The interrelationship between Bond and Hardgrove grindabilities

Abstract

The Bond grindability has the advantage that it can be empirically related to the energy required for comminution (work index), whereas the Hardgrove test has the advantage of being easier to perform. In an effort to establish a valid correlation between work index and Hardgrove grindability, a series of parallel grindability tests were carried out on a wide variety of rocks and minerals. The standard Hardgrove test was modified to allow for materials with a higher density than coal. A new satisfactory relationship was established which permits rapid estimation of work index from Hardgrove test data.