JPH0787955A - Method for immobilizing co2 by photosynthesis and device therefor - Google Patents

Abstract

PURPOSE:To improve CO2 immobilization rate by directly immobilizing CO2 in vapor phase by making use of photosynthetic bacteria. CONSTITUTION:A carrier is exposedly provided in a vapor phase and photosynthetic bacteria 5 are attached to the surface of the carrier. The bacteria 5 bear liquid film 20 on the surface. When an exhaust gas containing CO2 comes into contact with the bacteria 5, the CO2 is immobilized by the bacteria 5 with concomitant production of a gas as a result of the CO2 immobilization.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a thermal power plant, a boiler,
The present invention relates to a CO ₂ immobilization method by photosynthesis and an apparatus therefor capable of efficiently immobilizing CO ₂ contained in exhaust gas from a water treatment plant or the like using photosynthetic organisms.

[0002]

_2. Description of the Related Art A conventional method for fixing CO ₂ by photosynthesis and its apparatus are shown in FIGS. 14 and 15. In FIG. 14, an exhaust gas 1 containing CO ₂ from a thermal power plant or the like is supplied into a liquid culture bioreactor 2 in which a photosynthetic organism 5 floats in a culture liquid 4. The culture fluid 4 is irradiated with light 6 such as sunlight or artificial light to generate the processing gas 3.

CO ₂ in the exhaust gas 1 is dissolved in water in the culture solution 4 in the liquid culture bioreactor 2 to become HCO ₃ as shown in the equations (1) and (2). Next, as in formula (3), the photosynthetic organism 5 such as microalgae or photosynthetic bacteria generates CO ₂ from HCO ₃ . Next, the photosynthetic organism 5 uses this CO ₂ as a substrate for photosynthesis and immobilizes it using the light energy of light. That is, microalgae use CO ₂ as shown in formula (4) and C ₆ using light energy.
Converted to organic compounds such as H ₁₂ O ₆ (glucose) and O ₂ (oxygen), photosynthetic bacteria use CO ₂ as shown in formula (5) and C ₆ H ₁₂ O ₆ (glucose) using light energy. It is converted to the organic compound and S (sulfur). In this way, photosynthetic organisms immobilize CO ₂ as an organic compound, and C
The processing gas 3 generated by fixing O ₂ is released into the atmosphere.

[0004]

[Equation 1] FIG. 15 shows a conventional CO ₂ fixing device by photosynthesis.
In FIG. 15, the exhaust gas 1 is supplied into the liquid culture bioreactor 2 via the gas pipe 7, and the CO ₂ in the exhaust gas 1 is microalga or photosynthetic bacteria inoculated into the culture solution 4 in the liquid culture bioreactor 2. The light energy of the light source 6 is used for immobilization by the photosynthetic organism 5 such as. CO _{2 in} exhaust gas
The processing gas 3 generated by immobilizing the gas is released into the atmosphere through the pipe 8.

During this time, the pump 12 is driven at appropriate times, and the substrate solution, which is the nutrient of the photosynthetic organism 5, is supplied from the substrate solution tank 13 into the liquid culture bioreactor 2 through the pipe 10. Further, the photosynthetic organism 5 propagated by the photosynthetic process is discharged from the tube 10 by opening the opening / closing valve 11.

[0006]

[Problems to be Solved by the Invention] C by conventional photosynthesis
In the method and apparatus for O ₂ immobilization, the photosynthetic organism 5 floats in the culture medium 4, so that the following problems occur. That is, the light is about 10 below the liquid surface of the culture medium 4.
It permeates only up to around cm, and CO ₂ in the exhaust gas 1 cannot be efficiently immobilized.

In this case (1) Liquid culture bioreactor 2
Of the liquid culture bioreactor 2, or (2) increase the tank height of the liquid culture bioreactor 2 to receive light on the side surface, or (3) arrange a plurality of liquid culture bioreactors 2 in series. It is conceivable to perform multi-stage processing.

However, when the installation area of the liquid culture bioreactor 2 of (1) is increased, the exhaust gas 1 supply device becomes complicated and a large number of devices are required. In the case of increasing the tank height of the liquid culture bioreactor 2 of (2), it is necessary to use a light-transmissive material such as glass having high strength on the side surface thereof. Furthermore, when a plurality of liquid culture bioreactors 2 of (3) are arranged in series, CO ₂ in the exhaust gas 1 is repeatedly treated by a plurality of liquid culture bioreactors,
A large power for the blower that can supply the gas to the next-stage bioreactor is required. That is, C by conventional photosynthesis
With the O ₂ immobilization method and apparatus, it is difficult to obtain a high CO ₂ immobilization rate with small power and space saving.

Further, in the conventional CO ₂ immobilization method and apparatus by photosynthesis, when the photosynthetic organism 5 is recovered as biomass, the photosynthetic organism 5 is dispersed in the culture medium 4 so that the culture medium 4 is separated by sedimentation. A concentration step of centrifugation or centrifugation is required. Therefore, the installation area of the device required for the concentration process becomes large, and the power required for those processes is applied.

The present invention has been made in consideration of the above points, and it is possible to save space by increasing the CO ₂ immobilization rate and to efficiently recover the immobilized photosynthetic organisms as biomass. CO by photosynthesis
₍₂₎ It is intended to provide an immobilization method and an apparatus therefor.

[0011]

The invention according to claim 1 is
A step of adhering a photosynthetic organism having a liquid film on the surface or inside of a fixed object in a gas phase, and contacting the photosynthetic organism with an exhaust gas containing CO ₂ and irradiating the photosynthetic organism with light. A method of immobilizing CO ₂ by photosynthesis, which comprises the step of immobilizing CO ₂ by a photosynthetic organism to generate a processing gas.

According to a fourth aspect of the present invention, a fixed object provided in a gas phase, a photosynthetic organism having a liquid film on the surface or inside of the fixed object, and exhaust gas containing CO ₂ are provided. A CO ₂ immobilization device by photosynthesis, comprising: a gas supply unit that supplies gas to the photosynthetic organism side.

According to a fifth aspect of the present invention, there is provided a solid culture bioreactor in which a carrier is arranged in a gas phase inside, and a photosynthetic organism having a liquid film on the surface is attached to the surface or the inside of the carrier. A gas supply means for supplying an exhaust gas containing CO ₂ into the solid culture bioreactor, a gas discharge means for discharging a processing gas in the solid culture bioreactor, and a substrate solution for photosynthetic organisms in the solid culture bioreactor And a substrate solution supplying means for intermittently supplying the CO ₂ immobilization device by photosynthesis.

The invention according to claim 6 has a porous outer wall having a carrier attached to the outer surface thereof, and a solid culture bioreactor in which a photosynthetic organism having a liquid film on the surface is attached to the surface or the inside of the carrier. A gas supply means for supplying an exhaust gas containing CO ₂ into the solid culture bioreactor, a gas discharge means for discharging a processing gas in the solid culture bioreactor, and a substrate for a photosynthetic organism in the solid culture bioreactor. A CO ₂ immobilization device by photosynthesis, comprising: a substrate solution supply means for intermittently supplying a solution.

The invention according to claim 7 has a solid culture bioreactor having a porous outer wall, and a photosynthetic organism having a liquid film on the surface adhered to the surface or inside of the outer wall, and the solid culture bioreactor. CO by photosynthesis, comprising: a gas supply means for supplying an exhaust gas containing CO ₂ therein; and a substrate solution supply means for intermittently supplying a substrate solution of a photosynthetic organism into the solid culture bioreactor. ₂ Immobilization device.

[0016]

According to the first aspect of the present invention, the photosynthetic organism attached to the surface or the inside of the fixed object is contacted with the exhaust gas containing CO ₂ , and the photosynthetic organism is irradiated with light. ₂ is fixed and a processing gas is generated.

According to the fourth aspect of the present invention, the gas containing means supplies CO ₂ -containing gas to the photosynthetic organism attached to the surface or the inside of the solid object to bring it into contact with the photosynthetic organism. CO ₂ is immobilized to generate a processing gas.

According to the fifth aspect of the invention, when the exhaust gas containing CO ₂ is supplied into the solid culture bioreactor by the gas supply means, it is attached to the surface or inside of the carrier arranged in the solid culture bioreactor. In photosynthetic organisms, CO ₂ is immobilized by light energy and a processing gas is generated. The processing gas is released by the gas release means, and the substrate solution is intermittently supplied to the photosynthetic organism by the substrate solution supply means.

According to the invention of claim 6, when the exhaust gas containing CO ₂ is supplied into the solid culture bioreactor by the gas supply means, the CO _{2 in} the exhaust gas passes through the porous outer wall to the surface or the inside of the carrier. CO ₂ is immobilized on the photosynthetic organism by the light energy in contact with the photosynthetic organism attached to the photosynthetic organism, and the processing gas in the solid culture bioreactor is released by the gas releasing means. The substrate liquid is intermittently supplied to the photosynthetic organism by the substrate liquid supply means.

According to the invention described in claim 7, when the exhaust gas containing CO ₂ is supplied into the solid culture bioreactor by the gas supply means, the CO _{2 in} the exhaust gas passes through the porous outer wall to the surface or the inside of the carrier. Contact with photosynthetic organisms attached to. CO ₂ is immobilized on the photosynthetic organism by the light energy, and the process gas in the solid culture bioreactor is released by the gas releasing means. The substrate liquid is intermittently supplied to the photosynthetic organism by the substrate liquid supply means.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are views showing a first embodiment of the present invention.

In FIG. 1, a carrier 21, which is a fixed object, is provided in the gas phase, and a photosynthetic organism 5 having a liquid film 20 on the surface is attached to the surface of the carrier 21. in this case,
The liquid film 20 and the carrier 21 are combined. The fixed object is not limited to the carrier 21 and may be the outer wall of the reactor.

Exhaust gas 1 supplied from a thermal power plant or the like is
It passes through the liquid film 20 and comes into contact with the photosynthetic organism 5. In this case, CO ₂ contained in the exhaust gas 1 is converted into HCO by the reaction of the above-described formulas (1) and (2) while passing through the liquid film 20.
₃ ^- to become. This HCO ₃ ⁻ is then converted into CO ₂ by the photosynthetic organism 5 according to formula (3). During this time, the photosynthetic organism 5 is irradiated with light 6, and the light energy of the light 6 converts CO ₂ into an organic compound (C ₆ H ₁₂ O ₆ ) based on Formula (4) and Formula (5), and thereafter. This organic compound is immobilized on the photosynthetic organism 5. CO in exhaust gas 1
_The processing gas 3 generated by fixing ₂ is discharged to the outside.

The carrier 21 may have a large number of linear holes 21a as shown in FIGS.

In the case of FIG. 2, the photosynthetic organism 5 adheres to the surface of the carrier 21, and the exhaust gas 1 contacts the photosynthetic organism 5 through the hole 21a.

In the case of FIG. 3, the photosynthetic organism 5 adheres to the inside of the carrier 21, and the exhaust gas 1 contacts the photosynthetic organism 5. Process gas 3 produced by fixing CO _{2 in} exhaust gas 1
Are released to the outside through the holes 21a.

In the conventional liquid phase, CO ₂ dissolved in the liquid phase is used.
According to the present embodiment, CO ₂ in the gas phase can be directly immobilized by the photosynthetic organism 5, whereas only the photosynthetic organism 5 is immobilized. Further, since the photosynthetic organism 5 is exposed in the gas phase, the liquid phase does not hinder the transmission of light, and the CO ₂ immobilization rate can be improved.

Next, a second embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 4, the CO ₂ immobilization device is provided with a solid culture bioreactor 22 having an outer wall 30, and in the gas phase in the solid culture bioreactor 22, 8 units supported by a support rod 25 are provided. A letter-shaped carrier 21 is arranged. Further, the photosynthetic organism 5 having the liquid film 20 (FIG. 1) on the surface is attached to the surface of the carrier 21.

A gas pipe 23 for supplying exhaust gas and a gas pipe 24 for releasing processing gas are connected to the solid culture bioreactor 22, and the substrate liquid is connected to the gas pipe 23 via a pipe 29 having an opening / closing valve 27. The tank 26 is connected.

Next, the operation of the CO ₂ fixing device shown in FIG. 4 will be described.

First, the liquid culture bioreactor 2 (see FIG. 15)
The carrier 21 is put into the inside of the carrier 21 and the chlorella which is the photosynthetic organism 5 is attached and fixed on the surface of the carrier 21 or inside the carrier 21. Next, the carrier 21 to which the photosynthetic organism 5 is adhered and fixed is arranged in the solid culture bioreactor 22, and then the exhaust gas 1 of the thermal power plant is supplied into the solid culture bioreactor 22 through the gas pipe 23.

CO ₂ contained in the exhaust gas 1 is stored in the carrier 21.
It directly contacts the photosynthetic organism 5 that is attached and fixed to, and is fixed as an organic compound by the light energy of sunlight of light 6. The processing gas 3 from which CO ₂ contained in the exhaust gas 1 has been removed is released into the atmosphere via the gas pipe 24. During this period, the substrate solution containing the substrate and water which are the nutrients of the photosynthetic organism 5,
At any time, for example, once a day, open the on-off valve 27 to open the substrate liquid tank 2
6 through the pipe 29 into the solid culture bioreactor 22. When the photosynthetic organism 5 excessively proliferates and enlarges, the carrier 21 to which the photosynthetic organism 5 adheres is timely, for example, 1
After the supply of the exhaust gas 1 is stopped once a week, the support rod 25 is taken out from the solid culture bioreactor 22 to the outside. Next, washing with water is performed, and the overgrown photosynthetic organism 5 is forcibly exfoliated from the carrier 21d, and the exfoliated photosynthetic organism 5 is recovered as a useful substance. The carrier 21 on which the photosynthetic organism 5 has been washed is returned together with the support rod 25 into the solid culture bioreactor 22.

According to this embodiment, the carrier 21 is a support rod 25.
Since it is in the shape of a figure 8 string supported by, the photosynthetic organism 5 can be attached and fixed in the gap between the string-shaped carriers 21, and the concentration of the photosynthetic organism 5 can be increased. Further, since the substrate liquid can be supplied from the substrate liquid tank 26 only by opening and closing the opening / closing valve 27, the power is small and the maintenance is easy. Further, since the photosynthetic organism 5 attached and fixed to the carrier 21 is washed outside the solid culture bioreactor 22, less power is required and the degree of washing can be adjusted.

Next, a third embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 5, the CO ₂ immobilization device comprises a solid culture bioreactor 22 having an outer wall 30, and porous covers 32a and 32b are detachably attached to the upper part and the inside of the solid culture bioreactor 22. It is installed in. Further, the inside of the solid culture bioreactor is divided into upper and lower parts by the inner porous cover 32b, and the 8-shaped carrier 21 supported by the support rods 25 is arranged in each of the upper and lower parts. ing.

A transparent flat plate-shaped carrier 31 is provided on the upper porous cover (outer wall) 32a, and the surface or inside of the 8-shaped carrier 21 and the flat plate-shaped carrier 31 has a surface. A photosynthetic organism 5 having a liquid film 20 is attached. Further, the pipe 2 having the opening / closing valve 27 from the substrate liquid tank 26
The substrate solution supplied via 9 is sprayed on the flat carrier 31.

Next, the operation of the CO ₂ fixing device shown in FIG. 5 will be described.

A liquid culture solution of chlorella, which is the photosynthetic organism 5, is immersed in the surfaces of the figure-eight carrier 21 and the flat carrier 31 in advance, and then the carrier 21 and the carrier 31 are arranged at predetermined positions. Next, the exhaust gas 1 is supplied to the lower portion of the solid culture bioreactor 22 via the gas pipe 23. During this time, the upper and lower porous covers 32a and 32b are transparent, and the light 6 passes through the porous covers 32a and 32b and reaches the photosynthetic organism 5 in each chamber. The supplied exhaust gas 1 flows from the lower part to the upper part in the solid culture bioreactor 22, and the CO ₂ in the exhaust gas 1 comes into contact with the photosynthetic organisms 5 arranged in each chamber, and photosynthesis of the photosynthetic organisms 5 causes an organic compound. Is fixed as.

Next, the CO ₂ in the exhaust gas 1 is converted into the flat carrier 31.
It comes into contact with the photosynthetic organism 5 on the flat plate-shaped carrier 31 via, and is immobilized as an organic compound by the photosynthesis of the photosynthetic organism 5. The processing gas 3 from which CO ₂ has been removed is released into the atmosphere via the gas pipe 24.

The substrate solution and water, which serve as nutrients for the photosynthetic organism 5, are opened from the substrate solution tank 26 by opening the on-off valve 27, and the pipe 29b.
Is supplied from above the photosynthetic organism 5. The photosynthetic organism 5 on the surface of the plate-shaped carrier 31 that has grown excessively can be collected by washing with water from above. See also figure-shaped carrier 2
The photosynthetic organism 5 on the surface 1 has porous covers 32a and 32b.
The carrier 21 is removed together with the support rod 25, and the carrier 21 is recovered by washing with water.

According to the present embodiment, the inside of the solid culture bioreactor 22 is divided into upper and lower parts, and the photosynthetic organism 5 is provided in each chamber.
The 8-shaped carrier 21 to which is attached is arranged, and on the upper porous cover 32a of the solid culture bioreactor 2,
Since the flat carrier 31 to which the photosynthetic organism 5 is attached is arranged, the CO ₂ immobilization rate can be improved.

Next, a fourth embodiment of the present invention will be described with reference to FIG. The fourth embodiment shown in FIG. 6 is one in which the photosynthetic organism 5 having the liquid film 20 is directly attached to the surface or the inside of the upper porous cover 32a without providing a flat carrier, and the other is shown in FIG. It is substantially the same as the third embodiment shown in FIG.

In FIG. 6, the exhaust gas 1 supplied from the gas pipe 23 to the lower portion in the solid culture bioreactor 22.
Flows from bottom to top. During this period, CO in the exhaust gas 1
₂ is fixed by the photosynthetic organism 5 attached to the figure-shaped carrier 21 and the photosynthetic organism 5 attached to the porous cover 32a.

Next, a fifth embodiment of the present invention will be described with reference to FIG.
Will be described.

In the fifth embodiment shown in FIG. 7, a liquid culture bioreactor 2 having a photosynthetic organism 5 is connected upstream of a gas pipe 23, and a gas pipe 7 for supplying exhaust gas is connected to the liquid culture bioreactor 2. The connection is the same as that of the second embodiment shown in FIG. Also, the substrate liquid tank 2
A tube 29 from 6 is inserted into the solid culture bioreactor 22.

Next, the operation of the CO ₂ fixing device shown in FIG. 7 will be described. Exhaust gas 1 is supplied via gas pipe 7 into liquid culture bioreactor 2 into which photosynthetic organisms 5 have been previously charged, and high-temperature exhaust gas 1 is cooled and humidified. At the same time, some CO ₂ is immobilized as an organic compound in the liquid culture bioreactor 2 by the photosynthesis of the photosynthetic organism 5. Next, the exhaust gas in the liquid culture bioreactor 2 is
The photosynthetic organisms 5 in the solid culture bioreactor 22 are supplied to the fixed culture bioreactor 22 via the gas pipe 23.
As a result, CO ₂ remaining in the exhaust gas of the liquid culture bioreactor 2 is almost fixed as an organic compound.
The processing gas 3 from which CO ₂ has been removed is released into the atmosphere via the gas pipe 24.

Next, a sixth embodiment of the present invention will be described with reference to FIG.
Will be described.

In the sixth embodiment shown in FIG. 8, a liquid culture bioreactor 2 having a photosynthetic organism 5 is connected upstream of a gas pipe 23, and a gas pipe 7 for supplying exhaust gas is connected to the liquid culture bioreactor 2. They are connected, and the others are almost the same as the third embodiment shown in FIG.

In FIG. 8, the exhaust gas 1 is cooled and humidified in the liquid culture bioreactor 2 and a part of CO ₂ is fixed. After that, the exhaust gas 1 is a solid culture bioreactor 22.
Most of the CO ₂ is fixed at.

Next, another embodiment of the present invention will be described. In each of the above-described embodiments, the example in which the string-shaped carrier 21 of the figure 8 supported by the support rod 25 is used is shown. A circular string carrier 41 may be attached.

As shown in FIG. 10, a brush-shaped carrier 42 supported by the support rod 25 may be used, and as shown in FIG. 11, a chain-shaped string carrier supported by the support rod 25. 43 may be used.

Further, the example in which the solid culture bioreactor 22 having the carrier 21 arranged therein is arranged in the horizontal direction is shown, but the present invention is not limited to this, and it may be arranged in the vertical direction as shown in FIG. Further, it may be arranged with an inclination in the range of 0 to 90 degrees. Inclined solid culture bioreactor 2
By arranging 2, the substrate solution can be easily supplied.

Further, as shown in FIG. 14, the solid culture bioreactor 22 is vertically arranged, a support plate 35 is provided in the solid culture bioreactor 22, and the spherical carrier 21 is put on the support plate 35. May be.

Further, the substrate solution is turned on / off by the opening / closing valve 27.
Although the example of supplying by F is shown, the invention is not limited to this, and it is also possible to supply by using a pump or the like. Further, it is not necessary to manually wash the photosynthetic organism 5 that has excessively grown, and it is possible to wash it automatically. It is also possible to wash the photosynthetic organism 5 inside the solid culture bioreactor 22.

[0056]

As described above, according to the present invention,
Since CO ₂ in the gas phase can be directly immobilized by photosynthetic organisms, CO dissolved in the liquid phase as in the conventional case
_A large amount of CO ₂ can be immobilized as compared with the case where only ₂ is immobilized. Further, since the photosynthetic organisms are exposed in the gas phase, light transmission is not hindered by the liquid phase as in the conventional case. Therefore, the solidification rate of CO ₂ can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing a case where the carrier has holes in the first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram showing a case where the carrier has holes in the first embodiment of the present invention.

FIG. 4 is a schematic configuration diagram showing a second embodiment of the present invention.

FIG. 5 is a schematic configuration diagram showing a third embodiment of the present invention.

FIG. 6 is a schematic configuration diagram showing a fourth embodiment of the present invention.

FIG. 7 is a schematic configuration diagram showing a fifth embodiment of the present invention.

FIG. 8 is a schematic configuration diagram showing a sixth embodiment of the present invention.

FIG. 9 is a schematic view of a carrier showing another embodiment of the present invention.

FIG. 10 is a schematic view of a carrier showing another embodiment of the present invention.

FIG. 11 is a schematic view of a carrier showing another embodiment of the present invention.

FIG. 12 is a schematic view of a solid culture bioreactor showing another embodiment of the present invention.

FIG. 13 is a schematic view of a solid culture bioreactor showing another embodiment of the present invention.

FIG. 14 is a schematic diagram showing a conventional CO ₂ immobilization method by photosynthesis.

FIG. 15 is a schematic configuration diagram showing a conventional CO ₂ fixing device by photosynthesis.

[Explanation of symbols]

 1 Exhaust Gas 2 Liquid Culture Bioreactor 3 Process Gas 5 Photosynthetic Organism 20 Liquid Membrane 21 Carrier 22 Solid Culture Bioreactor 23 Gas Pipe 24 Gas Pipe 31 Carrier 32a, 32b Porous Cover

Claims (8)

[Claims] 1. A step of adhering a photosynthetic organism having a liquid film on the surface or inside of a fixed object in a gas phase, and contacting the photosynthetic organism with an exhaust gas containing CO ₂ to the photosynthetic organism. Irradiates light to produce CO by photosynthetic organisms
_A method of fixing CO ₂ by photosynthesis, which comprises the step of fixing ₂ to generate a processing gas. _{2. The} CO ₂ by photosynthesis according to claim 1, wherein the fixed body has a large number of holes, and the exhaust gas containing CO ₂ flows into the holes of the fixed body and contacts the photosynthetic organisms.
Immobilization method. 3. The method for immobilizing CO ₂ by photosynthesis according to claim 1, wherein the fixed body has a large number of holes, and the processing gas from the photosynthetic organism is released through the holes of the fixed body. . 4. A fixed object provided in a gas phase, a photosynthetic organism provided on the surface or inside of this fixed object and having a liquid film on the surface, and exhaust gas containing CO ₂ is supplied to the photosynthetic organism side. C by photosynthesis, characterized by comprising a gas supply means
O ₂ immobilization device. 5. A solid culture bioreactor in which a carrier is disposed in a gas phase inside and a photosynthetic organism having a liquid film on the surface is attached to the surface or the inside of the carrier, and the solid culture bioreactor. A gas supply means for supplying an exhaust gas containing CO ₂ therein, a gas discharge means for discharging a processing gas in the solid culture bioreactor, and a substrate liquid for photosynthetic organisms intermittently supplied in the solid culture bioreactor A CO ₂ immobilization device by photosynthesis, comprising: a substrate liquid supply means. 6. A solid culture bioreactor having a porous outer wall having a carrier attached to the outer surface thereof, and a photosynthetic organism having a liquid film on the surface attached to the surface or inside of the carrier, and the solid culture bioreactor. A gas supply means for supplying an exhaust gas containing CO ₂ into the reactor, a gas discharge means for discharging a processing gas in the solid culture bioreactor, and a substrate liquid of a photosynthetic organism intermittently supplied into the solid culture bioreactor. And a substrate solution supply means for performing the photosynthetic CO ₂ immobilization device. 7. A solid culture bioreactor having a porous outer wall, and a photosynthetic organism having a liquid film on the surface attached to the surface or inside of the outer wall, and CO ₂ contained in the solid culture bioreactor. A CO ₂ immobilization device by photosynthesis, comprising: a gas supply means for supplying exhaust gas; and a substrate solution supply means for intermittently supplying a substrate solution of a photosynthetic organism into the solid culture bioreactor. 8. The gas supply means has a liquid culture bioreactor, and in this liquid culture bioreactor, a carrier is arranged in a liquid phase inside, and a photosynthetic organism is attached to the surface or the inside of the carrier. The CO ₂ immobilization device by photosynthesis according to any one of claims 5 to 7, characterized in that.