A system for adding dust control solution to a vertically falling first stream of a substantially dry particulate proppant, where the first stream has effective diameter, the system including a stationary, generally horizontal, deflector plate with drop-off edge, the plate mounted into the stream whereby the proppant collides with the plate and cascades from the plate around the drop-off edge to create a second stream of the particulate proppant having the general shape of the drop-off edge with a stream thickness and nozzles for spraying dust control solution into the second stream.