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By Scott D. Long

"Abstract-Grass roots exploration has an emphasis on good precision at low (sub-economic) concentrations of an element, in order to identify "anomalies" which may lead to drilling targets. Although it is wise to have well-defined quality controls in place during early stage sampling, the control procedures at this stage tend to be rudimentary. When a deposit warrants detailed delineation, the need for accurate geological characterization and assaying of ore-grade rock must be supported by appropriate quality control procedures.As a project returns more promising results, and the likelihood of the project warranting a prefeasibility study increases, it is time to tighten quality assurance requirements and quality control protocols. Delays in instituting adequate quality control and verification procedures may lead to costly remedial actions that can also delay completion of the prefeasibility or feasibility study. Sometimes, as a project matures, the quality control and quality assurance aspects fail to keep pace with the changing nature of the work: an increasing emphasis on precise and accurate assaying of oregrade rock.A resource model is like a house of cards. The foundation of the house is the geological observations, the sampling methods and the geological interpretations performed upon those samples. Upon the sampling, which includes all the sub-sampling steps of sample preparation, rest the assay results. The quality of the assays can be no better than the quality of the sampling. Good assaying technique will preserve all biases and imprecisions introduced during sampling and sample preparation; it cannot remove them. If the sub-samples and/or assays are bad and must be redone, all the succeeding levels of the house of cards must also be rebuilt, or at least patched up.From geological observations, a geological interpretation is built, the quality of which is critical to the construction of an acceptable resource model. Geological elements are difficult to assess, and are not discussed here; they are dependent upon the expertise of the geologists involved. Geological knowledge contributes essential quality control elements to resource/reserve determinations (Sinclair and Postolski, 1999; Postolski and Sinclair, 1999).This paper consists of five sections: (1) overview of quality control protocols, (2) maintaining quality control of databases, (3) quality control of drill sampling, (4) optimizing crushing and grinding requirements, and (5) quality control of assay data acquisition."

Jan 1, 1998

By D. A. Stokes

"In October of 1980, Fording's 15 000-ton capacity clean coal silo was put into operation. The silo was unique in that it was designed to allow the mass flow of material, coupled with a sophisticated computer-controlled dynamic loadout/weighing system.On May 1, 1982, an explosion, attributed to a methane buildup, devastated the top of the silo. .As a contingent plan to minimize the effect of the production loss the conveyance to the silo top was reconstructed and the silo' was back in operation by mid-June 1982, although the silo top was left open to prevent further methane buildup. As dust emissions occurred during loading ofthe silo, an extensive study was undertaken to establish dust control for the silo, while at the same time providing methane detection and control.The study, conducted for Fording by the Cambrian Engineering Group of Calgary, involved an extensive search and investigation of existing coal silos. The study concluded that there IS no universally accepted method of controlling methane emissions in coal silos.The study also produced a unique conceptual design for handling methane, while at the same time, protecting the environment . Fording's Clean Coal SiloThe silo, located at Fording Coal's Fording River metallurgical coal operation, is utilized for the storage and load out of cleaned thermally-dried metallurgical coal.The silo was constructed in 1979 and 1980 to reduce unit train loadout times and to facilitate the handling of “special shipments"" of coal. The silo went into operation in October 1980, under manual control and utilized computerized, automated loading by February 198I.The silo is 21 m in diameter and 76 m high, with a nominal capacity of IS 000 live tonnes. The coal storage portion of the silo is 21 m in diameter and 48 m high, utilizing 2 steep-angled hopper outlets allowing mass flow of the stored coal during train loading. Each hopper has a control gate and a discharge chute, one chute for bulk loading, the other for trim loading of coal into the rail cars."

Jan 1, 1986

By L. Nastac, Y. Xuan

"The metal-matrix-nano-composite (MMNCs) in this research work consists of an A356 alloy matrix reinforced with 1.0 wt. % SiC 50 nm diameter nanoparticles that can be dispersed within the molten alloy matrix via ultrasonic stirring technology (UST) and induction melting and stirring processing. The necessary ultrasonic parameters to achieve the essential cavitation for adequate degassing and refining of the A356 alloy as well as the optimum fluid flow characteristics for uniform dispersion of the nanoparticles into the A356 alloy matrix have been investigated in this study by using computational fluid dynamics (CFD) modeling with a magneto-hydro-dynamics (MHD) model and an UST cavitation model.The MHD model accounts for turbulent fluid flow, heat transfer and solidification, electromagnetic field as well as the complex interactions between the solidifying alloy and nanoparticles by using ANSYS Maxwell and ANSYS Fluent Dense Discrete Phase Model (DDPM) and a particle engulfment and pushing (PEP) model.INTRODUCTIONAluminum matrix nanocomposites can offer outstanding properties, including low density, high specific strength, high specific stiffness, excellent wear resistance and controllable expansion coefficient, which make them attractive for numerous applications in aerospace, automobile, and military industries field (Bozic, 2010, De Cicco, 2009, Elshalakany, 2014, Goh, 2006, Jia, 2013 and 2015, Liu, 2014, Reihani, 2006, and Su, 2010).As shown in literatures (Aki, 1999 and Mussert, 2002), it is highly advantageous to use nano-sized ceramic particles to produce metal matrix nano-composites (MMNCs) since similar ductility and higher strength with the metal matrix can be achieved. Currently, there are several fabrication methods of MMNCs, including mechanical alloying with high energy milling (Chen, 1997) , ball milling (Filho, 2003), nano-sintering (Groza, 1999), spray deposition, electrical plating, sol-gel synthesis, laser deposition, etc. The mixing of nano-sized ceramic particles is normally lengthy, expensive, and energy consuming.Ultrasonic Stirring Technology (UST) has been extensively used in purifying, degassing, and refinement of metallic melt (Jian, 2005, Khalifa, 2008, Eskin, 2002, Xu, 2004, and Meek, 2006) mainly because introducing the ultrasonic energy into a liquid will induce nonlinear effects such as cavitation and acoustic streaming. SiC nanoparticles are widely used as reinforcement particles due to their relatively good thermal and chemical stability. Ultrasonic vibration can improve the wettability between the reinforced nanoparticles and the metal matrix (Lan, 2004, Cao, 2008, and Yan, 2011), which will assist to distribute the nanoparticles more uniformly into the metal matrix. Ultrasonic cavitation in liquids causes high speed liquid jets of up to 1000 km/h. Such jets press liquid at high pressure between the particles and separate them from each other (Hielscher, 2005)."

Jan 1, 2016

By P. I. Laforest, M. S. Moats

"Antimony in smelted copper anodes has been shown to cause problems in electrorefining including brittleness of starter sheets. In order to improve deposit properties, a study was conducted examining the effect of anode chemistry on cathode ductility and electrolyte chemistry. Two industrial anodes with different molar ratios of As/(Sb+Bi) were used in laboratory electrorefining experiments with commercial electrolyte, and the addition of commercial glue and Avitone. The ductility of 21-hr copper deposits was evaluated by a 180° bend test. X-ray diffraction (XRD) and metallography were performed on unbent specimens to characterize the deposit structure. Increasing the anode As/(Sb+Bi) molar ratio from 0.54 to 3.8 resulted in an increase, on average, from four to eight bends to failure in cathode material produced. Significantly lower concentration of antimony (V) in the electrolyte was detected when operating with the higher molar ratio anode. The presence of (111) and (200) planes was noted in cathode material produced from the higher molar ratio anode suggesting that mixed growth character could be responsible for the observed increase in bend test results. The ductility of the starter sheet materials was improved by a higher anode molar ratio.INTRODUCTIONThe presence of antimony in copper electrorefining electrolyte has been reported to cause problems in cathode production (Hiskey, 2012; Peng, Zheng & Chen, 2012; Wang, Chen, Zhou-Lan & Lian-Sheng, 2006; Wang, Chen, Zhou-Lan, Wang, Xiao & Zhang, 2010; Wang, Chen, Zhou-Lan, Wang, Xiao & Tang, 2011; Wesstrom, 2014). To better understand the impact of antimony, laboratory scale electrorefining experiments were conducted using industrial inputs (anodes, cathodes and electrolyte). The influences of anode chemistry on the valences of antimony and arsenic in the electrolyte were monitored and correlated to physical cathode characteristics, such as a bend test to failure and crystallographic orientation.Commercially, starter sheets are produced by electrorefining impure cast copper anodes onto titanium blanks. The starter sheets are then hung in an electrorefining or electrowinning cell using loops of bent starter sheet material. These loops, in the absence of sufficient ductility, fail resulting in cathodes falling into the electrolysis cells. It is thought that the reduction in ductility can be related to anode composition; in particular, the molar ratio of arsenic to antimony plus bismuth As/(Sb+Bi). It has been stated that maintaining this ratio above 2:1 results in numerous improvements to electrorefining operations (Baltazar, Claessens & Thiriar, 1987; Kamath, Mitra, Radhakrishnan & Shetty, 2003; Krusmark, Young & Faro, 1995; Noguchi, Itoh & Nakamura, 1995; Wenzl, 2008)."

Jan 1, 2016

By G. Mucsi, J. Faitli, K. Bohács

"The authors developed an online tube rheometer to supplement a Netzsch MiniCer (Netzsch GmbH, Germany) stirred media mill in order to monitor online the rheological characteristics of the suspension and therefore the result of grinding during the process. Previously it was demonstrated that the above measuring system was working appropriately based on the preliminary tests. The product related stress model was applied for the evaluation of the grinding results. It was found that the suspension concentration and the change of the material properties during grinding, consequently the rheology strongly affects the grinding result, i.e. specific surface area, median particle size as well as specific grinding energy. The tested model limestone – water suspensions behaved Newtonian initially, then after a given grinding time their properties had changed and they become Bingham plastic. INTRODUCTIONStirred media milling now is a common practice to produce fine and ultrafine granular materials for different purposes. With an increasing demand of ultrafine powders for industries (Kwade, 1999), wet and dry ultrafine grinding has been increasingly used in various fields, such as minerals (Mucsi, Rácz, & Mádai, 2013)(Rácz, 2014), ceramic materials (Becker & Schwedes, 1999), pigments (Ohenoja, Illikainen, & Niinimäki, 2013), chemical products (Baláž et al., 2013), microorganisms (Kwade & Schwedes, 2002) and pharmaceutics (Afolabi, Akinlabi, & Bilgili, 2014). It is well known that suspension rheology affects the wet comminution of materials (He, Wang, & Forssberg, 2006a). The rheological behaviour of the suspension containing the ground particles might indicate the level of interparticle interaction or aggregation and therefore it is an important variable factor of the process control (Muster & Prestidge, 1995). The influence of the rheological behaviour of mineral suspensions on their grindability has attracted more and more interests and attention, especially on ultrafine grinding performance (He, Wang, & Forssberg, 2006b) (Bernhardt et al., 1999). However, there are still many issues concerning the machine and the process for the different applications. When grinding is effective and the particle size range decreases significantly, the circulating suspension is becoming typically non-Newtonian. The changed rheological behaviour and the increasing rheological material parameters can negatively affect the grinding efficiency; therefore it is an important issue. Ultrafine stirred media milling as well as solid-liquid two phase flow have been studied for a long time at the Institute of Raw Materials Preparation and Environmental Processing of the University of Miskolc. Regarding ultrafine grinding the research is focusing on the description of materials’ grindability (energetic aspects) both in wet and dry circumstances (Mucsi et al., 2013; Rácz, 2014). Concerning rheology, the three measuring pipes tube rheometer was developed decades ago (Faitli & Gombköto, 2015). So far many different solid materials from all over the world had been tested in this rheometer (Faitli & Gombköto, 2015). Main aim of these tests was to gain basic data for large scale hydraulic transport applications. Among the many stirred media mills there is a Netzsch MiniCer mill at the Institute. It was reasonable to combine the two fields together, and the goal of the research presented in this paper is to develop an online tube rheometer for the Netzsch mill and to carry out grinding and rheological testing simultaneously."

Jan 1, 2016

By D. C. R. Espinosa, P. Aliprandini, F. P. C. Silvas, J. A. S. Tenório, M. M. Jiménez Correa

"Nickel ores are divided into two types: sulfide deposits and lateritic deposits. About 60% of nickel resources are found in laterite ore, while the remaining 40% is contained in sulfide ore. Laterite ore is usually processed via pyrometallurgical means or through hydrometallurgical techniques that include acid leaching and metal value recovery from solution. In this study, copper and nickel adsorption by Dowex M4195 ion exchange resin from an acidic sulfate liquor was investigated. The acidic sulfate liquor was collected from an atmospheric leaching process (AL) of laterite ore. Ion exchange experiments were conducted in a batch system by varying parameters such as pH, time, metal concentration and temperature. Initially, mono-elemental synthetic solutions of nickel and copper were used in the experiments and then a synthetic solution simulating AL liquor was tested. Test results showed that the resin exhibited high selectivity towards copper and nickel, however, a high concentration of iron in the synthetic AL solution interfered with the recovery of nickel and cobalt by the resin.INTRODUCTION Nickel is one of the most important industrial metals in the world. It is widely used in industrial applications, such as the production of stainless steel, magnets, electroplating and special alloys (Dizge et al., 2009). The main sources of industrial nickel production are sulphide deposits; only 40% of industrial production uses lateritic ores. However, it is estimated that 60% of global nickel resources are found in nickel laterite deposits (Kuck, 2016). Since industrial nickel demand continues to grow, the development of new technologies for the extraction of nickel from laterite ores has become an interesting research topic (Agatzini-Leonardou, 2009)."

Jan 1, 2017

By André Bérubé

"IntroductionSince the disappearance of Les Forges du Saint-Maurice at the end of the last century, many historians have taken an interest in the lengthy past of this enterprise. They considered the political, socio-economic, administrative and anecdotal aspects of the industry, but barely dealt with the elements of technology. The purpose of this article is to try to fill this gapru.Les Forges du Saint-Maurice was an integrated industrial concern, specializing in the production of semi-finished wrought iron and finished cast iron, that operated almost without interruption between 1734 and 1883. Les Forges first came into being in 1729, when Montreal merchant Francois Poulin de Francheville submitted to the king of France a request for the right to exploit the bog iron ore deposits on his seigneury of Saint-Maurice. This request, agreed to in 1730, was one of a long series of attempts, previously unsuccessful, to establish a local iron industry in the colony. Several such proposals were held up by a lack of capital from promoters or a too rigid application of the mercantilist policy by the metropolis. In 1730, however, the French minister Maurepas favoured a more liberal policy which would encourage private enterprise. The benefits of an iron industry to the naval construction industry was a factor that caught the attention of administrators. The choice of the site for Les Forges was based on the following factors:• the abundance of surface deposits of bog iron ore in the Saint-Maurice region;• the presence of a vast supply of hardwood and conifers needed in large quantities by this industry;• the proximity of sandstone and limestone deposits, indispensable materials for the construction and operation of the blast furnace;• the presence of a water stream, with sufficient flow to provide the hydraulic power needed for the operation of the machinery."

Jan 1, 1983

By Godfrey W. McDonald, Dennis E. Fredrickson

"Commercial coal mining has been recorded in Nova Scotia since 1863 and during this period an estimated 60,000,000 short tons of mine discard containing 10 1030% coal has been accumulated, Approximately 70% of these dumps are in the Cape Breton region and most are owned by the Cape Breton Development Corporation (CBDC), formerly DEVCO.The explosion of oil produced energy costs which created an increase in thermal coal demand as well as the desire to rehabilitate abandoned mine dumps encouraged coal reclamation. CBDC was receptive to a proposal from the Selminco Joint Venture and encouraged the building of the Princess Recovery Plant (1980) and The Summit Plant (1982).The mine dump contains scrap, waste rocks, coal and substantial quantities of fine shale. The scrap and oversize are removed and the remaining material slurried with water to a density of 1.45. The slurry is cycloned to separate the saleable thermal coal from the rejects which are returned to designated areas of the dump for contouring and revegetation.BackgroundThe recorded coal production in Nova Scotia from 1863 to 1980 was 390,000,000 short tons. This extraction was associated with an estimated 60,000,000 short tons of discarded material. This mining discard and coal washing plant reject are located in numerous, varying sized dumps throughout the mining areas. Approximately 70% of these dumps are in the Sydney coal field region of Nova Scotia. The coal content of these dumps varies from 10 to 30% coal with an average of 18%.Energy CostsThe explosion o f energy costs in the mid-1970s greatly increased the sale price of thermal coal which made recovery of coal from some of the dumps economical. The environmental benefit of these operations will be the rehabilitation of the dumps upon cessation of the coal reclamation operation."

Jan 1, 1983

By Simon Houlding

"The objective of Part J of this paper is to identify the limitations of the traditional modelling methods and to illustrate, by example, the potential for error created by their application to complex deposits and mining situations. Part 2 describes the evolution of new, proven technology which eliminates these deficiencies and provides precise and practical alternatives. These promote the use of realistic geological and mining shapes and eliminate altogether the rectangular approximations of traditional methods.The Case for Precision ModellingIt is not the intent of this paper to promote the benefits of computer modelling per se. It is assumed that these are recognized by the mining industry in general. The concern of Part 1 is to identify, qualify and quantify (where possible) the limitations of the tractitional modelling methods. In many instances these methods continue to be applied to complex geological and mining situations for which they were never intended nor designed. The source and magnitude of the resulting errors, conflicts and inefficiencies are not always obvious, however, they can have far-reaching effects on the efficiency and profitability of mining operations.The conclusions support a rapidly growing demand by industry for practical, precise modelling technology which eliminates the deficiencies and can be applied with confidence to evaluation, design, planning and control of mine production in all situations. Part 2 describes new technology which has evolved in response to these industry pressures and has already been successfully applied to complex mining situations. This new technology can aptly be described as appropriate technology for the 1990s."

Jan 1, 1991

By J. Lu, D. B. Dreisinger, G. Houlachi

"Zinc metal is primarily produced by electrowinning from sulfate solution. Zinc electrowinning is very sensitive to impurities such as Co and Ni. These impurities have to be removed to produce high-quality zinc and maintain a high zinc current efficiency. Zinc dusts are used to remove these impurities by cementation. However cobalt cementation is extremely slow and it is typically activated by the addition of Cu and Sb. Even with the use of Cu-Sb activation, cobalt is still difficult to remove. The zinc dust used for cobalt cementation is negligible compared to that consumed for hydrogen evolution. In some plants up to 6-7% of electrolytic zinc is used for cementation. This is a great waste of energy. Cu-Sb activation is not well understood. The objective of this study was to further understand the Cu-Sb activation and then find a way to reduce hydrogen evolution and promote cobalt cementation. The investigation reveals how hydrogen evolution (or zinc dissolution) and cobalt cementation and re-dissolution change with temperature, zinc dust dosage, the concentrations of copper and antimony and time. In the Cu-Sb activation, copper is deposited on a zinc particle to produce a porous shell. The zinc particle as an anode dissolves while the shell as a cathode provides a place where cobalt cementation and hydrogen evolution occur and they are catalyzed by antimony. A certain level of antimony (around 0.1 mg/L) is a key to maintain the catalytic effect of the shell. At a higher antimony concentration, cobalt cementation is accelerated slightly while hydrogen evolution is increased greatly. When a zinc particle dissolves to a certain degree, cobalt loses its cathodic protection and starts to re-dissolve. The change in cobalt concentration is determined by the rates of cobalt cementation and re-dissolution. The operation conditions can be optimized to maximize the cobalt removal and minimize the zinc dust dosage.INTRODUCTIONMost of the world’s zinc metal is produced by electrowinning from sulfate media. Many impurities such as iron, copper, cobalt and nickel are co-extracted into solution with zinc. Iron, mercury, indium, lead and tin are removed by co-precipitation as hydroxides. Copper, nickel, cobalt, aluminum, arsenic and germanium are partially co-precipitated with iron while cadmium, magnesium and chloride remain in solution. Cobalt, copper, cadmium, nickel and etc. are subsequently removed by cementation with zinc dust to achieve an acceptable current efficiency and high purity metal product for the economical production of zinc. Zinc provides a strong thermodynamic driving force for the cobalt cementation:"

Jan 1, 2016

By ByongPil Lee, Changkyu Lee, Jin Gyun Park, Hyung Sub Eom, Sung-Koo Jo, Jae-Young Lee, Gilsoo Han

"A new hydrometallurgical process for nickel extraction from a low grade laterite ore such as limonite has been developed by RIST and POSCO. This POSCO Nickel Extraction Process (PosNEP) consists of five main processes: ore reduction using hydrogen as a reductant; acid leaching at atmospheric pressure and temperature; cementation by the use of reduced-ore seed; production of the main product such as ferronickel or a high purity nickel compound; and production of by-products such as cobalt and iron in the forms of cobalt sulfate and iron oxide. In addition, hydrogen produced in acid leaching and hydrochloric acid regenerated in pyrohydrolysis for iron oxide production can be reused in the process, which makes PosNEP more cost-effective. The performance of PosNEP has been proven through pilot tests, showing that this process is economically and technically viable. In this paper, basic concepts and detailed test results of PosNEP are shown.INTRODUCTIONNickel has been extracted from two types of ore, sulfide and oxide ore. Nickel and cobalt usually occur together in the ores. The principal ore mineral of the sulfide is pentlandite, (Ni,Fe)9S8, which is easily beneficiated to produce sulfide concentrates(Moats & Davenport, 2014). These concentrates are usually treated by smelting and converting to make a matte. The produced matte is then purified through either hydrometallurgical or pyrometallurgical processes to produce high-purity nickel. In general, this process for sulfide ore has been known as a more cost-effective process than that for oxide ore.The oxide ore is laterite comprised of two different ore types, saprolite and limonite. The main nickel-bearing mineral of saprolite is nickeliferrous garnierite,(Mg,Ni)6Si4O10(OH)8, and that of limonite is nickeliferrous goethite (Fe,Ni)O·OH ore (Moats & Davenport, 2014). Since the saprolite has high contents of nickel and slag formers (MgO and SiO2) and a low content of iron, it tends to be treated by a pyrometallurgical smelting process such as calcination and electric furnace techniques to produce ferronickel for use in stainless steel. In this process, the cobalt in the ferronickel does not have any economic value."

Jan 1, 2017

By D. V. Krefting, D. R. Bennett

"The Cyprus Anvil Mining Corporation established a lead-zinc mine and concentrating plant at Faro in Yukon Territory in 1969. Following some 12 years of continuous operation from a single pit adjacent to the concentrator, the company decided to expand operations into two additional areas on the Vangorda Plateau. The two new deposits, known as Grum and Vangorda, are located some 15 kilometres from the existing concentrator.Confirmation of mining feasibility was followed by determination of the most practical and economical method of transporting the raw ore from the new mine sites to the existing concentrator. This analysis was carried out in two phases. The first phase reviewed the feasibility of alternative transportation systems on an 'order-of-magnitude' cost basis. This work identified systems worthy of more detailed examination. The second phase examined the preferred alternatives in greater detail.Initially, operating principles and parameters were established and catalogued. Then, based on these criteria, complete systems were developed utilizing alternative modes of transportation . In the overview analysis, some transportation modes were judged impractical and discarded, 'order-o f-magnitude' costs were developed for other systems and the most costly were eliminated . In the detailed study, the favourable systems were examined in depth which required development of accurate capital and operating costs, consideration of environ- mental impacts and an assessment of intangibles associated with the operation of a new development."

Jan 1, 1984

"SART technology is a useful tool for improving the economics of gold recovery from certain types of complex gold ores. SART liberates cyanide consumed by base metals such as copper, zinc and nickel, and enables the newly freed cyanide to be recycled to precious metals leaching while producing high-grade base metal sulphide concentrates for sale. The benefits of SART include the reduction in cyanide consumption, avoidance of cyanide destruction costs, minimization of risks of environmental non-compliance due to residues of cyanide destruction reporting to mine effluents, and generation of extra revenue from the sale of base metal concentrates. Concerns with SART typically include uncertainties around capital and operating costs and proper integration of SART into the overall metallurgical flowsheet. This paper presents two case studies addressing these concerns. The first involves actual costs of the full scale SART integrated into a gold heap leach operation and treating up to 500 m3/hr of leach solution at a mine in Mexico. The second involves field pilot testing and a preliminary cost estimate for integrating SART into a silver mine in Peru using Merrill Crowe.INTRODUCTION One of the current trends in the gold industry globally is the increasing importance of complex polymetallic gold deposits as discoveries of large Carlin type gold deposits become increasingly rare (Sceresini, 2005). The presence of cyanide soluble copper and zinc in complex gold deposits necessitates changes in traditional gold extraction metallurgical flowsheets. One of the tools available to the industry to help deal with interferences of cyanide-soluble base metals in gold extraction is the SART (sulphidization-acidification-recycling-thickening) process. SART breaks the weak acid dissociable (WAD) base metal-cyanide complexes, precipitates the metals as high-grade sulphide concentrates and makes the freed cyanide available for recycle. Although SART is a commercially available technology, it is still relatively new to the industry. Fewer than ten (10) full scale plants have been constructed in the past couple of decades. Some of these SART plants are small, most are located at remote sites, and the majority have not operated on a continuous basis. This has resulted in a general lack of information in the industry about the true costs, operability and metallurgical performance of SART. BQE Water has been involved in the design, construction, commissioning and operation of large scale SART plants in Mexico, Turkey and Chile and has conducted field testing programs as part of the technical assessment of SART integration into various metallurgical circuits. Having built and operated numerous plants utilizing selective sulphide precipitation of heavy metals, BQE Water has gained unique insight into the design and control of the sulphidization stage of SART to minimize costs and ensure high efficiency in cyanide recovery."

Jan 1, 2017

By H. Weissenbaeck, B. Nowak, M. Oesterreicher, R. Stastny

The producers of certain metals like nickel and cobalt increasingly face a shortage of easy-to-mine and easy-to-process ore bodies. Their focus is shifting towards alternative raw materials which in turn demand new, different extraction techniques. One potential route for processing a ferrous ore with a non-ferrous target metal is atmospheric leaching with hydrochloric acid followed by purification of the pregnant leach solution (PLS). For the separation of iron from the PLS, and, in turn, the extraction of the non-ferrous compounds, the following flow sheet is proposed. Pre-concentration of the PLS, oxidation of ferrous (if present) to ferric chloride, hydrolysis of ferric chloride leading to the precipitation of hematite and the evaporation of hydrochloric acid, followed by crystallization of non-hydrolysable metal chlorides by means of sparging hydrogen chloride into the solution. Hydrogen chloride required in the latter step is produced internally by super-azeotropic distillation of regenerated hydrochloric acid. The liquid filtrate from the crystallization step is recycled to hydrolysis. Depending on the specific composition of the PLS, the hematite produced contains only traces of other impurities, whereas the crystallized mix of non-hydrolysable metal chlorides – containing also the target metal in enriched form – contains ferric chloride only in an amount referring to the filter cake moisture. These crystals can then undergo further hydrometallurgical separation and extraction processes. As an example, this flow sheet is proposed for treating nickel laterite ores. Experiments related to the demonstration of crucial assumptions in the flow sheet are presented. Based on those experiments a mass and energy balance of the flow sheet was calculated and is presented here together with a table of the major consumables in order to provide a basis for an operating cost estimate and other process economics.

Jan 1, 2016

By T. Sun, J. Kou, C. Sun, China Railway Resources Group Limited

"The polymetallic sulfide ore in Jiama county of Tibet contains 0.78% Cu, 0.046% Mo, 0.31 g/t Au and 17.9 g/t Ag in average. However, heavy loss of valuable metals was observed using high-pH process and Butyl xanthate as the collector. In this paper, the flotation was optimized through the adoption of a novel collector C-7, which is a mixture of xanthate ester and thionocarbamate. This collector showed better flotation performance under weak base conditions. The recoveries of Cu, Mo, Au and Ag increased to 93.24%, 84.60%, 78.13% and 75.41%, respectively, under 15 g/t of C-7 at pH of 8.0. The adsorption mechanism of C-7 was investigated by micro-flotation tests, zeta potential measurements, FTIR analysis and adsorption quantity measurements. Chemisorption of C-7 on chalcopyrite surface is demonstrated with adsorption density 3.8 times higher than on pyrite.INTRODUCTIONXanthates are the most commonly used collectors of strong collecting ability for separating copper sulfide minerals from gangue in froth flotation. However, the selectivity of xanthates themselves is poor to realize separation of chalcopyrite and pyrite whose floatability are quite similar (Heyes & Trahar, 1977; Chandraprabha, Natarajan, & Modak, 2004). High pH process with xanthates as collectors is proved effective in copper-sulfur separation and is widely used in treatment of copper sulfide ore flotation (Smith, 1996; Valdivieso, Cervantes, Song, Cabrera, & Laskowski, 2004). This method could get ideal separation results, but large amount of lime must be added, and could bring about increased cost, device corrosion and environmental pollution. In addition, there could also be high depression and heavy loss of associated noble metal such as Mo, Au and Ag. Consequently, a large amount of research has been conducted on substitutions of xanthates for selective flotation of copper sulfide ores under low pH conditions (Gholivand, Khodadadian, & Ahmadi, 2010; Li, 2010)."

Jan 1, 2016

By Wengui Su, Qi Zhang, Junce Wang, Zhijun Ma, Xingyuan Weng

"Mesoporous materials with large specific surface area, pore size, and pore volume have been widely used in many fields such as ion exchange, gas separation, adsorption, and catalysis. Mesoporous materials prepared using natural zeolite have the advantages of both acid and alkali resistance. In this work, mesoporous materials were prepared using natural zeolite as the starting material and diethylenetriamine (DETA) as a template. The resulting samples were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and N2 adsorption-desorption experiments. The influence of the crystallization temperature and crystallization time on the specific surface area, pore volume, pore size, and morphology of the resulting mesoporous materials are also discussed. Our results show that for an increase in both the crystallization temperature and time, the average pore size first increases then decreases, while the specific surface area first decreases then increases. Based on this work, we concluded that the optimal crystallization temperature was 2003 and the optimal crystallization time was 60 h. These conditions gave an average pore size of 17.93 nm, a pore volume of 0.048 cm3g-1, and a specific surface area of 16.48 m2g-1.INTRODUCTIONMesoporous zeolite, as the name implies, is a highly porous crystalline zeolite. This material is of interest due to its high hydrothermal stability, its adsorption and diffusion properties for macromolecules, and its excellent selectivity and activity as a catalyst. In recent years, it has become a hot spot among research of porous catalytic materials and has been widely used in petroleum and natural gas processing, fine chemical processing, various adsorption and separation tasks, and other uses (Carvalho & Urquieta- Gonzalez, 2015; Teh, Triwahyono, Jalil, Mukti, Aziz, & Shishido, 2015)."

Jan 1, 2016

By S. Usui, Y. Shinohara, C. Tokoro, K. Horiuchi, S. Owada

Process optimization of heating and physical separation for Cobalt (Co) recycling from spent lithium ion battery (LIB) was investigated. LiCoO2 in spent LIB was transformed to LixCoO2 which was more easily decomposed than LiCoO2 by heating. Coexisting materials of aluminum and carbon, and sealed atmosphere of the LIB promoted LixCoO2 decomposition. In an atmosphere of Argon, 95 % of LixCoO2 in the spent LIB was decomposed to 76 % of Co oxide and 19 % of Co metal in 10 min at 823 K; a lower temperature than the theoretical value for LiCoO2. The Co oxide and Co metal exhibited magnetic properties and could be recovered by wet magnetic separation. Furthermore, slow heating was effective for grain growth of Co oxide and Co metal. At 2 K/min rate of heating, average grain size of Co oxide and Co metal were 239 µm and 28 µm respectively, whereas at 30 K/min they were 190 µm and 15 µm respectively. Therefore, separation efficiency for Co recovery by wet magnetic separation was increased when spent LIB was slowly heated at 2 K/min.

Jan 1, 2015

Fatalities Incident Four people perished May 15 ? 17, 2006 ??Doug Erickson ??Bob Newcombe ??Kim Weitzel ??Shawn Currie Incident details available at: ??http://www.mediaroom.gov.bc.ca/sullivan_mine/ ??sullivan_mine.htm Outline Immediate facts/observations from incident ?? #1 Shaft Waste Dump closure program ?? Technical investigations under Panel guidance ?? Findings to date and direction ?? Broaden awareness of potential risks

May 1, 2008

By A. McIntyre, L. R. Plitt

Both the Bond and the Hardgrove grindability tests are widely used in the mineral industry to measure the ease of the comminution displayed by a material. The Hardgrove test is mainly used for coals, whereas the Bond grindabifity test is mainly applied to hardrock minerals. The Bond grindability has the advantage that it can be empirically related to the energy required for comminution (work index), whereas the Hardgrove grindabifity test has the advantage of being easier to perform. In an effort to establish a valid correlation between work index and Hardgrove grindability, a series of parallel grindability tests were carried out on a wide variety of rocks and minerals. The standard Hardgrove test was modified to allow for materials with a higher density than coal. A new, satisfactory relationship was established which permits rapid estimation of work index from Hardgrove test data.

Jan 1, 1980

By Susan W. Campbell, Bruce Regensburg

"The CIM Careers Task Force has addressed industry's concern of a perceived shortage of skilled personnel over the coming decade. The industry is faced with a fundamental shift by young Canadians away from scientific and engineering careers, coupled with the fact that today 's students know little about the minerals industry and have a poor image of it.The responses to two questionnaires which were distributed to CIM members, government, professional associations, and educational institutions, formed the backbone of the Task Force position paper, which presents a shopping list of ideas and initiatives for consideration and to facilitation by the various organizations concerned.Tackling the image of the minerals industry is part of the answer to the careers crisis. On the positive side, the minerals industry provides the allure of a treasure hunt for young people and is seen as a significant contributor to the economy. It is understood to be well paying, provide good opportunities for advancement, individualism, and travel, and to be rich in esprit de corps. Enhancement of these positive aspects of the image can take place at all student age levels.Numerous initiatives tackle the negative aspects of the image. Young people perceive the industry to be environmentally damaging, which is the most crucial aspect that needs to be addressed. The industry is seen as still in the pick-and-shovel days and as a sunset industry that is running out of ore. Work in the minerals industry is perceived as dangerous and lacking glamour. And finally, the perceived remoteness of operations and exploration is seen as a drawback to a largely urbanized student group.Tackling young peoples' curiosity and interest in the minerals industry throughout grade school and encouraging postsecondary science and engineering students to enter the minerals industry by ensuring summer employment is the second part of the equation.The CIM Careers Task Force position paper develops strategy to attract and maintain interest of students in grade school, junior high, senior high school, and in post-secondary levels. The strategy outlines initiatives targetted at each of the educational levels and action plans to accomplish the objectives."

Jan 1, 1993