Generation flow rate leveling method and apparatus for generating recovery gas

摘要

PROBLEM TO BE SOLVED: To level a generated flow rate of recovery gas when recovery gas including high concentration of recovery components separated from mixed gas is generated.SOLUTION: In adsorption columns A, B, C stored with an adsorbent having adsorption selectivity for recovery components included in mixed gas, an adsorption process for adsorbing a part of the mixed gas to the adsorbent under pressure and a desorption process for desorbing a part of adsorbed mixed gas from the adsorbent under decompression are alternately repeated. Desorbed gas is made to flow out of the adsorption column where the desorption process is carried out with desorbed gas as recovery gas. The desorption process is divided to a plurality of unit desorption processes which are divided in execution order from a desorption starting time point and the unit desorption processes are executed at the same time at least at two adsorption columns. Desorption starting time points at respective adsorption columns are made to be different from each other so that the execution order from the desorption starting time point of respective unit desorption processes executed at the same time are different from each other. Insides of respective adsorption columns under execution of the unit desorption process are independently decompressed so as to be not communicated with each other.