Abstract: There is disclosed a heated aeration method of completing the processing of a partially treated mixture of wastewater sludge and alkaline materials to produce a biologically active but pathogenetically clean fertilizer which can safely and easily be spread on agricultural lands. Also disclosed are a product made by the method and an apparatus for carrying out the method. The mixture is loaded into a forceful stream of heated air which carries the mixture through a rotating, internally vaned drum which has an internal, longitudinal, vaned core which rotates with the drum. The core and the vanes impart paths to the mixture particles which allow smaller particles to exit quicker than larger and thereby avoid sterilization and which breaks up larger mixture particles and otherwise enhances the spreadability of the resultant fertilizer. A vane on the core is bent and its portion beyond the bend is pronged to facilitate showering rather than dumping mixture particles.