described herein may be used with the improved system of the present invention and should be selected based upon the character of the waste material which is to be processed since the waste material being processed is generally hazardous it is important that such feeding system make provision to isolate the material from the environment and also exclude oxygen from the system to prevent problems with premature combustion of the material mill 200 as shown in fig1 is a modified dispersion apparatus and includes inlet 202 into mill housing 204 stationary plate 206 is positioned on the interior of housing 204 immediately surrounding the opening of inlet 202 therethrough shear blocks 208 are secured to the inner surface 210 of plate 206 rotating disc 212 is positioned within housing 204 and has shear blocks 214 positioned on its surface 216 facing the shear blocks 208 on plate 206 shear blocks 208 and shear blocks 214 are so positioned to intermesh rotating disc 212 is mounted on drive shaft 218 which is rotated by motor 220 also as with the impellers previously described drive shaft 218 is axially movable to change the spacing between stationary plate 206 and rotating disc 212 so that the macerating action of shear blocks 208 and 214 causes any solids entering.