A separator for separating liquid droplets from an aerosol is provided, including a rotor arranged in a housing and including a plurality of parallel disks, a dirty gas inlet, a clean gas outlet, and an annular space between the rotor's circumference and the housing, wherein adjacent disks form an interspace therebetween, the radially outer area of the interspace opening into the annular space, and wherein one of the dirty gas inlet and the clean gas outlet communicates with the annular space and the other communicates with radially inner areas of the interspaces. The disks have flat disk bodies perpendicular to the rotor axis, and between adjacent disk bodies, there are a plurality of adjacent channels allowing passage of the gas to be cleaned. Each channel is curved and the radially outer channel wall forms an impaction and separation surface for the liquid droplets.