Liquid oxygen is easy to store and transport which is the chief reason hospitals go for liquid oxygen. However, let’s first understand why oxygen is used in the first place in hospitals. Oxygen is vital for maintaining life on the planet earth. Hospitals use oxygen for treating conditions like cardiac/respiratory arrest, cyanosis, COPD, severe hemorrhage, carbon monoxide poisoning, major trauma, shock, etc. It is also used in all modern anesthetic techniques. Moreover, it is also administered as a life support to patients.
Hospitals prefer using liquid because they are easier to store and its storage cost remains low. If gaseous oxygen is stored, it is costly and there are more chances of its leakage which adds to the cost. Importantly, oxygen is used as gas in all its medical applications. Liquid oxygen plants have vaporizers that convert liquid oxygen which is then fed into the hospital piping system so it could reach the patients. So, we can see that oxygen is primarily used as gas in medical as well as industrial applications while it is preferred to be stored and transported as a liquid.
Production of Oxygen in Hospitals:
Oxygen plant for hospitals produces high purity oxygen by liquefaction of the atmospheric air. The plant taps atmospheric air and compresses in the air compressor which is then pressured into a cleanup system where impurities such as carbon dioxide, hydrocarbons and moisture are removed. Then, the air is pressed into a heat exchanger where it is cooled to cryogenic temperatures. At this point, the air is moved into the high pressure distillation column where oxygen is separated nitrogen. In the distillation column, oxygen is formed at the bottom and is distilled till it meets its specifications.
Medical Oxygen Specifications:
Medical oxygen used in the hospitals has purity of 99.7% and meets the standards of European and Indian Pharmacopeia standards. It also meets the criteria of identification, odor, CO2 not more than 0.03% and CO not more than 0.001% in gas.