Method and apparatus for reducing and classifying mineral crystalline and brittle noncrystalline material

Abstract

A rapid reduction apparatus and method includes a reduction and classification apparatus (20) having a reducing unit (22) composed of a contraction cone (28) for receiving the material to be processed. The contraction cone (28) is connected to an expansion cone (32) through an intermediate venturi section (30). Air is drawn through the venturi section and the expansion cone (32) by a turbine (34) mounted below the expansion cone. A standing shock wave (310) is established in the expansion cone, and material loaded into the expansion cone is disintegrated and reduced as a result of attrition grinding within the shock wave and upon contact with the blades of the turbine. The reduced material is then discharged into the classifier assembly (50) where the particles and air flow undergo a series of vertical motion reversals defined by a plurality of baffles (112-128) extending alternately from the top and bottom of the classifier assembly (50). Each reverse in the air flow is accompanied with flow friction losses, thereby reducing wind velocity and applied particle pressure resulting in the discharge of particles of equivalent size and weight into corresponding hoppers (86-96) spaced along the flow path and substantially below each baffle extending from the top of the classifier assembly.

Dependencies are inferred from the claim text.