NOVELTY - Biologically oxidizing organic matter while in the state of finely powdered waste, comprises oxidation of organic matter in reaction vessel (1), which is supplied with oxidizing air. The waste is supplied into top end of upright reaction vessel, that in reaction vessel is effected stirring and/or migration of spheres (7), which fill up the vessel and on surfaces of which the matter to be oxidized is present in thin layers.    USE - For biologically oxidizing organic matter while in the state of finely powdered waste (claimed).    ADVANTAGE - The method is capable of maximizing the oxidation performance of a biological oxidation process, i.e. the oxygen supply of microbes, so as to speed up the entire oxidation process, to oxidize all of the organic matter, and to provide an increase in production capacity more economically than in the prior art.    DETAILED DESCRIPTION - Biologically oxidizing organic matter while in the state of finely powdered waste, comprises oxidation of organic matter in a reaction vessel, which is supplied with oxidizing air regulated in terms of heat and humidity and from which is discharged a hot moist gas, and for enhanced oxidation. The organic matter is provided with a recyclable oxidizing surface. The waste is supplied into the top end of the upright reaction vessel, that in the reaction vessel is effected stirring and/or migration of spheres, which essentially fill up the reaction vessel and on the surfaces of which the matter to be oxidized is present in thin layers, that oxidizing air is blown into the reaction vessel below the reaction vessel's oxidizing zone and, if necessary, into and/or above the oxidizing zone. The discharge of air from the bottom end of the reaction vessel is precluded and air is discharged from the top end of the reaction vessel by the application of suction, exhaust air is cleaned, heat is transferred from the exhaust air to the air being blown into the reaction vessel, and oxidized matter is discharged from the bottom end of the reaction vessel.    An INDEPENDENT CLAIM is also included for an apparatus for oxidizing organic matter while in the state of finely powdered waste, comprising a reaction vessel, devices for supplying the reaction vessel with matter to be oxidized, devices for supplying the reaction vessel with oxidizing air regulated in terms of heat and humidity, devices for drawing a hot moist exhaust gas from the reaction vessel, devices for scrubbing the exhaust gas, and a heat recovery unit (16) for the transmission of heat from the exhaust gas to the inlet air. The reaction vessel comprises an upright vessel higher than its diameter, the top end of which is provided with distributing elements (9) for matter to be oxidized for dispersing the matter to be oxidized across the reaction vessel in its top end, that the oxidizing surface is constituted by biologically unoxidizable spheres, which essentially fill up the reaction vessel and on the surface of which the matter to be oxidized deposits in a thin layer. The apparatus further comprises elements (5) for stirring and/or migrating the spheres in the reaction vessel, elements (6) for conveying the spheres from the bottom end to the top end of the reaction vessel, elements (12, 29) for blowing oxidizing air into the reaction vessel below its oxidizing zone and, if necessary, into and/or above the oxidizing zone, shut-off elements (23,32,33) for precluding the discharge of oxidizing air from anywhere else except from the top end of the reaction vessel, elements (13, 15) for exhausting hot humid air from the top end of the reaction vessel, and elements for cleaning the exhaust air.    DESCRIPTION OF DRAWING(S) - The figure shows a view of a thermal insulated reaction vessel.    Reaction vessel (1)    Elements for stirring and/or migrating the spheres (5)    Elements for conveying the spheres (6)    Spheres (7)    Distributing elements (9)    Elements for blowing oxidizing air (12, 29)    Elements for exhausting hot humid air (13, 15)    Ionic cleaners (14)    Heat recovery unit (16)    Scraper (19, 22)    Floor (20)    Receiving space (21)    Shut-off elements (23,32,33)    Gap (24)    Discharge conveyor (25)    Singlet oxygen generators (27)    Screen (31)