A centrifugal separator and a method for separation of particles from a gas stream is disclosed. The separator includes a frame, a gas inlet and a gas outlet. A centrifugal rotor is arranged to be rotatable in the frame around a rotational axis and includes a plurality of separation plates defining separation passages between the plates. A central gas chamber in the rotor communicates with a radially inner portion of the separation passages and the gas outlet. A space surrounding the rotor communicates with a radially outer portion of the separation passages and the gas inlet. A device is configured to bring the gas stream in rotation upstream of the rotor. The centrifugal rotor is configured such that the rotational flow of the gas mixture drives the rotation of the centrifugal rotor for separating particles from the same gas stream being conducted from the space surrounding the rotor, through the separation passages between the plates and towards the central gas chamber.