Morrell Method for Determining Comminution Circuit Specific Energy and Assessing Energy Utilization Efficiency of Existing Circuits

This guideline condenses the works of the Morrell method for predicting the specific energy consumption of conventional crushing, High Pressure Grinding Rolls (HGPRs) and tumbling mill equipment and applies them to assessing operating comminution circuit performance. Such circuits include combinations of any of the following equipment: Autogenous Grinding (AG) and Semi-Autogenous Grinding (SAG) mills, ball mills, rod mills, crushers, and HPGRs. The guideline reviews the data required for the analysis, including hardness characterization data generated from the SMC Test® and Bond Ball Mill Test Work Index, presents the Morrell equations and their applications, and provides a worked example. Although the Morrell method can be used in comminution circuit design in greenfield projects, this document provides guidelines to use the method to assess the energy utilization efficiency of existing circuits. 

This guideline was developed by the Industrial Comminution Efficiency Working Group, now a sub-committee of the Mineral Processing Working Group.