A centrifugal separator for cleaning of gas from solid or liquid particles suspended therein which are of greater density than the gas, which centrifugal separator comprises - a rotor housing which delimits a separation chamber and has a gas inlet to the separation chamber and a gas outlet from the separation chamber, - a rotor which by means of a driving device is rotatable around a rotational axis and adapted, during operation, to bring the gas into rotation in the separation chamber, wherein the rotor comprises a stack of frustoconical separation discs which are disposed coaxially with one another and concentrically with the rotational axis and which by means of spacing elements (26, 30) are arranged at mutual spacing such that they delimit between them interspaces for gas to flow through, - an inlet space arranged centrally in the stack of separation discs, which inlet space communicates with the gas inlet and with a radially inner part of the interspaces between the separation discs, and - an annular flow space which surrounds the rotor and is delimited radially by the rotor housing, which annular flow space communicates with a radially outer part of the interspaces between the separation discs and with the gas outlet, characterized in that - the interspaces between the separation discs at least at their radially outer part are open for flow of the gas in the circumferential direction and that mutually adjacent separation discs are arranged at mutual spacing such that rotation of the rotor causes in the interspaces a pumping action which drives the gas from the gas inlet, through the interspaces between the separation discs and out via the gas outlet and wherein the separation discs have a plurality of spot-formed spacing elements, which are arranged in said interspaces. - a rotor housing which delimits a separation chamber and has a gas inlet to the separation chamber and a gas outlet from the separation chamber, - a rotor which by means of a driving device is rotatable around a rotational axis and adapted, during operation, to bring the gas into rotation in the separation chamber, wherein the rotor comprises a stack of frustoconical separation discs which are disposed coaxially with one another and concentrically with the rotational axis and which by means of spacing elements (26, 30) are arranged at mutual spacing such that they delimit between them interspaces for gas to flow through, - an inlet space arranged centrally in the stack of separation discs, which inlet space communicates with the gas inlet and with a radially inner part of the interspaces between the separation discs, and - an annular flow space which surrounds the rotor and is delimited radially by the rotor housing, which annular flow space communicates with a radially outer part of the interspaces between the separation discs and with the gas outlet, - the interspaces between the separation discs at least at their radially outer part are open for flow of the gas in the circumferential direction and that mutually adjacent separation discs are arranged at mutual spacing such that rotation of the rotor causes in the interspaces a pumping action which drives the gas from the gas inlet, through the interspaces between the separation discs and out via the gas outlet and wherein the separation discs have a plurality of spot-formed spacing elements, which are arranged in said interspaces.