A six-step, two-bed dual-reflux pressure swing adsorption process for air separation using LiLSX zeolite was first developed and studied systematically. Then two original integrated vacuum pressure swing adsorption processes were well designed ground on the analysis of the mass transfer behavior in the adsorption column, in order to overcome some difficult obstacles that exists in a dual-reflux process, such as low processing capacity and high energy consumption. The performance comparison results show that the adsorbent productivity of dual-reflux process, integrated process I and process II were 17.436, 34.007, and 36.741 NLO2/(kg h) and the energy consumption of those were 1.897, 0.681, and 0.762 kW h/Nm(3)O(2), respectively. Accordingly, for integrated process I and process II, performance parameters of processing capacity and adsorbent productivity are almost twice than that of a dual-reflux process, yet energy consumption is only one-third that of a dual-reflux process. Then in-depth discussions for these results were analyzed in detail and comparison between two integrated vacuum pressure swing adsorption processes and dual-reflux process and comparison of two different integrated vacuum pressure swing adsorption processes themselves were also investigated systematically.