Patent FR-2976061-B1 (FR)
Inventor: VANDENBUSSCHE FREDERIC
IPC: C04B20/06
Filed: 2011-05-31
Granted: 2013-08-23
Abstract: The device comprises a sealed enclosure (1) that communicates with a generator (20) to generate microwave radiation at a treatment frequency and is provided with a pivot unit for modifying the inclination of the generator with respect to a vertical direction, and a metallic tank. The sealed enclosure has a filling opening with a part located above an axis of the pivot unit. The metallic tank: opens to the microwave generator and to the filling opening to contain the material to be treated used in a cycle; and is rotatable and driven in rotation by a unit for varying its speed. The device comprises a sealed enclosure (1) that communicates with a generator (20) to generate microwave radiation at a treatment frequency and is provided with a pivot unit for modifying the inclination of the generator with respect to a vertical direction, and a metallic tank. The sealed enclosure has a filling opening with a part located above an axis of the pivot unit. The metallic tank: opens to the microwave generator and to the filling opening to contain the material to be treated used in a cycle; is rotatable and driven in rotation by a unit for varying its speed so as to optimize the mixing of the material to be treated by radial ribs integral with the tank; is placed in the enclosure; and further comprises a unit for draining the treated material located in the upper part and used after tilting the enclosure and vessel. An impedance of the tank is adjustable by a unit for adjusting the height of the tank. The inner rotatable tank is made of refractory steel with low resistivity. The enclosure further comprises an outlet adapted to discharge the treated material by gravitation. A seal made of a braided metal: is positioned between the enclosure and its lid so as to prevent the leakage of microwave radiation; and is positioned between the enclosure and a rotating shaft leading to the tank so as to prevent the leakage of microwave radiation. The lid comprises a metal chute system, on its side facing the tank, for draining the treated material. The enclosure, the lid and the tank are thermally insulated using insulating materials such as alumino-silicate fibers with low thermal inertia and are transparent to microwave radiation. The insulating material of the lid is fixed by a fastening system compatible with the microwave radiation. The microwave generator and a waveguide (21) are mounted integral with the enclosure so as to be pivotable. The device further comprises an automatic clamping system that allows unlocking and locking of the wave guide to disconnect and reassemble the waveguide to the enclosure, a quartz window provided at each waveguide flange to prevent dust from rising to the generator, an air injection system disposed on the waveguide to create the overpressure inside the generator and to prevent the spread of dust, a non-conventional microwave heating unit configured to preheat the material to be treated, a unit for recovery heat produced by the treated material, and a unit configured to measure the temperature of the material to be treated to monitor and regulate the heat treatment. The heat recovery unit is present outside of the enclosure. An outlet is disposed on a lower part of the enclosure so as to allow the discharge of dust, debris and particles ejected from the cavity.