JP7168842B1 - How to reduce carbon dioxide - Google Patents

Abstract

A method for reducing carbon dioxide by using exhaust air with a high carbon dioxide concentration from a specific building as a concentration that maximizes photosynthesis. SOLUTION: The concentration of carbon dioxide in the exhaust air discharged from the ventilation equipment of a specific building is about 900 ppm, and the carbon dioxide is released into the atmosphere as it is. On the other hand, a greenhouse for greenhouse cultivation is a closed space, and since carbon dioxide is consumed by photosynthesis of plants, it was necessary to use a carbon dioxide generator. By installing a greenhouse on the roof of a specific building, and directing the exhaust air from the building to the greenhouse as it is, the photosynthesis of plants is maximized, and carbon dioxide is consumed to reduce the carbon dioxide concentration to about 500 to 600 ppm. This is a method of discharging into the atmosphere after As photosynthesis becomes more active, the produced agricultural products have higher yields and higher quality than before, contributing to an increase in profits. Become. [Selection drawing] Fig. 1

Description

The present invention combines exhaust air containing about 900 ppm of carbon dioxide emitted from a specific building that is managed in accordance with the Building Environmental Sanitation Management Standards and that the concentration of carbon dioxide at which plant photosynthesis is maximized is approximately the same. It relates to a method for reducing the amount of carbon dioxide emitted.

Specified buildings are maintained and managed according to the "Environmental Sanitation Management Standards for Buildings" under the "Act on Ensuring Sanitary Environments in Buildings" (abbreviated as "Building Sanitation Law"). One of the air environment standards is defined as "the content of carbon dioxide is 1000 ppm or less", which means that the air in the building will be properly ventilated. However, when considering the energy saving of air conditioning, it is better to have less ventilation, and since ventilation is operated in a range that does not exceed the standard value, many specific buildings emit air with a carbon dioxide concentration of around 900 ppm. will do.

A greenhouse is a closed space in order to maintain the temperature inside even when the outside temperature is low. Therefore, when sunlight is received and the carbon dioxide inside the plant is consumed by photosynthesis, the concentration may be lower than that in the outside air, resulting in carbon dioxide deficiency. Therefore, carbon dioxide fertilization is performed by supplying carbon dioxide into the greenhouse by means of a carbon dioxide generator.

There are two main methods of carbon dioxide fertilization: (1) Supplying fossil fuel as combustion gas (a method of generating carbon dioxide generator) (2) Supplying from liquefied carbon dioxide cylinders. Since (1) supplies carbon dioxide and is combustion gas, the gas temperature is also high, and the temperature inside the greenhouse rises to the extent that it becomes unsuitable for the growth environment of plants. Therefore, carbon dioxide fertilization is limited to a short time in the morning. (2) does not cause a temperature rise due to supply, but has an aspect of being relatively expensive in terms of cost.

There is also CCU (Carbon dioxide capture and utilization), which separates carbon dioxide from the exhaust gas emitted from thermal power plants and uses it for plant growth, but it requires large-scale equipment. It is necessary to cooperate with different departments such as power generation and greenhouse cultivation.

JP 2011-135817 A

In Patent Document 1, a method of reducing carbon dioxide by absorbing carbon dioxide generated in the facility by plants to be sold in the cultivation house is shown. is collected and the collected carbon dioxide is supplied to the cultivation house. A carbon dioxide recovery device is required due to its configuration, but the method for recovering carbon dioxide is not specifically shown. Regardless of the method, there is a problem that the equipment cost for the carbon dioxide recovery device is incurred.

In Non-Patent Document 1, it is a carbon dioxide generator by burning kerosene used in many greenhouse cultivations, and it incorporates a device to lower the temperature of the combustion gas, but when carbon dioxide is consumed in greenhouse cultivation Nonetheless, there is the problem of daring to produce carbon dioxide, which is a greenhouse gas.

A first carbon dioxide reduction method of the present invention is a method for reducing carbon dioxide in the exhaust air emitted from a specific building that is managed in accordance with the Building Environment Sanitation Management Standards, wherein the exhaust air contains Utilizing the fact that the carbon dioxide concentration of about 900 ppm matches the carbon dioxide concentration at which the photosynthesis of the plant is maximized, the exhaust air is led to the greenhouse house and used as it is for greenhouse cultivation, thereby increasing the yield and improving the quality of the harvested product. is characterized by realizing

The carbon dioxide reduction method of the second aspect of the present invention comprises a greenhouse house for cultivating plants installed on the roof of the specific building, an exhaust duct of the specific building, and an air supply duct of the greenhouse. It is a method of reducing carbon dioxide by photosynthesis of plants cultivated in the greenhouse house, in which a gap is provided between the greenhouses and an air-supply fan that is constantly operated is provided at the air supply port to take in the exhaust air. Due to the gap, exhaust air from the specific building is supplied into the greenhouse during the daytime, and when the exhaust air from the specific building is stopped at night, the air is supplied by the air supply fan which is always in operation without any operation. It is characterized in that outside air is supplied to the greenhouse through the gap.

In the carbon dioxide reduction method of the third aspect of the present invention, in the specific building that operates even at night, a switching damper is provided at the air supply port of the greenhouse house so that the air supply point can be switched, so that the exhaust air is reduced at night. The exhaust air is discharged to the atmosphere through the gap, and the exhaust air does not enter the greenhouse house.

According to the present invention of claim 1, it is possible to reduce the carbon dioxide in the exhaust air discharged from the specific building as ventilation, and the carbon dioxide concentration in the exhaust air of the specific building is continuously increased from 900 ppm to about 500 ppm. can be effectively reduced. However, the reduction value of the carbon dioxide concentration changes depending on the size of the greenhouse and the amount of plants cultivated.

The exhaust air supplied to the greenhouse has a temperature of 28 to 32 degrees Celsius in summer and 18 to 20 degrees Celsius in winter, which is effective in preventing abnormal temperature rise in summer and low temperature in winter. In addition, since the exhaust air maintains the above-mentioned temperature, the temperature in the greenhouse house is not raised by carbon dioxide fertilization, so carbon dioxide fertilization, which was limited to a short time until now, is performed continuously during the sunshine hours. It is possible. Therefore, the environment for activating photosynthesis can be maintained for a longer period of time than in the past, and the carbon dioxide generator, which had to be used until now, is no longer necessary, and the fuel and electricity costs that have been spent therefor are also no longer needed.

According to the present invention of claim 2, a gap is provided between the duct of the exhaust port of the specific building and the air supply port of the greenhouse house. When exhaust air from the specific building is stopped at night and the exhaust air is no longer supplied, outside air can be drawn in through the gap and supplied to the greenhouse house. In a specific building that does not operate at night, it is not necessary to provide a switching device between the exhaust air and the outside air just by providing the gap.

According to the present invention of claim 3, in the specific building that operates at night, a switching damper is provided at the air supply port of the greenhouse house, and at night, the exhaust air is released to the atmosphere from the gap through the switching operation by the switching operation, and the switching damper It is possible to take outside air into the air supply port of the greenhouse house and maintain an appropriate environment for plants to breathe at night.

Other effects are as follows. Contribute to improving the image of an excellent company that cares about the environment, have a refreshing effect as biophilia for building users by having greenery, and many specific buildings are located in urban areas and are close to agricultural consumption areas. Therefore, if the agricultural products produced in the greenhouse can be consumed within the building or sold in the neighborhood, the transportation energy will be almost zero, resulting in the ultimate "local production for local consumption".

It is a system outline figure of the whole present invention. FIG. 4 is an explanatory diagram of the operation of the switching damper;

The target buildings shall be specified buildings under the Building Sanitation Act. This is based on the premise that the concentration of carbon dioxide in the exhaust air is about 900 ppm because the building is managed based on the "Environmental Sanitation Control Standards for Buildings" for the reason described above.

[First embodiment]
A case of a building with working hours during the day and no people at night is shown. FIG. 1 is a schematic diagram of the system of the present invention. Exhaust air from a specific building passes through a total heat exchanger 11 and is discharged. Exhaust air is air with a concentration of about 900 ppm due to carbon dioxide discharged as human exhalation, and is clean because it is air from an area where people are active until just before, and is supplied to the greenhouse house 3 as it is. .

Fruit vegetables such as tomatoes and strawberries or other leafy vegetables (plants suitable for sale are selected from plants whose photosynthesis becomes active as the concentration of carbon dioxide increases) are cultivated in the greenhouse house 3 with hydroponics. do. A complete set of equipment such as water supply and fertilizer supply equipment will be installed for this purpose.

In many plants, if the light is constant, photosynthesis is actively carried out in proportion to the concentration of carbon dioxide up to about 1000 ppm, but photosynthesis does not change much even if the concentration is increased beyond that. Therefore, the concentration of carbon dioxide in the exhaust air is almost the same, and it is effective as carbon dioxide fertilization.

Since the ventilation equipment of a building is generally installed on the roof 2, the greenhouse 3 is installed near the ventilation equipment such as the roof in order to shorten the duct for conveying air as much as possible and to reduce the equipment cost. is desirable. The greenhouse house should have appropriate wind resistance so that it will not be destroyed by strong winds.

An air supply fan 4 is provided at the air intake port of the greenhouse house 3 and is normally operated continuously. Exhaust air is discharged from the duct of the exhaust port of the specific building led to the vicinity of the suction port of the air supply fan 4, is sucked by the air supply fan 4 with the gap 7 therebetween, and is supplied to the greenhouse house 3. Here, the size and shape of the exhaust port duct and the size and shape of the suction port of the air supply fan 4 are matched, and the alignment of the ducts is aligned by facing each other. Most of the exhaust air is guided to the greenhouse house 3 by setting the air volume of the discharged exhaust air and the air volume of the air supply fan 4 to be equal. Even if the amount of exhaust air changes and the air amount of the air supply fan 4 differs, the gap 7 allows the air to flow in and out of the outside air, thus serving as a buffer. Also, when the exhaust fan of the building stops at night, it becomes an outside air intake for sucking outside air from the gap 7 . Therefore, it is desirable that the open area formed by the duct circumference of the exhaust port duct and the gap 7 be equal to the cross-sectional area of the exhaust port duct. For example, if the exhaust port duct is a square with one side of 1 m, the circumference of the duct is 4 m, so the gap 7 is about 0.25 m. It is appropriate to provide a wire mesh in the gap 7 so as not to suck in insects, dust, and the like.

The exhaust air taken into the greenhouse house 3 by the air supply fan 4 is uniformly dispersed by providing a duct inside the greenhouse house 3 so as to contact the plants 9 in the greenhouse as evenly as possible. A discharge louver 8 as an air outlet of the greenhouse house 3 is provided on the opposite side of the air supply fan 4. - 特許庁When measuring the concentration of carbon dioxide in order to grasp the reduction amount of carbon dioxide, the concentration after passing through the air supply fan 4 and the concentration after passing through the discharge louver 8 are measured.

Air in the building is cooled and heated by an air conditioner 10 and exhausted through a total heat exchanger 11 . The inside of the building is maintained at 25-28°C in the summer and 20-22°C in the winter, so the exhaust air is heat-exchanged with the outside air by a total heat exchanger, resulting in a temperature of 28-32°C in the summer and 18-20°C in the winter. and supplied to the greenhouse house 3, it is possible to avoid abnormally high temperatures in summer and low temperatures in winter. When a carbon dioxide generator is used in a conventional greenhouse, the internal temperature of the greenhouse becomes too high, so outside air has to be introduced, and the greenhouse becomes open and maintains a high carbon dioxide concentration. I couldn't. By continuously supplying exhaust air with a high carbon dioxide concentration without increasing the temperature inside the greenhouse, it is possible to maintain a carbon dioxide concentration equal to or higher than that of the outside air for a long period of time.

The building exhaust is operated according to normal working hours (9:00 to 17:00 during the day). Since this time is almost the same as the sunshine time, it is possible to supply exhaust air with a high carbon dioxide concentration during the time period when plants are photosynthesizing, so that photosynthesis is appropriately promoted.

An environment with a high concentration of carbon dioxide is not suitable for plants to breathe at night. Even when the sunshine hours are shortened in winter and the sun sets during the working hours, the switching damper 5 is switched to release exhaust air with a high concentration of carbon dioxide into the atmosphere from sunset to the end of the working hours, and the outside air is released into the greenhouse. By supplying to the house 3, the plant growth environment can be properly maintained. However, the switching damper 5 can be omitted in the case of the first embodiment because the time from sunset to the end of the working time is short.

[Second embodiment]
A building that operates 24 hours a day and a building that operates until late at night are shown. In this case, the high concentration of carbon dioxide in the exhaust air at night will continue. to the greenhouse.

FIG. 2 shows the operation of the switching damper 5. FIG. The partition plate 6 of the damper 5 is positioned at the part a during the daytime sunshine and sucks the exhaust air, and after sunset, the partition plate 6 is switched to the position b to block the exhaust air and introduce outside air. As a result, exhaust air is released to the atmosphere, and outside air is introduced into the greenhouse house 3 . At dawn, the partition plate 6 is returned to the position a so that exhaust air can be introduced. It is appropriate that this operation is automatically switched according to sunrise and sunset.

[Other embodiments]
The switching method of the switching damper 5 has been explained in the switching operation of the partition plate 6, but as another method, opening and closing dampers are provided at each of the exhaust air and outside air intakes, and when one is open, the other is closed. It is possible to switch the air to be inhaled in the same way. Any method for switching the introduced air may be used.

In the above description of the embodiment, the greenhouse house 3 is installed on the roof. The greenhouse 3 may be installed anywhere in the site as long as there is a place other than the rooftop where it can be installed appropriately.

The air environment in specified buildings is maintained in accordance with the Building Environment Sanitation Management Standards, and although it can be said that the concentration of carbon dioxide in the exhaust air emitted from most specified buildings is about the same, even buildings that are not specified buildings However, the present invention can be utilized in any place as long as it is a structure where people gather and exhaust air is generated from there, and even if the carbon dioxide concentration is less than about 900 ppm, the outside air If exhaust air with a higher carbon dioxide concentration can be supplied, an increase in the yield of agricultural products and a reduction in carbon dioxide can be expected.

Even if it is impossible to install the greenhouse house 3 on the roof or the like, if there is a greenhouse house of a greenhouse farmer adjacent to the specific building, and the exhaust air can be supplied to the greenhouse house, the specific building can be supplied with carbon dioxide. It can be used in the same way by giving it a function as a station.

1 Specific Building 2 Rooftop 3 Greenhouse House 4 Air Supply Fan 5 Switching Damper 6 Partition Plate 7 Certain Gap 8 Exhaust Gutter 9 Plant in Greenhouse 10 Air Conditioning in Building 11 Total Heat Exchanger

It can be applied to specific buildings in cities where many office buildings are lined up, and it is possible to obtain the merits of increasing the yield and improving the quality of vegetables in the facilities, as well as reduce the carbon dioxide that has been emitted into the atmosphere.

As an example of the reduction of the amount of carbon dioxide according to the present invention, the amount of reduction of carbon dioxide for one year in an office building with a floor area of 3,000 m ² , which is the smallest scale of a specific building, is estimated.
<Setting conditions>
・Floor area: 3,000 m ² office building ・Required ventilation for offices (general): 7.2 m ³ /m ² h (according to air conditioning and sanitary engineering standards)
・ Weight of carbon dioxide at 20°C: 1.8 kg/m ³
・Ventilation time per day: 8 hours ・Carbon dioxide concentration in exhaust air: 900ppm
・ Carbon dioxide concentration after passing through the greenhouse (assumed): 600 ppm
・Number of days the building is in operation per year: 220 days/year <Estimated figures>
・Ventilation volume per day 7.2 m ³ /m ²・h × 3,000 m ² × 8 h/day = 172,800 m ³ /day ・Reduction of exhaust carbon dioxide in ventilation volume per day 1.8 kg/m ³ x 172,800 m ³ /day x (900-600)/1,000,000 = 93.3 kg/day ・Amount of carbon dioxide reduction for one year 93.3 kg/day x 220 days/year = 20,526 kg/year It is possible to reduce about 20 tons of carbon dioxide in one year in one specific building, which is the smallest in scale, and the fuel and electricity costs that were conventionally used when operating the carbon dioxide generator in greenhouse cultivation. is also unnecessary.

According to the Nara Prefectural Agricultural Experiment Station's "Current Status and Issues of CO ₂ Application in Facility Cultivation", as an example of strawberries cultivated with carbon dioxide fertilization at a concentration of 750 ppm all day, the yield is 70% compared to the case where carbon dioxide fertilization is not applied. It is reported that quality improvement such as increase in color and luster and increase in sugar content is reported. Since carbon dioxide fertilization is effective for long periods of time under sunshine, as in the present invention, the carbon dioxide fertilization time is long and the carbon dioxide concentration is supplied at a high concentration of about 900 ppm, resulting in a further increase in yield and quality. expected to improve. At the same time, the operation of conventional carbon dioxide generators is not required.

Especially when it is carried out in commercial facilities (for example, supermarkets), the greenhouse and the sales place are the same place, so it is possible to sell at the sales floor immediately after harvesting. It can be differentiated as the ultimate local production for local consumption, which is greatly different from the thing that was done.

Vegetables cultivated by effectively utilizing carbon dioxide from human exhalation can be differentiated as a new brand with novelty and can be sold with added value. It is also possible to contribute to sales promotion by having people observe the state of cultivation.

Claims (3)

A method for reducing carbon dioxide in the exhaust air emitted from a specific building that is managed in accordance with the Building Environment Sanitation Management Standards, wherein the carbon dioxide concentration of about 900 ppm contained in the exhaust air and the photosynthesis of plants Utilizing the fact that the maximum carbon dioxide concentration is the same, the exhaust air is led to the greenhouse house and used as it is for greenhouse cultivation, thereby increasing the yield and improving the quality of the harvested product. how to. A gap is provided between the duct of the exhaust port of the specific building and the duct of the air supply port of the greenhouse, and an air supply fan that operates constantly is provided to the air supply port to take in the exhaust air. It is a method of reducing carbon dioxide through photosynthesis of plants cultivated in the greenhouse, wherein the exhaust air from the specific building is supplied into the greenhouse during the daytime due to the presence of a gap, and the exhaust air from the specific building is supplied to the greenhouse during the night. 2. The method for reducing carbon dioxide according to claim 1, wherein outside air is supplied to said greenhouse house through said gap by means of an air supply fan which is always operated without any operation when exhaust is stopped. . In the specific building that operates even at night, a switching damper is provided at the air supply port of the greenhouse house so that the air supply point can be switched. 3. A method according to claim 2, characterized in that no exhaust air enters and instead outside air is allowed to enter the air supply of said greenhouse from a switching damper.

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