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By E. Vesely, A. Saxena

"SAG mill liners are designed for protecting the mill shell and providing lifting power for ore charge and grinding media. Due to the impacts from the charge and the grinding media, the liner experiences dimple, plastic deformation, strain hardening, fatigue, peening and final failure. Because of the collisional environment directly measuring such dynamical loads is extremely difficult if not impossible. In this study we tried to evaluate the liner failure risk by simulating the collisions of solid particles with mill liner using Discrete Element Method (DEM). DEM simulation has been proved to be a very useful tool in evaluation of granular flow and its impacts on the solid structure. But there are certain limits in DEM coherently, such as the number of solid elements, the computer runtime, etc. Here we first present the general feature of the particle-liner collision in terms of impact force and collision energy. Then the effects of parameter selection is discussed. Our simulations show the fatal collisional event of huge impact force is very rare and the collisional events of low impact is much more frequent. The fatal event may contribute most to the liner failure. The rarity of the fatal events may be missed in a short runtime simulation. This technical challenge combined with lacking of criterion to evaluate varying impact loads in fatigue problems may further complicate the evaluation. Should we use the largest impact force alone or we should use the more frequent events is an open question and requires more effort. In order to evaluate the quality of liner design, we proposed a relative comparison method. In the end we show the implication and application of this method in liner optimization by a work example. In particular, the effects of the charge level of grinding balls and their size on the operation performance is presented.INTRODUCTION Grinding is one of the most important and expensive steps of mineral processing. A variety of grinding mills such as rod mills, ball mills, semi-autogenous (SAG) mills and autogenous (AG) mills are being utilized for comminution of mineral ores (Gupta & Yan, 2016). Up to today, SAG mills and AG mills have been widely used to reduce operation costs and increase throughput. In an AG mill, a rotating drum throws larger rocks of ore in a cascading motion which causes impact breakage of larger rocks and compressive grinding of finer particles. Unlike AG mills, SAG mills use steel grinding balls to break ores of size quite small such that they cannot be easily broken in AG mill. SAG mill liners are designed for protecting the mill shell and providing lifting power for ore charge and grinding media. Due to the impacts from the charge and the grinding media, the liner experiences dimple, plastic deformation, strain hardening, fatigue, peening and final failure. Quality and performance of SAG mill liners play a fundamental role to enhance efficiency of grinding mills, because failure of liners is the major cause for unexpected breakdown (Banisi, Hadizadeh, Mahmoudabadi, & Eilkhany, 2006)."

Jan 1, 2019

By G. J. Borbely, E. A. Devuyst, V. A. Ettel

"A new method for oxidative destruction of cyanide in industrial waste waters and slurries, such as gold mill barren liquors, tailing slurries and flotation tailings has been developed at the Inca research laboratories. Rapid decomposition of cyanide and related species is attained by treating the waste waters with a mixture of S02 and air at controlled pH and in the presence of a small amount of copper which acts as a catalyst. The approach selectively oxidizes cyanide and metal cyanide complexes, and also removes iron cyano complexes which are not removed by alkaline chlorination.The new method is shown to be less reagent intensive and therefore more economical than alkaline chlorination for treating gold mill and flotation waste waters. INTRODUCTIONOver 90% of the gold mined in Canada is extracted from the ore by ""cyanidation"". Wastes from the process consist of tailings which contain free cyanide, cyanide combined with heavy metals, thiosalts and thiocyanates. Because of the concern over the effect of toxic cyanides on the environment, all cyanide containing effluents will have to be treated in the future to meet certain government set concentration limits."

Jan 1, 1982

By Craig Dirk

Agenda Applications of ?GPS ?Drill Navigation ?Cycle time monitoring ?UDS / Boom Stress monitoring ?Payload systems ?Laser Surveying Future Applications

May 1, 2006

By S. J. Prout, J. M. Lang, D. Lascelles, K. Sarinas

"There is a growing demand for ore characterization methods to support metallurgical development programs from a true geometallurgical perspective. Today, there are multiple automated mineral analysis systems on the market, many of which are based on conventional mineral liberation data. However, liberation data can be limited when assessing the floatability of a mineral to predict its recovery as it doesn’t consider the surface area available for collector absorption and bubble attachment; whereas mineral exposure measurements can. Using the First-Order Rate equation to predict the recovery versus time of variously exposed particles, a model has been developed to predict the recovery of copper sulphides at a particular grind size. This model provides the opportunity for the prediction of copper recovery and grade from multiple, small-scale samples. These predicted values can be imported into resource modeling software, and guide the domaining of geometallurgical units within the ore body. Data has been analyzed from various global copper porphyry systems and compared with actual flotation testwork.IntroductionAs part of the development of a mining project, resource estimation primarily focuses on the definition of the quantity and grade of the ore in the deposit; as the project evolves from preliminary economic assessment through to feasibility, the geological model is usually further populated with hardness and recovery data.The CIM Definition Standards (2011) identifies measured mineral resource as the part of a mineral resource for which quantity, grade or quality, densities, shape, and physical characteristics are estimated with confidence sufficient to allow the application of “modifying factors” to support detailed mine planning and final evaluation of the economic viability of the deposit as an asset. The modifying factors include, but are not restricted to, mining, processing, metallurgical, infrastructure, economic, marketing, legal, environmental, social and governmental factors.With market fluctuations, many investors in the mining industry have become more and more risk averse which has increased the demand for more reliable data to support these modifying factors. This has led to the widespread use of geometallurgy and statistical analysis to better inform the resource estimation. Geometallurgy is used to characterize ore variability and is especially useful for highly variable or strongly zoned deposits, several close deposits that will be milled together, projects requiring complex or new metallurgical approaches, brownfields or sight-of-mine exploration, expansion projects that exploit new, deeper or adjacent reserves, and projects with significant legacy drill core that are being re-evaluated due to new economic circumstances."

Jan 1, 2018

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By Thomas H. Heine

"The Rabbit Lake uranium deposit is located at 58° 11’00”N.. 103°42'36""W., close to the west side of Wollaston Lake, and approximately 800 km north of Saskatoon. The orebody is hosted by Aphebian Wollaston Group rocks, initially deposited as a series of shallow-water marine sediments consisting, in part, of carbonates and possible saliferous petites. Metamorphism during the Hudsonian Orogeny, peaking at about 1850 Ma, recrystallized the sediments to upper amphibolite grade paragneisses. This was accompanied by partial anatexis. The waning stages of Hudsonian orogenesis appear to be marked by minor granitic intrusive activity.The post-Hudsonian period was marked by a long interval of physical and chemical erosion, resulting in the unroofing of the Wollaston metamorphic complex. The entire region underwent extensive lateritic weathering under tropical to subtropical conditions. Carbonates were especially vulnerable and, in the Rabbit Lake area, suffered extensive solutioning with accompanying formation of collapse breccias. Old zones of weakness also underwent periodic reactivation.It was during this period that uranium was leached from the surrounding meta-sediments by oxidizing meteoric waters, and transported into the karsted and fractured rocks of the Rabbit Lake doline.Athabasca Group sediments eventually covered the deposit, their diagenesis taking place at about 200 °C and 900 bars. This allowed the partial to complete recrystallization of the initial mineralization, resulting in a minimum age of 1281 ± 11 Major ""first""-generation pitchblende. Periodic fault/fracture reactivation modified the hydrologic regime within the deposit, resulting in episodic mobilization and recrystallization of pitchblende and other uraniferous species. This is clearly shown in the open pit at the present time: uranium is being mobilized and recrystallized on damp pit walls as bayleyite and liebigite due to the modification of the hydrologic system by mining activities.The uranium mineralization occurs mainly as fracture fillings, coatings, and impregnations within breccia zones and intensely altered metasediments. Lesser mineralization is intimately associated with phyllosilicates which form the matrix of a carbonate-col/apse mega-breccia. The primary ore mineral is pitchblende, consisting of five generations, and from which a large suite of secondary uraniferous minerals have formed. On a gross scale the metal content of this deposit appears to be simple, consisting almost exclusively of U, but minor Ni, As, Cu, Se, Fe and Co are also present. The eastern limit of the mineralization is defined by a vertically-dipping microgranite dyke - breccia complex, containing high-grade uranium values. The orebody is truncated to the west and at depth by the Rabbit Lake reverse fault. Minor mineralization occurs as fracture fillings in unaltered plagioclasite in the footwall of the ore body. Precipitation of uranium from solution could have taken place by a number of processes. A mobile reductant (methane, carbon dioxide, etc.) may have been generated from graphite present in some of the host rocks of the orebody. Sulphides are also a common accessory and may have aided in the formation of a reducing environment. Phyllosilicates may have acted as adsorbants for uranium, allowing for its fixation. This metal has also been incorporated into the phyllosilicates themselves."

Jan 1, 1986

By Ross I. Kelly

Carbonate rocks are widespread throughout Ontario and provide raw material for more uses than perhaps any other rock type. The principal carbonate rocks that are used by industry in Ontario are Paleozoic era limestone and dolostone. Limestone is a sedimentary rock that is composed mainly of the mineral calcite (CaCO,) while dolostone, also a sedimentary rock, is composed mostly of dolomite [CaMg (CO,),l. The majority of the province's limestone and dolostone extraction occurs from Paleozoic era rocks located in southern Ontario. Calcite and dolomite are also found in Precambrian marbles, calcite veins and carbonatites, however, utilization of these rocks by industry has been less common. Calcite and dolomite-rich rocks are utilized for a wide variety of uses including raw materials for cement and lime manufacture, chemical and metallurgical stone, fillers and construction aggregates (Derry, Michener, Booth and Wahl and OGS 1989a). For some uses chemical and physical requirements are very important. In the manufacture of glass, for instance, the chemical requirements of source materials are very important and very stringent. In other uses physical criteria such as whiteness may be more important. Although carbonate rocks are quite plentiful within the province, deposits that contain high concentrations of calcite or dolomite are somewhat limited. For that reason, this paper focuses on deposits that are known to, or may contain, a high percentage of calcite and/or dolomite. The paper emphasizes potential sedimentary limestone and dolostone resources, as these are the carbonate rocks most commonly utilized by industry in Ontario.

Jan 1, 2001

By Guy Demers

"This paper defines the responsibilities and functions of the Maintenance Department, and its organization, physical and human assets, highlighting the unique operating problems. Due to the self-sufficient aspect of the Asbestos Hill Deception Bay project, the Maintenance Department cover-s fields that are numerous and very dissimilar: production, mobile, processing, service, power generation, fire protection, heating, water and sewage disposal equipment. Added to this, buildings, plant and camps, wharves and communications equipment all demand versatility, adaptability and expertise from maintenance personnel. Good maintenance practices are a necessity in this environment and are more critical than at southern locations; that is, high-quality replacement material, complete and well-controlled preventive maintenance, major repairs on a component-replacement basis, updated inventory, efficient training and permanent contacts with suppliers, combined with an equipment improvement program, updated specifications on lubricants, hoses, seals, filters, etc., are mandatory. The seasonal aspect of the operations applies a great deal of pressure on the maintenance team, as the production months do not permit major repairs. Short- and medium range planning and accurate evaluation of equipment conditions highly influence production efficiency. Maintenance control, planning and scheduling do not follow the accepted standard routines, as personnel turnover normally does not permit an accumulation of knowledge of the equipment history and condition by the •individual tradesman."

Jan 1, 1976

By K. G. Davies, M. J. Royea

"A major program of pillar recovery at the Sullivan mine has been assisted for the past several years by a concerted series of rock mechanics investigations. The object of these investigations is to measure the parameters of rock behaviour which influence pillar mining. This quantitative information is then used in the design of mining methods appropriate for various conditions.Instrumentation to measure absolute rock stress, changes in rock stress and the gross deformation of rock masses has been developed. Various instruments are described, as are instrument evaluation procedures and typical test results. The data from underground measurement projects have been used to modify pillar extraction sequences along re-treat fronts. Rock mechanics information from individual pillars has been incorporated into the design of mining methods to suit particular circumstances."

Jan 1, 1968

By W A. Bardswich

The numerous factors associated with the prov1s1on of satisfactory air conditions in hot and humid Canadian mines are described. The main heat sources are auto-compression and the actual flow of heat from the rock. Temperatures reach 97°F at a depth of 8,100 feet. Various methods used in coping with high temperatures are described, including the use of ice stopes and heat exchangers. Moisture control, desirable air volumes and velocities, sizes of airways and methods of distribution are important considerations. A comparison of the temperatures, humidities and types of airways of two deep mines should prove useful in the design of future ventilation systems. Introduction OUTDOOR temperatures in northern Ontario vary from a low of around -40°F in winter to a high of about +90°F in summer. The average annual mean temperature over a 12-year period was +35°F, with a summer mean of 54 o and a winter mean of 16°. Because of low outdoor temperatures, a number of northern mines must heat fresh air for underground ventilation in winter; others, with high rock temperatures, are faced with a year-round cooling problem.

Jan 1, 1965

By A. P. E. Dirige

The stability design of cemented backfills is normally conducted using conventional approaches. Analytical or numerical models, backed by trial-and-error methods, are the primary means used to describe or predict the support performance of backfills during mining. The stability of paste backfill free-standing faces is a major concern due to potential consequences to production, ore dilution and safety. Available analytical or mathematical models are developed based on assumptions of the failure modes that may occur when vertical fill faces are exposed during adjacent mining. Numerical modeling serves to provide an understanding of backfill strength and deformation behaviour. Such approaches offer inherent limitations and generally result in conservative designs. In this paper, centrifuge physical modeling was conducted not only for performance evaluation studies, including stability analysis, but to develop an understanding of the strength and deformation behaviour of paste backfill exposed faces when the adjacent ore zone is removed. The failure mode and mechanics of failure observed in the centrifuge model of a given prototype situation are discussed in detail. Centrifuge model results were compared to numerical modeling and it was concluded that a sliding block failure mechanism that resembles a circular slip appears to be the predominant failure mode.

Aug 1, 2013

By G. A. Bezuidenhout, J. Davis, S. M. Bradshaw, J. P. T. Kapusta, D. K. Chibwe

"This research work forms part of an assessment to complement the feasibility of implementing high pressure sonic injection into relatively small (2.25 m I.D by 3.66 m I.L) Peirce-Smith converters (PSC) used at Lonmin Plc. Work has been carried out to characterize the fluid dynamics of three-phase (air, matte and slag) fluid flow in these converters using Computational Fluid Dynamics (CFD) simulations. The investigation has been done to study the flow pattern of the three phase system at high air pressure injection achieving sonic velocity at the tuyere exit into the converter. The 2-D and 3-D simulations of the three phase system were carried out using the volume of fluid (VOF) and realizable k -e turbulence models to account for the multiphase and turbulence nature of the flow, respectively. These models were implemented using the commercial CFD numerical code FLUENT. A detailed study of the flow pattern has been presented in the form of contour plots and the results obtained are useful for understanding plume extension and velocity distribution, shear wall stress distribution, and phase distribution characteristics in the system. The results provide a basis for further development of sonic injection technology into relatively small industrial Peirce-Smith converters with the ultimate objective of achieving lower energy consumption, improved process efficiency and increased throughput of the converting process. INTRODUCTIONPeirce-Smith converters (PSC) have been used in copper (Cu) and nickel (Ni) making smelters for more than a century for the purpose of removing iron (Fe) and sulphur (S) chemically associated with copper-nickel mattes through exothermic oxidation reactions. This process is commonly referred to as conversion. In principle, conversion is a submerged injection process, where typically air (or oxygen enriched air), at subsonic velocity (typically < 150 m/s), is laterally blown into liquid matte (Cu-Ni-Fe-S system). Oxygen preferentially reacts with Fe and S to produce iron oxide (FeO), which is slagged off, and sulphur dioxide (SO2), which reports to the process off gas."

Jan 1, 2012

By Corby G. Anderson, Caelen D. Anderson, Patrick R. Taylor

"The United States contains a variety of domestic rare earth element mineral sources containing such as ancylite, bastnasite, monazite, and xenotime. Research has been performed to investigate the fundamental surface chemistry involved in the froth flotation of these minerals, and apply the knowledge gained to substantiate the results through experimental testwork on a domestically sourced rare earth ore. This paper will outline the fundamentals and literature of rare earth mineral flotation, review its industrial applications and provide some recent research updates.THE RARE EARTH ELEMENTSRare earth elements (REE’s) are a unique family of elements with nearly identical physical and chemical properties. They account for approximately 1/6th of all naturally occurring elements, but the entire group occupies only one position on the periodic table. These 15 elements make up the lanthanide series (atomic numbers 57–71), and all but one (promethium) occur naturally. In addition to these 15 elements, yttrium and scandium are also considered rare earths since they tend to occur in the same deposits as the rare earths and share similar physical and chemical properties as seen in Figure 1. In particular Figure 2 denotes, a cartoon of the subtle differences in each caused by the 4f atomic sub shell (Gschneidner Jr., 1964). These subtle differences result in very difficult challenges in the selective concentration and final separation of each rare earth. (Anderson, 2015, Kronholm, Anderson, Taylor, 2013)Rare earths are separated into two different subsections; the “lights” or LREE’s (lanthanum57 through europium63) and the “heavies” or HREE’s (gadolinium64 through lutetium71). Yttrium is generally considered a heavy rare earth since its ionic radius is close to that of the HREE’s, while scandium is not considered either a light or a heavy."

Jan 1, 2016

By George Langford

Introduction The fiftieth anniversary is, for an individual or a society, an appropriate time for a review of the past so that events and experiences may be viewed m perspective, and thereby serve as a useful guide to the future. In this review of mining geology it is proposed to set forth the situation as it was when the Institute was founded, and then trace the developments during three appropriate periods-the first from 1898 to 1918 the second from 1919 to 1939 and the third from 1939 to 1948. Mining activities were widespread in Canada in 1898 and some of the operations were considered large for their day. The total value of the metals produced in that year was $21,705,854, and in the case of five metals the output had a value in excess of one million dollars. In order of importance these were gold, silver, copper, nickel, and lead. The important producing areas were ova Scotia, Quebec, Ontario British Columbia, and Yukon. This diversification of the mining areas and the metals produced created an interest in mining throughout Canada, and was an important factor in making Canadians conscious of their mining industry. In the year 1898 geology was a recognized science. The principles of physical geology were well known, but the same cannot be said of economic geology and structural geology. Ore deposits and their occurrence had been studied chiefly in Europe. A great many important observations had been made but the theories linking these facts together were still m a formative stage. The same condition was true of structural geology. These two branches of geological science which are so important in what is now called &apos;mining geology&apos;, had not progressed far enough to be of practical assistance mining operations. For this reason, geologists were regarded as dreamers in ivory towers-a concept chat still lingers in the minds of those who have not kept abreast of the growth of the science.

Jan 1, 1948

By T. Joseph, E. Zheng, M. Curley

"Hydraulic transportation efficiency and production optimization are considerations in the surface extraction of Athabasca oil sand deposits. To reduce the dependence on haul trucks, it is possible to extend the hydraulic transport system to production faces using a mobile at-face slurry system (AFSS). The flexible arrangement of connected pipelines transports slurried minerals from the mining face to the processing plant. An experimentally verified mathematical model indicates the friction loss of oil sand slurry associated with the AFSS. Laboratory-scale testing enables extended analyses for examining pipeline slurry transport in an oil sands environment.RÉSUMÉ L’optimisation de l’efficacité du transport hydraulique et de la production sont des considérations importantes dans le domaine de l’exploitation à ciel ouvert des gisements de sables bitumineux de l’Athabasca. Afin de réduire la dépendance envers les camions de transport, on envisage d’étendre le système de transport hydraulique aux fronts de taille à l’aide d’un système mobile de transport des matériaux sous forme de boue à partir du front de taille (AFSS, de l’anglais at-face slurry system). L’organisation flexible des conduites reliées permet le transport de minéraux à l’état de boue du front d’exploitation jusqu’à l’usine de traitement. Un modèle mathématique vérifié de manière expérimentale indique la perte de charge par frottement des schlamms provenant du traitement des sables bitumineux associée à l’utilisation de l’AFSS. Des essais en laboratoire permettent de mener des analyses approfondies portant sur le transport de boues dans des conduites dans un environnement de sables bitumineux. INTRODUCTIONObjectives and scope of studyThe at-face slurry system (AFSS) concept has become a competitive means for materials handling to optimize haulage system efficiency and cost. The mobile and flexible arrangement of the AFSS introduces a unique set of hydraulic transport problems. This paper will focus on developing the mathematical models governing the friction and head losses within the AFSS concept.Background of the problemLarge-capacity shovels and dump trucks are increasingly used for excavation, loading, and hauling in the operation of surface mining. Production cost and efficiency optimization are demanded during the Athabasca oil sands (Alberta, Canada) mining process to secure North America’s energy supply. Increasing haulage distances, rugged terrain, and a constrained mine environment are conditions that will reduce the effectiveness of the shovel-truck haulage system (Frimpong, Szymanski, & Changirwa, 2003). In such conditions, the tire heat index and weight, distance, and time limits for truck haulage can be exceeded, simultaneously creating extreme tire wear and high maintenance costs. In addition to low production cost and equipment effectiveness, a mining environment also requires efficient waste-material recycling and distribution. Waste materials need to be recycled from the processing plant to a new destination such as a tailings dam, or replaced in mined-out areas such as backfill. The Athabasca oil sands configuration and location characteristics result in a mining environment that would benefit from flexible pipelines for constant production and an efficient waste-material recycling process."

Jan 1, 2017

By S. Nafisi

Permanent mould casting may be regarded as a near net shape manufacturing process where simple to very complex shaped engineering components are fabricated with high degree of precision in a metallic mould, In this group, High Pressure Die Casting (HPDC), have attracted more attention because of its production rate, where both liquid and semisolid metals (SSM) can be cast with high degree of precision and versatility. The SEED process, Swirled Enthalpy Equilibration Device, the new process for semi solid metals slurry production route, consists of two steps: The initial step involves extracting specified amount of heat from the molten metal to generate liquid-solid slurry, i.e, mushy structure, followed by drainage of remaining liquid to produce a compact free standing feedstock for rheocasting operation. In this paper, microstructural evolution during the process and some initial casting results of automotive components an also reported.

Jan 1, 2005

By E. Barsky

"Theoretical notions of mass transfer processes in cascade separation of bulk materials have not been adequately developed as yet (Barsky M.D. 1980). In this paper we have derived linear difference equation of the second order for a cascade with initial feeding top any stage proceeding from mass exchange regularities. The solution of these equations has allowed us to determine quantitative dependences of the material distribution over the cascade stages, which serve the basis of the method of predictive estimate of the process results. We have also examined the model of the material distribution coefficient formation at individual cascade stages.We have checked the adequacy of this model to experimental data. It is noteworthy that the obtained theoretical results are phenomenological, i.e. they can be applied to the processes of separation of different physical nature, e.g. of isotopes, liquid media, gases, etc.INTRODUCTIONRecently, the processes of cascade separation of bulk materials have found broad application in various industries. They ensure a high separation efficiency and high-quality composition of final products. Although specialized literature gives serious attention to cascade processes [1], their theory is not sufficiently developed yet. To achieve optimal organization of this process, we examine mass transfer in a cascade gravitational classifier with stages of identical design."

Jan 1, 2016

Iron deposits of every major type except laterite occur in Quebec, and form one of the major iron ore resources of the world. The five principal types of ore described are: (1) hematite-goethite masses derived from iron formation through the oxidation and enrichment of iron by natural processes; (2) taconites consisting of fine-grained iron formation; (3) metataconites composed of coarse-grained iron formation; (4) iron and titanium oxide minerals in massive or disseminateed deposits within gabbro and anorthositic rocks; and (5) replacement or contact? metasomatic magnetite deposits associated with complex silicate and skarn mineral assemblages. Most of the ore, although relatively low grade, is easy to concentrate. The physical properties of the ores that affect the choice and efficiency of beneficiation methods are described. The extent to which iron ore from this area can be utilized in the future will depend on the continued use and improvement of highly efficient methods of beneficiation.

Jan 1, 1964

By K. Huang

"Solvent extraction (SX) is one of the most effective techniques for the multi-metal separation. However, repetitive pre-treatment of feed-in solutions and/or multi-steps two phase equilibrating in conventional SX processes were always unavoidable due to the poor separation selectivity between those metals with similar physicochemical properties. In this paper, our recent efforts, aimed to develop a “Three Liquid Phase Extraction” (TLPE) strategy for one-step separation and selective enrichment of different metals respectively into three coexisted liquid phases, are reviewed. Various feasible “Three Liquid Phase Systems” (TLPS) are evaluated. The TLPE technique provides a potential possibility for multiphase extraction to separate multi-metals.INTRODUCTIONLiquid-liquid Solvent Extraction (SX) is one of the most effective techniques for metal separation and purification. Traditionally, extraction and separation of multiple valuable metals from the leaching solutions of complex ores, industrial wastes and byproducts have to face such difficulties that multiple target metals with similar physicochemical properties co-exist in the solutions, and therefore their mutual separation selectivities are very poor. In conventional organic-water two phase SX processes, repetitive pre-treatment of feed-in solutions including the adjustment of the solution acidity, removal of impurities and/or multi-step liquid-liquid two phase equilibration were always unavoidable (Wang and Chen, 2001). Only one of the target metals is obtained in each extraction step, therefore the whole separation processes for multi-metal separation are typically very long and costly.Liquid-liquid-liquid three phase extraction is a developing technique for separation of complex systems containing multiple target components (Tan, 2003; Shen, 2006; Yu, 2009). The technique is in fact a three-liquid-phase selectively partitioning of different target components through the control of phase-forming behaviors of extraction system to create a unique separation medium with three co-existed liquid phases. The separation selectivity of “Three-Liquid-Phase System” (TLPS) may derive from its three-layered liquid phases from up to down with different hydrophobic or hydrophilic environment, and therefore each phase has its own specific selectivity for dissolving of an individual component. In a well designed “Three-Liquid-Phase System” (TLPS), multiphase extraction and selective separation of different components respectively into three different liquid phases can be achieved by only one-step of extraction. Owing to its distinct advantages, “Three-Liquid-Phase Extraction” (TLPE) technique has found many potential applications in purification of various organic chemicals (Shen, 2007) and biological activities (Chen, 2002; Tan, 2006; Jiang, 2008), treatment of environmental wastewaters (Shen, 2006; Yu, 2009; Yu, 2010; He, 2012), extraction of valuable components in natural products (Liu, 2010) and separation of multi-metals in complex leaching solutions (Jin, 2009)."

Jan 1, 2012

By C. Fortin

ABSTRACT The subject of gold flotation has been reviewed extensively. Most of these reviews focus on the theories of gold flotation and the physical and chemical effects that may impact the efficacy of the gold flotation process. The current status of gold flotation chemistry as it is being applied in industry has not been widely addressed. This paper reviews current gold flotation practice and research advancements and discusses how these applications tie in with the current understanding of gold flotation chemistry. Survey results from worldwide gold flotation operations are analyzed. Potential future areas of gold flotation research are highlighted.

Jan 1, 2013