Agitator mill for wet comminution, with separator to retain grinding beads

摘要

Stirred grinding mill with continuous flow between inlet(4) and outlet (21) includes a rotating shaft carrying agitators (3). The mill vessel (1) is charged with grinding beads, which are retained by a rotary separator located on the shaft, in advance of the outlet. The separator has radial openings which extend from an annular, internal region about the shaft, through to an outer, annular space forming part of the main grinding volume. In this novel design, the rotary (6) separator is designed to classify by centrifugal force. The radial openings are formed by gaps between adjacent rotor blades (10). The finest particles achieve the outlet by axial travel, but coarse material is flung outwards to return to the mill. Also claimed is a grinding circuit, in which the mill described, has a centrifuge (or similar) at the outlet, to return any oversize to the lower input of the mill, and deliver the fines as product.