A review of the applications of the JK size-dependent breakage model Part 2: Assessment of material strength and energy requirement in size reduction

It has been 10 years since the JK size-dependent breakage model was developed (Shi and Kojovic, 2007). Part 2 of the review focuses on the model application to the assessment of material strength and energy requirements for size reduction. In the application for assessment of ore pre-weakening effects, two methods, the A×b based method and the t10 based method, are reviewed. The review also covers a coke strength index, the JKCSI, which unifies various rotating drum indices in different world standards into one single index, and a procedure to predict coal grindability, the HGI. In the application for energy assessment, the JK size-dependent breakage model is used to smooth the energy-size reduction relationship and predict crusher energy requirement, to explain the non-linear response of power station grinding mill capacity with the coal grindability index HGI, to develop a benchmark energy factor to assess energy efficiency for comminution equipment and circuits, and to estimate specific energy reduction resulting from the high voltage pulse pre-weakening effect. Many of these applications were possible only after the JK size-dependent breakage model became available.