1 air
A mixture of gases that exist on the surface of the earth. The density of air close to the ground is 1.29kg/m3 under standard condition. The main components are oxygen, nitrogen and argon; In terms of volume content, oxygen accounts for about 20.95%, nitrogen accounts for about 78.09%, argon accounts for about 0.932%. In addition, it also contains trace hydrogen, neon, helium, krypton, xenon and other rare gases. According to different regional conditions, it also contains carbon dioxide, water vapor, acetylene and other hydrocarbons.
2 processing air
It refers to the raw air used to separate gas and make liquid.
3 oxygen
Molecular formula O2, molecular weight 31.9988 (according to 1979 international atomic weight), colorless, odorless gas. The density under standard condition is 1.429kg/m3, the melting point is 54.75k, and the boiling point is 90.17k at 101.325kpa. The chemical property is very active and it is a strong oxidant. It can't burn, it can support combustion.
4 process oxygen for industrial use
The oxygen content of industrial process oxygen produced by air separation equipment is generally less than 98%（ Volume ratio)
5 gaseous oxygen for industrial use
The oxygen content of industrial gaseous oxygen produced by air separation equipment is more than or equal to 99.2%（ Volume ratio)
6 high purity oxygen
The oxygen content produced by air separation equipment is more than or equal to 99.995% (volume ratio).
7 liquid oxygen (liquid oxygen)
Oxygen in liquid state is sky blue, transparent and easy to flow liquid. At 101.325kpa, the boiling point is 90.17k and the density is 1140kg / m3. It can be produced by low temperature air separation equipment or by gaseous oxygen liquefaction.
