The PSA oxygen-generation molecular sieve always turns into powder within half a year; I’m looking for a molecular sieve that can be used reliably
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This project involves a small PSA oxygen generator with an output of 5–30 cubic feet per hour. The molecular sieves currently in use have low oxygen production efficiency when using large particles, while those with small particles tend to turn into powder easily. I would appreciate some guidance from those who know more, thank you.
What brand do you use? I know that for the air separation units I’ve worked on, UOP is the brand used
Could it be that the molecular sieve wasn’t filled properly when filling it, which caused the molecular sieve to become powdered?
There are many reasons for the pulverization of molecular sieves, such as issues related to the strength of the molecular sieves themselves, improper process design, and operational problems. As you said, the oxygen production capacity of larger particles is certainly lower than that of smaller particles; this is determined by the properties of the molecular sieve as well as the rationality of the process design. However, this issue can be effectively resolved through improvements.
Regarding the problem of powder formation, I think you are using particles that are very small; a mesh size of 12*20 is typical for use in small-scale oxygen production systems. Such molecular sieves are prone to issues such as leakage or spraying, which can further lead to powder formation； Another point is that the pressure in PSA should be controlled at around 5-6 KG, as estimated based on your equipment; with small particles, it’s difficult to maintain proper compression, and friction can lead to particle fragmentation. Therefore, it is still recommended to use large particles for oxygen generation equipment. If you have any questions, please contact us by phone.
Does the equipment have a molecular sieve compression device? If not, as long as the molecular sieve is not installed tightly, powdering is inevitable!
Firstly, choose products of good quality; of course, they are more expensive. Secondly, the manufacturing process plays a significant role – factors such as whether there is constant moisture present, whether the activation temperature is too high, or whether there is excessive airflow impact, as well as issues with the packing itself and an inappropriate selection of the product, are all problems in my opinion
Where did you buy the oxygen generation equipment? I work in the field of oxygen generation equipment; you can get in touch with me.
Not enough filling? Leaking cylinder? Incorrect selection? Operation issue? No carbon site alarm?
For loading and machine compatibility, the strength of the molecular sieve needs to be considered from three aspects. 1 The most important thing is proper packing; if the packing isn’t adequate, no molecular sieve can withstand it. If the coordination is not optimal, it is also possible to consider using high-strength molecular sieves or activated alumina for partial filling at the air inlet in order to buffer the airflow. 2 The first intake of air after startup is very important; it’s best to allow a small flow of air in first, then gradually increase the flow over several cycles before operating at normal levels. Prevent direct impact of atmospheric currents on loosely packed materials from causing a vicious cycle of powdering. 3 Replace it with a better molecular sieve. UOP’s or CECA’s products are more reliable than most domestic ones.
There are many reasons for the pulverization of molecular sieves, including the strength of the molecular sieves themselves, the way they are packed, the manufacturing process, and the quality of the air used for compression. It is recommended that the person in question consult a professional to conduct an inspection and identify the cause, so that appropriate measures can be taken.