Abstract: An apparatus for batch coating liquid onto core pieces of particulate matter said apparatus having a processing mode and a discharge mode, and comprising a rotatable drum having a substantially right cylindrical shape, a horizontally disposed longitudinal axis, an interior surface, an exterior surface, a loading end and a discharge end, a loading opening at said loading end and a discharge opening at said discharge end, and farther having a frame for supporting said drum, drive means for rotating said drum about its longitudinal axis in a processing direction and oppositely in a discharge direction, at least one nozzle for introducing a spray pattern of liquid or gas into the drum, and a plurality of vanes affixed to the interior surface of said drum, said vanes configured to move the core pieces toward the loading end of said drum during processing and to produce a continuous cascade of core pieces over said vanes and into the spray pattern.