Nitrogen, which is naturally present in the atmosphere, is a gas that is widely used by industry in many areas: laser cutting, modified atmosphere conditioning, inertization, etc. It is known, in particular, for its action against certain tumors, as well as as an insecticide and as a processor cooler. However, special devices are required to produce this gas. To fully understand them, here's what you need to know about how a nitrogen generator works.
Nitrogen generator general operation
The surrounding air is 78% nitrogen. To get access to this natural resource and use it, it is necessary to isolate it from other components of the atmosphere: oxygen, moisture, dust ... This is the very principle of operation nitrogen generator, which allows companies to produce the nitrogen they need locally. from the surrounding air. There are two main types of nitrogen generators: PSA nitrogen generator and membrane nitrogen generator.
PSA Nitrogen Generator
The PSA generator (for pressure swing adsorption, i.e. variable pressure separation) allows the production of nitrogen from ambient air. This device consists of two tanks filled with a molecular sieve (in this case, activated carbon). Applying variable pressure to these tanks separates the various gases present (nitrogen, oxygen, argon, and noble gases).
In particular, applying pressure leads to filtration of nitrogen with activated carbon. This pure gas is then released at the generator outlet, while oxygen, carbon dioxide, or even water vapor is adsorbed (i.e. bound) to the activated carbon. After the first tank is saturated, the process continues in the second tank. The gas adsorbed in the first tank is then released into the atmosphere. Electronic control allows you to repeat this cycle. When one of the tanks is adsorbed, the pressure in the other tank drops to allow it to regenerate.
Membrane Nitrogen Generator
Like the PSA generator, the membrane generator uses ambient air to produce nitrogen. However, it works on a completely different process. The membrane generator separates the various components of the atmosphere using a bundle of hollow fibers. Especially compact, these fibers are present in the generator in very large quantities. Consequently, it is able to process air much faster than a PSA generator.
More specifically, the air enclosed in this type of generator passes through the membrane along hollow fibers. Then oxygen, water vapor and other gases contained in it are released from it, while nitrogen remains a prisoner of the membrane. This pure nitrogen is then collected at the output of the device.
Whether they are driven by a membrane or by a variable pressure boost, both types of generators allow you to produce pure nitrogen ready for use. However, the PSA generator is best suited for applications requiring the highest standards of cleanliness.