Process and apparatus for continuous treatment of dusty, powdery and granular materials

Claim 1

A process for continuous treatment of dusty, powdery and granular particulate materials, said treatment being for drying, cooling or chemical reaction between the gas and solid phase, by means of the sensible heat of a gas serving simultaneously as the temperature conditioning medium and as the carrier, comprising: introducing a gas stream at the inlet for said material which bears the wet material to be treated tangentially into a circular path in which the particles move in a revolving ring which lies in the plane of said inlet; drawing off the gas stream axially from said revolving ring at the outlet, which lies in a plane below said outlet, said stream undergoing a plurality of revolutions in said circular path before it is drawn off in the outlet location which is below the inlet, while the incoming stream continues the circular movement; said circular movement in the treating chamber forming a vortex sink below the inlet and adjacent the outlet, the new wet particles flowing into the process displacing the dried particles which, after progressive treatment are drawn into weak radial flow into the center of the vortex sink and are thereafter removed; the newly introduced wet particles and the partially dry particles moving in circular paths having different radii with a dead spot created in the vortex by shaping the center with a closed tube and the sides by the outward slope of the bottom of the container and by the extension of the walls of the container; the concentration of wet and partially dry particles moving in the circular paths being greater than the concentration of particles in the incoming stream fed into the inlet and in the outgoing stream which exits from the outlet; and removing the particles at the outlet by virtue of suction created thereat.