Novel microalgae industrial production photobioreactor system

Abstract

The invention belongs to special industrial production equipment for culturing microalgae by adopting artificial light, and particularly relates to a novel microalgae industrial production photobioreactor system, which comprises a reaction tank, a photobioreactor system, a light source, a light source and a control system, and is characterized in that the reaction tank is used for placing algae liquid and the photobioreactor system; an algae liquid extraction and ultraviolet light disinfection system; the first LED lamp tube part and the second LED lamp tube part act on a reaction system in the reaction tank; the algae liquid extraction and ultraviolet light disinfection system designed according to the algae liquid absorbance value control range is composed of a submersible pump, a submersible pump output pipeline, a stainless steel overflowing pipe, an ultraviolet light lamp and a tap water pipeline for cleaning, and the algae liquid absorbance value control range is 0.2-0.4 during algae liquid extraction; in a matched algae liquid extraction and ultraviolet light disinfection system, the power range of an ultraviolet lamp is 10W-30W, the light wave range is 250nm-260nm, the length range of an ultraviolet lamp tube is 220mm-580mm, the ultraviolet lamp is placed in a stainless steel overflowing pipe, two ends of the stainless steel overflowing pipe are sealed, an algae liquid input port and an algae liquid output port are formed in the top of the stainless steel overflowing pipe, the diameter (outer diameter) range of the stainless steel overflowing pipe is 50mm-65mm, the length range of the stainless steel overflowing pipe is 260mm-620mm, and the length range of the stainless steel overflowing pipe is 20mm-20mm. And the flow control range of the stainless steel overflowing pipe is 0.3-3.5 tons / hour. According to the method, the problem of matching of the algae liquid absorbance value with various parameters of the ultraviolet light sterilizer in the ultraviolet light sterilization technical link used in microalgae industrial production is solved, so that the damage degree of active nutrient substances in the microalgae industrial production process is reduced to the minimum, and meanwhile, the food safety standard can be met.

Description

Technical Field

[0001] The invention belongs to special equipment for industrial production of microalgae cultivated by artificial light, and in particular refers to a novel photobioreactor system for industrial production of microalgae. Technical Background

[0002] Traditional microalgae farming mostly uses paddy fields or ponds to rely on sunlight for outdoor farming, among which Spirulina and Chlorella are representative. Due to poor outdoor sanitary conditions, the collected microalgae need to be sterilized at high temperature before they can be eaten. However, the active substances contained in the microalgae after high-temperature sterilization are lost in large quantities, resulting in a significant reduction in nutritional effect. Therefore, the new production method uses artificial light to replace outdoor sunlight with photobiotechnology to cultivate microalgae indoors in a clean manner. The collected microalgae are sterilized with ozone water or ultraviolet light at room temperature to retain the activity of the microalgae, which has become the first choice for the current industry development. For example, patent ZL2022 2 3113631.3, patent ZL202221309132.9, etc. However, ozone or ultraviolet disinfection still has a certain degree of damage to the active substances of microalgae. Therefore, how to disinfect the microalgae with the most reasonable disinfection time and disinfection dose under the premise of meeting the relevant national standards for algae food safety, while retaining the active substances of the microalgae to the maximum extent, is the key to the development of the microalgae industry. Therefore, the following problems still exist in the use of photobiotechnology to cultivate microalgae indoors:

[0003] 1. Ozone water disinfection causes a certain degree of air pollution. At the same time, there are many human factors in the operation process of ozone water disinfection, and it is impossible to form a unified and standardized controllable process flow, resulting in a large difference in the loss of active nutrients of microalgae after each batch of disinfection. At the same time, the number of microalgae colonies after each batch of disinfection also varies greatly.

[0004] 2. Under the premise of meeting relevant food safety standards, there is a lack of research on how to maximize the retention of microalgae activity through reasonable disinfection technical parameter control, and a lack of research on how to match different algae liquid absorbance values ​​(representing algae liquid concentration, different algae liquid flow volume and other parameters) with ultraviolet light. The importance of parameter matching lies in: excessive ultraviolet light can cause changes in the protein structure of microalgae, resulting in loss of protein function or inactivation. Therefore, the appropriate matching of algae liquid absorbance and ultraviolet light intensity is a key factor.

[0005] 3. There is a lack of research on the more preferred artificial spectrum for the cultivation of various microalgae such as diatoms, cyanobacteria, and green algae.

[0006] 4. The light source pipeline in the photobiological reaction system works in the algae liquid for a long time, the microalgae on the surface of the lamp tube are seriously adhered to the wall, the light is blocked, the light intensity is greatly reduced, and the microalgae yield is reduced.

[0007] The above are the bottleneck problems of microalgae production technology, which determine the content of active nutrients in microalgae products and the nutritional effects of microalgae. Since 2020, the inventor team has been engaged in the research on industrial production of clean indoor cultivation of microalgae using artificial light technology for a long time. Microalgae photobiotechnology cultivation and industrial production pilot and pilot bases have been set up in Beihai Marine Industrial Park, Guangxi and Guangxi Academy of Sciences. By establishing relevant mathematical models and a large number of experiments, the reasonable range data of how the absorbance value of algae liquid in the ultraviolet disinfection process of microalgae matches the various technical parameters of ultraviolet disinfection have been obtained. At the same time, for the commonly used varieties of diatoms, cyanobacteria, and green algae such as Chaetoceros, golden algae, Spirulina, Chlorella, etc., a more preferred artificial light spectrum has been studied, which has laid a bioengineering foundation for the industrial production of microalgae. Summary of the invention

[0008] The present invention provides a novel photobioreactor system for industrial production of microalgae, comprising an LED lamp tube acting on a reaction system in a reaction pool, and an algae liquid extraction and ultraviolet light disinfection system designed according to the algae liquid absorbance value within a certain numerical range, so as to achieve the purpose of minimizing damage, maximizing yield, and retaining the most active substances during the microalgae cultivation and disinfection process.

[0009] The overall technical concept of the present invention is:

[0010] The novel photobioreactor system for industrialized production of microalgae includes a reaction tank: for placing algae liquid and a photobioreactor system; an algae liquid extraction and ultraviolet light disinfection system; a first LED lamp tube part and a second LED lamp tube part acting on the reaction system in the reaction tank; the algae liquid extraction and ultraviolet light disinfection system designed according to the control range of the algae liquid absorbance value is composed of a submersible pump, a submersible pump output pipeline, a stainless steel flow pipe, an ultraviolet light lamp and a tap water pipeline for cleaning. When the algae liquid is extracted, the control range of the algae liquid absorbance value is 0.2-0.4. The power range of the UV lamp in the matching algae liquid extraction and UV disinfection system is 10W-30W, the light wave range is 250nm-260nm, and the length range of the UV lamp is 220mm-580mm. The UV lamp is placed in a stainless steel flow tube which is sealed at both ends and has an algae liquid inlet and an algae liquid outlet on the top. The diameter (outer diameter) of the stainless steel flow tube ranges from 50mm to 65mm, and the length ranges from 260mm to 620mm. The flow control range of the stainless steel flow tube is 0.3-3.5 tons / hour.

[0011] The specific technical concept of the present invention also includes:

[0012] In order to form uniform and effective lighting in the pool body, the preferred technical implementation method is that multiple groups of LED special spectrum light strips acting on the reaction system are placed in a transparent tube to form a first LED light tube part and a second LED light tube part composed of multiple groups of light tubes, and arranged vertically. One side of the water circulation baffle in the middle of the reaction pool is the first light tube part, the light tube is a straight tube, and the openings at both ends of the pipe pass through the opposite sides of the reaction pool wall respectively, and one end is equipped with a cooling fan; the other side of the water circulation baffle is the second light tube part and the water wheel, the second light tube part is a U-shaped tube, the two ends of the pipe are opened, and the two ends of the U-shaped tube pass through the same side of the reaction pool wall, and one end is equipped with a cooling fan; the first light tube part and the second light tube part are respectively connected to the bottom of the reaction pool by light tube fixing devices.

[0013] In order to effectively promote the photosynthesis of various microalgae such as diatoms, blue algae, and green algae, the more preferred technical means is that the light source of the LED special spectrum light strip is a combination of two continuous spectrum light sources:

[0014] (1) The peak wavelength is 450±2nm, the main wavelength is 487±2nm, and the continuous spectrum range is 400nm-720nm.

[0015] (2) The peak wavelength is 619±2nm, the main wavelength is 587±2nm, and the continuous spectrum range is 400nm-800nm.

[0016] The essential features and technical advances achieved by the present invention are:

[0017] 1. The reasonable absorbance value range for microalgae disinfection with ultraviolet light has been clarified. Since microalgae can block ultraviolet light, the illumination of microalgae in the near light may be too high, and the activity of microalgae may be damaged. However, the sterilization effect on microalgae in the far light is poor and cannot meet the national food safety standards. Therefore, when using ultraviolet light to disinfect microalgae, the reasonable absorbance value range must be determined first. The principle of determination is to minimize the degree of damage to the activity of microalgae in the near light, and the number of microalgae colonies in the far light must meet the national food safety standards.

[0018] 2. The various parameters of the ultraviolet disinfection system that match the absorbance value range of microalgae when extracting algae liquid are further clarified, including algae liquid flow rate, ultraviolet lamp power, light wave range, stainless steel flow tube length and diameter range, forming a complete technical parameter system for microalgae concentration requirements and ultraviolet disinfection, laying the foundation for the industrial production of microalgae.

[0019] 3. Two more preferred spectral combinations for microalgae cultivation have been identified. These are data obtained based on a large number of experiments on a variety of cyanobacteria, green algae, and diatoms. Different microalgae have different absorption peaks and sub-absorption peaks for light waves. By establishing relevant mathematical models and conducting a large number of experiments, we can study a more preferred artificial spectral combination suitable for most microalgae cultivation, laying the foundation for industrial production.

[0020] 4. The lamps in the reaction pool are arranged longitudinally and spaced apart. The extension direction of the lamps is consistent with the direction of water flow, which reduces flow resistance, speeds up water flow, increases the chances of microalgae being exposed to light, and reduces the adhesion of microalgae to the pipe surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the photobioreactor system structure for industrial production of new microalgae.

[0022] Figure 2 This is a schematic diagram of the structure of the algae liquid extraction and ultraviolet disinfection system.

[0023] The reference numerals in the accompanying drawings are as follows:

[0024] 1. Reaction tank. 2. Water circulation baffle. 3. First LED lamp tube part.

[0025] 4. LED special spectrum light strip. 5. The second LED light tube part.

[0026] 6. Algae liquid extraction and ultraviolet disinfection system. 7. Lamp fixture.

[0027] 8. Submersible pump. 9. Submersible pump output pipeline. 10. Submersible pump output pipeline valve.

[0028] 11. Cleaning water pipeline. 12. Water pipeline valve. 13. Algae liquid input port.

[0029] 14. Algae liquid outlet. 15. Stainless steel flow pipe. 16. Ultraviolet lamp. 17. Algae liquid outlet pipe. 18. Algae-liquid separator. 19. Cooling fan. 20. Cooling fan. 21. Water wheel. 22. Hole reserved for lamp tube.

[0030] 23. Power cord. 24. Wastewater discharge pipe.

[0031] The accompanying drawings show embodiments of the present invention. The embodiments of the present invention are further described below in conjunction with the accompanying drawings, but should not be construed as limiting the present invention. The protection scope of the present invention shall be based on the contents recorded in the claims. Any replacement of equivalent technical means made according to the specification shall not depart from the protection scope of the present invention.

[0032] The overall structure of this embodiment is shown in the figure: it includes a reaction pool (1): for placing algae liquid and a photobioreactor system; an algae liquid extraction and ultraviolet light disinfection system (6); a first LED lamp tube part (3) and a second LED lamp tube part (5) acting on the reaction system in the reaction pool (1); the algae liquid extraction and ultraviolet light disinfection system (6) designed according to the control range of the algae liquid absorbance value is composed of a submersible pump (8), a submersible pump output pipeline (9), a stainless steel flow pipe (15), an ultraviolet lamp (16) and a tap water pipeline (11) for cleaning. When the algae liquid is extracted, the control range of the algae liquid absorbance value is 0.2-0.4. In the matching algae liquid extraction and ultraviolet disinfection system (6), the ultraviolet lamp (16) has a power range of 10W-30W, a light wave range of 250nm-260nm, and a length range of 220mm-580mm. The ultraviolet lamp (16) is placed in a stainless steel flow tube (15) which is sealed at both ends and has an algae liquid inlet (13) and an algae liquid outlet (14) on the top. The diameter (outer diameter) of the stainless steel flow tube (15) ranges from 50mm to 65mm, and the length ranges from 260mm to 620mm. The flow control range of the stainless steel flow tube (15) is 0.3-3.5 tons / hour.

[0033] A plurality of groups of LED special spectrum light strips (4) acting on the reaction system are placed in a transparent tube to form a first LED light tube part (3) and a second LED light tube part (5) composed of a plurality of light tubes, and arranged longitudinally. One side of a water circulation baffle (2) in the middle of the reaction pool (1) is the first light tube part (3), the light tube is a straight tube, and openings at both ends of the tube pass through two opposite sides of the wall of the reaction pool (1), one end of which is equipped with a cooling fan (19); the other side of the water circulation baffle (2) is the second light tube part (5) and a water wheel (21), the second light tube part (5) is a U-shaped tube, and openings at both ends of the tube pass through the same side of the wall of the reaction pool (1), and one end of which is equipped with a cooling fan (20); the first light tube part (3) and the second light tube part (5) are respectively connected to the bottom of the reaction pool (1) by light tube fixing devices (7), and the reaction pool (1) is square or oval.

[0034] The light source of the LED special spectrum light strip (4) is a combination of two continuous spectrum light sources:

[0035] (1) The peak wavelength is 450±2nm, the main wavelength is 487±2nm, and the continuous spectrum range is 400nm-720nm.

[0036] (2) The peak wavelength is 619±2nm, the main wavelength is 587±2nm, and the continuous spectrum range is 400nm-800nm.

[0037] This embodiment achieves industrialized production of microalgae by:

[0038] Algae species are placed in the reaction pool (1) and purified water or well water, as well as baking soda, nitrogen, phosphorus and potassium nutrient solution, etc. are injected to form algae liquid. The first LED lamp tube part (3) and the second LED lamp tube part (5) are turned on for lighting, and the water wheel (21) is started to stir the water flow so that the algae liquid can fully enjoy the light and accelerate the growth rate. When the absorbance value of the algae liquid tested by the visible spectrophotometer reaches 0.2-0.4, the submersible pump output pipeline valve (10) is opened, the submersible pump (8) is started, and the algae liquid is pumped into the non- The stainless steel flow pipe (15) is disinfected by an ultraviolet lamp (16). The disinfected algae liquid enters the algae liquid separator (18) through the algae liquid outlet (14) and the algae liquid outlet pipe (17) to form algae mud, which is then packaged into small pieces as needed and stored frozen. The wastewater generated when the algae and liquid are separated is discharged through the wastewater discharge pipe (24). After the algae extraction work is completed, the submersible pump (8) is turned off, the tap water valve (12) is opened, and the algae liquid extraction and ultraviolet disinfection system (6) and the algae liquid separator (18) are reversely flushed.

Claims

1. A novel photobioreactor system for industrial production of microalgae, comprising a reaction pool (1); a system for placing algae liquid and a photobioreactor system; an algae liquid extraction and ultraviolet disinfection system (6); a first LED lamp tube part (3) and a second LED lamp tube part (5) acting on the reaction system in the reaction pool (1); characterized in that The algae liquid extraction and ultraviolet disinfection system (6) designed according to the control range of the absorbance value of the algae liquid is composed of a submersible pump (8), a submersible pump output pipeline (10), a stainless steel flow pipe (15), an ultraviolet lamp (16) and a tap water pipeline (11) for cleaning. When the algae liquid is extracted, the control range of the absorbance value of the algae liquid is 0.2-0.

4. The power range of the ultraviolet lamp (16) in the matching algae liquid extraction and ultraviolet disinfection system (6) is 10W-30W, and the light wave The range is 250nm-260nm, the length of the ultraviolet lamp tube is 220mm-580mm, the ultraviolet lamp (16) is placed in a stainless steel flow tube (15) which is sealed at both ends and has an algae liquid input port (13) and an algae liquid output port (14) on the top. The diameter (outer diameter) of the stainless steel flow tube (15) is 50mm-65mm, the length is 260mm-620mm, and the flow control range of the stainless steel flow tube (15) is 0.3-3.5 tons / hour.

2. The novel microalgae industrial production photobioreactor system according to claim 1 is characterized in that The plurality of groups of LED special spectrum light strips (4) acting on the reaction system are placed in a transparent tube to form a first LED light tube part (3) and a second LED light tube part (5) composed of a plurality of light tubes, and arranged longitudinally. One side of the water circulation baffle (2) in the middle of the reaction pool (1) is the first light tube part (3). The light tube is a straight tube. The openings at both ends of the tube pass through the two opposite sides of the wall of the reaction pool (1), and one end is equipped with a cooling fan (19). The other side of the water circulation baffle (2) is the second light tube part (5) and a water wheel (21). The second light tube part (5) is a U-shaped tube. The openings at both ends of the tube pass through the same side of the wall of the reaction pool (1), and one end is equipped with a cooling fan (20). The first light tube part (3) and the second light tube part (5) are connected to the bottom of the reaction pool (1) by light tube fixing devices (7) respectively. The reaction pool (1) is square or elliptical.

3. The novel microalgae industrial production photobioreactor system according to claim 1 is characterized in that The light sources of the LED special spectrum light strip (4) are respectively a combination of two continuous spectrum light sources: (1) The peak wavelength is 450±2nm, the main wavelength is 487±2nm, and the continuous spectrum range is 400nm-720nm.

4. (2) The peak wavelength is 619±2nm, the dominant wavelength is 587±2nm, and the continuous spectrum range is 400nm-800nm.

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