A method for centrifugally separating whole blood into red blood cells and
a plasma constituent rotates about a rotational axis a separation zone
having radially spaced apart walls with a high-G side and a low-G side
located closer to the rotational axis than the high-G side. Whole blood
enters the rotating separation zone in an entry region to begin
separation. Separation is halted by a terminal wall that is
circumferentially spaced from the entry region. The whole blood separates
into red blood cells toward the high-G side and plasma constituent toward
the low-G side. The method directs red blood cells separated in the
separation zone in a circumferential flow direction toward the terminal
wall. The method directs separated red blood cells from the rotating
separation zone through a second path that extends, at least in part,
radially beyond the high-G wall.