(US4927528-A)      Appts. for sieving out usable compost from rotted organic waste, comprises feed funnel having vertical wall opposite sloping wall, and delivering waste onto conveyor belt supplying the interior of an open-ended rotary sieve drum aligned with the conveyor. Beneath the drum is another conveyor collecting usable material falling thorugh the drum, from the other end of which reject material is discharged. Pref. light material such as plastic pieces, plastic bags, are blown or sucked from the sieve drum.    Pref. the appts. is on a wheeled chassis.    (14pp)    (DE3777360-G)      When organic waste from forestry operations, graveyard rubbish etc. has been allowed to rot in lines of dumps, valuable compost soil is sorted from inorganic material (plastic, tins) by a wheeled trailerwith four belt conveyors and a revolving screen drum. The last belt conveyor discharges the compost soil in a dump alongside the trailer. The trailer receives power from the hydraulic system of a tractor to which it is coupled by the coupling. A first belt conveyor takes the waste from the funnel in the revolving screen drum which is keptclean by a revolving wire brush. The screen underflow is taken by a second conveyor to a third (cross) conveyor which discharges the compost earth by an ascending fourth conveyor in a dump alongside the trailer.    ADVANTAGE -   This causes less environmental pollution than burning the rubbish and creates valuable compost soil.    (DE3644146-C2)      Sieve arrangement for sieving compost earth made of rotten organic material, includes a filling funnel for applying the materials to an advancing band, a sieve drum open at both ends, whose axis runs parallel to the band direction and a drive unit.    The latter rotates the drum about its axis, and the material is transported from one side to the other during rotation. A second advancing band is located under the sieve drum and removes earth which falls through the sieve.    ADVANTAGE -   The arrangement is efficient and enables non-rolled components to be sepd. out.