an apparatus for comminuting , grinding and dispersing flowable grinding stock has a grinding receptacle with an inner , first grinding surface , which is rotationally symmetrical relative to an axis of rotation , and is drivable to rotate about the axis of rotation . also provided is a grinding roller , which has a second grinding surface that is rotationally symmetrical relative to a central longitudinal axis , and is drivable to rotate about the axis . a grinding gap is defined between the first grinding surface and the second grinding surface .