Sterilization principle
High-pressure steam sterilization uses latent heat released by high pressure and high heat for sterilization. The principle is that in a closed container, the boiling point of water increases due to the increase in steam pressure, thereby increasing the temperature of the steam for effective sterilization.
When using a high-pressure steam sterilizer, the cold air in the sterilizer must be completely discharged. Because the expansion pressure of air is greater than the expansion pressure of water vapor, when water vapor contains air, the pressure shown on the pressure gauge is not the actual pressure of the water vapor, but the sum of the water vapor pressure and the air pressure.
Because under the same pressure, the temperature of steam containing air is lower than the temperature of saturated steam, so when the sterilizer is heated to reach the required sterilization pressure, if it contains air, the required sterilization cannot be achieved in the sterilizer. temperature, the sterilization effect will not be achieved.
High pressure steam sterilizer classification
There are two types of high-pressure steam sterilizers: bottom-row pressure steam sterilizers and vacuum pressure steam sterilizers. Down-row pressure steam sterilizers include portable and horizontal types.
(1) The bottom row pressure steam fire sterilizer has double exhaust holes at the lower part. During sterilization, the density of hot and cold air is different. The hot steam pressure in the upper part of the container causes the cold air to be discharged from the exhaust holes at the bottom. When the pressure reaches 103 kPa ~ 137 kPa, the temperature can reach 121.3℃-126.2℃, and sterilization can be achieved in 15 min ~30 min. The temperature, pressure and time required for sterilization are adjusted according to the type of sterilizer, the nature of the items and the size of the packaging.
(2) Pre-vacuum pressure steam sterilizer is equipped with an air vacuum pump, which evacuates the interior before introducing steam to form a negative pressure, making it easy for steam to penetrate. At a pressure of 206 kP and a temperature of 132°C, it can be sterilized in 4 to 5 minutes.
Post time: Oct-10-2023
