GB476772A - Process of and apparatus for making fertilisers, soil improving agents or other hygienically unobjectionable substances from organic matter, particularly waste material - Google Patents

Abstract

476,772. Manures. PETERSEN, K. Aug. 24, 1936, No. 23269. Convention date, Aug. 26, 1935. [Class 111] [Also in Group XII] In making manures &c. by subjecting waste materials of vegetable or animal origin to an aerobic biological conversion in a horizontally disposed rotating solid-walled container through which oxygen-containing gases are passed, the process is so conducted that the materials remain in the form of a homogeneous aqueous pulp throughout the conversion and the contact between the oxygen-containing gases and the pulp is increased by raising portions of the pulp above the level of the bulk of the pulp into the flow of the gases and/or by passing such gases through the bulk of the pulp below the level thereof. Garbage, offal, night-soil, sewage sludge, fµces, or industrial or horticultural refuse or mixtures thereof mav be so treated. The conversion may be assisted by the presence of culture-carrying bodies such as stone-chippings, pieces of slag, wood, cork or the like, such bodies alternately contacting with the gas and the liquid phases. A portion of the end product may be returned to the container.. The end product may be concentrated by sedimentation, centrifuging or drying. Suitable apparatus comprises a rotating drum to which the comminuted or sorted material is charged by means of a hopper. As shown in Fig. 2, the drum may comprise a hollow central core 7, the space between the core and the circumferential wall being divided longitudinally by means of grids 8 into a plurality of compartments, and each compartment being partially filled with small stone-chippings, pieces of slag, wood, cork or the like. Air flows through the drum and the converted material is removed as a pulp through a stationary shoot associated with a circular outlet opening covered by a strainer or the like. According to another modification, Fig. 3, a system of spaced perforated tubes 9 is arranged along and adjacent the inner circumferential wall of the drum. These tubes communicate with a hollow cylindrical core 11 through radial pipes 10, the core receiving a stationary air supply conduit 11a having a downwardly facing longitudinal slot 11b whereby the air supply to the perforated pipes not submerged in the pulp is automatically cut off. The container may also be provided with rigidly secured or loose lamina or with wires or pipes perpendicular to or parallel with the axis of rotation of the container. According to another modification, the inner circumferential wall of the rotating drum is provided with a plurality of radial lifters or scoops which during rotation lift suitable disintegrating bodies found in the drum to a certain level and then let them fall so as to comminute the material in the drum. The drum may be rotated, and a fan for supplying air to the drum may be operated, by means of a wind rotor.