Process mineralogy of high-silicon iron tailings from Hebei province by MLA

Mineral liberation analyser (MLA) was applied to quantitatively analyze the High-Silicon iron tailings from Hebei Province. Mineralogy parameters, such as chemical composition, mineral composition, element occurrence state, mineral grain size distribution, mineral assemblage, and liberation degree. Results show that the iron grade in the iron tailings is 9.18%, and the silicon grade is 44.22%. Iron is primarily hosted in gangue minerals such as olivine (45.65%) and chlorite (20.19%), with lesser amounts present in metallic minerals like magnetite (12.11%). Silicon is predominantly hosted in quartz (59.90%), followed by silicate minerals such as plagioclase feldspar (19.46%). The iron-bearing mineral in the iron tailings is magnetite, with a content of 1.23%. The primary gangue minerals include quartz, sodium feldspar, potassium feldspar, olivine, and chlorite, among which quartz has the highest content at 41.23%. Iron tailings have a broad particle size distribution and poorly liberated minerals. The mineral intergrowth relationships are complex, featuring close intergrowths between different minerals. Magnetite often occurs as a gap-filling material between intergrown grains of quartz and silicate minerals, making it difficult to both liberate and recover. Quartz is a recyclable gangue mineral that often occurs closely intergrown with silicate minerals such as feldspar and olivine, forming irregular polygonal interlocking structures. Both its liberation and recovery are challenging. To recover quartz, tailings must undergo thorough liberation, while also addressing iron removal and the separation of quartz from silicate minerals like albite and potassium feldspar. The research findings provide fundamental theoretical data for the comprehensive recovery and utilization of iron tailings.