Unused (2) 110 TPD each VPSA Plant consists of two (2) identical process modules. The plant operation is a periodic batch process, in which adsorbent material is alternately fed with pressurized air to produce the required product, and regenerated by vacuum to remove the residual gases from the adsorbent. During the generation of oxygen, a cyclic swing between overpressure and vacuum occurs. To reduce energy consumption, the pressure is equalized between the production and regeneration steps. Each adsorber undergoes a cyclic process consisting of (1) Adsorption (O2 production); (2) Desorption (evacuation); (3)Re-pressurization (pressure build-up). VPSA plants provide great energy efficiency and flexibility to applications for furnace enrichment, oxygen fuel burners, glass manufacturing, gold bleaching, water treatment, steel mills, oxygen bleaching at pulp and paper mills, uranium recovery, and ozone generation. They are often the most cost-effective oxygen production choice up to 60 tons per day or more, providing high purity oxygen is not required.