When the cleaning of the fermentation system is completed, the next step is to decontaminate the fermenter (disinfection of the empty tank).
The definition of air elimination: remove bad or unnecessary impurities in the space to make it reach a harmless cleanliness or within a certain space range, remove the pollutants such as fine particles, volatile harmful substances, bacteria and so on in the space.
Empty disinfection method: The most common method is to use steam to sterilize empty tanks. The conventional air disinfection method uses steam to sterilize the tank body. The operations include opening steam, exhausting air, maintaining pressure, draining water, and opening sterile air, etc., which are generally manual operations.
Advantages of steam air elimination
High steam temperature and strong penetrating power
The latent heat of steam is large, which can rapidly increase the temperature of objects. The penetrating power of steam molecules is strong, and it is easy to coagulate and denature proteins. Studies have shown that at high temperatures of 120°C-130°C, bacterial spores can be completely killed within 20 to 30 minutes. , The qualified rate of sterilization is 100%.
Steam sterilization without pollution and residue
Steam is the steam generated by the steam generator by heating water, without adding any chemical components, which guarantees the safety of sterilization from the source. In addition, no physical pollution will be produced during the sterilization process, and it can truly be pollution-free and residue-free. After the sterilization is completed, no waste gas and waste water will be produced, which saves the trouble of discharge.
Short steam sterilization time and high efficiency
In high-pressure steam sterilization, the sterilization temperature increases with the increase of steam pressure, which can greatly shorten the sterilization time and improve work efficiency. Saturated steam flows dynamically in the sterilizer, and the heat energy of the steam is evenly distributed on the medical equipment. Under the action of high temperature and high pressure, bacteria are quickly killed.
research shows. When the steam temperature is above 132°C and maintained for 10 minutes, all microorganisms including spores and spores with strong resistance can be killed.
Advantages of hot water air disinfection
Sterilize faster and more thoroughly
When the air in the tank is exhausted through the temperature gradient of each heat transfer layer, the use of hot water is faster and more thorough than that of steam. In the air elimination operation, exhaust is a very critical operation.
It can be seen from the above figure that with the presence of air less than 1mm, the steam conducts from 121°C to the place separated by air, and drops to only a little over 100°C. It is conceivable that at this temperature, if it is maintained for 30 minutes , the sterilization operation is not up to the requirements. In hot water air purifiers, due to the obvious difference in specific gravity, hot water exhaust is faster and more thorough than steam exhaust.
Sterilization process is more energy-efficient
The heat loss of hot water decontamination is only the radiant heat conducted to the outside world, while the process of steam decontamination, exhaust and drainage have taken away a lot of energy.
Highly reliable and consistent sterilization results with a high degree of automation
This is the same as the CIP automatic cleaning technology, using hot water for air disinfection is more conducive to the logical judgment of the automation system. The hot water is emptied, which reduces the labor intensity of personnel, ensures the exhaust effect, and ensures that there is no dead angle for sterilization. All of these ensure highly reliable and consistent sterilization.
At present, in the hygienic fields such as pharmaceuticals and food, the air disinfection system and the in-place cleaning system are basically integrated, and the combination of the SIP system and the CIP system can ensure the best cleaning and sterilization effects.