Technical article

PSA N2 Generators adsorber mats and carbon molecular sieve


After using the PSA nitrogen generator for a certain period of time, there may be many reasons for N2 production efficiency. If equipment reasons are excluded, then the carbon molecular sieve inside the nitrogen generator has degraded its N2 production efficiency. If this is the case, we need to replace the carbon molecular sieve in the nitrogen generator.
One customer purchased our carbon molecular sieve at the end of last year, and last month they needed us to customize a few adsorber mats for them. When we saw the size provided by the customer, which exceeded a diameter of 2 meters, we thought it must be used for large steel, coal mines, or chemical plants. See below photos, and customer is very satisfied with them. So, what does the adsorber mats and carbon molecular sieve play in the nitrogen generator? And how to replaced?


Firstly, in the PSA nitrogen generator, carbon molecular sieve is the core component, which is mainly loaded in towers A and B of the nitrogen generator. The two towers cycle alternately during adsorption and decompression. Based on the following figure, we can see that the higher the adsorption pressure is, the greater the adsorption capacity of carbon molecular sieve for oxygen. Therefore, carbon molecular sieve selectively adsorbs molecules larger than its molecular diameter, thereby achieving the effect of separating nitrogen and oxygen.
So, what role does the adsorber mats play in the nitrogen generator?

Firstly, the adsorber mats has good breathability and excellent elasticity and toughness. In this way, when installed inside the adsorption tower, the adsorber mats can effectively and tightly adhere to the edge of the adsorption tower, ensuring that the carbon molecular sieve will not leak during the operation of the nitrogen generator.
Next, I will briefly introduce the steps for replacing carbon molecular sieves:
1. it is necessary to stop the compressed air supply and cut off all switches and power sources of the entire nitrogen generator equipment.
2. it is necessary to empty out the previous old material carbon molecular sieve and use a vacuum cleaner to suck out the crushed old material and powder inside.
3. When loading, better lay a layer of adsorber mats at the bottom of towers A and B of the nitrogen generator, and then lay a layer of 5-10cm activated alumina, mainly to buffer water absorption, protect carbon molecular sieve and airflow distribution. If conditions permit, it is also necessary to lay a layer of adsorber mat on the activated alumina to separate gases.
4. Load the carbon molecular sieve all the way to the top of the packing tower. At this time, a vibration pump is needed to compact the carbon molecular sieve inside the adsorption tower. Only with this way, the carbon molecular sieve can be filled tightly. Thus the replaced carbon molecular sieve will not sink or be easily crushed after stamping in the later stage.
5. After filling, reset all equipment and parameters. After running the machine overnight, observe the nitrogen production effect the next day.
OIM Chemical is a professional manufacturerin the production of adsorbents such as molecular sieves. If you have any questions for them, please feel free to discuss with us at any time via

+86 799 6666455

+86 18179910932
Tracy Chen
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