How long does the service life of carbon molecular sieves last?

How long does the service life of carbon molecular sieves last?

The service life of carbon molecular sieves is usually around 5 – 10 years, but the actual service life is affected by various factors. The specific factors are as follows:

1.The quality of the raw gas
If the raw gas contains a lot of impurities, such as dust, oil, water, etc., it will reduce the adsorption capacity of the molecular sieve, thereby shortening its service life. For example, when oil enters the molecular sieve, it will cover the surface of the molecular sieve and block its micropores, preventing it from adsorbing nitrogen normally.
The content of acidic gases such as carbon dioxide and sulfides in the raw gas is too high, and they will also react chemically with the molecular sieve, resulting in a decline in the performance of the molecular sieve.

2. Operating conditions
The pressure and temperature during adsorption have a significant impact on the service life of the molecular sieve. Excessive pressure or low temperature may cause the molecular sieve to over-adsorb and be difficult to fully desorb, thereby reducing its adsorption performance; conversely, low pressure or high temperature will affect the adsorption effect and cause the nitrogen purity to decrease. Generally, the operating pressure of the PSA nitrogen production system is 0.6 – 0.8 MPa, and the adsorption temperature is 30 – 40℃.
The adsorption time and cycle also need to be reasonably controlled. If the adsorption time is too long, the molecular sieve will be saturated with adsorption, affecting the purity of nitrogen; if the cycle is too short, the molecular sieve will frequently adsorb and desorb, accelerating its aging.

3. The maintenance condition of the equipment
Regular maintenance and upkeep of the equipment, such as timely replacement of filters and checking the sealing performance of valves, can help extend the service life of the molecular sieve. If the equipment has leakage, valve failure, etc., it will cause the system to operate unstably, affecting the efficiency and lifespan of the molecular sieve.
Starting and stopping the equipment in accordance with the correct operating procedures and avoiding shock to the molecular sieve due to improper operation. For example, when starting, the pressure should be slowly increased to avoid sudden pressure rise causing damage to the molecular sieve.

If the quality of the raw gas can be strictly controlled, the operating conditions can be reasonably adjusted, and the maintenance and upkeep of the equipment are done well, the service life of the PSA nitrogen production molecular sieve can be close to 10 years or even longer; conversely, if the above factors are not controlled properly, the service life of the molecular sieve may be shortened to less than 5 years or even shorter.