Application of compressed air purification in medicine

In modern medical environment, compressed air has become an indispensable "source power" for life support and equipment driving, just like oxygen and electricity. However, medical compressed air has extremely strict requirements on purity, dryness, safety and reliability, which is far from comparable to ordinary industrial compressed air.

Why must medical compressed air be deeply purified?

Under-purified compressed air may contain:

1. Moisture: Causes pipeline corrosion, breeds bacteria and microorganisms, damages precision instruments, and may freeze and block pipelines in cold environments.

2. Oil: Mainly comes from air compressor lubricating oil. Even oil-free machines need to prevent environmental oil and gas pollution. Oil pollution can damage equipment and contaminate drugs

3. Solid particles: Contaminate sterile areas, block equipment precision air circuits, and damage valves.

4. Microorganisms and bacteria: A humid environment with nutrient sources (oil) is a hotbed for microbial growth and is very likely to cause hospital infections.

Medical purification systems usually use multi-stage deep treatment:

1. Pre-filtration:

Function: Remove large solid impurities (such as dust >1μm, pipe peelings) and most liquid water and oil.

Equipment: Precision coalescing filter

2. Drying treatment:

Refrigerated dryer: Cools compressed air to a dew point of 2-10°C, precipitating a large amount of liquid water. Economical and commonly used, but the dew point is not low enough.

Adsorption dryer: Uses desiccant to deeply adsorb water vapor, which can reduce the pressure dew point to -20°C to -70°C or even lower, completely eliminating the risk of liquid water and inhibiting the growth of microorganisms. Double or multi-tower design is required to ensure continuous air supply.

3. Post-deep filtration:

Function: Further remove micron-level and submicron-level solid particles, fine oil mist and residual water vapor.

Equipment:

Particle filter: High-precision filter element to remove fine particles and microbial carriers.

Activated carbon filter: uses the huge surface area of ​​activated carbon to absorb oil vapor, odor and some harmful gases.

Sterilization grade filter: located upstream of the point of use or directly integrated on the terminal equipment, using hydrophobic filter membrane, effectively blocking bacteria, viruses and other microorganisms, is the last line of defense against infection.