A photobioreactor for culturing microalgae and a control method thereof

Abstract

The present invention relates to the technical field of microbial culture, and specifically to a photobioreactor for culturing microalgae and a control method thereof. The reactor of the present invention comprises a base frame, a bracket is fixedly installed on the top of the base frame, the bracket consists of a lower plate, an upper plate and a connecting rod fixedly connecting the upper plate and the lower plate, a pipe tube is installed on the lower plate, a circulating flow mechanism is provided at a position corresponding to the tube on the upper plate, and a culture tube is provided between the corresponding tube and the circulating flow mechanism, the culture tube consists of an outer tube and an inner tube, a clamping reversing mechanism and a light source mechanism are provided between the upper plate and the lower plate, and a rotating mechanism for driving the culture tube to continuously rotate is provided between the base frame and the bracket. The control method of the present invention comprises establishing a photobioreactor; starting culture; regulating and controlling culture conditions and re-culturing. The present invention allows carbon dioxide to fully contact with microalgae by allowing algae liquid to flow back and forth, and can also promote photosynthesis of the microalgae.

Description

Technical Field

[0001] The invention relates to the technical field of microorganism cultivation, in particular to a photobioreactor for cultivating microalgae and a control method thereof. Background Art

[0002] Microalgae are a type of single-cell algae that can achieve photoautotrophy. They can effectively use light energy, CO2 and inorganic salts to synthesize proteins, fats, carbohydrates and a variety of high-value-added bioactive substances. By cultivating microalgae, medicines, cosmetics, health products and other products can be produced, which has good economic benefits. Therefore, it is necessary to research and develop new and efficient photobioreactors and high-density cultivation of microalgae.

[0003] The prior art discloses a Chinese patent with publication number CN 116554991 A: a photobioreactor and a method for cultivating microalgae, and discloses a micro-nano aeration component, which reduces the diameter of generated bubbles by a rotating micro-nano aeration disk, enhances the gas-liquid mass transfer effect, and at the same time, cooperates with the rotating stirring action of the impeller to reduce the adhesion of microalgae to the inner wall of the reactor, and the bubbles can play a further flushing role, effectively avoiding the problem of light blocking caused by microalgae sticking to the wall.

[0004] However, the above-mentioned prior art still has certain defects. That is, during use, although the impeller rotating stirring method can avoid the light blocking problem caused by microalgae sticking to the wall, it is easy to cause local excessive concentration of microalgae, which will also cause the problem of light blocking. In addition, a rotating micro-nano aeration disk is used to reduce the diameter of the generated bubbles, but most of the bubbles do not burst, resulting in insufficient contact between the reaction gas and the microalgae. Summary of the invention

[0005] The object of the present invention is to provide a photobioreactor for culturing microalgae and a control method thereof, so as to solve the problems raised in the above background technology.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A photobioreactor for culturing microalgae, comprising a base frame, a bracket fixedly mounted on the top of the base frame, the bracket consisting of a lower plate, an upper plate and a connecting rod fixedly connecting the upper plate and the lower plate, the lower plate being penetrated by a plurality of row pipes and tube holders evenly distributed in an annular shape, and the row pipes and tube holders are alternately distributed, and a splash-proof plate rack is fixedly mounted on the inner side of the base frame at a position corresponding to each row pipe;

[0008] A circulation flow mechanism for promoting the flow of culture fluid is provided at the position corresponding to each trustee on the upper plate, and a culture tube is provided between the corresponding trustee and the circulation flow mechanism, the culture tube consists of an outer tube and an inner tube, and a connecting column is fixed between the inner side of the outer tube and the outer side of the inner tube;

[0009] The circulation mechanism includes a limit frame fixed at the corresponding trusteeship position on the bottom of the upper plate and a second cylinder fixedly installed at the corresponding trusteeship position on the top of the upper plate, and a piston matched to the inner diameter of the inner tube is fixedly connected to the telescopic end of the second cylinder;

[0010] A clamping and reversing mechanism for driving the culture tube to switch positions and a light source mechanism for providing light to the microalgae inside the culture tube are provided between the upper plate and the lower plate, and the clamping and reversing mechanism is composed of a reversing driving part and a tube clamping part;

[0011] The light source mechanism comprises a cover frame and a lamp tube installed at an axial position inside the cover frame, a column foot is fixedly connected between the cover frame and the lower plate, a light guide plate corresponding to the culture tube is fixedly embedded on the outside of the cover frame, and a plurality of shielding blocks are equidistantly arranged from top to bottom on the inside of the light guide plate;

[0012] A U-shaped frame is fixedly provided on the inner side of the cover frame at a position corresponding to the light guide plate, and a filter is fixedly embedded at a position corresponding to the light transmission area on the light guide plate in the middle of the U-shaped frame, and the filter is composed of red, green and blue three-color filter sheets arranged in sequence from top to bottom, and electric push rods are fixedly installed at the positions corresponding to each filter sheet on both sides of the U-shaped frame, and the telescopic end of each electric push rod is fixedly connected to an L-shaped shielding plate;

[0013] A rotating mechanism for driving the culture tube to continuously rotate is arranged between the base frame and the bracket, and the rotating mechanism is composed of a rotating driving part and a docking clamping part.

[0014] In a preferred embodiment, the tube clamping portion includes a column fixed at the top edge of the lower plate and a ring plate located at the top of the column, a ring groove is provided at the bottom of the ring plate, and the top of the column is slidably connected to the inside of the ring groove, a semicircular groove corresponding to the culture tube is provided on the inner side of the ring plate, and an arc-shaped groove is provided in the middle of the inner side of the semicircular groove;

[0015] Arc plate one and arc plate two are movably inserted at the two ends of the inner side of the arc-shaped groove respectively, and limiting arc bars for limiting arc plate one and arc plate two at the ends are fixedly provided at both ends of the inner side of the arc-shaped groove, and gear two driven by a servo motor is rotatably installed in the middle part of the inner side of the arc-shaped groove, and arc-shaped rack one meshing with gear two is fixedly provided on the opposite end surfaces of arc plate one and arc plate two, and clamping blocks are fixedly provided on the inner sides of the opposite ends of arc plate one and arc plate two.

[0016] In a preferred embodiment, the reversing drive unit includes a support plate fixedly sleeved on the outside of the connecting rod, a servo motor is fixedly installed on the top of the support plate, the output shaft end of the servo motor is fixedly connected to gear three, and an arc-shaped rack two meshing with gear three is fixedly provided at the position on the outside of the ring disk corresponding to the support plate.

[0017] In a preferred embodiment, the rotation driving part includes a driving motor installed on the inner side of the base frame corresponding to the position of the lamp tube, the output shaft end of the driving motor is fixedly connected to gear 1, and the outer side of each tube is fixedly sleeved with a gear ring meshing with gear 1, the tube is rotatably installed on the lower plate through a bearing, and the outer side of each tube located on the upper and lower end surfaces of the lower plate is fixedly sleeved with a limiting ring plate.

[0018] In a preferred embodiment, the docking clamping part includes a cylinder 1 fixedly mounted on the bottom of the cover frame and a ring block fixedly sleeved on the bottom end of the outer side of the culture tube, the telescopic end of the cylinder 1 is fixedly connected with a lifting plate, and the column foot at the bottom end of the cover frame movably penetrates the lifting plate, a clamping hole is penetrated on the ring block, and a turning plate driven by a servo motor is rotatably mounted at the position of the inner side of the culture tube corresponding to the ring block;

[0019] The docking clamping part also includes a ring movably mounted on the outside of the hosting tube, a T-shaped ring groove is opened on the outside of the ring, a T-shaped clamping plate slidably installed in the T-shaped ring groove is fixedly provided at the position of the outer side of the lifting plate corresponding to the ring, a clamping cylinder is fixedly provided at the position of the clamping hole on the ring block corresponding to the position of the top of the ring, a clamping column penetrating the ring is movably mounted inside the clamping cylinder, and the bottom end of the clamping column is fixedly connected to the limiting ring plate located above the lower plate on the outer side of the corresponding hosting tube.

[0020] In a preferred embodiment, an air supply mechanism is provided on the inner side of each of the tubes, and the air supply mechanism includes a plug fixedly arranged on the inner side of the tube, and an air supply pipe fixed on the base frame is rotatably mounted on the bottom end of the plug, and an annular groove is opened on the inner side of the plug, and a diffusion disk and a positioning piece for fixing the diffusion disk are movably embedded in the annular groove.

[0021] In a preferred embodiment, the positioning member includes a column fixed on the inner side of the annular embedding groove and a through hole provided on the diffusion plate, and the column is provided inside the corresponding through hole, a through groove is provided on the outer side of the column, a square groove connected to the through groove is provided on the top of the column, a square column is movably provided inside the square groove, and a circular plate and a push block are fixedly connected at both ends of the square column respectively;

[0022] The inside of the through groove is movably sleeved with two trapezoidal blocks and two ear blocks fixedly arranged in the middle of the inner side of the through groove, springs are fixedly connected between the opposite sides of the two trapezoidal blocks and the ear blocks, V-shaped grooves are opened on both sides of the push block, and elastic clamps are arranged at the positions of the inner side of the through groove corresponding to the V-shaped grooves.

[0023] The present invention also provides a method for controlling the above-mentioned photobioreactor for culturing microalgae, which specifically comprises the following operating steps:

[0024] S1. Establish a photobioreactor: inject culture solution and target microalgae species into the culture tube, place the culture tube above the tube, and adjust the light intensity and carbon dioxide supply rate;

[0025] S2, start the culture: use the drive motor to drive the gear 1 to rotate, so that the culture tube rotates under the drive of the gear 1, and at the same time, use the cylinder 2 to push the piston into the inner tube, and reciprocate and lift the inner tube, so that the algae liquid flows back and forth between the inner tube and the outer tube;

[0026] S3. Cultivation condition regulation: The optical density method is used to measure the biomass changes during the microalgae cultivation process, and the supply surface of different color lights and the carbon dioxide supply rate are adjusted according to the measured values;

[0027] S4. Re-cultivation: After the initial cultivation is completed, the bottom opening of the culture tube is blocked by a flip plate, and the tube clamping part is driven by the reversing drive part to switch the culture tube from the tube holder to the discharge tube, discharge the algae liquid, and then inject new culture liquid, and use the initial algae liquid trapped inside the tube holder as the algae seed for re-cultivation.

[0028] Beneficial effects of the present invention:

[0029] 1. The present invention uses a driving motor to drive the first gear to rotate, so that the culture tube rotates under the drive of the first gear, ensuring that the microalgae in each area inside the culture tube can be fully irradiated by the light source. At the same time, the second cylinder is used to push the piston into the inner tube, and the inner tube is reciprocated and lifted, so that the algae liquid flows back and forth between the inner tube and the outer tube, and the shielding block is used to divide the light receiving area of ​​the culture tube into a plurality of light and dark alternating areas, so that the flowing algae liquid repeatedly circulates between the light and dark areas to form a flash effect, promote the photosynthesis of the microalgae, and can also use the pressure of the reciprocating flow of the algae liquid to squeeze the bubbles to release carbon dioxide, so that the microalgae and carbon dioxide are fully in contact, and the utilization rate of carbon dioxide is improved;

[0030] 2. The present invention can realize precise control of lighting conditions by using red, green and blue three-color filter monoliths arranged in sequence from top to bottom as the filter, and using an electric push rod to push the corresponding L-shaped shield to independently adjust the light-transmitting surfaces of the red, green and blue three-color filter monoliths on the filter in the area;

[0031] 3. The present invention utilizes the rotating gear 2 to drive the arc plate 1 and the arc rack 1 on the arc plate 2 to move in opposite directions along the arc groove, thereby driving the arc plate 1 and one end of the mounting clamp on the arc plate 2 to extend out of the arc groove, thereby completing the rapid clamping and fixing of the culture tube;

[0032] 4. The present invention arranges a detachable diffusion disk on the inner side of the plug, which can realize quick installation and fixation of the diffusion disk, and is convenient for later cleaning. The arrangement of the diffusion disk can guide the bubbles generated in the process of supplying carbon dioxide gas to diffuse in a ring shape to the pore area, and use the pore area to squeeze the bubbles to release carbon dioxide to fully contact with the microalgae. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 is an overall top view of the present invention;

[0036] Figure 3 The present invention Figure 2 Schematic diagram of the cross-sectional structure in the middle AA direction from the first perspective;

[0037] Figure 4 The present invention Figure 2 Schematic diagram of the cross-sectional structure in the middle AA direction at the second viewing angle;

[0038] Figure 5 This is a schematic diagram of the structure of the culture tube and the trusteeship of the present invention;

[0039] Figure 6 The present invention Figure 5 Schematic diagram of the longitudinal section structure;

[0040] Figure 7 It is a schematic diagram of the structure of the light source mechanism of the present invention;

[0041] Figure 8 It is a schematic diagram of the local structure of the rotating mechanism of the present invention;

[0042] Fig. 9 It is a schematic diagram of the overall structure of the positioning member of the present invention;

[0043] Fig.10 It is a schematic diagram of the local structure of the longitudinal section of the positioning member of the present invention;

[0044] Fig.11 It is a schematic diagram of the local structure of the transverse section of the positioning member of the present invention;

[0045] Fig.12 The present invention Figure 3 A' part of the structure is enlarged schematic diagram;

[0046] Fig.13 It is a schematic diagram of the structure of the clamping reversing mechanism of the present invention;

[0047] Fig.14 It is a schematic diagram of the local structure of the transverse section of the clamping reversing mechanism of the present invention.

[0048] The reference numerals in the figure are as follows: 1. chassis; 2. bracket; 21. lower plate; 22. upper plate; 23. connecting rod; 231. L-shaped rod; 232. connecting sleeve; 3. rotating mechanism; 31. gear one; 32. gear ring; 33. lifting plate; 34. collar; 35. clamping cylinder; 36. clamping hole; 37. cylinder one; 4. clamping reversing mechanism; 41. column; 42. ring plate; 43. arc groove; 44. arc plate one; 45. arc plate two; 46. gear two; 47. arc rack one; 48. clamping block; 49. limiting arc bar; 410. bracket; 411. gear three; 412. arc rack two; 5. circulating flow mechanism; 51. limit frame; 52. cylinder 2; 53. Piston; 6. Light source mechanism; 61. Lamp tube; 62. Cover frame; 63. Light guide plate; 64. U-shaped frame; 65. Block; 66. Electric push rod; 67. L-shaped shield; 68. Filter; 7. Air supply mechanism; 71. Plug; 72. Air supply pipe; 73. Diffuser; 74. Positioning piece; 741. Column; 742. Round plate; 743. Square column; 744. Groove; 745. Trapezoidal block; 746. Ear block; 747. Spring; 748. Push block; 749. V-shaped groove; 7410. Elastic clamp; 8. Drain pipe; 9. Trustee; 10. Culture tube; 11. Splash-proof tray rack; 12. Flip tray; 13. Ring block; 14. Limiting ring plate. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The microalgae culture of the present invention belongs to a type of biological industry, wherein the photobioreactor is a part of a culture device for culturing photosynthetic microorganisms and tissues or cells with photosynthesis ability, and is used for culturing microalgae. Example

[0051] Refer to the instruction manual Figure 1-Figure 4A photobioreactor for culturing microalgae according to an embodiment of the present invention comprises a base frame 1, a bracket 2 is fixedly mounted on the top of the base frame 1, the bracket 2 is composed of a lower plate 21, an upper plate 22 and a connecting rod 23 fixedly connecting the upper plate 22 and the lower plate 21, wherein the connecting rods 23 are evenly distributed in a ring shape and have a plurality of groups, each group of connecting rods 23 is composed of two L-shaped rods 231 and a connecting sleeve 232 threadedly connected to the outer side of the butt ends of the two L-shaped rods 231, and the butt ends of the two L-shaped rods 231 are designed to be plug-in, which is convenient for quick alignment, and the bracket 2 is placed on the bottom of the base frame 1. The frame 2 is designed as a two-stage structure, which is convenient for quick disassembly and assembly of the culture tubes. The lower plate 21 is installed with multiple row pipes 8 and tube holders 9 that are evenly distributed in a ring shape, and the row pipes 8 and tube holders 9 are alternately distributed. A liquid inlet pipe is provided at the position corresponding to each row pipe 8 on the upper plate 22. The inner diameter of the liquid inlet pipe is smaller than the inner diameter of the row pipe 8, and the opposite end faces of the liquid inlet pipe and the row pipe 8 are arranged horizontally and coplanarly. A splash-proof plate frame 11 is fixedly provided on the inner side of the bottom frame 1 at the position corresponding to each row pipe 8 to prevent the algae liquid from splashing out of the bottom frame 1 during the discharge process.

[0052] Specifically, Figure 3 and Figure 12-14 As shown, a clamping reversing mechanism 4 for driving the culture tube 10 to switch positions is provided between the upper plate 22 and the lower plate 21. The clamping reversing mechanism 4 is composed of a reversing driving part and a tube clamping part;

[0053] The pipe clamping part includes a column 41 fixed at the top edge of the lower plate 21 and a ring plate 42 located at the top of the column 41. The bottom of the ring plate 42 is provided with a ring groove, and the top of the column 41 is slidably connected to the inside of the ring groove, so that when the column 41 is used to support the ring plate 42, it will not hinder the reversing drive part from driving the ring plate 42 to rotate. A semicircular groove corresponding to the culture tube 10 is provided on the inner side of the ring plate 42, and an arc groove 43 is provided in the middle of the inner side of the semicircular groove;

[0054] The two ends of the inner side of the arc groove 43 are movably connected with an arc plate 1 44 and an arc plate 2 45, and both ends of the inner side of the arc groove 43 are fixed with a limiting arc bar 49 for limiting the arc plate 1 44 and the arc plate 2 45 at the end. A gear 2 46 driven by a servo motor is rotatably installed in the middle of the inner side of the arc groove 43. The surfaces of the opposite ends of the arc plate 1 44 and the arc plate 2 45 are fixed with an arc rack 1 47 meshing with the gear 2 46, and the inner sides of the opposite ends of the arc plate 1 44 and the arc plate 2 45 are fixed with an arc-shaped clamping block 48. In the embodiment, the radius of the semicircular groove is equal to the outer radius of the culture tube 10, and at the same time, the inner radius of the arc-shaped structure clamping block 48 is equal to the radius of the semicircular groove. By adopting a synchronous telescopic design for the arc plate 1 44 and the arc plate 2 45, it is convenient to fasten and loosen the culture tube 10. Furthermore, the limiting arc strips 49 are respectively arranged at the inner top and bottom of the arc-shaped groove 43, and the height of the clamping block 48 is equal to the distance between the limiting arc strips 49 at the inner top and bottom of the arc-shaped groove 43, which can ensure that the arc plate 1 44 and the arc plate 2 45 can stably telescope.

[0055] The reversing drive unit includes a support plate 410 fixedly sleeved on the outside of the connecting rod 23, a servo motor is fixedly installed on the top of the support plate 410, a gear three 411 is fixedly connected to the end of the output shaft of the servo motor, and an arc-shaped rack two 412 meshing with the gear three 411 is fixedly provided at the position of the outer side of the ring disk 42 corresponding to the support plate 410.

[0056] It should be noted that, in the process of clamping and fixing the culture tube 10, the culture tube 10 is buckled inside the semicircular groove, and then the servo motor is used to drive the gear 2 46 to rotate, and the rotating gear 2 is used to drive the arc rack 1 47 on the arc plate 1 44 and the arc plate 2 45 to move in opposite directions along the arc groove 43, thereby driving one end of the clamping block 48 installed on the arc plate 1 44 and the arc plate 2 45 to extend out of the arc groove 43, completing the clamping of the culture tube 10, so that the axis of the culture tube 10 is always on the circular track surrounded by the axis of the multiple row tubes 8 and the multiple hosting tubes 9;

[0057] When it is necessary to drive the culture tube 10 to switch its position between the row tube 8 and the trustee 9, the servo motor is used to drive the gear three 411 to rotate, and the rotating gear three 411 is used to drive the arc rack two 412 to move, thereby driving the ring disk 42 to rotate a corresponding angle, thereby completing the switching of the position of the culture tube 10 between the row tube 8 and the trustee 9.

[0058] Specifically, Figure 3-Figure 4 and Figure 6As shown, a circulating flow mechanism 5 for promoting the flow of culture fluid is provided at the position corresponding to each pedestal 9 on the upper plate 22, and a culture tube 10 is provided between the correspondingly arranged pedestal 9 and the circulating flow mechanism 5. The culture tube 10 is composed of an outer tube and an inner tube. A connecting column is fixedly provided between the inner side of the outer tube and the outer side of the inner tube. Both ends of the inner tube are of a sinking design compared to the corresponding ends of the outer tube, so as to facilitate the reciprocating flow of algae fluid (culture fluid containing microalgae, the same below) between the inner and outer tubes.

[0059] The circulating flow mechanism 5 includes a limit frame 51 fixed at the bottom of the upper plate 22 at a position corresponding to the trustee 9 and a cylinder 52 fixedly installed at the top of the upper plate 22 at a position corresponding to the trustee 9, wherein the bottom end surface of the limit frame 51 is horizontally coplanar with the upper end surface of the culture tube 10 after docking with the trustee 9, and the limit frame 51 will not block the inner tube, and the telescopic end of the cylinder 52 is fixedly connected with a piston 53 that is adapted to the inner diameter of the inner tube.

[0060] It should be noted that, in the process of cultivating microalgae, the upper end of the culture tube 10 can be limited by the limit frame 51, and then the piston 53 can be pushed into the inner tube through the cylinder 2 52, and the piston 53 can be pushed to perform reciprocating lifting and lowering motion inside the inner tube. During this process, when the piston 53 moves from top to bottom, it will push the algae liquid on the inner side of the inner tube to discharge downward from the inner tube, and then flow back to the inner tube through the annular cavity between the inner tube and the outer tube. When the piston 53 moves from bottom to top, it will push the algae liquid on the inner side of the inner tube to discharge upward from the inner tube, and then flow back to the inner tube through the annular cavity between the inner and outer tubes. This way of algae liquid flow can effectively avoid the light blocking problem caused by the microalgae sticking to the wall, and at the same time, it can also effectively alleviate the shading caused by the microalgae cells themselves.

[0061] Specifically, Figure 3 and Figure 7 As shown, a light source mechanism 6 for providing illumination to the microalgae inside the culture tube 10 is provided between the upper plate 22 and the lower plate 21. The light source mechanism 6 includes a cover frame 62 and a lamp tube 61 installed at an axial position inside the cover frame 62. A column foot is fixedly connected between the cover frame 62 and the lower plate 21. A light guide plate 63 corresponding to the culture tube 10 is fixedly embedded on the outer side of the cover frame 62. The setting of the cover frame 62 can effectively avoid mutual influence between illuminations of different culture areas. A plurality of shielding blocks 65 are equidistantly provided from top to bottom on the inner side of the light guide plate 63. The shielding blocks 65 can be used to divide the light receiving area of ​​the culture tube 10 into a plurality of light and dark alternating areas, so that the flowing algae liquid can repeatedly circulate alternately between the light and dark areas to form a flashing effect, thereby promoting the photosynthesis of the microalgae.

[0062] A U-shaped frame 64 is fixedly provided on the inner side of the cover frame 62 at a position corresponding to the light guide plate 63, and a filter 68 is fixedly embedded in the middle of the U-shaped frame 64 at a position corresponding to the light transmission area on the light guide plate 63. The filter 68 is composed of red, green and blue three-color filter sheets arranged in sequence from top to bottom, and electric push rods 66 are fixedly installed on both sides of the U-shaped frame 64 at a position corresponding to each filter sheet. The telescopic end of each electric push rod 66 is fixedly connected with an L-shaped shielding plate 67, and the electric push rod 66 can be used to push the corresponding L-shaped shielding plate 67 to partially or completely block the filter sheet in the area, thereby adjusting the exposure amount of different colors of light.

[0063] It should be noted that, in the process of providing illumination to the microalgae inside the culture tube 10, the light emitted by the lamp tube 61 is filtered by the filter 68, and the light passing through the filter 68 is guided to the culture tube 10 by the light guide plate 63, so that the microalgae inside the culture tube 10 undergo photosynthesis. In this process, the corresponding L-shaped shielding plate 67 can be pushed in advance by the electric push rod 66 to partially shield the filter sheet in the area, so that the shielding amount of the three-color filter sheet of the filter 68 on the light-transmitting area of ​​each culture station is consistent (the carbon dioxide supply is inconsistent), and the optical density method is used irregularly during the culture period to measure the biomass change in the microalgae culture process, and then the light-transmitting surface on each filter sheet is adjusted according to the measurement results;

[0064] Similarly, in the process of adjusting the size of the light-transmitting surface, the blocking amount of the three-color filter single piece of the filter 68 on the light-transmitting area of ​​each culture station can be made inconsistent (the carbon dioxide supply is sufficient), but the blocking amount of the filter single piece in each light-transmitting area of ​​each culture station is the same;

[0065] The above is the optimal culture condition determined when the photobioreactor is used for laboratory microalgae culture. When the photobioreactor is put into production, each culture station needs to be cultured under the optimal culture condition.

[0066] Specifically, Figure 3-Figure 8 As shown, a rotating mechanism 3 for driving the culture tube 10 to continuously rotate is provided between the base frame 1 and the bracket 2. The rotating mechanism 3 is composed of a rotating driving part and a docking clamping part. The rotating driving part includes a driving motor installed at the inner side of the base frame 1 at the position corresponding to the lamp tube 61. The output shaft end of the driving motor is fixedly connected with a gear 31. The outer side of each hosting tube 9 is fixedly sleeved with a gear ring 32 meshing with the gear 31. The hosting tube 9 is rotatably installed on the lower plate 21 through a bearing, and the outer side of each hosting tube 9 located at the upper and lower end surfaces of the lower plate 21 is fixedly sleeved with a limiting ring plate 14, wherein a rotating installation structure can be set between the hosting tube 9 and the lower plate 21, so that during the rotation of the gear 31, each hosting tube 9 can be driven to rotate synchronously;

[0067] The docking clamping part includes a cylinder 37 fixedly installed at the bottom of the cover frame 62 and a ring block 13 fixedly sleeved on the outer bottom end of the culture tube 10. The telescopic end of the cylinder 37 is fixedly connected to the lifting plate 33, and the column foot at the bottom end of the cover frame 62 movably penetrates the lifting plate 33. A clamping hole 36 is penetrated on the ring block 13. A flip plate 12 driven by a servo motor is rotatably installed at the position of the inner side of the culture tube 10 corresponding to the ring block 13. The flip plate 12 can be used to block the bottom port of the culture tube 10, so that the culture tube 10 will not leak during the process of switching positions.

[0068] The docking clamping portion also includes a ring 34 movably sleeved on the outside of the hosting 9, and a T-shaped ring groove is opened on the outside of the ring 34. A T-shaped clamping plate slidably installed in the T-shaped ring groove is fixedly provided at the position of the outer side of the lifting plate 33 corresponding to the ring 34. The setting of the T-shaped ring groove and the T-shaped clamping plate can prevent the ring 34 from being separated during the rotation of the relative lifting plate 33. A clamping cylinder 35 is fixedly provided at the position of the clamping hole 36 on the ring block 13 at the top of the ring 34. A clamping column that penetrates the ring is movably sleeved inside the clamping cylinder 35, and the bottom end of the clamping column is fixedly connected to the limiting ring plate 14 located above the lower plate 21 on the outside of the corresponding hosting 9. Among them, after the top end of the clamping cylinder 35 is inserted into the clamping hole 36 at the corresponding position, the top end of the clamping column still remains inserted into the state of the clamping cylinder 35, ensuring that the hosting 9 can drive the culture tube 10 to rotate synchronously during the rotation, so that the microalgae in each area of ​​the culture tube 10 can be fully exposed to the light source.

[0069] It should be noted that, in the process of driving the culture tube 10 to rotate so that the microalgae in each area inside can be fully exposed to the light source, the lifting plate 33 is pushed downward by the cylinder 37, so that the top of the cartridge 35 is lower than the horizontal plane where the bottom end surface of the ring block 13 is located. When the culture tube 10 filled with culture solution and target microalgae species rotates with the ring disk 42 and switches to the top of the trustee 9, the cylinder 37 is controlled to drive the lifting plate 33 to rise, so that the cartridge 35 is plugged into the card hole 36 on the ring block 13. At this time, the gear 31 is driven by the driving motor to rotate, and the trustee 9 with the gear ring 32 is driven by the rotating gear 31 to rotate, thereby driving the culture tube 10 to rotate synchronously. In this process, when the culture tube 10 is switched to the top of the trustee 9, the docking area of ​​the trustee 9 and the culture tube 10 is sealed by the sealing ring. At this time, the servo motor is used to drive the flip plate 12 to rotate to release the blocking state of the bottom opening of the culture tube 10, wherein the sealing ring can be directly fixed on the upper end surface of the trustee 9.

[0070] Specifically, Figure 4-Figure 6 and Figure 9-11As shown, each tube 9 is provided with an air supply mechanism 7 on the inner side, and the air supply mechanism 7 includes a plug 71 fixed on the inner side of the tube 9, and an air supply pipe 72 fixed on the base frame 1 is rotatably installed at the bottom end of the plug 71, and a one-way valve is installed on the air supply pipe 72 to prevent the algae liquid from flowing back into the air supply pipe 72, and an annular groove is provided on the inner side of the plug 71, and a diffusion disk 73 and a positioning member 74 for fixing the diffusion disk 73 are movably embedded in the annular groove, wherein an arc-shaped protrusion of a V-shaped structure is provided at the center position of the bottom end surface of the diffusion disk 73 to guide the bubbles generated in the process of supplying carbon dioxide gas to diffuse in an annular shape to the pore area, and the pore area is used to squeeze the bubbles to release carbon dioxide to fully contact with the microalgae, and at the same time, small bubbles are formed to escape to the upper end of the culture tube 10, and the small bubbles are further squeezed to release carbon dioxide under the pressure of repeated flow of algae liquid, so as to further improve the utilization rate of carbon dioxide;

[0071] The positioning member 74 includes a column 741 fixed on the inner side of the annular groove and a through hole penetrating the diffusion plate 73, and the column 741 is penetrated in the corresponding through hole, a through groove 744 is penetrated on the outer side of the column 741, a square groove connected to the through groove 744 is formed on the top of the column 741, a square column 743 is movably penetrated in the square groove, and a circular plate 742 and a push block 748 are fixedly connected at both ends of the square column 743 respectively;

[0072] Two trapezoidal blocks 745 and two ear blocks 746 fixedly arranged at the middle of the inner side of the through groove 744 are movably sleeved inside the through groove 744. Springs 747 are fixedly connected between the opposite sides of the two trapezoidal blocks 745 and the ear blocks 746. When the springs 747 are in a natural state, the bottom ends of the opposite sides of the two trapezoidal blocks 745 are in contact. At this time, the two trapezoidal blocks 745 are just completely received in the through groove 744, so as not to hinder the diffusion plate 73 from being buckled into the annular groove. This state is assumed to be In the initial state, V-grooves 749 are provided on both sides of the push block 748, and an elastic clamp 7410 is provided at the position of the V-groove 749 on the inner side of the through groove 744, wherein the elastic clamp 7410 is composed of a connecting spring, a plug column and a V-block fixedly connected to the plug column, and a column hole is provided on the inner side of the through groove 744 at the position corresponding to the V-groove 749, one end of the plug column is inserted into the column hole, and the connecting spring is sleeved on the outside of the plug column, and the two ends of the connecting spring are respectively fixedly connected to the V-block and the inner wall of the through groove 744.

[0073] It should be noted that during the installation of the diffusion disk 73, after the column rod 741 is inserted into the positioning hole on the diffusion disk 73, the circular plate 742 is pressed downward, and the square column 743 is used to push the push block 748 downward, so that the two trapezoidal blocks 745 move in opposite directions under the push of the push block 748, and the spring 747 at the corresponding position is stretched. After the downward moving push block 748 contacts the V-block on the elastic clamp 7410, the circular plate 742 is continued to be pressed downward to allow the plug column to shrink into the column hole and compress the connecting spring. When the V-groove 749 on the surface of the push block 748 corresponds to the V-block, the V-block will gradually be inserted into the corresponding V-groove 749 under the action of the restoring force of the connecting spring, thereby limiting the two trapezoidal blocks 745 in the current state and completing the installation and fixation of the diffusion disk 73.

[0074] In the above technical scheme, the servo motor mentioned uses a servo driver of model JSMA-PUC02D; the servo motor mentioned uses a servo driver of model JSDL2-10A1; the cylinder 1 37 and cylinder 2 52 mentioned use single-acting cylinders of model DSA25N200; the electric push rod 66 mentioned uses an electric push rod of model HB-DJ801; the drive motor mentioned uses a micro motor of model R380.

[0075] A method for controlling the above-mentioned photobioreactor for culturing microalgae comprises the following steps:

[0076] S1. Establishing a photobioreactor: injecting culture solution and target microalgae species into the culture tube 10, placing the culture tube 10 above the hosting tube 9, and adjusting the light intensity and carbon dioxide supply rate;

[0077] S2, start the culture: use the driving motor to drive the gear 1 31 to rotate, so that the culture tube 10 rotates under the drive of the gear 1 31, and at the same time, use the cylinder 2 52 to push the piston into the inner tube, and reciprocate and lift the inner tube, so that the algae liquid flows back and forth between the inner tube and the outer tube;

[0078] S3. Regulation of culture conditions: The optical density method (based on the linear relationship between the absorbance of microalgae at a specific wavelength and the cell density, by measuring the optical density of microalgae, the biomass, dry mass of biomass and cell density of algae liquid can be more accurately calculated) is used to measure the biomass change during the microalgae culture process, and the supply surface of different colors of light and the carbon dioxide supply rate are adjusted according to the measured values;

[0079] S4. Re-cultivation: After the initial cultivation is completed, the bottom opening of the culture tube 10 is blocked by the flip plate 12, and the tube clamping part is driven by the reversing drive part to switch the culture tube from the tube 9 to the discharge tube 8, the algae liquid is discharged, and then new culture liquid is injected, and the initial algae liquid trapped inside the tube 9 is used as the algae species for re-cultivation.

[0080] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A photobioreactor for culturing microalgae, characterized in that: The invention comprises a base frame (1), a bracket (2) is fixedly mounted on the top of the base frame (1), the bracket (2) is composed of a lower plate (21), an upper plate (22) and a connecting rod (23) fixedly connecting the upper plate (22) and the lower plate (21), the lower plate (21) is penetrated by a plurality of pipes (8) and tubes (9) evenly distributed in a ring shape, and the pipes (8) and tubes (9) are alternately distributed, and a splash-proof plate frame (11) is fixedly mounted on the inner side of the base frame (1) at a position corresponding to each pipe (8); A circulation flow mechanism (5) for promoting the flow of culture fluid is provided at a position corresponding to each trustee (9) on the upper plate (22), and a culture tube (10) is provided between the corresponding trustee (9) and the circulation flow mechanism (5), the culture tube (10) being composed of an outer tube and an inner tube, and a connecting column is fixedly provided between the inner side of the outer tube and the outer side of the inner tube; The circulation mechanism (5) comprises a limit frame (51) fixed at the bottom of the upper plate (22) at a position corresponding to the trustee (9) and a second cylinder (52) fixedly installed at the top of the upper plate (22) at a position corresponding to the trustee (9), wherein the telescopic end of the second cylinder (52) is fixedly connected to a piston (53) adapted to the inner diameter of the inner tube; A clamping and reversing mechanism (4) for driving the culture tube (10) to switch positions and a light source mechanism (6) for providing light to the microalgae inside the culture tube (10) are provided between the upper plate (22) and the lower plate (21); the clamping and reversing mechanism (4) is composed of a reversing driving part and a tube clamping part; The light source mechanism (6) comprises a cover frame (62) and a lamp tube (61) mounted at an axial position inside the cover frame (62); a column foot is fixedly connected between the cover frame (62) and the lower plate (21); a light guide plate (63) corresponding to the culture tube (10) is fixedly embedded on the outside of the cover frame (62); and a plurality of shielding blocks (65) are equidistantly arranged from top to bottom on the inside of the light guide plate (63); A U-shaped frame (64) is fixedly provided on the inner side of the cover frame (62) at a position corresponding to the light guide plate (63); a filter (68) is fixedly embedded in the middle of the U-shaped frame (64) at a position corresponding to the light transmission area on the light guide plate (63); the filter (68) is composed of red, green and blue three-color filter sheets arranged in sequence from top to bottom; electric push rods (66) are fixedly installed on both sides of the U-shaped frame (64) at a position corresponding to each filter sheet; and an L-shaped shielding plate (67) is fixedly connected to the telescopic end of each electric push rod (66); A rotating mechanism (3) for driving the culture tube (10) to continuously rotate is provided between the base frame (1) and the bracket (2); the rotating mechanism (3) is composed of a rotating driving part and a docking clamping part.

2. A photobioreactor for culturing microalgae according to claim 1, characterized in that: The tube clamping portion comprises a column (41) fixed at the top edge of the lower plate (21) and a ring plate (42) located at the top of the column (41); a ring groove is provided at the bottom of the ring plate (42), and the top of the column (41) is slidably connected to the inside of the ring groove; a semicircular groove corresponding to the culture tube (10) is provided on the inner side of the ring plate (42), and an arc-shaped groove (43) is provided in the middle of the inner side of the semicircular groove; The two ends of the inner side of the arc-shaped groove (43) are respectively movably connected with an arc plate 1 (44) and an arc plate 2 (45), and both ends of the inner side of the arc-shaped groove (43) are fixedly provided with limiting arc bars (49) for limiting the arc plate 1 (44) and the arc plate 2 (45) at the ends thereof, and a gear 2 (46) driven to rotate by a servo motor is rotatably installed in the middle part of the inner side of the arc-shaped groove (43), and an arc rack 1 (47) meshing with the gear 2 (46) is fixedly provided on the opposite end surfaces of the arc plate 1 (44) and the arc plate 2 (45), and a clamping block (48) is fixedly provided on the inner side of the opposite ends of the arc plate 1 (44) and the arc plate 2 (45).

3. A photobioreactor for culturing microalgae according to claim 2, characterized in that: The reversing drive unit comprises a support plate (410) fixedly sleeved on the outside of the connecting rod (23), a servo motor fixedly mounted on the top of the support plate (410), a gear three (411) fixedly connected to the end of the output shaft of the servo motor, and an arc-shaped rack two (412) meshing with the gear three (411) fixedly provided at a position on the outside of the ring disk (42) corresponding to the support plate (410).

4. The photobioreactor for culturing microalgae according to claim 1, characterized in that: The rotation drive unit comprises a drive motor mounted on the inner side of the base frame (1) at a position corresponding to the position of the lamp tube (61); the end of the output shaft of the drive motor is fixedly connected to a gear one (31); a gear ring (32) meshing with the gear one (31) is fixedly sleeved on the outer side of each tube (9); the tube (9) is rotatably mounted on the lower plate (21) via a bearing; and a limiting ring plate (14) is fixedly sleeved on the outer side of each tube (9) at a position located on the upper and lower end surfaces of the lower plate (21).

5. The photobioreactor for culturing microalgae according to claim 1, characterized in that: The docking clamping portion comprises a cylinder 1 (37) fixedly mounted on the bottom of the cover frame (62) and a ring block (13) fixedly sleeved on the bottom end of the outer side of the culture tube (10); the telescopic end of the cylinder 1 (37) is fixedly connected to the lifting plate (33); the column foot at the bottom end of the cover frame (62) movably penetrates the lifting plate (33); a clamping hole (36) is penetrated on the ring block (13); and a turning plate (12) driven by a servo motor is rotatably mounted at a position on the inner side of the culture tube (10) corresponding to the ring block (13); The docking clamping portion also includes a collar (34) movably sleeved on the outside of the trustee (9), a T-shaped ring groove is provided on the outside of the collar (34), a T-shaped clamping plate slidably mounted inside the T-shaped ring groove is fixedly provided at a position corresponding to the collar (34) on the outside of the lifting plate (33), a clamping cylinder (35) is fixedly provided at a position corresponding to the clamping hole (36) on the ring block (13) at the top of the collar (34), a clamping column that passes through the collar is movably sleeved inside the clamping cylinder (35), and the bottom end of the clamping column is fixedly connected to a limiting ring plate (14) located above the lower plate (21) on the outside of the corresponding trustee (9).

6. The photobioreactor for culturing microalgae according to claim 1, characterized in that: An air supply mechanism (7) is provided on the inner side of each of the tubes (9), the air supply mechanism (7) comprising a plug (71) fixedly arranged on the inner side of the tube (9), an air supply pipe (72) fixed on the base frame (1) being rotatably mounted on the bottom end of the plug (71), and an annular groove is provided on the inner side of the plug (71), a diffusion disc (73) and a positioning member (74) for fixing the diffusion disc (73) being movably mounted in the annular groove.

7. A photobioreactor for culturing microalgae according to claim 6, characterized in that: The positioning member (74) comprises a column (741) fixed on the inner side of the annular embedding groove and a through hole penetrating the diffusion plate (73), wherein the column (741) is penetrated in the corresponding through hole, a through groove (744) is penetrated on the outer side of the column (741), a square groove connected to the through groove (744) is formed on the top of the column (741), a square column (743) is movably penetrated in the square groove, and a circular plate (742) and a push block (748) are fixedly connected at both ends of the square column (743) respectively; The through groove (744) is movably sleeved with two trapezoidal blocks (745) and two ear blocks (746) fixedly arranged at the middle of the inner side of the through groove (744); springs (747) are fixedly connected between the opposite sides of the two trapezoidal blocks (745) and the ear blocks (746); V-shaped grooves (749) are provided on both sides of the push block (748); and elastic clamps (7410) are provided at positions on the inner side of the through groove (744) corresponding to the V-shaped grooves (749).

8. A method for controlling a photobioreactor for culturing microalgae, for controlling the photobioreactor for culturing microalgae according to any one of claims 1 to 7, characterized in that: The specific steps include the following: S1. Establishing a photobioreactor: injecting culture solution and target microalgae species into a culture tube (10), placing the culture tube (10) above the hosting tube (9), and adjusting the light intensity and carbon dioxide supply rate; S2, start the culture: use the drive motor to drive the gear 1 (31) to rotate, so that the culture tube (10) rotates under the drive of the gear 1 (31), and at the same time, use the cylinder 2 (52) to push the piston into the inner tube, and reciprocate and lift the piston inside the inner tube, so that the algae liquid flows back and forth between the inner tube and the outer tube; S3. Cultivation condition regulation: The optical density method is used to measure the biomass changes during the microalgae cultivation process, and the supply surface of different color lights and the carbon dioxide supply rate are adjusted according to the measured values; S4. Re-cultivation: After the initial cultivation is completed, the bottom opening of the culture tube (10) is blocked by the flip plate (12), and the tube clamping part is driven by the reversing drive part to switch the culture tube from the tube (9) to the discharge tube (8), discharge the algae liquid, and then inject new culture liquid, and use the initial culture algae liquid trapped inside the tube (9) as the algae seed for re-cultivation.

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