Which nitrogen generator is right for my application?
Do you want complete independence from nitrogen suppliers? Then you cannot avoid your generator. These devices extract valuable gas from dry compressed air by removing the oxygen molecules. Here you can find out which processes the nitrogen generators work with and which variant is best suited for your application.
Nitrogen generators: this is how they deliver valuable gas
There are three generation methods, of which usually only two are possible. Because a cryogenic air separation plant is a huge piece of technology that is more likely to be seen in gas suppliers than in companies that produce for their use. In addition to the space requirements, the operational and safety requirements are also significantly higher.
But there are also variants "for domestic use": pressure swing adsorption (PSA) and membrane technology.
Producing nitrogen with PSA generators
The abbreviation PSA is derived from the English term "Pressure Swing Adsorption". In this process, the nitrogen generator separates the valuable gas with a special carbon sieve (a so-called carbon molecular sieve or CMS) from the air supplied.
This works relatively simply because the unwanted molecules collect in the sieve, while the nitrogen is concentrated upstream and enters the storage container. After the sieve has reached a certain level of saturation, it is “rinsed” and is ready for the next cycle in the nitrogen generator.
With this technology, gas with high purity (95 to 99.999%) can be generated, which is used in the following applications:
- Food and Beverage industry
- Metal and plastic processing
- Pharmaceuticals
- Oil and Gas
- Appliance Manufacturing
- Cable Manufacturing
A PSA nitrogen generator can be operated around the clock thanks to the monitoring system, as this controls the gas quality and issues warning messages if the values fall outside the box. In addition, the higher efficiency of this technology is reflected in a better air factor, ie the ratio of compressed air used to nitrogen generated.
Membrane generators to produce nitrogen
Nitrogen generators with membrane technology also have a simple function and only need dry compressed air as a raw material. As the name suggests, this is passed through a membrane module, where the air molecules penetrate the membrane fibers. Water and oxygen rush through the fibers to the discharge opening relatively quickly, while nitrogen and a residue of argon make themselves comfortable.
A nitrogen generator comprises several membrane modules, each with its air inlet openings and separate outlets for the nitrogen and the so-called permeate, i.e. the undesired air components.
Due to its smaller footprint, faster start-up, and quieter operation, this technology is more suitable for an open installation where people are still working. In addition, the simple functional principle causes lower maintenance costs.
However, the simplicity is at the expense of the possible degree of purity (90 to 99%), so the membrane nitrogen generators are used more "for the rough", for example:
- Fire protection
- Tire inflation
- Oil & Gas Industry
Conclusion
In summary, it can be said that both technologies for nitrogen generators are justified. Ultimately, it depends on the degree of purity of the nitrogen you want and what your requirements are for the capacity and ease of maintenance of the system.