The present invention relates to a separator for separating air and possibly present solids from a mixture of dental waste water, comprising an air-water separator, wherein a mixture supply tube opens into a centrifuge drum, an air discharge duct extends from the centrifuge drum to the mixture supply tube and the centrifuge drum includes an upper drain edge over which a water outlet is guided onto the outside of the centrifuge drum. In accordance with the invention, the separator is characterized in that the mixture supply tube opens onto a central turbine wheel arranged above the centrifuge drum bottom and an impeller of a waste water delivery pump, which communicates with the water outlet, is arranged on an outside of the centrifuge drum in the vicinity of the centrifuge drum bottom.