Evaluation of mine tailings’ potential as supplementary cementitious materials based on chemical, mineralogical and physical characteristics

• Published in: Waste management (Elmsford) Vol. 102; pp. 710 - 721
• Main Authors: Simonsen, Anne Mette T., Solismaa, Soili, Hansen, Henrik K., Jensen, Pernille E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01-02-2020
• Subjects: Characterization study; Construction Materials; Environmental Pollution; Mine tailings; Partial cement replacement; Silicon Dioxide; Supplementary cementitious materials; Mine tailings; Supplementary cementitious materials; Characterization study; Partial cement replacement
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2019.11.037

•5 out of 13 mine tailings can possess chemical contribution as SCM.•3 out of 13 mine tailings can possess physical contribution as SCM.•Mine tailings possess significantly different characteristics than CFA and cement.•Chemical and physical pretreatment can potentially optimize mine tailings usage.
In order to reduce emissions of CO2 from cement production and avoid severe environmental pollution from the deposition of mine waste, this study investigated the possibility of utilizing mine tailings as supplementary cementitious materials (SCM) for partially replacement of cement in concrete. This study provides a characterization study of mine tailings to evaluate their potential for contributing chemically or physically as SCM. 13 mine tailing samples were characterized in regards to chemical composition (XRF, Loss on Ignition, CaCO3 and pH), mineralogical content (XRD) and physical characteristics (Grain size distribution, Specific Surface Area, SEM-analysis). The characterization study showed five mine tailings to possess potential chemical contribution as SCM based on their chemical composition (SiO2, Al2O3, Fe2O3 and CaO) and amorphous content. Three mine tailings showed potential physical contribution as SCM based on grain size and grain morphology. The remainder mine tailing characteristics suggest that their potential as SCM may be improved by pretreatment such as milling and/or thermal treatment.