The air we breathe consists mainly of two gases, nitrogen and oxygen. At very low temperatures both these gases liquefy. The everyday air that you breathe can be converted to liquid oxygen. The conversion repeats steps over and over that compress, cool, and reheat nitrogen and oxygen until it reaches a liquid form.
To convert nitrogen and oxygen gas to a liquid it must be repeatedly compressed under pressure and cooled then expanded with warming to lower the temperature further. Oxygen becomes liquid when cooled to -312 degrees Fahrenheit (-183 C) and nitrogen liquefies when cooled to -321 degrees Fahrenheit (-196 C). When the nitrogen is heated back to -312 degrees Fahrenheit (-183 C) it will evaporate leaving pure pale blue colored liquid oxygen.
Liquid oxygen should not be confused with liquid hydrogen that is created by using a method of compression. Liquid hydrogen has many medical uses but has a hopeful future as an alternative fuel source for internal combustion engines and fuel cell cars. Instead of greenhouse gases, using hydrogen for fuel emits just water vapor.
Flow oxygen is used medically for inhalation therapy generally for arterial oxygenation. High flow oxygen inhalation therapy has been successfully used for many things including cluster headaches, COPD, emergency treatment, chronic conditions, and more. Flow oxygen therapy is widely used in hospitals and, because of advancements in technology, in the homes everywhere.
Liquid oxygen can be stored easier and in much less space than oxygen gas. Personal use flow oxygen is available in light weight portable units. These portable units can be refilled from a home based unit making home oxygen therapy very convenient. This new age equipment creates a personal home oxygen plant eliminating the need for costly commercial oxygen deliveries.
Flow oxygen usage has expanded into an entirely new area. In 1990’s Japan, flow oxygen became popular for commercial use. The Oxygen Bar craze spread from Las Vegas to New York and many places in between. Oxygen Bars started selling non-medical oxygen for about one dollar a minute for recreational use. By creating oxygen using safer commercial oxygen generators instead of high-pressure cylinders a new industry was born.
There has been a radical change in oxygen therapy. Oxygen therapy patients were once house bound by large heavy stationary oxygen tanks and big machines. These old oxygen tanks were dangerous because oxygen was stored under pressure and could be very dangerous if dropped or used near an open flame. The commercial development of flow oxygen concentrators made home and portal units smaller and more affordable for home use. No longer is there a need to order an oxygen delivery or to run out of oxygen. Smaller safer home units have replaced the cost and danger of the oxygen tanks of yesterday. Today oxygen therapy patients have the freedom to go anywhere with a light weight refillable portable oxygen supply.