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Pressure swing adsorption (PSA) unit becomes an alternative and more efficient process for o xygen separation from air than the cryogenic process, because of the low power consumption, availab ility, flexib ility, fully automated operation of the process. [1] In 1932 the first unit of a single bed of the PSA process was developed by Finlayson and Sharp. In 1960, the first unit of dual bed PSA process was designed by Skarstrom for drying process. [2-8] In the last decades a lot of studies have carefully investigated the performance of the PSA unit experimentally and theoretically to improve process performance. The following modificat ions were taken into account, such as: pressure equalization step, vacuum pressurizing step, product pressurizing step, increase number of step per one cycle , increase nu mber of co lu mns, and modify adsorbent characterizat ion. A ll studies considered the effects of various process parameters. For instance : adsorption pressure, cycle time, purge flo wrate, product flowrate, break through time on the PSA process performance. Which was indicated by the product purity , recovery, and energy consumption. [9-24] Co mmercial zeolites 13X and 5A almost were used as adsorbents for air separation by PSA process. The maximu m purity is limited to 95% o xygen because of the argon presence in the air and because the similar adsorption capacities of oxygen and argon on the zeolite adsorbents.[25-27 ] Although of neuroses studies introduced about PSA p rocess , but no one focused on the comparison between different design of the PSA process to summarize the performance of each other. As a result of computer power development in the last decade, several computer programs for chemical engineerin g process are available for modeling and simu lation for deeply investigation of the dynamic behavior of the pressure swing adsorption. [13, 15-18 ] The aim o f th is study was to verify a mathematical model using experimental data for single bed adsorber fro m literature [25]. Then, the validated model will be used to design four configurations of PSA processes for co mparison such as: 2-bed 4-step with air feed pressurizing, 2-bed 4-step with p roduct pressurizing, 2bed 6-step with pressure equalizat ion processes, and 2-bed 6-step with pressure equalization processes as well as product pressurizing. Moreover, evaluation the effect of operation parameters such as purge flowrate, cycle time, and product flowrate on the process performance, and power consumptio n of each process.

A mathematical model was used to design four modes of two-bed pressure swing adsorption (PSA) process to investigate argon presence in the feed mixture. The effect of operating parameters such as cycle time, pressure equalization, adsorption pressure, and purging flow rate was investigated. The model was validated with experimental data of nitrogen separation from the air by a single bed adsorber on carbon molecular sieve (CMS). A good agreement with experimental data is obtained. In the PSA process, higher purity of nitrogen (99.7%) was detected by mode 4 when the feed mixture was free of argon (O2: 21%, N2:79%). While the nitrogen purity was only 98.0% in the state of argon presence in the feed mixture (O2: 21%, N2: 78%, Ar: 1%). The results showed that the cycle time had insignificant effect whereas the pressure equalization and purging at low vacuum pressure had a significant effect on the process performance. ABSTRAK: Model matematik digunakan bagi membina empat mod terdiri daripada tekanan dua-turus proses penyerapan buai (PSA) bagi menyiasat kehadiran argon dalam campuran pakan. Kesan parameter beroperasi seperti masa kitaran, penyamaan tekanan, tekanan penyerapan, dan kadar aliran penyingkiran disiasat. Model matematik tersebut disiasat melalui data eksperimen pemisahan nitrogen dari udara melalui penyerapan turus tunggal pada penapis molekular karbon (CMS). Data eksperimen yang bagus diperoleh. Dalam proses PSA, mod keempat menghasilkan ketulenan nitrogen (99.7%) lebih tinggi apabila campuran pakan bebas argon (O2: 21%, N2:79%). Sementara itu, ketulenan nitrogen hanya 98.0% apabila terdapat kehadiran argon dalam campuran pakan (O2: 21%, N2: 78%, Ar: 1%). Kajian menunjukkan masa kitaran memberi kesan tidak signifikan sementara penyamaan tekanan  dan penyingkiran pada tekanan vakum rendah mempunyai kesan signifikan terhadap prestasi proses.