Grinding energy study using a new laboratory tumbling mill assembly

Abstract

AbstractWith the express aim of developing a new concept, ‘Energy Index’, wherein theoretical energy considerations and practical application will be in agreement, the energy aspects of grinding by a tumbling mill were investigated.For this purpose, a specially designed tumbling mill assembly has been constructed at the University of British Columbia. The assembly consists of three interchangeable cylindrical laboratory-mills of different diameters, together with an automatic speed control system and a torque meter. Experiments were conducted to determine the driving characteristics of tumbling mills and some of the factors affecting comminution energy. It was found that the required torque for grinding remained almost constant throughout the grinding operation, regardless of the material being ground, and the torque for a flat-faced cylindrical mill containing feed material was -about 20 percent less than that containing no feed material. The introduction of a new index – Energy Index – which is a functi...