Abstract: An apparatus and a method for processing municipal waste with increased processing capacity are provided. The apparatus includes at least a cylindrical screen having ridge projections on the inner surface thereof and a group of beaters mounted on a central shaft extending axially through the cylindrical screen. In carrying out the method, the municipal waste charged into the cylinder receives powerful beating and shearing due to the interaction caused by the relative rotation between the tips of the beaters and the ridge projections thereby remarkably increasing the processing capacity.