Disclosed are systems and methods for a mixing device having a mixing chamber bounded by an inner surface of a wall, the wall having a cylindrical outer face and at least one feed duct which ends on one side with an opening in the cylindrical outer surface of the wall and on the other side with an opening in the inner surface of the wall. The mixing device also includes a magazine having a cylindrical inner surface, the cylinder axis of which is coaxial with a cylinder axis of the cylindrical outer surface of the wall, and a multiplicity of ducts. The magazine and wall are movable with respect to one another such that the openings of the multiplicity of ducts in the inner surface of the magazine are each connectable in a medium-conducting manner to the opening of the at least one feed duct in the outer surface of the wall.