Abstract: A plant for the biological treatment of solid organic waste, where the organic mass is fed into a treatment tank with a horizontal bottom, while screw propellers, suspended from a sliding bridge parallel to tank base, operate immersed in the matter and whose axis is inclined according to a convenient angle, preferably between 5° and 50°, compared to its vertical, moving the organic matter from the bottom upwards and from the inflowing side of the treatment tank to the outflowing one, continuously immersed in a direction which is at right angles compared to the direction of movement of the organic mass and remaining continuously active, that is without any idle return of the screw propellers across the treatment tank after each process cycle.

Abstract: An air classifier for separating light reusable materials from a stream of non-shredded solid waste is provided. The air classifier employs two operating phases. The first operating phase, the desired light fraction is entrained in an air stream and is conveyed above the remainder of the solid waste. The waste material is then received by a second conveyor so that the lighter fraction is received on top of the heavier fraction. Thus, the first phase of the apparatus effects mass stratification. During the second operating phase, the light fraction is actually removed from the heavy fraction by a high velocity air stream which is preferably induced by a reducing cross-section portion of the apparatus. The air flow through the apparatus is captured and recycled and the light fraction being separated therefrom in, for example, a cyclone.

Abstract: A processing apparatus for solid waste including a rotor with a plurality of blades mounted thereon for shredding solid waste in corporation with a number of counterblades. A prescreening system is provided adjacent the inlet to the shredding elements so as to allow small abrasive items to be removed from the waste prior to shredding. A flexible cleaning system is provided for cleaning waste wrapped about the rotor between the blades. Further, a system is provided for preventing nonshreddable materials from jamming the rotor blade/counterblade system and for diverting such nonshreddable materials to a designated hopper.