Abstract: A rotary vacuum filter apparatus has a filter drum with a rotating hollow through axle carrying radial pans arranged to scoop up filtrate in the bottom of the drum and raise the filtrate to a level for draining into the axle through holes so arranged as to prevent drainage of filtrate back into the drum. A pump draws air from the drum through the axle at high velocity providing an air lift sweeping the filtrate out of the axle for discharge from the filter unit. Two diametrically opposed pans spanning substantially the entire length of the drum can radiate from opposite sides of the axle or a plurality of diametrically opposed pairs of pans can be mounted along the length of the axle and radiate therefrom in circumferentially offset positions to provide a more continuous scooping action in the bottom of the drum and the axle can be drained from one or both ends.