Abstract: In a method of continuously composting material capable of being composted by the action of aerobic microorganisms in a reactor, the material is caused to pass through the reactor as a single mass from the top thereof to the bottom thereof from an upper level in said reactor, and in which oxygen-containing gas required for the aerobic decomposition of the compostable material is passed through said single mass in contact therewith. The waste gas from the composting process is removed from the reactor by suction through pipes which extend down into the mass to be composted from the upper level thereof, with the openings of said pipes lying on a level located beneath said upper level in said reactor.

Abstract: The invention is concerned with a method of biologically decomposing organic material by the action of microorganisms thereon in the presence of an oxygen-gas containing medium, in which method the material is charged to the top of a vessel and caused to sink downwardly therethrough while passing one or more zones during continuous decomposition of the material and discharge of the treated material at the bottom of said vessel, the oxygen-gas medium being charged to the bottom of the vessel and caused to move upwardly therethrough against the pressure of the overlying material, wherein the sinking movement of said material is effected by causing one or more rotatable screws to cut and finely-divide the treated material and to transport said cut and treated material to a discharge location in the lower part of the vessel; and wherein the oxygen-gas containing medium is introduced through gas-supply means in the bottom part of the vessel and caused to pass through a layer of particulate material and through a l