Hydrogen peroxide low-temperature vaporization generator and vaporized hydrogen peroxide sterilization system

Abstract

The application discloses a hydrogen peroxide low-temperature vaporization generator and a vaporized hydrogen peroxide sterilization system. The hydrogen peroxide vaporization generator comprises a carrier gas inlet unit and a hydrogen peroxide vaporization unit, and a micro-mist nozzle is arranged in the hydrogen peroxide vaporization unit. The vaporized hydrogen peroxide sterilization system comprises the hydrogen peroxide vaporization generator and a space to be sterilized connected with the gas outlet of the hydrogen peroxide vaporization generator through a conveying pipeline; a pipe wall temperature monitoring sensor is arranged on the conveying pipeline, and a PTFE coating is coated on the inner wall; a hydrogen peroxide sensor is arranged in the space to be sterilized. The liquid film low-temperature vaporization technology is used, so that the decomposition of hydrogen peroxide in the vaporization process is reduced; the pipe wall temperature monitoring sensor is arranged on the conveying pipeline, and the PTFE coating is coated on the inner wall, so that the condensation and decomposition of hydrogen peroxide in the transportation process are reduced; and the carrier gas temperature, flow and humidity are dynamically adjusted, so that the sterilization stability is improved.

Description

Technical Field

[0001] This invention relates to the field of sterilization equipment technology, and in particular to a low-temperature hydrogen peroxide vaporization generator and a vaporized hydrogen peroxide sterilization system. Background Technology

[0002] Vaporized hydrogen peroxide sterilization utilizes the advantage that hydrogen peroxide in its gaseous state is more effective at killing bacterial spores than in its liquid state at room temperature, thus achieving sterilization or disinfection requirements. It is commonly used for sterilization in enclosed spaces in the pharmaceutical, medical, and food industries. Vaporized hydrogen peroxide has been proven to be an effective surface sterilizing agent or disinfectant.

[0003] Vaporized hydrogen peroxide is generally produced by vaporizing a liquid mixture of hydrogen peroxide and water. Due to the differences in properties between water and hydrogen peroxide, existing vaporized hydrogen peroxide sterilization systems commonly suffer from the following problems:

[0004] 1. The problem of hydrogen peroxide decomposition caused by excessively high heating temperature during hydrogen peroxide vaporization. Because hydrogen peroxide and water have different boiling points, flash evaporation (rapid evaporation) technology is required during vaporization to avoid the separation of water and hydrogen peroxide during the evaporation process. Currently common flash evaporation technologies generally involve injecting the hydrogen peroxide solution onto the surface of an evaporator at a temperature higher than its boiling point, causing the hydrogen peroxide solution to evaporate rapidly. The boiling point of hydrogen peroxide solution increases with its concentration; for example, the boiling point of a commonly used 35wt% hydrogen peroxide solution is approximately 105℃~110℃. Therefore, to achieve flash evaporation of the hydrogen peroxide solution, the evaporator in existing hydrogen peroxide vaporization devices needs to be heated to at least 105℃. For example, patent CN102847178B discloses that the carrier gas needs to be heated to at least approximately 105℃; patent CN215690168U discloses that the heating temperature control is set at 150℃. Studies have shown that for every 10°C increase in temperature, the rate at which liquid hydrogen peroxide decomposes into water and oxygen doubles. While increasing the heating temperature can indeed increase the vaporization rate within a certain range (below the Leidenforst point), the decomposition rate of hydrogen peroxide will significantly increase with rising temperature, thus drastically reducing its utilization rate.

[0005] 2. Condensation and decomposition of hydrogen peroxide gas during transportation. Because hydrogen peroxide vapor pressure is much lower than water vapor, it easily condenses on the surfaces of objects through which the fluid passes during transportation and diffusion, reaching high concentrations in localized areas. While this surface condensation is beneficial for sterilization in those areas, under the set total injection volume, it can lead to a decrease in hydrogen peroxide concentration in other locations within the enclosed space, thus posing a risk of localized sterilization failure. Excessive injection, on the other hand, can result in excessive residual hydrogen peroxide due to condensation and accumulation, causing adverse effects such as material corrosion. Furthermore, hydrogen peroxide vapor transportation pipelines are generally made of metal, and metals have a much stronger catalytic effect on the decomposition of hydrogen peroxide than non-metals. Therefore, hydrogen peroxide gas is easily decomposed during transportation, affecting its sterilization effect. Simultaneously, the decomposition of hydrogen peroxide also leads to a significant temperature rise, especially in small-volume enclosed spaces.

[0006] 3. The problem of inconsistent sterilization effect due to constant hydrogen peroxide delivery conditions. Existing hydrogen peroxide sterilization systems typically have fixed heating module temperature, carrier gas temperature, carrier gas dew point temperature, and carrier gas flow rate, usually set at the maximum injection volume. However, in practical applications, when sterilizing a closed space, excessive addition of vaporized hydrogen peroxide (hydrogen peroxide solution contains a large amount of water) will cause a sharp increase in the relative saturation of the closed space. When the relative saturation of the closed space reaches 100%, because the dew point temperature of gaseous hydrogen peroxide is higher than that of water vapor, the hydrogen peroxide gas will condense first. Once hydrogen peroxide condenses, the hydrogen peroxide gas content in the closed space will drop sharply, while the water vapor content in the air will increase, leading to a deterioration in sterilization / disinfection effect. Summary of the Invention

[0007] The first objective of this invention is to overcome the problem of excessively high heating temperatures in existing hydrogen peroxide vaporization generators, which leads to the easy decomposition of hydrogen peroxide. This invention provides a low-temperature hydrogen peroxide vaporization generator that uses a micro-mist nozzle to uniformly spray hydrogen peroxide solution onto the surface of a heating plate, forming a liquid film. By utilizing the low-temperature vaporization technology of the liquid film, the injected hydrogen peroxide solution can be rapidly vaporized below the boiling point temperature of the hydrogen peroxide solution, thus avoiding excessive decomposition of hydrogen peroxide.

[0008] The second objective of this invention is to overcome the problem of condensation and decomposition of hydrogen peroxide gas during transportation in existing vaporized hydrogen peroxide sterilization systems. This invention provides a vaporized hydrogen peroxide sterilization system in which a pipe wall temperature monitoring sensor is installed on the hydrogen peroxide gas transportation pipeline to facilitate temperature control and ensure that hydrogen peroxide does not condense in the pipeline. Furthermore, a PTFE coating is applied to the inner wall of the transportation pipeline to reduce hydrogen peroxide decomposition.

[0009] The third objective of this invention is to overcome the problem of poor sterilization stability caused by constant hydrogen peroxide delivery conditions in existing vaporized hydrogen peroxide sterilization systems. This invention provides a low-temperature hydrogen peroxide vaporization generator and a vaporized hydrogen peroxide sterilization system, which adjusts the temperature, humidity, and flow rate of the carrier gas based on the amount of hydrogen peroxide solution injected and the test results of the hydrogen peroxide sensor in the space to be sterilized, thereby achieving stability and reproducibility of the sterilization effect.

[0010] To achieve the aforementioned first objective, the present invention adopts the following technical solution:

[0011] A hydrogen peroxide vaporization generator includes a carrier gas inlet unit and a hydrogen peroxide vaporization unit; the hydrogen peroxide vaporization unit includes a housing, a micro-mist nozzle disposed on the top of the housing, and a heating plate disposed inside the housing; the heating plate divides the interior of the housing into an upper vaporization chamber and a lower heating chamber; the side wall of the vaporization chamber is provided with an inlet and an outlet, the inlet being connected to the carrier gas inlet unit; the heating chamber is provided with a heating component;

[0012] The micro-mist nozzle includes a nozzle body and an airflow channel sleeve fitted over the nozzle body; the nozzle body includes a base and a nozzle pipe disposed below the base; the top of the base is provided with a compressed air inlet and a liquid inlet, the liquid inlet being connected to the nozzle pipe through a liquid flow channel; the airflow channel sleeve is fitted over the outside of the nozzle pipe, the inner diameter of the airflow channel sleeve is larger than the outer diameter of the nozzle pipe, a gas flow cavity is formed between the airflow channel sleeve and the nozzle pipe, the compressed air inlet being connected to the gas flow cavity through a gas flow channel; the bottom of the airflow channel sleeve tapers inward to form an inverted cone shape, and a gas outlet is provided at the bottom end of the airflow channel sleeve.

[0013] When the hydrogen peroxide vaporizer of this invention is used, hydrogen peroxide solution is sprayed onto the surface of the heating plate through a micro-mist nozzle. The hydrogen peroxide solution is heated and vaporized by the heating plate to obtain hydrogen peroxide gas. The hydrogen peroxide gas is carried out from the outlet by the carrier gas entering from the inlet for subsequent sterilization.

[0014] The micro-mist nozzle of this invention separates the liquid and gas flow channels by installing an airflow channel jacket over the nozzle body. During use, hydrogen peroxide solution is added through the liquid inlet and sprayed out along the nozzle through the liquid flow channel; while compressed air is added through the compressed air inlet and enters the gas flow chamber outside the nozzle along the gas flow channel. Because the bottom of the airflow channel jacket contracts inward, forming a smaller gas outlet, therefore, as... Figure 4As shown, under the influence of the Venturi effect, compressed air and hydrogen peroxide solution are ejected at high speed after passing through the orifice. The high-speed airflow around the perimeter cuts the hydrogen peroxide solution into atomized hydrogen peroxide that is evenly sprayed in all directions. The atomized hydrogen peroxide is sprayed onto the surface of the heating plate below, forming a 5-20 μm liquid film layer. This liquid film layer has a large vaporization surface area, resulting in rapid and uniform heat transfer. Therefore, this invention controls the temperature of the heating plate below 85°C, enabling rapid vaporization of the injected hydrogen peroxide solution. The vaporization temperature is far below the boiling point of the hydrogen peroxide solution.

[0015] Temperature is the main factor affecting the decomposition rate of hydrogen peroxide, and the change of the decomposition reaction rate constant K with temperature follows the Arrhenius equation:

[0016] k=Ae -Ea / RT (Formula 1)

[0017] In the formula: k is the rate constant, R is the molar gas constant, T is the thermodynamic temperature, Ea is the apparent activation energy, and A is the pre-exponential factor (also known as the frequency factor).

[0018] The relationship between decomposition rate and temperature can be expressed by the following formula:

[0019] (T2-T1)lgA=10 lg(k2 / k1) (Formula 2)

[0020] In the formula: k2 and k1 are the decomposition reaction rate constants at temperatures T2 and T1; T2 and T1 are the decomposition temperatures; A is the temperature coefficient, which is equal to 2.2.

[0021] According to the formula, when comparing evaporation at 105℃ (the boiling point of 35wt% hydrogen peroxide solution) with volatilization at 85℃, the former decomposes hydrogen peroxide more than 4 times faster (Note: the change from liquid to gas is called vaporization; vaporization at the boiling point is called evaporation; vaporization below the boiling point is called volatilization).

[0022] Therefore, the hydrogen peroxide vaporization generator of the present invention employs liquid thin film low-temperature vaporization technology, which can significantly reduce the vaporization temperature of the hydrogen peroxide solution, thereby reducing the decomposition of hydrogen peroxide during the vaporization process and greatly improving the utilization rate of hydrogen peroxide.

[0023] Preferably, the nozzle has an inverted conical nozzle at its bottom end, with a liquid injection port on the nozzle; the inner diameter of the gas outlet of the airflow channel jacket increases progressively from top to bottom. The inverted conical nozzle at the bottom end of the nozzle in this invention helps to further enhance the Venturi effect and improve atomization. The progressively increasing inner diameter of the gas outlet facilitates the uniform diffusion of atomized hydrogen peroxide in all directions, forming a uniform thin film on the heating plate surface.

[0024] Preferably, the base has a connecting part at its bottom for connecting with the airflow duct sleeve; the connecting part has a stepped double-layer boss structure, with its bottom connected to the nozzle; the airflow duct sleeve has a connecting sleeve at its top, fitted over the connecting part and matching its shape, with the upper boss of the connecting part fitting against the inner surface of the connecting sleeve, and the lower boss threadedly connected to the connecting sleeve. This invention connects the nozzle body to the airflow duct sleeve via the connecting part and the connecting sleeve, improving the strength and tightness of the connection and facilitating adjustment.

[0025] Preferably, the connecting sleeve has a built-in groove at the point where it fits against the upper boss, and a sealing ring is installed within the built-in groove. This invention provides a sealing ring at the connection between the nozzle body and the airflow channel sleeve, which improves the sealing performance of the gas flow chamber and prevents air leakage.

[0026] Preferably, the vaporization chamber is equipped with a carrier gas temperature sensor; the heating chamber is equipped with a heating component temperature sensor and a temperature control switch connected to the heating component; the temperature of the heating component is controlled between 65 and 85°C. The temperature control switch in the heating chamber prevents the heating component from burning out due to excessive temperature.

[0027] Preferably, the heating plate has a concave arc surface; the heating plate surface and the inner wall of the vaporization chamber are coated with a PTFE coating. The arc surface of the heating plate can match the shape of the atomized hydrogen peroxide sprayed from the micro-mist nozzle, making the formed liquid film uniform. Coating the heating plate surface and the inner wall of the vaporization chamber with a PTFE coating can avoid the catalytic decomposition of hydrogen peroxide by metal, thus reducing the decomposition of hydrogen peroxide.

[0028] Preferably, the carrier gas intake unit includes a parallel ambient air intake branch and a compressed air intake branch, as well as an intake main branch after the two branches merge; the ambient air intake branch is equipped with a carrier gas fan, and the compressed air intake branch is equipped with a compressed air interface, a dew point sensor, and a gas mass flow controller; the intake main branch is equipped with a carrier gas electronic flow meter, a dew point sensor, and a carrier gas heating core installed at the intake port of the hydrogen peroxide vaporization unit.

[0029] This invention incorporates parallel ambient air intake branches and compressed air intake branches in the carrier gas intake unit. It achieves adjustable carrier gas humidity by mixing ambient air (relative humidity 50%RH~65%RH) and dry compressed air (relative humidity ≤3%RH). The ratio of ambient air to compressed air can be adjusted via a gas mass flow controller on the compressed air intake branch; the carrier gas flow rate entering the hydrogen peroxide vaporization unit can be adjusted via a carrier electronic flow meter on the main intake branch; and the carrier gas temperature can be adjusted via a carrier gas heating core. This dynamic adjustment of carrier gas temperature, humidity, and flow rate ensures the stability and reproducibility of subsequent sterilization effects.

[0030] Preferably, the carrier gas heating core is provided with a mica heat insulation sleeve, and the carrier gas heating core is provided with a temperature control switch. The mica heat insulation sleeve can prevent the operator from being burned by external overheating; the temperature control switch can prevent the heating core from being burned by excessive temperature.

[0031] To achieve the second and third objectives of the invention, the present invention provides a vaporized hydrogen peroxide sterilization system, comprising the aforementioned hydrogen peroxide vaporization generator and a sterilization space connected to the outlet of the hydrogen peroxide vaporization generator via a delivery pipeline; the delivery pipeline is equipped with a pipe wall temperature monitoring sensor, and the inner wall of the delivery pipeline is coated with a PTFE coating; the sterilization space is equipped with a hydrogen peroxide sensor for measuring hydrogen peroxide concentration, saturation, and temperature; the hydrogen peroxide vaporization generator and the hydrogen peroxide sensor are connected to a PLC.

[0032] This invention incorporates a pipe wall temperature monitoring sensor in the hydrogen peroxide delivery pipeline. Before sterilization begins, the pipeline can be preheated with a carrier gas. The preheating temperature can be set based on the required hydrogen peroxide gas concentration, pipeline length, and hydrogen peroxide solution injection volume. During sterilization, the carrier gas temperature can be adjusted according to the pipe wall temperature to ensure that hydrogen peroxide does not condense in the pipeline before reaching the sterilization space. Simultaneously, this invention coats the inner wall of the delivery pipeline with a PTFE coating, reducing the catalytic decomposition of hydrogen peroxide by the metal pipe wall, thereby minimizing the decomposition of high-concentration hydrogen peroxide gas during delivery.

[0033] Furthermore, this invention incorporates a hydrogen peroxide sensor within the sterilization space. The PLC adjusts the relative humidity ratio of the carrier gas based on feedback from the hydrogen peroxide concentration, saturation, and temperature within the sterilization space. It also adjusts the temperature and flow rate of the carrier gas based on the amount of hydrogen peroxide solution injected into the hydrogen peroxide vaporization generator. By dynamically adjusting the temperature, relative humidity, and flow rate of the hydrogen peroxide gas delivery carrier, the stability and reproducibility of the sterilization effect are ensured.

[0034] Preferably, the system also includes an ambient temperature and humidity monitoring sensor connected to the hydrogen peroxide vaporization generator. Ambient temperature affects the wall temperature of the sterilization space, while ambient humidity affects the calculation of the carrier gas mixing ratio. Therefore, this invention includes an ambient temperature and humidity monitoring sensor in the system. Before sterilization, the ambient temperature and humidity are detected, and sterilization parameters are planned based on the ambient temperature and humidity data.

[0035] Therefore, the present invention has the following beneficial effects:

[0036] (1) A liquid film layer is formed on the surface of the heating plate by a micro-mist nozzle. The liquid film low-temperature vaporization technology can rapidly vaporize the injected hydrogen peroxide solution below the boiling point temperature of the hydrogen peroxide solution, reducing the decomposition of hydrogen peroxide during the vaporization process.

[0037] (2) A pipe wall temperature monitoring sensor was installed on the hydrogen peroxide gas delivery pipeline to facilitate control of the pipe wall temperature and ensure that hydrogen peroxide does not condense in the pipeline; and a PTFE coating was applied to the inner wall of the delivery pipeline to reduce the decomposition of hydrogen peroxide gas during the delivery process.

[0038] (3) By setting up each branch and main road in the carrier gas inlet unit, the temperature, relative humidity and flow rate of the hydrogen peroxide gas carrier gas can be dynamically adjusted to achieve the stability and reproducibility of sterilization data. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the connection structure of the hydrogen peroxide vaporization generator of the present invention.

[0040] Figure 2 This is a cross-sectional view of the micro-mist nozzle in Embodiment 1 of the present invention.

[0041] Figure 3 This is a cross-sectional view of the micro-mist nozzle in Embodiment 2 of the present invention.

[0042] Figure 4 This is a schematic diagram of the airflow distribution in the micro-mist nozzle of the present invention.

[0043] Figure 5 This is a schematic diagram of the connection structure of the vaporized hydrogen peroxide sterilization system of the present invention.

[0044] Figure 6 These are the hydrogen peroxide decomposition rate curves in the delivery pipelines of Example 1 and Comparative Example 1.

[0045] Figure 7 This is the sterilization data curve from Example 1.

[0046] Figure 8 This is the sterilization data curve from Comparative Example 2.

[0047] Figure 9 This is the sterilization data curve from Comparative Example 3.

[0048] In the diagram, components 1-5 are: 1. Housing; 2. Micro-mist nozzle; 201. Base; 202. Nozzle; 203. Airflow channel outer sleeve; 204. Compressed air inlet; 205. Liquid inlet; 206. Liquid flow channel; 207. Gas flow channel; 208. Gas flow chamber; 209. Gas outlet; 210. Nozzle; 211. Connecting part; 212. Connecting sleeve; 213. Sealing ring; 214. Positioning screw; 215. Adjusting gear; 216. Gear rear retaining ring; 217. Gear front retaining ring; 218. Drive gear; 219. Reducer; 220. Micro servo motor; 221. Fixed guide rail; 222. Slider; 3. Heating plate; 4. Vaporization chamber; 5. Heating chamber; 6. Air inlet; 7. Air outlet; 8. Heating component; 9. Heating component temperature sensor; 10. Temperature control switch; 11. Carrier gas temperature sensor; 12. Carrier gas fan. 13 Compressed air interface, 14 Dew point sensor, 15 Gas mass flow controller, 16 Carrier gas electronic flow meter, 17 Carrier gas heating element, 18 Manifold tee, 19 Hydrogen peroxide vaporizer, 20 Sterilization space, 21 Delivery pipeline, 22 Pipe wall temperature monitoring sensor, 23 Hydrogen peroxide sensor, 24 PLC, 25 Ambient temperature and humidity monitoring sensor. Detailed Implementation

[0049] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0050] Example 1:

[0051] like Figure 5 As shown, a vaporized hydrogen peroxide sterilization system includes a hydrogen peroxide vaporization generator 19, a sterilization space 20 connected to the hydrogen peroxide vaporization generator via a delivery pipeline 21, and an environmental temperature and humidity monitoring sensor 25 connected to the hydrogen peroxide vaporization generator.

[0052] The delivery pipeline is made of 316L stainless steel with a PTFE coating on the inner wall. A pipe wall temperature monitoring sensor 22 is installed on the delivery pipeline. A hydrogen peroxide sensor 23 is installed in the sterilization space to measure the hydrogen peroxide concentration, saturation and temperature; the hydrogen peroxide vaporization generator and the hydrogen peroxide sensor are connected to the PLC 24.

[0053] like Figure 1As shown, the hydrogen peroxide vaporization generator includes a carrier gas inlet unit and a hydrogen peroxide vaporization unit. The hydrogen peroxide vaporization unit includes a housing 1, a micro-mist nozzle 2 located on the top of the housing, and a heating plate 3 located inside the housing. The heating plate has a concave arc surface, dividing the interior of the housing into an upper vaporization chamber 4 and a lower heating chamber 5. The surface of the heating plate and the inner wall of the vaporization chamber are coated with a PTFE coating. The side wall of the vaporization chamber is provided with an inlet 6 and an outlet 7. The inlet is connected to the carrier gas inlet unit, and the outlet is connected to the sterilization space through a delivery pipeline. A carrier gas temperature sensor 11 is provided inside the vaporization chamber. The heating chamber is provided with a heating element 8, a heating element temperature sensor 9, and a temperature control switch 10 connected to the heating element. The heating element consists of multiple heating rods, and the temperature of the heating element is controlled at 85°C.

[0054] The carrier gas intake unit includes a parallel ambient air intake branch and a compressed air intake branch, as well as an intake main branch formed by the confluence of the two branches via a tee 18. The ambient air intake branch is equipped with a carrier gas fan 12, and the compressed air intake branch is equipped with a compressed air interface 13, a dew point sensor 14, and a gas mass flow controller 15. The intake main branch is equipped with a carrier gas electronic flow meter 16, a dew point sensor 14, and a carrier gas heating core 17 located at the inlet of the hydrogen peroxide vaporization unit. The carrier gas heating core is surrounded by a mica heat insulation sleeve, and a temperature control switch 10 is mounted on the carrier gas heating core.

[0055] like Figure 2As shown, the micro-mist nozzle in the hydrogen peroxide vaporization unit includes a nozzle body and an airflow channel sleeve 203 fitted over the nozzle body. The nozzle body includes a base 201 and a nozzle 202 located below the base. The base is located outside the housing 1, and the nozzle extends into the housing. The top of the base is provided with a compressed air inlet 204 and a liquid inlet 205, and the liquid inlet is connected to the nozzle through a liquid flow channel 206. The airflow channel sleeve is fitted over the outside of the nozzle, and the inner diameter of the airflow channel sleeve is larger than the outer diameter of the nozzle. A gas flow cavity 208 is formed between the airflow channel sleeve and the nozzle, and the compressed air inlet is connected to the gas flow cavity through a gas flow channel 207. The bottom end of the nozzle is provided with an inverted conical nozzle 210, and the nozzle is provided with a liquid injection port. The bottom of the airflow channel sleeve tapers inward to form an inverted conical shape, and the bottom end of the airflow channel sleeve is provided with a gas outlet 209, the inner diameter of which increases continuously from top to bottom; the gas outlet is directly opposite the center of the heating plate 3. The base has a connecting part 211 at its bottom for connecting with the airflow duct sleeve; the connecting part has a stepped double-layer boss structure, and the bottom of the connecting part connects to the nozzle; the top of the airflow duct sleeve has a connecting sleeve 212 that fits over the connecting part and matches its shape; the upper boss in the connecting part fits against the inner surface of the connecting sleeve, and the fitting area has an internal groove with a sealing ring 213 inside; the lower boss in the connecting part is threadedly connected to the connecting sleeve. The connecting sleeve has a positioning hole arranged radially, and a positioning screw 214 with a threaded connection is installed in the positioning hole.

[0056] In the vaporized hydrogen peroxide sterilization system of this invention, the ambient temperature and humidity are first detected by an ambient temperature and humidity monitoring sensor. Based on the ambient temperature and humidity data, the ratio of ambient air to compressed air in the carrier gas inlet unit of the hydrogen peroxide vaporization generator is set to adjust the carrier gas humidity. Then, the carrier gas is introduced to preheat the delivery pipeline. The preheating temperature is automatically set by the PLC based on the required hydrogen peroxide gas concentration for sterilization, the length of the delivery pipeline, and the amount of hydrogen peroxide solution injected into the hydrogen peroxide vaporization generator. After preheating, hydrogen peroxide solution and compressed air are introduced into the micro-mist nozzle through the liquid inlet and compressed air inlet, respectively. Figure 4 As shown, atomized hydrogen peroxide can be sprayed onto the surface of the heating plate below through a micro-mist nozzle to form a liquid film. The hydrogen peroxide gas generated after the liquid film vaporizes is sent into the sterilization space by the carrier gas through the delivery pipeline for sterilization. During the sterilization process, the PLC adjusts the relative humidity ratio of the carrier gas based on the feedback of hydrogen peroxide concentration, saturation and temperature in the sterilization space from the hydrogen peroxide sensor. Based on the amount of hydrogen peroxide solution injected into the hydrogen peroxide vaporization generator, the temperature and flow rate of the carrier gas are adjusted. Thus, by dynamically adjusting the temperature, relative humidity and flow rate of the hydrogen peroxide gas delivery carrier, the stability and reproducibility of the sterilization effect are ensured.

[0057] The sterilization data curves and the decomposition rate curve of hydrogen peroxide in the delivery pipeline of Example 1 are as follows: Figure 7 and Figure 6 As shown in the image.

[0058] Example 2:

[0059] The hydrogen peroxide vaporization generator in Example 2 uses an automatically adjustable micro-mist nozzle; the rest of the structure is the same as in Example 1. Figure 3 As shown, the difference between the micro-mist nozzle in Embodiment 2 and Embodiment 1 is that an automatic adjustment structure replaces the positioning screw 214 in Embodiment 1. The automatic adjustment structure includes an adjusting gear 215 fitted over a connecting sleeve on the top of the airflow channel outer sleeve, a drive gear 218 connected to the adjusting gear, a drive device connected to the drive gear, a fixed guide rail 221 arranged vertically, and a slider 222 whose one end is connected to the drive device and whose other end is located in the fixed guide rail and can move along the fixed guide rail. The drive device includes a reducer 219 connected to the drive gear and a miniature servo motor 220 connected to the reducer. A gear rear retaining ring 216 and a gear front retaining ring 217 are respectively provided on the upper and lower sides of the adjusting gear.

[0060] When using the micro-mist nozzle of Example 2, one side of the base is fixed. During adjustment, the drive device can move vertically along the fixed guide rail via a slider. The drive device drives the drive gear to rotate, the drive gear drives the adjustment gear to rotate, and the adjustment gear drives the airflow channel sleeve to rotate. Thus, through the threaded connection with the nozzle body, the relative position of the airflow channel sleeve and the nozzle body is adjusted, thereby realizing the automatic adjustment of the micro-mist nozzle.

[0061] Comparative Example 1:

[0062] In the vaporized hydrogen peroxide sterilization system of Comparative Example 1, the inner wall of the delivery pipeline was not coated with a PTFE coating; all other aspects were the same as in Example 1. The decomposition rate curve of hydrogen peroxide in the delivery pipeline of Comparative Example 1 is shown below. Figure 6 As shown in the image.

[0063] from Figure 6 As can be seen, in Comparative Example 1, where no PTFE coating is applied inside the stainless steel pipe, the decomposition rate of hydrogen peroxide is significantly higher compared to Example 1 where a PTFE coating is applied.

[0064] Comparative Example 2:

[0065] In the vaporized hydrogen peroxide sterilization system of Comparative Example 2, the hydrogen peroxide sensor 23 was not installed in the space to be sterilized. During sterilization, the carrier gas temperature, carrier gas flow rate, and carrier humidity remained constant, while all other parameters were the same as in Example 1. The sterilization curve of Comparative Example 2 is shown below. Figure 8 As shown in the image.

[0066] Comparative Example 3:

[0067] In Comparative Example 3, no pipe wall temperature monitoring sensor 22 was installed on the delivery pipeline; no carrier gas was used to preheat the delivery pipeline before sterilization; and the carrier gas temperature was not adjusted based on the pipe wall temperature during sterilization; everything else was the same as in Example 1. The sterilization curve of Comparative Example 3 is shown below. Figure 9 As shown in the image.

[0068] from Figures 7-9 As can be seen, in Example 1, the system and method of this invention are used for sterilization. During the sterilization process, the temperature, relative humidity, and flow rate of the hydrogen peroxide gas delivery carrier are dynamically adjusted based on the feedback from the hydrogen peroxide sensor regarding the concentration, saturation, and temperature of hydrogen peroxide in the space to be sterilized. This allows the concentration and relative saturation of hydrogen peroxide in the space to be sterilized to remain at a relatively stable level. In contrast, in Comparative Example 2, the carrier gas temperature, flow rate, and humidity are not dynamically adjusted based on the conditions within the space to be sterilized. As a result, the concentration and relative saturation of hydrogen peroxide in the space fluctuate significantly, leading to poor stability of the sterilization data. In Comparative Example 3, no pipe wall temperature monitoring sensor is installed on the delivery pipeline, and the temperature of the delivery pipeline is not adjusted based on the pipe wall temperature monitoring sensor. Because hydrogen peroxide condenses in the delivery pipeline, the stability of the sterilization data is similarly reduced compared to Example 1.

Claims

1. A hydrogen peroxide vaporization generator, characterized in that, Includes a carrier gas intake unit and a hydrogen peroxide vaporization unit; The hydrogen peroxide vaporization unit includes a housing (1), a micro-mist nozzle (2) disposed on the top of the housing, and a heating plate (3) disposed inside the housing; the heating plate divides the interior of the housing into an upper vaporization chamber (4) and a lower heating chamber (5); the side wall of the vaporization chamber is provided with an air inlet (6) and an air outlet (7), the air inlet being connected to a carrier gas inlet unit; the heating chamber is provided with a heating component (8), the temperature of which is controlled at 65~85℃; the surface of the heating plate is a concave arc surface; The micro-mist nozzle includes a nozzle body and an airflow channel sleeve (203) fitted over the nozzle body; the nozzle body includes a base (201) and a nozzle pipe (202) disposed below the base; the top of the base is provided with a compressed air inlet (204) and a liquid inlet (205), and the liquid inlet is connected to the nozzle pipe through a liquid flow channel (206); the airflow channel sleeve is fitted over the outside of the nozzle, the inner diameter of the airflow channel sleeve is larger than the outer diameter of the nozzle, and a gas flow cavity (208) is formed between the airflow channel sleeve and the nozzle pipe, and the compressed air inlet is connected to the gas flow cavity through a gas flow channel (207); the bottom of the airflow channel sleeve contracts inward to form an inverted cone shape, and a gas outlet (209) is provided at the bottom end of the airflow channel sleeve. The nozzle is provided with an inverted conical nozzle (210) at the bottom end, and the nozzle is provided with a liquid injection port; the inner diameter of the gas outlet of the airflow channel jacket increases continuously from top to bottom; The carrier gas intake unit includes a parallel ambient air intake branch and a compressed air intake branch, as well as an intake trunk after the two branches merge; the ambient air intake branch is equipped with a carrier gas fan (12), the compressed air intake branch is equipped with a compressed air interface (13), a dew point sensor (14) and a gas mass flow controller (15); the intake trunk is equipped with a carrier gas electronic flow meter (16), a dew point sensor (14) and a carrier gas heating core (17) installed at the intake port of the hydrogen peroxide vaporization unit.

2. The hydrogen peroxide vaporization generator according to claim 1, characterized in that, The base has a connecting part (211) at the bottom for connecting with the airflow duct sleeve; the connecting part has a stepped double-layer boss structure, and the bottom of the connecting part is connected to the nozzle; the top of the airflow duct sleeve has a connecting sleeve (212) that is fitted outside the connecting part and matches the shape of the connecting part, the upper boss in the connecting part fits with the inner surface of the connecting sleeve, and the lower boss is threadedly connected to the connecting sleeve.

3. The hydrogen peroxide vaporization generator according to claim 2, characterized in that, The connecting sleeve has an internal groove at the point where it fits against the upper boss, and a sealing ring (213) is provided inside the internal groove.

4. The hydrogen peroxide vaporization generator according to claim 1, characterized in that, The vaporization chamber is equipped with a carrier gas temperature sensor (11); the heating chamber is equipped with a heating component temperature sensor (9) and a temperature control switch (10) connected to the heating component.

5. The hydrogen peroxide vaporization generator according to claim 1, characterized in that, The heating plate surface and the inner wall of the vaporization chamber are coated with PTFE.

6. The hydrogen peroxide vaporization generator according to claim 1, characterized in that, The carrier gas heating core is provided with a mica heat insulation sleeve, and the carrier gas heating core is provided with a temperature control switch (10).

7. A vaporized hydrogen peroxide sterilization system, characterized in that, It includes a hydrogen peroxide vaporization generator (19) as described in any one of claims 1 to 6 and a sterilization space (20) connected to the outlet of the hydrogen peroxide vaporization generator via a delivery pipeline (21); the delivery pipeline is equipped with a pipe wall temperature monitoring sensor (22), and the inner wall of the delivery pipeline is coated with a PTFE coating; the sterilization space is equipped with a hydrogen peroxide sensor (23) for measuring hydrogen peroxide concentration, saturation and temperature; the hydrogen peroxide vaporization generator and the hydrogen peroxide sensor are connected to a PLC (24).

8. The vaporized hydrogen peroxide sterilization system according to claim 7, characterized in that, The system is also equipped with an ambient temperature and humidity monitoring sensor (25) connected to the hydrogen peroxide vaporization generator.

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