A centrifugal separator for separating gas and liquid from a gas-liquid mixture, the centrifugal separator comprising: a housing having a cavity and a gas-liquid mixture inlet leading tangentially into the cavity along an inlet path to form a vortex therein, a separated gas outlet and a separated liquid outlet; and a rotor rotatably mounted to the housing inside the cavity in a manner to be freely rotatable around a rotation axis, the rotor having a hub extending axially along said axis, the rotor having a plurality of vanes extending radially from the hub inside the cavity, the vanes being disposed in the inlet path in a manner so that the rotor is rotated by the gas-liquid mixture during use.