Decanter centrifuge with adjustable gate control

摘要

A decanter centrifuge comprises a bowl and a worm or screw type conveyor. The bowl is rotatable about a longitudinal axis and has a cake discharge opening at one end and a liquid phase discharge opening. The conveyor includes a conveyor hub having at least a portion disposed inside the bowl for rotation about the longitudinal axis at an angular speed different from an angular rotational speed of the bowl. The conveyor further includes a helical screw or worm attached to the conveyor hub and disposed inside the bowl for scrolling a cake layer along an inner surface of the bowl towards the cake discharge opening. An adjustable component on the hub forms a gap between the hub and the inner surface of the bowl so that the gap has a size adjustable independently of hub rotation speed. The adjustable gap enables an optimization of the moisture content of cake exiting the bowl at the cake discharge opening for a given solids throughput and cake rheology. The adjustable component on the hub takes the form of an annular weir or a baffle plate.