Device and method for enhancing rapid sterilization of gas phase plasma on object surface

Abstract

The invention provides a device and a method for enhancing rapid sterilization of a gas phase plasma on an object surface, and relates to the field of low-temperature plasmas. Through an atomization device, an atomized solution containing Fe < 2 + >, Cu < 2 + > or Mn < 2 + > and a H2O2 solution are introduced near a plasma generator, transition metal ions are used as a catalyst, H2O2 can be activated, active oxygen-containing free radicals with strong oxidizing property are generated, the transition metal ions and other active species generated in plasma act on microorganisms on the surface of an object to be killed in a synergistic manner, and the surface of the object to be killed can be killed. And the plasma sterilization efficiency is obviously improved. The circulating air flow in the disinfection chamber can promote the to-be-activated gas in the chamber to be activated through the plasma reactor, and can also accelerate material exchange between the internal space of the disinfection chamber and the surface of the to-be-disinfected object, so that active species effectively act on microorganisms on the surface of the object, the inactivation efficiency of the microorganisms is improved, and the disinfection time is effectively shortened.

Description

Technical Field

[0001] The invention belongs to the field of low-temperature plasma sterilization, and specifically relates to a device and method for enhancing the rapid sterilization of an object surface by gas phase plasma. Background Art

[0002] In today's society, as people pay more and more attention to health and hygiene, efficient and safe sterilization technology has become a hot topic of research. As an emerging sterilization method, low-temperature plasma sterilization technology is gradually attracting widespread attention. Compared with traditional sterilization methods, atmospheric pressure low-temperature plasma sterilization technology has the advantages of environmental protection and safety, wide applicability, and simple operating conditions, and has shown broad application prospects in surface disinfection. By utilizing the active particles in the plasma to interact with the surface of the object, this technology can effectively kill microorganisms, and at the same time, the original quality of the object can be maintained after disinfection. Therefore, low-temperature plasma sterilization technology has a high promotion value and will provide strong support for the development of food safety, public health and other fields. However, compared with some sterilization methods, such as ultra-high temperature sterilization (UHP) and ultra-high temperature sterilization (UHT), which only take tens of seconds or even more than ten seconds to complete the sterilization, the conventional air plasma sterilization process is relatively slow. For example, for the sterilization of a flat plastic culture dish, it may only take a few minutes at a high power, and about 3-5 minutes can achieve a good sterilization effect. At low power, it may take 15-30 minutes, or even longer. In actual application scenarios, such as when a large number of medical devices need to be processed quickly or in emergency food processing sterilization, where high sterilization speed is required, its speed disadvantage is more obvious. Therefore, improving the disinfection efficiency of plasma and shortening the disinfection time can improve production efficiency and reduce the burden on staff. How to more effectively disinfect the surfaces of various objects and put this technology into actual production still needs to be studied. Summary of the invention

[0003] Based on the above background, the present invention proposes a device and method for enhancing the rapid sterilization of surfaces by gas-phase plasma. Through the technical means mentioned in the present invention, the disinfection time of surfaces by plasma can be greatly shortened, the production efficiency of enterprises can be improved, and continuous processing and industrial scale-up applications can be facilitated.

[0004] The technical means adopted by the present invention are as follows:

[0005] A device for enhancing rapid sterilization of an object surface by gas phase plasma, comprising a sterilization chamber and an atomization device, wherein the sterilization chamber is connected to the atomization device;

[0006] The disinfection chamber is provided with a plasma generator and a fan, and the plasma reactor is located above the fan;

[0007] The atomization device includes a liquid storage tank and a mist inlet pipe, wherein the liquid storage tank is connected to the disinfection chamber through the mist inlet pipe; an atomizer is arranged in the liquid storage tank, and the liquid storage tank includes a salt solution storage tank and an H2O2 storage tank, and the salt solution storage tank is filled with Fe 2+ , Cu 2+ or Mn 2+ The H2O2 storage tank is filled with a salt solution.

[0008] Preferably, the disinfection chamber is welded from steel plates, the steel plates are 304 stainless steel plates, and the thickness of the steel plates is 2-3 mm. Specifically, the disinfection chamber is welded from 304 stainless steel plates with a thickness of 2-3 mm, and the size of the disinfection chamber is 700 mm×500 mm×500 mm.

[0009] Preferably, the disinfection chamber is provided with an air inlet and an air outlet, the air inlet is connected to the mist inlet pipe, and the air outlet is connected to the tail gas treatment device, which does not actively extract the gas in the chamber, but only extracts the gas naturally overflowing from the chamber to prevent environmental pollution. The air inlet is circular with a diameter of 10-20mm; the air outlet is circular with a diameter of 20-40mm. The size of the sample delivery port can be adjusted according to the size of the object to be disinfected.

[0010] Preferably, the air inlet and the air outlet should be arranged on opposite sides of the disinfection chamber, with the air inlet 20-50 mm away from the top of the disinfection chamber, and the air outlet 20-50 mm away from the bottom of the disinfection chamber.

[0011] Preferably, the plasma generator is fixed to the top of the disinfection chamber by screws, and the screws are polyethylene tetrafluoro screws.

[0012] Preferably, the plasma generator structure is a device such as surface dielectric barrier discharge, dielectric barrier discharge, sliding arc discharge, corona discharge, etc., which is the existing technology in the field.

[0013] Preferably, the plasma generator is connected to a power supply, and the power supply is a high-voltage AC power supply or a pulse power supply. The high-voltage AC power supply or the pulse power supply is used to power the plasma generator, and the power input power is 1000-1200W.

[0014] Preferably, the liquid storage tank is made of stainless steel, such as 304 stainless steel or 316 stainless steel. The liquid storage tank is a cylinder with a bottom diameter of 150 mm and a height of 250 mm.

[0015] Preferably, the salt solution is a solution of 0.05mol / L-1mol / L Fe(NO3)2, CuCl2 or MnSO4, and the H2O2 solution is a H2O2 solution with a mass fraction of 15%-30%. For example, the salt solution storage tank contains 500ml of salt solution, and the H2O2 storage tank contains 500ml of H2O2 solution.

[0016] Preferably, the liquid storage tank is provided with an air inlet and an air outlet, the air inlet is connected to air or compressed air, air or compressed air enters the liquid storage tank at the air inlet, and the air outlet of the liquid storage tank is connected to the mist inlet pipe, so that the atomized solution can pass into the mist inlet pipe and then into the disinfection chamber; the air intake volume of the salt solution storage tank is 0.5-1L / min, and the air intake volume of the H2O2 storage tank is 5-7L / min.

[0017] Preferably, the height difference between the liquid storage tank and the air inlet of the disinfection chamber should ensure that the solution condensed on the mist inlet pipe can naturally flow back into the liquid storage tank to avoid clogging the mist inlet pipe.

[0018] Preferably, the mist inlet pipe is made of polyethylene, polyvinyl chloride, polyethylene tetrafluoroethylene or rubber. The length of the mist inlet pipe between each liquid storage tank and the disinfection chamber is 1-3m, and the diameter of the mist inlet pipe is 5-20mm.

[0019] Preferably, the fan is an axial flow fan, such as a 304 stainless steel axial flow fan; the fan has an operating voltage of 24V or 12V, and an air volume of 100-150m 3 / h.

[0020] Preferably, the fan is provided with a fan bracket for fixing the fan, and the fan is fixed to the fan bracket by using stainless steel screws through fixing holes on the fan.

[0021] Preferably, the fan is located at the upper and lower parts of the disinfection chamber, and is divided into an upper fan and a lower fan. The upper fan is 10 mm to 30 mm away from the plasma generator, and the wind direction is downward. The lower fan is at the lower part of the disinfection chamber, 20 mm to 50 mm away from the chamber bottom plate, and the wind direction is upward. The arrangement of the fan should ensure the circulation of the active gas in the disinfection chamber.

[0022] Preferably, a structure for placing objects to be disinfected is provided in the disinfection chamber. Depending on the type of objects to be disinfected, the internal structure of the sterilization device should be appropriately adjusted to achieve disinfection of specific types of samples. For example, the structure for placing objects to be disinfected is a tray, a gas duct or a transmission device. When the structure for placing samples to be disinfected is a tray, the disinfection chamber is provided with a sample delivery port, a tray is provided at the sample delivery port, a plurality of through holes are provided on the tray, and the tray is movably connected to the sample delivery port; a tray handle is provided at one end of the tray. The tray is made of stainless steel. The tray is placed in the lower middle part of the disinfection chamber 1, 100 mm away from the bottom of the disinfection chamber 1, and can slide left and right by pulling the tray handle. The objects to be disinfected are placed on the tray. When the structure for placing samples to be disinfected is a gas duct, a gas duct is provided below the bottom of the upper fan, and the gas duct is connected to the upper fan; the gas duct includes an upper hollow step and a lower rectangular parallelepiped structure, each side of the lower part of the gas duct is provided with a through hole, and a through hole is provided at the bottom. There are multiple through holes, for example 3-4. The disinfection chamber is provided with a sample delivery port, and the object to be disinfected is delivered into the disinfection chamber through the sample delivery port. The gas conduit is made of stainless steel

[0023] When the sample placement structure for disinfection is a transmission device, the object to be disinfected is sent into the disinfection chamber through the transmission device, and the disinfection time is controlled by the speed of the transmission device.

[0024] The method for sterilization using the above device comprises the following steps:

[0025] Start the plasma generator and the fan, then turn on the atomization device, wait until the temperature in the disinfection chamber reaches a stable level, send the object to be disinfected into the disinfection chamber, take it out after a certain period of treatment, and the microorganisms on the surface of the object can be quickly disinfected.

[0026] Preferably, the temperature for disinfecting the object to be disinfected is 50°C-100°C, preferably 60°C-90°C, more preferably 80°C-85°C, and the treatment time is 10 to 30 seconds.

[0027] Preferably, when the fan is running, the gas flow rate on the surface of the object should be controlled to be 2-4 m / s.

[0028] Preferably, the object is a medical supply, a beverage bottle or a packaging material, the medical supply is a thermometer, a stethoscope, a breathing bag, etc., the beverage bottle can be made of PET plastic, HDPE plastic, tinplate, etc., and the packaging material is a paper packaging material.

[0029] Transition metal ions (such as Fe, Cu, Co, Mn, Ce, Ag) have multiple valence states. In the process of reacting with H2O2, both transition metal ions and H2O2 can play the dual role of oxidant and reductant, producing active oxygen-containing free radicals with strong oxidizing properties. Plasma can produce active species such as H2O2, hydroxyl radicals, singlet oxygen, and peroxynitrite during the discharge process. The synergistic effect of transition metal ion salt solution and plasma on surface disinfection may greatly improve the inactivation efficiency of plasma on microorganisms.

[0030] Compared with the prior art, the present invention provides a method for enhancing the rapid sterilization of the surface of an object by gas phase plasma. 2+ , Cu 2+ or Mn 2+ The solution and H2O2 solution are introduced into the vicinity of the plasma generator, and the disinfection chamber is high temperature and high humidity (temperature greater than 50°C, humidity greater than 10g / m 3 ) environment, the plasma-activated mist condenses an extremely thin water layer on the surface of the object at room temperature. In the water layer, transition metal ions act as catalysts to activate H2O2 and produce active oxygen-containing free radicals with strong oxidizing properties. They synergize with other active species generated by the plasma to act on the microorganisms on the surface of the object, significantly improving the plasma sterilization efficiency. The circulating airflow in the disinfection chamber can not only promote the activation of the gas to be activated in the chamber through the plasma reactor, but also accelerate the material exchange between the internal space of the disinfection chamber and the surface of the object to be disinfected, so that the active species can effectively act on the microorganisms on the surface of the object, improve the inactivation efficiency of microorganisms, and effectively shorten the disinfection time. Through these characteristics, the plasma processing time can be greatly shortened, making the technology easy to continuously process and industrially scale up. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the overall structure of the device of Example 1 provided by the present invention.

[0033] Figure 3 This is a three-dimensional diagram of the tray.

[0034] Figure 4 This is a demonstration of the sterilization effect of the device in Example 1. From left to right, it corresponds to the bacteria sheets at the left, middle and right positions in the tray.

[0035] Figure 5 The overall structural diagram of the device of Example 2 provided by the present invention,

[0036] Figure 6 This is a three-dimensional diagram of the gas duct.

[0037] Figure 7 This is a demonstration of the plasma sterilization effect of the device in Example 2. From left to right, it corresponds to the bacteria sheets on the top, middle and bottom of the beverage bottle.

[0038] Figure 8 This is a schematic diagram of the overall structure of the device of Example 3 provided by the present invention.

[0039] Fig. 9 This is a demonstration of the plasma sterilization effect of the device in Example 3. From left to right, the bacterial sheets at the left, middle and right positions of the packaging material are shown.

[0040] Legend: 1 disinfection chamber, 2 air outlet, 3 air inlet, 4 plasma generator, 5 upper fan, 6 lower fan, 7 fan bracket, 8 salt solution storage tank, 9 H2O2 storage tank, 10 mist inlet pipe, 11 tray handle, 12 tray, 13 gas duct, 14 beverage bottle, 15 packaging material, 16 roller. DETAILED DESCRIPTION

[0041] The following non-limiting embodiments may enable a person skilled in the art to more fully understand the present invention, but are not intended to limit the present invention in any way.

[0042] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "upper left, upper right, lower left, lower right, directly below, directly above" and "top, bottom", etc. are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0043] Example 1

[0044] like Figure 1-3 As shown, a device for enhancing the rapid sterilization of diagnostic and therapeutic supplies by gas phase plasma includes a disinfection chamber 1 and an atomization device, and the disinfection chamber 1 is connected to the atomization device.

[0045] The disinfection chamber 1 is a closed structure, welded from 2mm stainless steel plates, and the size of the disinfection chamber 1 is 700mm×400mm×400mm. An air inlet 3 is set on the upper right plate of the disinfection chamber 1, and the air inlet 3 is connected to the mist inlet pipe 10. The size of the air inlet 3 is a circle with a diameter of 15mm, and it is 30mm away from the top of the disinfection chamber 1; an air outlet 2 is set on the lower left plate of the disinfection chamber 1, and the size of the air outlet 2 is a circle with a diameter of 20mm, and it is 30mm away from the bottom of the disinfection chamber 1. An exhaust gas treatment device is set outside the air outlet 2, and the exhaust gas treatment device is connected to the air outlet 2. The exhaust gas treatment device does not actively extract the gas in the disinfection chamber 1, but only extracts the gas naturally overflowed from the disinfection chamber 1 to prevent environmental pollution.

[0046] A plasma generator 4 is provided in the disinfection chamber 1, and the plasma generator 4 is fixed to the top of the disinfection chamber 1 by polyethylene tetrafluoroethylene screws. The structure of the plasma generator 4 is a surface dielectric barrier discharge, the high-voltage electrode is a stainless steel plate, the ground electrode is a stainless steel mesh, and the dielectric plate is a ceramic. A high-voltage AC power supply is used to power the plasma generator 4, and the power input power is 700W.

[0047] The atomizing device includes a salt solution storage tank 8, an H2O2 storage tank 9 and a mist inlet pipe 10, and the salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the disinfection chamber 1 through the mist inlet pipe 10. The salt solution storage tank 8 and the H2O2 storage tank 9 are arranged on the right side of the disinfection chamber 1. The salt solution storage tank 8 and the H2O2 storage tank 9 are made of 304 stainless steel. The salt solution storage tank 8 and the H2O2 storage tank 9 are cylinders with a bottom diameter of 150mm and a height of 250mm. The salt solution storage tank 8 is filled with 500ml of 0.05mol / LFeCl2 solution, and the H2O2 storage tank 9 is filled with 500ml of 30% H2O2 solution. The salt solution storage tank 8 and the H2O2 storage tank 9 are each provided with an atomizer. The salt solution storage tank 8 and the H2O2 storage tank 9 are both provided with an air inlet and an air outlet. The air inlet is connected to compressed air. Compressed air is passed into the salt solution storage tank 8 and the H2O2 storage tank 9 at the air inlet. The air outlets of the salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the mist inlet pipe 10, so that the atomized solution can be passed into the mist inlet pipe 10. The air intake of the salt solution storage tank 8 is 1L / min. The air intake of the H2O2 storage tank 9 is 7L / min. The mist inlet pipe 10 is made of polyethylene tetrafluoroethylene and has a diameter of 15mm. The length of the mist inlet pipe 10 between the salt solution storage tank 8 and the disinfection chamber 1 is about 2m, and the length of the mist inlet pipe 10 between the H2O2 storage tank 9 and the disinfection chamber 1 is about 2.5m. The atomized solution in the salt solution storage tank 8 is passed into the vicinity of the plasma generator 4 through the mist inlet pipe 10.

[0048] A fan is provided below the plasma reactor 4, an upper fan 5 is provided above the disinfection chamber 1, and a lower fan 6 is provided below the disinfection chamber 1. Both the upper fan 5 and the lower fan 6 are 304 stainless steel axial flow fans, with an operating voltage of 24V, a fan side length of 40mm, and an air volume of 100m 3 / h. The fan is fixed to the fan bracket 7 with stainless steel screws through the fixing holes on the fan. The upper fan 5 is located at the upper rear of the disinfection chamber 1, 20 mm away from the plasma generator 4, with the wind direction facing downward; the lower fan 6 is located at the lower front of the disinfection chamber 1, 50 mm away from the bottom of the disinfection chamber 1.

[0049] The disinfection chamber 1 is provided with a disinfection object placement structure, which is a tray 12. A sample delivery port is provided above the air outlet 2 of the disinfection chamber 1, and a tray 11 is provided at the sample delivery port. The tray 12 is made of stainless steel and has a size of 600*400*2mm. There are several openings on the tray 12 with an area of ​​about 5cm 2 The tray 12 is movably connected to the sample delivery port. A tray handle 1 is welded on one side of the tray. The tray 12 is placed in the lower middle part of the disinfection chamber 1 through a guide rail, 100 mm away from the bottom of the disinfection chamber 1, and can be slid left and right by pulling out the tray handle 11. The wind speed at the tray is about 3 m / s. The object to be disinfected is placed on the tray 11.

[0050] The method for sterilization using the above device comprises the following steps:

[0051] Start the plasma generator 4, the upper fan 5 and the lower fan 6, and then turn on the atomizer. After about 1 hour, the temperature in the disinfection chamber 1 stabilizes to 60°C. Pull the tray handle 11, pull out the tray 12, place the medical supplies to be disinfected (thermometer, stethoscope, breathing bag, etc.) on the tray 12, push the tray 12 into the disinfection chamber 1, and process for 20 seconds to disinfect the medical supplies.

[0052] The bactericidal test method is: take 10 μl of the concentration of 5×10 7The bacterial liquid of Bacillus subtilis var. subtilis (ATCC9372) with CFU / ml was dropped on a 10mm×10mm stainless steel sheet and dried in a 37℃ incubator for 10 minutes to make a bacterial sheet. When the temperature of the disinfection chamber 1 stabilizes to 60℃, at the beginning of each experiment, the tray handle 11 is pulled to pull out the tray 12, and the bacterial sheet is attached to the left, middle and right positions of the tray respectively. The tray 12 is sent into the disinfection chamber 1 for treatment for 20 seconds, and then the bacterial sheet is recovered into 2ml sterile water. After ultrasonication for 10 minutes, 300μl is taken and coated on the culture dish, and cultured at 37℃ for 24 hours. This experiment was divided into four groups. The first group used air plasma without introducing additional aerosol into the sterilization chamber 1. The second group used H2O2 plasma alone and introduced only atomized H2O2 solution into the sterilization chamber 1. The third group used FeCl2 plasma alone and introduced only atomized FeCl2 solution into the sterilization chamber 1. The fourth group used H2O2+FeCl2 plasma and introduced atomized H2O2 and FeCl2 solutions into the sterilization chamber 1 at the same time. Figure 4 As shown, the experimental results show that, with the same treatment for 20s, all the subtilis spores were inactivated only in the fourth group using H2O2+FeCl2 plasma, while when using H2O2 plasma or FeCl2 plasma alone, the number of subtilis spores in the recovered sample was about 2 orders of magnitude, and when using air plasma, the number of subtilis spores in the recovered sample was about 3 orders of magnitude.

[0053] Example 2

[0054] like Figure 1 , 5 As shown in 6, a device for enhancing the rapid sterilization of beverage bottles by gas-phase plasma includes a disinfection chamber 1 and an atomization device, and the disinfection chamber 1 is connected to the atomization device. The disinfection chamber 1 is a closed structure, welded from a 2mm stainless steel plate, and the size of the disinfection chamber 1 is 700mm×500mm×500mm. An air inlet 3 is arranged on the upper right plate of the disinfection chamber 1, and the air inlet 3 is connected to the mist inlet pipe 10. The size of the air inlet 3 is a circle with a diameter of 15mm, and it is 30mm away from the top of the disinfection chamber 1; an air outlet 2 is arranged on the lower left plate of the disinfection chamber 1, and the size of the air outlet 2 is a circle with a diameter of 20mm, and it is 30mm away from the bottom of the disinfection chamber 1. An exhaust gas treatment device is arranged outside the air outlet 2, and the exhaust gas treatment device is connected to the air outlet 2. The exhaust gas treatment device does not actively extract the gas in the disinfection chamber 1, but only extracts the gas naturally overflowing from the disinfection chamber 1 to prevent environmental pollution.

[0055] A plasma generator 4 is provided in the disinfection chamber 1, and the plasma generator 4 is fixed to the top of the disinfection chamber 1 by polyethylene tetrafluoroethylene screws. The structure of the plasma generator 4 is a surface dielectric barrier discharge, the high-voltage electrode is a stainless steel plate, the ground electrode is a stainless steel mesh, and the dielectric plate is a ceramic. A high-voltage AC power supply is used to power the plasma generator 4, and the power input power is 1000W.

[0056] The atomizing device includes a FeCl2 storage tank 8, a H2O2 storage tank 9 and a mist inlet pipe 10. The salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the disinfection chamber 1 through the mist inlet pipe 10. The salt solution storage tank 8 and the H2O2 storage tank 9 are arranged on the right side of the disinfection chamber 1. The salt solution storage tank 8 and the H2O2 storage tank 9 are made of 304 stainless steel. The salt solution storage tank 8 and the H2O2 storage tank 9 are cylinders with a bottom diameter of 150mm and a height of 250mm. The salt solution storage tank 8 is filled with 500ml of 0.05mol / LFeCl2 solution, and the H2O2 storage tank 9 is filled with 500ml of 30% H2O2 solution. The salt solution storage tank 8 and the H2O2 storage tank 9 are each provided with an atomizer. The salt solution storage tank 8 and the H2O2 storage tank 9 are both provided with an air inlet and an air outlet. The air inlet is connected to compressed air. Compressed air is passed into the salt solution storage tank 8 and the H2O2 storage tank 9 at the air inlet. The air outlets of the salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the mist inlet pipe 10, so that the atomized solution can pass into the mist inlet pipe 10. The air intake of the salt solution storage tank 8 is 1L / min. The air intake of the H2O2 storage tank 9 is 7L / min. The mist inlet pipe 10 is made of polyethylene tetrafluoroethylene and has a diameter of 15mm. The length of the mist inlet pipe 10 between the salt solution storage tank 8 and the disinfection chamber 1 is about 2m, and the length of the mist inlet pipe 10 between the H2O2 storage tank 9 and the disinfection chamber 1 is about 2.5m. The atomized solution in the salt solution storage tank 8 is passed into the vicinity of the plasma generator 4 through the mist inlet pipe 10.

[0057] A fan is provided below the plasma reactor 4, an upper fan 5 is provided above the disinfection chamber, and a lower fan 6 is provided below the disinfection chamber 1. Both the upper fan 5 and the lower fan 6 are 304 stainless steel axial flow fans, with an operating voltage of 24V and a fan side length of 40mm; air volume 100m 3 / h. The fan is fixed to the fan bracket 7 with stainless steel screws through the fixing holes on the fan. The upper fan 5 is located at the upper rear of the disinfection chamber 1, 20 mm away from the plasma generator 4, with the wind direction facing downward, and the lower fan 6 is located at the lower front of the disinfection chamber 1, 50 mm away from the bottom of the disinfection chamber 1.

[0058] The disinfection chamber 1 is provided with a disinfection object placement structure, which is a gas duct 13. A gas duct 11 is provided below the bottom of the upper fan 5, and the gas duct 13 is connected to the upper fan 11. The top of the gas duct 11 is aligned with the bottom of the upper fan 5 in the longitudinal direction and fits tightly. The wall of the gas duct 13 is made of 304 stainless steel, 1mm thick, including an upper hollow step and a lower rectangular parallelepiped structure. The dimensions of the upper hollow step are: upper bottom 40mm×40mm, lower bottom 10mm×10mm, and height 25mm; the dimensions of the lower rectangular parallelepiped are: length 10mm, width 10mm, height 150mm, and 3 small holes with a diameter of 4mm are opened on each of the four sides of the lower part of the gas duct 13, and 4 small holes with a diameter of 4mm are set at the bottom. According to measurement, when the upper fan 5 is running, the wind speed at the bottom of the gas duct 13 reaches 3m / s. The disinfection chamber 1 is provided with a sample delivery port, and the object to be disinfected is delivered into the disinfection chamber 1 through the sample delivery port.

[0059] The method for sterilization using the above device comprises the following steps:

[0060] Start the plasma generator 4, the upper fan 5 and the lower fan 6, and then turn on the atomization device. After about 1 hour, the temperature in the disinfection chamber 1 stabilizes to 82°C. Use a long-handled steel clamp to clamp the beverage bottle, send the beverage bottle 14 into the disinfection chamber 1, align the bottle mouth with the gas duct 11, and insert the gas duct 11 into the lower middle part of the beverage bottle. Then keep the beverage bottle still and treat it for 10 seconds to disinfect the inside of the beverage bottle.

[0061] The sterilization test method is as follows: a PET beverage bottle 14 is sterilized with medical alcohol and dried. Take 10 μl of a concentration of 5×10 7 CFU / ml of bacterial liquid of Bacillus subtilis var. subtilis (ATCC9372) is dropped onto a 10mm×10mm bottle piece, dried in a 37°C incubator for 10 minutes to make a bacterial slice. When the temperature of the sterilization chamber 1 stabilizes to 82°C, three bacterial slices are taken and respectively attached to the top, middle and bottom of the beverage bottle. The beverage bottle is clamped with a long-handled steel clamp and sent into the sterilization chamber 1. The bottle mouth is aligned with the gas duct 11, and the gas duct 11 is inserted into the beverage bottle 14. The distance between the bottom of the gas duct 11 and the bottom of the beverage bottle 14 is controlled to be 10mm, and then the beverage bottle remains stationary for 10 seconds. After that, the bacterial slice is recovered into 2ml of sterile water. After 10 minutes of ultrasonication, 300μl is taken and spread on the culture dish and cultured at 37°C for 24 hours. Figure 7 As shown, the experimental results show that after 10 seconds of plasma treatment, all the subtilis spores on the surface of the bottle pieces were inactivated.

[0062] Example 3

[0063] like Figure 1 , 8As shown, a device for enhancing the rapid sterilization of packaging materials by gas phase plasma includes a disinfection chamber 1 and an atomization device, wherein the disinfection chamber 1 is connected to the atomization device.

[0064] The disinfection chamber 1 is a closed structure, welded from 2mm stainless steel plates, and the size of the disinfection chamber 1 is 2000mm×200mm×200mm. An air inlet 3 is set on the upper right plate of the disinfection chamber 1, and the air inlet 3 is connected to the mist inlet pipe 10. The size of the air inlet 3 is a circle with a diameter of 15mm, and it is 30mm away from the top of the disinfection chamber 1; the air outlet 2 is set at the lower left plate of the disinfection chamber 1, and the size of the air outlet 2 is a circle with a diameter of 20mm, and it is 30mm away from the bottom of the disinfection chamber 1. An exhaust gas treatment device is set outside the air outlet 2, and the exhaust gas treatment device is connected to the air outlet 2. The exhaust gas treatment device does not actively extract the gas in the disinfection chamber 1, but only extracts the gas naturally overflowed from the disinfection chamber 1 to prevent environmental pollution.

[0065] A plasma generator 4 is provided in the disinfection chamber 1, and the plasma generator 4 is fixed to the top of the disinfection chamber by polyethylene tetrafluoroethylene screws. The structure of the plasma generator 4 is a surface dielectric barrier discharge, the high-voltage electrode is a stainless steel plate, the ground electrode is a stainless steel mesh, and the dielectric plate is a ceramic. A high-voltage AC power supply is used to power the plasma generator 4, and the power input power is 700W.

[0066] The atomizing device includes a salt solution storage tank 8, an H2O2 storage tank 9 and a mist inlet pipe 10, and the salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the disinfection chamber 1 through the mist inlet pipe 10. The salt solution storage tank 8 and the H2O2 storage tank 9 are arranged on the right side of the disinfection chamber 1, and the salt solution storage tank 8 and the H2O2 storage tank 9 are made of 304 stainless steel. The salt solution storage tank 8 and the H2O2 storage tank 9 are cylinders with a bottom diameter of 150mm and a height of 250mm. The salt solution storage tank 8 and the H2O2 storage tank 9 are each provided with an atomizer. The salt solution storage tank 8 is filled with 500ml of 0.1mol / L Fe(NO3)2 solution, and the H2O2 storage tank 9 is filled with 500ml of 30% H2O2 solution. The salt solution storage tank 8 and the H2O2 storage tank 9 are both provided with an air inlet and an air outlet. The air inlet is connected to compressed air. Compressed air is passed into the salt solution storage tank 8 and the H2O2 storage tank 9 at the air inlet. The air outlets of the salt solution storage tank 8 and the H2O2 storage tank 9 are connected to the mist inlet pipe 10, so that the atomized solution can pass into the mist inlet pipe 10. The air intake of the salt solution storage tank 8 is 1L / min. The air intake of the H2O2 storage tank 9 is 7L / min. The mist inlet pipe 10 is made of polyethylene tetrafluoroethylene and has a diameter of 15mm. The length of the mist inlet pipe 10 between the salt solution storage tank 8 and the disinfection chamber 1 is about 2m, and the length of the mist inlet pipe 10 between the H2O2 storage tank 9 and the disinfection chamber 1 is about 2.5m. The atomized solution in the salt solution storage tank 8 is passed into the vicinity of the plasma generator 4 through the mist inlet pipe 10.

[0067] A fan is provided below the plasma reactor 4, an upper fan 5 is provided above the disinfection chamber 1, and a lower fan 6 is provided below the disinfection chamber 1. Both the upper fan 5 and the lower fan 6 are 304 stainless steel axial flow fans, with an operating voltage of 24V, a fan side length of 40mm, and an air volume of 100m 3 / h. Use stainless steel screws to fix it to the fan bracket 7 through the fixing holes on the fan. The upper fan 5 is located at the upper rear of the disinfection chamber 1, 20mm away from the plasma generator 4, and the wind direction is downward; the lower fan is located at the lower front of the disinfection chamber 1, 50mm away from the bottom of the disinfection chamber 1. When the disinfection device is in operation, the wind speed on the surface of the packaging material is about 3m / s.

[0068] The disinfection chamber 1 is provided with a disinfection object placement structure, which is a transmission device. The disinfection chamber 1 is provided with a sample delivery port, and the packaging material enters and exits the disinfection chamber 1 from the sample delivery port through the transmission device and the roller.

[0069] The method for sterilization using the above device comprises the following steps:

[0070] Start the plasma generator 4, the upper fan 5 and the lower fan 6, and then turn on the atomizer. After about 1 hour, the temperature in the disinfection chamber stabilizes to 76°C. Start the packaging material (paper packaging material 15) transmission device to disinfect the packaging material 11. The disinfection time is controlled by the speed of the transmission device.

[0071] The sterilization test method is as follows: cut the packaging material 15 into 10×10 mm pieces and sterilize them under ultraviolet light for 2 hours. Take 10 μl of 5×10 7 CFU / ml of Bacillus subtilis var. subtilis black (ATCC9372) bacterial liquid was dropped onto the packaging material 15, dried in a 37°C incubator for 10 minutes to make a bacterial sheet, and when the temperature of the disinfection chamber 1 stabilized to 76°C, the bacterial sheet was attached to the surface of the packaging material 15, and the transmission device was started to transfer the bacterial sheet into the disinfection chamber 1. After about 20 seconds, the bacterial sheet was transferred out and recovered into 2 ml of sterile water. After ultrasonication for 10 minutes, 300 μl was taken and coated on the culture dish, and cultured at 37°C for 24 hours. Fig. 9 As shown, the experimental results show that after 20s of plasma treatment, all the Bacillus subtilis spores on the surface of 15 packaging materials were inactivated.

[0072] The above embodiments are only used to illustrate the technical solution of the present invention, and are not intended to limit it. Those skilled in the art should understand that changes and improvements to the present invention, or replacement of some of the technical features thereof, are still within the effective protection scope of the technical solution of the present invention.

Claims

1. A device for enhancing the rapid sterilization of surfaces by low-temperature plasma, characterized in that: It includes a disinfection chamber and an atomization device, wherein the disinfection chamber is connected to the atomization device; The disinfection chamber is provided with a plasma generator and a fan, and the plasma reactor is located above the fan; The atomization device includes a liquid storage tank and a mist inlet pipe, wherein the liquid storage tank is connected to the disinfection chamber through the mist inlet pipe; an atomizer is arranged in the liquid storage tank, and the liquid storage tank includes a salt solution storage tank and an H2O2 storage tank, and the salt solution storage tank is filled with Fe 2+ , Cu 2+ or Mn 2+ The H2O2 storage tank is filled with a salt solution.

2. The device according to claim 1, characterized in that The disinfection chamber is provided with an air inlet and an air outlet, wherein the air inlet is connected to the mist inlet pipe, and the air outlet is connected to the tail gas treatment device.

3. The device according to claim 2, characterized in that The air inlet is circular with a diameter of 10-20 mm; the air outlet is circular with a diameter of 20-40 mm; the air inlet and the air outlet are arranged on opposite sides of the disinfection chamber, the air inlet is 20-50 mm away from the top of the disinfection chamber, and the air outlet is 20-50 mm away from the bottom of the disinfection chamber.

4. The device according to claim 1, characterized in that The plasma generator is a surface dielectric barrier discharge, dielectric barrier discharge, sliding arc discharge or corona discharge device; the plasma generator is connected to a power supply, and the power supply is a high-voltage AC power supply or a pulse power supply.

5. The device according to claim 1, characterized in that The salt solution is a solution of 0.05mol / L-1mol / L Fe(NO3)2, CuCl2 or MnSO4, and the H2O2 solution is a H2O2 solution with a mass fraction of 15%-30%.

6. The device according to claim 1, characterized in that The liquid storage tank is provided with an air inlet and an air outlet, and the air inlet is connected to air or compressed air; the air intake volume of the salt solution liquid storage tank is 0.5-1L / min, and the air intake volume of the H2O2 liquid storage tank is 5-7L / min.

7. The device according to claim 1, characterized in that The disinfection chamber is welded from steel plates; the liquid storage tank is made of stainless steel; the plasma generator is fixed to the top of the disinfection chamber by screws, and the screws are polyethylene tetrafluoro screws; the mist inlet pipe is made of polyethylene, polyvinyl chloride, polyethylene tetrafluoro or rubber; the length of the mist inlet pipe between each liquid storage tank and the disinfection chamber is 1-3m, and the diameter of the mist inlet pipe is 5-20mm.

8. The device according to claim 1, characterized in that The fan is provided with a fan bracket for fixing the fan; the fan is located at the upper and lower parts of the disinfection chamber, and is divided into an upper fan and a lower fan, the distance between the upper fan and the plasma generator is 10mm-30mm, and the wind direction is downward; the lower fan is at the lower part of the disinfection chamber, the distance from the chamber bottom plate is 20-50mm, and the wind direction is upward; a disinfection object placement structure is provided in the disinfection chamber.

9. A method for sterilizing using the device according to any one of claims 1 to 8, characterized in that: The steps include: Start the plasma generator and the fan. After the plasma generator discharges stably, turn on the atomization device. When the gas temperature in the disinfection chamber reaches a stable level, send the object to be disinfected into the disinfection chamber. After a certain period of treatment, take it out to quickly disinfect the microorganisms on the surface of the object.

10. The method according to claim 9, characterized in that The temperature for disinfection of objects to be disinfected is 50-100℃, and the time is 10 to 30 seconds; when the fan is running, the gas flow rate on the surface of the object should be controlled at 2-4m / s.

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