What Is a Nitrogen Generation System and How Does It Work?

Across many industrial, manufacturing, food, and research applications, a nitrogen generation system is a backbone utility: it delivers a continuous supply of nitrogen gas exactly on-site, on-demand. Whether you’re preserving freshness in packaging, maintaining inert atmospheres for welding or brazing, or ensuring safety in oxygen-sensitive processes, using an in-house nitrogen generation system can offer reliability and cost savings that bottled or delivered gas often cannot match.

In this article, we’ll explain what a nitrogen generation system is, explore how nitrogen generation systems work, and show you the main types and benefits of installing one.

What Is a Nitrogen Generation System?

A nitrogen generation system (also called a nitrogen generator) is a setup that extracts nitrogen gas from the ambient air, purifies it to a required purity level, and delivers it for use in-house. Instead of ordering nitrogen in cylinders or bulk deliveries, the system makes nitrogen continuously at your facility, customized to your usage rate and purity needs.

Key components typically include a source of compressed air, filters and dryers to remove moisture, particulates, and oil, the separation module where nitrogen is isolated, and controls, safety features, and sometimes storage or buffer tanks.

How Does a Nitrogen Generator Work?

There are multiple technologies for separation, and each nitrogen generation system might use one or more different methods depending on required purity, flow rate, pressure, and cost. Two of the most common technologies are PSA (Pressure Swing Adsorption) and membrane separation.

PSA systems pass compressed air through vessels filled with an adsorbent like carbon molecular sieve. Oxygen, along with CO₂ and water vapor, is adsorbed under high pressure while nitrogen passes through. The pressure is then released so the adsorbent regenerates, and the cycle alternates between two or more vessels to provide continuous output. PSA can deliver very high purity levels, often exceeding 99%.

Membrane systems push compressed air through a membrane that allows oxygen and water vapor to pass through faster than nitrogen. The slower nitrogen flow is collected as product gas. While membrane systems typically achieve 95–99% purity, this is often sufficient for many industrial applications.

Here is a step-by-step summary of how a typical PSA nitrogen generation system works:

1. Air intake & compression – Ambient air is drawn in and compressed to a target pressure.
2. Pre-treatment – Filtration, drying, and cooling remove moisture, oil, dust, and CO₂.
3. Adsorption – Cleaned, compressed air enters a vessel filled with carbon molecular sieve. Oxygen and other unwanted components are captured while nitrogen passes through as the product.
4. Switching / Desorption – Once the adsorbent becomes saturated with oxygen, the system directs air to another vessel while the saturated vessel regenerates by reducing pressure, releasing the oxygen.
5. Purity control & buffering – Sensors monitor nitrogen purity, and buffer tanks or storage smooth out fluctuations in demand.
6. Delivery – Purified nitrogen is delivered to the point of use or stored if needed.

Types of Nitrogen Generation Systems

Different configurations suit different needs. Options include turnkey PSA generator systems, membrane nitrogen generators for lower-purity applications, custom engineered systems for unique requirements, containerized or modular systems for portable operations, and cylinder-filling systems for facilities that want to fill their own nitrogen cylinders.

Why Choose a Nitrogen Generation System?

Key benefits include cost savings compared to bottled or bulk nitrogen, supply reliability with independence from delivery schedules, the ability to set and maintain exact purity levels, and operational flexibility to match changing demand. Additional advantages include fewer safety and handling risks and a reduced environmental footprint thanks to less transportation and packaging waste.

Contact On Site Gas Systems For Your Nitrogen Gas Needs!

Ready to bring the benefits of on-site nitrogen generation to your operation? Contact On Site Gas Systems today to discuss your specific N₂ generator needs. Our team will help you evaluate your nitrogen requirements, recommend the right system for your application, and guide you through every step—from design and installation to ongoing support—so you can enjoy a reliable, cost-effective supply of high-purity nitrogen on demand.