JP2753568B2 - Culture device for photosynthetic organisms - Google Patents

Description

The present invention relates to an apparatus for culturing photosynthetic organisms such as photosynthetic bacteria, algae, and plant cells. In particular, such photosynthetic organisms are illuminated by sunlight or artificial light. The present invention relates to an apparatus for culturing photosynthetic organisms, which can uniformly and efficiently irradiate light into the culture tank when irradiating the culture in the culture tank.

[Prior Art] Production of useful substances by culturing photosynthetic organisms has been performed for a long time. Moreover, the photosynthetic reaction requires carbon dioxide gas, that is, carbon dioxide (CO2), and is therefore effective for fixing carbon dioxide, which is considered to be one of the causes of global warming.

As a large-scale culture method of photosynthetic organisms, a method of culturing outdoors in the open pool system under sunlight irradiation is already known. In this case, sunlight cannot reach the water depth because it can reach only water depth of less than 10 cm. As a result, a large site area is required to increase the light irradiation rate. Furthermore, this method has a serious drawback that it is difficult to purely culture photosynthetic organisms because contamination of bacteria from the outside cannot be avoided.

Therefore, a means for culturing the photosynthetic organism by irradiating light to the culture tank containing the photosynthetic organism and the culture solution is employed.

As a culture tank for culturing such photosynthetic organisms, a method of irradiating light from outside the culture tank wall made of a transparent material such as glass has been known for a long time. In this method, the light has the highest light intensity near the outer wall in the culture tank, and decreases as it goes toward the center of the culture tank.
An extremely non-uniform light intensity distribution results. Moreover, when the concentration of organisms increases during the cultivation process of photosynthetic organisms, light can only reach within a few cm from the outer wall due to absorption and scattering of incident light. Thus, light cannot be supplied efficiently.

Therefore, by agitating and mixing the culture solution in the culture tank with a stirrer or a pump, the living organism is circulated and moved to a portion where light can be transmitted, thereby improving the uneven irradiation of light. The method is adopted.

However, especially for organisms such as plant cells, such methods cannot be used because the organisms are susceptible to physical damage due to shearing forces caused by stirring and mixing.

Further, when a material such as glass is used for the outer wall as disclosed in Japanese Patent Application Laid-Open No. 50-157581, it is extremely difficult to increase the size of the culture tank in terms of structural strength.

In order to improve the light irradiation rate, for example, a long circular tube made of a transparent material (glass or the like) having a diameter of several cm or less, as disclosed in JP-A-51-110089, is arranged in a parallel or spiral shape. There is known a culture apparatus for irradiating light after molding. In this device, a large light receiving area is required to effectively irradiate light. In particular, when the actual volume of the culture tank is increased, a considerably long circular tube and a large light receiving area are required. Furthermore, it is difficult to make a large-scale apparatus for large-scale culture due to problems in the strength and structure of the tube material.

Further, for example, JP-A-50-142778, JP-A-57-1021
No. 81, JP-A-61-139382, etc., in order to promote the introduction of light into the inside, immerse the luminous tube in the culture tank, or connect the light guided from the optical fiber to the light emitting device in the culture tank It is also known to directly irradiate light internally. In the case of such an apparatus, although the light can be directly irradiated into the culture tank, the light intensity is high near the arc tube or the luminous device, but the light intensity is low at a position away from the arc tube or the luminous device. Distribution occurs. In order to improve this light intensity distribution, it is conceivable to increase the number of arc tubes or light emitters.However, the ratio of the arc tubes or light emitters to the content of the culture tank increases, resulting in photosynthesis. There is a problem that the actual volume for culturing an organism becomes extremely small.

Further, for example, as disclosed in Japanese Patent Application Laid-Open No. 58-98081, there is a method in which a large number of arc tubes and light emitters are densely arranged in a culture tank in order to make the light intensity uniform. There is a problem that the ratio of the luminous tube or luminous device in the content liquid is increased, and as a result, the actual volume for culturing the photosynthetic organism becomes extremely small. Furthermore, when an arc tube or luminous device is installed in a liquid inside a culture tank, a serious drawback occurs in that photosynthetic organisms adhere to the surface of the luminous tube or luminous device as they grow, and light irradiation is blocked. There is.

In addition, as disclosed in Japanese Patent Application Laid-Open No. 53-20481, as a method of uniformly scattering light inside a culture tank, a light guide made of a transparent material is floated and dispersed in the culture tank, and a part of the inside of the culture tank is dispersed. The introduced light is transmitted, scattered, reflected,
There is also a method in which the light is transmitted throughout the culture tank while repeating refraction. However, in this method, another problem is that the actual culture volume is reduced by the amount by which the light guide is suspended in the tank, and it is necessary to separate the culture medium from the light guide, particularly after culturing. There is also.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-described problems, and provides light necessary for culturing a photosynthetic organism in a culture tank according to the type of the photosynthetic organism. It enables uniform and efficient supply, cultivates photosynthetic organisms under optimal light conditions, and enables large-scale cultivation, enabling the production of useful substances at low cost by photosynthesis, and the efficient production of carbon dioxide. It is an object of the present invention to provide a culture apparatus for photosynthetic organisms capable of realizing immobilization.

[Means for Solving the Problems] That is, the present invention relates to a photosynthetic organism culturing apparatus for culturing the photosynthetic organism by supplying light and carbon dioxide gas into a culture tank containing the photosynthetic organism and a culture solution, A photosynthetic organism culturing apparatus, characterized in that a movable light emitter on a flat plate is provided in a culture tank.

The movable luminous body may be made of a transparent material, and light may be transmitted to the movable luminous body from outside the culture tank.

The movable illuminant can be of any type, and for example, a mechanism for rotating the illuminant in a culture tank or reciprocating the illuminant can be used.

[Action] In the photosynthetic organism culturing apparatus according to the present invention, light irradiation is performed while moving a flat transparent movable illuminant that irradiates light transmitted from the outside into the culture tank inside the culture tank. Therefore, the light source approaches the photosynthetic organism in the culture solution. Therefore, by moving the movable luminous body within a predetermined period, light can be uniformly and efficiently supplied to the photosynthetic organisms in the culture tank, and the photosynthetic organisms can be cultured under optimal light conditions.

In addition, since this movable method does not stir and mix the culture solution for the primary purpose as in the prior art, the amount of light irradiation per unit time or culture according to the type of photosynthetic organism, or By appropriately setting the moving speed of the movable luminous body according to the contents of the liquid, it is possible to irradiate and supply light to the entire inside of the culture tank while preventing damage to living organisms. Of course, since the movable luminous body moves in the culture tank to stir and mix the culture solution,
There is also a secondary effect of uniformly distributing the culture solution or the photosynthetic organism in the culture tank.

Thus, even if a culture tank having a predetermined capacity is used, sufficient and uniform light can be supplied to the inside thereof, and efficient and low-cost culture by large-scale culture is possible.

Next, a photosynthetic organism culturing apparatus 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG.

FIG. 1 is a partial cross-sectional side view showing the entire photosynthetic organism culturing apparatus 1, and FIG. 2 is a sectional view taken along the line II-II of FIG. That is, the culture tank 2, the light collector 3, the wavelength selector 4, and the heat ray remover 5
A light control device 6, a light transmission cable 7, a stirring motor 8, a transmission light connector 9, a light transmission shaft 10, and a movable light emitter 11.

The light collector 3 is for collecting one or both of the sunlight SL and the artificial light source AL at appropriate time intervals, and is constituted by a reflection mirror or the like.

The wavelength selector 4 removes, if necessary, harmful light rays such as ultraviolet rays from the light taken in by the light collector 3 according to the kind of the photosynthetic organism, and emits light having a wavelength optimal for photosynthesis, for example, wavelength. It can supply light of 400 to 700 nm.

The heat ray remover 5 is provided to prevent a temperature rise in the culture tank 2 caused by introducing light into the culture tank 2 as much as possible.
This removes heat rays such as infrared rays in advance. However, the culture tank 2 can be used in combination with a configuration in which the culture tank 2 is accommodated in the water of the thermostatic bath 12 or the like (the phantom line in FIG. 1), or the heat ray remover 5 may be omitted.

The light amount control device 6 controls the amount of light to be supplied and the irradiation time or irradiation timing (continuous or intermittent irradiation, etc.) in accordance with the culture solution 13 containing photosynthetic organisms contained in the culture tank 2. The feedback control is performed by a detection signal from the light amount sensor 14 installed in the camera.

The optical transmission cable 7 is for transmitting and supplying a predetermined amount of light to the culture solution 13 in the culture tank 2 and is made of an optical fiber, a mirror conduit, or another material capable of optical transmission.

The optical path for supplying the light L from the optical transmission cable 7 into the culture tank 2 includes three paths, that is, a first optical path 7A for transmitting to the movable luminous body 11 via the transmission optical connector 9 and the optical transmission shaft 10. By providing the second optical path 7B for transmitting the side of the culture tank 2 and the third optical path 7C for transmitting the bottom of the culture tank 2, light can be more efficiently transmitted into the culture tank 2. The light L transmitted from the upper part of the culture tank 2 is connected and transmitted to the optical transmission shaft 10 in the transmission optical connector 9,
When the stirring motor 8 rotates the movable light-emitting body 11, the center of the culture tank 2 also rotates.

As shown in FIG. 2, the movable light emitting body 11 has a flat plate shape and is made of a transparent material such as quartz, glass, or acrylic. The movable luminous body 11 is made of a material that can withstand steam sterilization and sterilization operation. By sterilizing the inside of the culture tank 2, it is possible to aseptically purify the photosynthetic organism aseptically.

In addition, for example, by forming a predetermined number of long windows 11A in the movable luminous body 11 as shown by virtual lines in FIG. 1, the stirring efficiency can be improved.

The rotation speed of the photosynthetic organism culture device 1 is
According to the main purpose of supplying the light L by the movable luminous body 11, not the purpose of stirring, the photosynthetic organisms in the culture solution 13 can be made within a range that does not damage the photosynthetic organism.

A baffle plate 15 is provided on the inner wall of the culture tank 2 so as to protrude from the movable luminous body 11 (see also FIG. 2). By the relative relationship between the baffle plate 15 and the movable luminous body 11, the culture solution 13 can be stirred as uniformly as possible, and the light L can be uniformly supplied into the culture solution 13. Further, if the baffle plate 15 is made of a transparent material, and the light L is supplied to the baffle plate 15 from the optical transmission cable 7, more sufficient light L can be supplied.

A gas sparger 16 is disposed at the bottom of the culture tank 2. The gas sparger 16 has a gas inlet pipe 17 and a sterilizing filter.
Carbon dioxide gas C can be supplied via 18 and the inlet valve 19. That is, carbon dioxide C is supplied to the culture solution 13 in the culture tank 2 from the supply hole 20 of the gas sparger 16. The generated gas in the culture tank 2 is supplied to the sterilization filter 21 and the outlet valve.
This is discharged from the gas outlet tube 23 via 22.

The carbon dioxide C supplied from the gas inlet pipe 17 is a factory,
Exhaust gas from a steel mill, thermal power plant, or the like can be used, but any gas supply source that requires carbon dioxide C fixation can be connected to the gas inlet pipe 17. This is done if pre-processing is required. If the product of the photosynthetic organism by the culture solution 13 is for culture, pure carbon dioxide C may be supplied.

In the photosynthetic organism culturing apparatus 1 having such a configuration, the light L that is taken in via the light collector 3 and pre-processed by the wavelength selector 4, the heat ray remover 5, and the light quantity control device 6 is transmitted to the transmission optical connector 9 and the optical transmission. The light is transmitted to the movable luminous body 11 through the shaft 10 and the baffle plate 15 is transmitted through the optical transmission cable 7.
And transmission to the gas sparger 16 parts. At the same time, the carbon dioxide C is supplied from the gas inlet pipe 17 to the culture solution 13 in the culture tank 2.
To supply. Thus, in the presence of the light L and the carbon dioxide gas C, photosynthesis is performed by the photosynthetic organisms in the culture solution 13, and the carbon dioxide gas C is immobilized.

Since the movable luminous body 11 rotates at a predetermined cycle, the light source moves toward the photosynthetic organism in the culture solution 13, and the light L supplied into the culture tank 2 becomes a floating photosynthesis. It will be supplied uniformly to the living organisms, and there will be no part in the culture tank 2 where the supply of light L is insufficient. In other words, when the movable light-emitting body 11 is stationary, even if there is a part having a low light intensity in a part located at a position remote from the movable light-emitting body 11, it moves due to the rotation of the movable light-emitting body 11. As a result, the light intensity also increases at the position. The continuous movement of the movable luminous body 11 eliminates the uneven distribution of the relative light intensity.

Thus, in the culture device 1, the movable luminous body 11
Moves, the light L can be uniformly irradiated into the culture tank 2 and the culture solution 13 and the photosynthetic organisms can be stirred and mixed, so that all the photosynthetic organisms in the culture solution 13 are always uniform and uniform. Light L can be received, and the culture can be performed in a stable light environment.

In addition, compared to the conventional immobile illuminant method, the stirring and mixing powers are extremely small, which saves energy and prevents the photosynthetic organism from being damaged by excessive shearing force. It is also suitable for culturing photosynthetic organisms that are extremely weak.

Furthermore, since the movable luminous body 11 itself performs a rotational movement,
There is also an additional effect that the surface is always washed by the liquid flow generated by the movement king, and the photosynthetic organisms do not adhere to the surface and reduce the light irradiation efficiency unlike the immobile luminous body, always high intensity Light can be stably emitted for a long period of time.

In the culture device 1 of the present invention, the type of photosynthetic organism to be cultured, the concentration of the organism at the time of culture,
If the shape, size, etc. of the movable light emitting body 11 are arbitrarily set,
The scale of the culture layer 2 can be increased to a desired volume, and an efficient structure such as space saving can be realized.

The light irradiation efficiency can be further improved by appropriately selecting the number of the transmission cables 7 or the connection position to the culture tank 2.

In the present invention, the movable system of the movable light-emitting body 11 is arbitrary, and is not limited to the rotating system, but may be a reciprocating system in the vertical direction or the horizontal direction, a rotating direction reversing system, or the like. In short, the movable luminous body 11 is movable so that the light L can be uniformly supplied to the photosynthetic organism in the culture solution 13 inside the culture tank 2.

[Effects of the Invention] As described above, according to the present invention, a photosynthetic organism is cultured,
Also, in fixing the carbon dioxide gas, a flat transparent movable luminous body was moved in the culture tank as a method of supplying light, and a baffle plate was provided opposite to the movable luminous body, so that the conventional Higher density and higher density can be supplied to the culture medium at a much higher concentration and at a higher speed compared to the culture equipment, and without causing any damage to living organisms. A bioreactor for efficient mass production of useful substances by culturing and a bioreactor for efficient carbon dioxide fixation can be realized.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view showing the entire photosynthetic organism culturing apparatus 1 according to one embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II of FIG. DESCRIPTION OF SYMBOLS 1 ... Culture apparatus of photosynthetic organisms 2 ... Culture tank (reactor main body) 3 ... Condenser 4 ... Wavelength selector 5 ... Heat ray remover 6 ... Light amount control device 7 ... Optical transmission cable 7A ... … The first optical path 7B …… the second optical path 7C …… the third optical path 8 …… the stirring motor 9 …… the transmission optical connector 10 …… the optical transmission axis 11 …… the movable luminous body 11A …… the long window 12 …… Chamber 13 …… Culture containing photosynthetic organisms 14 …… Light sensor 15 …… Baffle plate 16 …… Gas sparger 17 …… Gas inlet tube 18 …… Bactericidal filter 19 …… Inlet valve 20 …… Supply Hole 21: Bactericidal filter 22: Outlet valve 23: Gas outlet tube C: Carbon dioxide SL: Sunlight AL: Artificial light source L: Supply light

Claims (3)

(57) [Claims] 1. A photosynthetic organism culturing apparatus for cultivating a photosynthetic organism by supplying light and carbon dioxide gas into a culture tank containing the photosynthetic organism and a culture solution, the apparatus being provided at a central portion of the culture tank. A movable luminous body composed of a flat transparent material, and a baffle plate provided around the movable luminous body and protruding from the inner wall of the culture tank; and An apparatus for culturing photosynthetic organisms, which transmits light from outside the culture tank. 2. An apparatus for culturing photosynthetic organisms according to claim 1, wherein said movable luminous body is rotated in said culture tank. 3. An apparatus for culturing photosynthetic organisms according to claim 1, wherein said movable luminous body is reciprocated in said culture tank.