Questions about the pulverization of molecular sieves
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The molecular sieve in our factory has begun to disintegrate, as the problem with the adsorbent in the central part is quite severe; it is preliminarily believed that this is due to a design flaw in the air flow distributor. Are there any other factors at play? How can this situation be improved? Could someone give me some advice? Thank you
Based on your description, the air flow distributor should be a major factor, but it is also related to the performance of the molecular sieve. Logically, in order to ensure the efficiency and service life of the adsorbent, suppliers of pressure swing adsorption equipment provide users with appropriate air flow distributors; however, there are significant differences among manufacturers in terms of the design quality of these air flow distributors. Some manufacturers do not design the air flow distributor in a very effective manner, which prevents proper even distribution of air flow; as a result, the adsorbent gradually deteriorates into powder. Once it reaches a certain degree of degradation, the adsorbent needs to be replaced. I also conducted relevant research earlier; the molecular sieves and air flow distributors, among other key technologies developed by Peking University Pioneer, enjoy a very good reputation in the industry, which is one of its strengths. Their air flow distributor has been specially optimized to ensure even distribution of airflow through the molecular sieve layer, and this technology is relatively mature. As for how to solve this problem, you can ask the manufacturer whether they offer renovation services for air flow distributors I’m not quite sure either
Due to the effect of wall flow, it is generally believed that pulverization starts from the periphery. Does the author mean that the problem is more severe in the central area as a result of the uniform pressure impact from above? Factors contributing to pulverization: air flow velocity (inlet velocity, pressure equalizing return air velocity, etc.), the packing density of the molecular sieve, and the strength of the molecular sieve. Improvement measures: improving air flow distribution (either at the bottom or at the top), using ceramic balls to cushion the impact of air currents, and applying external compression. The above are my personal opinions for reference only.
Design of the adsorption tower: Is the flow rate too high? . . .
The wall effect and the jet at the center still have a significant impact on the adsorbent...
I’ve learned that the internal design of the adsorber is really important~ If one doesn’t have a good understanding of the VPSA process, then the result will be poor quality~
This post was last edited by Voyager on 2012-12-29 at 16:00. How long has your molecular sieve been in use? What are the adsorption pressure and desorption pressure? What is the air intake volume? What size is your device? I work with molecular sieves; maybe we can talk about it! You can send an email to jlchemgly@163.com
Is it not described clearly enough? Or rather, I didn’t fully understand it! Why do molecular sieves generally become powdered? It could be 1. the molecular sieve was not installed tightly, resulting in abrasion and pulverization by the airflow; 2. the design is indeed unreasonable, with issues in airflow distribution; 3. the molecular sieve does not have sufficient strength. 4. Other usage issues, such as water intake! Soak it in other impurities! The reasons and solutions depend on the working conditions and actual situation at your site!