Okay I have a solution for you that should work with your System then.
The Pipe going to your Dust Collection Area, put a Dust Funnel set to the smallest Dust Size inbetween the production and the dust Area. That way ONLY Dusts ever make it to your Area. If you are concerned about the bandwidth use of microscopic Dusts, use 5 OreDict Filters to Filter for the 5 sizes of Dusts (Block of Dust, regular Dust, small Dust, tiny Dust, 72nd Dust).