Improvements in solid Bowl centrifuges and Unloading Spiral

摘要

A solid bowl decanter centrifuge comprising a solid, generally cylindrical bowl having a liquids outlet at one end and a solids outlet at the other end, and adapted to be rotated at a first speed. Inlet pipework enables influent to be introduced to the interior of the bowl. A scroll conveyor is mounted for rotation within the bowl at a second speed. A first motor has its output shaft coupled to the scroll conveyor whereby the motor speed determines the differential speed of the conveyor relative to the bowl. A control mechanism is adapted to measure the torque applied to the scroll conveyor and to control the speed of the scroll conveyor in dependence upon the measured torque, a second pump being adapted to pump flocculant into said inlet pipework at a rate dependent upon the torque controlled differential speed of the scroll conveyor.