The service lifetime of molecular sieves
User£ºadmin AddDate£º2015/3/27 Read£º6442Times
The service lifetime of molecular sieve has a great relationship with working conditions of application, such as the size of the dryer, activation methods, regeneration cycle, maintenance, regeneration methods, the water content of the dried material, the dried material whether easy aggregation or not, and so on. A well-designed, properly used molecular sieve adsorption device, its life should be between 24,000-40,000 hours, which is about 3-5 years.
The service lifetime of molecular sieve in different devices
1, Air separation unit, 8-10 years
2, Petrochemical gas separation unit, 3-5 years
3, Natural gas processing unit, 5-8 years
4, Liquid product drying device, 1-3 years
5, General pyrolysis gas dryer, 3-5 years
6, Hydrogen dryer, 7-8 years
The method of extending service lifetime for molecular sieve is proper use and maintenance of molecular sieves. Molecular sieve adsorption process, it should be strictly operated in accordance with the design value of adsorption equipment, key indicators such as flow, temperature, pressure, system switching time should not arbitrarily change.
Enclosed: The influence factors of adsorbent service lifetime in nitrogen PSA device
One is crushing problem, the other is the permanent absorption problem. It will become permanent adsorption, can¡®t been desorbed when silica gel is in the saturation adsorption of oil, saturated hydrocarbons, etc. This also known as "poisoned." The flow has more oil will shorten the life of the silica gel.
The reason causing broken:
The strength of the adsorbent itself;
Airflow (or liquid) impact and shock loading is too violent caused by not closely packed, so adsorber regeneration switching valve should switch slowly;
Heated gas moisture content;
Regeneration temperature is too high, at above 240 ¡æ, silica gel will be damaged;
Water into adsorber can also cause silica gel broken;
After many times of alternating adsorption temperature and regeneration temperature, silica gel (or molecular sieves) also will be broken.