with the flow following the arrows as indicated in fig3 as the air passes under lower vane 51 it engages with the fibers entering through opening 40 paddles 46 prevent the air from exiting chamber 26 through opening 36 as the heated air engages dries and lifts the fibers which are being delivered through opening 40 large trash particles drop out into sump 52 the fibers become entrained in the air flow and are transported out of chamber 48 through the opening connecting with conduit 24 vanes 50 and 51 are pivotal about axis 53 to move between extreme open and closed positions when vane 50 is positioned in its extreme left most position it prevents substantially all of the air flow across the upper part of chamber 48 between openings 22 and 24 when vane 50 is in this position vane 51 must be positioned in its extreme right position this allows the air to flow through the opening formed between the end of vane 51 and the end of conveyor belt 30 vanes 50 and 51 are adjusted relative to each other to allow air of sufficient volume to pass below vane 51 and engage with the fibers to heat clean and convey them when vane 50.