KR101989046B1 - Sterilizing apparatus for powder foods using plasma - Google Patents

Abstract

The present invention relates to a powder sterilizing apparatus using plasma, and is intended to sterilize harmful microorganisms present on the surface of a micron-sized powder food by surface treatment using a low-temperature vacuum plasma. The sterilizing gas is supplied together with the process gas necessary for plasma generation in a state in which the rotary chamber containing the powdered food is rotated and a plasma is generated around the tubular electrode portion by using a vacuum discharge in the rotary chamber to sterilize the powdered food. At this time, by circulating the refrigerant in the tubular electrode portion to suppress the temperature rise around the tubular electrode portion, temperature rise due to the plasma formed around the tubular electrode portion can be suppressed. By regularly rotating the powdered food through the rotation of the rotating chamber, the local temperature rise of the powdered food in the rotating chamber can be suppressed and the sterilization can be effectively performed through the uniform surface treatment.

Description

[0001] Sterilizing apparatus for powder foods using plasma [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder sterilizing apparatus for powder food, and more particularly, to a powder sterilizing apparatus using plasma for sterilizing harmful microorganisms present on the surface of powdery micron sized food using a low-temperature vacuum plasma will be.

Recently, as the market for health supplements has expanded rapidly, various kinds of products have been introduced and they are manufactured in various forms such as liquid, powder, and capsule. Hygiene safety is important in the production of health supplements.

Micron-sized powdered health supplements go through a series of manufacturing processes that are produced and packaged in a system that meets hygienic standards. However, there is a possibility of contamination with food poisoning bacteria (Salmonella spp., O157: H7, Campylobacter jejuni, Campylobacter coli and Yersinia enterocolitica etc.) and other harmful microorganisms which are harmful to human body by exposure and contact with unwanted environment such as air during manufacturing.

In general, health supplements such as vitamins and minerals are manufactured using powdered raw materials, and the possibility of bacterial contamination due to air exposure during the manufacturing process in a clean process system can not be excluded. Furthermore, if the powdered food is contaminated with microorganisms, the powdered food will be lumpy or corrupt due to the increase in the number of microorganisms , resulting in a decrease in water dispersibility and loss of function of the product. The burden can be increased.

In order to solve such a problem, it is desirable to inspect whether or not the whole powdery food is contaminated. However, if the whole water test is performed, the manufacturing yield may be lowered and the manufacturing cost may increase.

Therefore, since the powdered food is also a food, it is impossible to exclude the possibility of contamination. Therefore, to achieve a reliable hygiene up to the final packaging stage of the product by using a device capable of surface sterilization before the packaging machine, It is important to improve hygiene and distribution safety of products.

Conventional sterilization technologies are mostly high-temperature and high-pressure type, and they are concentrated on medical devices and their application range is limited for the treatment of surgical tools and medical materials. When the high-temperature high-pressure and chemical wet process is applied to the powdered food, the quality of the original ingredient of the powdered food to be treated may be changed, or the residue of the reaction material may remain in the surface layer of the powdered food. Devices using low-temperature plasma by dry sterilization have been developed but are not suitable for food use because they are designed for small medical instruments and materials. In addition, there is a case in which a device for obtaining a short-time sterilization effect by using atmospheric pressure plasma is applied to the field of dental instruments. However, when this device is applied to sterilization treatment of powdery foods, It is very high and the powdered food is lighter and floats in the air like dust, so that it can be blown out of the effective treatment range, so that sterilization treatment may not be possible.

Korean Registered Patent No. 10-1571238 (Registered Nov. 17, 2015)

Powdered foods are often more irregular than those with smooth spherical shapes. If uneven surface sterilization is performed due to this, harmful microorganisms locally remain in a fine portion of the powdered food, and there is a high possibility that the microorganism will reproduce again. Therefore, there is a demand for a surface disinfection technique suitable for powdered foods.

In powdered foods, more than necessary temperature may be applied to powdered foods during surface disinfection. When the temperature-sensitive ingredients of the powdered food are contained, the viscosity of the powdered food is lowered due to the increase in the temperature during sterilization of the surface, so that the powdered food may be pressed against the processing container containing the powdered food, .

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a powder food sterilizing apparatus using a plasma which can uniformly sterilize powdered food.

It is another object of the present invention to provide a powder food sterilizing apparatus using plasma which can suppress the pressing of powdery foods to the processing container due to a temperature higher than necessary in the powdery food during the surface sterilization process.

It is another object of the present invention to provide a powder sterilization apparatus using plasma which can stably perform uniform surface sterilization in a single process at a low temperature without any risk of contamination due to external exposure.

In order to achieve the above object, the present invention provides a powder food sterilizing apparatus using plasma, which sterilizes harmful microorganisms present on the micron-sized powder food surface through a surface treatment using a low-temperature vacuum plasma.

The present invention relates to a rotation device, A rotary chamber into which the powdered food is introduced and which rotates the powdery food while being rotated by the rotary unit; A vacuum pump connected to the rotary chamber for generating a vacuum in the rotary chamber; A tubular electrode unit having an electrode tube fixedly installed in the rotary chamber and installed close to an inner circumferential surface of the rotary chamber to which the powdered food is injected and rotating, and having a tubular shape in which the refrigerant circulates into the electrode tube; A gas supply unit fixedly installed in the rotary chamber, the gas supply unit having a shower head for supplying a process gas for plasma generation and sterilizing gas around the electrode tube; And an AC voltage is applied between the electrode tube and the rotating chamber in a state where the rotating chamber is in a vacuum state to generate an AC voltage between the electrode tube and the rotating chamber based on a process gas and a sterilizing gas supplied through the shower head And an AC power source for sterilizing the powdered food in the rotating chamber with a plasma.

The rotating chamber includes a pair of fixed flanges spaced apart from each other in a disk shape and to which the tubular electrode unit and the gas supply unit are fixed. A pair of rotation flanges rotatably coupled to the pair of fixing flanges in a ring shape while maintaining a vacuum state through a plurality of O-rings; And an inner space into which the powdered food is introduced in the form of a tube surrounding the pair of rotating flanges, wherein the inner and outer peripheral surfaces are uniformly formed with irregularities, and the powdered food is rolled while rotating together with the pair of rotating flanges, And a chamber tube electrically connected to the AC power source.

The tubular electrode unit includes a refrigerant inlet tube for receiving refrigerant from the outside of the rotary chamber; An electrode tube connected to the coolant injection tube and installed near the inner circumferential surface of the chamber tube through the fixing flange and generating a plasma by receiving an AC voltage; And a refrigerant discharge pipe connected to the electrode tube and discharging the refrigerant out of the rotary chamber through the fixing flange.

The showerhead of the gas supply part may be formed long along the axial direction of the chamber tube. The electrode tube may be formed in a loop shape surrounding the showerhead.

And one of the pair of fixing flanges is provided with a mounting hole for fixing the tubular electrode portion and the gas supply portion.

The powder food sterilizing apparatus according to the present invention may further include a sealing assembly for sealing the mounting hole and fixing the tubular electrode part and the gas supplying part to the mounting hole.

Wherein the sealing assembly comprises: a mounting plate installed inside the rotating chamber and having a size to cover the mounting hole, the tubular electrode unit and the gas supply unit being installed; An insulating plate interposed between the mounting plate and the fixing flange and having an insertion hole into which the tubular electrode portion and the gas supply portion are inserted; A tubular electrode portion connected to the insertion hole of the insulating plate and drawn out of the fixing flange through the mounting hole to protect the tubular electrode portion and the gas supply portion; A fastening member for fixing the mounting plate to the fixing flange via the insulating plate; And a vacuum o-ring interposed between the mounting plate, the insulating plate, and the fixing flange.

The electrode tube may be disposed at an angle of less than 90 degrees with a vertical line in a direction in which the chamber tube rotates with respect to a vertical line drawn from the rotation axis of the chamber tube to a horizontal plane.

The rotation unit rotates the rotation chamber at 5 to 20 rpm.

The vacuum pump maintains the inside of the rotating chamber at 10 ^-2 to 10 ^-1 torr.

The AC power source applies a middle frequency, RF or microwave alternating voltage of 5 to 25 kV.

The process gas may comprise nitrogen, oxygen, argon or helium.

And the sterilizing gas may comprise hydrogen peroxide or alcohols.

According to the present invention, harmful microorganisms present on the micron sized powder food surface can be sterilized by surface treatment using a low-temperature vacuum plasma.

In the vacuum plasma treatment, the temperature rise due to the plasma formed around the tubular electrode portion can be suppressed by circulating the refrigerant in the tubular electrode portion to suppress the temperature rise around the tubular electrode portion. By regularly rotating the powdered food through the rotation of the rotating chamber, the local temperature rise of the powdered food in the rotating chamber can be suppressed and the sterilization can be effectively performed through the uniform surface treatment.

Since the powder food sterilizing apparatus according to the present invention sterilizes the surface of the powdered food by the plasma uniformly generated in the vacuum state, it does not cause unwanted contamination from the outside during sterilization and gives a sterilization effect to the local portion of the powdered food .

The powder food sterilizing apparatus according to the present invention can be used by mixing a sterilizing gas according to the characteristics of various kinds of harmful bacteria to be sterilized and can rotate while maintaining a vacuum, It is possible to effectively remove only harmful bacteria on the surface without damaging the original components of the apparatus.

1 is a block diagram showing a powder sterilizing apparatus using plasma according to an embodiment of the present invention.
FIG. 2 is a view showing a powder sterilizing apparatus using plasma shown in FIG. 1. FIG.
Figure 3 is a cross-sectional view of the chamber tube of the rotating chamber of Figure 2;
FIG. 4 is a perspective view showing a state where a showerhead of a gas supply unit is disposed between electrode tubes of the tubular electrode unit of FIG. 2. FIG.
FIG. 5 is a view showing a state in which a tubular electrode portion and a gas supply portion are provided in the sealing assembly of FIG. 2. FIG.
FIGS. 6 and 7 are views for explaining the position of the electrode tube with respect to the rotary chamber for generating a vacuum plasma.

In the following description, only parts necessary for understanding embodiments of the present invention will be described, and descriptions of other parts will be omitted to the extent that they do not disturb the gist of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and the inventor is not limited to the meaning of the terms in order to describe his invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely preferred embodiments of the present invention, and are not intended to represent all of the technical ideas of the present invention, so that various equivalents And variations are possible.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a powder sterilizing apparatus using plasma according to an embodiment of the present invention.

Referring to FIG. 1, the powder food sterilizing apparatus 100 according to the present embodiment is a device for sterilizing harmful microorganisms present on the micron-sized powder food surface by using a plasma treatment.

The powder food sterilizing apparatus 100 according to the present embodiment includes a rotary unit 10, a rotary chamber 20, a vacuum pump 40, a tubular electrode unit 50, a gas supply unit 60, and an AC power source 70 . Here, the rotation unit 10 rotates the rotation chamber 20. The rotary chamber 20 is charged with powdered food, and rotates the powdered food while it is rotated by the rotary part 10. [ The vacuum pump 40 is connected to the rotating chamber 20 to make the inside of the rotating chamber 20 vacuum. The tubular electrode unit 50 includes an electrode tube 53 fixedly installed in the rotary chamber 20 and disposed adjacent to the inner circumferential surface of the rotating chamber 20 in which the powdered food is injected and rotated, The refrigerant circulates in the form of a tube. The gas supply part 60 is fixedly installed in the rotary chamber 20 and has a shower head 61 for supplying a process gas for plasma generation and sterilizing gas around the electrode tube 53. The AC power source 70 applies an AC voltage between the electrode tube 53 and the rotary chamber 20 while the rotary chamber 20 is in a vacuum state so that the process gas and sterilizing gas supplied through the shower head 61 The plasma generated between the electrode tube 53 and the inner circumferential surface of the rotary chamber 20 sterilizes the powdery food in the rotary chamber 20.

Here, the reason why vacuum plasma is used to sterilize the powdered food is as follows.

First, plasma application technology is widely used in the fields of surface treatment and synthesis of new materials. Especially, it is an indispensable technology in industrial fields requiring special surface treatment and modification such as metals, oil / minerals, and polymer materials. At present, active application researches in the aerospace and medical fields are being carried out all over the world by utilizing their inherent physicochemical and electrical characteristics.

Recently, interest in application of plasma to the food field has been increasing, and research has been carried out to apply plasma technology to food processing. In some cases, for example, application of surface treatment such as fruits and vegetables has been reported. However, there is no practical application of surface sterilization device for fine powdered food. Therefore, the surface sterilization device for powdered foods will provide a technical basis for supplying hygienic powdered foods to the food companies.

Plasma is a technique applied mainly in a gaseous state, and can be divided into a vacuum plasma and an atmospheric plasma depending on the generation method. The atmospheric plasma has a plasma jet method and a dielectric discharge plasma method according to a generation method. The plasma jet method has a disadvantage in that the surface area of the plasma jetted from the nozzle is small although the plasma jet method can produce a relatively high density plasma as compared with the dielectric discharge plasma. The dielectric discharge system has a structure capable of large-area processing, but the effective distance to the surface of the object to be treated is short because the plasma to be sprayed is short, which is disadvantageous for treating a rough object and a complicated object.

In the vacuum plasma method, which is widely applied in the field of semiconductor and LED, there is a limitation in the size of the object to be treated and the complex device is complex. However, the surface of the complex object The advantage is that it can be treated uniformly.

The vacuum plasma method is advantageous in that it can be processed to a gas particle size level at the surface of the amorphous powder which is too fine to be accessed.

Therefore, the powder food sterilizing apparatus according to the present embodiment uses a vacuum plasma to sterilize powdered food.

On the other hand, it is necessary to suppress the influence on the powder food due to the temperature rise around the electrode and the electrode where the plasma is generated. In order to solve this problem, the powder food sterilizing apparatus 100 according to the present embodiment employs a method of circulating the refrigerant into the electrode tube 53. [ By rotating the powder food regularly through the rotation of the rotary chamber 20, it is possible to suppress the uniform sterilization treatment of the powdered food and the local temperature rise.

As the amount of the powdered food is larger, the distance between the electrode and the chamber becomes longer, the influence of the alternating electric field becomes smaller, and plasma generation becomes difficult, so that continuous discharge is difficult. Therefore, the powder sterilizing apparatus 100 according to the present embodiment maintains the plasma generating space by positioning the electrode tube 53 at the portion where the rotating chamber 20 and the powdery food are exposed at the same time. A detailed description thereof will be described later.

The powder food sterilizing apparatus 100 according to the present embodiment is designed in consideration of this point, and will be described in detail with reference to FIGS. 1 to 5 as follows. Here, FIG. 2 is a view showing the plasma sterilizing apparatus 100 using plasma shown in FIG. 3 is a cross-sectional view showing the chamber tube 29 of the rotary chamber 20 of FIG. 4 is a perspective view showing a state in which the shower head 61 of the gas supply unit 60 is disposed between the electrode tubes 53 of the tubular electrode unit 50 of FIG. 5 is a view showing a state in which the tubular electrode unit 50 and the gas supply unit 60 are installed in the sealing assembly 80 of FIG.

The rotation unit 10 rotates the rotation chamber 20. [ The rotary unit 10 rotates at a speed such that the powdered food put into the rotary chamber 20 can be uniformly mixed, for example, 5 to 20 rpm. The rotational speed of the rotary part 10 can be changed according to the amount of the powdered food put into the rotary chamber 20 and the size of the rotary chamber 20. [

The rotating portion 10 includes a motor having a driving shaft for transmitting a driving force to the rotating chamber 20. The rotation unit 10 can transmit the driving force directly to the rotation chamber 20 through the driving shaft and rotate the rotation. Alternatively, the rotary part 10 may indirectly transmit the driving force through the power transmitting member such as a pulley, a belt, a roller, or the like to rotate the rotary chamber 20.

The rotary unit 10 transmits the driving force to the rotating chamber tube 29 of the rotary chamber 20.

The rotary chamber 20 is a single chamber in the form of a cylinder, as shown in Figs. The rotation chamber 20 includes a pair of fixing flanges 21 and 23, a pair of rotation flanges 25 and 27, and a chamber tube 29.

The pair of fixing flanges 21 and 23 are provided in a disc shape so as to be spaced apart from each other, and the tubular electrode unit 50 and the gas supply unit 60 are fixed. The pair of rotation flanges 25 and 27 are rotatably coupled to the pair of fixing flanges 21 and 23 in the form of a ring plate while maintaining a vacuum state via a plurality of O-rings 24a and 24b, respectively. The chamber tube 29 is formed with an inner space 33 into which powder foods are introduced in the form of a tube surrounding a pair of rotation flanges 25 and 27 and is provided with uniform irregularities 31 on the inner peripheral surface thereof, And is electrically connected to the power source 70.

Here, the pair of fixing flanges 21 and 23 includes a first fixing flange 21 and a second fixing flange 23.

The tubular electrode portion 50 and the gas supply portion 60 are fixed to the first fixing flange 21 via the sealing assembly 80. The first fixing flange 21 may be provided with a vent valve 37 for opening and closing a gas vent inside the rotary chamber 20.

An exhaust line 41 of the vacuum pump 40 is fixed to the second fixing flange 23. The second fixing flange 23 may be provided with a vacuum gauge 45 for measuring the vacuum pressure of the rotary chamber 20. The second fixing flange 23 may be provided with a temperature sensor 47 such as a thermocouple capable of measuring the temperature around the electrode tube 53 and the electrode tube 53.

The pair of rotation flanges 25, 27 includes a first rotation flange 25 and a second rotation flange 27. The first rotation flange 25 is connected to the first fixing flange 21 via a plurality of first O-rings 24a. The second rotating flange 27 is connected to the second fixing flange 23 via a plurality of second O-rings 24b. The vacuum state between the fixing flanges 21 and 23 and the rotary flanges 25 and 27 is maintained through the first and second O-rings 24a and 24b and the rotary flanges 25 and 25 are fixed to the fixing flanges 21 and 23. [ 27 rotate.

The chamber tube 29 is coupled to a pair of rotation flanges 25 and 27 to form an internal space 33. A vacuum o-ring 35 is interposed in the portion where the chamber tube 29 and the pair of rotation flanges 25 and 27 overlap. In the present embodiment, two vacuum o-rings 35 are interposed between the chamber tube 29 and the rotary flanges 25 and 27, but the present invention is not limited thereto.

As shown in Fig. 3, the chamber tube 29 is uniformly provided with concavities and convexities 31 on its inner peripheral surface. The reason for forming the projections and depressions 31 is to uniformly expose the powdered food put into the chamber tube 29 to the plasma in the chamber tube 29 while being uniformly mixed by the rotation of the chamber tube 29.

That is, when the sterilizing process using the plasma for the powdered food is performed while the chamber tube 29 is fixed, the powdered food exposed in the inner space 33 of the chamber tube 29 is smoothly sterilized by the plasma . However, since the powdery food near the inner circumferential surface of the chamber tube 29 is not directly exposed to the plasma, sterilization by the plasma may not be performed smoothly.

Therefore, by mixing the powdery food put into the chamber tube 29 through the rotation of the chamber tube 29, the frequency of the powdery foods being exposed to the plasma is increased, so that the sterilization treatment can be performed smoothly. Further, by forming the projections and depressions 31 on the inner circumferential surface of the chamber tube 29, the powdered food put into the chamber tube 29 can be mixed more smoothly.

The shape of the unevenness 31 formed on the inner peripheral surface of the chamber tube 29 may be round or pointed. For example, the irregularities 31 may be formed in various shapes such as a hemispherical shape, a semi-elliptical shape, and a triangular shape. The irregularities 31 may be formed in an embossed shape or a bar shape. When the concavities and convexities 31 are formed in a bar shape, it is preferable that the concavities and convexities 31 are formed long in the direction of the rotation axis of the chamber tube 29, and they may be formed as a straight line, a sine wave,

The vacuum pump 40 is connected to the inner space 33 of the rotary chamber 20 via the exhaust line 41 to make the inner space 33 of the rotary chamber 20 in a vacuum state. At this time, the exhaust line 41 is connected to the inner space 33 of the rotary chamber 20 through the second fixing flange 23. An opening / closing valve 43 may be provided between the vacuum pump 40 and the exhaust line 41. As the vacuum pump 40, a rotary pump or a dry pump may be used.

The vacuum pump 40 forms a vacuum state in which the vacuum plasma can be formed in the rotary chamber 20, for example, a vacuum state of 10 ^-1 to 10 ^-3 torr. In this vacuum state, the process gas and the sterilizing gas are introduced into the rotary chamber 20 through the gas supply unit 60.

The tubular electrode unit 50 includes a refrigerant inlet tube 51, an electrode tube 53, and a refrigerant outlet tube 55 connected to one tube line, as shown in Figs. 2, 4 and 5. The refrigerant inlet tube 51 receives the refrigerant from the outside of the rotary chamber 20. The electrode tube 53 is connected to the coolant injection tube 51 and is disposed adjacent to the inner circumferential surface of the chamber tube 29 through the first fixing flange 21 to generate plasma by receiving an AC voltage. The refrigerant discharge pipe 55 is connected to the electrode pipe 53 to discharge the refrigerant out of the rotary chamber 20 through the first fixing flange 21.

At this time, the refrigerant circulation unit 56 is connected to the refrigerant injection pipe 51 and the refrigerant discharge pipe 55 to circulate the refrigerant. The refrigerant circulation unit 56 includes a refrigerant supply tank 57 and a heat exchanger 58. The coolant supply tank 57 is connected to the coolant injection pipe 51 to supply cooled coolant. The heat exchanger (58) receives the heated refrigerant from the refrigerant discharge pipe (55) and cools the heated refrigerant again through heat exchange. The heat exchanger (58) again supplies the cooled refrigerant to the refrigerant supply tank (57) to circulate the refrigerant.

The electrode tube 53 is formed in a loop shape as an electrode for generating a vacuum plasma by receiving an AC voltage from the AC power source 70. The electrode tube 53 may be formed long in the direction of the rotation axis of the rotary chamber 20.

The gas supply unit 60 supplies the process gas and sterilizing gas necessary for vacuum plasma generation into the rotary chamber 20 through the first fixing flange 21. The gas supply unit 60 includes a process gas supply tank 63, a sterilizing gas bubbler 65 and a shower head 61 and is connected to a process gas supply tank 63, a sterilizing gas bubbler 65, 61 are connected via a gas supply line 62. A valve 67 for opening and closing the gas supply and a flow meter 64 for controlling the gas supply amount are connected to the gas supply line 62.

The process gas supplied from the process gas supply tank 63 may be nitrogen, oxygen, argon, helium, or the like, but is not limited thereto. In this embodiment, two supply gas supply tanks 63 supply nitrogen gas and argon gas.

The sterilizing gas bubbler 65 contains a low molecular weight liquid compound capable of gasification and is connected to the process gas supply tank 63. The sterilizing gas bubbler 65 converts the liquid compound into a sterilizing gas through bubbling using the process gas supplied from the process gas supply tank 63 and then supplies the sterilizing gas to the shower head 61 ). As the sterilization gas, hydrogen peroxide, alcohols, and the like may be used, but the present invention is not limited thereto.

The shower head 61 is installed inside the rotary chamber 20 and connected to the sterilizing gas bubbler 65. The showerhead 61 is elongated along the axial direction of the chamber tube 29, as shown in Figs. 2 and 4, and is disposed between the electrode tubes 53 in the form of a loop.

At this time, the electrode tube 53 is formed in a loop shape surrounding the shower head 61. The shower head 61 is positioned above the electrode tube 53 so as to inject the process gas and the sterilizing gas into the electrode tube 53.

The shower head 61 is provided with an injection port for injecting a process gas and a sterilizing gas into the electrode tube 53 side. The injection port may be formed with a slit having a width of 1 mm and may be sprayed around the electrode tube 53 at a flow rate of 20 to 100 sccm.

The AC power source 70 applies an AC voltage so as to generate a plasma by vacuum discharge based on the process gas supplied between the electrode tube 53 and the chamber tube 29. For example, the AC power source 70 may apply a middle frequency, RF or microwave AC voltage of 5 to 25 kV to the electrode tube 53 and the chamber tube 29.

On the other hand, the tubular electrode portion 50 and the gas supply line 62 of the gas supply portion 60 are installed in the first fixing flange 21 by the sealing assembly 80.

The first fixing flange 21 is formed with a mounting hole 22 through which the tubular electrode unit 50 and the gas supply line 62 can be fixedly installed in the rotary chamber 20. The sealing assembly 80 fixes the tubular electrode portion 50 and the gas supply line 62 to the mounting hole 22 while sealing the mounting hole 22.

The sealing assembly 80 includes a mounting plate 81, an insulating plate 83, an insulating pipe 85, a fastening member 86, and a vacuum o-ring 87. The mounting plate 81 is installed inside the rotary chamber 20 and has a size covering the mounting hole 22 and a tubular electrode unit 50 and a gas supply line 62 are provided. The insulating plate 83 is interposed between the mounting plate 81 and the first fixing flange 21 and has an insertion hole 84 through which the tubular electrode unit 50 and the gas supply line 62 are inserted. The column connection 85 is connected to the insertion hole 84 of the insulating plate 83 and extends through the mounting hole 22 to the outside of the first fixing flange 21, And the gas supply line 62 are protected. The fastening member 86 fixes the mounting plate 81 to the inner surface of the first fixing flange 21 via the insulating plate 83. [ The vacuum o-ring 87 is interposed between the mounting plate 81, the insulating plate 83 and the first fixing flange 21 and sealed.

In this case, the tubular electrode unit 50 provided on the mounting plate 81 is a refrigerant inlet pipe 51 and a refrigerant outlet pipe 55. The gas supply unit 60 installed in the mounting plate 81 is a gas supply line 62 connected to the shower head. A power supply line 71 connected to the AC power source 70 is connected to the refrigerant injection pipe 51 and the refrigerant discharge pipe 55 located outside the mounting plate 81.

The insulating plate 83 and the insulating pipe 85 are integrally formed, and both have an opened hat shape. The insulation plate 83 and the insulation bolt 85 are connected to the first fixing flange 21 in such a manner that the refrigerant injection pipe 51 and the refrigerant discharge pipe 55 provided in the mounting hole 22 of the first fixing flange 21 are mechanically Thereby preventing electrical shorts caused by contact. Teflon may be used as the material of the insulating plate 81 and the insulating connection 83, and other materials having good electrical insulation may be used.

The fastening member 86 and the vacuum o-ring 87 may also be made of an electrically insulating material.

The arrangement of the electrode tube 53 with respect to the chamber tube 29 for generating the vacuum plasma in the rotary chamber 20 will be described with reference to FIGS. 6 and 7. FIG. 6 and 7 are views for explaining the positions of the electrode tubes 53a and 53b with respect to the rotary chamber 20 for generating a vacuum plasma.

6, when the powdered food 90 is put into the chamber tube 29 of the stationary rotary chamber 20, the powdered food 90 is supplied to both sides of the vertical line drawn from the rotation axis O of the chamber tube 29 to the horizontal plane The powdery food 90 is uniformly distributed.

The distance d1 between the electrode tube 53a and the chamber tube 29 increases as the amount of the powdery food 90 injected into the chamber tube 29 increases Away. When the distance d1 between the electrode tube 53a and the chamber tube 29 is increased, the influence of the alternating electric field is reduced, so that plasma generation is difficult, and continuous plasma discharge is difficult.

On the other hand, the distance d2 between the electrode tube 53b and the chamber tube 29 becomes closer as the position of the electrode tube 53b moves away from the vertical line toward the boundary between the chamber tube 29 and the powdery food 90. The position of the electrode tube 53b toward the boundary portion between the chamber tube 29 and the powdered food 90 according to the increased powdered food 90 even if the amount of the powdered food 90 injected into the chamber tube 29 increases, The distance between the electrode tube 53b and the chamber tube 29 can be kept constant or at a distance necessary for plasma generation.

7, when the rotary chamber 20 is rotated, the powdery food 90 is distributed obliquely in the rotating direction of the rotary chamber 20. The surface 91 of the powdered food 90 forms a horizontal plane, for example, perpendicular to the vertical line, before the rotation chamber 20 rotates.

When the rotary chamber 20 is rotated in the counterclockwise direction in this state, the powdered food 90 forms a slope 93 having a high right side and a low left side with respect to a vertical line. The powdered food 90 which is distributed over the inclined face 93 moves downward along the inclined face 93 while the powdered food 90 is mixed with the inclined distributed powdery food 90 as the rotary chamber 20 rotates The powdery food 90 located below the inclined surface 93 is repeatedly exposed to the outside while moving to the top of the inclined surface 93 by the rotation of the rotary chamber 20. [

Therefore, it is preferable that the electrode tube 53c is disposed at a position spaced apart from a vertical line rather than being disposed on a vertical line. Even if the powdered food 90 rises in the direction of rotating on the inner circumferential surface of the chamber tube 29 in accordance with the rotation of the chamber tube 29, it can not rise up to the point where it is perpendicular (90 degrees) to the vertical line due to its own weight. Therefore, the electrode tube 53c can be installed at an angle? Within 90 degrees in the direction in which the chamber tube 29 rotates with respect to the vertical line. More preferably, the electrode tube 53c is disposed so as to be positioned at the uppermost portion of the inclined surface 93 formed by the powdered food 90 by the rotation of the chamber tube 29. By disposing the electrode tube 53c in this way, the distance between the electrode tube 53c and the chamber tube 29 required for plasma generation can be maintained.

Therefore, the powder sterilization apparatus according to the present embodiment is configured such that the angle of the sloped surface 93 formed by the powdered food 90 depends on the amount of the powdery food 90 to be supplied to the rotary chamber 20, It is possible to uniformly sterilize the powdery food 90 put into the rotary chamber 20 by using the plasma.

It should be noted that the embodiments disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

10: rotation part 20: rotation chamber
21: first fixing flange 22: mounting hole
23: second fixing flange 24a: first o-ring
24b: second O-ring 25: first rotation flange
27: second rotating flange 29: chamber tube
31: uneven 33: inner space
35: O-ring for vacuum 37: Bent valve
40: Vacuum pump 41: Exhaust line
43: opening / closing valve 45: vacuum gauge
47: temperature sensor 50: tubular electrode part
51: Refrigerant injection tube 53: Electrode tube
55: refrigerant discharge pipe 56: refrigerant circulation part
57: Refrigerant supply tank 58: Heat exchanger
60: gas supply unit 61: shower head
62: gas supply line 63: process gas supply tank
64: Flow meter 65: Sterilization gas bubbler
67: valve 70: AC power
71: power supply line 80: sealing assembly
81: mounting plate 83: insulating plate
84: insert hole 85: parcel connection
86: fastening member 87: o-ring for vacuum
90: Powdered food 100: Powdered food sterilizing device

Claims (8)

reel;
A rotary chamber into which the powdered food is introduced and which rotates the powdery food while being rotated by the rotary unit;
A vacuum pump connected to the rotary chamber for generating a vacuum in the rotary chamber;
A tubular electrode unit having an electrode tube fixedly installed in the rotary chamber and installed close to an inner circumferential surface of the rotary chamber to which the powdered food is injected and rotating, and having a tubular shape in which the refrigerant circulates into the electrode tube;
A gas supply unit fixedly installed in the rotary chamber, the gas supply unit having a shower head for supplying a process gas for plasma generation and sterilizing gas around the electrode tube;
And an AC voltage is applied between the electrode tube and the rotation chamber in a state where the rotation chamber is in a vacuum state to generate a plasma generated between the electrode tube and the inner peripheral surface of the rotation chamber based on the process gas supplied through the shower head and the sterilizing gas And an AC power source for sterilizing the powdered food in the rotating chamber,
The rotating chamber includes:
A pair of fixing flanges spaced apart from each other in a disk form and to which the tubular electrode portion and the gas supply portion are fixed;
A pair of rotation flanges rotatably coupled to the pair of fixing flanges in a ring shape while maintaining a vacuum state through a plurality of O-rings; And
Wherein the inner surface of the inner space is formed with uniform irregularities on the inner circumferential surface thereof and the powdered food is rolled while rotating together with the pair of rotation flanges, And a chamber tube electrically connected to the AC power source,
The tube-
A refrigerant inlet tube for receiving a refrigerant from the outside of the rotary chamber;
An electrode tube connected to the coolant injection tube and installed near the inner circumferential surface of the chamber tube through the fixing flange and generating a plasma by receiving an AC voltage; And
A refrigerant discharge pipe connected to the electrode tube to discharge the refrigerant out of the rotary chamber through the fixing flange;
Wherein the plasma sterilizer is a plasma sterilizer. delete delete The method according to claim 1,
Wherein the shower head of the gas supply unit is elongated along an axial direction of the chamber tube, and the electrode tube is formed in a loop shape surrounding the showerhead. The method according to claim 1,
Wherein one of the pair of fixing flanges is provided with a mounting hole for fixing the tubular electrode portion and the gas supply portion,
A sealing assembly for sealing the mounting hole and fixing the tubular electrode portion and the gas supply portion to the mounting hole;
Further comprising a plasma sterilizing device for sterilizing the powder. 6. The seal assembly of claim 5,
A mounting plate installed inside the rotating chamber and having a size to cover the mounting hole and having the tubular electrode portion and the gas supply portion;
An insulating plate interposed between the mounting plate and the fixing flange and having an insertion hole into which the tubular electrode portion and the gas supply portion are inserted;
A tubular electrode portion connected to the insertion hole of the insulating plate and drawn out of the fixing flange through the mounting hole to protect the tubular electrode portion and the gas supply portion;
A fastening member for fixing the mounting plate to the fixing flange via the insulating plate; And
A vacuum o-ring interposed between the mounting plate, the insulating plate, and the fixing flange;
Wherein the plasma sterilizer is a plasma sterilizer. The electrode assembly according to claim 1,
Wherein the chamber tube is disposed so as to form an angle of less than 90 degrees with a vertical line in a direction in which the chamber tube rotates with respect to a vertical line drawn from the rotation axis of the chamber tube to a horizontal plane. The method according to claim 1,
The rotation unit rotates the rotation chamber at 5 to 20 rpm,
The vacuum pump maintains the inside of the rotation chamber at 10 ^-2 to 10 ^-1 torr,
The AC power source applies a middle frequency, RF or microwave AC voltage of 5 to 25 kV,
Wherein the process gas comprises nitrogen, oxygen, argon or helium,
Wherein the sterilizing gas comprises hydrogen peroxide or alcohols.

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