An investigation into the performance of screw feeders used in bulk solid densification processes

The focus of this paper is on the design and performance of specialised screw feeders, which are employed to densify bulk solids as a means of meeting specific process plant requirements. Applications include de-aeration coupled with the achievement of higher packing densities and in other cases, dewatering of wet bulk solids including sludge and compost types of materials. Densifying screw feeders require careful consideration of the bulk density and associated packing ratios of the bulk solids in relation to the major consolidation stresses. The selection of suitable screw feeder geometries to achieve the desired densification along with the nominated feeder throughput requirements is outlined. The methodology for the determination of the screw axial loads, drive torques and power is also presented.