Study on Solidification and Stabilization of Antimony-Containing Tailings with Metallurgical Slag-Based Binders

Abstract

Blast furnace slag (BFS), steel slag (SS), and flue gas desulfurized gypsum (FGDG) were used to prepare metallurgical slag-based binder (MSB), which was afterwards mixed with high-antimony-containing mine tailings to form green mining fill samples (MBTs) for Sb solidification/stabilization (S/S). Results showed that all MBT samples met the requirement for mining backfills. In particular, the unconfined compressive strength of MBTs increased with the curing time, exceeding that of ordinary Portland cement (OPC). Moreover, MBTs exhibited the better antimony solidifying properties, and their immobilization efficiency could reach 99%, as compared to that of OPC. KSb(OH)6 was used to prepare pure MSB paste for solidifying mechanism analysis. Characteristics of metallurgical slag-based binder (MSB) solidified/stabilized antimony (Sb) were investigated via X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). According to the results, the main hydration products of MSB were C-S-H gel and ettringite. Among them, C-S-H gel had an obvious adsorption and physical sealing effect on Sb, and the incorporation of Sb would reduce the degree of C-S-H gel polymerization. Besides, ettringite was found to exert little impact on the solidification and stabilization of Sb. However, due to the complex composition of MSB, it was hard to conclude whether Sb entered the ettringite lattice.

Present Situation and Research Progress of Comprehensive Utilization of Antimony Tailings and Smelting Slag

“…In addition to the preparation of building materials, some scholars have proposed to use a variety of solid wastes to prepare cementing materials as the cementing agent for antimony tailings and prepare underground filling materials for the disposal of antimony tailings. Li et al [32] used high-content antimony tailings, blast furnace slag, steel slag, and flue gas desulfurization gypsum to prepare green mine filling materials. According to the test results, its compressive strength is greater than 1 Mpa, which meets the needs of mine filling.…”

The Failure Mechanical Properties of Cemented Paste Backfill with Recycled Rubber

“…Uniaxial compressive strength (UCS) is a commonly used mechanical index, which directly reflects the hardening process of CPB [45][46][47][48]. In a UCS test, the CPB can generate, propagate, locate, and accumulate cracks, resulting in a series of stress-strain behaviors [49][50][51]. The strength and deformation behavior are the criteria used to measure the fracture evolution or failure of CPB, and thus, they have been the main focus of CPB research to date.…”

Research on Dewatering Characteristics of Waste Slurry from Pipe Jacking Construction

“…Untimely reduction leads to no place to store excess waste slurry, resulting in the stagnation of construction. Solidification technology is often used to increase the strength of soft soil [ 20 , 21 , 22 , 23 ] and has been applied in some projects [ 24 ]. The curing agent converts the excess free water into mineral water through hydration, which improves the mechanical properties of soft soil.…”