METHOD OF PURIFYING AND LOW TEMPERATURE SEPARATING AIR WITHOUT PRECOOLING AND PLANT THEREFOR

摘要

PROBLEM TO BE SOLVED: To unnecessitate precooling, to simplify a treating process, and to reduce manufacturing costs by introducing compressed air into an adsorption vessel without precooling to adsorb impurities to purify it before cooling the purified air to very low temperature before subjecting it to low temperature distillation. SOLUTION: After the air containing impurities of CO2 and/or steam type is compressed to pressure of about 11.4105 Pa by a compressor 1, and is a little adjusted by a water flow heat exchanger 7 from the view point of temperature, the compressed air is introduced into one of adsorbing devices 3a, 3b packed with adsorbent of zeolite type. At this time, the compressed air is introduced at temperature of +15 deg.C or more and at pressure of at least 11.4106 Pa, and the impurities are adsorbed by the adsorbent there to obtain purified gas. Next, it is cooled in a cold box 4 containing one or more heat exchangers to very low temperature, for example, -120 deg.C, and after that, for the purpose of manufacturing nitrogen and/or oxygen, they are separated by low temperature distillation in a low temperature distillation column 5.