Working Of Cryogenic Air Separation Unit

By Author: Universal Boschi
Total Articles: 4
Comment this article

We use an air separation unit for producing oxygen & nitrogen for industrial and medical applications. To take up the case of oxygen, it is absolutely necessary for sustaining life on the planet earth. There is no denying the fact that one cannot survive without oxygen beyond 5 minutes. It is valued for its reactivity and its readiness to form oxides with most of the other elements and compounds. O2 is considered the 3rd most plentiful element in the universe by mass after hydrogen and helium. The nonmetallic gas is said to constitute 21% of planet Earth’s atmosphere by mass and 23% by weight. It is said that oxygen comprises almost half of Earth’s crust by mass in the form of oxides.

Nitrogen with purity up 99.9 per cent is required for applications in industrial and medical applications. Since nitrogen present in the atmosphere is only 78% the rest being oxygen and other gases found only in traces, it requires the use of an air separation for industrial production of high purity nitrogen. In fact, nitrogen is the most industrially consumed gas with oxygen as the 2nd largest industrially consumed gas. Numerous ...
... industrially important compounds are comprised of nitrogen including cyanides, ammonia, nitric acid, and organic nitrates. It is also found in all living organisms in the form of amino acids, nucleic acids, etc. The nonmetallic element makes around 3% mass of the human body and is the most plentiful element in the body after oxygen, carbon and hydrogen. Nitrogen is an inert gas which is a property that finds extensive applications in the industry.

How Air Separation Unit Works

Working of cryogenic air separation unit (ASU) is based on cryogenic distillation process developed at the start of the century by Linde & Claude and has been updated with every new advancement in the cryogenic field. It is even now considered the most efficient technology for producing high purity oxygen and nitrogen on a large scale. There are other technologies also available such pressure swing adsorption (PSA) for generating oxygen and nitrogen but are suitable only for low purity oxygen and nitrogen production on a smaller scale.

Working of ASU begins with the intake of the atmosphere air and concludes with the storage of the gases in the cryogenic tank. The air is compressed and is forwarded to the purification system where impurities like hydrocarbons, carbon dioxide and moisture are removed. Afterwards, the air is passed through a series of heat exchangers where it is cooled to extremely low temperatures. After achieving liquefaction, the air goes into a high pressure distillation column where separation of air into constituent parts —nitrogen, oxygen and argon takes place. The chosen gases are distilled in the low pressure distillation column to get the desired purity. A typical ASU is comprises of cryogenic tank, vaporizer, pressure and temperature control monitoring system. Vaporizer is used for converting liquid oxygen or nitrogen into their gaseous form.

Universal Boschi is the author of this article. We are trusted oxygen plant manufacturer that performs seamlessly using high quality materials and the advanced technology.