01 How Does a PSA Nitrogen Generator Work?

1. Air Preparation and Purification
Raw air first enters an air compressor and is compressed to a certain pressure (typically around 0.8 MPa). The airflow then passes through a purification system consisting of a refrigerated air dryer and filters, which thoroughly removes moisture, impurities, and oil, ensuring that the air entering the adsorption towers is clean and dry.

2. Adsorption and Desorption
The clean compressed air enters the bottom of the adsorption tower, where it is evenly distributed by a flow diffuser. Under pressurization, the carbon molecular sieve preferentially adsorbs oxygen, while nitrogen passes through the adsorbent bed and exits from the top of the tower.

At the same time, the other tower (the regeneration tower) rapidly depressurizes and introduces a small amount of product nitrogen for reverse purging, forcibly “displacing” the adsorbed oxygen from the pores of the carbon molecular sieve and venting it out, thus restoring the adsorbent’s capacity.
The two towers alternate between adsorption and desorption in a cyclic manner, achieving continuous nitrogen production.

3. Nitrogen Purity Adjustment
The control system precisely adjusts the cycle time and pressure of the adsorption towers to stably control nitrogen purity. Currently, PSA nitrogen units can produce nitrogen with a purity as high as 99.999%.