Abstract: Apparatus and methods for separating a fluid, with the apparatus including a rotatable drum having an inner drum wall and an outer drum wall disposed around the inner drum wall to define a separation passage therebetween. The apparatus also includes radial separator blades that are curved in a circumferential direction and are disposed in the separation passage of the drum, the radial separator blades extending radially at least partially between the inner drum wall and the outer drum wall. The apparatus further includes a first circumferential separator blade that is curved in a radial direction and is disposed in the separation passage of the drum, the first circumferential separator blade extending at least partially around the inner drum wall. The apparatus also includes a housing disposed around the drum and configured to receive a higher-density component of the fluid separated in the separation passage.