Ball mill

A ball mill for the continuous fine grinding and dispersing of solids in liquid comprising a housing having a central axis and at least one conical inner wall defining a ring shaped chamber radially spaced from said central axis and having a conical cross section, an annular displacement body having a conical cross-sectioned outer surface conforming to said chamber, means for mounting said displacement body within said housing with the conical surface spaced from the conical wall of said ring shaped chamber, to define therebetween an annular gap having in cross-section a pair of angularly disposed connected arms for the passage of solids, liquid and grinding balls, means for rotating said displacement body relative to said housing about the central axis to effect the grinding of said solids by said balls within said gap, an inlet to the radially inner one of the arms of said gap for the introduction of solids and liquid, and an outlet from the radially outer one of the arms of said gap for the discharge of ground solids and liquid, and duct means extending through said displacement body between said outlet and said inlet obliquely to the central axis for return circulation of the grinding balls to said gap.