Milling and drying apparatus incorporating a cyclone

摘要

A cyclone (2) which includes an upper cylindrical portion (3) opening into the wider end of a lower frustro- conical portion (4), with a primary air inlet (10) such that the inlet air is substantially tangential to the circumference of the cyclone, and an exhaust outlet (8) at or adjacent the top of the cylindrical portion; a control valve (7) is associated with the exhaust outlet (8) and can be used to partially or completely shut off the outlet (8); a secondary air inlet is associated with the narrow end of the frustro-conical portion (4) and is provided with an air flow stabilising device (13) adapted to admit a stream of air substantially along the longitudinal axis of the cyclone (2); also including means for withdrawing processed product from the frustro-conical portion (4).