Used 25,000 SCFH (670 Nm3/hr) PSA nitrogen plant built on the basis of Air Products PRISM PSA technology. Product pressure 85 PSIG (6.0 Kg/cm2), purge pressure 22 - 24 PSIG (1.5 - 1.7 Kg/cm2), PSA maximum bed pressure 99 - 110 PSIG (7.0 - 7.7 kg/cm2). Product purity: 0.5% oxygen. The plant has an Atlas Copco GA315-150 air compressor. Compressed ambient air is fed to the PRISM PSA System. A minimum inlet pressure of 110 PSIG is required in order to produce the designed product capacity. The compressed air then enters one of the two adsorption vessels where the oxygen and nitrogen are preferentially separated. The feed air is then switched to the second vessel where the adsorption process continues.