Dust Collection & Pollution Control Q&A
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We have a small, 13 cu ft ribbon blender used to mix three powders. We use it about once a month. Powder gets all over the floor when dumping the bags into the mixer and when bagging the finished product. How can we clean up the powder on the floor and how can we prevent it from happening in the first place?Answered September 22nd, 2010 by Expert:For the fugitive dust issues associated with the loading and unloading process, a good solution is a source capture dust collection system.
The source capture design for the loading process will include a sack tipping station with back draft hood. The station is basically an enclosure with a hinged door to feed material into the blender. A grate is provided in the chute to eliminate the risk of dropping the open bag into the blender. The unit can be mounted above the blender or mounted at ground level with a hopper and a flexible screw conveyor to transfer the material into the blender. The extraction volume should be sized for a face velocity between 150 - 200 FPM in the open door area. These stations are marketed with an integral dust collector including centrifugal fan. If any of the powders are combustible, then my recommendation is to pipe the back draft hood to a dust collector with proper safety equipment located on the exterior of the plant.
On the bag filling application, a source capture hood can be mounted to the blender outfeed. This perimeter hood will be slightly larger than the bag size and the extraction volume will be in the range from 600-1,200 SCFM for non-toxic powders.
By installing a properly designed source capture system, the housekeeping issues will be mitigated.



