| Oxygen is an important commodity chemical, which has numerous applications in steel making, nonferrous metal smelting, wastewater treatment, medical and military purpose and so on. About 20% of air separation is presently accomplished by pressure swing adsorption technology, and it has more and more promising future for pressure swing adsorption to product oxygen from air. The main aim in the industrial application of pressure swing adsorption of air separation for O2 were to reduce power consumption and improve production scale. So attentions were paid on high property adsorbent development and process improvement during the past 40 years. Modeling was taken into account in decade recently. Concentration and temperature profiles in bed and their effects on process cycles could be attained by model computation, In the meantime, the influence of process procedure and condition on 62 purity, recovery and productivity could also be investigated conveniently in this way to achieve process optimization and power reduction. But model calculation was still in developing presently and the optimization and analysis of different process of air separation (VS A and PSA) and process conditions was scarce. Therefore, it is important to study on the process conditions and their correlation of various adsorbents, optimization and analysis of different conditions by using modeling computation in order for the better design of air separation for O2.In this paper, the adsorption equilibrium of N2 and O2 on CaA zeolite was investigated firstly by the dynamic breakthrough experiment. The adsorption equilibrium equations of N2 and O2, which were expressed by the loading ratio correlation (LRC), and model parameters related to temperature were obtained by using these adsorption equilibrium data. The heat of adsorption of N2 and O2 were 21.98kJ/mol and 13.67kJ/mol, respectively. The results showed that LRC could reflect the adsorption equilibrium relationship between N2 and O2 on zeolite reasonably, and the reliable parameters could be provided for process calculation of oxygen product by air separation. In the meantime, temperature profiles of bed were investigated in adsorption and decompression procedure by the adiabatic experiment and the coincidence between temperature wave and concentration wave was observed. Adiabatic experiment revealed the relation between temperature wave andconcentration wave in bed and showed that pressure swing adsorption of air separation for O2 product was a non- isothermal process.Secondly, pressure swing adsorption of air separation was calculated and analyzed based on mathematical models, which fully considered the mass-transfer, heat-transfer and momentum-transfer of non-isothermal process. The mathematical models consisted of axial dispersed plug flow models of fluid, energy balance models of gas-solid and bed wall, adsorption equilibrium model of LRC and mass transfer model of LDF(the linear driving force), which was designed for six-step cyclic process(feed repressurization, adsorption, cocurrent depressrizing pressure equalization, counter-current depressrization or evacuation, product purge and countercurrent pressuring equalization). Based on the differential algebraic equations, which was transformed from the partial differential equations of models by orthogonal collocation method, and Besirk differential algebraic equations solver, the programs of non-isothermal pressure swing adsorption process were complied by FORTRAN. CaA-VSA, LiX-VSA and CaA-VSA process were computed and the sensitivity of factors were analyzed, considering the demands of design (3000Nm3/h, 93%O2). The results were as follows: (1) The oxygen recovery and energy consumption (power) of VSA process were coincided with the actual process closely, which verified that the models, calculated method and model parameters were chosen suitably. The necessity of pressure equalization and product purge after evacuation step were confirmed by concentration and temperature variation in bed using model calculation. (2) CaA-VSA...
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