an apparatus and procedure for efficiently sterilizing waste material or products . the apparatus includes a reactor in the form of a cylindrical container housing two cylindrical tubes , a larger first tube and a smaller second tube . a first helical blade extends inwardly from the inner surface of the second tube , and a second helical blade bridges the outer surface of the second tube to the inner surface of the first tube . as the set of tubes is rotated in unison , material flows in one direction within the second tube and in the opposite direction in the space between the tubes . this axially compact design allows non stop introduction and extraction of waste , efficient use of heat energy , provided by steam injected into the reactor through a steam port , and allows for material to be input into and extracted from the device both at one end of the reactor .