Screw conveyors that are used in dust conveying system can be LS screw conveyor, shaftless screw conveyor and tube screw conveyor. Customers can select the type based on the material to be transported, for instance cement, biomass, sludge, lime, grain, fly ash, and other small particle, dry and viscous material. The material in screw conveyor is transferred and conveyed by the rotating spiral vane. The weight of the material generates the force that doesn't let it rotate along with the conveyor blade. There are spiral blades welded on the conveyor's rotating shaft. The blade's surface type depends upon the material to be conveyed.