What are the reasons for frequent material carrying in the dry twin screw system and the discharge of defective materials, and what are the solutions?
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On the drying line of our factory, the two spinners frequently carry material; it’s necessary to clean them once a month, otherwise material will get scattered at the exhaust end. With the same formula, some lines don’t drift while others do. Has anyone encountered this same problem? And how did you solve it? Thank you!
Wind pressure, air volume, separator structure, operation
This post was last edited by Yongbu※Yanqi on March 13, 2017, at 23:53. On our factory’s drying line, the secondary cyclone frequently carries material along with it; otherwise, material would be discharged from the exhaust outlet. I believe the reason for this is that the particle size of the resin resulting from the polymerization process is relatively small. This has little to do with the fans or human operation. When the material is floating, is there an analysis to determine if there is a lot of fine resin particles? It turns out that with a fluidized bed, especially when adjusting or replacing the dispersant, it is easy for fine particles to drift out through the exhaust chimney.
The resin particle size can’t be the only main reason, because in the other line there is no material drifting around. The outlet air pressure varies by only about ±0.5 kPa across both lines. The physical and chemical properties of the samples produced are all within the specified limits. Is it possible that there is a leak in the cyclone separator, causing the material to be carried away by the wind?
Could it be that there’s a leak inside the separator, which is causing this situation?
If the formulas for the two lines are the same, then it shouldn’t be due to the material being too fine. Where does the material for the two-spin extractor come from?
Is the cyclone separator clogged?
The formula is the same, but is the actual amount of dispersant added the same? Has the scale of the dispersant weighing tank been calibrated? Or a flow meter. There are also single-flow meters. It’s best to grade and sieve the resin to check the particle size distribution and see if the two curves are identical.