MILLING PROCESS AND APPARATUS

摘要

A mill (10) for grain or other particulate matter is provided with a grinding chamber (12a) which has a stationary grindstone (23) forming a cylindrical wall of the grinding chamber, and rotating fan blades (20) in the chamber to blow grain against the grindstone (23) and around the chamber (12a). By gravitational separation, smaller particles rise upwards in the chamber, while larger, heavier particles sink lower. A plate (19) creates back pressure in the chamber (12a), and allows only a thin stream of fine grain particles to escape from the top of the grinding chamber into a chamber (12b) above. In this chamber, fan blades (21) create a light draft from the edges of the chamber towards the centre, which pulls the finest particles towards a central exit (29), while larger particles are held away from the centre by centrifugal force. Above the central exit (29), a blower (30) blows particles from the exit (29) out an outlet (31) for collection.