Air consists of nitrogen (78%), oxygen (21%) and the inert gas argon (0.9%). The remaining 0.1 % is made of mainly carbon dioxide and the inert gases like krypton, xenon, helium and neon. Now of the gas present in the atmosphere are used in industries. For example, nitrogen is extensively used in the industries and is known as the largest industrially consumed industrial gas. And, oxygen is called the 2nd largest industrially consumed gas. However, the question remains how oxygen and nitrogen are separated from the atmospheric for use in industrial applications.
Separation of Gases from Air
Fractional distillation is used for separating the gases such as oxygen and nitrogen. Carbon dioxide is cooled to -79 C and is removed. Oxygen is liquefied at -183 C and nitrogen is liquefied at -196 C. The mixture of oxygen and nitrogen is moved to the bottom of a fractionating column. As liquid nitrogen boils first, rises to the top of the column and is dispatched off for storage. On the other hand, oxygen settles at the bottom of the column. It is also moved into cryogenic storage.
For industrial applications, oxygen plants, nitrogen plants and air separation plants are available in the market. Industries now like to have on-site air separation plants for meeting their requirements of oxygen and nitrogen. In the fabricating of the plant machinery, only the best quality raw materials are used. Cryogenic distillation technology is used in the making of the machinery that can help generate oxygen with purity up to 99.7% and nitrogen with purity up to 99.99%.Functioning of the plant machinery is based on the process cycle of Linde & Claude, which is developed in 1930s and has since been updated many times. Standard air separation plants are given ISO 9001:2008 and CE certifications.