Textural variants of iron ore from Malmberget: characterization, comminution and mineral liberation

Geometallurgy combines geology and mineral processing into a spatially-based predictive model and is a useful tool that can be used in production management of a mineral processing plant. Two main complementary approaches exist to establish this model. Geometallurgical testing relies on direct measurement of the response of the ore in the processing circuit by conducting several small scale metallurgical tests. The mineralogical approach relies on proper ore characterization and process modeling on mineral basis. Because the latter is generic and applicable to any type of mineral deposit, it was chosen as the main basis of this study and combined with rock mechanics as basic geometallurgical testing.
This work presents comminution characterization of different textural variants of the breccia (semi-massive) iron ore from Malmberget, Northern Sweden. Experimental work includes Point Load Tests, Compressive Tests, comminution as laboratory crushing and grinding, mineralogical characterization and liberation measurements of the products. The results give quantitative information on how physical properties, modal mineralogy and mineral textures are related to comminution and mineral liberation. This work is directly linked with three on-going Ph.D. projects at LTU and contributes to a framework on how mineral textures and liberation information can be included in a geometallurgical model.