JP6560950B2 - Plant growth promotion device - Google Patents

Description

  The present invention relates to a plant growth promotion device that promotes plant growth.

Generally, when cultivating plants such as crops such as vegetables and fruits, horticultural plants such as flower buds and foliage plants in a greenhouse, carbon dioxide is supplied into the greenhouse to promote photosynthesis of the plants. Exhaust gas generated by combustion is widely used as carbon dioxide to be supplied to a greenhouse. For example, Patent Document 1 discloses nitrogen that was thought to inhibit plant growth from exhaust gas generated in a thermal power generation facility. A configuration in which oxide (NO _x ) is removed and supplied to a greenhouse is described.

  Thus, conventionally, nitrogen oxides were thought to inhibit plant growth. However, according to recent research, the plant growth atmosphere is changed to a nitrogen oxide atmosphere of 10 ppb to 200 ppb. (For example, Non-patent Document 1 and Patent Document 2).

Japanese Patent No. 4499536 JP 2012-235748 A

Plant Signaling & Behavior 9, e28563; March; 2014

  As described in Patent Document 2, the atmosphere of nitrogen oxides in a predetermined concentration range can promote plant growth. Therefore, development of a technique for growing plants more efficiently using nitrogen oxides. Is sought after.

  In view of such a problem, an object of the present invention is to provide a plant growth promoting apparatus that can grow plants efficiently.

In order to solve the above-described problems, a plant growth promotion device according to the present invention is a plant growth promotion device that promotes plant growth, and generates a mixed gas containing carbon dioxide and nitrogen oxides by burning fuel. Combustion unit, supply amount control unit for controlling the supply amount of fuel to the combustion unit, and the concentration of nitrogen oxide in the atmosphere of the cultivation area is maintained at a predetermined nitrogen oxide target value, An air ratio control unit that controls an air ratio of the combustion unit; and a supply unit that supplies the mixed gas generated by the combustion unit to a plant cultivation site. The nitrogen oxide concentration in the atmosphere is maintained at the first nitrogen oxide target value until a predetermined period has elapsed after sowing, and after the predetermined period has elapsed, the nitrogen oxide concentration is less than the first nitrogen oxide target value. The second nitrogen oxide target value is maintained .

  The supply amount control unit may control the supply amount of the fuel such that the concentration of carbon dioxide in the atmosphere of the cultivation area is maintained at a predetermined carbon dioxide target value.

  In addition, an operation mode selection unit that selects one operation mode from a plurality of operation modes according to an operation input by an operator is provided, and at least the carbon dioxide target value is a first carbon dioxide in the plurality of operation modes. An operation mode in which the nitrogen oxide target value is set to the first nitrogen oxide target value, and the carbon dioxide target value is set to a second carbon dioxide target value less than the first carbon dioxide target value. And an operation mode in which the nitrogen oxide target value is set to the first nitrogen oxide target value.

  According to the present invention, it becomes possible to grow plants efficiently.

It is a figure explaining a plant growth promotion apparatus. It is a flowchart explaining the flow of a process of a plant cultivation method. It is a flowchart explaining the flow of a 1st operation mode process. It is a flowchart explaining the flow of a 2nd operation mode process. It is a flowchart explaining the flow of a 3rd operation mode process.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Plant growth promotion apparatus 100)
FIG. 1 is a diagram for explaining a plant growth promoting apparatus 100. As shown in FIG. 1, the plant growth promotion apparatus 100 according to this embodiment includes a combustion unit 110, a supply unit 120, a first concentration measurement unit 130, a second concentration measurement unit 140, and a central control unit 150. The mixed gas containing carbon dioxide (CO ₂ ) and nitrogen oxide (NO _x ) is generated and supplied to the greenhouse 10 where the plant 12 is grown. In FIG. 1, the signal flow is indicated by broken arrows. Here, nitrogen dioxide (NO ₂ ) will be described as an example of nitrogen oxide.

  The combustion unit 110 includes a combustion unit 112, a fuel supply unit 114, and an air supply unit 116.

  The combustion unit 112 is constituted by, for example, a burner, and burns the fuel supplied by the fuel supply unit 114 with the air supplied by the air supply unit 116 to generate a mixed gas.

  The fuel supply unit 114 is configured by a pump, for example, and supplies fuel from a fuel supply source (not shown) to the combustion unit 112. A flow rate adjusting valve 114 a is provided between the fuel supply unit 114 and the combustion unit 112.

  The air supply unit 116 is configured by a blower, for example, and supplies air to the combustion unit 112. A flow rate adjusting valve 116 a is provided between the air supply unit 116 and the combustion unit 112.

  The supply unit 120 is configured by a fan, for example, and blows the mixed gas generated by the combustion unit 110 into the greenhouse 10.

The first concentration measuring unit 130 is based on one or a plurality of measuring probes 132 arranged in the greenhouse 10 and a signal input from the measuring probe 132 in the atmosphere in the greenhouse 10 (in the atmosphere of the cultivation area). And a first concentration measuring unit 134 that measures the concentration of nitrogen oxides. In the present embodiment, the first concentration measurement unit 130 measures the concentration of NO ₂ as nitrogen oxides. Since the measurement of nitrogen oxides by the first concentration measurement unit 130 is an existing technique, detailed description thereof is omitted here.

The second concentration measuring unit 140 is based on one or a plurality of measuring probes 142 arranged in the greenhouse 10 and a signal input from the measuring probe 142 in the atmosphere in the greenhouse 10 (in the atmosphere of the cultivation area). And a second concentration measuring unit 144 that measures the concentration of CO ₂ . Since the measurement of CO ₂ by the second concentration measurement unit 140 is an existing technique, detailed description thereof is omitted here.

  The central control unit 150 is composed of a semiconductor integrated circuit including a CPU (central processing unit), reads a program, parameters, and the like for operating the CPU itself from a ROM, and cooperates with a RAM as a work area and other electronic circuits. Then, the whole plant growth promotion apparatus 100 is managed and controlled. In the present embodiment, the central control unit 150 functions as an operation mode selection unit 152, a supply amount control unit 154, and an air ratio control unit 156.

The operation mode selection unit 152 selects one operation mode from the three operation modes in accordance with an operation input by the operator. The supply amount control unit 154 controls the amount of fuel supplied to the combustion unit 112 according to the conditions set in the operation mode selected by the operation mode selection unit 152. The air ratio control unit 156 is configured to increase or decrease the amount of NO ₂ generated by the combustion unit 112 according to the conditions set in the operation mode selected by the operation mode selection unit 152. Air / fuel ratio) is controlled. Although specifically described later, the supply amount control unit 154 increases the amount of CO ₂ generated by combustion by increasing the supply amount of fuel to the combustion unit 112 and increases the concentration of CO ₂ in the greenhouse 10. Let Further, in a state in which the supply amount control unit 154 maintains the fuel supply amount to the combustion unit 112 at a predetermined value, the air ratio control unit 156 controls the amount of air supplied to the combustion unit 112 to control NO in the greenhouse 10. ₂ Control the concentration. For example, the concentration of NO ₂ is increased by increasing the air ratio, or the concentration of NO ₂ is decreased by decreasing the air ratio. Here, the supply amount of fuel is, for example, the standard volume of fuel per unit time, and the air ratio is the amount of air for combustion / theoretical air amount (the minimum amount of air necessary for completely burning the fuel). ). Hereinafter, each of the three operation modes will be described.

(First operation mode)
The first operation mode is an operation mode in which the concentration of CO ₂ in the greenhouse 10 is the first carbon dioxide target value. The first carbon dioxide target value is a value that is determined according to the type of the plant 12 and that promotes the growth of the plant 12 over the air environment, and is determined in advance within a range of 400 ppm to 2000 ppm, for example. Value.

More specifically, when the first operation mode is selected by the operation mode selection unit 152, the supply amount control unit 154 first determines that the CO ₂ concentration measured by the second concentration measurement unit 140 is the first concentration. The amount of fuel supplied to the combustion unit 112 is controlled by adjusting the opening of the flow rate adjustment valve 114a so as to be a carbon dioxide target value (for example, 1000 ppm).

Based on the fuel supply amount determined by the supply amount control unit 154, the air ratio control unit 156 generates an air ratio (NO ₂ measured by the first concentration measurement unit 130) such that NO ₂ is not generated as much as possible. The opening degree of the flow rate adjustment valve 116a is adjusted so that the concentration becomes an air ratio (for example, theoretical air amount) that becomes a predetermined second nitrogen oxide target value lower than a first nitrogen oxide target value described later.

Thereby, the inside of the greenhouse 10 can be maintained in a CO ₂ atmosphere that promotes the growth of the plant 12, and the plant 12 can be efficiently grown.

(Second operation mode)
The second operation mode is an operation mode in which the concentration of CO ₂ in the greenhouse 10 is set to the second carbon dioxide target value less than the first carbon dioxide target value, and the concentration of NO ₂ is set to the first nitrogen oxide target value. It is. In addition, a 1st nitrogen oxide target value is a value determined according to the kind of plant 12, and is a value which accelerates | stimulates the growth of the said plant 12, for example, is a predetermined value in the range of 5 ppb-1000 ppb. .

More specifically, when the second operation mode is selected by the operation mode selection unit 152, the supply amount control unit 154 first determines that the CO ₂ concentration measured by the second concentration measurement unit 140 is the second concentration. The amount of fuel supplied to the combustion unit 112 is controlled by adjusting the opening of the flow rate adjustment valve 114a so as to be a carbon dioxide target value (for example, 600 ppm).

The air ratio control unit 156 adjusts the opening degree of the flow rate adjustment valve 116a so that the NO ₂ concentration measured by the first concentration measurement unit 130 becomes the first nitrogen oxide target value (for example, 50 ppb). The air ratio of the combustion unit 112 is controlled. More specifically, the air ratio control unit 156 includes the fuel supply amount determined by the supply amount control unit 154 and the target air ratio (the measured value of the first concentration measurement unit 130 is the first nitrogen oxide target). The air ratio of the combustion unit 112 is controlled by adjusting the opening degree of the flow rate adjusting valve 116a based on the air ratio.

As described above, in the second operation mode, the fuel supply amount is controlled so that the CO ₂ concentration in the atmosphere of the greenhouse 10 is maintained at the second carbon dioxide target value lower than the first carbon dioxide target value. The air ratio is controlled so that the concentration of NO _{2 in} the atmosphere of the greenhouse 10 is maintained at the first nitrogen oxide target value. Therefore, if the lower limit value of the carbon dioxide concentration that promotes the growth of the plant 12 is set to the second carbon dioxide target value, the fuel that can secure the minimum CO ₂ necessary for promoting the growth of the plant 12 is burned. However, the concentration of NO ₂ can be maintained at the first nitrogen oxide target value.

  Thereby, it becomes possible to maintain the inside of the greenhouse 10 in an atmosphere that promotes the growth of the plant 12 while reducing fuel consumption as compared with the first operation mode. Therefore, it becomes possible to promote the growth of the plant 12 at a low cost, and the plant 12 can be efficiently grown.

(Third operation mode)
The third operation mode is an operation mode in which the concentration of CO ₂ in the greenhouse 10 is set as the first carbon dioxide target value, and the concentration of NO ₂ is set as the first nitrogen oxide target value.

More specifically, when the third operation mode is selected by the operation mode selection unit 152, the supply amount control unit 154 first determines that the CO ₂ concentration measured by the second concentration measurement unit 140 is the first dioxide concentration. The amount of fuel supplied to the combustion unit 112 is controlled by adjusting the opening of the flow rate adjustment valve 114a so as to be the carbon target value.

The air ratio control unit 156 adjusts the opening of the flow rate adjustment valve 116a so that the concentration of NO ₂ measured by the first concentration measurement unit 130 becomes the first nitrogen oxide target value, and Control the air ratio.

Thus, in the third operation mode, the fuel supply amount is controlled so that the concentration of CO _{2 in} the atmosphere of the greenhouse 10 is maintained at the first carbon dioxide target value, and NO in the atmosphere of the greenhouse 10 is maintained. _The air ratio is controlled so that the concentration of ₂ is maintained at the first nitrogen oxide target value.

Thereby, the inside of the greenhouse 10 can be maintained in an atmosphere that further promotes the growth of the plant 12, and the plant 12 can be efficiently grown. In the third operation mode, the fuel consumption per unit time is increased as compared with the second operation mode, but the effect of promoting the growth of the plant 12 can be improved. Therefore, it is possible to shorten the period until the plant 12 is grown (for example, the period during which the yield of the plant 12 is substantially equal) as in the case of growing in the second operation mode. Thus, since the period for supplying CO ₂ and NO ₂ can be shortened, the atmosphere for promoting the growth of the plant 12 in the greenhouse 10 while reducing the consumed fuel as compared with the first operation mode. Can be maintained.

  As described above, the operation mode selection unit 152 can select at least the second operation mode or the third operation mode, so that the fuel consumption can be reduced. If it demonstrates concretely, the growth promotion effect of the plant 12 by a nitrogen oxide will be especially exhibited in the initial stage of the growth of the plant 12 until a predetermined period passes after sowing. Therefore, in the initial stage of plant 12 growth, by selecting the second operation mode, the same cultivation period as the first operation mode (conventional carbon dioxide fertilization) and the growth of the same plant 12 (same yield). The fuel consumption can be reduced. In addition, by selecting the third operation mode in the initial stage of growing the plant 12, the plant 12 has the same cultivation period and the same amount of fuel consumption as the first operation mode (conventional carbon dioxide fertilization). It is possible to promote (increased sales) training. Further, by selecting the third operation mode, even if the plant 12 is grown with the same amount of fuel consumption as that in the first operation mode (conventional carbon dioxide fertilization), the plant 12 is grown in the same manner as in the past. The cultivation period can be shortened.

  As described above, according to the plant growth promotion apparatus 100 according to the present embodiment, the inside of the greenhouse 10 can be maintained in an atmosphere that promotes the growth of the plant 12, and the plant 12 can be efficiently grown. Become.

(Plant cultivation method)
Then, the plant cultivation method using the plant growth promotion apparatus 100 is demonstrated. FIG. 2 is a flowchart for explaining the flow of the plant cultivation method. In the plant growth promotion device 100, the first concentration measurement unit 130 constantly monitors the concentration of NO ₂ , and the second concentration measurement unit 140 constantly monitors the concentration of CO ₂ , and the process shown in the flowchart of FIG. This is executed as an interrupt process at predetermined time intervals.

(Step S210)
The central control unit 150 determines whether or not the operation mode is the first operation mode. As a result, when it is determined that the operation mode is the first operation mode, the process proceeds to step S220. When it is determined that the operation mode is not the first operation mode, the process proceeds to step S230.

(Step S220)
The central control unit 150 performs the first operation mode process and ends the process according to the plant cultivation method. The first operation mode process will be described later in detail.

(Step S230)
The central control unit 150 determines whether or not the operation mode is the second operation mode. As a result, when it is determined that the operation mode is the second operation mode, the process proceeds to step S240, and when it is determined that the operation mode is not the second operation mode, the process proceeds to step S250.

(Step S240)
The central control unit 150 performs the second operation mode process and ends the process according to the plant cultivation method. This second operation mode process will be described in detail later.

(Step S250)
The central control unit 150 performs the third operation mode process and ends the process according to the plant cultivation method. This third operation mode process will be described in detail later.

  FIG. 3 is a flowchart for explaining the flow of the first operation mode process (step S220).

(Step S220-1)
The supply amount control unit 154 determines whether or not the CO ₂ concentration (measured value D) measured by the second concentration measuring unit 140 is less than the first carbon dioxide target value D1. As a result, if it is determined that the measured value D is less than the first carbon dioxide target value D1, the process proceeds to step S220-3, and it is determined that the measured value D is not less than the first carbon dioxide target value D1. In that case, the process proceeds to step S220-5.

(Step S220-3)
The supply amount control unit 154 increases the opening degree of the flow rate adjustment valve 114a, and moves the process to step S220-9.

(Step S220-5)
The supply amount control unit 154 determines whether or not the measured value D exceeds the first carbon dioxide target value D1. As a result, if it is determined that the measured value D exceeds the first carbon dioxide target value D1, the process proceeds to step S220-7, and the measured value D does not exceed the first carbon dioxide target value D1. If so, the process moves to step S220-9.

(Step S220-7)
The supply amount control unit 154 decreases the opening degree of the flow rate adjustment valve 114a, and moves the process to step S220-9.

(Step S220-9)
The air ratio control unit 156 is configured to generate air that does not generate NO ₂ as much as possible based on the fuel supply amount according to the opening degree of the flow rate adjustment valve 114a determined in step S220-3 or step S220-7. An air ratio control process for adjusting the opening degree of the flow rate adjustment valve 116a so as to achieve the ratio is performed, and the first operation mode process ends. Here, the air ratio at which NO ₂ is not generated as much as possible is, for example, an air ratio that substantially realizes stoichiometric combustion, or an air ratio that is lean enough to sufficiently reduce the combustion temperature.

Thus, the mixed gas is supplied into the greenhouse 10 so that the inside of the greenhouse 10 has a CO ₂ atmosphere that promotes the growth of the plant 12.

  FIG. 4 is a flowchart for explaining the flow of the second operation mode process (step S240).

(Step S240-1)
The supply amount control unit 154 determines whether or not the measured value D is less than the second carbon dioxide target value D2. As a result, when it is determined that the measured value D is less than the second carbon dioxide target value D2, the process proceeds to step S240-3, and it is determined that the measured value D is not less than the second carbon dioxide target value D2. In that case, the process proceeds to step S240-5.

(Step S240-3)
The supply amount control unit 154 increases the opening degree of the flow rate adjustment valve 114a, and moves the process to step S240-9.

(Step S240-5)
The supply amount control unit 154 determines whether or not the measured value D exceeds the second carbon dioxide target value D2. As a result, when it is determined that the measured value D exceeds the second carbon dioxide target value D2, the process proceeds to step S240-7, and the measured value D does not exceed the second carbon dioxide target value D2. If so, the process moves to step S240-9.

(Step S240-7)
The supply amount control unit 154 decreases the opening degree of the flow rate adjustment valve 114a, and moves the process to step S240-9.

(Step S240-9)
The air ratio control unit 156 determines whether or not the NO ₂ concentration (measured value C) measured by the first concentration measuring unit 130 is less than the first nitrogen oxide target value C1. As a result, when it is determined that the measured value C is less than the first nitrogen oxide target value C1, the process proceeds to step S240-11, and the measured value C is not less than the first nitrogen oxide target value C1. If so, the process moves to step S240-13.

(Step S240-11)
The air ratio control unit 156 increases the opening of the flow rate adjustment valve 116a, and ends the second operation mode process.

(Step S240-13)
The air ratio control unit 156 determines whether or not the measured value C exceeds the first nitrogen oxide target value C1. As a result, when it is determined that the measured value C exceeds the first nitrogen oxide target value C1, the process proceeds to step S240-15, and the measured value C exceeds the first nitrogen oxide target value C1. If it is determined that there is no, the second operation mode process is terminated.

(Step S240-15)
The air ratio control unit 156 decreases the opening degree of the flow rate adjustment valve 116a and ends the second operation mode process.

  Thus, the mixed gas is supplied into the greenhouse 10 so that the inside of the greenhouse 10 has an atmosphere that promotes the growth of the plant 12.

  FIG. 5 is a flowchart for explaining the flow of the third operation mode process (step S250).

(Step S250-1)
The supply amount control unit 154 determines whether or not the measured value D is less than the first carbon dioxide target value D1. As a result, if it is determined that the measured value D is less than the first carbon dioxide target value D1, the process proceeds to step S250-3, and it is determined that the measured value D is not less than the first carbon dioxide target value D1. In that case, the process proceeds to step S250-5.

(Step S250-3)
The supply amount control unit 154 increases the opening degree of the flow rate adjustment valve 114a, and moves the process to step S250-9.

(Step S250-5)
The supply amount control unit 154 determines whether or not the measured value D exceeds the first carbon dioxide target value D1. As a result, when it is determined that the measured value D exceeds the first carbon dioxide target value D1, the process proceeds to step S250-7, and the measured value D does not exceed the first carbon dioxide target value D1. If so, the process moves to step S250-9.

(Step S250-7)
The supply amount control unit 154 reduces the opening degree of the flow rate adjustment valve 114a, and moves the process to step S250-9.

(Step S250-9)
The air ratio control unit 156 determines whether or not the NO ₂ concentration (measured value C) measured by the first concentration measuring unit 130 is less than the first nitrogen oxide target value C1. As a result, when it is determined that the measured value C is less than the first nitrogen oxide target value C1, the process proceeds to step S250-11, and the measured value C is not less than the first nitrogen oxide target value C1. If so, the process moves to step S250-13.

(Step S250-11)
The air ratio control unit 156 increases the opening of the flow rate adjustment valve 116a and ends the third operation mode process.

(Step S250-13)
The air ratio control unit 156 determines whether or not the measured value C exceeds the first nitrogen oxide target value C1. As a result, when it is determined that the measured value C exceeds the first nitrogen oxide target value C1, the process proceeds to step S250-15, and the measured value C exceeds the first nitrogen oxide target value C1. If it is determined that there is no, the third operation mode process is terminated.

(Step S250-15)
The air ratio control unit 156 decreases the opening degree of the flow rate adjustment valve 116a and ends the third operation mode process.

  Thus, the mixed gas is supplied into the greenhouse 10 so that the inside of the greenhouse 10 has an atmosphere that promotes the growth of the plant 12.

(Example)
Lettuce (variety names: Anoma, Tojonmatto, Redfire), spinach (variety names: Okame, Jiro Marukusa), Japanese radish (variety name: Comet), Hiroshimana, tomato (variety name: Microtom), cucumber (variety name) : Hayami Midori) were grown in the first operation mode and the second operation mode, and the dry weight after harvesting was compared. In the first operation mode, the carbon dioxide target value was set to 1000 ppm, and NO ₂ was cultivated in the same manner as the atmospheric environment (3 ppb). In the second operation mode, cultivation was performed with the lower limit value of the carbon dioxide target range set to 600 ppm and the nitrogen oxide target value set to 50 ppb.

  As a result, in any of the nine types of plants, no significant difference was observed in the dry weight of biomass (harvest) obtained as a result of cultivation in the first operation mode and the second operation mode.

  From the above, Asterales such as lettuce, Asteraceae, plants of the genus Lactica, Caryophyllales such as spinach, Amaranthaceae, Chenopodioideae, Plants of the genus Spina, Brassicaes such as radish, Brassicaceae, Raphanus plants, Brassices such as Hiroshima, Brassicaceae plants, tomatoes, etc. The concentration of carbon dioxide in the plants of Solanales, Solanaceae, Solanum, Cucurbitales such as cucumber, Cucurbitaceae, and Cucumis It was confirmed that by optimizing the concentration of nitrogen oxides, the yield similar to that obtained when the concentration of carbon dioxide was optimized could be obtained even if the lower limit was maintained. It was.

  Thereby, it turned out that a plant can be raised efficiently, reducing the fuel to consume.

  From the above results, it is estimated that the plant 12 can be grown more efficiently by optimizing both the concentration of carbon dioxide and the concentration of nitrogen oxides in the atmosphere in the greenhouse 10.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

For example, in the above-described embodiment, NO ₂ has been described as an example of the nitrogen oxide generated by the combustion unit 112, but the type of nitrogen oxide generated by the combustion unit 112 is not limited. For example, nitric oxide (NO), dinitrogen monoxide (N ₂ O), dinitrogen trioxide (N ₂ O ₃ ), dinitrogen tetroxide (N ₂ O ₄ ), dinitrogen pentoxide (N ₂ O ₅₎ It may be one type of nitrogen oxide other than NO ₂ such as), or a mixture of a plurality of types of nitrogen oxides.

In the above embodiment, since it has been described by taking the combustion portion 112 for generating NO ₂ as an example, the first concentration measurement unit 130 has been described as an example an arrangement for measuring the concentration of NO _2. However, the first concentration measurement unit 130 may measure the concentration of nitrogen oxides generated by the combustion unit 112.

  Moreover, in the said embodiment, the plant growth promotion apparatus 100 set to the operation mode in any one of the 1st-3rd operation mode was mentioned as an example, and was demonstrated. However, the number of operation modes is not limited, and the plant growth promotion device only needs to be set to at least one of the second operation mode and the third operation mode.

  Moreover, in the said embodiment, the structure by which the plant growth promotion apparatus 100 is provided in the greenhouse 10 was mentioned as an example, and was demonstrated. However, the plant growth promotion device 100 may be provided outside the greenhouse 10 as long as the mixed gas can be supplied into the greenhouse 10.

  Moreover, in the said embodiment, it demonstrates as an example when the supply amount control part 154 has one carbon dioxide target value used as the threshold value at the time of adjusting the opening degree of the flow regulating valve 114a in one operation mode. did. However, the target value has a range (a target upper limit value and a target lower limit value are provided), and the concentration of carbon dioxide measured by the second concentration measurement unit 140 is maintained within a range that is greater than or equal to the target lower limit value and less than the target upper limit value. As such, the opening degree of the flow rate adjustment valve 114a may be adjusted. For example, the opening degree of the flow rate adjusting valve 114a may be increased when the concentration of carbon dioxide is less than the target lower limit value, and the opening degree may be decreased when the concentration is higher than the target upper limit value.

  Moreover, in the said embodiment, the case where there is one nitrogen oxide target value used as the threshold value when the air ratio control part 156 adjusts the opening degree of the flow regulating valve 116a in one operation mode is mentioned as an example. explained. However, the target value is given a range (the target upper limit value and the target lower limit value are provided), and the nitrogen oxide concentration measured by the first concentration measurement unit 130 is maintained within the target lower limit value and less than the target upper limit value. As described above, the opening degree of the flow rate adjustment valve 116a may be adjusted. For example, the opening degree of the flow rate adjustment valve 116a may be increased when the concentration of nitrogen oxides is less than the target lower limit value, and the opening degree may be decreased when the concentration is higher than the target upper limit value.

In the first operation mode of the above embodiment, even when the concentration of CO ₂ measured by the second concentration measurement unit 140 is sufficient (when the first carbon dioxide target value is satisfied), the combustion unit The configuration in which the combustion by 112 is not stopped has been described as an example. However, the concentration of CO ₂ in which the second concentration measuring unit 140 is measured is, if they meet the first carbon dioxide target value, may stop the combustion by the combustion unit 112.

Further, in the second and third operation modes of the above embodiment, the CO ₂ concentration measured by the second concentration measurement unit 140 is sufficient (the first carbon dioxide target value or the second carbon dioxide target value is satisfied). And the combustion by the combustion unit 112 is not stopped even when the concentration of NO ₂ measured by the first concentration measurement unit 130 is sufficient (when the first nitrogen oxide target value is satisfied). The configuration has been described as an example. However, the concentration of CO ₂ in which the second concentration measuring unit 140 is measured is, satisfied the first carbon dioxide target value or the second carbon dioxide target value, and the concentration of NO ₂ in which the first concentration measurement unit 130 has measured the first When the 1 nitrogen oxide target value is satisfied, combustion by the combustion unit 112 may be stopped.

Moreover, in the said embodiment, the supply amount control part 154 controls the supply amount of fuel so that the concentration of CO _{2 in} the atmosphere of the greenhouse 10 is maintained at a predetermined carbon dioxide target value. I gave it as an explanation. However, the supply amount control unit may not maintain the CO ₂ concentration in the atmosphere of the greenhouse 10 at the predetermined carbon dioxide target value as long as the supply amount of the fuel can be controlled.

  In addition, each process of the plant cultivation method of this specification does not necessarily need to process in time series along the order described as a flowchart, and may include the process by parallel or a subroutine.

  The present invention can be used for a plant growth promoting device that promotes plant growth.

DESCRIPTION OF SYMBOLS 100 Plant growth promotion apparatus 112 Combustion part 120 Supply means 154 Supply amount control part 156 Air ratio control part

Claims (3)

A plant growth promoting device for promoting plant growth,
A combustion section that burns fuel to generate a mixed gas containing carbon dioxide and nitrogen oxides;
A supply amount control unit for controlling a supply amount of fuel to the combustion unit;
An air ratio control unit that controls the air ratio of the combustion unit so that the concentration of nitrogen oxides in the atmosphere of the cultivation area is maintained at a predetermined nitrogen oxide target value ;
Supply means for supplying the mixed gas generated by the combustion section to a plant cultivation area;
Equipped with a,
The air ratio control unit maintains the nitrogen oxide concentration in the atmosphere of the cultivated land at the first nitrogen oxide target value until a predetermined period has elapsed after sowing, and after the predetermined period has elapsed, A plant growth promotion device, characterized in that the second nitrogen oxide target value is maintained below the first nitrogen oxide target value . The supply amount control section, the concentration of carbon dioxide in the atmosphere of the cultivation area is to be maintained at a predetermined carbon dioxide target value, to claim 1, characterized in that to control the supply amount of the fuel The plant growth promotion apparatus as described. In accordance with an operation input by an operator, an operation mode selection unit that selects one operation mode from a plurality of operation modes is provided.
The plurality of operation modes include at least
An operation mode in which the carbon dioxide target value is set to a first carbon dioxide target value, and the nitrogen oxide target value is set to a first nitrogen oxide target value;
An operation mode in which the carbon dioxide target value is set to a second carbon dioxide target value less than the first carbon dioxide target value, and the nitrogen oxide target value is set to the first nitrogen oxide target value;
The plant growth promotion device according to claim 2 , wherein

Images