17b and 17c, and since the light taken into the cultivation facility 2 cannot be irradiated onto the leaf lettuce 34, lights 59 are provided above cultivation tanks 17b and 17c, respectively. Note that the first porous pipe 8 and various sensors are omitted in FIG. 9.

In this embodiment, the upper cultivation tank 17a is integrally formed with the pipe 60 so that the pipe 60 extends vertically through its bottom surface 61, and the middle cultivation tank 17b is integrally formed with the pipe 60 so that the pipe 62 extends vertically through its bottom surface 61. By configuring it in this way, it is possible to cool the hydroponic solution 57 in all of the cultivation tanks 17a to 17c with one motor 14.

Specifically, first, based on the output value from the second temperature sensor 30 (see FIG. 1) placed in the hydroponic liquid 57 in the lower cultivation tank 17c, the control unit 9 drives the motor 14 provided in the hydroponic liquid 57 contained in the lower cultivation tank 17c, and extracts the hydroponic liquid 57 to the outside of the cultivation facility 2 through the second upstream pipe 43 of the first piping 15.

In this way, the hydroponic solution 57 taken out of the lower cultivation tank 17c is cooled by gravity as it passes through the metal pipe 31 placed in the cold water contained in the second cooling tank 16 provided outside the cultivation facility 2 to the lower end, as in the embodiment shown in Figures 1 to 8, and then transferred into the cultivation facility 2 by the second supply pipe 39 arranged so that the downstream portion is at a lower position than or at the same position as the more upstream portion.

In this embodiment, the downstream end of the second supply pipe 39 is disposed in the upper cultivation tank 17a as shown in FIG. 9, and therefore the hydroponic solution 57 cooled in the second cooling tank 16 is supplied to the upper cultivation tank 17a.

Here, the upper end 60a of the pipe 60 of the upper cultivation tank 17a is configured to be located below the polystyrene foam plate 18 provided in the cultivation tank 17a. As a result, when the height position of the water surface 58 of the hydroponic liquid 57 in the upper cultivation tank 17a exceeds the upper end 60a of the pipe 60 due to the supply of the hydroponic liquid 57 from the second supply pipe 39, the hydroponic liquid 57 is supplied through the pipe 60 to the middle cultivation tank 17b.

Similarly, in the middle cultivation tank 17b, the upper end 62a of the pipe 62 penetrating the bottom surface 61 is configured to be located below the polystyrene foam plate 18 provided in the cultivation tank 17b. As a result, when the height position of the water surface 58 of the hydroponic liquid 57 in the intermediate cultivation tank 17b exceeds the upper end 62a of the pipe 62 as the hydroponic liquid 57 is supplied from above through the pipe 60, the hydroponic liquid 57 is supplied through the pipe 62 to the lower cultivation tank 17c.

The hydroponic solution 57 supplied to the lower cultivation tank 17c is cooled again in the second cooling tank 16 by the motor 14, and then recycled (circulated) back into the upper cultivation tank 17a through the second supply pipe 39.

According to this embodiment shown in FIG. 9, the hydroponic liquid 57 contained in the three vertically arranged cultivation tanks 17a to 17c can be cooled by driving a single motor 14 based on an output signal from the control unit 9. Therefore, compared to a case where a motor 14 is provided in each of the three cultivation tanks 17a to 17c and the hydroponic liquid 57 is removed outside the cultivation facility 2, the configuration of the second cooling unit 22 required for cooling the hydroponic liquid 57 can be simplified and the running costs for cooling can be effectively reduced.

The present invention is not limited to the above embodiments, and various modifications are possible within the scope of the invention described in the claims, and it goes without saying that these are also included within the scope of the present invention.

For example, in the embodiment shown in Figures 1 to 8, leaf lettuce is hydroponically grown in a cultivation tank 17 provided in the cultivation facility 2, but other crops such as lettuce, strawberries, and blueberries may also be grown.

In addition, in each embodiment shown in Figures 1 to 9, the heat exchange system 1 is applied to an airtight, roughly rectangular building as an example of a cultivation facility, but the cultivation facilities to which the heat exchange system 1 is applied are not limited to this, and in addition to general vinyl greenhouses, it can also be applied to special cultivation facilities such as rooms built underground for cultivating softened udo.In this case, the air in the room can be cooled by the heat exchange system 1 even in summer when the air temperature in the room becomes high, making it possible to cultivate softened udo regardless of the season.

Furthermore, in each embodiment shown in Figs. 1 to 9, a second porous pipe 8 is arranged near the leaf lettuce grown hydroponically in the cultivation tank 17, and the air in the cultivation facility 2 can be cooled, but the cultivation method is not limited to hydroponics. For example, when growing crops in a medium such as soil piled up at the bottom of a cultivation facility such as a vinyl greenhouse, a discharge section configured as a pipe can be arranged in the medium to cool the medium that has stored heat, particularly in the summer, and as a result, the temperature of the air in the cultivation facility can be lowered. In this case, the air compressed by the compressor may be cooled and then supplied to the medium.

In the embodiment shown in Figures 1 to 8, cold water is used as the refrigerant in the first cooling tank 5 and the second cooling tank 16, but a refrigerant other than water can also be used.

Furthermore, in the embodiment shown in Figures 1 to 8, the air in the cultivation facility 2 is taken out of the cultivation facility 2, cooled in the first cooling section 5, and then circulated back into the cultivation facility 2. However, the air taken out of the cultivation facility 2 may be discharged outside the facility without being circulated back into the facility 2, and the cooled carbon dioxide gas may be supplied near the leaf lettuce 34 in the cultivation facility 2, thereby simultaneously cooling the air in the cultivation facility 2 and promoting photosynthesis of the leaf lettuce 34.

In the embodiment shown in Figures 1 to 8, the second perforated pipe 8 is placed near the leaf lettuce 34 in the cultivation tank 17, but the location of the second perforated pipe 8 is not limited to this as long as it is within the cultivation facility 2.

In addition, in the embodiment shown in Figures 1 to 8, air is extracted from the cultivation facility 2 by only the air compressor 25 and returned to the cultivation facility 2. However, the rear end of the first supply pipe 37, the front end of which is connected to the gas valve unit 19, can be extended into the cultivation facility 2 and connected to the intake port of the compression means, so that the air cooled in the first cooling tank 5 is pulled into the cultivation facility 2, thereby further improving the air circulation. In this case, the generation of wind within the cultivation facility 2 can be prevented by attaching a perforated pipe to the outlet of the compression means.

Furthermore, in the embodiment shown in Figs. 1 to 8, the air in the cultivation facility 2 is cooled by passing it through the metal pipe 10 of the first pipe 4 placed in the cold water contained in the first cooling tank 5, and the hydroponic liquid 57 contained in the cultivation tank 17 is cooled by passing it through the metal pipe 31 of the second pipe 15 placed in the cold water contained in the second cooling tank 16. However, it is also possible to place the metal pipe 10 of the first pipe 4 and the metal pipe 31 of the second pipe 15 in cold water contained in the same (single) cooling tank, and to cool the air by passing it through the metal pipe 10 and cool the hydroponic liquid 57 by passing it through the metal pipe 31.

In the embodiment shown in Figures 1 to 8, the solenoid valves 48 and 49 of the gas valve unit 19 are opened to supply cooled air and carbon dioxide gas through the first supply pipe 37 and the second perforated pipe 8 into the cultivation facility 2. However, the solenoid valves 48 and 49 may each be configured as flow rate control valves, and the air cooled in the first cooling tank 5 may be mixed with carbon dioxide gas supplied from the carbon dioxide gas cylinder 20 in a desired ratio to supply cooled air with an increased carbon dioxide gas concentration into the cultivation facility 2.

In the embodiment shown in Figs. 1 to 8, the gas valve unit 19 is configured to be able to supply cooled air and carbon dioxide gas to the cultivation facility 2 by opening and closing the solenoid valves 48 and 49. In addition, an oxygen supply source such as an oxygen cylinder can be connected to the gas valve unit 19 to supply oxygen or cooled air with a high oxygen concentration to the cultivation facility 2. By configuring in this way, oxygen can be supplied to the leaf lettuce 34 when photosynthesis is not taking place, thereby promoting the respiration of the leaf lettuce 34. In this case, as in the case of supplying carbon dioxide gas, the oxygen concentration in the cultivation facility 2 does not decrease as the air cools, so the running costs for oxygen supply can be kept low.

In the embodiment shown in Figures 1 to 8, the first cooling tank 5 is configured to store cold water so that the air transported through the first pipe 4 can be cooled. However, during periods when the temperature inside the cultivation facility is low, the tank may be configured to store a heat medium such as warm air, and the air removed from the cultivation facility may be heated in the heat medium while being transported through the first pipe, and the air may be returned from the discharge section to the cultivation facility, thereby heating the air inside the cultivation facility.

In the embodiment shown in Figs. 1 to 8, the first supply pipe 37 shown in Fig. 1 is connected to the second perforated pipe 8 at the front end in the cultivation facility 2, but as long as the first supply pipe 37 and the second perforated pipe 8 are connected in the cultivation facility 2, it is not necessarily necessary to configure the connection point at the front end in the cultivation facility. For example, by configuring the first supply pipe 37 and the second perforated pipe 8 to be connected near the cultivation tank 17, it is possible to supply carbon dioxide gas intensively near the leaf lettuce 34, which can further promote the photosynthesis of the leaf lettuce 34 and at the same time, it is possible to suppress the waste of carbon dioxide gas. Similarly, the connection part between the piping 64 arranged at the top of the cultivation facility 2 and the first perforated pipe 7 may be arranged in the through hole 32 shown in Fig. 2 or in the cultivation facility 2.

Furthermore, in the embodiment shown in Figs. 1 to 8, as shown in Figs. 6 and 8, when cooling of the air or hydroponic liquid 57 is started and stopped, the control unit 9 controls the start and stop of cooling based on the temperature set by operating the temperature setting switch 50. However, the reference temperature when cooling of the air or hydroponic liquid 57 is started and the reference temperature when cooling is stopped may be configured to be different. In this case, it is possible to configure the cooling of the air by the first cooling unit 21 to start when the temperature of the air in the cultivation facility 2 rises and reaches, for example, 25°C, and to stop cooling the air when the temperature of the air in the cultivation facility 2 drops to, for example, 15°C.

In the embodiment shown in Figures 1 to 8, a metal pipe 10 is used for the portion of the first piping 4 shown in Figure 1 that is located in the first cooling tank 5, and a metal pipe 31 is used for the portion of the second piping 15 shown in Figure 1 that is located in the second cooling tank 16, but water hoses can be used instead of the metal pipes 10 and 31.

In addition, in the embodiment shown in Figures 1 to 8, the height of the second cooling tank 16 is made low (flat), so that the potential energy generated when the hydroponic liquid 57 flows through the portion of the second upstream pipe 43 located outside the cultivation facility 2 and the spirally formed portion of the metal pipe 31 can be utilized to transport the hydroponic liquid 57 downstream (upward extending portion) to the second supply pipe 39 located at the upper end of the second cooling tank 16. However, the height of the second cooling tank 16 may be made even lower to increase the speed at which the hydroponic liquid 57 flows downward, making it easier to transport the hydroponic liquid 57 from the metal pipe 31 to the second supply pipe 39.

Furthermore, in the embodiment shown in FIG. 9, the hydroponic liquid 57 taken out using a single motor 14 and cooled in the second cooling tank 16 is supplied to the upper cultivation tank 17a by gravity, as in the embodiment shown in FIGS. 1 to 8, and then can be supplied from the upper cultivation tank 17a to the middle cultivation tank 17b and from the middle cultivation tank 17b to the lower cultivation tank 17c using pipes 60 and 62. However, as long as the hydroponic liquid 57 cooled in the second cooling tank 16 can be taken out of the facility by a single motor and supplied to all cultivation tanks 17 without applying power, the configuration is not particularly limited.

1 Heat exchange system 2 Cultivation facility 3 Air extraction means 4 First piping 5 First cooling tank 5a Penetration portion 5b Penetration portion 6 Discharge portion 7 First perforated pipe 8 Second perforated pipe 9 Control unit 10 Metal pipe 11 Sensor means 12 First temperature sensor 13 Carbon dioxide concentration sensor 14 Pump 15 Second piping 16 Second cooling tank 16a Penetration portion 16b Penetration portion 17 Cultivation tank 17a Cultivation tank 17b Cultivation tank 17c Cultivation tank 18 Styrofoam plate 19 Gas valve unit 20 Carbon dioxide gas cylinder 21 First cooling portion 22 Second cooling portion 23 Blade 24 Motor 25 Air compressor 26 Rotating shaft 27 Different diameter socket 28 Opening 29 Wall 30 Second temperature sensor 31 Metal pipe 32 Through hole 33 Cold water 34 Leaf lettuce 35 Carbon dioxide gas supply pipe 36 Housing 37 First supply pipe 38 Cover 39 Second supply pipe 40 Through hole 41 First upstream pipe 42 Downstream pipe 43 Second upstream pipe 44 Wall 45 Cover 46 ROM
47 RAM
48 Solenoid valve 49 Solenoid valve 50 Temperature setting switch 51 Display 52 Opening 53 Top surface 54 Intake port 55 Cover 56 Hole 57 Hydroponic liquid 58 Water surface of hydroponic liquid 59 Light 60 Pipe 60a Upper end 61 Bottom surface 62 Pipe 62a Upper end 63 Cover 64 Pipe 65 Air outlet 66 Wall 67 Pillar

Claims (6)

A heat exchange system for a cultivation facility for cultivating crops, comprising:
An air extraction means for extracting air from within the cultivation facility to the outside of the facility;
a first pipe for transporting the air taken out by the air taking-out means;
A first cooling tank provided outside the cultivation facility and containing a refrigerant;
a discharge section that discharges the air that is taken out of the cultivation facility by the air taking-out means and transported through the first piping into the cultivation facility,
The first pipe is characterized in that a portion of the first pipe is disposed in the refrigerant contained in the first cooling tank , and further
A temperature sensor provided in the cultivation facility;
a first flow passage opening/closing means for opening and closing a flow passage of air transported through the first piping;
A supply source of carbon dioxide gas to be released into the cultivation facility by the release unit;
a carbon dioxide gas supply pipe for transporting the carbon dioxide gas supplied from the supply source;
A carbon dioxide concentration sensor that measures a carbon dioxide concentration in the cultivation facility;
a second flow passage opening/closing means for opening and closing a flow passage of the carbon dioxide gas transported through the carbon dioxide gas supply pipe;
The air extraction means is configured to suck air through a first perforated pipe arranged above a cultivation tank in which crops are grown and extending in a longitudinal direction of the cultivation tank,
A heat exchange system for a cultivation facility, characterized in that the release section is arranged near the top surface of the cultivation tank and is configured to supply air mixed with carbon dioxide gas through a second perforated pipe arranged to extend in the longitudinal direction of the cultivation tank. The air extraction means comprises a first perforated pipe, at least a portion of which is disposed within the cultivation facility, for extracting air within the cultivation facility;
The heat exchange system for a cultivation facility as described in claim 1, characterized in that the discharge section is a second perforated pipe arranged within the cultivation facility, and is provided with a second perforated pipe that discharges air transported by the first piping into the cultivation facility. The heat exchange system for a cultivation facility according to claim 1 or 2, characterized in that the portion of the first piping disposed in the refrigerant in the first cooling tank is made of metal. Furthermore, a pump that takes out the hydroponic solution from the cultivation tank provided in the cultivation facility to the outside of the cultivation facility;
a second pipe for transporting the hydroponic solution taken out by the pump;
a portion of the second pipe is disposed in the refrigerant contained in the first cooling tank or in the refrigerant contained in the second cooling tank;
A heat exchange system for a cultivation facility as described in any one of claims 1 to 3, characterized in that the second pipe opens at a downstream end into the cultivation tank of the cultivation facility. The heat exchange system of a cultivation facility as described in claim 4, characterized in that the portion of the second piping arranged in the refrigerant in the first cooling tank or the second cooling tank is made of metal and is formed in a spiral shape . The heat exchange system for a cultivation facility according to any one of claims 1 to 5, characterized in that the refrigerant is water.