Proposal of New Construction Material: Polymer-Stabilized Gold Ore Tailings Composite

Abstract

Recent events involving the rupture of tailings dams in Brazil have motivated the search for alternatives to incorporate the material into the production chain. At the same time, the consumption of raw materials by the civil construction sector is high, requiring the incorporation of alternative materials to achieve sustainable development. Thus, this paper proposes a new construction material based on the mechanical and microstructural behavior of polymer-stabilized and fiber-reinforced gold ore tailings composites. Unconfined Compressive Strength tests were performed on different polymer contents (6% and 9%), dry unit weights (1.7 g/cm³ and 1.8 g/cm³), and curing periods (7 and 28 days), according to 2K Experimental Design. Microstructural tests were performed using X-ray Diffraction, X-ray Fluorescence Spectrometry, Optical Microscopy, Scanning Electron Microscopy, and X-ray Micro-Computed Tomography. The results demonstrate that adding polymer increased tailings’ mechanical behaviors by forming packages with the lamellar particle, which was observed in microstructural tests. The polymeric composites’ brittle behavior was improved using fiber insertion, leading to an increase of the strain energy absorption capacity. The polymer-stabilized and fiber-reinforced gold ore tailings composites demonstrated its potential as a construction material, especially in landfill structures, tailings stockpiles, and paving base layers. The association of mechanical and microstructural analysis established a new understanding of the effect of the stabilizer and the reinforcement.

The Application of an Eco-Friendly Synthetic Polymer as a Sandy Soil Stabilizer

“…CHN Elemental Analysis showed that the polymer comprises 69.03% carbon, 7.01% hydrogen, and 0.52% nitrogen. The product is frequently used for pavement sealing and as a soil stabilizer [ 2 , 3 , 6 ].…”

“…When considering the use of polymers in soil stabilization, they can be categorized into three major groups: geopolymers, biopolymers, and synthetic polymers [ 5 ]. Geopolymers are inorganic substances of aluminosilicate with combinations of other elements [ 4 , 6 , 7 ]. Biopolymers are produced based on bacteria biomass and are common in nature [ 8 , 9 , 10 ].…”

Key Success Factors for the Practical Application of New Geomaterials

“…However, microstructural analysis is required for a comprehensive understanding of the behavior of composites in tailings. Since tailings materials have not undergone the typical soil formation process, classical soil mechanics may not accurately represent their behavior [34][35][36][37].…”

Utilization of Palm Oil Fuel Ash (POFA) as an Admixture for the Synthesis of a Gold Mine Tailings-Based Geopolymer Composite

“…One approach gaining a lot of attention recently is the circular economy, a concept integrating systems engineering, waste reprocessing, waste stabilization and waste repurposing to recirculate as many materials, wastes and by-products as possible back into circulation. Industrial wastes, including mine tailings [10], sludges [11], mine by-products such as clays [12] and mine waste rocks [13], have been repurposed as fillers for civil construction [14] and inert backfills [15,16] as well as reprocessed to extract base metals such as Cu [17], Au [18] and critical minerals [19]. The direct repurposing of mine tailings and industrial wastes as filler materials for construction is, however, problematic because of the possible release of heavy metals into the environment [20,21].…”