I currently have an application that requires the conveying of a very fine (<900 micron max but mostly <50 micron) acrylic polymer powder. The powder is very fine and free flowing but easily shears if rubbed together due to the low softening point ( glass transition of -10 degrees C ). The problem we have is that the product tends to fuse and clump in our blow through rotary valve at the knife tips and at the rotor ends, fouling our product with large (1-5mm) fused particles. Increasing the knife tip clearances is not an option as the blow back with this very fine powder causes other issues and the rotor clearances at the ends are fixed. I also suspect that the blower may be dusting the product in the rotary blow chamber as the powder is entering further exacerbating the problem.

Does anyone have any experience with this type of problem??

I am looking at installing a venturi system as a last resort as this is a very expensive way of going about it due to the capacity requirement of our system. ■