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By W. J. Li, L. Kong, G. L. Li, X. M. Xi, J. Qiu

"A novel hydrothermal method was applied to prepare the precursor of LiMn2O4 using pre-treated electrolytic manganese dioxide (EMD) and lithium hydroxide as the main raw materials. The precursor was subjected to heat treatment between 400 and 900ºC to obtain spinel Li1.05Mn1.95O4 and Li1.035Co0.035Mn1.930O4 positive materials for lithium ion batteries. The structure and morphology of the obtained powder materials were studied in detail by means of X-ray diffraction (XRD) and scanning electron microscope (SEM). It is found that the precursor has an amorphous structure and a high reactivity, which is easily transferred to spinel structure during heat treatment, obtaining a positive material with an uniform structure and good performances. The XRD patterns reveal that single phase spinel Li1.05Mn1.95O4 can be obtained from the precursor after heat treatment at 600°C in air. The final Li-rich Li1.05Mn1.95O4 product obtained showed a well-defined stable spinel structure and distinctive crystal faces with particle size between 200 and 300 nm. The as-prepared Co-doped spinel sample exhibited a excellent electrochemical performance with an initial discharge capacity of 113.0 mAh/g and 93.8% of its original value was retained after 100 charge-discharge cycling at 0.5 C.INTRODUCTIONThe increasing demand for portable electronic devices and hybrid or full electric vehicles is driving the development of cheap, efficient, compact lightweight and environmental friendly rechargeable batteries systems (Chung et al., 2002; Scrosati, 1995). Lithium ion secondary batteries have satisfied this demand to a greater degree than other battery systems. The cathode material plays a critical role in the performance of Li-ion batteries. The high cost and toxicity of cobalt compounds for the cathode material of LiCoO2 has prompted a search for alternative materials. LiMn2O4-based spinels offer a potentially attractive alternative to LiCoO2, due to its abundance, low price, ease of preparation, environmentally friendly characteristics, better thermal stability, and its effortless recycling (Tarascon et al., 1991; Yabuuchi and Ohzuku, 2003; Amatucci et al., 1999; Tsai et al., 2003). Some achievements have been created to meet the requirements (Guo et al., 2010; Kang et al., 2005; Park et al., 2008; Takahashi et al., 2006; Lee et al., 2001; Yoshio et al., 2001; Arumugam et al., 2008). However, the largest obstacle encountered in the practical applications of LiMn2O4 is its fast capacity fading during long term cycling, which is due to Jahn-Teller distortion of the [MnO6] framework, the electrolyte decomposition at high potentials and manganese dissolution into the electrolyte (Fey et al., 2003). The electrochemical performance of LiMn2O4 is also strongly dependent on its morphological properties, such as crystallinity, phase purity, surface area, grain shape and particle size distribution, etc. All these morphological properties are closely related to the material synthetic routines and heat treatment processes (Huang et al., 2000; Myung et al., 2000; Takada et al., 1998)."

Jan 1, 2012

By Y. Thibault, L. Morin, R. Cameron, D. Gould

"There are an estimated 50 to 100 million dry metric tonnes of low-grade nickeliferous pyrrhotite tailings in the Sudbury area alone, with an average nickel grade ~0.8% (plus cobalt). Pyrrhotite is a highly reactive sulphide mineral that has the potential to generate acidity; consequently, it is stored in large tailings ponds that require perpetual treatment to avoid the production of acidic drainage. Re-processing this material using bioleaching technologies has the potential to recover valuable metals, while reducing the toxicity, reactivity, and acid generating potential of the remaining residues. CanmetMINING is currently developing a stirred-tank bioleaching process to recovery nickel and cobalt from pyrrhotite-rich tailings. Stirred-tank experiments have been conducted with one tailings sample over a range of pH and temperature conditions, resulting in 80 to 90% and 70 to 80% leaching of nickel and cobalt respectively in 10 days.INTRODUCTION Sulphide tailings may represent a significant financial liability for mining companies as these wastes may produce acidic drainage under some disposal conditions. As a result, the companies must post financial bonds large enough to ensure there are sufficient funds for perpetual management of these wastes. At the same time, there are billions of dollars in metals incorporated into these mining wastes waiting to become valorized. Many sulphide tailings are amendable to bacterial oxidation for metal extraction. Re-processing of tailings using bacterial leaching has the potential to recover valuable metals from waste; and reduce the toxicity, the reactivity, and the acid generating potential of the remaining residue. By reprocessing these wastes there is an opportunity to significantly reduce liabilities and financial assurance bonds, while recovering metal values. There are an estimated 50 to 100 million dry metric tonnes of low-grade nickeliferous pyrrhotite-rich tailings in the Sudbury area alone with an average nickel grade ~0.8% (Peek et al., 2011) plus cobalt and copper. Pyrrhotite is separated from pentlandite concentrates by magnetic separation and flotation. It is already finely ground and has often been segregated from other tailings material, making „mining? relatively inexpensive. This represents roughly (> $100/ton) in contained value, with negligible mining costs. This paper reports on the development of a stirred-tank bioleaching process for recovering nickel and cobalt from pyrrhoitite-rich tailings, which is currently underway at Canmet MINING."

Jan 1, 2017

By A. A. Brant

"Improving geological and geophysical evaluation should serve to reduce the early-stage risk assessment and there-by contribute to exploration expenditure stimulation. The limitations of present-day methods are reviewed, particularly as to anomaly causes, depth penetration and quantitative physical interpretative abilities. Some of the problems now under study are discussed. Future developments expected include the treatment of quantitized geologic and geophysical data, as well as continuing attempts toward computerized interpretation."

Jan 1, 1967

By Douglas R. Schmitt

In general, knowledge of the state of stress within the Antarctic lithosphere remains largely unconstrained due in part to Antarctica?s inaccessibility and because of the paucity of seismic focal mechanism solutions. As such, an important component of the ANDRILL project was to acquire new information on the stress directions and magnitudes within the upper crust. Extensive fracture mapping of the core and oriented ultrasonic televiewer logging were carried out to provide strong constraints on both stress orientations and the faulting regime. The first hydraulic fracturing stress determinations in Antarctica were also carried out to provide complimentary stress magnitudes. These measurements were accomplished using a wire-line transported hydraulic fracturing system consisting, essentially, of two synthetic polymer packers that were inflated to isolate the 1-m long pressurization interval. The tests were conducted at the end of the drilling and logging in a ~130-m section specially drilled below 1000 mbsf (nearly 1500 m from the rig floor) for hydraulic fractures. This zone was drilled primarily through competent, dense, and low permeability diamicts. The core fracture and televiewer logging information was used to site twenty separate measurements. Classic hydraulic fracturing pressurization records with unambiguous breakdown and fracture closure pressures were obtained in about half of the measurements. The remaining tests provided fracture propagation and closure pressures that are consistent with the classic breakdown curves, but they did not include a clear breakdown pressure and are indicative of the reopening of either natural or drilling induced fractures in the wellbore wall. The preliminary analysis of the results are in generally good agreement with the stress directions indicated by the core fracture logging and the stress regime suggested by the character of the drilling induced core fractures.

Jun 1, 2012

By Kamran Esmaieli

This paper investigates the behavior of ore pass walls under impact loads caused by material transiting through an ore pass. In particular it considers the influence of foliation in the rock mass surrounding an ore pass as both a triggering and accentuating cause of degradation. Based on empirical observations in several underground mines a numerical experiment was designed to understand the influence of rock mass foliation on impact-induced damage on ore pass walls. The distinct element method, and in particular the Particle Flow Code (PFC2D) was used to simulate three different rock masses surrounding an ore pass. Each simulated rock mass has similar properties but was defined by distinct dominant foliation (70o, 80o, 90o) along the foot wall. The numerical experiments investigated different scenarios whereby the walls were loaded by a projected rock fragment striking the foliated walls at a constant impact angle and velocity. The damage inflicted by the projectile rock fragment, on the foliated rock mass, was quantified using the number of impact-induced micro-cracks initiated on the ore pass wall. The results of the numerical analysis indicated that the presence of foliation resulted in greater damage zones in the surrounding rock mass. In addition, the extent of impact-induced damage to the ore pass wall increased as the angle of interception between the ore pass wall and the rock mass foliations decreases. This is in agreement with qualitative field observations.

Jun 1, 2012

By G. F. Trainor

The complex ore body at CNRL?s Horizon mine presents some unique challenges in managing ore and waste delivery. With 25m x 25m ore blocks shovels often take bucket loads from multiple blocks to fill one truck load. With CNRL monitoring 22 different qualities per material a precise calculation of the blended quality of ore on the back of each individual truck is essential to meet the daily blend requirements at the plant. Additionally, one of these qualities must be closely monitored and controlled at a singular level as delivery of certain grade and quantities can cause serious disruptions at the plant. The waste material also requires special handling and delivery for its use in dyke construction for tailings impoundment. Shale materials used in the construction contain high levels of saline that must be contained to prevent seepage into ground water. This paper will discuss how the use of Wenco?s survey-grade GNSS system on shovels, its dispatching algorithm, and fleet management applications give CNRL the ability and confidence to control and report on these three issues.

May 1, 2013

By G. Whittle, R. Peevers, P. Moryoussef

Enterprise optimization is a relatively new optimization approach to mine planning used to jointly consider all aspects of a mining operation affecting the mine planning process and related valuation. In this paper, it is applied at SEMAFO's Mana operations in Burkina Faso, consisting of several open pits and a proposed underground mine. The surface-minable ore is relatively shallow, and the pits are long and linear. The underground operations, as currently envisioned, will consist of a stoping operation accessed by two ramps from the surface. Power is a concern at this property due to local power being produced largely by diesel generators, and it has become one of the key optimization constraints. Other important parameters are the mining and processing rates, underground configuration and cutover elevation. Enterprise optimization was found to improve net present value for the Mana Operations property by simultaneously optimizing multiple parameters and constraints to arrive at an optimal pit and mining phase design, optimal cut-off grades over time, and optimal ore feed based on ore hardness, power constraints, and head wades. Reserves were expanded several times over the course of the study to improve the valuation of the mining operation and put SEMAFO in its present enviable position of ongoing reserve increases.

Jan 1, 2011

By K. Bowes, M. D. Maley, R. J. Ring

The Honeymoon Uranium Project is an acid In-Situ Recovery (ISR) mine in South Australia. It was previously operated for approximately 18 months before being placed on care and maintenance in 2014, it was then acquired by Boss Resources in 2015. Boss has been performing a number of studies to plan for reopening of the mine, including a successful field leach trial (FLT) in 2017. The current configuration for uranium precipitation at Honeymoon is a batch process. Whilst this achieves effective uranium recovery, the precipitates produced are often very fine, with poor settling and solid/liquid separation characteristics. Continuous precipitation, involving recycling of solids, has reportedly been successfully utilised in other operations to increase the particle size and density of the product, leading to solids that can be more readily dewatered, dried and drummed, with less fines and dust generation. However, no operational data are available from such operations.

Jan 1, 2020

By W. A. Jones

Purpose of Paper Geophysics is a highly developed science which has found a wide use in industry. Perhaps the most spectacular application has been in the field of oil exploration. It has been estimated that, up to the end of 1939, geophysics was responsible for the discovery of five billion barrels of oil. In 1944, the sum o $40,000,000 was expended for geophysical work in the search for new oil deposits. Although the metal mining industry has so far made comparatively little use of the science, it is becoming increasingly common for the exploration engineer or geologist to be required to co-operate with the geophysicist. Many papers dealing with applied geophysics have been published but in most of them advanced training in physics and mathematics on the part of the reader has been assumed. It is difficult for the average engineer to obtain a ready understanding of the equipment, field procedure, and scope and limitations of the science from the literature. The present paper attempts to describe briefly and in simple terms the principles underlying magnetic, self-potential, and electrical resistivity methods and their application to a field problem. Introduction Geophysics is concerned with the study of gravity, magnetism, natural earth currents, earthquakes, vulcanism, and many other natural phenomena. The methods, originally devised for the measurement, for scientific purposes, of the forces associated with such phenomena have been adapted to the search for buried deposits of economic value. If the body sought has large dimensions and distinctive physical properties, geophysical measurements may reveal associated, and in some cases quite characteristic, anomalous features. However, in many instances the mass cannot be indicated directly but has a common association with geological features which can be defined by physical measurements. Although such surveys cannot specifically identify oil, metalliferous minerals, or other commercially valuable substances, it is possible to delineate anomalous sub-surface physical features which, with the help of geological information, can be assessed as possible or probable indications of the body or structure sought. The nature and extent of the material causing an anomaly, and its economic importance, can only be determined by further exploration, such as drilling.

Jan 1, 1947

By M. Côté, H. Pépin, Y. Richer, C. Gingras

Rolls-Royce Canada has been nominated as a Rolls-Royce Center of Excellence for repair of fan blades in 2003. One of the challenges of the Rolls-Royce Canada Component Repair Center of Excellence team is to reduce cost and time of inspection while ensuring trace ability and quality of the inspection performed on the fan blades. In the context of the dimensional control process optimization, and following the positive conclusions of initial trials carried out in 2003, the technical authorities at RRC have selected the SPG data 3D(TM) technology as a development base for dimensional control programs. The main goal of this development initiative is to develop and support an inspection system to perform the dimensional control and inspection of different components at the Montreal Fan Blade Repair Center of Excellence. The final objective of the program is to build a server platform capable to support different inspection sites within the Montreal facility for the future. This paper presents the certification process of the technology according to the VDI-VDE 2633 certification standards and some results of the fan blade inspection program of the BR 710, BR 715 and TAY according to the JES 195 engineering standards specification.

Jan 1, 2006

By V. Vorontsov

Catalysts Mo-Ni-S were prepared by combining MoS2 and NiS in weight ratios 1:1, 1:2, 1:4 and 2:1, each of which was admixed with 5%wt Ag and 5%wt YSZ to increase three-phase boundary surface area of the electrode. For comparison catalysts comprising Co-Mo-S in weight ratio of 1:1 of CoS to MoS2 admixed with 5%wt Ag and YSZ and pre-sulfided NiMoO4 were made. The catalysts were examined for electrochemical oxidation of hydrogen sulfide in solid oxide fuel cells (SOFC) at 850°C temperature. The catalyst prepared from 1:1 (wt. %) NiS:MoS2 demonstrated highest performance. Current density up to 1,330 mA/cm2 and power density up to 300 mW/cm2 were achieved using pure H25 gas, which are the highest among the reported H2S-powered fuel cells ever published in the literature. Anode materials of different NiS:MoS2 ratios have been characterized by means of X-ray diffraction (XRD), simultaneous TG/DSC analysis and Neutron Activation Analysis (NAA). TG/DSC and NAA results show that addition of NiS and Ag increases fuel cell performance due to improved structure/integrity of the anode. It has also been demonstrated that MoS2 is a suitable anode material in H2S-powered SOFC, with high activity towards H25 oxidation and thermally and chemically stable up to 850°C.

Jan 1, 2005

By H. C. Gunning

Introduction Considerable attention has of late been attracted to the area surrounding Nimpkish lake, on northern Vancouver island, by the discovery of important rich copper deposits. In less than two years some 200 mineral claims have been staked in a small area, and at least two groups have very promising surface showings. During the summer of 1929, the writer spent one month investigating the general geology and mineral deposits of the region, and, although no detailed work has as yet been done in the field or in the laboratory, the importance of the mineral discoveries and the lack of geological information available to the public warrants a preliminary paper on the district. The district is, from a mining viewpoint, very accessible. Boats from Vancouver call at Englewood, in Beaver cove, four times a week. From Englewood, a first-class logging railway, operated by the Wood, .English Company, extends to the northeast corner of Nimpkish lake. The fifteen-mile trip from the north to the south end of the lake is made by boat, two tugs being maintained by the logging company. The whole trip from Englewood can easily be made in one day. The known mineral deposits lie immediately east of the southern part of the lake, four miles or less from the shore. A fair trail, four miles ? long, leads from the lake to the Nimpkish Copper group. Apart from this trail and an old logging railway grade which follows the east side of Klaanch river for several miles, no trails exist on the southeast side of the lake.

Jan 1, 1930

By M. Cai

"It is well known that Peak Particle Velocity (PPV) plays a critical role in triggering rockburst damage in burst-prone underground mines. To estimate the PPV distribution around excavations, advanced numerical modeling can be used. In wave propagation numerical modeling, velocity field is often assumed to be uniform around an excavation. However, it is observed that wave velocities near mine openings are not constant, but rather non-uniform. Wave velocity in a rock mass depends on many factors such as rock quality and confinement. In particular, confinement has a large influence on wave velocity. The confinement around an excavation is low at the wall boundary and increases gradually and reaches a constant value far away from the excavation boundary. Hence, stress redistribution due to excavation will have a profound influence on wave propagation in underground mines. A better understanding of the influence of excavation effect on wave propagation helps to interpret the field observation of rockburst damage and improve mine safety. For this purpose, a non-uniform velocity model need to be constructed and the influence excavation effect should be taken into account in numerical wave propagation modeling.In the present study, a non-linear velocity model is developed firstly by considering the influence of confinement on wave velocity. This model links wave velocity to confinement explicitly. A coupled numerical method is then developed and used to study the seismic wave pattern around excavations in underground mines. Two codes, FLAC and SPECFEM2D, are coupled in the analysis. The motivation of developing the FLAC/SPECFEM2D coupled approach is to take merit of each code, such as the stress analysis capability in FLAC and the powerful wave propagation analysis capability in SPECFEM2D. The coupling process is realized through three steps: (1) static stress redistribution around an excavation is analyzed in FLAC; (2) data for coupling analysis, such as non-uniform velocity field (based on the new developed velocity model), mesh, absorbing boundaries, etc., are generated by FISH functions in FLAC and passed to SPECFEM2D; and (3) wave propagation modeling is performed in the SPECFEM2D considering a fault-slip seismic source. Because stress redistribution around the excavation is considered, non-uniform velocity field for the SPECFEM2D model can be obtained and this is a notable feature of this study. Very large difference in the S-wave response in these two modeling approaches with uniform and non-uniform velocity fields can be seen from the modeling results.Using the FLAC/SPECFEM2D coupled modeling approach, accurate velocity models can be constructed and this in turn will help to produce accurate PPV distribution around the excavations. Accurate PPV contours can be used to identify high rockburst risk zones for improved dynamic ground support strategy."

Jan 1, 2015

By Y. Jin, H. You, H. Pang, B. Lin

Successful application of steam assisted gravity drainage (SAGD) on the recovery of land facies ultra-heavy oil in Xinjiang oilfield depends largely on shortening the preheating period with the aid of the micro-fracturing technology, which is conducted through controlled water injection to a pair of horizontal wells to create homogenously distributed microcracks in the zone between the two wells. The numerical simulation of this mechanical process is yet to be investigated. Up to date, there has been research work on rock mechanics during the SAGD production period of marine deposited ultra-heavy oilsands, but the counterpart research on land facies ultra-heavy oilsands of Xinjiang oilfield is left undone. In this regard, this study is attempted to perform numerical simulation of the fracturing process on land facies unconsolidated oilsands. With this objective, the study first investigates geological and physical identification of the field collected cores, then carries out mechanical analysis on laboratory triaixal test results, based on which numerical simulation of the fractured zone is performed. The simulation is applied through a finite element platform adopting extended Drucker-Prager constitutive model, with the parameters determined by experimental work. It is verified that hydraulic fracturing of unconsolidated oilsands generates a microcrack feature in terms of a dilative zone instead of linear apertures. The extent to which the fractured zone propagates is visually demonstrated based on the magnitude distribution of equivalent plastic strain or volumetric dilation. Evaluation of the connection of injection and production wells can possibly be determined by the expansion of the saturated region around each well. Finally, the implications on the efficiency of hydraulic fracturing in stimulation of the pay zone are investigated.

Jan 1, 2015

By D. Moronkeji, R. Maharidge, D. A. Curry, B. J. Davis, U. Prasad, J. Franquet

"Proper shale characterization is crucial in shale gas drilling, exploration, completion and production. Unlike porous sandstone and carbonate reservoirs, the challenge with shales comes from their micro- to nano-darcy permeability ranges and the anisotropy of their mechanical and hydraulic properties. Most porosity-dependent logs are not sensitive enough to capture the true behavior of shales. Consequently, mineralogy and other strength and stiffness-related properties must be determined to characterize magnitudes and variances in shale mechanical and flow properties. In addition, these properties must pass quality assurance/quality control (QA/QC) practices to give confidence in their use in subsequent log calibrations, during geomechanical modeling, or in fracture design models. This paper presents a technique to integrate shale properties that are measured by various methods, and a methodology to perform QA/QC on the data before application.Shale properties originate from various sources, including downhole and laboratory measurements. Physical samples for laboratory testing are usually limited to a few depths. Lab tests are often costly, and replicating in-situ conditions can be difficult or impossible. In addition, results frequently show wide scatter, reflecting inherent depth variability and lateral heterogeneity. Wireline logs provide nearcontinuous data, but rarely yield direct measurements of rock strength properties. Although geomechanical and fracture models use log data, calibrating it with reliable and previously verified lab-measured properties is important. This paper presents a process to perform QA/QC on lab-measured data using various crossplots.Ten mechanical, microstructural and physical properties are graphically displayed to visually characterize shale strength behavior in ambient and in-situ conditions, whether measured or modeled statically or dynamically. These properties are often sourced from different departments. The properties are integrated but are individually subject to the previously mentioned uncertainties. Pairs of property values are crossplotted and compared with correlations from the literature or previously established with qualified data from related formations. Conformance with these correlations gives confidence in the data, whereas outliers are flagged as questionable. Repeating the process with questionable data crossplotted against other parameters for the same depth highlights the property with the greatest uncertainty. The determination of its value is investigated to locate the source of the inconsistency and establish a more reliable value. Where this is not possible, the user has a rational basis for rejecting that property value."

Jan 1, 2015

By Hao Zhang

Site inspection is an important component of safety management system. In current practices, the inspectors evaluate the safety condition on a construction site with the assistance of a standardised checklist. However, the checklist emphasizes on evaluating the implementation of safety management system, but provides limited task-specific check items for assessing whether the individual construction tasks are conducted under safe condition and in a safe manner. To address this issue, the research presented in this paper aims to provide safety practitioners with comprehensive and taskspecific safety information to promote effective risk identification and facilitate strategic risk control during site inspection. Specifically, this research first builds a project-specific safety information database, which stores potential risks and control measures for each construction task. The research team then develops a mobile decision support tool to retrieve information from the database and support safer decision-making on site. The tool supports users in two ways: one is to provide daily risk checklists and risk control strategies to guide step-by-step inspection alongside the project schedule; the other is to let users input any safety-related keywords during the safety inspection process and the tool returns relevant safety information by applying text mining algorithms. It is ongoing research. This paper presents an overall research framework and discusses the progress in developing safety database and data retrieval concepts. The outcome of the project will help enhance safety management practices and reduce possible risky working conditions on a construction site.

Aug 1, 2013

By Malcolm Black

Introduction Before beginning to write this paper, I decided that I should first find suitable definitions of the words Sample and Sampling. The dictionary gives: "Sample.-A portion indicative of the whole"; and according to Baillie (1), sampling is "That process whereby a representative and comparatively small portion of material is selected from a large bulk, and preserved under such conditions as shall prevent contamination or avoidable alteration, with a view to the formation of valid conclusions regarding the suitability of the bulk for specified purposes". These comprehensive definitions are alike in substance, and indicate that unless a truly representative portion is taken, it is not a sample. Ore 'as mined' generally varies a good deal in composition, and, in crushing, segregation takes place. Some of the minerals present, due to differences in hardness and friability, break into smaller pieces than others, and, on reaching the bin, the coarse particles roll away, leaving the fines behind. The result of this segregation is generally quite noticeable on the conveyor feeding the mill, especially when the bin is nearly empty and the crushing plant shut down. Should the sampling period synchronize with either the coarse or the fines, the sample obviously would not be representative. I agree that this is rather far fetched, but I maintain that such a condition is possible. Assuming that a representative sample may be procured from the feed conveyor, the method of cutting it down for assay has considerable influence in maintaining the original condition of the sample. The finer the material is ground after each cut, the more uniform the sample will remain. To illustrate this point, let us take a quantity of fine sand and add, say, three grains of rice to represent metallic particles. We may mix this sample by any of the known methods, then cut it into four equal portions. It is obvious that at least one of the portions will be without a rice grain. But let us grind the three grains of rice into flour and proceed as before. Now there will be a much greater chance of including some of the rice in each portion.

Jan 1, 1935

By Yuyong Li, Liangman Zhang, Zhaolian Wang, Shun Wang, Ltd. Shandong Huate Magnet Technology Co., Fengliang Liu

"Introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements. Adopting 240°-270° larger magnetic element with multi-poles and magnetic pulsation, and combining the devices of multi-channel rinsing water and top flushing water and new style tank, HUATE® JCTN can improve another 2%-10% concentrate mFe% than the traditional MS without lowering the concentrate recovery rate. Thereby, it solves the uneasy concentrate upgradation problem of the traditional MS resulting from the magnetic aggregation. Now, JCTN has been successfully applied in more than 30 mines in Australia, China and Russia, e.g. Sino Iron of CITIC PACIFIC MINING MANAGERMENT PTY LTD. HUATE® JCTN can optimize the industrial processing line by: 1) improving the discarding rate before milling to discard the necessary tailing ASAP; 2) getting in advance the final concentrate after milling. One JCTN can replace many traditional MS in series. In some way, it can also replace the anti-flotation separation process.INTRODUCTIONWe’re writing to introduce a newly revolutionary magnetic separator - Raising Concentrate Grade and Decreasing Dregs Content Magnetic Separator Series JCTN (i.e. RCG&DDC MS JCTN). HUATE® JCTN is designed for rinsing, purification, desliming and thickening of the magnetic minerals as per different requirements."

Jan 1, 2016

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée."

Jan 1, 2017

By C. O. Swanson

Introduction It is thirty-odd years since I first entered the mining field by working underground at Anyox, which makes 1t clear that I can qualify as one of the older generation and claim the privilege of dealing in generalities and broad impressions. In this position I find it interesting to re~ view the salient changes that have taken place during the past quarter-century and indulge in some speculations concerning the future, with the hope that my comments may be of value to others engaged in the field of mining geology. As indicated by the title, the treatment is a perspective from a single viewpoint rather than an attempt to give a complete and impartial analysis. This plan, while deficient in some respects, has the advantage of being more specific than one based on .a. compilation of opinions. An additional advantage is brevity, which would be difficult to obtain on a subject of this scope if it were viewed from all angles. In conformity with the general plan, specific references to the literature have been avoided as much as possible, although a number of publications of general nature are listed at the end of the paper. This procedure is intended to give credit to the sources used without making them in any way responsible for the interpretation. The starting point for the discussion is the situation as it existed twenty-five years ago, when, as a recent graduate, I first had a fairly complete picture of it. However there is one impression of an earlier; stage that seems worth mentioning. In one of my first courses in geology the statement was made that some of the leading authorities of the previous generation, who guided geological thought at about the beginning of the century, were inclined to question the value of an association with mining. This attitude was no doubt exceptional, and certainly it was not adopted by the students who laid the groundwork for mining geology in North America. But its existence even in a limited circle is significant m showing how far the application of geology has advanced as the result of the investigations started during the first part of this century.

Jan 1, 1949