Cyclone furnace

Claim 1

A CYCLONE FURNACE FOR BURNING FINE GRAINED FUELS COMPRISING A RADIALLY SYMMETRICAL COMBUSTION CASING INCLUDING END CLOSING PORTIONS, AT LEAST ONE END PORTION COMPRISING A SUBSTANTIALLY RADIAL END WALL PROVIDED WITH A CENTRAL GAS OUTLET, A CIRCULAR PROJECTION CONCENTRIC WITH THE GAS OUTLET EXTENDING INTO THE CASING INTERIOR AND DEFINING SAID OUTLET AND AN ANNULAR SPACE RADIALLY OUTWARDLY OF SAID PROJECTION, SAID ANNULAR SPACE BEING OPEN TO THE REMAINDER OF THE CASING, THE PERIPHERAL WALL OF THE CASING WIHIN THE LENGTH OF SAID PROJECTION BEING PROVIDED WITH A TANGENTIALLY DISPOSED INLET FOR COMBUSTION MEDIUM AND ENTRAINED GRANULAR FUEL PARTICLES, SAID CASING BEING PROVIDED AT THE END THEREOF REMOTE FROM SAID GAS OUTLET WITH A SLAG OUTLET, THE CASING BEING OF SUFFICIENTLY LARGER DIAMETER THAN THE PROJECTION TO AFFORD A SPACE RADIALLY LARGER THAN SAID PROJECTION AND AXIALLY DISPOSED FROM SAID ANNULAR SPACE TO PROVIDE FOR MOVEMENT OF INFED COMBUSTION MEDIUM AND ENTRAINED GRANULAR FUEL PARTICLES IN AN OUTER VORTEX MOVING AXIALLY TOWARD SAID OTHER END PORTION OF THE CASING AND AN INNER VORTEX MOVING AXIALLY TOWARD SAID PROJECTION, THE INNER END OF SAID CIRCULAR PROJECTION BEING SPACED FROM THE OTHER END PORTION OF THE CASING BY A DISTANCE SUBSTANTIALLY GREATER THAN THE AXIAL LENGTH OF THE PROJECTION TO CAUSE THE INNER AND OUTER VORTICES TO BE MUTUALLY ACCESSIBLE THROUGHOUT A SUBSTANTIAL PORTION OF THEIR LENGTHS, SAID SLAG OUTLET EXTENDING TANGENTIALLY FROM SAID CASING IN THE DIRECTION OPPOSITE TO THE DIRECTION OF ROTATION OF THE OUTER VORTEX.