Choosing laboratory gas generators: How to decide

When it comes to deciding which gas generator is best for your lab there are some considerations lab managers must make. There are two main technologies used to generate nitrogen from air: membrane systems and Pressure Swing Adsorption (PSA).

Membrane Nitrogen Generator Technology

As a result of selective permeation across the membrane wall, nitrogen is separated from atmospheric air. Gases that are "fast" (oxygen, carbon dioxide, and water vapor) permeate the membrane wall much faster than gases that are "slow" (nitrogen).

In the selective permeation process across the membrane wall, nitrogen is separated from the atmospheric air source. The original gas mixture is separated into two streams: the permeate and the product. As a result of the permeation process, oxygen, carbon dioxide, and water vapor are combined and vented.

Membrane technology illustration

The lower the flow rate passing through the membrane the higher the purity of nitrogen is achieved. The purity can be further enhanced by increasing the temperature.

Pressure Swing Adsorption Technology

The other option, Pressure Swing Adsorption, cycles gas at high and low pressure, flushing compressed air through a bed of carbon beads, also known as a Carbon Molecular Sieve CMS. Nitrogen molecules are allowed to pass through the carbon bed but the oxygen and carbon dioxide molecules are too large to pass through and are vented off. PSA generators can be scaled up to provide very large quantities of nitrogen gas for entire labs or for manufacturing and process industries.

PSA technology illustration

How to choose the right nitrogen generation system for your lab

So which generator should you choose?

The main decision comes down to the flow rate you require. Membrane nitrogen gas generators are able to produce a reliable source of nitrogen across a range of flow rates, but if your lab needs a much higher flow rate, while maintaining high purity levels, a PSA nitrogen generator is a better solution for your lab.

The added benefit of a membrane nitrogen generator is that they are also far more cost-effective than PSA generators.

PEAK’s Genius XE, Solaris XE and Infinity XE n2 generators

What else should I consider before purchasing a nitrogen generator?

Compressor Requirements

Labs must understand whether they require an air compressor based system or not. If a lab has an in-house supply of high quality compressed air (ISO 8573-1:2010 Class [1.4.1]) a compressor less generator will be suitable, if not a compressor based system will be needed.

Compressor based systems feature moving parts and are therefore subject to general wear and tear over time and will require servicing at regular intervals. A service contract comes highly recommended for labs with this equipment in order to avoid unplanned costs should a breakdown occur. Generators without compressors do not contain moving parts and therefore their service requirements are dramatically reduced in cost and frequency.

Does the generator meet my lab needs?

Each lab has different requirements and PEAK has a range of nitrogen generators to cater to a variety of nitrogen supply needs, including flow rates that range from 0 - 4,253 L/min, a range of output pressures up to 130psi and, as mentioned before, a range of gas purities to suit most labs.

Will it work with my current instrument?

PEAK Scientific have gas generator solutions that have been validated and approved by all major LC-MS instrument manufacturers which can give you the confidence to use a PEAK gas generator alongside your other lab instruments.

These include, but are not limited to, the Genius XE 35 and Genius XE 70 which have been approved by Agilent, the Genius XE SCI 2 and Infinity 1032 approved by Sciex, the Genius SQ24 and Solaris XE for Waters approved by Waters, and the Genius XE and Solaris XE approved by Thermo Fisher.

Does the nitrogen generator meet compliance standards?

PEAK Scientific is an ISO 9001:2015 accredited organization, covering the design, manufacture and servicing of laboratory gas generators. ISO 9001:2015 certification demonstrates our commitment to quality products and services in over 150 countries. You can read more about our dedication to manufacturing the highest quality gas generators in our compliance statement.