Pressure swing adsorption-type gas separation method and separation apparatus

A pressure swing adsorption-type gas separation method, which separates a component which is easily adsorbed by an adsorbent and a component which is not easily adsorbed by the adsorbent, from a feed gas which includes at least two kinds of components, with adsorption columns, wherein

• the adsorbent is filled in the adsorption columns, and the adsorbent has strong adsorbability with respect to at least one kind of component included in the feed gas, and also has weak adsorbability with respect to at least one kind of other components included in the feed gas, and
• a temperature of the adsorbent which is filled in the columns is maintained to be higher than the highest temperature of an ambient temperature around the adsorption columns, which is variable throughout the year,
• wherein the adsorption columns are structured with a lower column and an upper column, and a temperature of the upper column is controlled to be less than a temperature of a lower column.