JPH0548656U - Hydroponics device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a hydroponic culture device that can be sterilized by heating with a heat pump for small electric power and that can easily control heating and cooling of a fluid. A heating solution for heating and sterilizing the nutrient solution 12 and a cooling section 21 for cooling the nutrient solution are provided, and the heating and cooling are performed by a heat pump 40, which is a heat radiation section 41 of the heat pump 40. A warm water circulation passage 31 in which warm water circulates through the heating unit 20, and a warm water pump 3 which sends the warm water heated by the heat radiating unit 41 to the heating unit while circulating in the warm water circulation passage.
2, a cold water circulation path 44 in which cold water circulates between the heat absorbing section 47 and the cooling section 21 of the heat pump 40, and a cold water pump 45 that sends the cold water cooled by the heat absorbing section 47 to the cooling section while circulating the cold water in the cold water circulating path. And a heat exchanger that causes the nutrient solution before passing through the heating section to exchange heat with the nutrient solution that has passed through the heating section in a flow path between the heating section 20 and the cooling section 21 and then pass through the heating section 20. 22 and 22 are provided.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a nutrient solution cultivation device in which a nutrient solution is heat-sterilized and cooled, and then the nutrient solution is sent to a nutrient solution bed for cultivating plants, and the heating and cooling are performed by a heat pump.

[0002]

[Prior Art]

 Conventionally, as such a hydroponics device, one shown in FIG. 6 is known (see Japanese Patent Laid-Open No. 60-184331).

In FIG. 6, reference numeral 1 is a flow path provided with a pump P for feeding the nutrient solution 3 stored in a nutrient solution tank 2 to a nutrient solution cultivation bed 5 for cultivating a plant 4. A heating unit 6 and a cooling unit 7 are provided. The heating unit 6 heats and sterilizes the inflowing nutrient solution 3, and the cooling unit 7 cools the heated nutrient solution. Reference numeral 8 is a heat pump for heating the heating unit 6 and cooling the cooling unit 7, 8a is a condenser of the heat pump 8, and 8b is an evaporator of the heat pump 8. 8c is a compressor, and 8d is a pressure reducing valve.

[0004]

[Problems to be solved by the device]

 In such a hydroponics device, since the low temperature nutrient solution 3 is heated to a high temperature and sterilized only by the heat radiated by the heat pump 8, a heat pump for high power is required. Since the heat radiated by No. 8 is used only in the heating section, there were problems such as low effective use of heat.

Further, if the temperature of the nutrient solution 3 is low, the temperature may not rise to a temperature at which the fluid 5a can be sterilized in the heating section 1, and there is a problem that sterilization cannot be performed sufficiently. Further, if the temperature of the nutrient solution 3 is high, the temperature of the heated nutrient solution 3 becomes too high, and the cooling unit 7 cannot cool it to a predetermined temperature, which has a problem that it affects the growth of plants. .. To solve this problem, the heat pump 8 may be controlled. However, when the heat pump 8 is controlled to increase the heat radiation amount of the condenser 8a, the heat absorption amount of the evaporator 8b also increases, so that the nutrient solution 3a is heated while keeping the temperature of the cooled nutrient solution 3b constant. There is a problem that it is very difficult to control the temperature of the nutrient solution 3b because it is not possible to raise only the temperature of the nutrient solution or, conversely, it is not possible to lower the temperature of the nutrient solution 3b while keeping the temperature of the nutrient solution 3a constant. It was

The present invention has been made in view of the above problems, and an object thereof is to perform heat sterilization with a heat pump for small electric power and to easily control heating and cooling of a nutrient solution. The purpose of the present invention is to provide a hydroponic cultivation device that can effectively utilize heat.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention has a hydroponic bed for cultivating plants with a nutrient solution, a nutrient solution tank for storing the nutrient solution, and a nutrient solution in the nutrient solution for the nutrient solution cultivation bed. A heating section for heating and sterilizing the nutrient solution and a cooling section for cooling the heated nutrient solution, and a heating and cooling section of the heating section. Is a hydroponic cultivation apparatus that cools the heat pump with a heat pump, in which hot water circulates between the heat radiating portion and the heating portion of the heat pump, heats the hot water in the heat radiating portion, and flows into the heating portion with the hot water. A hot water circulation path for heating the nutrient solution; a hot water pump for sending the hot water heated by the heat dissipation section to the heating section while circulating the hot water in the hot water circulation path; and a cold water for the heat absorption section and the cooling section of the heat pump. It circulates, cools cold water in the endothermic part, and cools it with the cold water. A cold water circulation path for cooling the fluid in the cooling section, a cold water pump for sending the cold water cooled by the heat absorption section to the cooling section while circulating the cold water in the cold water circulation path, and a flow between the heating section and the cooling section. A feature is that the passage is provided with a heat exchanger that heat-exchanges the nutrient solution before passing through the heating section with the nutrient solution that has passed through the heating section and then passes through the heating section.

Further, a hydroponic bed for cultivating plants with a nutrient solution, a nutrient solution tank for storing the nutrient solution, and a circulation path for circulating the nutrient solution in the nutrient solution to the nutrient solution bed, A sub-circulation having a heating part for injecting and sterilizing by heating the nutrient solution in the nutrient solution tank and a cooling part for cooling the heated nutrient solution, and returning the nutrient solution passing through this cooling part to the nutrient solution tank. A hydroponic cultivation apparatus that includes a passage and performs heating of the heating unit and cooling of the cooling unit by a heat pump, in which hot water circulates between the heat radiating unit and the heating unit of the heat pump, and the hot water is heated by the heat radiating unit. A hot water circulation path for heating the nutrient solution flowing into the heating section with the hot water; and a hot water pump for sending the hot water heated by the heat radiation section to the heating section while circulating the hot water in the hot water circulation path. Cold water circulates through the heat absorbing part and the cooling part of the heat pump, A cold water circulation path that cools cold water in the heat absorption section and cools the fluid in the cooling section with the cold water, and a cold water pump that sends the cold water cooled in the heat absorption section to the cooling section while circulating in the cold water circulation path. And a heat exchanger in which a nutrient solution before passing through the heating section is heat-exchanged with a nutrient solution passing through the heating section in a flow path between the heating section and the cooling section, and then the heat exchanger is passed through the heating section. It is characterized by having and.

[0009]

[Action]

 With this configuration, the hot water heated by the heat radiating unit is sent to the heating unit by the hot water pump and circulates in the hot water circulation path by the above structure, and the hot water heats the nutrient solution flowing into the heating unit. Go Further, the nutrient solution before passing through the heating section is heat-exchanged with the nutrient solution passing through the heating section in the heat exchanger, and then passed through the heating section.

On the other hand, the cold water cooled in the heat absorbing part is circulated in the cold water circulation path while being sent to the cooling part by the cold water pump, and this cold water cools the heated nutrient solution flowing into the cooling part. Go

Further, the heating part of the sub-circulation path heat-sterilizes the inflowing nutrient solution, and the cooling part cools the heated nutrient solution. In the heat exchanger, the nutrient solution before passing through the heating section is heat-exchanged with the nutrient solution passing through the heating section, and then passed through the heating section.

[0012]

【Example】

 Hereinafter, an embodiment of the hydroponic cultivation apparatus according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 10 denotes a cultivation house. In the cultivation house 10, a plurality of cultivation beds 11 a to 11 n for cultivating a plant V with a nutrient solution and a nutrient solution tank 13 storing a nutrient solution 12 are provided. It is provided. The nutrient solution tank 13 and the cultivation beds 11a to 11n are communicated with each other via the flow path 14 and the switching valves J1 to Jn. The cultivation beds 11a to 11n are also connected to the nutrient solution tank 13 by the bypass path P and the switching valves J1 to Jn. Then, the pump 15 sends the nutrient solution 12 in the nutrient solution tank 13 to the cultivation beds 11a to 11n through the flow path 14 or the bypass path P and the switching valves J1 to Jn. The nutrient solution 12 sent to the cultivation beds 11a to 11n is returned to the nutrient solution tank 13 again by the flow path 16.

The flow path 14 is provided with a heating unit 20 that heat-sterilizes the nutrient solution 12 and a cooling unit 21 that cools the heated nutrient solution 12. A heat exchanger 22 heats the heated nutrient solution 12 and the unheated nutrient solution 12 flowing into the exchange coil 22a to raise the temperature of the unheated nutrient solution 12 and heat it. The temperature of the nutrient solution 12 is lowered. Then, the nutrient solution 12 whose temperature has risen in the exchange coil 22a flows into the heating section 20.

S 1 is a temperature sensor for detecting the temperature of the nutrient solution heated by the heating section 20, and S 2 is a temperature sensor for detecting the temperature of the nutrient solution cooled by the cooling section 21.

Reference numeral 30 denotes a hot water tank. The hot water tank 30 and the heater 20 a of the heating unit 20 are connected to each other by a hot water circulation path 31, and hot water of the hot water tank 30 is circulated through the hot water circulation path 31 by a hot water pump 32. It is designed to be sent to the heater 20a of the heating unit 20. In addition, the hot water tank 30 and the radiator (sub-heating unit) 33 provided in the cultivation house 10 are communicated with each other by the sub circulation path 34, and the hot water of the hot water tank 30 is radiated by the sub pump 35 while circulating through the sub circulation path 34. It is designed to be sent to the container 33. When hot water is circulated through the radiator 33, the inside of the cultivation house 10 is warmed by heat radiation. 36 is a blower fan, and S5 is a temperature sensor that detects the temperature inside the cultivation house 10.

As shown in FIG. 2, the hot water tank 30 is connected to a heat releasing portion 41 of the heat pump 40 by a communication pipe 37. The radiator 41 is provided with a condenser 41 a of the heat pump 40, and the heat released from the condenser 41 a heats the hot water flowing into the radiator 41. Reference numeral 42 denotes a hot water pump that circulates the hot water in the hot water tank 30 to the heat radiating section 41. The hot water pumped by the heat radiating section 41 is sent to the hot water tank 30 by this circulation, and the hot water in the hot water tank 30 is increased to 55 to 60 degrees. It is a thing.

Reference numeral 41b denotes a condenser connected in parallel to the heat radiating section 41. By switching the switching valve 51 to cause the refrigerant of the heat pump 40 to flow to the condenser 41b, the heat released by the condenser 41b is released to the outside air. To dissipate heat. In this case, the warm water is not heated. 52 is a blower fan.

Reference numeral 43 denotes a cold water tank. As shown in FIG. 1, the cold water tank 43 and the cooling coil 21a of the cooling unit 21 are connected to each other by a circulation path 44, and a cold water pump 45 cools the cold water of the cold water tank 43. It is adapted to be sent to the cooling coil 21a of the cooling unit 21 while circulating in the circulation path 44.

The cold water tank 43 communicates with the sub-circulation path 34 via the electromagnetic switching valve G, and the switching of the electromagnetic switching valve G circulates the cold water to the radiator 33. The circulation of the cold water causes the inside of the cultivation house 10 to be cooled. The temperature can be lowered.

As shown in FIG. 2, the cold water tank 43 is connected to a heat absorbing section 47 of the heat pump 40 by a communication pipe 46. The heat absorbing section 47 is provided with an evaporator 47a of the heat pump 40, and the cold water flowing into the heat absorbing section 47 is cooled by the heat absorption of the evaporator 47a. Reference numeral 48 denotes a cold water pump that circulates the cold water in the cold water tank 43 to the heat absorbing section 47. By this circulation, the cold water cooled in the heat absorbing section 47 is sent to the cold water tank 43, and the temperature of the cold water in the cold water tank 43 is 10 degrees Celsius or higher. It is set to 15 degrees.

Reference numeral 47b denotes an evaporator connected in parallel to the heat absorbing portion 47, which absorbs heat from the outside air by flowing the refrigerant of the heat pump 40 to the evaporator 47b by switching the electromagnetic switching valve 49. In this case, cooling of cold water is not performed. 50 is a blower fan.

Reference numeral 53 is a pressure reducing valve, 54 is a liquid receiver, 55 is a compressor, S3 is a hot water sensor for detecting the temperature of hot water in a hot water tank, and S4 is a cold water sensor for detecting the temperature of cooling water.

FIG. 3 shows that the pumps 15, 32, 35, 42, 45, 48 and the electromagnetic switching valves 49, 51, G, J1, J2 ... Jn are based on the temperatures detected by the respective sensors S1 to S5. FIG. 3 is a block diagram showing the configuration of a control system for controlling the

In FIG. 3, reference numeral 60 denotes a control device including a microcomputer, which controls the hot water pump 32 and the cold water pump 45 so that the temperatures detected by the sensors S1 and S2 are 50 degrees and 20 degrees, respectively. Adjust the circulating hot water volume and cold water volume.

Further, the control device 60 switches the electromagnetic switching valves 51 and 49 so that the temperatures detected by the sensors S3 and S4 are 55 degrees to 60 degrees and 10 degrees to 15 degrees. Furthermore, the control device 60 switches the electromagnetic switching valve G and controls the pump 35 based on the temperature detected by the sensor S5 to bring the inside of the cultivation house 10 to a predetermined temperature, and controls the switching valves J1 to Jn. The nutrient solution that is heat-sterilized by controlling the switching or the nutrient solution 12 directly in the nutrient solution tank 13 is caused to flow to the cultivation beds 11a to 11n.

Next, the operation of the heat sterilizer of the embodiment configured as described above will be described.

First, the heat pump 40 and the pumps 42 and 48 are operated to increase the hot water in the hot water tank 21 to 55 to 60 degrees and cool the cold water in the cold water tank to 10 to 15 degrees. After that, the hot water pump 32 and the cold water pump 45 are operated to circulate the hot water in the hot water tank 30 to the heater 20a of the heating unit 20 and circulate the cold water in the cold water tank 43 to the cooling coil 21a of the cooling unit 21. Circulate.

On the other hand, the switching valve J1 is switched to connect the flow path 14 and the cultivation bed 11a, and the pump 15 is operated to cause the nutrient solution 12 in the nutrient solution tank 13 to flow into the flow path 14a. On the other hand, since the cultivation beds 11b to 11n are in communication with the bypass passage P by the switching valves J2 to Jn, the nutrient solution 12 in the nutrient solution tank 13 flows into the cultivation beds 11b to 11n via the bypass passage P.

The nutrient solution 12 that has flowed into the flow path 14 a flows into the heating section 20 via the exchange coil 22 a of the heat exchanger 22. In the heating unit 20, the nutrient solution is heated by the heater 20a. The heated nutrient solution flows into the heat exchanger 22 and is heat-exchanged with the nutrient solution passing through the exchange coil 22a.

The nutrient solution passing through the exchange coil 22a is heated to about 40 degrees and flows into the heating section 20, and is heated to 50 degrees by the heater 20a to be sterilized. The sterilized nutrient solution is heat-exchanged by the heat exchanger 22 and its temperature is lowered. The nutrient solution having the lowered temperature flows into the cooling section 21 and is cooled to 20 degrees by the cooling coil 21a. The cooled nutrient solution 12 flows into the cultivation bed 11a via the switching valve J1.

By the way, since the nutrient solution heated by the heater 20a of the heating unit 20 is heated to about 40 degrees by the heat exchanger 22, the amount of heat required for heating up to the temperature of 50 degrees for heat sterilization is small. It does not require high power to heat. Further, since the temperature of the nutrient solution cooled by the cooling unit 21 is lowered by the heat exchanger 22, it does not require a large electric power to cool it to 20 degrees. Therefore, the heat pump 40 may be a small one for small electric power. By the way, compared with the case where the heat exchanger 22 is not used, it may be for a small electric power of about 1/3 or less.

Further, for example, when the temperature of the nutrient solution cooled in the cooling unit 21 becomes higher than 20 degrees, the control device 60 increases the rotational force of the cold water pump 45 to increase the amount of cold water flowing to the cooling coil 21a. Allow the nutrient solution to cool to 20 degrees. At this time, since the control device 60 only increases the rotational force of the cold water pump 45, it has no effect on the heating of the heating unit 20.

On the contrary, when the temperature of the nutrient solution heated by the heating unit 20 becomes 50 degrees or less, the controller 60 increases the rotating force of the warm water pump 32 to increase the amount of warm water flowing to the heater 20a. The temperature is maintained at 50 degrees. At this time as well, the control device 60 only increases the rotational force of the hot water pump 32, and therefore has no effect on the cooling of the cooling unit 21.

As described above, since the temperature control of the heating unit 20 and the temperature control of the cooling unit 21 can be performed independently of each other, the temperature control can be easily performed.

When the temperature of the cold water in the cold water tank 43 falls within the range of 10 to 15 degrees and the temperature of the hot water in the hot water tank 21 drops to 55 degrees or lower, the heat pump 40 performs the heating only operation. That is, the electromagnetic switching valve 51 is switched to cause the refrigerant to flow into the condenser 41a, and the condenser 41a radiates heat to the hot water to raise the temperature of the hot water in the hot water tank 30 from 55 degrees. At this time, the refrigerant that has passed through the condenser 41a and has been cooled is decompressed and expanded by passing through the pressure reducing valve 53, and then is made to flow to the evaporator 47b by the electromagnetic switching valve 49 and the blower fan 50 is driven. The evaporator 47b absorbs heat into the outside air to evaporate the refrigerant. Then, the evaporated refrigerant is sent to the compressor 45.

When the hot water temperature of the hot water tank 30 exceeds 60 degrees, the operation of the heat pump 40 is stopped. Thereby, the hot water temperature of the hot water tank 30 can be lowered to 55 to 60 degrees while keeping the cold water temperature of the cold water tank 43 at 10 to 15 degrees.

On the contrary, when the temperature of the hot water in the hot water tank 30 is within the range of 55 to 60 degrees and the temperature of the cold water in the cold water tank 43 rises to 15 degrees or more, the heat pump 40 performs the cooling independent operation. .. That is, the electromagnetic switching valve 51 is switched to flow the refrigerant to the condenser 41b, and at the same time, the blower fan 52 is driven to radiate the heat of the condenser 41b to the outside air to prevent the temperature rise of the hot water in the hot water tank 30. At this time, the refrigerant that has passed through the condenser 41b and cooled is decompressed and expanded by passing through the pressure reducing valve 53, and then is made to flow to the evaporator 47a by the electromagnetic switching valve 49 and absorbs heat from the cold water at the evaporator 47a. To evaporate the refrigerant. Then, the evaporated refrigerant is sent to the compressor 55. As a result, the cold water in the cold water tank 43 is only cooled.

When the cold water temperature of the cold water tank 43 becomes 10 degrees or lower, the operation of the heat pump 40 is stopped. As a result, the cold water temperature of the cold water tank 43 can be raised to 10 to 15 degrees while keeping the hot water temperature of the hot water tank 30 at 55 to 60 degrees.

When the temperature of the hot water in the hot water tank 30 drops to 55 degrees or lower, and when the temperature of the cold water in the cooling tank 43 rises to 15 degrees or higher, the heat pump 40 performs the heating / cooling simultaneous operation. That is, the temperature of the hot water in the hot water tank 30 is raised to 55 to 60 degrees by switching the electromagnetic switching valve 51 to flow the refrigerant into the condenser 41a and radiate the heat to the hot water in the condenser 41a.

At this time, the refrigerant that has passed through the condenser 41 a and is cooled is passed through the pressure reducing valve 53 to be depressurized / expanded, and this refrigerant is made to flow to the evaporator 47 a by the electromagnetic valve 49. Then, the evaporator 47a absorbs heat from the cold water to evaporate the refrigerant. Thereby, the cold water in the cold water tank 43 is cooled, and the temperature of the cold water is cooled to 10 to 15 degrees. The evaporated refrigerant is sent to the compressor 55.

When the cold water temperature of the cold water tank 43 drops below 10 degrees, the electromagnetic switching valve 49 is switched to allow the refrigerant to flow to the evaporator 47b, and the heat pump 40 is moved to the independent heating operation.

On the contrary, when the temperature of the hot water in the hot water tank 30 exceeds 60 degrees, the electromagnetic switching valve 51 is switched to allow the refrigerant to flow to the condenser 41b, and the heat pump 40 is shifted to the independent cooling operation.

As described above, since heating and cooling can be performed at the same time by operating one heat pump 40, efficient operation is possible and energy consumption of input power can be reduced.

The hot water in the hot water tank 30 is sent to the radiator 33 provided in the cultivation house 10 by the pump 35, and the inside of the cultivation house 10 is maintained at a predetermined temperature. When the temperature detected by the sensor S5 is high and cooling must be performed in the cultivation house 10, the control device 60 switches the electromagnetic switching valve G to send cold water to the radiator 33. As a result, the temperature inside the cultivation house 10 is lowered and maintained at a predetermined temperature.

As described above, since the heat radiation and the heat absorption of the heat pump 40 are used for cooling and heating the cultivation house 10, the heat can be effectively used. In addition, it is very convenient because hot water or cold water can be supplied to other places simply by drawing a pipe from the hot water tank 30 or the cold water tank 43.

When the cultivation bed 11a is filled with the sterilized nutrient solution 12, the switching valve J1 is switched to the original state and the switching valve J2 is switched to connect the cultivation bed 11b and the flow path 14 to each other. Then, in the same manner as above, the sterilized nutrient solution 12 is poured into the cultivation bed 11b.

FIG. 4 shows another embodiment. In this embodiment, a sub-circulation path 70 different from the circulation path 60 for circulating the nutrient solution is provided in the cultivation beds 11a to 11n, and the sub-circulation path 70 is provided with a heating unit 20 for heat-sterilizing the nutrient solution and the nutrient solution. A cooling unit 21 for cooling and a heat exchanger 22 between the heating unit 20 and the cooling unit 21 are provided, and the nutrient solution in the nutrient solution tank 13 is circulated to the auxiliary circulation path 70 by the pump 71 for sterilization. The sterilized nutrient solution is returned to the nutrient solution tank 13.

According to this embodiment, since the switching valve J and the bypass passage P are unnecessary and the distance of the flow passage 14 can be shortened, the facility cost can be reduced.

In each of the above embodiments, a one-stage compression heat pump is used. However, for example, as shown in FIG. 5, a two-stage compression heat pump or a two-stage compression heat pump which is performed by two heat pumps may be used. For example, it is possible to set the heat sterilization temperature to 60 degrees or higher.

[0051]

【effect】

 As described above, the present invention is provided with the hot water circulation path, the cold water circulation path, the heat exchanger, etc., so that the heat pump has about 1/3 or less of the heat pump compared to the case where the heat exchanger is not installed. It may be for a small electric power, and the temperature control of the heating part and the temperature control of the cooling part can be performed independently of each other, so that the temperature control can be easily performed. Moreover, since the hot water is circulated in the sub-heating section, the heat can be effectively used.

[Brief description of drawings]

FIG. 1 is a block diagram schematically showing the configuration of a hydroponics device according to the present invention,

FIG. 2 is a block diagram schematically showing the configuration of a heat pump,

FIG. 3 is a block diagram showing the configuration of a control system of the hydroponic cultivation device,

FIG. 4 is an explanatory diagram showing the configuration of another embodiment,

FIG. 5 is an explanatory diagram showing a configuration of a two-stage compression heat pump,

FIG. 6 is an explanatory diagram showing a configuration of a conventional hydroponics device.

[Explanation of symbols]

 11a-11n Cultivation bed 12 Nutrient solution 14 Flow path 20 Heating part 21 Cooling part 22 Heat exchanger 31 Hot water circulation path 32 Hot water pump 40 Heat pump 41 Heat dissipation part 44 Cold water circulation path 45 Cold water pump

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kunihiro Amimoto 2086-4 Ono, Kagawa-cho, Kagawa-gun, Kagawa Prefecture

Claims (4)

[Scope of utility model registration request] 1. A hydroponic bed for cultivating a plant with a nutrient solution, a nutrient solution tank for storing the nutrient solution, and a flow path for allowing the nutrient solution in the nutrient solution to flow into the nutrient solution bed. In this flow path, a heating unit for heating and sterilizing the nutrient solution and a cooling unit for cooling the heated nutrient solution are provided, and the nutrient solution for heating the heating unit and cooling the cooling unit with a heat pump. A cultivating device, wherein hot water circulates through the heat radiating portion and the heating portion of the heat pump, heats the hot water at the heat radiating portion, and heats the nutrient solution flowing into the heating portion with the hot water. A hot water pump that sends hot water heated in the heat radiating unit to the heating unit while circulating the hot water in the hot water circulation path; Cold water that cools and cools the fluid in the cooling section with the cold water A circulation path, a cold water pump that sends cold water cooled in the heat absorption section to the cooling section while circulating the cold water in the cold water circulation path, a flow path between the heating section and the cooling section, before passing through the heating section. And a heat exchanger for passing the nutrient solution of (1) to the nutrient solution that has passed through the heating section, and then passing the heat through the heating section. 2. A hot water tank for storing hot water heated by the heat radiating section, and a cold water tank for storing cold water cooled by the heat absorbing section, wherein the hot water pump circulates the hot water in the hot water tank and the cold water pump. Is circulated by cold water in a cold water tank. 3. A sub-heating unit that heats something other than the fluid, a sub-hot water circulation path that circulates the sub-heating unit and the heat radiating unit of the heat pump, and hot water that is heated in the heat radiating unit. The submerged water pump which circulates in a circulation path was provided, The hydroponics device of Claim 1 characterized by the above-mentioned. 4. A hydroponic bed for cultivating plants with a nutrient solution, a nutrient solution tank for storing the nutrient solution, and a circulation path for circulating the nutrient solution in the nutrient solution to the nutrient solution bed. A sub-circulation that has a heating unit that heats and sterilizes the nutrient solution by flowing it into the nutrient solution tank and a cooling unit that cools the heated nutrient solution, and returns the nutrient solution that has passed through the cooling section to the nutrient solution tank. A hydroponic cultivation apparatus comprising a passage and performing heating of the heating section and cooling of the cooling section by a heat pump, in which hot water circulates between the heat radiating section and the heating section of the heat pump, and the hot water is heated by the heat radiating section. A hot water circulation path for heating the nutrient solution flowing into the heating section with the hot water, and a hot water pump for sending the hot water heated by the heat radiation section to the heating section while circulating the hot water in the hot water circulation path, Cold water circulates between the heat absorption part of the heat pump and the cooling part, and at the heat absorption part A cold water circulation path for cooling water and cooling the fluid in the cooling section with the cold water; a cold water pump for sending the cold water cooled by the heat absorbing section to the cooling section while circulating the cold water in the cold water circulation path; and the heating section. And a heat exchanger that allows the nutrient solution before passing through the heating section to exchange heat with the nutrient solution that passes through the heating section and then through the heating section in the flow path between the heating section and the cooling section. Hydroponics device characterized by.