Argon gas and its usage in Steel Plant...

Argon gas and its usage in Steel Plant Argon (Ar) gas is present in very small percentage in the atmosphere. Argon is very inert and hence it is referred to as one of the noble gases. It is not known to form true chemical compounds. It makes a good atmosphere for working with air sensitive materials since it is heavier than air and less reactive than nitrogen gas. Argon gas is the most abundant of the noble gases. It is a non-reactive component of the atmosphere. It constitutes 0.934 % by volume and 1.288 % by mass of the earth’s atmosphere. Argon was suspected to be present in air by Henry Cavendish in 1785 but was not isolated until 1894 by Lord Rayleigh and Sir Willam Ramsay at University college London in an experiment in which they removed all of the oxygen, carbon dioxide, water and nitrogen from a sample of clean air. Argon gas is produced by the fractional distillation of liquid air at the cryogenic air separation plants. It is produced, most commonly, in conjunction with the manufacture of high purity oxygen using cryogenic distillation of air.  Since the boiling point of argon is very close to that of oxygen (a difference of only 2.9 deg C) separating pure argon from oxygen (while also achieving high recovery of both products) requires many stages of distillation. For many decades, the most common argon recovery and purification process used several steps namely (i) taking of a side-draw stream from the primary air separation distillation system at a point in the low-pressure column where the concentration of argon is highest, (ii) processing the feed in a crude argon column which  returns the nitrogen to the low pressure column and produces a crude argon product, (iii) warming the crude argon and reacting...