A PRP separator-concentrator comprising a housing, a separation assembly, and a concentration assembly. The concentration assembly has a concentration sump. An axially concentric rigid stationary outlet tube is secured to the housing and extends through the separation assembly to the sump. The separation assembly is attached to and positioned above the concentration assembly to form a combined separator-concentrator assemblage that is rotatable about the outlet tube. The separation assembly includes a separation chamber lined with a depth filter having pores and passageways that are sized to receive and entrap erythrocytes during centrifuging. The concentration chamber has a floor for supporting desiccated beads and a wall with at least one opening closed with a screen. The concentrator can have a distribution of upright screen supports, the upright screen supports having an inner surface and an outer surface, the cylindrical screen being supported on the outer surface of the upright screen supports. A stationary bead rake can be secured to the stationary tube and extend outward therefrom, the rake having distal ends that are spaced at a distance from the upright screen supports. The rake can comprise a longitudinal body, the center of which is secured to the rigid outlet tube. The separator-concentrator includes a valve assembly connecting the separation chamber and the concentration chamber. PRP concentrate is produced by contacting PRP with desiccated beads while the beads are stirred with a stationary rake, and rotating the concentration chamber at centrifugal speeds to separate PRP concentrate from the beads.