Compositional properties and geotechnical behavior of mining tailings: a review

What are mining tailings' main chemical, mineralogical, physical, and geotechnical properties, and what potential applications can be assessed based on these properties? To address this question, this literature review focused on these properties as observed in a wide range of tailings. It was identified that these materials are predominantly sandy silts composed of quartz and clay minerals, in addition to specific minerals from the explored ore. Iron and copper tailings most frequently exhibited a sandy texture. The tailings studied show geotechnical characteristics typical of silty soils, with low cohesion and moderate compressibility in most caes. Coal tailings, with high clay and organic matter content, exhibit the smallest friction angle and highest cohesion. Tailings lacking cohesion are predominantly non-clay minerals, especially quartz, with silty-sand particle size distributions, such as copper, gold, and iron tailings. According to their general characteristics, the tailings have the potential to be applied in cementitious matrices, in pozzolanic reactions, or as aggregates, in addition to alkaline activation processes, serving as a source of aluminosilicates or filler materials. Reusing these tailings not only presents an opportunity for waste reduction and contributes to environmental sustainability, but also offers potential economic benefits by providing cost-effective materials for various applications.