Non-isothermal regeneration of molecular sieve adsorbers in a cyclic process of air purification from moisture and carbon dioxide

Abstract

Non-isothermal desorption of moisture and carbon dioxide from a layer of molecular sieve NaX has been studied on the basis of the proposed mathematical model. It is shown that it is not expedient to maintain the carbon dioxide desorption temperature above 353 K in the real industrial process while the minimum temperature of the moisture desorption should be within the range 373–423 K. The application of the thermal wave adsorption method to the problem of regeneration from the main impurities of air allows the power consumption to be significantly reduced. A simplified model of a cyclic process of air purification under incomplete desorption of moisture has been suggested. A comparison is made of the results of the calculations and the test data obtained on the commercial adsorbers of a low-pressure air separation plant when the regenerating gas temperature is decreased from 653 to 373 K. Good qualitative and satisfactory quantitative agreement of the calculated and observed results is observed.