A high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin and its application

Abstract

The present invention relates to a high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin and its application, belonging to the field of dairy processing and equipment manufacturing. It includes a liquid material feeding system, an air pressure control system, an electrostatic spray drying system and an electromagnetic adsorption system, and also includes a waste gas recovery system. An appropriate amount of inorganic iron solution is added to the lactoferrin liquid, and after uniform dispersion, the liquid is atomized into charged droplets by nitrogen propulsion under low flow rate and high voltage conditions. Under the action of the electric field, the iron ions in the liquid are pushed to the surface of the droplets; at the same time, hot air is drained in the drying chamber, and heat exchange is carried out with an extremely high specific surface area during the atomization process to form charged particles with magnetism. Under the action of electrostatic induction and magnetic adsorption, lactoferrin adheres to the surface of the collector. The device of the present invention can collect ultrafine lactoferrin powder, improve the iron saturation of lactoferrin, operate at a relatively low temperature, and can also create a sterile environment to improve product uniformity.

Description

Technical Field

[0001] The invention relates to a high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin and application thereof, and belongs to the field of dairy processing and equipment manufacturing. Background Art

[0002] Lactoferrin is a multifunctional protein with antibacterial, anti-inflammatory, and antioxidant properties. Spray drying and vacuum freeze drying are currently the main methods for preparing lactoferrin powder. However, spray drying can easily damage heat-sensitive components, while vacuum freeze drying has long drying times and high drying costs, both of which have certain limitations. High-voltage electrostatic spray drying can produce lactoferrin nanoparticles with similar charges. These particles are less prone to agglomeration due to electrostatic repulsion, have small size, good dispersibility, and can be processed at low temperatures, making them an alternative for preparing lactoferrin powder. However, the ultrafine powder produced by high-voltage electrostatic spray drying is difficult to collect. Due to lactoferrin's strong iron binding ability, the addition of inorganic iron is a common method to increase the iron saturation of lactoferrin. During the high-voltage electrostatic spray process, iron ions accumulate on the droplet surface. Upon contact with a hot medium, they are heated to form iron oxides, which impart magnetic properties to the lactoferrin powder, allowing it to be adsorbed and collected by electromagnetic attraction. This method has demonstrated advantages in the preparation of ultrafine lactoferrin powder.

[0003] Currently, there are electrostatic spray devices and methods that use electromagnetic force to promote online mixing of heterogeneous cutting fluids. For details, see CN202211081187.3, "Electrostatic spray device and method that uses electromagnetic force to promote online mixing of heterogeneous cutting fluids." This device can fully mix oil-based droplets and water-based droplets, ensuring atomization and dispersion after spraying and achieving electrostatic minimal lubrication. However, this method does not involve drying and has no electromagnetic adsorption effect, making it significantly different from this patent.

[0004] In the prior art, there is a magnetoelectric AC electrostatic ultrasonic atomizing nozzle and working method, such as CN202111494570.7, a magnetoelectric AC electrostatic ultrasonic atomizing nozzle and working method. The device accelerates the liquid sprayed into the liquid inlet pipe through the gas in the Laval tube, and then charges the atomized liquid through the charging electrode. The charged droplets enter the magnetized resonant cavity to obtain charged and magnetic droplets. The magnetic field effect of this method is realized through the magnetized resonant cavity, which is significantly different from the mode of action of magnetic particle adsorption used in the present invention.

[0005] Similarly, electrostatic spray dryer devices and methods exist in the prior art for drying liquids into powders, such as CN201980087593.0, an electrostatic spray dryer system. This method includes an electrostatic nozzle and a powder collector including a filter collection bag. Residual powder on the inner wall of the drying chamber is removed by a scraper coupled to the wall by magnetic attraction. The magnetic adsorption in this method is used for scraping the wall, and the liquid is not magnetically modified. The principle and mode of action of its magnetic adsorption are significantly different from those of the present invention.

[0006] Similarly, there is a method for preparing probiotic powder by electrostatic low-temperature spray drying, such as CN201911395581.2, which describes a method for preparing probiotic powder by electrostatic low-temperature spray drying. This method involves heat-stimulating the bacterial solution, emulsifying and encapsulating it with a protective wall material, and then electrostatically spraying and low-temperature drying it to produce a highly active probiotic powder. This method does not involve electromagnetic adsorption, significantly different from the method used in the present invention. Summary of the Invention

[0007] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin and its application, so as to carry out targeted enrichment of lactoferrin powder under the action of electromagnetic adsorption and obtain highly charged, low-particle-size, and uniformly dispersed lactoferrin powder in a relatively low-temperature environment.

[0008] The technical solution of the present invention is a high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin, which includes a liquid material feeding system, an air pressure control system, an electrostatic spray drying system and an electromagnetic adsorption system.

[0009] The liquid material feeding system specifically includes a liquid material storage tank, a liquid filter, a one-way valve, and a liquid container. The liquid material storage tank is connected to the liquid container via the one-way valve. A filter is also provided between the liquid material storage tank and the one-way valve. The bottom of the liquid container is connected to the electrostatic spray drying system via a pipe, and the top is connected to the air pressure regulation system via a pipe. The liquid material storage tank is used to store the liquid material, which is then transported to the liquid container via the liquid filter and the one-way valve.

[0010] The air pressure control system includes a high-pressure gas storage tank, an air compressor, a vacuum tank and a vacuum pump; the liquid container is connected to the high-pressure gas storage tank and the vacuum tank through pipelines respectively; the high-pressure gas storage tank is connected to the air compressor, and the vacuum tank is connected to the vacuum pump.

[0011] The air pressure control system also includes a vacuum solenoid valve, a feed valve and a pressure regulating valve; the feed valve and the pressure regulating valve are sequentially provided on the pipeline connecting the liquid container and the high-pressure gas storage tank; the vacuum solenoid valve and the pressure regulating valve are sequentially provided on the pipeline connecting the liquid container and the vacuum tank.

[0012] The air pressure regulating system is used to control the air pressure in the liquid container, including two routes: negative pressure vacuum regulation and high-pressure gas flow regulation. Negative pressure vacuum regulation is used to control the total amount of liquid in the liquid container. The top of the liquid container is connected to a vacuum tank and a vacuum pump in sequence through a pipeline. A vacuum solenoid valve is provided on the pipeline to adjust the vacuum switch, and a pressure regulating valve is provided to adjust the vacuum degree. Under the action of negative pressure, the liquid in the liquid storage tank enters the liquid container. The top of the liquid container is connected to a high-pressure gas storage tank and an air compressor in sequence through a pipeline. A feed valve control switch and a pressure regulating valve are provided on the pipeline to adjust the air pressure. The air pressure pushes the liquid in the liquid container into the electrostatic spray drying system.

[0013] The electrostatic spray drying system includes a stop valve, an electrode plate, screws, a heater, a blower, a metal needle, a drying chamber, and a high-voltage DC power supply. The input end of the stop valve is connected to a liquid container via a pipe, and the output end of the stop valve is connected to a metal needle via a pipe. The metal needle passes through the electrode plate and is fixed by a screw. The electrode plate is connected to a high-voltage DC power supply via an insulated protective copper wire. Under high voltage, the liquid is atomized into charged droplets through the metal needle. The annular top of the drying chamber is connected to a heater and a blower in sequence via a pipe. The bottom is connected to an exhaust gas recovery system via a discharge valve. Under the action of hot air, the water in the charged droplets in the drying chamber evaporates into charged particles.

[0014] The electromagnetic adsorption system includes a discharge valve, a collector, a collection plate, a magnet, a cooling plate, a cooling trough and a cooling pump; the collection plate, the magnet and the cooling plate are provided inside the collector; the top of the collector is connected to the drying chamber through the discharge valve, and the dry material is adsorbed to the surface of the collection plate through electrostatic induction and magnetic force; the bottom of the collection plate is connected to the magnet and the cooling plate in sequence; the cooling plate forms a cooling circuit with the cooling trough and the cooling pump through a pipeline.

[0015] The system also includes an exhaust gas recovery system, comprising a gas filter, a recycler, and an exhaust fan. The gas filter's input is connected to a collector via a pipe, and its output is connected to the recycler via a pipe to remove impurities from the gas. The exhaust fan is connected to the gas filter and the exhaust fan via pipes, respectively, and the filtered hot air is discharged through the exhaust fan.

[0016] It also includes a control system; the control system includes a control cabinet, which is respectively connected to a one-way valve, a vacuum solenoid valve, a feed valve, a stop valve, a pressure regulating valve, a heater, a high-voltage DC power supply, and a discharge valve; and sets and detects process parameters for each system and controls the operation of each component.

[0017] Furthermore, the liquid storage tank, liquid container and connecting pipes are all made of silicate glass material.

[0018] Furthermore, the voltage operating parameter of the high-voltage direct current power supply is set to 20-50 kV.

[0019] Furthermore, the metal needle is made of stainless steel, the needle specification is 25-34G, and the needle tube length is 20-40mm.

[0020] Furthermore, the electrode plate is made of copper and is protected by insulating shrinkage material. A hole is processed in the middle of the electrode plate with a hole diameter of 3-5 mm.

[0021] Furthermore, the drying chamber is made of silicate glass, has a height of 80-100 cm and an inner diameter of 30-50 cm.

[0022] Furthermore, the collector is made of silicate glass and has a length of 30-50 cm, a width of 30-50 cm, and a height of 20-40 cm.

[0023] Furthermore, the collecting plate is made of copper, is 30-50 cm long, 30-50 cm wide, and 2-5 cm thick, is covered with a magnetic film, and has a surface temperature controlled below 80°C.

[0024] Furthermore, the magnet is an N52 type magnet, and its temperature is controlled to be lower than 80° C. by a water cooling system.

[0025] Furthermore, the gas filter is loaded with an air filter membrane, and the filter pore size of the filter membrane is 200-1000nm.

[0026] Furthermore, the recoverer is made of silicate glass material, and the interior of the container is filled with activated carbon.

[0027] Another technical solution of the present invention is the application of a high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin, which comprises the following specific steps:

[0028] S1. Mix lactoferrin with an appropriate amount of inorganic iron solution, stir the mixture until the reaction is uniform, and then transfer the mixture to a liquid storage tank. Adjust the one-way valve, vacuum solenoid valve, and pressure regulating valve so that the liquid in the liquid storage tank is filtered through a liquid filter to intercept macromolecular particles, precipitates, and other substances that are not suitable for electrospraying, and allow soluble small molecules to enter the liquid container.

[0029] S2. Close the negative pressure vacuum route, open the high-pressure gas push route, adjust the feed valve and pressure regulating valve to allow the gas in the high-pressure gas storage tank to enter the liquid container, and the high-pressure gas pushes the liquid into the stop valve and metal needle in turn. Adjust the high-voltage DC power supply and apply voltage to the electrode plate. The liquid is ejected from the metal needle under the action of gas pressure and electric field to form charged droplets; at the same time, the air in the blower is heated by the heater and enters the drying chamber.

[0030] The water in the charged droplets evaporates and the electrostatic repulsion increases, causing the charged droplets to undergo a "Coulomb explosion" to form smaller droplets. The iron ions in the droplets are pushed to the surface of the droplets and come into contact with hot air at an extremely high specific surface area, oxidizing them into iron oxides. The dried lactoferrin powder therefore becomes magnetic.

[0031] S3. Open the discharge valve to connect it to the collector. The dried material is adsorbed onto the collection plate. The magnets beneath the plate control the surface temperature through a water cooling system, cooling plates, cooling tanks, and cooling pumps. Exhaust gas generated during drying passes through a filter to remove large molecules, while a recycler absorbs small molecules and harmful gases. Clean air is then discharged through an exhaust fan.

[0032] Furthermore, the solute of the inorganic iron solution is ferric chloride or ferric sulfate, and the solvent is deionized water.

[0033] Furthermore, the liquid filter passes through a 0.1 μm microporous filter membrane, and the gas filter is loaded with a 200-1000 nm microporous filter membrane.

[0034] Furthermore, the vacuum pump and the regulating valve jointly adjust the vacuum degree of the liquid material container, and the vacuum degree is adjusted to 50-80KPa.

[0035] Furthermore, the high-pressure gas storage tank transports inert gases such as nitrogen and argon; the transported gas pressure adjustment range is 0-1.2MPa.

[0036] Furthermore, the spray rate of the metal needle is 0-300 mL / h.

[0037] Furthermore, the voltage setting parameter of the high voltage DC power supply is 20-50 kV.

[0038] Furthermore, the magnet is an N52 type magnet, and its temperature is controlled to be below 80° C. by a water cooling system.

[0039] Furthermore, the water cooling system of the magnet uses deionized water.

[0040] Furthermore, the recoverer is loaded with activated carbon to adsorb the waste gas.

[0041] Beneficial effects of the present invention:

[0042] The present invention can collect ultrafine lactoferrin powder: traditional spray drying is limited by the separation limitations of the cyclone separator and can usually only collect micron-level lactoferrin powder. This method can effectively collect nano-lactoferrin powder and improve its solubility and bioavailability.

[0043] The present invention can improve the iron saturation of lactoferrin: lactoferrin has the ability to bind inorganic iron, and part of the inorganic iron added by pretreatment is bound by lactoferrin. The structure of lactoferrin with high iron saturation is more stable, and the iron supplementation effect is significant.

[0044] The present invention can operate at a relatively low temperature: the lactoferrin drying can be completed at an air inlet temperature of 130° C. and an air outlet temperature of 70° C.; the thermal damage to the lactoferrin caused by traditional spray drying can be avoided, the physiological activity of the lactoferrin can be retained, and the physiological activities of the lactoferrin powder, such as iron supplementation and anti-oxidation, can be improved.

[0045] The present invention can create a sterile environment: high-voltage electrostatic spray has a significant killing effect on bacteria in the feed liquid, ionized radicals generated by discharge at the tip of the metal needle inhibit the spread of bacteria in the environment, hot air curbs the reproduction of heat-sensitive bacteria, and the design of the drying chamber and collector are both conducive to the production of sterile lactoferrin powder.

[0046] This method improves product uniformity: large particles are trapped layer by layer, small molecules with electromagnetic properties enter the collection system, and small molecules without electromagnetic properties are collected by the recycler. As a result, each batch of lactoferrin powder has similar charge characteristics and particle size, thereby improving product uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic diagram of the structure of the device of the present invention.

[0048] Figure 2 It is a schematic diagram of the control principle of the present invention.

[0049] Figure numerals: 1. Liquid storage tank; 2. Liquid; 3. Liquid filter; 4. One-way valve; 5. Liquid container; 6. Vacuum solenoid valve; 7. Feed valve; 8. Stop valve; 9. Pressure regulating valve; 10. High-pressure gas storage tank; 11. Air compressor; 12. Vacuum tank; 13. Vacuum pump; 14. Electrode plate; 15. Screw; 16. Heater; 17. Blower; 18. Metal needle; 19. Drying chamber; 20. High-voltage DC power supply; 21. Discharge valve; 22. Collector; 23. Dry material; 24. Collecting plate; 25. Magnet; 26. Cooling plate; 27. Cooling trough; 28. Cooling pump; 29. ​​Gas filter; 30. Recycler; 31. Exhaust fan; 32. Control cabinet. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] Example 1

[0052] like Figure 1-2As shown, a high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin includes a liquid material feeding system, an air pressure control system, an electrostatic spray drying system and an electromagnetic adsorption system.

[0053] The liquid material feeding system specifically includes a liquid material storage tank 1, a liquid filter 3, a one-way valve 4, and a liquid container 5. The liquid material storage tank 1 is connected to the liquid container 5 through the one-way valve 4. A liquid filter 3 is also provided between the liquid material storage tank 1 and the one-way valve 4. The liquid container 5 is connected to the electrostatic spray drying system via a pipe at the bottom and the air pressure regulation system via a pipe at the top. The liquid material storage tank 1 is used to store liquid material 2, which is then transported to the liquid container 5 through the liquid filter 3 and the one-way valve 4.

[0054] The air pressure control system includes a high-pressure gas storage tank 10, an air compressor 11, a vacuum tank 12 and a vacuum pump 13; the liquid container 5 is connected to the high-pressure gas storage tank 10 and the vacuum tank 12 through pipelines; the high-pressure gas storage tank 10 is connected to the air compressor 11, and the vacuum tank 12 is connected to the vacuum pump 13;

[0055] The air pressure control system also includes a vacuum solenoid valve 6, a feed valve 7 and a pressure regulating valve 9; the feed valve 7 and the pressure regulating valve 9 are sequentially provided on the pipeline connecting the liquid container 5 and the high-pressure gas storage tank 10; the vacuum solenoid valve 6 and the pressure regulating valve 9 are sequentially provided on the pipeline connecting the liquid container 5 and the vacuum tank 12.

[0056] The air pressure regulating system is used to control the air pressure in the liquid container 5, including two routes: negative pressure vacuum regulation and high-pressure gas flow regulation. Negative pressure vacuum regulation is used to control the total amount of liquid 2 in the liquid container 5. The top of the liquid container 5 is connected to the vacuum tank 12 and the vacuum pump 13 in sequence through a pipeline. A vacuum solenoid valve 6 is provided on the pipeline to adjust the vacuum switch, and a pressure regulating valve 9 is provided to adjust the vacuum degree. Under the action of negative pressure, the liquid 2 in the liquid storage tank 1 enters the liquid container 5. The top of the liquid container 5 is connected to the high-pressure gas storage tank 10 and the air compressor 11 in sequence through a pipeline. A feed valve 7 is provided on the pipeline to control the switch, and a pressure regulating valve 9 is provided to adjust the air pressure. The air pressure pushes the liquid 2 in the liquid container 5 into the electrostatic spray drying system.

[0057] The electrostatic spray drying system includes a stop valve 8, an electrode plate 14, a screw 15, a heater 16, a blower 17, a metal needle 18, a drying chamber 19, and a high-voltage DC power supply 20; the input end of the stop valve 8 is connected to the liquid container 5 through a pipe, and the output end of the stop valve 8 is connected to the metal needle 18 through a pipe. The metal needle 18 passes through the electrode plate 14 and is fixed by the screw 15. The electrode plate 14 is connected to the high-voltage DC power supply 20 through an insulated protective copper wire. Under high voltage, the liquid 2 is atomized into charged droplets through the metal needle 18. The annular top of the drying chamber 19 is connected to the heater 16 and the blower 17 in sequence through a pipe. The bottom is connected to the exhaust gas recovery system through a discharge valve 21. Under the action of hot air, the water in the charged droplets in the drying chamber 19 evaporates into charged particles.

[0058] The electromagnetic adsorption system includes a discharge valve 21, a collector 22, a collection plate 24, a magnet 25, a cooling plate 26, a cooling trough 27 and a cooling pump 28; the collector 22 is provided with a collection plate 24, a magnet 25 and a cooling plate 26; the top of the collector 22 is connected to the drying chamber 19 through the discharge valve 21, and the dry material 23 is adsorbed to the surface of the collection plate 24 through electrostatic induction and magnetic force; the bottom of the collection plate 24 is connected in sequence to the magnet 25 and the cooling plate 26; the cooling plate 26 forms a cooling circuit with the cooling trough 27 and the cooling pump 28 through a pipeline.

[0059] The system also includes an exhaust gas recovery system, comprising a gas filter 29, a recycler 30, and an exhaust fan 31. The gas filter 29 is connected to the collector 22 via a pipe at its input and to the recycler 30 at its output via a pipe to remove impurities from the gas. The exhaust fan 31 is connected to the gas filter 29 and the exhaust fan 31 via pipes. The filtered hot air is discharged through the exhaust fan 31.

[0060] It also includes a control system; the control system includes a control cabinet 32, which is respectively connected to a one-way valve 4, a vacuum solenoid valve 6, a feed valve 7, a stop valve 8, a pressure regulating valve 9, a heater 16, a high-voltage DC power supply 20 and a discharge valve 21; and sets and detects process parameters for each system and controls the operation of each component.

[0061] Furthermore, the liquid storage tank, liquid container and connecting pipes are all made of silicate glass material.

[0062] Furthermore, the voltage operating parameter of the high-voltage direct current power supply is set to 20-50 kV.

[0063] Furthermore, the metal needle is made of stainless steel, the needle specification is 25-34G, and the needle tube length is 20-40mm.

[0064] Furthermore, the electrode plate is made of copper and is protected by insulating shrinkage material. A hole is processed in the middle of the electrode plate with a hole diameter of 3-5 mm.

[0065] Furthermore, the drying chamber is made of silicate glass, has a height of 80-100 cm and an inner diameter of 30-50 cm.

[0066] Furthermore, the collector is made of silicate glass and has a length of 30-50 cm, a width of 30-50 cm, and a height of 20-40 cm.

[0067] Furthermore, the collecting plate is made of copper, is 30-50 cm long, 30-50 cm wide, and 2-5 cm thick, is covered with a magnetic film, and has a surface temperature controlled below 80°C.

[0068] Furthermore, the magnet is an N52 type magnet, and its temperature is controlled to be lower than 80° C. by a water cooling system.

[0069] Furthermore, the gas filter is loaded with an air filter membrane, and the filter pore size of the filter membrane is 200-1000nm.

[0070] Furthermore, the recoverer is made of silicate glass material, and the interior of the container is filled with activated carbon.

[0071] The following is further explained using the application of Example 1:

[0072] Application Example 1 High-voltage electrostatic spray drying method for electromagnetically adsorbed lactoferrin using ferric chloride pretreatment

[0073] S1. Prepare 100 mL of 0.1 mol / L ferric chloride aqueous solution, mix with 1 L of 10% (w / v) lactoferrin solution, stir evenly at 500 rpm at room temperature, and transfer to liquid storage tank 1. Open one-way valve 4, vacuum solenoid valve 6, pressure regulating valve 9, and vacuum pump 13, and adjust the vacuum to 50 kPa. Under the action of the vacuum negative pressure, liquid 2 enters liquid container 5.

[0074] S2. Close the one-way valve 4, vacuum solenoid valve 6, pressure regulating valve 9, and vacuum pump 13. Open the feed valve 7, stop valve 8, pressure regulating valve 9, and air compressor 11, adjusting the air pressure to 0.6 MPa. Nitrogen from the high-pressure gas storage tank 10 enters the liquid container 5. The nitrogen pushes the liquid 2 into the metal needle 18 (needle gauge 34G), forming a spray in the drying chamber 19. Simultaneously, turn on the heater 16 and blower 17, allowing hot air to enter the high-voltage electrostatic spray drying system through the annular top of the drying chamber 19. The heater temperature is set to 130°C.

[0075] S3. Open discharge valve 21 and exhaust fan 31 to exhaust the hot air. After stabilizing for 5 minutes, turn on cooling pump 28 to cool the surface of magnet 25. Every 2 hours, remove the lactoferrin powder from collection plate 24. Every 2 hours, check and replace the microporous filter membrane on gas filter 29.

[0076] Product inspection and evaluation: Lactoferrin powder has a yield of 90%, dark red color, moisture content less than 4%, iron content less than 30mg / 100g, particle size 200-400nm, water solubility greater than 90%, and total colony count less than 100CFU / g.

[0077] Application Example 2 High-voltage electrostatic spray drying method for electromagnetically adsorbed lactoferrin using ferrous sulfate pretreatment

[0078] S1. Prepare 100 mL of 0.1 mol / L ferrous sulfate aqueous solution, mix with 1 L of 20% (w / v) lactoferrin solution, stir evenly at 500 rpm at room temperature, and transfer to liquid storage tank 1. Open one-way valve 4, vacuum solenoid valve 6, pressure regulating valve 9, and vacuum pump 13, and adjust the vacuum degree to 80 kPa. Under the vacuum negative pressure, liquid 2 enters liquid container 5.

[0079] S2. Close the one-way valve 4, vacuum solenoid valve 6, pressure regulating valve 9, and vacuum pump 13. Open the feed valve 7, stop valve 8, pressure regulating valve 9, and air compressor 11, adjusting the air pressure to 0.6 MPa. Nitrogen from the high-pressure gas storage tank 10 enters the liquid container 5. The nitrogen pushes the liquid 2 into the metal needle 18 (needle gauge 32G), forming a spray in the drying chamber 19. Simultaneously, turn on the heater 16 and blower 17, allowing hot air to enter the high-voltage electrostatic spray drying system through the annular top of the drying chamber 19. The heater temperature is set to 120°C.

[0080] S3. Open discharge valve 21 and exhaust fan 31 to exhaust the hot air. After stabilizing for 5 minutes, turn on cooling pump 28 to cool the surface of magnet 25. Every 2 hours, remove the lactoferrin powder from collection plate 24. Every 2 hours, check and replace the microporous filter membrane on gas filter 29.

[0081] Product inspection and evaluation: Lactoferrin powder has an 80% yield, dark red color, moisture content less than 3%, iron content less than 20mg / 100g, particle size 200-500nm, water solubility greater than 90%, and total colony count less than 100CFU / g.

[0082] The above embodiments are intended only to illustrate the design concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. The scope of protection of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design concepts disclosed in the present invention are within the scope of protection of the present invention.

Claims

1. A high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin, characterized by: Including liquid material feeding system, air pressure control system, electrostatic spray drying system and electromagnetic adsorption system; The liquid material feeding system specifically comprises a liquid material storage tank (1), a filter (3), a one-way valve (4) and a liquid material container (5); the liquid material storage tank (1) is connected to the liquid material container (5) through the one-way valve (4); a filter (3) is further provided between the liquid material storage tank (1) and the one-way valve (4); the bottom of the liquid material container (5) is connected to the electrostatic spray drying system through a pipeline, and the top is connected to the air pressure regulating system through a pipeline; The air pressure control system comprises a high-pressure gas storage tank (10), an air compressor (11), a vacuum tank (12) and a vacuum pump (13); the liquid material container (5) is connected to the high-pressure gas storage tank (10) and the vacuum tank (12) through pipelines; the high-pressure gas storage tank (10) is connected to the air compressor (11), and the vacuum tank (12) is connected to the vacuum pump (13); The electrostatic spray drying system comprises a stop valve (8), an electrode plate (14), a screw (15), a heater (16), an air blower (17), a metal needle (18), a drying chamber (19), and a high-voltage DC power supply (20); the input end of the stop valve (8) is connected to the liquid container (5) through a pipeline, and the output end is connected to the metal needle (18) through a pipeline; the metal needle (18) passes through the electrode plate (14) and is fixed by a screw (15); the electrode plate (14) is connected to the high-voltage DC power supply (20) through an insulating protective copper wire; the annular top of the drying chamber (19) is connected to the heater (16) and the air blower (17) in sequence through a pipeline; The electromagnetic adsorption system includes a discharge valve (21), a collector (22), a collection plate (24), a magnet (25), a cooling plate (26), a cooling trough (27) and a cooling pump (28); the top of the collector (22) is connected to the bottom of the drying chamber (19) through the discharge valve (21); the collector (22) is provided with a collection plate (24), a magnet (25) and a cooling plate (26); the bottom of the collection plate (24) is connected to the magnet (25) and the cooling plate (26) in sequence; the cooling plate (26) forms a cooling circuit with the cooling trough (27) and the cooling pump (28) through a pipeline.

2. The high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The air pressure control system further comprises a vacuum solenoid valve (6), a feed valve (7) and a pressure regulating valve (9); the feed valve (7) and the pressure regulating valve (9) are sequentially provided on the pipeline connecting the liquid container (5) and the high-pressure gas storage tank (10); and the vacuum solenoid valve (6) and the pressure regulating valve (9) are sequentially provided on the pipeline connecting the liquid container (5) and the vacuum tank (12).

3. The high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The invention also includes an exhaust gas recovery system; the exhaust gas recovery system includes a gas filter (29), a recovery device (30) and an exhaust fan (31); the input end of the gas filter (29) is connected to the collector (22) through a pipeline, and the output end is connected to the recovery device (30) through a pipeline; the exhaust fan (31) is connected to the gas filter (29) and the exhaust fan (31) through pipelines.

4. The high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The system further comprises a control system; the control system is specifically a control cabinet (32); the control cabinet (32) is respectively connected to a one-way valve (4), a vacuum solenoid valve (6), a feed valve (7), a stop valve (8), a pressure regulating valve (9), a heater (16), a high-voltage DC power supply (20) and a discharge valve (21).

5. The high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The metal needle (18) is made of stainless steel, with a needle gauge of 25-34G and a needle tube length of 20-40mm.

6. The high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The drying chamber has a height of 80-100 cm and an inner diameter of 30-50 cm; The collector (22) is 30-50 cm long, 30-50 cm wide, and 20-40 cm high; The collecting plate (24) is made of copper, 30-50 cm long, 30-50 cm wide, 2-5 cm thick, and covered with a magnetic film; The electrode plate (14) is made of copper and is protected by insulating shrinkage material. A hole is processed in the middle of the electrode plate, and the hole diameter is 3-5 mm.

7. The high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin as claimed in claim 3, characterized in that: The filter (3) passes through a 0.1µm microporous membrane; The gas filter (29) is loaded with an air filter membrane, and the filter pore size of the filter membrane is 200-1000 nm; The interior of the recycler (30) container is filled with activated carbon.

8. The high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin according to claim 1, characterized in that: The liquid material storage tank (1), liquid material container (5), drying chamber (19), collector (22), recovery device (30) and various connecting pipes are all made of silicate glass material.

9. Use of the high-voltage electrostatic spray drying device for low-flux electromagnetic adsorption of lactoferrin according to any one of claims 2 to 8, characterized in that Specific steps as follows: S1. Lactoferrin is mixed with an appropriate amount of inorganic iron solution, stirred to react evenly, and then transferred to a liquid material storage tank (1). The one-way valve (4), vacuum solenoid valve (6) and pressure regulating valve (9) are adjusted so that the liquid material (2) in the liquid material storage tank (1) is filtered through the filter (3), and substances not suitable for electrospraying are retained, while soluble small molecules enter the liquid material container (5); S2, close the negative pressure vacuum route, open the high-pressure gas push route, adjust the feed valve (7) and the pressure regulating valve (9) to allow the gas in the high-pressure gas storage tank (10) to enter the liquid container (5), and the high-pressure gas pushes the liquid (2) to enter the stop valve (8) and the metal needle (18) in sequence; adjust the high-voltage DC power supply (20), apply voltage to the electrode plate (14), and the liquid (2) is ejected from the metal needle (18) under the action of gas pressure and electric field to form charged droplets; at the same time, the air in the blower (17) is heated by the heater (16) and enters the drying chamber (19); S3. Open the discharge valve (21) to connect it to the collector (22). The dried material (23) is adsorbed on the collecting plate (24). The magnet (25) under the collecting plate (24) controls its surface temperature through a water cooling system. The waste gas generated during the drying is filtered by a gas filter (29) to remove large molecular substances. The recovery device (30) adsorbs small molecular substances and harmful gases. The clean air is discharged through the exhaust fan (31).

10. The application of the high-voltage electrostatic spray drying device for low-throughput electromagnetic adsorption of lactoferrin as claimed in claim 9, characterized in that During use of the device: The voltage operating parameter of the high voltage DC power supply (20) is set to 20-50 kV; The surface temperature of the collecting plate (24) is controlled below 80°C; The temperature of the magnet (25) is controlled to be below 80°C by a water cooling system; The vacuum degree of the liquid container is adjusted by a vacuum pump (13) and a pressure regulating valve (9) to a value of 50-80 kPa; The high-pressure gas storage tank (10) delivers nitrogen or argon, and the delivery gas pressure adjustment range is 0-1.2MPa.

Images