A flotation model has been validated against the survey data obtained from a copper rougher flotation circuit with a circulating load. The model was developed using the hydrophobic force as a kinetic parameter, which made it possible to use the contact angles of the free and composite particles as input parameters so that the model can predict both recoveries and grades. The model also recognizes the

We present a novel poro-damage-viscoelastic model for predicting the failure response of fluid-saturated porous geomaterials. The Generalized Maxwell model is introduced for the representation of the viscoelastic behavior of the solid skeleton, which is achieved by a standard Prony-series type expansion. Damage regularization is obtained by an non-local integral-type formulation and damage behavior

Rare earth elements (REEs) can be extracted from monazite under aggressive decomposition and leaching conditions. Much of the waste rocks are removed prior to the extraction process to minimize the costs and waste generation, which is difficult with coal byproducts. The possibility of extracting REEs from low-grade monazite concentrates under relatively mild conditions has been explored to simulate

As the tunnel excavation and resource exploitation go deeper into the Earth, increasing number of rockburst occur all over the world. However, the understanding of rockburst prediction and rockburst proneness evaluation is still at its infancy. In this paper, to accurately and efficiently predict rockburst proneness, a multi-index evaluation method for rockburst proneness of deep underground rock openings

Trainings play a vital role in the transference of knowledge between skilled and novice operators in the mineral industry. Evaluation is an important part of those trainings, but many trainings rely solely on the trainees’ feedback. This paper presents how technology enhancement can help produce more effective training evaluations to the mineral industry. It describes a case study involving a froth

Foamed concrete as energy absorption material for high geo-stress soft rock tunnels has been proven to be feasible due to its high compressibility and lightweight. However, the lengthy curing and defoaming problems caused by the cast-in-place method of large-volume foamed concrete remain unsolved. In this study, we propose a novel energy absorber composed of foamed concrete-filled polyethylene (FC-PE)

This study aimed to investigate the suitability of sodium polyacrylate (PAAS) as a pyrite depressant in a Cu-S separation system through flotation and adsorption experiments. Micro-flotation tests showed that chalcopyrite was selectively separated from pyrite using PAAS as a pyrite depressant in the pH range 2–4. A satisfactory separation effect, a copper concentrate with 30.02% Cu and a recovery of

The aim of the research work was to study the specific process of hydrofluoric acid decomposing (Fe,Mn)(Nb,Ta)2O6 mineral structure. In this paper, X-ray photoelectron spectroscopy (XPS), density functional theory (DFT) calculations combining with leaching experiments were used to study the atoms bonding, charge transfer, and energy changes on the mineral/liquid interface and selective dissolution

The influence of the intermediate principal stress, σ2, is disregarded when rock strength is analyzed using the Mohr-Coulomb or Hoek-Brown criteria. Several polyaxial strength criteria have been proposed to account for the influence of σ2. One of the methods that received considerable attention is the Mogi criterion. The criterion modifies the Nadai or Drucker-Prager approaches by exchanging the normal

In the sulfidization-amine flotation of zinc oxide, the inevitable presence of slime deteriorates the efficiency of zinc recovery, especially in the cleaner flotation stage. However, the relevant deteriorating mechanism has yet to be clearly explained. Results of micro-flotation indicated that the surface oxidization of smithsonite samples could aggravate the adverse effects of quartz slime coating

Two different methods for the modelling of real particle shape in 3D DEM simulations are assessed in this paper. The first method uses overlapping spheres (clumps), while the second uses a block defined as a closed and convex polyhedron. The two methods are applied to the modelling of triaxial tests on a railway ballast. The macroscopic responses obtained with the two methods are compared, and it is

A knowledge of permeability evolution with stress is important for the enhancement of coalbed methane production. In this study, a series of compaction-permeability tests with in-situ nuclear magnetic resonance (NMR) measurement were conducted by using a designed NMR testing system equipped with a loading device. Based on the NMR results, the permeability variation mechanism is investigated during

Most mine sites use large coarse ore stockpiles as a buffer between the mine and the processing plant. Stable operation of the downstream processes demands a uniform output from the stockpile with respect to particle size, however, particle size distributions of the product drawn from stockpiles can vary significantly over time due to various size segregation phenomena. Although quantifying size segregation

As aby-product of waste rock from sulfide ore, Fe3+ is one of the important factors that promote acid production and heavy metals release from waste rock pile fields. In this paper, the dynamic leaching tests were conducted to investigate the behavior of acid generation and heavy metal release from the sulfide waste rock of Dexing copper mine under different Fe3+ concentrations. The Sulphur content

This work presents the results obtained during flotation of fine-grained apatite-bearing tailings provided from the Kovdor concentration plant in a laboratory cell and a pilot-scale column. Flotation studies were conducted on a sample containing >85 % particles passing 36 µm by using tall oil fatty acids in combination with polyoxyethylene cetyl ether (2 EO groups) as an alternative for nonylphenol

Sulfidic mine waste usually contains elevated amounts of valuable and hazardous metal(loid)s, which may pose environmental risks but can also provide opportunities for resource recovery. Reprocessing of mine waste can offer both economic and environmental benefits by supplying some of the ever-growing global demand for valuable metals, as well as reducing environmental risks. The present study aimed

The recovery of fluorine and iodine in the production and concentration of wet-process phosphoric acid (WPA) can not only reduce environmental pollution, but also increase the added value of production. In this work, the phosphate rock was digested with H2SO4, and the remaining H2SO4 in the WPA was removed with Ca(H2PO4)2, then the WPA was concentrated under vacuum and different temperatures. Fluorine

The mechanical properties of the constituent minerals in shale rock are fundamental to a better knowledge of multi-scale shale behaviors. It benefits the engineering applications and predictive physics modeling of the shale formation. In this work, nanoindentation testing combined with scanning electron microscopy - energy dispersive spectroscopy (SEM-EDS) were used to obtain the in situ mechanical

The mechanical properties of large-scale columnar jointed rock masses (CJRMs) after excavation would be reduced due to the unloading relaxation, in addition to its influence on the stability of underground caverns. Moreover, the cutting of the interlayer shear weakness zones through the cavern complicates the overall stability of CJRM, and brings challenges to the stability control of project. In view

Cyanidation is considered the most employed process to recover precious metals such as silver and gold. However, cyanide containing wastes can be hazardous for the environment. Therefore, the soil electroremediation technique was systematically studied to eliminate/degrade the cyanide contained in mining tailing dams using an electrolytic cell with cationic separator and cheap-stable carbon electrodes

The sticky residue left from purifying crude titanium tetrachloride (TiCl4) using organic reagent has been harmful to production equipment. In this paper, it was successfully solved via using co-purifying reagent, which was prepared by doping copper powder in organic reagent. The impurity content and whiteness of TiCl4 were the indexes which were used to determine the formula of co-purifying reagent

Evaluation of brittleness index (BI) is a fundamental principle of a hydraulic fracturing design. A wide variety of BI calculations often baffle field engineers. The traditional value comparison may also not make the best of BI. Moreover, it is often mixed up with the fracability in field applications, thus causing concerns. We, therefore, redefine fracability as the fracturing pressure under certain

Several derivative disasters such as ground pressure disasters and methane explosions can be caused by the hard roof in coal mines. For limestone roofs with fine integrity and extreme hardness, collapse is difficult and the effect of conventional roof control methods is limited. Acidizing reformation is an effective way to weaken the strength of roof strata based on acid-rock reaction. In this study

Three-dimensional rock fracture induced by blasting is a highly complex problem and has received considerable attention in geotechnical engineering. The material point method is firstly applied to treat this challenging task. Some inherent weaknesses can be overcome by coupling the generalized interpolation material point (GIMP) and the convected particle domain interpolation technique (CPDI). For

Physico-mechanical rock properties are typically investigated via laboratory tests using core samples. However, sample coring is time consuming and expensive. The longitudinal wave velocity in rock bolts embedded in a rock mass depends on the surrounding rock properties. Hence, the longitudinal wave velocity in rock bolts can be utilized to predict rock properties. This study presents the relationship

Many physical processes in the field of rock physics are influenced by the presence of fractures and microcracks. Therefore, intact rock samples are often used for reproducible experimental studies, and cracks are artificially created by various methods. For this, one possibility is the use of thermal treatments. In this work, twelve different thermal treatments are experimentally studied for dry Bianco

The grindability of raw material is generally determined by Bond’s standard ball mill grindability test (developed by the Allis Chalmers company). The ball mill grindability test is used for describing ore hardness and it is so widespread that the Bond Work Index generated from the test is often referred to as an ore characteristic. The ore resistance to grinding and energy consumption can be expressed

As the coal mining goes deeper, strong mining induced tremors frequently occur, which seriously threaten the safety of underground miners and ground residents, as well as the productivity and effectiveness of mining activities. The deep-hole blasting technology is expected to weaken or fracture the roof, thereby reducing the risk of strong mine tremors. However, the effectiveness of this technology

During high-intensity, fully mechanized mining of extra-thick coal seam, the top coal would cave to a certain 3D form. Based on the data collected during drilling, a 3D model of top coal caving surface space was established to determine the relationship between the location of the stope roof and the caving surface, enabling the mathematical computation of the top caving angle (φ). The drilling method

A novel neutralizing agent (PAdeCS) was produced from concrete sludge generated during the production of secondary concrete products by centrifugal molding, and the effect on actual acid mine drainage (AMD) was evaluated. The effect was compared with a conventional neutralizing agent (i.e., calcium hydroxide). Nine reaction tanks were temporarily installed and operated, imitating the treatment of actual

The phosphate ore flotation slurry process requires the addition of H2SO4 as a pH adjuster; this can cause the Ca2+ on the mineral surface to dissolve and combine with SO42− to form CaSO4, thereby changing the surface properties of dolomite. In this study, the effects of Ca2+ dissolution and CaSO4 upon the surface properties of dolomite in a phosphate ore flotation slurry system were investigated.

Magnetic interaction between magnetic particles is of great significance in the fields of magnetic separation and functional materials. A good understanding of interaction mechanism of magnetic particles would further boost its promising industrial applications. We hereby present our work which visualizes the movement behavior of magnetic spheres in magnetic fields employing high-speed imaging and

CO2 drilling is a promising underbalance drilling technology with great advantages, such as lower cutting force, intense cooling and excellent lubrication. However, in the underbalance drilling, the mechanism of the coupling CO2 jet and polycrystalline-diamond-compact (PDC) cutter are still unclear. Whereby, we established a coupled Smoothed Particle Hydrodynamics/Finite Element Method (SPH/FEM) model

This paper presented a novel bond-slip model to better reveal the mechanical behavior of the bolt-grout interface for fully-grouted rockbolts under tensile loads by considering the non-linear response in the softening stage. The exponential decay function is adopted for describing the non-linear response in the softening stage. Based on the improved bond-slip model, the corresponding analytical solutions

To achieve efficient separation of magnesite from quartz, a novel cationic collector—Dimethylaminopropyl lauramide (DPLA), was introduced into the quartz-magnesite reverse flotation system. The flotation performance and adsorption mechanism of DPLA on the minerals surfaces were investigated by micro-flotation tests, contact angle measurements, zeta-potential measurements, Fourier transform infrared

Aiming at the fact that joints in rock mass exhibit different spatial extension directions, uniaxial compression tests of rock-like specimens were carried out to investigate three-dimensional cracking and coalescence of two spatial-deflection joints. Based on the 3D reconstructions of specimen CT images, 3D cracking behaviour and ligament fracture pattern were investigated. The fracture evolution of

A sufficient database of measured flyrock ranges produced by blasting at a particular site can be used to determine the probability that flyrock will exceed any prescribed range. Such a probabilistic analysis is given for data from 6 sites (surface mines and quarries). A flyrock model based on two-dimensional (2D) ballistics, incorporating the site-specific blast designs, is also used to predict a

This paper describes a 3D cellular automaton (CA) for modelling ore pile formation that incorporates size segregation due to surface stratification. Ore stockpiles and bins are essential in mining operations as a buffer between the mine and the mineral processing plant, and their operation plays an important role in the overall performance of the downstream equipment. Size segregation can occur if

The anchoring eccentricity of the bolt and cable bolt is a common problem in geotechnical support engineering and affects the ability of the bolt and cable bolt to control the rock mass to a certain extent. This paper reports on numerical simulation and laboratory experiments conducted to clarify the effect of eccentricity on the anchoring quality of the bolt and cable bolt, and to establish an effective

Abstract not available

In the United States, sandstone-hosted ore deposits of the Paradox Basin (Colorado Plateau) are major resources of uranium and vanadium, two metals important to green energy among other applications. Despite historic and current mining interest, and their significance as major domestic resources of critical elements, the geometallurgy of these deposits has received little study. This article documents