Maximizing Centrifuge Dewatering Performance While Minimizing Power Consumption and CO2 Emissions

Decanter centrifuges provide excellent biosolids dewatering performance. The trade-off is that they typically consume more power than other dewatering technologies. Alfa Laval has focused on the continuous improvement of centrifuge design to maximize dewatering performance minimizing power consumption and the associated CO2 emissions. Alfa Laval's Second Generation (G2) design launched in 2004 reduced power consumption by 1) decoupling the main drive motor and backdrive motor, which eliminated the need to brake the conveyor, 2) incorporating a variable conveyor pitch which reduced cake friction and 3) utilizing grease lubricated main bearings which reduced bowl friction. The G2 design also incorporated a steep cone that improved dewatering performance without sacrificing power consumption. The Third Generation (G3) design launched in 2011 further reduced power consumption by recovering wasted energy from the centrate discharge and by reducing the internal centrate discharge radius. This paper focuses on the dewatering performance improvements and power reduction features of the G3 design.