DISPERSING PROCESS AND STIRRED BALL MILL FOR CARRYING OUT THIS PROCESS

摘要

A process and apparatus for dispersing solids in a liquid phase are disclosed. A mill base comprising solids and a liquid phase is fed into a hollow body having a substantially cylindrical inner surface and containing a grinding medium and at least one sieve. The mill base is fed radially inwardly into the hollow body toward the sieve, while the grinding medium is rotated relative to the hollow body and the sieve at such a speed that the grinding medium forms an annular charge in contact on an outer side with the cylindrical inner surface of the hollow body and defining on an inner side a cylindrical space essentially free of the grinding medium in which is situated the sieve. The mill base is conveyed radially inward through the cylindrical charge of grinding medium toward the sieve so that a fluidized bed is formed with respect to the grinding medium. The mill base is subsequently conveyed radially inwardly through the cylindrical space which is essentially free of grinding medium to the sieve. The mill base is sifted radially inward through the sieve and is separated from any residual grinding medium. Preferably, the mill base is sifted by means of a cylindrical sieve disposed centrally in the hollow body or by means of a plurality of cylindrical sieves disposed in a circular array about a longitudinally axis of the hollow body. The sieves may be stationary or rotatable with respect to the hollow body.