JP2008228622A - Trigeneration system of greenhouse for protected horticulture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a carbon dioxide feeding device and system of a greenhouse for protected horticulture, easily removing impurities contained in exhaust gas, efficiently using CO<SB>2</SB>for application, and capable of greatly saving energy to be considerate to the environment. <P>SOLUTION: This trigeneration system of a greenhouse for protected horticulture includes supplying electric power, heat and carbon dioxide to a greenhouse for protected horticulture. The trigeneration system has a motor 11 which supplies fuel containing carbon to produce electric power, a waste heat collecting vessel 13 which is connected to the motor 11 and collects waste heat of the motor 11, and a carbon dioxide storing vessel 12 which is arranged between the motor 11 and the waste heat collecting vessel 13, and uses a carbon dioxide absorbing material mainly containing lithium complex oxide. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of a trigeneration system for a greenhouse for horticulture that supplies electric power, heat, and carbon dioxide to the greenhouse for horticulture.

As is well known, in greenhouses for horticultural horticulture, warmers are used for indoor heating when the temperature is low at night. This warmer uses fuel oil, kerosene, LP gas, and city gas as fuel, and burns it with a burner as a heat source. On the other hand, in order to produce high-quality horticultural crops, CO ₂ application devices that increase the concentration of carbon dioxide (hereinafter referred to as CO ₂ ), which is one of the raw materials for photosynthesis in a greenhouse, are also widespread. The exhaust gas of the warmer contains CO ₂ at a higher concentration than in the atmosphere in order to burn fuel that is a hydrocarbon, and a device for supplying this exhaust gas directly into the greenhouse as CO ₂ application has been put into practical use. ing. As examples of disclosing these techniques, for example, Patent Document 1 and Patent Document 2 are known.

In addition, as shown in FIG. 10, a cogeneration system that uses a gas engine or the like as a prime mover is introduced to use the generated power as a power source for artificial lighting or agricultural facilities. Systems that are collected and used to warm greenhouses are also popular in Europe. In addition, a so-called heat / electricity / carbon dioxide trigeneration system was introduced for the purpose of supplying CO ₂ contained in the exhaust gas of the prime mover from this cogeneration system into the greenhouse for use in photosynthesis. Yes.

In FIG. 10, reference numeral 1 in the figure is a prime mover, and a radiator 2 is disposed in the vicinity thereof. A denitrator 3, a catalyzer 4, and an exhaust heat recovery device 5 are sequentially connected to the prime mover 1. In the system of FIG. 10, the exhaust heat of the prime mover 1 is recovered by the exhaust heat recovery device 5 and used as a heating source for heating the greenhouse 6, and the surplus is stored in the hot water storage tank 7.
JP 2004-344154 A JP 2004-169937 A

In greenhouse horticulture, most of the electricity generated is limited to artificial lighting and other uses. Therefore, when the generator is operated during a period of sufficient sunshine other than the winter season, surplus power is sold through the grid. However, since the selling price of electricity is not high, it is not very good in terms of operation to operate a generator to supply heating or CO ₂ . By the way, among the electricity, heat, and CO ₂ supplied to the greenhouse, the highest priority is to secure a heat source that maintains the temperature of the greenhouse, and the generator based on the heat supply will be operated. . However, the time zones where electricity and heat are required often do not match, and conventional trigeneration systems have a hot water storage tank to temporarily store heat and warm the greenhouse even when the generator is not operating. As a heat source, a system used as a heat source has been put into practical use.

However, the necessary time zone of CO ₂ is mainly several hours from early morning of sunrise to ventilation in the greenhouse. Therefore, even if the prime mover, which is a CO ₂ source, is operated during this time period, electricity and heat are often unnecessary, and efficient operation is difficult. In addition, nitrogen oxides, sulfur oxides, and unburned hydrocarbons contained in gas engine exhaust gas are factors that hinder crop growth, so a denitrifier and a catalytic device are required as an exhaust gas cleanup system. Has led to an increase in size and cost.

The present invention has been made in consideration of such circumstances, and is an environmentally-friendly greenhouse for horticultural use that can easily remove impurities contained in exhaust gas, efficiently use CO ₂ for application, and can greatly save energy. The purpose is to provide a trigeneration system.

  The present invention (first invention) is a trigeneration system for a greenhouse for horticulture that supplies electric power, heat, and carbon dioxide to a greenhouse for horticulture, and a prime mover that generates power by supplying a fuel containing carbon. A connected exhaust heat recovery device for recovering the exhaust heat of the prime mover, and a carbon dioxide storage device using a carbon dioxide absorbent mainly including a lithium composite oxide disposed between the prime mover and the exhaust heat recovery device A trigeneration system characterized by comprising:

  In addition, the present invention (second invention) is a trigeneration system that supplies electric power, heat, and carbon dioxide to a greenhouse for horticulture, and is connected to the prime mover that supplies fuel containing carbon to generate electricity. A greenhouse for horticultural horticulture, comprising a carbon dioxide reservoir using a carbon dioxide absorber mainly containing lithium composite oxide and a heat accumulator for storing the heat of combustion exhaust gas from the prime mover during power generation This is a trigeneration system.

According to the present invention, it is possible to obtain an environment-friendly greenhouse horticulture trigeneration system that can easily remove impurities contained in exhaust gas and efficiently use CO ₂ for application, and further save energy. .

The facility horticultural greenhouse trigeneration system according to the present invention will be described below.
1st invention WHEREIN: Furthermore, it has further the gas switching means which can select whether the carbon dioxide in a carbon dioxide storage device is introduce | transduced into a greenhouse at the exit side of the said carbon dioxide storage device, , Supply electricity and heat to the greenhouse while accumulating carbon dioxide in the carbon dioxide reservoir, and select two operating states to supply only the carbon dioxide accumulated in the carbon dioxide reservoir to the greenhouse while the prime mover is stopped It is preferable to have a configuration having a possible operation mode. Thus, during operation of the prime mover, electricity and heat are supplied to the greenhouse while accumulating carbon dioxide in the carbon dioxide reservoir as shown in FIG. 3 described later. On the other hand, while the prime mover is stopped, only the carbon dioxide accumulated in the carbon dioxide reservoir is supplied to the greenhouse as shown in FIG. As described above, according to the first invention, by adopting the above-described configuration, it is possible to supply CO ₂ to the greenhouse when necessary regardless of the operating state of the prime mover, and a clean configuration with a simple configuration. CO ₂ rich air can be supplied to the greenhouse.

  2nd invention WHEREIN: While equipped with the gas switching means which can select whether the carbon dioxide in a carbon dioxide reservoir is introduce | transduced into a greenhouse at the exit side of the said carbon dioxide reservoir, On the exit side of the said thermal storage device And heat supply switching means capable of selecting whether the heat accumulated in the heat accumulator is introduced into the carbon dioxide reservoir or the greenhouse, while carbon dioxide is accumulated in the carbon dioxide reservoir during operation of the prime mover. When electricity and heat are supplied to the greenhouse and the motor is stopped, only the carbon dioxide accumulated in the carbon dioxide reservoir is supplied to the greenhouse, or only the heat accumulated in the regenerator is supplied to the greenhouse, or It is preferable to have a configuration having an operation mode capable of selecting four operation states for supplying both carbon dioxide from the carbon reservoir and heat from the regenerator. As a result, during operation of the prime mover, electricity and heat are supplied to the greenhouse while accumulating carbon dioxide in the carbon dioxide reservoir as shown in FIG. 5 described later. Further, while the prime mover is stopped, only the carbon dioxide accumulated in the carbon dioxide reservoir is supplied to the greenhouse (see FIG. 7 described later), or only the heat accumulated in the regenerator is supplied to the greenhouse (FIG. 8 described later). Or carbon dioxide from the carbon dioxide reservoir and heat from the heat accumulator are supplied (see FIG. 9 described later).

According to the second invention, by adopting the above-described configuration, it is possible to supply CO ₂ and heat to the greenhouse simultaneously or separately when necessary regardless of the operating state of the prime mover. In addition, CO ₂ and heat can be supplied to the greenhouse in accordance with the optimum time zones, respectively, and an apparatus with a high degree of freedom in operation can be constructed. Further, by supplying a portion of the heating source CO ₂ reservoir from the heat accumulator during CO ₂ supply, it is possible to greatly reduce the power consumption associated with the CO ₂ supply.

Next, embodiments of the present invention will be described with reference to the drawings. The present embodiment is not limited to the one described below.
(Example 1) (Corresponding to Claims 1 and 2)
FIG. 1 shows a configuration of a facility horticulture greenhouse trigeneration system according to the present invention, and FIG. 2 shows an example of a daily operation time schedule. In FIG. 2, (A) is an example showing when power, heat and carbon dioxide are required, and (B) is an example showing when power, heat and carbon dioxide are supplied.

Reference numeral 11 in FIG. 1 indicates a prime mover. The prime mover 11 drives a generator, and the greenhouse 16 uses the generated electricity for artificial lighting. A CO ₂ reservoir 12 and an exhaust heat recovery device 13 are sequentially connected to the prime mover 11. Moreover, the outlet side of the CO ₂ reservoir 12, i.e. CO ₂ line connecting the reservoir 12 and the exhaust heat recovery unit 13, and a line branching from the line to the greenhouse 16, the electric damper 17a as respective gas switching means, 17b is provided. The electric dampers 17a and 17b can select whether or not to introduce the carbon dioxide (CO ₂ ) accumulated in the CO ₂ reservoir 12 into the greenhouse 16. That is, when the electric damper 17a is closed and the electric damper 17b is opened, carbon dioxide from the CO ₂ reservoir 12 is introduced into the greenhouse 16, and when both the electric dampers 17a and 17b are closed, the CO ₂ reservoir 12 is supplied. It will accumulate carbon dioxide. The prime mover 11, the CO ₂ storage device 12, the exhaust heat recovery device 13, the electric dampers 17a and 17b, and the like constitute a greenhouse system greenhouse trigeneration system.

The exhaust heat of the prime mover 11 is collected in the CO ₂ reservoir 12 and used as a heating source for heating the greenhouse 16, and the surplus is stored in the hot water storage tank 14. When the prime mover 11 is a reciprocating engine, the cooling water for cooling the engine block circulates, so the heat radiated by the radiator 15 disposed near the prime mover 11 together with the exhaust heat recovery device 13 is radiated. It may be recovered. The exhaust gas containing CO ₂ exiting the prime mover 11 passes through the CO ₂ reservoir 12 filled with the carbon dioxide absorbent before passing through the exhaust heat recovery device 13, where CO ₂ is accumulated. A carbon dioxide absorbent (hereinafter also synonymous with a CO ₂ absorbent) is mainly composed of a lithium composite oxide, and absorbs CO ₂ in the reaction represented by the following formula (1) in a temperature range from room temperature to 600 ° C.
Li ₄ SiO ₄ + CO ₂ ⇔Li ₂ SiO ₃ + Li ₂ CO ₂ + Q (1)
This reaction is a reversible reaction, and when heated to about 650 ° C., CO ₂ is released by the reverse reaction, and the absorbent material can be reused. Along with the reaction, the right side is exothermic and the left side is endothermic. FIG. 1 shows a configuration in which CO ₂ can be supplied regardless of the operating state of the prime mover 11 using this feature.

The operation state of the trigeneration system will be described with reference to FIGS. FIG. 3 shows a state where the prime mover 11 is operating and supplying electricity and heat while accumulating CO ₂ . In the example of FIG. 2A, this state is from 15:00 to around 21:00. After that, during the night until the next morning, the prime mover 11 repeats intermittent operation in accordance with the heat demand, and surplus power is sold through the grid while accumulating CO ₂ . In the example of FIG. 2B, this state is from 21:00 to around 7:00 the next morning.

While the prime mover 11 is in operation, the CO ₂ reservoir 12 directly absorbs and accumulates CO ₂ contained in the exhaust gas at an exhaust gas temperature of 200 ° C. to 400 ° C. by the reaction of the above formula (1). At this time, the exhaust heat recovery device 13 may be located either upstream or downstream of the CO ₂ reservoir 12. However, since the exothermic reaction occurs as described above during CO ₂ absorption, the exhaust gas is heated and becomes higher than the exhaust temperature of the prime mover 11. Therefore, if the exhaust heat recovery device 13 is installed downstream of the CO ₂ storage device 12 as shown in FIG. 3, the heat generated by the absorption reaction can be recovered efficiently. In this case, the outlet gas of the CO ₂ reservoir 12 is discharged to the outside through a flue or the like. In the CO ₂ reservoir 12, in addition to CO ₂ , trace amounts of oxides that are harmful to crops, such as NOx and SOx, or that inhibit growth may be absorbed depending on the partial pressure, but most of them react. I will slip through.

On the other hand, the prime mover 11 in FIG. 4 illustrating the supply has stopped, the CO ₂ accumulated from CO ₂ reservoir 12 in a greenhouse. In the example of FIG. 2A, this state is from 7 o'clock to 12 o'clock. When supplying CO ₂ , the CO ₂ absorbent filled in the CO ₂ reservoir 12 is efficiently heated to a predetermined temperature with an electric heater or the like to release CO ₂ , diluted with air, and rich in CO ₂ . Send air into the greenhouse. The outlet gas of the CO ₂ reservoir 12 is switched from flue emission to greenhouse introduction using the electric dampers 17a and 17b described above. At this time, only 100% pure CO ₂ is released from the CO ₂ absorbent, and no other harmful substances are supplied to the greenhouse. Further, the prime mover 11 and the exhaust heat recovery unit 13 may be in any state regardless of whether they are stopped or operating, and CO ₂ can be supplied completely independently.

In summary, in the facility horticultural greenhouse trigeneration system according to the first embodiment, CO ₂ can be supplied to the greenhouse 16 when necessary regardless of the operating state of the prime mover 11. Further, the CO ₂ reservoir 12 plays the role without using desulfurization / denitration and reduction / oxidation catalyst, and clean CO ₂ rich air can be supplied to the greenhouse 16 with a simple configuration.

(Example 2) (Corresponding to Claims 3 and 4)
FIG. 5 shows a trigeneration system for a greenhouse for horticulture according to the second embodiment. However, the same members as those in FIG. The system includes a prime mover 11, a CO ₂ reservoir 12, a heat accumulator 21, electric dampers 17a and 17b, and electric dampers 22a and 22b as heat supply switching means provided on the outlet side of the heat accumulator 21. Is done. One of the electric dampers 17a and 17b is provided on a line connecting the CO ₂ reservoir 12 and the heat accumulator 21, and a line branched from this line and connected to the greenhouse 16. The other electric dampers 22a and 22b are provided on lines connecting the heat accumulator 21, the CO ₂ reservoir 12, and the greenhouse 16 respectively. FIG. 6 shows an example of the daily driving time schedule. When the prime mover 11 is in operation, the generated electricity is supplied to artificial lighting in the greenhouse. In the example of FIG. 6, this state is from 16:00 to 1 o'clock the next day.

The exhaust gas emitted from the prime mover 11 passes through the CO ₂ reservoir 12 and the heat accumulator 21 and accumulates CO ₂ and exhaust heat, respectively. While the prime mover 11 is in operation, the CO ₂ reservoir 12 directly absorbs and accumulates CO ₂ contained in the exhaust gas at an exhaust gas temperature of 200 ° C. to 400 ° C. by the reaction of the above formula (1). At this time, the heat accumulator 21 may be located either upstream or downstream of the CO ₂ reservoir 12. However, since the exothermic reaction occurs during CO ₂ absorption as described above, the exhaust gas is heated and becomes higher than the prime mover discharge temperature. Therefore, if the heat accumulator 21 is installed downstream of the CO ₂ reservoir 12 as shown in FIG. 5, the heat generated by the absorption reaction can be efficiently recovered. The heat accumulator 21 is heat resistant and has a large heat capacity, such as a ceramic filler. It is desirable that heat insulation be strictly insulated so as to minimize heat dissipation and maintain as high a temperature as possible. In this case, the outlet gas of the heat accumulator 21 is discharged to the outside through a flue or the like.

When supplying CO _2, with the electric damper 22a opened and the electric damper 22b closed, air was passed through the heat accumulator 21 as shown in FIG. 7, and the CO ₂ reservoir 12 was heated to 200 ° C. to 300 ° C. Bring in air. In the example of FIG. 6, this state is from 7 o'clock to 12 o'clock. In order to supply CO ₂ from the CO ₂ reservoir 12, a temperature of 650 ° C. to 700 ° C. is required by the reaction of the above formula (1), and therefore, from 200 ° C. to 300 ° C. to a reaction temperature of 650 ° C. to 700 ° C. Is heated electrically. However, by using the sensible heat of the air sent from the heat accumulator 21 as an auxiliary, the temperature inside the CO ₂ reservoir 12 can be quickly raised and the power consumption associated with the CO ₂ supply can be greatly reduced.

On the other hand, when only the heat supply is required in the greenhouse 16, with the electric damper 22a closed and the electric damper 22b opened, the greenhouse is heated through a heat medium such as air or hot water as shown in FIG. What is necessary is just to warm, and heat supply is possible irrespective of the driving | running state of the motor | power_engine 11. In the example of FIG. 6, this state is from 1 o'clock to about 7 o'clock. Further, when both heat and CO ₂ are required, as shown in FIG. 9, the heat is stored in the greenhouse 17 through a heat medium such as air or hot water, while the CO ₂ reservoir 12 is supplied with an electric heater or the like. CO ₂ is supplied by heating to a reaction temperature of 650 ° C. to 700 ° C. by the electric means and then applying heat necessary for the endothermic reaction. At this time, the electric dampers 17a and 22a are closed, and the electric dampers 17b and 22b are in an open state. In the example of FIG. 6, this state is from 7 o'clock to 9 o'clock. In this case, the electric energy required for the CO ₂ supply is increased as compared with the operation method shown in FIG. 7, but the heat and the CO ₂ supply can be performed completely independently. A means for switching and supplying the heat of the heat accumulator 17 to the CO ₂ reservoir 12 and the greenhouse can be easily realized by, for example, an electric damper.

In summary, according to the facility horticultural greenhouse trigeneration system according to the second embodiment, CO ₂ and heat can be supplied to the greenhouse 16 when necessary regardless of the operating state of the prime mover 11. Moreover, CO ₂ reservoir 12 and the heat storage unit 21 and the electric damper 17a, 17b, 22a, by having a 22b, can be fed separately of CO ₂ and heat. For this reason, it is possible to supply CO ₂ and heat to the greenhouse 16 in accordance with optimum time zones, respectively, and it is possible to construct an apparatus with a high degree of freedom of operation. Further, by supplying a portion of the heating source 11 of CO ₂ reservoir 12 from the heat accumulator 21 when CO ₂ supply, it is possible to greatly reduce the power consumption associated with the CO ₂ supply.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Specifically, in the first and second embodiments, the case where a hot water storage tank is provided is described, but this is not always necessary. Furthermore, you may combine suitably the component covering different embodiment.

The figure which shows the structure of the trigeneration system of the greenhouse for greenhouses which concerns on Example 1 of this invention. The figure which shows an example of the operation time schedule of the carbon dioxide supply apparatus of FIG. The figure which shows the driving | running state when the motor | power_engine of the carbon dioxide supply apparatus of FIG. 1 is operating. The figure which shows the driving | running state when the motor | power_engine of the carbon dioxide supply apparatus of FIG. 1 has stopped. The figure which shows the structure of the trigeneration system of the greenhouse for greenhouses which concerns on Example 2 of this invention. The figure which shows an example of the operation time schedule of the carbon dioxide supply apparatus of FIG. It shows the operating state when supplying CO ₂ to the greenhouse at the carbon dioxide supply apparatus of FIG. The figure which shows the driving | running state when only heat supply is required in a greenhouse in the carbon dioxide supply apparatus of FIG. Shows the operating state in the case both heat and CO ₂ in the greenhouse is required in the carbon dioxide supply apparatus of FIG. The figure which shows the structure of the coordination system of the conventional greenhouse for greenhouses.

Explanation of symbols

11 ... engine, 12 ... CO ₂ reservoir, 13 ... exhaust heat recovery device, 14 ... hot water tank, 16 ... greenhouses, 17a, 17b, 22a, 22b ... electric damper 21 ... heat accumulator.

Claims (4)

In the horticulture greenhouse trigeneration system that supplies power, heat, and carbon dioxide to the greenhouse for horticulture,
A prime mover that supplies fuel containing carbon to generate electric power, an exhaust heat recovery device that is connected to the prime mover to recover exhaust heat of the prime mover, and that is disposed between the prime mover and the exhaust heat recovery device. A trigeneration system comprising a carbon dioxide reservoir using a carbon dioxide absorbent containing a composite oxide. Further comprising gas switching means on the outlet side of the carbon dioxide reservoir capable of selecting whether or not to introduce carbon dioxide in the carbon dioxide reservoir into the greenhouse;
During operation of the prime mover, supplying electricity and heat to the greenhouse while accumulating carbon dioxide in the carbon dioxide reservoir,
The facility horticulture according to claim 1, wherein the horticultural horticulture has an operation mode in which only two operation states can be selected to supply only the carbon dioxide accumulated in the carbon dioxide reservoir to the greenhouse while the prime mover is stopped. Greenhouse trigeneration system. In the trigeneration system that supplies electricity, heat, and carbon dioxide to greenhouses for horticulture,
A prime mover that generates power by supplying fuel containing carbon, a carbon dioxide reservoir that uses a carbon dioxide absorbent mainly containing lithium composite oxide, and heat of combustion exhaust gas from the prime mover during power generation. A greenhouse for horticultural horticulture, characterized by comprising a heat accumulator for storing water. On the outlet side of the carbon dioxide reservoir, provided with gas switching means that can select whether or not to introduce carbon dioxide in the carbon dioxide reservoir into the greenhouse, and accumulated in the regenerator on the outlet side of the heat accumulator A heat supply switching means capable of selecting whether heat is introduced into the carbon dioxide reservoir or the greenhouse,
During operation of the prime mover, supplying electricity and heat to the greenhouse while accumulating carbon dioxide in the carbon dioxide reservoir,
While the prime mover is stopped, only the carbon dioxide accumulated in the carbon dioxide reservoir is supplied to the greenhouse, only the heat accumulated in the regenerator is supplied to the greenhouse, or the carbon dioxide and the heat accumulation from the carbon dioxide reservoir Supply both heat from the vessel,
4. The greenhouse system for horticulture for facilities and horticulture according to claim 3, wherein the system has an operation mode in which four operation states can be selected.

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