Abstract: A first thermally insulated hollow cylinder is mounted for rotation about its longitudinal axis and a second hollow cylinder is mounted within the first cylinder for conjoint rotation therewith. The ends of the cylinders are closed to define a first annular chamber therebetween and a second chamber within the second cylinder. Inlet means for waste is provided communicating with the annular chamber adjacent one axial end thereof and a portion of said second cylinder adjacent the other axial end of said annular chamber is formed as a sieve permitting transfer of material from said annular chamber to the second chamber. Discharge means are provided communicating with the chamber within said second cylinder at the same axial end as the inlet, for the discharge of composted material.

Abstract: Grinding mill including at least one container partially filled with grinding media, and at least one excitation member extending in direction of the longitudinal axis of the container and disposed within the container so as to be surrounded by the grinding media received in the container; the excitation member being supported on the wall of the container by a plurality of individual rod-shaped support elements extending substantially radially from the excitation member and disposed in spaced relationship to one another in direction of the longitudinal axis.