NOVELTY - Converting biodegradable waste material (1) into organic fertilizer involves milling the material and optionally desiccating; pulping resultant mixture and mixing with communal sewage sludge; feeding resultant biomass into front part of a temperature-controlled mixing-aerating unit (8); mixing biomass and passing towards rear of aerating unit while producing gases, optionally mixing with air that are continuously re-injecting into bottom region of basin of aerating unit and if desired, powdering/granulating finished organic material reaching rear end of aerating unit.    USE - For converting biodegradable waste material into organic fertilizer which is useful for stopping desertification (claimed) and also in several fields of agriculture.    ADVANTAGE - The process avoids the recycling of the waste materials into production in unaltered form, but impose a longer or shorter storage/repository time; provides the simultaneous, environmentally friendly conversion of fresh and stored organic materials, humus materials, as well as stabilized sewage sludge stored in desiccating ponds or storage ditches into a organic fertilizer reusable in intensive agricultural production; produces the organic fertilizer that is free of added biochemical compounds, and contains very active bacterial flora and humus material, as the remnants of the method, but it is non-infective and the seeds of any weeds are unable to germinate due to the well-defined temperature treatment during the process; and avoids release of the greenhouse gases (e.g. methane) into the environment. The organic fertilizer has a natural soil quality that is restored without the need for using artificial agricultural chemicals (chemical fertilizing agents), since a sterile fertilizer provided which is free of pathogens, parasites and weeds. The appropriately preprocessed biomass entering the mixing-aerating unit has moisture content of 60%, which is necessary to the continuity of the method, since under these conditions the humification of the organic material content takes place, and oxidized forms of the plant nutrients are formed.    DETAILED DESCRIPTION - Process for conversion of biodegradable waste material (1) into organic fertilizer involves milling the biodegradable waste material and optionally desiccating; pulping the resultant mixture and mixing with communal sewage sludge, for providing a biomass with 40-70% dry matter content; feeding the resultant biomass into the front part of a temperature-controlled mixing-aerating unit (8) according to an intermittent schedule; mixing the biomass and passing towards the rear of the mixing-aerating unit, while the gases produced, optionally mixed with air, that are continuously re-injected into the bottom region of the basin of the mixing-aerating unit; and optionally powdering and/or granulating the finished organic material reaching the rear end of the mixing-aerating unit. An INDEPENDENT CLAIM is included for mixing-aerating unit for the treatment of agricultural waste material, comprising at least one elongated basin arranged in a closed, temperature-controllable room, and at least one manipulator movable along the longitudinal axis of the basin(s), where the basin is provided with heating elements in sections and the manipulator has a self-propelling frame, raisable and lowerable mixing unit and an exhausting-injecting unit that are mounted on the frame.    DESCRIPTION OF DRAWING(S) - The figure shows a flowchart of process for conversion of biodegradable waste material into organic fertilizer.    Waste material (1)    Liquid manure (2)    Solid manure (3)    Dehydrator (4)    Storage (5)    Moisture-setting conduit (6)    Pulping machine (7)    Mixing-aerating unit (8)    Telescopic injector (21)    Finisher (22)