Nitrogen makes up 78% of the atmosphere on earth with oxygen making up just 21%. Nitrogen gas is used in many industries such as mining and food packaging. For many of these industries to function as is required, they need a constant supply of nitrogen gas.
A lot of companies choose to use nitrogen cylinders to get the gas they require to perform their industrial operations. However, nitrogen cylinders are very expensive and can be quite a hassle. If the delivery does not go as planned, factory processes may not go as smoothly as intended which usually has knock-on effects through the process and ultimately hits the consumer in price rises or slower demand. It’s for these reasons that many businesses are turning to a nitrogen generator for their business.
Nitrogen generators are a common type of equipment that is widely used by factories across the world to create nitrogen gas inside the factories to make sure the supply of nitrogen is unlimited whenever needed.
Organisations can either use a PSA nitrogen generator or a membrane nitrogen generator.
PSA Nitrogen Generators
PSA stands for Pressure Swing Adsorption. PSA nitrogen generators operate using the PSA concept to produce a constant supply of nitrogen gas from the oxygen molecules in compressed air.
How PSA Nitrogen Generators Work
A couple of towers are filled with a sieve-lined vessel known as carbon molecular sieve (CMS). CMS is different from other activated carbons because its range of pore openings is very narrow.
Compressed air goes in from the bottom tower and through the CMS where the lining adsorbs small oxygen molecules while allowing nitrogen molecules to proceed to the receiver.
The narrow pore openings allow for oxygen molecules to penetrate, thus separating nitrogen molecules which are too large to enter the CMS, from the oxygen molecules.
The larger nitrogen molecules then emerge as the final product.
After a set time, the tower switches to regenerative mode automatically thus venting contaminants from the CMS.
Through this method, the final purity level of nitrogen generated by a PSA generator usually ranks at 99.9995%, which is slightly more than the nitrogen purity level of between 95 to 99% acquired by a membrane nitrogen generator.
Membrane Nitrogen Generators
The working principle of membrane nitrogen generators involves the compressed air getting filtered and passing through certain technically developed membranes.
These membranes have hollow fibres that operate in a similar way as reverse fibres. They simply separate nitrogen molecules from compressed air through permeation. The number of membranes in a membrane nitrogen generator system decide the purity level of the nitrogen extracted. Different sizes of the membranes dictate both the increasing and decreasing pressure and thus affect the nitrogen purity level as well.
These two types of nitrogen generators have found their ways into some of the biggest companies and help to ensure that processes run smoothly and efficiently.