Double-Cone valves:
As dust collects inthe hopper, the weight of the dust pushes down the counterweight of the top flap and dustdischarges downward. The top flap then closes, the bottom flap opens, and the materialfalls out. This type of valve is available in gravity-operated and motorized versions.

Rotary Airlock valves:
The valve is designedwith a paddle wheel that is shaft mounted and driven by a motor. Therotary valve is similar to a revolving door; the paddles or blades form an airtight sealwith the housing, and the motor slowly moves the blades to allow the dust to dischargefrom the hopper.

Screw Conveyors:
After the dust leaves the discharge device it is transported to the final disposal destinationby screw conveyers. Screw conveyors can be used as dischargedevices when located in the bottom of the hopper oras a separate conveyor to move dust after it is discharged. Screw conveyers employ arevolving screw feeder to move the dust through the conveyor.