Abstract

Oxygen is a key element for the existence of life on earth as well as an ingredient for a wide variety of manufacturing processes. Oxygen is produced commercially by the cryogenic separation of air into mainly oxygen and nitrogen or by vacuum swing adsorption procedures. The oxygen is transported to users primarily by pipelines as a high pressure gas or within tank trucks as a cryogenic liquid. Most oxygen is used captively. It is widely used in steel and other metal refining and fabrication industries as well as in the production of many petrochemicals and in health-related fields. Specifications depend on use.

In some cases oxygen is used as a replacement for air in a process; in other applications air is enriched in oxygen. In many applications, reducing or eliminating the nitrogen normally present in the air typically increases the combustion temperature, increases the yield of product formed, and reduces the volume of waste gas to be treated.