Sterilization cabinet sterilization and drying method

Abstract

The application discloses a sterilization drying method of a sterilization cabinet, which comprises a heating stage, the heating stage alternately inputs steam and performs vacuum pumping, wherein the input of the steam increases the pressure in the sterilization cabinet by ΔP1, the vacuum pumping decreases the pressure in the sterilization cabinet by ΔP2, ΔP1>ΔP2, until the pressure in the sterilization cabinet reaches a sterilization pressure and the temperature reaches a sterilization temperature after the n-th input of the steam, n≥3, the temperature in the sterilization cabinet in the heating stage is 100-134 DEG C, and the pressure is 0.1-2.1 bar. The heating stage alternately inputs steam and performs vacuum pumping for multiple times, and the pressure compensation value of the input of the steam is greater than the pressure relief value of the vacuum pumping, so that the sterilization pressure and the sterilization temperature are gradually approached in steps, the sterilization process is smoother, the sterilization temperature is effectively prevented from being too high and overshooting at the moment of reaching the set temperature, the balance time of the temperature rising to the sterilization process is reduced, the uniformity of the temperature is improved, and the subsequent sterilization process meets the requirements of relevant regulations on drug production.

Description

Technical Field

[0001] This invention relates to the field of high-pressure steam sterilizers, and more particularly to a sterilization and drying method for a sterilizer. Background Technology

[0002] Currently, high-pressure steam sterilizers generally use a pulsed vacuum method followed by heating for sterilization. Due to the significant temperature difference between the product to be sterilized and the sterilizing steam, a large amount of condensation is generated during heating, resulting in a substantial extension of the drying time after sterilization and a high risk of ineffective drying. Furthermore, the excessively long time required to reach the sterilization temperature leads to excessive condensation, resulting in large temperature differences and uneven temperature distribution. This also makes it highly susceptible to excessively high sterilization temperatures, leading to poor temperature uniformity and prolonged equilibration times, thus failing to meet current pharmaceutical production regulations. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a sterilization and drying method for a sterilizer that helps to smoothly enter the sterilization process, shortens the equilibrium time from heating to the sterilization process, and improves temperature uniformity.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] A sterilization and drying method for a sterilizer includes a heating stage, wherein steam and vacuum are alternately introduced during the heating stage. The steam introduction increases the pressure inside the sterilizer by ΔP1, and the vacuum decreases the pressure inside the sterilizer by ΔP2, where ΔP1 > ΔP2, until the pressure inside the sterilizer reaches the sterilization pressure and temperature reaches the sterilization temperature after the nth steam introduction, where n ≥ 3. During the heating stage, the temperature inside the sterilizer is 100–134°C, and the pressure is 0.1–2.1 bar.

[0006] As a further improvement to the above technical solution: 200mbar≤ΔP1≤600mbar, 150mbar≤ΔP2≤450mbar.

[0007] As a further improvement to the above technical solution: 300mbar≤ΔP1≤500mbar, 200mbar≤ΔP2≤300mbar.

[0008] As a further improvement to the above technical solution: the heating stage is preceded by a preheating stage, in which hot air is blown and a vacuum is drawn to maintain a set pressure P1 inside the sterilizer for a duration of T1.

[0009] As a further improvement to the above technical solution: the temperature of the input hot air is 100~140℃, 100m bar≤P1≤150m bar, and 15min≤T1≤25min.

[0010] As a further improvement to the above technical solution: the preheating stage is followed by a postheating stage. In the postheating stage, a vacuum is first drawn to reduce the pressure inside the sterilizer from P1 to P2, and then steam is introduced to increase the pressure from P2 to P3 within time T2, where P3 > P1.

[0011] As a further improvement to the above technical solution: 80mbar≤P2≤120mbar, 300mbar≤P3≤500mbar, 10min≤T2≤20min.

[0012] As a further improvement to the above technical solution: the preheating stage and the heating stage include a pulsating stage, in which steam is alternately input and vacuum is drawn, the number of alternations being m, where m≥3. After steam is input, the pressure inside the sterilizer rises to P4, where 600mbar≤P4≤1000mbar. After vacuum is drawn, the pressure inside the sterilizer drops to P5, where 80mbar≤P5≤120mbar.

[0013] As a further improvement to the above technical solution: the heating stage is followed by a sterilization stage, in which steam is input to maintain the temperature inside the sterilization cabinet within a set range.

[0014] As a further improvement to the above technical solution: after the sterilization stage, there is a drying stage, in which hot air is blown and vacuum is drawn at the same time. The flow rate of the input hot air is cyclically reduced k times, then maintained within a set range and finally increased, where k≥3.

[0015] Compared with the prior art, the advantages of the present invention are as follows: The sterilization and drying method of the sterilization cabinet disclosed in the present invention alternates between steam input and vacuuming multiple times during the heating stage, and the pressure replenishment value of the input steam is greater than the pressure relief value of the vacuuming. This stepwise approach to the sterilization pressure and sterilization temperature makes the sterilization process smoother. It effectively prevents the sterilization temperature from being too high or overshooting at the moment of reaching the set temperature, reduces the equilibrium time of heating to the sterilization process, and improves the temperature uniformity, so that the subsequent sterilization process complies with the relevant regulations for pharmaceutical production. Attached Figure Description

[0016] Figure 1 This is a graph showing the existing sterilization and drying methods in sterilizers.

[0017] Figure 2 This is a graph showing the sterilization and drying method of the sterilization cabinet of the present invention. Detailed Implementation

[0018] In the description of this invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0020] In this invention, unless otherwise explicitly specified and limited, the terms "assembly," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 2 An embodiment of the sterilization and drying method of the sterilizer of the present invention is shown. The specific sterilization and drying method of the sterilizer in this embodiment is as follows:

[0023] Preheating stage: Vacuuming is performed simultaneously with purging with hot air at 110–125°C. The vacuum level is controlled to 120 mbar and maintained for 20 minutes by adjusting the flow rate of the hot air. This preheating stage can increase the base temperature of the sterilized product, thereby reducing the generation of condensate during heating and sterilization.

[0024] In the later preheating stage: first, evacuate the vacuum as quickly as possible to reduce the pressure to 100 mbar, then adjust the flow rate of the input steam and gradually increase the pressure to 400 mbar within 15 minutes. During this later preheating stage, by slowly replenishing steam, the temperature difference between the items to be sterilized and the steam is gradually reduced, thereby minimizing the generation of large amounts of condensate due to excessive temperature differences and improving the drying efficiency after sterilization.

[0025] Pulsating Phase: First, replenish steam to 800 mbar as quickly as possible, then quickly evacuate to 100 mbar, replenish steam to 800 mbar again, and evacuate to 100 mbar again, repeating this cycle three times. The pulsating process is to remove air from the sterilizer, achieving a state of almost pure steam, thereby improving temperature uniformity within the sterilizer during heating and facilitating rapid heating.

[0026] Heating Phase: Steam is replenished from 100 mbar to 500 mbar, then vacuumed from 500 mbar to 300 mbar, steam is replenished from 300 mbar to 700 mbar, and then vacuumed from 700 mbar to 450 mbar. This steam replenishment and vacuuming process is repeated alternately at least three times. Each replenishment pressure is 400 mbar, and each depressurization pressure is 200–250 mbar, until steam is replenished to the sterilization pressure, and the sterilization temperature inside the sterilizer reaches the set sterilization temperature. The alternating vacuuming and steam replenishment during the heating phase continuously approaches the sterilization pressure and achieves sterilization stability, resulting in a smoother sterilization process, reduced equilibrium time from temperature rise to sterilization, and improved temperature uniformity, making the sterilization process more compliant with regulations. The initial heating temperature is 100–121°C, corresponding to a pressure of 0.1–1.1 bar, and the sterilization temperature is typically 134°C, corresponding to a pressure of 2.1 bar.

[0027] Sterilization stage: The temperature inside the sterilization chamber is maintained within the sterilization temperature range by continuously adjusting the flow rate of the input steam to meet the sterilization requirements.

[0028] Drying stage: A vacuum is applied simultaneously with hot air at 100-125℃ for purging. The vacuum is controlled to 120 mbar by adjusting the flow rate of the hot air, and maintained for 10 minutes. Then, the pressure is increased to 900 mbar by adjusting the flow rate of the hot air, and maintained for 15 minutes. This cycle is repeated three times. The drying stage utilizes the principle of low boiling point under vacuum to achieve rapid drying.

[0029] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the scope of the present invention, should fall within the protection scope of the present invention.

Claims

1. A sterilization and drying method in a sterilizer, characterized in that: The process includes a heating phase, in which steam and vacuum are alternately introduced. Steam introduction increases the pressure inside the sterilizer by ΔP1, while vacuuming decreases the pressure by ΔP2, where ΔP1 > ΔP2. This continues until the nth steam introduction, after which the pressure and temperature inside the sterilizer reach the sterilization pressure and temperature, respectively, where n ≥ 3. During the heating phase, the temperature inside the sterilizer is 100~134℃, and the pressure is 0.1~2.1 bar. Before the heating phase is a preheating phase, hot air purging and vacuuming are performed to maintain a set pressure P1 inside the sterilizer for a duration T1. After the preheating phase is a post-preheating phase, vacuuming is first performed to decrease the pressure inside the sterilizer from P1 to P2, and then steam is introduced to increase the pressure from P2 to P3 within time T2, where P3 > P1.

2. The sterilization and drying method for a sterilizer according to claim 1, characterized in that: 200mbar≤ΔP1≤600mbar, 150mbar≤ΔP2≤450mbar.

3. The sterilization and drying method for a sterilizer according to claim 2, characterized in that: 300mbar≤ΔP1≤500mbar, 200mbar≤ΔP2≤300mbar.

4. The sterilization and drying method for a sterilizer according to claim 1, characterized in that: The temperature of the input hot air is 100~140℃, 100m bar≤P1≤150 mbar, and 15min≤T1≤25min.

5. The sterilization and drying method for a sterilizer according to claim 1, characterized in that: 80mbar≤P2≤120mbar, 300mbar≤P3≤500mbar, 10min≤T2≤20min.

6. The sterilization and drying method for a sterilizer according to claim 5, characterized in that: The preheating stage and the heating stage are separated by a pulsating stage, in which steam is alternately input and vacuum is drawn, with the number of alternations being m, where m≥3. After steam is input, the pressure inside the sterilizer rises to P4, where 600mbar≤P4≤1000mbar. After vacuum is drawn, the pressure inside the sterilizer drops to P5, where 80mbar≤P5≤120mbar.

7. The sterilization and drying method for a sterilizer according to any one of claims 1 to 6, characterized in that: The heating stage is followed by a sterilization stage, in which steam is introduced to maintain the temperature inside the sterilization chamber within a set range.

8. The sterilization and drying method for a sterilizer according to claim 7, characterized in that: The sterilization stage is followed by a drying stage, in which hot air is blown and vacuum is drawn. The flow rate of the input hot air is cyclically reduced, maintained within a set range, and then increased k times, where k ≥ 3.

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