CN103361257A - Light direction hybrid reinforcement-based novel internal component and photobioreactor - Google Patents

Abstract

The invention provides a light direction hybrid reinforcement-based novel internal component and a photobioreactor. The photobioreactor comprises a transparent housing; a plurality of transparent clapboards which are regularly distributed horizontally and slantwise are arranged along the axial direction in the housing, ladder-shaped local space areas are formed among the clapboards, and the fluid of the center region (a light dark region) of the reactor and the fluid of the surface region (a lighting region) of the reactor generate quick and periodic cyclic motion, so that the hybrid of the fluid along the radial direction (the lighting direction) of the reactor can be enhanced. The light direction hybrid reinforcement-based novel internal component and the photobioreactor provided by the invention have the advantages that the hybrid of the fluid (the alga liquid) along the lighting (light decay) direction can be enhanced, the light dark cycle frequency of the alga cell can be improved, and the light can be abundantly used by the alga cell, various problems when the photobioreactor is amplified can be effectively overcome, and the photobioreactor provided by the internal component can be amplified along the optical path direction.

Description

A novel internal component and photobioreactor based on enhanced light direction mixing

technical field

The invention belongs to the field of microalgae biotechnology, and relates to a novel photobioreactor and its internal mixing components, which can realize high-density and high-yield culture of microalgae. In addition, the present invention can also be used in other cultivation or chemical reaction fields that require light (such as photosynthetic bacteria cultivation, plant cell cultivation, photocatalytic reaction, etc.).

Background technique

Microalgae are rich in protein, polysaccharides, polyunsaturated fatty acids and carotenoids and other high value-added substances. At the same time, microalgae have the ability to absorb N/P elements and accumulate oil during the cultivation process. Therefore, microalgae are important in bioenergy. , Biological carbon sequestration, environmental protection, food, feed and medicine and many other aspects have a wide range of applications. Especially in recent years, in terms of bioenergy, microalgae are considered to be the most promising raw materials for the preparation of biofuels such as biodiesel.

Photobioreactor is the core device of microalgae photoautotrophic culture. The performance of photobioreactor directly affects the cell density and yield of microalgae culture. At present, there are two types of photobioreactors used for microalgae cultivation: open type and closed type. Open photobioreactors mainly refer to open track pools and round pools, which are currently the most widely used reactor types in outdoor large-scale cultivation of microalgae. Although the open photobioreactor has the advantages of easy construction, convenient operation and low operating cost, it also has many disadvantages, such as low algae cell density and yield, difficult control of culture conditions, and easy to be polluted by protozoa. Another type of photobioreactor is the closed photobioreactor. Compared with the open photobioreactor, it has the advantages of high culture density, high cell yield, easy control of culture conditions and less contamination by protozoa. Therefore, closed photobioreactors are widely used in high-density cultivation of microalgae, production of high value-added substances by microalgae and experimental research. In particular, in recent years, the large-scale cultivation of energy microalgae requires a large number of algae species, and the traditional large-scale step-by-step expansion method has problems such as long cycle and easy contamination (which can lead to expansion failure). Therefore, the closed photobiological The reactor is used as a seed expansion device for energy microalgae (algae species that cannot be cultured heterotrophically or with a very slow heterotrophic culture rate), which can greatly reduce the risk of failure in the expansion of energy microalgae seeds, shorten the seed expansion period, and improve Energy microalgal culture efficiency.

At present, there are mainly three types of closed photobioreactors: column type, tube type and plate type. Tubular photobioreactors have a larger specific surface area, and generally can obtain higher algae cell density and productivity. However, the pipeline reactor has poor mixing ability, serious accumulation of dissolved oxygen, and difficulties in inner wall cleaning and maintenance. Compared with the tubular photobioreactor, the column photobioreactor has the advantages of uniform mixing and easy oxygen decomposition, but the main problem is the amplification, which is difficult to enlarge in the longitudinal or radial direction; the flat photobioreactor It has the advantages of large specific surface area for illumination, short optical path, easy oxygen analysis, and relatively easy amplification. In addition, the plate photobiological reaction can adjust the placement angle of the plate reactor according to the angle of sunlight, so that the reactor can fully receive the light. Therefore, the flat-plate photobioreactor is a type of photobioreactor that is currently being researched and developed by various scientific research institutes and companies at home and abroad.

In recent years, domestic and foreign literature and invention patents on flat-panel photobioreactors mainly include:

1) Degen et al. reported an air-lift flat plate photobioreactor (volume 1.5 L, width 1.5 cm) with built-in staggered horizontal partitions. The fluid descending channel is located on one side of the reactor width direction, and the ascending channel is covered 5 horizontal baffles are divided into 6 connected parts. The five baffles are alternately fixed on the front and rear panels of the reactor. When the fluid rises, a vortex will be formed between the two baffles, so that the algae cells circulate periodically between the light area and the dark area. (Degen J, Uebele A, Retze A, et al. A novel airlift photobioreactor with baffles for improved light utilization through the flashing light effect. Journal of Biotechnology, 2001, 92(2): 89-94).

2) Tredici et al. designed a flat-plate photobioreactor with external support made of transparent soft material similar to a plastic bag, which is called Green Wall Panel. This design greatly reduces the manufacturing cost of the photobioreactor, and is suitable for low-cost cultivation of microalgae (WO2004/074423A2).

3) The Solix company in the United States has developed a plate-type photobioreactor placed in water. Its main body is a film bag placed in water. The external water can not only support the bag-type reactor, but also play a good role in temperature control and light intensity distribution. role (US2008/0160591 A1).

4) Li Yuanguang et al. invented a new multi-section flat-plate photobioreactor. There are multiple hollow guide baffle cavities in the reactor. Artificial light sources can be placed inside the cavity. There are intervals. Because the reactor strengthens the mixing of algae cells with the fluid in the light direction, the light utilization efficiency can be significantly improved, and at the same time, the direct contact between the internal light source lamp tube and the culture solution is avoided (CN1880442).

5) Hu et al. invented a flat-panel photobioreactor that is expandable in the length direction. This reactor is composed of several ordinary flat-plate reactor units, and the units are connected by plastic or metal linking members. The reactor can be made into different widths (light path) according to the needs, and can be arranged in a linear or curved form. At the same time, it can be placed at different inclination angles according to the sunlight angle to fully receive the light. (US2010/0028976A1).

6) Subitec Company of Germany designed a flat air-lift photobioreactor. Each unit volume of the reactor is 180L. A fluid vortex is formed in the chamber, which increases the alternating frequency of the algal cells in the light zone and the dark zone, thereby increasing the cell growth rate (Morweiser M, Kruse O, Hankanmer B, et al.Developments and perspectives of photobioreactors for biofuel production.Appliedmicrobiology and Biotechnology, 2010, 87: 1291-1302).

At present, the main problems encountered in the practical application of closed photobioreactors are as follows: 1) high manufacturing and operating costs; 2) difficulty in scaling up. It can be seen from the above-mentioned development trend of flat-plate photobioreactors in recent years that in order to solve the problem of high cost, the materials of the reactor are generally improved, and the previous hard materials such as plexiglass and ordinary glass are developed into soft materials such as plastic films. material, which can significantly reduce the production cost of the reactor. In addition, the lighter and softer material facilitates the movement of the reactor. Aiming at the difficulty of scaling up photobioreactors, there is still no good technical means at present. Generally, when scaling up, the number of small reactor units is increased to increase the overall liquid capacity of the reactor.

Internal mixing components are widely used in pipeline photobioreactors, usually different forms of static mixers, which can make the fluid state in the pipeline reactor change from conventional laminar flow to turbulent flow, so as to improve the algae in the reactor. The degree of mixing of the liquid. However, internal components are generally less used in flat-plate and column reactors, and one or two baffles are generally installed in a flat-plate reactor to form a partition or air-lift flat-plate reactor; A guide tube is generally installed in the reactor to form an air-lift column photobioreactor. These internal components generally make the fluid flow in the reactor orderly, which can promote the growth of algae cells to a certain extent. However, this internal component lacks the effect of making the fluid move in a continuous cycle in the direction of light attenuation, cannot enhance the mixing of the fluid in the direction of light, and has limited ability to improve the ability of algae cells to receive light.

Therefore, there is still a need in the art for a photobioreactor that enables algal cells to make full use of light energy in a limited area (light area) in the reactor, increases the light intensity of algal cells and promotes the photoautotrophic growth of algal cells.

Contents of the invention

The present invention is based on the design concept of strengthening the mixing of fluid (microalgae culture fluid) in the direction of light (light attenuation) in the photobioreactor, focusing on improving the light energy of the algae cells in the reactor and improving the light and darkness of the algae cells. From the perspective of cycle frequency, a photobioreactor with a novel internal structure and its internal components are designed, which can not only realize the high-density and high-efficiency photoautotrophic culture of microalgae, but also realize the effective photobioreactor in the direction of the light path. enlarge.

Therefore, the purpose of the present invention is to provide a kind of can make fluid (alga liquid) produce periodical circulation motion in the light direction (light attenuation direction), thereby make algae cell fully utilize the light energy in the limited area (light zone) in the reactor , to increase the light intensity of algae cells. The invention can not only make the fluid flow in the reactor more orderly, but also greatly promote the mixing intensity of the fluid in the light direction, so that the algae cells can quickly move between the light area and the dark area (due to light attenuation) in the reactor. Move and increase the light-dark cycle frequency of algal cells, which can greatly promote the photoautotrophic growth of algal cells

Specifically, the present invention provides a novel internal component of a photobioreactor and a corresponding photobioreactor, wherein the photobioreactor includes:

Transparent outer casing;

In the axial direction of the casing (that is, the main flow direction of the algae liquid, if the casing is a flat plate placed vertically with the ground, then it is the height direction) there are a number of regularly arranged transparent partitions that are horizontally inclined. The partitions form a certain angle with the wall of the shell, and a trapezoidal local space area is formed between the upper and lower adjacent partitions and the shell. This configuration makes the fluid in the central area of the reactor (light and dark area) and the surface of the reactor Rapid periodic cyclical movement is generated between the fluids in the area (illumination area), which intensifies the mixing of fluids in the radial direction of the reactor (illumination direction); and

Supply gas equipment or other power equipment.

In a specific embodiment, the transparent outer shell is in the shape of a flat plate, a cylinder, a tube, or other shapes.

In a specific embodiment, the internal member is a plurality of regularly arranged transparent partitions inclined horizontally, and a trapezoidal local space area is formed between the partitions. The separator can be hollowed out to form a hollow cavity.

In a specific embodiment, the air supply device or other power devices are air pumps, gas distributors or other related power equipment that can cause the algae liquid to flow in the photobioreactor.

In a specific embodiment, the transparent housing can be made of organic glass, inorganic glass (ordinary glass or toughened glass, etc.) and other transparent materials with certain mechanical strength; or it can be made of soft materials such as transparent plastic films. .

In a specific embodiment, the internal components of the photobioreactor can be solid transparent partitions or hollow partitions. If the partition is a transparent solid plate, it can be separated from the reactor shell, and the partition can be freely inserted into the reactor; if the partition is a cavity partition, it needs to be integrated with the reactor shell.

In a specific embodiment, an artificial light source can be placed in the hollow cavity formed by hollowing out the partition board.

In a specific embodiment, the photobioreactor may further include a temperature detection and control system, a pH detection and feedback control system, a dissolved oxygen detection system, and an internal light intensity detection system.

Another aspect of the present invention also relates to the above-mentioned photobioreactor and its internal components in the fields of microalgae photoautotrophic cultivation (including other cultivation or chemical reactions that require light, such as photosynthetic bacteria cultivation, plant cell cultivation, photocatalytic reactions, etc. ) in the application.

The photobioreactor with novel internal components designed by the present invention (taking the external shell as a flat plate as an example) has orderly fluid movement and mixed light direction compared with conventional flat plate reactors (no internal components, bubbling type) The advantages such as violent, the algae cell growth rate and the algae cell density are obviously higher than the algae cell growth rate and the algae cell density in the conventional plate reactor (see embodiment 1).

Although the above-mentioned air-lift flat plate photobioreactor designed by Degen et al. with built-in staggered partitions can also promote the periodic circulation of fluid in the direction of light, the scale of the reactor is only 1.5L; the internal partitions are placed horizontally, and the flow The field is unreasonable (the reactor partition of the present invention has a certain inclination angle, which makes the flow field more reasonable), which will cause more dead zones; and the partition cannot be separated from the external shell, making it difficult to clean the reactor. In addition, the reactor designed by Degen et al. has a single layer in the width (light path or light path) direction, which is relatively narrow, and cannot be as wide as possible in the light path direction (ie, the direction of light), which is not conducive to the reactor's optical path direction. (the reactor designed in the present invention has two symmetrical parts in the width direction, so that the reactor can be as wide as possible in the width direction).

The air-lift flat plate photobioreactor developed by Subitec also has the problem of difficult cleaning, especially for the cultivation of microalgae that are easy to attach to the wall. The internal components designed in the invention can be disassembled from the reactor shell, which facilitates thorough cleaning of the reactor.

The flat plate reactor designed by Tredici mainly considers reducing the manufacturing cost of the reactor. The reactor shell is made of thin-film soft plastic material, and the soft shell is made of simple thin metal wire or plastic wire on the outside. Support, but there is no internal components inside the reactor, like conventional flat plate reactors, it does not have the ability to promote the mixing of algae liquid in the direction of light.

Similarly, the flat-plate photobioreactor that can be expanded in the length direction invented by Hu is also a conventional flat-plate reactor, and the internal fluid mixing is chaotic and disordered, which is not conducive to the growth of algae cells. Hu's invention is mainly considered from the perspective of reactor enlargement, but its enlargement mainly starts with increasing the number of small reactor units in the length direction of the reactor, not the enlargement of the volume of a single reactor in the traditional sense.

The thin-film plate reactor in water designed by Solix is also a simple bubbling type from the perspective of mixing, and the flow field mixing is disordered. And the reactor is placed in the water body, and the reactor shows that the light intensity is relatively weak, which is not conducive to the cultivation of microalgae that require high light intensity.

The reactor designed in the present invention is mainly considered from the perspective of fluid, with the purpose of strengthening the mixing of algae cells in the direction of light and improving the utilization efficiency of light energy by algae cells. The material of the reactor can be transparent materials such as plexiglass or inorganic glass, or It can be made of soft materials such as plastic film, and the reactor can be enlarged not only from the length direction but also from the width direction. The multi-section flat plate photobioreactor (CN1880442) designed in the past, although it also has the ability to promote the flow of fluid in the radial direction, but because the fluid forms a periodic overall cycle, the cycle period of the fluid in the direction of light is very long, and the frequency Low enough to create a "flash effect" that is beneficial to algal cells. The present invention is a further development of the multi-section flat plate reactor. By adding horizontal and inclined partitions in the reactor, multiple ladder-shaped local spaces are formed, causing the fluid to form a periodic cycle with a relatively fast circulation frequency in each local space. The flow promotes the full acceptance of light by algae cells.

In summary, compared with other photobioreactors, the present invention focuses on the consideration of strengthening the mixing of fluid in the direction of illumination in the reactor, so as to facilitate the amplification of the reactor in the light path direction, which is important for photobioreactor amplification and microalgae. The photoautotrophic culture of is very critical. From the perspective of cost reduction, the reactor designed by the present invention can be made of cheap soft film material; to zoom in.

In a word, aiming at the shortcomings of existing closed photobioreactors such as poor mixing performance in the light direction and difficult amplification, the present invention uses the axial direction in the reactor shell (that is, the main flow direction of the algae liquid, if the shell is placed perpendicular to the ground) The method of arranging multiple regularly arranged horizontally inclined transparent partitions to strengthen the mixing of the fluid in the radial direction of the reactor (direction of light) makes it possible to install this new type of internal component. The photobioreactor has unique advantages such as scalability in the direction of light path, strong periodic circulation of fluid in the light direction, and rapid growth of algae cells.

Brief description of the drawings

Figure 1 shows a series of new photobioreactors (side view) formed by applying internal components to flat-plate photobioreactors. The meanings of the symbols are as follows: w is the width of the reactor, h is the height of the reactor, h0 is the distance from the vent pipe to the bottom, h1 is the lower edge of the partition (type b) and the lower edge of the baffle (type a and c) The distance from the bottom of the reactor, h2 is the distance from the top of the partition (type b) and the bottom of the partition (type a and c), h3 is the distance between the two partitions, h4 is the distance between the partition (type b ) and the distance from the top of the baffle (type a and c) to the top of the reactor, w1 is the distance between the two partitions in the horizontal direction (type b), w2 is the distance between the partition and the reactor wall (type a and c), w3 is the distance between the two baffles (type c), and α0 is the intersection angle between the partition and the wall.

Figure 2 shows the physical picture of the flat plate photobioreactor with the new internal structure and the control reactor.

Fig. 3 shows the internal flow field of the flat plate photoreactor with the new internal structure and the control reactor (calculated by computational fluid dynamics software).

Figure 4 shows the comparison of the chlorella culture process between the new internal structure plate reactor and the control reactor.

specific implementation plan

Generally speaking, light is the most critical factor affecting the photoautotrophic growth of algal cells. The algal cells in the photobioreactor will absorb light, and at the same time, the mutual occlusion between the algal cells will cause the light to decay exponentially with the increase of the optical path (depth of culture solution) and cell concentration. Therefore, there is Light zone (the area where the light intensity is sufficient for the growth of algae cells) and dark area (the area where the light intensity is lower than that required for the growth of algae cells). Strengthening the movement frequency of algae cells between the light area and the dark area is beneficial to the algae cells receiving as much light as possible and increasing the growth rate of the algae cells. This phenomenon is called "Flashing Light Effect". Therefore, the frequency of light-dark cycles has become an important parameter in the design of photobioreactors. There are generally two ways to increase the frequency of light-dark cycles in the reactor: 1) Increase the mixing intensity in the reactor so that algae cells can Complete the movement from the dark area to the light area; 2) Set internal components (such as static mixers, baffles, etc.) The cells move periodically among the small units, thereby increasing the light-dark alternation frequency of the algae cells.

The present invention designs a novel internal component, which is mainly a series of partitions arranged in an orderly manner according to certain rules, which can cause the algae liquid to move periodically and rapidly in the direction of light, strengthen the mixing of algae cells in the direction of light, and improve the efficiency of algae. The light-dark cycle frequency of the cells, thereby increasing the growth rate of algae cells.

Specifically, the present invention provides a novel internal component and a corresponding photobioreactor. The photobioreactor includes a transparent casing; inside the casing are arranged a plurality of groups of transparent compartments arranged regularly. Plates, which form a trapezoidal local space area, can cause rapid periodic circulation between the fluid in the central area of the reactor (light and dark area) and the fluid in the surface area of the reactor (light area), and strengthen the fluid in the reaction. The mixing in the radial direction of the device (ie, the direction of light); and the supply of gas devices or other power devices. The multiple sets of transparent partitions can cause the fluid to perform rapid periodic circulation in it, and strengthen the mixing of the fluid in the radial direction of the reactor (ie, the direction of light).

It should be understood that the "trapezoidal" mentioned herein means that viewed from the section of the reactor, the area formed by the wall of the reactor and the adjacent upper and lower partitions is trapezoidal.

The invention has the advantages of strengthening the mixing of fluid (algae liquid) in the light direction, increasing the light-dark cycle frequency of algae cells and the full utilization of light energy by algae cells, and can effectively overcome the problems that occur when the photobioreactor is enlarged in the direction of light path. Problems (e.g. algal cells inside the reactor do not receive sufficient light, decreased cell yield, etc.).

The implementation method of the present invention will be described in detail below from different aspects.

1) Composition and structure of internal components

The internals consist of a series of baffles (plates placed obliquely horizontally in the reactor) or baffles plus baffles (plates placed vertically in the reactor). The partition includes a partition directly in contact with the wall of the reactor and a partition separated from the wall by a distance w2, preferably, the two partitions appear alternately. The horizontal length of each partition preferably does not exceed half of the width w of the reactor. Each partition forms a certain angle α0 with the wall of the reactor, and the angle α0 formed between each partition and the wall can be the same or different, but the distance between the adjacent upper and lower partitions and the central axis of the reactor wall and the reactor (refer to the attached The vertical dotted line of type b in Figure 1) will form a trapezoidal area, in which the liquid (algae liquid) will form a periodic cycle in this special space area, so that the algae cells are in the center of the reactor (inside the reactor, generally Dark area) and the near-wall area (the outside of the reactor, generally the light area) perform continuous circular motion, so that the algae cells can make full use of the light energy in the near-wall area.

In a specific embodiment, the internal components of the present invention, as shown in Figure 1 type b, include a partition in contact with the wall and a spacer with a certain angle separated from the two walls by a distance w2, so that the adjacent upper and lower A trapezoidal region is formed between the partitions, the reactor wall, and the central axis of the reactor. Multiple groups of slots can be arranged on both side walls (width direction) of the photobioreactor, and the partitions can be fixed by inserting the partitions into the slots; independent composite members can also be made (all partitions and The baffles are combined to make an integral component that can be detached from the outer shell, and the combined integral component can be directly inserted into the shell when in use). In this way, it is convenient to take out the partition or take out the entire internal components, so as to facilitate the thorough cleaning of the reactor and the partition. In order to enhance the overall mixing in the reactor, the internal components can be adjusted appropriately, changing it from all the partitions to some partitions and baffles, and the flow channel is formed between the baffles and the wall or between the baffles, so that the fluid With integral circulation, it improves the overall mixing effect in the reactor.

Exemplary examples of internals containing baffles may be shown in Figure 1 Types a and c. Type a includes a baffle, part of the baffle is in contact with the reactor wall, and part of the baffle is in contact with the baffle. These two types of baffles each form a certain angle α0 with the reactor wall and the baffle, and α0 can be the same or different, but A trapezoidal area is formed between the adjacent upper and lower partitions, the reactor wall and the baffle; in addition, there is a certain distance w2' (in the horizontal direction) between the partition and the baffle in contact with the reactor wall, and the contact with the baffle There is a certain distance w2 between the partition and the reactor wall, and w2' and w2 can be the same or different. Preferably, the length of each partition in the horizontal direction does not exceed half the width w of the reactor. More preferably, the length of the partition in the horizontal direction plus w2 or w2' is equal to or less than half the width w of the reactor.

Typically, when the internals including the baffles are placed within the reactor, they are placed on the central axis of the reactor.

In accompanying drawing 1 type c, two baffles are placed in the reactor, part of the baffle is in contact with the reactor wall, and part of the baffle is in contact with the first baffle and the second baffle respectively. The reactor wall and the corresponding baffle form a certain angle α0, and α0 can be the same or different, but a trapezoidal area is formed between the adjacent upper and lower partitions, the reactor wall and the corresponding baffle. The distance between two baffles can be optimized by technicians according to actual production conditions. It should be understood that at this time, the length of each partition in the horizontal direction and the distance between the partition and the reactor wall and baffle should be adjusted appropriately.

The shape of the partitions can vary depending on the type of reactor. For example, for a flat plate reactor, the partitions may be square. For a column or pipe reactor, the partition can be fan-shaped, so that the side in contact with the reactor shell can be arc-shaped to match the shell.

For column or tube reactors with baffles, the baffles themselves can be square or cylindrical. When the baffle is square, the side where the partition contacts the baffle should also be square, while the other side can be curved. While the baffles are cylindrical, the partitions may be fan-shaped.

The distance h1 from the bottom of the partition (type b) and the bottom of the baffle (type a and c) to the bottom of the reactor, the distance from the bottom of the partition (type b) and the bottom of the partition (type a and c) h2, the distance between the partitions h3, the distance between the partition (type b) and the upper edge of the baffle (type a and c) from the top of the reactor h4, the horizontal distance between the two partitions (type b) w1 , the distance between the partition and the reactor wall (type a and c) w2, the distance between the two baffles (type c) w3, the intersection angle α0 between the partition and the wall and other structural parameters can be optimized and adjusted to obtain the most The size of the optimal structure. Those skilled in the art can also select an appropriate number of partitions and/or baffles according to the size of the photobioreactor to form an appropriate number of trapezoidal regions in the photobioreactor.

In a specific embodiment, taking a 15L flat-plate photobioreactor as an example, the length of the reactor is 25cm, the width w is 15cm, and the height h is 40cm. The range of h1 is 1-20cm, the range of h2 is 1-20cm, the range of h3 is 1-20cm, the range of h4 is 1-10cm, the range of w1 is 0.5-10cm, the range of w2 is 0.5-6cm, the range of w3 The range is 1-12cm, and the angle of α0 is 1-85°. In a preferred embodiment, the range of h1 is 1-10 cm, the range of h2 is 1-15 cm, the range of h3 is 1-8 cm, the range of h4 is 1-8 cm, the range of w1 is 0.5-5 cm, and the range of w2 The range is 0.5-4cm, the range of w3 is 1-6cm, and the angle of α0 is 45-85°.

In addition, in order to prevent the formation of a dead zone in the angled area between the partition plate and the reactor shell, there may be small gaps or small holes between the partition plate and the reactor shell, so that the fluid can flow in the angled area. At the same time, the partitions and baffles are made of transparent materials, and the thickness is relatively thin, so as to reduce the absorption and shading of light. In addition, the partitions and baffles can be separated from the outer shell, and can be disassembled independently and taken out from the shell, so as to clean the reactor and internal components.

2) The main structure and material of the reactor

The main structure (shell) of the photobioreactor can be flat plate, column or pipeline. The internal components can be properly adjusted according to the shape of the external shell. Compared with other closed photobioreactors, the flat photobioreactor has the advantage of being relatively easy to scale up, therefore, the internal components of the present invention are firstly applied in the flat photobioreactor. The outer shell of the photobioreactor is made of transparent materials, which can be hard materials such as plexiglass, inorganic glass (common tempered glass, etc.), or soft materials such as plastic films. If soft materials are used, support structures such as metal mesh need to be installed outside the reactor.

3) Built-in artificial light source in the baffle and partition cavity

Baffles and baffles can be made into hollow cavities. In this way, baffles and baffles not only affect the flow of fluid in the reactor, promote the mixing of fluids in the direction of light, but also serve as places for placing artificial light sources. The baffle and partition in the form of a hollow cavity can increase the specific surface area of the reactor on the one hand, and on the other hand can avoid the direct contact between the artificial light source and the algae liquid, so as to avoid many problems caused by the direct contact between the light source and the liquid. For example, the algae cells are attached to the surface of the light source; at the same time, the artificial light source is placed in the cavity, so that the artificial light can be fully absorbed and utilized by the algae cells in the reactor.

4) Power device and detection system

When the shell of the photobioreactor is flat or cylindrical, the algae solution in the reactor is mixed by ventilation, and when the shell of the reactor is pipeline, it is generally passed through a pump device or an air lift system. Make the algae solution flow in the pipeline. In addition, various detection and control systems can be configured in the photobioreactor, such as temperature detection and control system, pH detection and feedback control system, dissolved oxygen detection system and light intensity detection system.

The structure of the novel internal mixing member of the present invention and the photobioreactor and its internal mixing situation (especially the unique fluid vortex in the direction of illumination) will be further described below in conjunction with the accompanying drawings.

Figure 1 is a series of novel flat-panel reactors (structural schematic diagram, side view) formed by applying internal mixing components to flat-panel photobioreactors. Fig. 2 is a physical picture of a flat plate reactor with a novel internal structure and a control reactor. The internal components of the type a reactor are composed of a central baffle and an inclined partition. The left side of the reactor is a descending channel, and an inclined partition placed up and down is added to the channel to promote the mixing of the algae liquid in the direction of light. At the same time, the right side is the fluid Ascending channel, the whole reactor can realize integral flow. The internal components in the type b reactor are built-in inclined partitions that are staggered up and down, and a trapezoidal area is formed between the partitions in the vertical direction; at the same time, the left and right sides of the reactor are basically symmetrically distributed. The type c reactor is also composed of baffles and inclined partitions. Two baffles form a fluid ascending channel in the center of the reactor, and there are two fluid descending channels on both sides close to the inner wall of the reactor. The inclined partitions are used to promote the mixing of algae liquid in the direction of light.

Fig. 3 is the flow field distribution in various types of flat photobioreactors (calculated by CFD calculation software Ansys12.0CFX, under the condition that the ventilation rate is 1.0vvm).

A type a reactor has 1 bulk flow loop with a small fluid loop above it as in reactor b. The large circulation of fluid interacts with many small circulations and mixes with each other. The liquid in the type a reactor mainly flows vertically (axially) in the left channel, and the radial flow and mixing of the liquid are more obvious in the right channel of the reactor due to the fluid circulation. Type a is formed on the basis of a single-baffle air-lift reactor (multiple sets of horizontally inclined partitions are added to the descending channel of the single-baffle air-lift reactor). It can be seen from Figure 3 that there is only one overall flow cycle in the single-baffle airlift reactor, and the fluid flow is mainly in the axial direction, and the flow in the radial direction (light direction) is very weak, which is not conducive to the light of microalgae. Autotrophic growth.

The type b reactor is divided into many special "chambers" (the space between two partitions) by internal partitions, and the gas basically flows upwards along the inclined partitions due to buoyancy (the internal partitions are similar to gas flow. Deflector), driven by the gas, the fluid (referring to the liquid) in each "cell" can produce a rapid periodicity between the central area of the reactor (light and dark area) and the surface area of the reactor (light area) circular movement. There is no partition between the two "chambers" on the same layer, so the two fluid cycles on the same layer interact and blend with each other, making the two cycles not very regular. The liquid in the type b reactor mainly circulates periodically in each chamber, and the flow in the radial (light) direction is very obvious, which is conducive to the algae cells in the dark area to fully accept and utilize the light in the light area. Improve the light energy utilization efficiency of algae cells. The type b reactor can be regarded as formed on the basis of the bubble reactor (multiple groups of staggered and horizontally inclined partitions are added to the bubble reactor), as can be seen from Figure 3, the plate reaction of the control group The fluid in the reactor (that is, bubbling type, without internal components) forms two large cycles. The fluid mainly flows vertically up and down, and only flows in the radial direction (ie, the direction of light) at the top and bottom of the reactor.

A type c reactor has two overall flow loops with many small loops above them. In the reactor, the liquid flows in the axial direction in the ascending channel, and the axial and radial movements are relatively strong in the descending channels on both sides. Type c is formed on the basis of a double-baffle air-lift reactor (multiple sets of horizontally inclined partitions are added on both sides of the descending channel of the air-lift reactor). It can also be seen from Figure 3 that there are two overall flow cycles in the double-baffle airlift reactor, and the fluid flow is mainly in the axial direction, and the flow in the radial direction (light direction) is weak, which is not conducive to microalgae photoautotrophic growth.

It can be seen that the liquid in the control group reactor (bubble type), the single-baffle and double-baffle airlift reactors all flow mainly in the axial direction, and the liquid in the type b reactor mainly flows in the radial direction , the axial and radial flow of liquid in type a and c reactors are relatively obvious.

In order to describe in detail the advantages of the novel internal components and photobioreactors thereof of the present invention, an example will be used to describe them below:

Embodiment 1: Comparison of the photoautotrophic culture process of chlorella in the new flat plate reactor and the control reactor

Fill 14L tap water into 3 flat-panel photobioreactors with different internal components and 1 control reactor respectively, add 2ml sodium hypochlorite solution (available chlorine content 10%), after ventilating and mixing, treat for 12 hours, then add sulfur Sodium sulfite neutralizes the remaining sodium hypochlorite. After checking with potassium iodide starch test paper, it is determined that there is no sodium hypochlorite (generally excessive sodium thiosulfate), and then continue to ventilate for a period of time to oxidize the excessive sodium thiosulfate, and then put microalgae in the reactor. The photoautotrophic culture medium (f/2 medium) was fully mixed and then added with Chlorella pyrenoidosa seeds, and the photoautotrophic culture started. The initial algal cell density is about 0.15g/L, the ventilation rate is 1.0vvm, and there is light on both sides of the plate reactor, and the light intensity on each side is 10klx.

It can be seen from Figure 4 that the growth of algal cells in the control reactor (without internal components) is the worst, and the highest algal cell density is only 0.916g/L. The growth of algal cells in the three reactors with different internal components was better than that in the control reactor. The highest cell density of microalgae in type b reactor was 1.311g/L, and the highest cell density of microalgae in type a reactor was 1.311g/L. The density is 1.189g/L, and the highest cell density of microalgae in type c reactor is 1.241g/L. At the same time, the specific growth rate of algal cells in four different plate reactors in the exponential growth stage was calculated, and the result was that the specific growth rate of algal cells in the control reactor was 0.051h ^-1 , and the specific growth rate of algal cells in the type b reactor The growth rate was 0.0619h ^-1 , the specific growth rate of algal cells in type a reactor was 0.0574h ^-1 , and the growth rate of algal cells in type c reactor was 0.0604h ^-1 . It can be seen from the above data that the highest density and growth rate of algae cells in the plate reactor with the new internal components are significantly higher than that of the ordinary plate photobioreactor (bubble type, without any internal components). It can be seen that the new internal components designed by the present invention and the new flat plate reactor with internal components added have very good cultivation effects.

It should be understood that although the present invention has been described in the form of specific embodiments, appropriate changes can be made to the present invention without departing from the spirit and scope of the present invention, and these changes are all within the protection scope of the present invention.

Claims (10)

1. a bioreactor is characterized in that, described bioreactor comprises:

Transparent outer hull; With

Internals, described internals is included in and axially is mounted with the regularly arranged lamina of septum pellucidum that is horizontal tilt of polylith in the described housing, the angle that described dividing plate and shell wall side form is so that form the local space zone of trapezoidal shape between neighbouring dividing plate and the housing, the arrangement of described lamina of septum pellucidum makes between the fluid in the fluid in reactor center zone and reactor surface zone and produces fast cyclial movenent.

2. bioreactor as claimed in claim 1 is characterized in that, described transparent outer hull is flat, column type, duct type and other shape.

3. bioreactor as claimed in claim 1 is characterized in that, described dividing plate is hollowed out the formation hollow cavity.

4. bioreactor as claimed in claim 1 is characterized in that, described device of air or other power set of giving is air pump and gas distributor or other relevant power-equipment that can cause algae liquid to flow in bioreactor.

5. bioreactor as claimed in claim 2 is characterized in that, described transparent shell is by the transparent material with certain physical strength; Or made by flexible material.

6. bioreactor as claimed in claim 3 is characterized in that, if dividing plate is the transparent solid plate, then described dividing plate can split with shell of reactor, and dividing plate can freely be inserted in the reactor; If dividing plate is the cavity body dividing plate, then described dividing plate and shell of reactor are integrated.

7. bioreactor as claimed in claim 3 is characterized in that, and is described by placing source of artificial light in the cavate hollow cavity of dividing plate.

8. bioreactor as claimed in claim 1, it is characterized in that described bioreactor also comprises supply gas device or other power set, temperature detection and Controlling System, pH detection and feedback control system, dissolved oxygen detection system and inner light intensity detection system.

9. a member that is used for the described bioreactor of claim 1 is characterized in that described member is the regularly arranged lamina of septum pellucidum that is horizontal tilt of polylith, forms the local space zone of trapezoidal shape between each dividing plate.

10. each described bioreactor of claim 1-8 or member claimed in claim 9 shine into capable cultivation or the application in the chemical reaction at light requirement.

Images