The increasing demand for sustainable construction materials has driven significant interest in utilizing recycled concrete aggregates (RCA). However, the mechanical performance and durability of RCA are often compromised due to the presence of residual mortar. This study explores an innovative surface treatment approach combining abrasion and cement slurry coating to improve the properties of RCA

Multistage fractures in different reservoirs exhibit competitive extension and mutual feeding mechanisms under different fracturing sequence conditions. To better understand these mechanisms for a more efficient extraction of mine gases, a combination of true triaxial physical tests and numerical simulation was performed in this study. The expansion process of hydraulic fractures in different layers

The Bushveld Complex in South Africa contains the largest reserves of platinum group elements (PGEs) in the world. It is composed of the Merensky reef, UG2 reef and the Platreef. Unlike the other reefs that have been largely exploited, the Platreef ores have proved to be difficult to process due to their low content of PGE sulphides and the low association of the PGM minerals with the base metal sulphides

In this study, dynamic photomechanical blasting experiments were conducted to investigate the interaction mechanisms of dual cracks induced by explosions at different relative positions. The experimental results demonstrate that both cracks penetrate when the actual relative vertical distance at which the crack tips begin to interact is within 10 mm in the experimental group; however, when it exceeds

Hydrophobic modification of sulfur-containing waste rock is a promising strategy for reducing acid mine drainage (AMD) generation. This study investigated the use of sodium oleate and nano silca to modify sulfur-containing waste rock and evaluated the acid-suppressive properties of the sodium oleate and nano silca treatment through static and dynamic leaching tests. Results from these tests indicated

In this century, our daily life is surrounded by technological devices, and Rare Earth Elements (REE) are at the heart of this technological revolution. They are always listed having the highest supply risk in critical minerals published by different countries. From that point of view, their extraction, and creating a secured supply chain is always crucial. In this research, the influence of calcination

High gradient magnetic separation (HGMS) is a potential method of separating chalcopyrite from copper-arsenopyrite co-flotation concentrate. However, during the co-flotation process the addition of bleaching powder (ClO−), which has been a common depressant for arsenopyrite, deteriorates their separation selectivity in the subsequent HGMS process, and until today this effect of ClO− is unknown to people

Flotation is a potential method for extracting residual copper sulfide (CuS) from the acid-leaching residue of copper smelting dust; however, the inhibitory impact of Bi(III) in the flotation pulp significantly hampers its practical application. In this study, we systematically investigated the inhibition mechanism of Bi(III) on CuS flotation and propose a method to prevent inhibition. Microflotation

A prototype finite element double porous Thermo-Hydro-Mechanical (THM) model that considers elastoplastic and damage evolution effects, is used to investigate deformability, fluid flow and heat transfer during injection of carbon dioxide (CO2) injection. The primary objective is to explore the feasibility of injecting CO2 at temperatures lower than the surrounding formation, including subzero conditions

X-ray radiography presents a non-invasive and dynamic approach for examining multiphase flows, particularly in complex systems like flotation froths. While this technique has been applied successfully in various multiphase studies, such as granular flows and fluidised beds, its utilisation in understanding flotation froths is novel. This study aimed to investigate the behaviour of particles and bubbles

Fluid extraction from sandstone oil, gas, or geothermal reservoirs causes elastic and inelastic compaction of the reservoir, which may lead to surface subsidence and induced seismicity, as observed in the Groningen Gas Field, Netherlands. The inelastic compaction is partly caused by rate- or time-dependent processes, meaning that compaction may continue even if production is stopped. To reliably evaluate

The Brazilian dolomitic itabirites are considered marginal resources and deposited in waste rock dumps as the cationic reverse flotation circuits present limitations to remove carbonate minerals. This work proposes the synthesis and application of N,N-bis(2-hydroxyethyl)oleamide as a collector in the flotation of carbonates present in dolomitic itabirites. Hematite, quartz, calcite, and dolomite samples

The geometric shape of the slope and the distribution characteristics of the complex fracture system significantly impact the stability of highly-jointed rock slopes. Constructing an accurate three-dimensional (3D) geological model is crucial for the 3D stability analysis of these slopes. However, the numerous minor discontinuities in rock slopes complicate model construction and reduce computational

Ash content is a key indicator to evaluate coal flotation concentrate quality and adjust flotation process parameters, which could be determined by analyzing froth images. In this research, a multi-scale multi-task neural network (MSTNet) was developed to realize accurate determination of the ash content of industrial coal flotation concentrate by analyzing froth images. Furthermore, transfer learning

It is of great significance to improve the flotation of copper sulfide minerals at low temperatures. In this study, the reduction mechanism of chalcopyrite flotation performance and the role of copper ions in improving the flotation of chalcopyrite at low temperatures were systematically investigated. The results of the flotation tests prove that the chalcopyrite flotation recovery is lower at low

This study presents the development and validation of a digital twin for a semi-autogenous grinding (SAG) mill controlled by an expert system. The digital twin integrates three key components of the closed-loop operation: (1) fuzzy logic for expert control, (2) a state-space model for regulatory control, and (3) a recurrent neural network to simulate the SAG mill process. The digital twin is combined

In 2020, the European Union officially designated strontium as a Critical Raw Material (CRM) due to its diverse applications and limited global producers, with Spain as one of the primary producers and the only one in the EU. This comprehensive review discusses strontium market dynamics, global reserves, and technological advancements in mineral processing techniques to extract and concentrate its

Fluidized bed flotation involves three phases of gas, liquid and solid, which can be used for the separation of coarse minerals. In this study, a two-dimensional gas–liquid-solid fluidized bed was developed to explore the fluidization characteristics of fluidized bed flotation. The effects of water velocity, air velocity, frother dosage and particle size (Ql, Qg, ρn, Dp) on the average pressure drop

Quartz and feldspar are the primary impurities in the mineral processing of pollucite. Due to the highly similar surface properties of these three minerals in terms of physicochemical characteristics, achieving efficient flotation enrichment of pollucite has been a challenging problem. To address this issue, the development of flotation collectors with high selectivity towards pollucite is crucial

Environmental factors and water scarcity have led to the recirculation of greater quantities of water in mineral processing plants. Recycling water or using alternate water sources, e.g. seawater, for flotation can result in an increase in ionic concentrations and lower water quality. Water recirculation and lower water quality can increase ionic strength which can cause corrosion, scale formation

Fluorite and barite share similar physicochemical properties, making them challenging to separate efficiently using flotation. To address this problem, sodium oleate (NaOL) was used as a collector to study the separation effect of carboxylated chitosan (CCS) as a depressant for fluorite and barite. Infrared Spectroscopy (FTIR) test, X-ray photoelectron spectroscopy (XPS), Zeta potential test, contact

The supply of the strategic metal titanium is of great significance in ensuring the sustainable development of the national economy and national defense. As an irreplaceable raw material in the titanium industry, ilmenite has become increasingly prominent in its commercial demand and strategic position. With high-quality ilmenite resources continuing to be developed, these resources are typically characterized

Gold recovery from wastewater should be cost-effective, efficient, and environmentally friendly. In this study, adsorbents containing Fe(II,III) systems were prepared via thermal modification of pyrite. The effects of thermal modification temperature, the source of pyrite, pH, ionic strength, adsorbent solid–liquid ratio, and coexisting metal ions on adsorption were investigated. Further, the removability

This study aims to optimize the adsorption process of gallic acid (GA) on Cu-Al layered double hydroxides (LDHs) synthesized via a co-precipitation method at various pH levels. The procedure is based on the adsorption of organic pollutants from aqueous solutions, with evaluations carried out based on operational parameters such as pH, initial concentration, and adsorbent quantity. Two series of LDHs

Coal and other mineral resources are also commonly found in bauxite mining. The process of bauxite mining is usually affected by retained ore pillars in other strata, which leads to the formation of combinations composed of different strata. Once these combinations become unstable, they can cause serious disasters that threaten production safety. Aiming at the safe mining of co-associated resources

Underground infrastructures are crucial for resource extraction, energy storage, and space utilisation. The geomaterials that make up these structures, such as rock and concrete, are subjected to multiaxial stress conditions and are frequently exposed to dynamic and extreme loadings caused by both natural disasters and human activities. These stresses are particularly significant during the construction

Microwave fracturing has great potential in improving the efficiency of hard rock breaking. However, the pore evolution, which can be regarded as the damage accumulation and progressive failure of the rock subjected to microwave irradiation, remains unclear. In this study, nuclear magnetic resonance (NMR) is employed to investigate the pore evolution and fracture mechanism of the sandstone under different

This study focused on the preparation, characterization and photocatalytic performance of a monolithic composite made from vanadium-titanium magnetite tailings and quartz sand. Rhodamine B was used as a pollutant model and the photocatalytic degradation of rhodamine B by the prepared composites was investigated. The results indicated that the composite could effectively degraded Rhodamine B, achieving

The leaching liquor extracted from ion-adsorption type rare earth (RE) ores contains large amounts of aluminum (Al) ions. The neutralization-precipitation method for Al removal results in the loss of large amounts of RE, leading to the waste of RE resources. Preliminary research has shown that the introduction of acetic acid (HAc) during the Al removal process could effectively reduce RE loss. However

Rock fragmentation is a critical process for mineral extraction and for mitigating overstressed rock in geotechnical applications. In this study, 3D-printed concrete was used to simulate the stratified rock mass, and experimental and numerical methods were employed to investigate crack propagation under static expansive loadings in transversely isotropic rocks. Two types of cracks were observed in

This study performed mechanical tests and monitored acoustic emissions (AE) in shale samples with six bedding layer orientations (β = 0°, 30°, 60°, 90°, 120°, and 150°) to investigate the progressive damage mechanisms under direct shear. The results revealed that the peak shear load (Pcr), crack initiation threshold (Pci), crack damage threshold (Pcd), and cumulative AE count exhibited an approximate

Stress-induced brittle fracturing near an excavation boundary results in a volume increase, known as bulking. Excessive bulking places added demand on the rock support, which, if not detected and addressed through preventative support maintenance (i.e., proactively added reinforcement), can cause the support to fail, leading to a safety hazard and costly production delays for underground mining operations

The liquid alkali decomposition method represents a relatively clean smelting process for the treatment of the mixed rare earth concentrate derived from Bayan Obo. However, the production process generates a considerable quantity of alkaline wastewater, which presents a significant obstacle to the large-scale application of this process. Accordingly, the reduction and high-value treatment of rare earth

The surface composition, coordination environment, and chemical state of arsenopyrite dictate the propensity of the mineral to undergo oxidation, leaching, and flotation separation. Because of this, it is of great significance to study the mechanism by which mechanical ball milling affects the composition and coordination of the surface atoms. In this study, the arsenopyrite powder was ground using

This work attempts to clarify the reason for low gold recovery in Carlin-type gold ores flotation by revealing the correlation of interactions between pyrite and dolomite during the oxidation process with flotation performance. In this paper, the sulfur oxidation rate determined by Ion chromatography (IC) was adopted to evaluate the oxidation degrees of the mixed pyrite and dolomite systems. Flotation

Precious metals (PMs), particularly platinum group metals (PGMs), are of strategic importance due to their high supply–demand imbalance, scarcity, and functionality in high-tech fields. The global supply of PMs is constrained due to the rising demand in clean energy applications. Therefore, the recycling of PMs from secondary resources can effectively alleviate the risk of supply shortages. Pyrometallurgical

Underground hydrogen energy storage (UHES) in lined rock caverns (LRCs) represents a crucial solution to the challenge of unstable and uneven clean energy generation. Nevertheless, the attainment of enhanced storage efficiencies frequently necessitates the utilization of elevated hydrogen storage pressures. Consequently, a comprehensive understanding of the elastic-plastic mechanical response of surrounding

Fluid injection via a vertical well into a high-temperature formation may induce multiple longitudinal thermal fractures, which may eventually transition to two-wing fractures during fracture propagation, depending on horizontal stress ratio κ. In this study, we develop a plane strain model with radial heat conduction to investigate either two-wing fractures under highly anisotropic stresses κha≫1

Cycle flotation tests have been preferred for obtaining metallurgical projections based on laboratory flotation tests because they can simulate a continuous circuit similar to real flotation plants. However, cycle tests are typically conducted in the laboratory under a limited number of operating conditions, so the behavior of ores in these tests might only partially represent the complexity and variations

Understanding fault dynamics is essential for comprehending the underlying mechanisms of seismic events. This study introduces a novel fault activation-shearing-sliding model within a peridynamic (PD) framework, characterized by distinctly defined static and kinetic frictional behaviors. Static friction bonds are developed to sustain normal forces perpendicular to the fault plane and to manage tangential

Understanding fracture slip susceptibility in geothermal reservoirs is central to the control of fluid injection-induced seismicity. To investigate the role of regional fracture systems on induced seismicity, a coupled thermo-hydro-mechanical (THM) model containing fracture networks was developed, which features direct coupling between different physics for explicit fractures, fractured rocks (porous

In-situ stress is essential in shale reservoir fracturing, driving oil and gas migration and informing wellbore stability and drilling optimization. The accurate prediction of 3D in-situ stress is inseparable from seismic data. However, existing methods predominantly rely on empirical formulas or simplified assumptions, which limit their accuracy in representing the real distribution of in-situ stress

Chemical and mechanical processes are coupled in many geological and geochemical environments. Reactive processes anneal defects and restructure grain boundaries, modifying their elastic properties, levels of internal friction, wave propagation rates and fracture behaviors. The nature of these changes is, however, contingent on the initial state of the rock. In this study, impulse excitation was used

The increase in CO2 emission during Portland cement manufacturing has motivated studies on new binder systems. The production of alternative cements with less environmental impact (zero clinker) has been gaining increasing interest, mainly because green cements emit smaller amounts of CO2. One of these binders, the geopolymers, are obtained from the alkaline activation of materials rich in silica and

In China’s rapid development, the metallurgy industry plays a pivotal role. However, the processing and utilization of iron ore results in the production of a significant amount of iron-bearing smelting slags. Iron-bearing smelting slags contains iron, zinc, copper, calcium, potassium, and other metal elements. Challenges in processing technology and cost control in smelting enterprises contribute

Direct aqueous mineral carbonation of olivine minerals has been extensively investigated in the past. However, the effect of inorganic electrolytes, particularly sodium sulfate (Na2SO4), on mineral carbonation rate has not been investigated yet. In this work, we report experimental results on the CO2 uptake rate of ultrafine olivine-rich rocks using Na2SO4 and sodium chloride (NaCl) as inorganic catalysts

A non-invasive technique named positron emission particle tracking (PEPT) is used to study the dynamics of mineral particles found in froth flotation. High frequency tracking is required to fully resolve turbulent flow paths with highly fluctuating velocity components. Tracking frequency is also called “location rate”, which is the number of tracked locations per second. A time interpolation algorithm

Multiwell fracturing is a key technology for developing shale gas and shale oil reservoirs. In this study, a multiple planar 3D (PL3D) fracture simulator that can capture multiple thin layers was developed to examine the propagation of multiple fractures during multicluster fracturing in multiple horizontal wells. The simulator considers multiple thin layers in the vertical direction. The results of

Impregnated diamond bits (IDBs) are widely used for drilling in hard formations. To improve the drilling efficiency and exposure behavior of IDBs in granite, three types of Cu-based basalt fiber (BF) composite IDBs were designed and prepared by using the medium-frequency induction hot-pressing and sintering method, in which 0 wt% BF and 25 vol% diamond were used in 0BF25D IDB, 1 wt% BF and 25 vol%

This research develops an energy-driven constitutive model designed to tackle the complex phenomenon of grain crushing in porous rocks. Initially, a novel coupled relationship is proposed to integrate various energy dissipation mechanisms, including both plastic and crushing effects, using spherical polar coordinates. This approach results in a robust coupling of energy dissipation, providing a comprehensive

The stress-strain state of the saturated porous media determines the behavior of fracturing, which defines the efficiency of developing tight oil, shale, coalbed, and thermal energy fields. Therefore, reliable hydromechanical coupled simulations with destruction reconstruction are critical.

Accurate determination of the representative elementary volume (REV) size plays a pivotal role in analysing the mechanical properties and failure processes of heterogeneous rocks in complex engineering environments. In this study, a novel microstructure modelling strategy (NMMS) for determining the REV size is proposed by combining deep learning and an improved phase-field method (PFM). Micro- and

The green processing of weakly magnetic iron ore is inseparable from high-intensity and high-gradient magnetic separator (HGMS), which is one of the most energy-intensive magnetic separation equipment. Iron (Fe) armor serves as the key primary structure for enhancing magnetic field conduction efficiency within the magnetic system. The order of magnetic properties of commonly used magnetic yoke materials

This paper investigates an observable dynamic model of froth flotation circuits aimed at online state and parameter estimation and model-based control. The aim is to estimate the model states and parameters online from industrial data. However, in light of limitations in the plant data, additional model analysis is conducted. It is shown that without online compositional measurements, only the states

A laboratory-controlled milling process of silica sand was carried out using aluminum oxide balls of three different sizes. The ball wear kinetic equations were experimentally obtained from the evolution curves of the ball diameter as a function of the operating time. From a generalized model, the ball entrance flux and ball wear consumption were calculated using exact two-parameter solution functions