KR101243110B1

KR101243110B1 - photobioreactor

Info

Publication number: KR101243110B1
Application number: KR1020100098993A
Authority: KR
Inventors: 정상화; 안동규; 박종락; 박정우; 김종태
Original assignee: 조선대학교산학협력단
Priority date: 2010-10-11
Filing date: 2010-10-11
Publication date: 2013-03-12
Also published as: WO2012050325A3; KR20120037313A; WO2012050325A2

Abstract

The present invention provides a microalgae culture photobiological incubator and plate-shaped reaction vessels installed at predetermined intervals to allow microalgae to be cultured therein; It is provided on the reaction vessel is provided with a light concentrating unit for condensing sunlight and a light irradiation unit for irradiating the reaction vessel with light collected by the light condensing unit to irradiate light to the reaction vessel.

Description

Photobioreactor

The present invention relates to an optical bioreactor for mass cultivation of microalgae, and more particularly, to an optical bioreactor having improved light irradiation structure using sunlight in the photobioreactor.

Recently, as industrial emission CO is regarded as the main culprit of global warming, research is being actively conducted to utilize microalgae to fix CO₂.

Microalgae can play a role in the treatment of wastewater, immobilization of carbon dioxide, etc., due to their various capabilities, and have been used for the production of useful substances such as fuels, cosmetics, feed, food coloring and pharmaceutical raw materials. In the meantime, useful and high value added substances are constantly being discovered and expanding their applications.

There are many factors such as the composition of the medium, temperature, pH, light intensity, light quantity, etc., which affect the increase in the biomass and useful products of the microalgae, but among them, light occupies the largest share. In general, a device for culturing photosynthetic microalgae for the purpose of immobilizing carbon dioxide can be largely divided into a mass culture (open system) and a photobioreactor (closed system) outdoors. Outdoor mass cultivation apparatus including pond type has been mainly used in the form of reaction facilities such as lakes or large ponds and is commercially available in some countries.

However, this type of cultivation facility has the advantages of low initial investment and easy maintenance, but it is difficult to contaminate, isolate and purify, low cell concentration, high mass (especially nitrogen source), high water quality and quantity demand, and irregular climate. Due to problems such as conditions, expensive labor costs, the installation is extremely limited. In particular, the effective growth of light is not achieved inside the culture apparatus, the growth rate of the cells is low, the growth yield of the cells is low, and a large installation space is required to remove a large amount of carbon dioxide.

In order to solve the problems of such an outdoor mass culture apparatus, a high-concentration culture is carried out through a small-sized reactor to produce an amount equal to or greater than that of the outdoor mass culture apparatus, .

Currently developed forms include general stirred reactors, plate reactors, tubular reactors, column reactors, etc., and in all these types of reactors, efficient transmission of light is the most important point in reactor design. When the concentration of microalgae cells is low, medium and gas injection are the most important factors for cell proliferation, but when the high concentration is reached, the brightness is the most important factor. This is because the higher the concentration, the shorter the light transmission length.

That is, the light applied while the microalgae is incubated becomes more and more bulky as the microalgae grows, so that the microalgae on the surface of the reactor can continue to receive light, but the microalgae inside the reactor are microalgae on the surface. Because of the shadow effect will not be able to receive enough light to grow. However, most of the microalgae photobioreactors designed to date do not overcome this point, and thus the production efficiency thereof is lower than that of other microbial bioreactors. To overcome this and to transmit light efficiently. Recently, photobioreactors using internal light sources have been studied. Widely used photobioreactors include tubular photoreactors and panel photoreactors that use sunlight as an external light source. The reactor has a structure in which the narrow and long rectangular or cylindrical pipes are densely adhered to circulate the culture in order to maximize the irradiation area exposed to sunlight and to shorten the light transmission distance into the culture.

Such photobioreactors have advantages and disadvantages in their respective forms. In particular, the reactor using the fiber as the internal light source has a good light efficiency, but there is a problem that the cells adhere to the surface of the optical fiber. In addition, in the case of using a light source such as a fluorescent lamp as an internal light source, there is a problem in that the device must be operated continuously and accordingly excessive use of electricity (energy) is not efficient.

In order to solve this problem, Korean Patent No. 0933741 discloses a photobioreactor for culturing microalgae. The disclosed reactor uses an LED, a flexible LED, and has a structure in which the light source is directly in contact with the culture solution. In such a structure, micro algae are attached to the surface of the light source, thereby reducing light efficiency.

In addition, Korean Patent Publication No. 10-2009-0055170 discloses a semi-cylindrical photobiological reactor, and Korean Patent Registration No. 10-0897019 discloses an optical bioreactor for culturing microalgae with high efficiency. This reactor has a structure in which sunlight is irradiated to the photobioreactor using a reflective collector and an optical fiber. US Patent Application No. 2009/0211150 discloses a technical configuration for producing biomass and biodiesel by culturing microalgae Gloella in high concentration using a tubular photobioreactor, and US Patent Application No. 2005/0255584 In order to improve the light efficiency, a tubular photobioreactor having a surface area increased while using a partition of a transparent material is disclosed.

U.S. Patent No. 595876 discloses a tubular photobioreactor using a complex parabolic concentrator to improve the light collection efficiency of sunlight.

The present invention is to solve the above problems, to prevent the microalgae attached to the interior of the reaction vessel, and maximize the photovoltaic and LED light source irradiation efficiency of microalgae cultivation optical bioreactor that can increase the productivity of microalgae To provide.

The microalgae cultivation optical bioreactor of the present invention for achieving the above object is a plate-like reaction vessel that is installed at predetermined intervals so that the microalgae can be cultured therein; A light concentrating unit installed on the reaction vessel and condensing sunlight, and a light irradiation unit for irradiating the plate-shaped reaction vessel with light collected by the condensing unit to irradiate light to the reaction vessel. It is characterized by.

In the present invention, the light irradiation unit includes a plate-shaped light guide plate provided to correspond to the reaction vessel, and a reflection plate provided on the rear surface of the light guide plate. It is provided on the edge of the light guide plate and provided with a lamp module for irradiating light on the plate through the light guide plate.

The light irradiation unit includes a light guide plate having first and second light guide parts positioned between the reaction vessels, a reflection plate installed between the first and second light guide parts to reflect light to both sides of the first and second light guide parts, and It is provided on the side of the first and second light guide portion and provided with a lamp module for irradiating light to the plate-shaped reaction vessel through the first and second light guide portion.

The light collecting unit includes a Fresnel lens unit or a focusing lens unit installed on the light irradiation unit in the longitudinal direction of the plate-shaped photoreactor. The light collecting unit may be a light collecting lens unit installed on the light irradiation unit in the longitudinal direction of the plate-shaped photoreactor, and the light collecting lens unit may be a fresnel lens.

In the present invention, there is further provided a solar tracking unit for tracking the light collecting lens unit in the east-west direction and north-south direction along the sun.

The microbial photoreactor for culturing the microalgae according to the present invention maximizes the light source irradiation efficiency by using sunlight and a light emitting diode to increase the productivity of the microalgae, and the microalgae adhere to the surface of the light tank means that the light irradiation efficiency is lowered. It can be prevented fundamentally. The photobioreactor collects light while following the sun, and the collected light can be irradiated onto the plate-shaped reaction vessel through the light guide plate.

1 is a perspective view of a photobioreactor according to the present invention,
2 is a perspective view showing an extracting light collecting unit and light irradiation unit;
3 is a cross-sectional view showing a coupling relationship between a light guide plate and a lamp module;
4 is a perspective view showing another embodiment of a lamp module;
5 is a perspective view showing another embodiment of a light converging unit and a light irradiation unit;
6 and 7 are perspective views showing embodiments of the light collecting unit,
8 is a perspective view showing another embodiment of a light converging unit and a light irradiation unit;
9 is a perspective view illustrating a tracking unit for tracking a light collecting unit;
10 is a perspective view showing another embodiment of a tracking unit for tracking the light collecting unit.

1 to 4 show an optical bioreactor for culturing microorganisms in one embodiment of the present invention.

Referring to the drawings, the microalgae cultivation photobioreactor 10 of the present invention is installed at a predetermined interval on the frame 11, the microalgae and the inlet port 21 through which the culture solution is introduced and the microalgae therein Plate-shaped reaction vessel 20 having a culture medium storage space therein so that the culture can be cultured, the light condensing unit 30 for condensing the sunlight is installed on the frame 11, and the reaction vessel 20 Is provided on at least one side of the light condensing unit 30 and the light irradiated from the light and / and the lamp is irradiated with light using a light emitting diode using a light emitting unit (50).

The carbon dioxide supply unit 70 and the oxygen supply unit 75 are connected to the plate-shaped reaction vessel 20 to supply carbon dioxide into the reaction vessel 20. Although not shown in the drawing, the reaction vessel 20 is connected to a seed culture medium and a seed supply unit for supplying and discharging a culture solution and a microalgae seed, and the reaction vessel is connected to a microalgae reservoir and the microalgae. The reservoir is connected to the microalgal pretreatment tank.

The plate-shaped reaction vessel 20 may be made of tempered glass or acrylic-based material which is substantially excellent in light transmission and mechanical strength, and a culture space (not shown) for culturing microalgae is installed therein. The culture space may be composed of a plurality of chambers, the chambers are interconnected structure. In addition, the plate-shaped reaction vessel 20 may have irregularities in order to increase its surface area, and a predetermined pattern may be formed for focusing and scattering light. On the other hand, the inner surface of the reaction vessel 20 of the flat plate may be a coating film made of titanium oxide (TiO₂), etc. in order to prevent the microalgae adhere to the reaction vessel.

And the light condensing unit 30 for condensing sunlight is tracked by the tracking unit 40 to follow the sun.

The light irradiation unit 50 for irradiating light for culturing the microalgae to the plate-shaped reaction vessel 20 is to focus the light collected by the light collecting unit 30 or the light irradiated from the lamp module to be described later. 1 and 2 are shown.

Referring to the drawings, the light irradiation unit 50 is provided with a light guide plate 51 installed to correspond to the reaction vessel 20, and the reaction vessel of the plate through the light guide plate 51 is installed on the edge of the light guide plate 51 ( 20) is provided with a lamp module 60 for irradiating light. At least one side of the light guide plate 51 is formed with a diffusion pattern 52 for scattering or reflecting the light emitted from the lamp module 60 to the front side. The diffusion pattern 52 may be formed of a reflective pattern formed on the back surface of the light guide plate 51 using ink, or may have a groove (eg, a V-shape having a predetermined pattern on the back surface of the light guide plate 51 by laser beam or mechanical processing). Grooves) may be formed. The groove formation pattern may include a scroll shape, a grid shape, a shape of an overlapping polygon, and horizontal or vertical grooves having different pitches. In addition, a reflecting plate 53 may be installed on the rear surface of the light guide plate 51 to reflect the light irradiated from the lamp module 60 and irradiated to the rear surface of the light guide plate 51. A diffuser plate (not shown) may be attached to make the illuminance of the light irradiated from the site constant. The light guide plate may be made of transparent synthetic resin, glass, quartz, and the like.

In addition, the lamp module 60 installed at the edge of the light guide plate 51 is installed on both side surfaces and the bottom surface of the light guide plate 51, and is provided on the first lamp module 61 and the bottom surface of the light guide plate 51. The two lamp module 62 is provided. The first and second lamp modules 61 and 62 have substantially the same structure, and each of the circuit boards 61a and 62a having the same width as that of the side or bottom surface of the light guide plate 51, and The light emitting diodes 61b and 62b are provided on the circuit boards 61a and 62a at predetermined intervals to irradiate light from the edge of the light guide plate 51.

Here, the inlet groove 54 is formed in the side and the bottom of the light guide plate 51 corresponding to the light emitting diodes 61b and 62b, so that the light emitting diodes 61b and 62b are the inlet grooves. It is preferable to prevent the light from being scattered around the edge of the light guide plate by being inserted into the 54, and the unevenness 54a for scattering the light is preferably formed on the inner surface of the recess 54.

The lamp module for irradiating light to the light guide plate 51 is not limited to the above-described embodiment and may use cold cathode fluorescent lamps (CCFL) as shown in FIG. 4. In this case, a cold cathode fluorescent lamp in close contact with the edge of the light guide plate 51 and a reflective member 64 may be provided to surround the edge of the light guide plate to prevent light emitted from the cold cathode fluorescent lamp from being irradiated to a region other than the light guide plate. .

5 shows another embodiment of the light irradiation unit according to the present invention. The same components as in the above embodiment indicate the same reference numerals.

Referring to the drawings, the light irradiation unit is installed between the plate-shaped reaction vessel 20, the light collected from the light collecting unit 30 or the light irradiated from the lamp module to the reaction vessel 20 located on both sides of the lamp module In order to be irradiated, the light guide plate 56 having first and second light guide parts 56a and 56b positioned between the reaction vessels 20 and 20 is provided. Reflecting plates 57 for reflecting to both sides of the first and second light guides between the first and second light guides 56a and 56b and on the side surfaces of the first and second light guides 56a and 56b. And lamp modules 58 and 59 for irradiating light to the plate-shaped reaction vessels 20 through the first and second light guides 56a and 56b.

A diffusion pattern may be formed on the opposing surfaces of the first and second light guides 56a and 56b as described above, and the first and second sides of the reaction vessels 20 and 20 may correspond to each other. A diffuser plate may be installed to maintain a constant illuminance at each portion of the light guides 56a and 56b. The lamp modules 58 and 59 have a configuration in which the light emitting diodes 58b and 59b are installed on the circuit boards 58a and 59a as in the embodiment.

On the other hand, the light guide plate may be made of a single double-sided light guide plate that can irradiate the light collected by the light collecting unit on both sides.

A diffusion lens unit 51a may be formed on an upper surface of the light guide plate 51 corresponding to the light collecting unit 30 to diverge the focused light into the light guide plate.

The light converging unit 30 focuses the sunlight in the form of a line and is incident on the upper surface side of the light guide plate 51. As shown in FIGS. 1, 6, 7, and 8, a Fresnel lens of a cylindrical type ( It may be made of a cylindrical type fresnel or a TIR-concentrator, but is not limited thereto. A lens having a negative power and a lens having a positive power may be combined to focus the sunlight. Can be.

The light collecting unit 30 is not installed on the upper side of all the light irradiation unit, and as shown in FIG. 8, the light irradiation unit 50 is installed on one side of the reaction vessel, and the light irradiation unit 50 located on the other side. It may not be installed on the upper part of '). In this case, after condensing sunlight through one light collecting unit, one side of the reaction vessel is irradiated through the light irradiation unit 50, and the other side of the reaction vessel 20 receives light from the lamp module of the light irradiation unit 50 '. Can be installed to investigate the

On the other hand, the tracking unit 40 is for tracking the light converging unit in the east-west and north-south direction along the sun, one side (front side, south side) hinge axis on the frame 11, as shown in Figure 1 and 9 The sub-frame 42 coupled to the rotatable by rotatable 41 and the upper side of the frame 11 on the other side (back side, north side direction) corresponding to the hinge shaft 41 is installed on the sub-frame 42. A first actuator 43 is provided to lift and adjust the angle of the subframe 42. The first actuator 43 may be formed of a screw jack or a lead screw driven by a motor. The support frame 44 is rotatably installed in the sub-frame 42 in the north-south direction. The support frame 44 is installed at a position corresponding to the light guide plates of the light irradiation units 50, and the support frame 44 focuses and irradiates sunlight onto the light guide plate 51 of the light irradiation unit 50. Fresnel lens that is a light collecting unit 30 to be installed. In addition, links 45 are installed on each of the rotation shafts 44a of the support frames 44 rotatably installed in the subframe 42, and the links 45 are hinged by the connecting links 46 and the hinge pins. A second actuator 47 is installed at one end of the connection link 46 to move forward and backward to follow a Fresnel lens, which is a light collecting unit installed in the support frame, in the east-west direction along the sun. . The second actuator may be made of a jackscrew having a lead screw which is rotated forward and backward by a motor as described above. The tracking unit is not limited to the above-described embodiment and may be any structure as long as the tracking unit 30 can follow the altitude of the sun. For example, as illustrated in FIG. 10, the sub-frame 42, on which the light collecting unit is installed, is provided with a transfer unit 80 for advancing back and forth in the longitudinal direction of the upper surface of the light guide plate according to the height of the sun. The transfer unit 80 has a guide rail 81 which is installed in the frame in a direction parallel to the longitudinal direction of the upper surface of the light guide plate 51 of the light irradiation unit 50 is installed in the subframe 42 and the guide rail ( 81 is provided with a slider 82 coupled with and sliding along. The frame 11 includes a third actuator 83 for moving the subpres 42 forward and backward with respect to the frame 11. The third actuator may have the same structure as the second actuator. The third actuator may be made of a lead motor.

In the photobioreactor 10 of the present invention configured as described above, from the sunrise time to the sunset time, that is, when the sun is floating, the light irradiated to the light collecting unit 30 installed on the upper side of the reaction vessel 20 is collected. The light is collected by the unit 30 and irradiated to the upper surface of the light guide plate 51 of the light irradiation unit 50. The light irradiated to the light guide plate 51 is irradiated to the reaction vessel 20 by the light guide plate 51. Since the light guide pattern is formed on the light guide plate 51, the light formed on the upper surface of the light guide plate 51 may be diffused and irradiated to the reaction vessel side. In particular, since a reflecting plate is provided on the rear surface of the light guide plate 51, light loss can be reduced by reflecting the light irradiated to the rear surface of the light guide plate toward the front side.

In addition, since the weather is weak during the rainy or rainy season, the light emitting diode of the lamp module 60 installed on the side of the light irradiation unit 50 emits light, and the light irradiated from the light emitting diode passes through the light guide plate 51. (20). Therefore, irrespective of external conditions, light may be continuously irradiated to the reaction vessel 20 so that the microalgae may be cultured using the reaction vessel 20. In more detail, the light is irradiated to the reaction vessel 20 by using a light collecting unit and a light guide plate during the day when the sun is normally, and when there is no sun, it is installed on the light guide plate 51 side of the light irradiation unit 50. The first and second lamp modules 61 and 62 are used to irradiate light to the reaction vessel 20. In the daytime when the sunlight is weak, the light collecting unit 30 and the light guide plate 51 and the light guide plate may be disposed on the side of the light guide plate. Using the installed lamp module 60 can always supply a constant light energy into the plate-shaped reaction vessel 20.

On the other hand, the gas in the process of culturing the microalgae may use air, and when the supply of oxygen or carbon dioxide (CO2) can be supplied to these gases. Carbon dioxide can be supplied by mixing 5-20% with a separate gas (eg air).

In addition, the light collecting unit 30 may adjust or slide the angle according to the altitude of the sun by the tracking means, thereby preventing the focusing position from the light guide plate according to the altitude of the sun.

As described above, the photobioreactor of the present invention is an optical bioreactor for mass production of microalgae using a plate-shaped light source that focuses sunlight and applies a light source capable of emitting strong light. It is possible to control the production of the production and to increase the spatial efficiency. In addition, when it is necessary to replace the light source during the cultivation to adjust the light intensity or maintenance of the light source, it is easy to replace it is advantageous to maintain a sterile state.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10; Photobioreactor
11; frame
30; condensing unit
40; tracking unit
50; light irradiation unit

Claims

A plate-like reaction vessel installed at regular intervals to allow microalgae to be cultured therein; A condensing unit installed on the plate-shaped reaction vessel and condensing sunlight;
And a light irradiation unit for irradiating the plate-shaped reaction vessel with the light collected by the light collecting unit to irradiate light to the plate-shaped reaction vessel,
The light irradiation unit is provided to correspond to the reaction vessel of the plate and comprises a plate-shaped light guide plate in which the light collected by the light collecting unit is incident on the upper side side, and a reflecting plate is provided on the back surface of the light guide plate,
And a lamp module installed at an edge of the light guide plate to irradiate light to the plate-shaped reaction vessel through the light guide plate.

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To allow microalgae to be cultured therein, plate-shaped reaction vessels installed to be spaced apart from each other;
A condensing unit installed on the plate-shaped reaction vessel and condensing sunlight;
And a light irradiation unit for irradiating the plate-shaped reaction vessel with the light collected by the light collecting unit to irradiate the plate-shaped reaction vessel with light.
The light irradiation unit includes a light guide plate having first and second light guide portions positioned between the plate-shaped reaction vessels, and a reflection plate provided between the first and second light guide portions to reflect light to both sides of the first and second light guide portions. And a lamp module installed at a side of the first and second light guide parts to irradiate light to the plate-shaped reaction vessel through the first and second light guide parts.
The upper surface of the light guide plate is a microalgae culturing optical bioreactor, characterized in that the diffusion lens portion for diffusing the focused light into the light guide plate is formed.

The method of claim 1 or 4.
Light reflecting grooves of a predetermined pattern is formed on the rear surface of the light guide plate.

The method according to claim 1 or 4,
The condensing unit is a microalgae culturing optical microbial culture, characterized in that provided with a Fresnel lens unit or a focusing lens unit installed on top of the light irradiation unit in the longitudinal direction of the plate-shaped photoreactor.

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5. The method of claim 4,
And a tracking unit for tracking the light collecting unit in the east-west direction and the north-south direction along the sun, or sliding the light-converging unit in a turbulent direction with the upper surface of the light guide plate.