apparatus and a method for its use in cleaning comminuted thermoplastic material for reuse in manufacture of molded plastic products . batches of plastic including adherent label materials and adhesives are agitated by a rotor until frictionally heated to a predetermined temperature . a flow of air is used to carry away loosened labels and adhesives . a small amount of water is introduced as a spray to dissolve adhesives and soften remaining label materials further , while loosened pieces continue to be removed in a stream of air . thereafter , remaining adherent particles are removed in an aspirator providing a multi - stage cascade through counter - currents of air , and the particle - carrying air is then cleaned in a cyclone separator .