Oxygen generators for the production of high-purity nitrogen (N2) from air

Oxygen is required for various industrial processes. It is mainly used in the production of pig iron and steel, in copper refining and in the partial oxidation of coal and heavy oil. In addition, O2 is used for oxidation in chemical syntheses such as the production of various acids (acetic acid, nitric acid, sulfuric acid), acetylene or ethylene oxide. Oxygen also serves as the starting material for the production of ozone. Oxygen can either be purchased in gas cylinders or generated on-site by a gas generator.
Providing oxygen by purifying ambient air on-site offers several advantages:

  • No transportation costs.
  • Oxygen can be fed in directly.
  • Oxygen supply can be adjusted anytime according to demand.
  • A reliable supply avoids delivery bottlenecks.
  • No dependence on external suppliers thanks to self-sufficiency.
  • Lower oxygen costs
  • Payback within a few years
  • More sustainable for the environment
PSA Oxygen Generator

To separate nitrogen and thereby purify oxygen (O2) from air, the so-called Pressure Swing Adsorption (PSA) method is used. This is a physical process that exploits the different adsorption properties of gases at different pressures to separate them. Depending on the implementation, the removal of other gases such as carbon dioxide can also be achieved. To separate nitrogen and generate high-purity oxygen, nitrogen-affine materials such as zeolite molecular sieves (ZMS) are used. The gas mixture (air) flows through the molecular sieve designed for this application at a certain pressure. Due to the stronger interaction of nitrogen with the molecular sieve, nitrogen is retained there. The second gas (oxygen) is not adsorbed and thus leaves the system in an enriched form. Once the molecular sieve reaches its capacity limit, the gas flow is redirected to another molecular sieve. By reducing the pressure, the interaction between the molecular sieve and nitrogen weakens significantly, allowing the sieve to be regenerated and used again for purification. The system is controlled by a Programmable Logic Controller (PLC), which enables continuous purification.

Advantages

  • Stable gas production through a quasi-continuous process
  • Fully automatic system
  • Small footprint and easy operation: the system is operated from the front side.
  • The generator is characterized by low power consumption and operating costs
  • Design and configuration can be adapted to customer requirements within certain limits
  • Purities of 91–95% can be achieved depending on the configuration
  • Gas flows from 5–1500 N m3/h can be achieved depending on the configuration
  • Full CE certification
PSA Oxygen Generator

Crystec looks forward to building a cost-effective system for you that meets your most demanding requirements.