The two ways to get nitrogen
Delivered nitrogen arrives as cylinders, packs or a liquid dewar. On-site generation separates nitrogen from compressed air using a pressure swing adsorption or membrane system. The choice is less about technology preference and more about how the gas is used.
| Situation | Usually favours |
|---|---|
| Low, intermittent consumption | Delivered cylinders - the capital stays with the supplier |
| Steady daily consumption across shifts | On-site generation, where the capacity is used most hours |
| Purity requirement that varies by line | On-site generation, where purity can be set per process |
| Site with limited storage or handling capacity | On-site generation, no cylinder store or changeover |
| Remote site, long delivery lead time | On-site generation, subject to power and maintenance cover |
Purity is a cost decision
Higher purity costs more air and more energy per unit of nitrogen, so specifying the highest grade for the whole plant is usually wasteful. Set the purity each process actually needs, and where a line needs a higher grade, treat it as a separate requirement rather than lifting the whole system.
The compressor behind the generator
A generator is only as good as the air fed to it. Oil, water and particulate have to be removed before the separation stage, and the feed flow and pressure have to be stable. That means a dedicated dryer and filter chain, sized for continuous duty rather than intermittent workshop use.
What to specify
Required purity, flow, whether demand is continuous or batch, available power, and the space and maintenance capability on site. Those answers decide whether generation is the right answer at all.
Send us your working pressure, required flow and site conditions and we will propose a configuration. Contact OPPAIR.