When tunnel boring machines (TBMs) excavate intact high-strength rock masses, creating kerfs on the tunnel face is a promising solution to enhance the efficiency of TBM cutters. The cutters can be arranged to cut between kerfs or cut along kerfs. The rock breaking mechanism of cutting along kerfs is not fully revealed yet, and a quantified comparison in cutting performance between the two arrangements

The fatigue characteristics of rock materials significantly impact the economy and safety of underground structures during construction. Hence, it is essential to conduct further investigation into the progressive damage processes of rocks under cyclic loading conditions. This research utilised both laboratory experiments and discrete element simulations to investigate how confining pressure and fatigue

In greenstones of the east-central Yilgarn Craton, Western Australia, Li-Cs-Ta (LCT) pegmatites of the albite-spodumene type (resources > 300 Mt at 1.4% Li2O) are spatially associated with high-T (650–450 °C) granite-pegmatite-related skarn and skarn-quartz vein Au-Ag deposits (production 580 t Au). U-Pb and Rb-Sr ages (2.65–2.62 Ga) link both the LCT pegmatites and gold deposits to a suite of peraluminous

Rock-breaking is a fundamental process in subsea tunnel construction, particularly during deep trench excavation. Understanding the failure process and permeability evolution of rock masses under hydro-mechanical coupling is essential for optimizing excavation plans and ensuring construction safety. Due to the challenges of capturing crack propagation and permeability evolution solely through experiments

Natural gas hydrate (NGH) is a potential alternative source of energy for the future, and the low mining efficiency severely restricts its commercial utilization. Recently, the cavitation jet technology has been emerging as a prospective way of drilling rate improvement for the industrial development of NGH. The breaking and mining efficiency of cavitation jet is strongly associated with the nozzle

Fracture permeability is influenced by the mechanical properties of geomaterials, surface geometry, aperture distribution, and stress conditions. However, accurately characterizing fracture surfaces and aperture distributions, along with their effects on permeability under stress remains challenging. This study systematically investigates the evolution of fracture permeability and closure behavior

In this paper, physics-informed neural network models are developed to predict the concentrate gold grade in froth flotation cells. Accurate prediction of concentrate grades is important for the automatic control and optimization of mineral processing. Both first-principles and data-driven machine learning methods have been used to model the flotation process. The complexity of models based on first-principles

Hard-rock lithium exploration faces challenges due to less advanced deposit and exploration models compared to commodities like copper. Additional obstacles arise from the glaciated and densely vegetated terrains typical of much of Europe, which present additional obstacles to access and geological mapping. Our research focuses on a belt of LCT (Li-Cs-Ta-rich) spodumene pegmatites on the eastern margin

One of the possibilities for mitigating global climate change is to replace the burning of hydrocarbons with cleaner wind and solar energies, but the problem is storing the energy efficiently. To solve this problem, one of the most promising alternatives is the use of rechargeable and efficient lithium batteries. The importance of this work is that a green method to extract lithium from clays (the

This study focuses on a new optical measurement technique for understanding the flow structure in an opaque suspension. Such opaque systems occur frequently within flotation cells. Adding fluorescent dye to the liquid phase of the suspension enhances the visibility of the particles significantly, at a solid concentration of 10% by mass. The image contrast is sufficient to derive the velocity field

The bioleaching of chalcopyrite is limited by its slow leaching rate. To improve dissolution kinetics, the effects of Fe2+ and Fe3+ on mechanical activation-pretreatment chalcopyrite leaching by Acidithiobacillus caldus (A. caldus) and Sulfobacillus thermosulfidooxidans (S. thermosulfidooxidans) were studied. Mechanical activation reduces particle size and causes lattice defects in chalcopyrite, leading

The demand for high-purity vanadium is projected to rise significantly in the coming decades, driven by its critical role in various industries, such as energy storage, steel manufacturing, and catalysts. Ensuring the purity of vanadium from hydrometallurgical processes is crucial to maintaining the high quality required for these applications. This review examines the most recent advancements in purification

The S2O82−/Fe2+ system can be used to depress PbS, where the activation of S2O82− leads to the generation of SO4•− radicals that oxidize PbS. However, a high S2O82−/Fe2+ dosage is needed for PbS depression (0.15 mol/L). In this study, ultrasonication was employed to improve the depression ability of S2O82−/Fe2+. The flotation and contact angle results implied that 120-kHz ultrasonication enhanced the

Precise prediction of crack opening displacement (COD) is necessary to control it within a certain threshold to ensure safety of critical buried rock structures (e.g. geological disposal facilities), and rock COD nowadays tends to be estimated using distributed fiber optic sensing (DFOS) data. The frequently used methods for computing COD of engineering structures from DFOS data are based on analytical

A series of laboratory experiments were conducted on Hawkesbury sandstone specimens that were exposed to a simulated fire following the modified hydrocarbon fire curve (MHC). For comparison, a similar test program was performed on specimens heated at four rates (2 °C/min, 5 °C/min, 10 °C/min, and 20 °C/min) up to 1100 °C and untreated specimens. Both uniaxial compressive strength (UCS) and elastic

Aluminum is typically produced by processing bauxite through the Bayer process to yield alumina, which is then subjected to electrolysis via the Hall process. This conventional method encounters several challenges, including the scarcity of high-grade ore resources, the inability to process low-grade ores, the generation of red mud as solid waste, difficulties in recovering associated scattered metals

The upgrading of Apa (Apatite) from Dol (Dolomite) by flotation is an extremely challenging job because of their resembling surface characteristics and the inferior selectivity of conventional fatty acid. In this work, an eco-friendly polymer surfactant dextran sulfate sodium (DSS) was evaluated as a novel Dol inhibitor to separate Dol and Apa and the selective depression mechanism was unveiled from

The selective separation of antimonite and arsenopyrite minerals is both a critical and challenging task. This study investigated the combined inhibitory effects of two new reagents on the flotation behaviour of these minerals under low-alkalinity conditions. The inhibitory effects and adsorption mechanisms of these reagents were systematically studied through microflotation and mixed ore flotation

Though octyl hydroxamic acid (OHA) has been extensively employed as the collector for monazite flotation, the weak collecting ability that OHA exhibits calls for improvement. In this article, the researchers systematically investigated the beneficial effects and mechanism of Pb2+ for flotation process of monazite. We commenced with micro-flotation tests, which indicated that the presence of Pb2+ could

Sedimentary basin-hosted manganese oxides may represent an important yet underexplored source of critical metals. Here we present a stratigraphic, textural, mineralogical, and compositional characterization of Mn-oxide nodules, coatings, and veins in the Pisco onshore forearc basin, Peru. The Mn-oxide mineralization is stratabound within marine sandstone, siltstone, and tuff from the Neogene Chilcatay

Underground mining catastrophes mainly stem from the gradual weakening of coal and its adjacent rock formations, induced by complex stress variations occurring during loading and unloading processes. Although several cyclic loading and unloading tests have been conducted on rocks to evaluate this concern, there is a dearth of understanding of the distinct damage mechanisms that occur in coal and rocks

This paper presents the role of microtexture and mesotexture in the separation performance of an ore. Microtexture analysis highlighted the influence of mineral grain size distribution in mineral liberation and separation recovery. Mesotexture analysis highlighted the contribution of vein structures in mineral liberation and provided insights of the origin of liberated particles observed during microtexture

Mineral flotation corresponds to a separation process accompanied by fluid flow, where bubbles are taken as a carrier dropping particles to the fluid surface. Considering that the particle motion is strongly affected by flow conditions, the microscopic interaction behavior between the bubbles and particles should be changed accordingly. In this study, CFD numerical simulation is initially conducted

The composition of quartz has historically been considered unimportant for mineral exploration, although this perspective is changing with the advancement of analytical techniques. The ability to measure trace element variations in quartz provides a unique window into the evolution of mineral deposits. Granites are currently of interest as they can host late-stage magmatic-hydrothermal mineralisation

The discretization algorithm for the root mean square of the first derivative (RMSFD) significantly affects the effective characterization of rock joint profile roughness and the accurate evaluation of the joint roughness coefficient (JRC). The classic discretization algorithm Z2 fails to distinguish morphology roughness differences in isomeric profiles, limiting its characterization capability. To

This study researched into the underlying influence mechanism of Ca2+ and Mg2+ on the rheological properties of kaolinite slurry through rheological technique, turbidity analysis and DLVO theory calculation. The rheological results showed that both the viscosity and yield stress of kaolinite slurry were reduced under high Ca2+/Mg2+ concentration. The apparent viscosity of slurry containing Mg2+ was

Activated carbons (ACs) prepared from agricultural residues are ideal alternatives to the commercial coal-based ACs often applied in gold mining. Carbon activation using KOH produces high-quality carbons with good textural properties. Herein, fruit peel ACs were synthesized via KOH activation and evaluated for aurocyanide adsorption. The yield and adsorption capacity were optimized through a central

Optical microimages of minerals obtained by optical microscopy are cheaper than backscatter images obtained by scanning electron microscopy. With the rapid development of artificial intelligence technology, the intelligent recognition and segmentation of minerals in optical microscopic images based on deep learning has become a current research hotspot. However, there are little research on the segmentation

Model-based controllers often extend improved performance to mineral processing plants by leveraging predictive models to account for system dynamics, handling constraints, adapting to changing conditions, and optimizing control inputs. Inaccurate models will cause a deterioration of controller performance, which is often the case for grinding mill circuits. The plant model ratio was developed to diagnose

This study presents the first investigation into the application of a combined depressant, Gellan gum (GG)/tannic acid (TA), for the selective flotation separation of pyrochlore and barite, using CaCl2 as an activator and NaOl as a collector. Micro-flotation experiments demonstrated that GG/TA at a 1:1 ratio effectively depressed pyrochlore flotation while maintaining high barite recovery, achieving

The application of intensified flotation cells, also known as reactor-separator cells, has become widespread. The tailings recirculation back to a feed conditioning tank is a unique characteristic of these cells compared to mechanical cells and columns. This short communication evaluates, by simulation, the impact of the volume of this conditioning tank on the overall (exhaustion) kinetic response

Understanding the propagation behavior of cement grout in rough-walled fractures is crucial for predicting its effectiveness and design of optimal grouting schemes. To investigate radial propagation of cement grout in saturated rough-walled fractures, a water-cement grout two-phase flow model in rough-walled rock fractures is developed using the phase field method, Herschel-Bulkley model, and mass

This preliminary research was aimed at identifying a suitable area for producing efflorescent sulfate salts enriched in elements of interest. An old retention impoundment of heap-leaching liquors situated in the municipal district of Nerva, southwest of Minas de Riotinto (Iberian Pyrite Belt, Huelva, Spain), was chosen for the study. The study zone has a higher part composed of leached mine spoils

Hydrogen-based mineral phase transformation (HMPT) has been proven to be an effective method for treating Bayan Obo polymetallic ore, where the grinding operation, as a critical step, directly impacts the efficiency of the entire process. In this study, grinding tests were conducted using a vertical stirred mill with pre-enrichment concentrate from Bayan Obo. The effect of HMPT on the grinding kinetic

The bond-based peridynamics shows significant potential in describing and simulating the continuous-discontinuous problems like rock mass. However, the theory developed so far with account of the bond stretch and shear mechanisms exhibits unreasonable prediction of bond force and the appearance of negative shear stiffness when Poisson’s ratio exceeds a critical value. In this work, the root cause behind

The Katanga Copperbelt stands out as one of the world’s largest sediment-hosted Cu-Co provinces, contributing to over 68% of global Co and 15% of global Cu production. The age of these sedimentary Cu-Co deposits remains contentious. This paper presents the first Lu-Hf dates for apatite samples from the late diagenetic to syn-orogentic mineralization phase at Luiswishi, yielding ages of ca. 475–470 Ma

The intrinsic anisotropy of shales, arising from their complex microstructure, including mineral alignment and bedding orientation, significantly influences seismic wave propagation, impacting subsurface imaging and reservoir characterization. Despite extensive research on shale anisotropy, studies employing cubic specimens under true-triaxial conditions, which provide a more realistic simulation of

Chalcopyrite and galena, as common sulfide minerals, are often associated in nature. Because of their similar floatability, it is difficult to separate them under natural conditions. In this study, N,N-dimethyldithiocarbamate sodium (N,N−DDS) was selected as a depressant for separation of copper-lead sulfide minerals. The micro-flotation test showed that under low alkalinity conditions (pH 8), with

Natural spherical graphite (NSG) is one of the indispensable raw materials for the fabrication of lithium-ion battery (LIB) anodes. The advancement of LIB materials has led to a growing need for the production of ultrapure NSG materials. In this paper, we developed a novel hot-pressure acid leaching method, which could improve the purification efficiency while significantly reducing the hydrofluoric

In mineral processing, partition curves are used to describe the probability of a particle of a given size or density reporting to the overflow or the underflow stream. One simple descriptor is the Rosin-Rammler (Weibull) functional form, based on a sharpness parameter, α. An alternative descriptor was introduced by Scott and Napier-Munn (1992) based on the simplified Whiten equation expressed in terms

The rapid growth of spent lithium-ion batteries urgently demands environmentally friendly recycling solutions. Flotation technology not only achieves the separation of cathode and anode materials but also creates favorable conditions for their subsequent recycling and reuse. This study reviews the current global recycling policies and the principles of flotation separation of cathode and anode materials

The flip-flow screen was an important method for classifying fine minerals. The impact load had a significant impact on the dynamic characteristics and screening performance of the flip-flow screen-plate. In its traditional screening theory model, the influence of mineral particle-groups as impact loads was often overlooked. Consequently, this study developed a deflection calculation model for the

Grinding is a critical operation in mineral processing, with ball mills serving as essential equipment in these processes. This study presents an optimization method for accurate ball loading in ball mills based on grinding kinetics principles. The optimal media ball sizes for different particle size ranges were determined as Φ60 mm for −3 + 2 mm, Φ50 mm for −2 + 1 mm, Φ30 mm for −1 + 0.5 mm, and Φ30

High gradient magnetic separation coupling with magnetic fluid (HGMSCMF) was proved to be effective in eliminating competing capture and enhancing selectivity, but several HGMSCMF stages were still required for processing refractory weakly magnetic minerals. Separation performance of high gradient magnetic separation is determined by the selective capture of valuable minerals, but the capture behaviors

Backfill has become an essential element of underground mining operations around the globe. However, a significant amount of fine-grained tailings can affect the consolidation performance and reduce the strength of backfill. It has been reported that mixing active materials with tailings, while calcining at high temperatures can enhance the gelling activity and strengthen the backfill. To examine the

The Nong Sua Sn deposit in Thailand is a typical vein-type deposit with three generations of tourmaline (Tur I, II and III). Tur I as disseminations (Tur Ia) or nodules (Tur Ib) in the pegmatite-aplite stock crystallized from the late-magmatic stage. Tur II coexists with quartz in a complex vein system within the stock and is of magmatic-hydrothermal origin. Tur III occurs in cassiterite-tourmaline

With the expansion of underground engineering into deeper levels, the frequency of rockburst disasters has gradually increased, posing serious threats to the safety of construction personnel and equipment. The occurrence of rockbursts typically involves information about time, location, and intensity, which makes it challenging for traditional single‒intelligence prediction methods to capture the multiple

China had a large number of high-grade iron concentrate powder available for utilization, and the process of smelting them using blast furnaces resulted in substantial emissions of CO2. Compared to carbon reduction, hydrogen reduction could greatly reduce the emission of greenhouse gases and harmful gases. To efficiently convert high-purity iron concentrate into metallic iron, the process and mechanism

Even though most past endeavors concluded no significant mechanical weakening of chalk flooded by supercritical CO2, here, we comprehensively assess the mechanical response of a depleted chalk reservoir by considering the most pessimistic experimental results reported in literature in terms of mechanical alteration of chalk by supercritical CO2. The primary aim stems from the lack of simulation studies

The foaming performance of flotation agents significantly limits the flotation recovery of minerals, particularly in extreme environment like low temperatures. Currently, many methods such as adding emulsifiers to improve the foaming performance, in addition to increasing the cost of reagents, other reagents will be introduced into the flotation system, affecting the recycling effect. In this study

The hydration characteristic of quartz surface is the key of quartz deep flotation purification. In this study, molecular dynamics (MD) simulation and experimental methods were used to study the effect of lattice Fe3+ impurities on quartz surface hydration properties. Quartz samples with different lattice Fe3+ content were obtained by roasting H2SO4-HCl-HF mixed acid with NH4Cl. The changes in the

The southeastern Tibetan Plateau formed by the oblique indentation of India into Eurasia. The concurrent formation of major ore deposits provides an opportunity to test how structural reactivation and block rotation may have controlled mineralisation. A systematic structural analysis and low-temperature thermochronological data have been combined to establish the structural evolution and controls on

Conventional flotation cells are widely used for concentrating iron ores, yet one major challenge remains – the low recovery rate of ultrafine particles, particularly when processing low-grade deposits. This study explores the application of anionic polyacrylamide (APAM) in hematite and quartz mixtures (D50: 1 μm, feed grade: 27.2 % hematite) to selectively aggregate hematite for enhanced flotation

The vigorous development of the steel industry has led to a significant increase in the accumulation of steel slag, causing serious environmental pollution. Consequently, there is a pressing need to explore additional methods for effectively treating steel slag. The Ca, Fe and other valuable elements in steel slag that can be recovered to produce high value-added products by analyzing the chemical

Nickel laterite ore is a crucial raw resource for the development of new energy and materials sectors. In this study, an environment-friendly and economical process for saprolitic laterite was proposed using nitric acid pressure leaching technology. Firstly, the dissolution of lizardite and magnetite, oxidation of Fe2+, and hydrolysis of Fe3+ were evaluated via the thermodynamic analysis. Subsequently

The grain size effect of rocks is crucial for engineering applications, including mining, tunneling, and oil extraction. Previous studies on the effect of grain size revealed discrepancies between experimental results and numerical simulations, hindering accurate predictions of rock strength and deformation. Initially, a parallel bond model was applied to describe the grain boundary contacts and investigate

The unpredictable development of random cracks in reinforced concrete linings under high internal water pressures poses significant challenges for the operational safety and management of hydraulic tunnels, particularly in water-permeable linings used in pumped storage power stations. To address this issue, this study introduces an innovative structural design: a reinforced concrete water-permeable

This paper presents the industrial application of a new comminution circuit of high pressure grinding rolls + one-stage grinding + two-stages continuous classification in a tungsten beneficiation plant. The effects of the modified process on the technical indicators of the grinding circuit were evaluated under normal production conditions in the plant. The results show that the modified process meets

High-purity quartz sand is an important raw material in the high-end silicon industry and is globally recognised as a key strategic resource. Currently, the problems of high energy consumption, long cycle time, low yield, and serious environmental pollution caused by by-products of the production process remain to be solved. In this study, a reverse-flotation anionic/cationic combined collector coupled