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By A. de Ville d’Avray, G. Guezennec, P. Wavrer, E. Braak

The aim of the European CEReS project was to develop an innovative copper recycling route based on the coprocessing of coal production waste by bioleaching and printed circuit boards (PCBs) from Wastes of Electrical and Electronic Equipment (WEEE). Coal waste is processed by bioleaching in stirred tank reactors, and the resulting bio-lixiviant solution is used to extract copper from PCBs pre-treated by catalytic cracking. Copper is then extracted using solvent extraction, stripping and electrowinning. The whole process flowsheet combines thermal, biotechnological, physical and hydrometallurgical operations. Once the process concept has been validated at laboratory scale, a simulator of the whole process has been built in the USIM PAC software platform. The tool enables to improve the analysis of the results of the lab-scale experiments and to design industrial-scale scenarios by simulation. The results of such simulations allow to estimate the economical interest and to perform environmental impact assessment. After presentation of the CEReS project objectives and main results, the paper describes the methodology used to build the simulator and define the scenarios corresponding to feasible process routes. The main results of the simulations are then presented with technical, economic and environmental point of views. INTRODUCTION Because of rapid technological innovations in the electronics industry, electronic waste represents the fastest growing waste stream in the world, especially in developing countries (Işildar et al., 2018). Meanwhile, the global copper demand is expected to go on rising in the future. As significant amounts of copper are present in end-of-life printed circuit boards (PCBs), it becomes a necessity to develop efficient copper recycling routes. Metal refining from e-waste is traditionally performed by pyrometallurgical processes. However, the hydrometallurgical processing of PCBs, which has been shown to be technically feasible at laboratory scale with a wide range of leaching reagents, could be a less energy intensive and more flexible alternative (Tuncuk et al., 2012). However, a large amount of leaching reagent is required to leach the metals from PCBs.

Jan 1, 2019

Presentation Overview ?WRDC Purpose and Activities ?Women in Trades, Technology and Operations (TTO) Occupations ?Factors in Successful Recruitment / Retention of women (VBNC) ?Recruitment and Retention Strategies ?Conclusion Women in Resource Development Committee (WRDC) ?Incorporated in 1999 as a Not for Profit Organization ?Based in Newfoundland and Labrador ?Works to Increase the Participation of Women in Natural Resource Industries ?Research (Using Gender-Based Analysis) ?Career Exploration Programs for Women and Girls ?Outreach and Advocacy ?Policy Development ?Public Awareness and Education ?Gender Sensitivity Training ?WRDC Educational Resource Centre

May 1, 2006

By S. McCarthy, K. E. Waters, A. Jordens

The beneficiation of rare earth (RE) element bearing minerals has become an active area of research as applications for these elements grow while the supply to non-Chinese consumers is restricted by export quotas. One of the most interesting beneficiation techniques for RE minerals is froth flotation as their unique chemistry suggests that collectors with a specific affinity for RE cations should be able to selectively recover these minerals. Existing literature, focusing mainly on bastnäsite flotation, identifies hydroxamic acids as excellent collectors for RE minerals. The high stability of hydroxamate-RE cation complexes is the explanation most often offered for the observed selectivity of these reagents in bastnäsite flotation however some research has also suggested that mineral solubility plays a crucial role in the success of hydroxamic acid flotation of RE minerals. This work investigates the interaction of allanite, a relatively insoluble RE-silicate mineral, with benzohydroxamic acid using zeta potential measurements and microflotation. The effects of Fe(III) and Fe(II) ions as potential activating ions (cations that form stable hydroxamate complexes) on benzohydroxamic adsorption to the allanite surface are investigated as a potential solution to promote hydroxamic acid adsorption. The results indicate that the optimum conditions for separation of allanite from quartz occur at pH 4 using FeCl2 as an activator for benzohydroxamic acid adsorption.

Jan 1, 2014

By D. Mas Ivars, K. Suzuki, J. A. Vallejos

"A comprehensive geotechnical characterization has been undertaken at the El Teniente mine to describe and determine the rock mass behaviour strength properties of the primary copper ore. The Synthetic Rock Mass (SRM) modelling approach is used to simulate the mechanical behaviour of this heavily and unfractured rock mass. The micro-parameters of the model have been calibrated against mechanical properties and scaling laws for intact rock and veins, in order to represent virtual samples of four different geotechnical units. Results can be used to predict the rock mass scale effects, anisotropy, and brittleness properties that cannot be obtained using empirical methods.INTRODUCTIONThe primary copper ore at the El Teniente mine is described as very competent and massive, given that it exhibits a brittle behaviour (Rojas, Cavieres, Dunlop, & Gaete, 2000). This description is coherent with the geological description of the rock mass, which does not have discontinuities match as the definition provided by International Society of Rock Mechanics (ISRM, 1981). Only faults can be classified as discontinuities, but they are widely spaced. The primary copper ore has a high frequency of veins, where the cooper mineralization is hosted, these vein network structures are known as stockwork. Soft veins containing weak minerals as infill (chalcopyrite and anhydrite) control the disassembling of the rock mass during caving (Brzovic & Villaescusa, 2007).Presently, there are mainly two traditional methods used to estimate the strength of the rock mass: 1) determination of the strength envelope of the rock mass using scaling parameters from laboratory tests and 2) using numerical modelling based on back analysis of previous experiences of failure observed and measured in mining or civil excavations. The primary copper ore of El Teniente mine has no fractures; therefore, it is difficult to determine a rating that would enable to scale laboratory data, such as, RMR (Laubscher, 1977) or GSI (Hoek, 1994). This is the reason why the first option is not valid unless the entry data is manipulated or adjusted in order to obtain reasonable results. The second option requires, in general, a good characterization of a previous failure event in the rock mass, which is not always available. In recent years, new techniques of numerical modeling have been developed (PFC3D, ELFEN, Abaqus). Those methodologies are the third way to estimate the strength of the rock mass, but they are still in development. Particularly, the concept of SRM developed by Itasca is implemented in this study (Pierce, Mas Ivars, Cundall, & Potyondy, 2007; Mas Ivars et al., 2011), aiming to capture the real behaviour of the rock mass."

Jan 1, 2015

By D. H. Schwarz

The performance of proton exchange membrane (PEM) fuel cells depends on catalyst layer composition and structure. Experimental observations reveal that state-of-the-art catalyst layers consist of microporous agglomerates of carbon-supported catalyst sites bound together by polymer electrolyte. In between the agglomerates are macropores which provide pathways for the transport of gaseous reactants. In this work, three-dimensional, multicomponent and multiphase transport computations are performed using a computational fluid dynamics (CFD) code (FLUENTTM) with a new PEM fuel cell module, which has been further improved by taking into account the detailed composition and structure of the catalyst layers using a multiple thin-film agglomerate model. In this model, it is assumed that thin films of polymer electrolyte and liquid water surround the catalyst sites. The results of CFD computations show that transport limitations associated with the thin film of polymer electrolyte and the presence of liquid water in the catalyst and gas diffusion layers have substantial negative effects on PEM fuel cell performance. Also, the results of computations with variable distributions for a given precious metal loading show that, in general, uniform catalyst loading provides the best fuel cell performance.

Jan 1, 2005

By Barton G. Stone

The mining and exploration industries have been using Geostatistics (Matheron, 1963) for the past forty years. It has been extensively incorporated into three dimensional block modeling software whose usage has reflected the growth in the use of personal computers since 1980. Because of the utility of geostatistical models in mining and production planning, much of the modern reserve and resource modeling is done by mining engineers, geostatisticians and geological engineers. Explorationists are initially less concerned with three dimensional models until such time as a deposit has been roughly delineated. However, the concept of regionalized variables in ore deposits deals with the effect of spatial correlations between data points in a three dimensional sample space and should be useful for optimizing the spacing of drill holes to allow maximum bang-for-the-buck in drilling programs. This paper examines three common deposit types (porphyry copper, VMS and intrusive gold) to examine whether geostatistical methods have been used to minimize drilling costs because of better understanding of spatial correlations. The three model types were chosen from publicly available corporate websites of Canadian based Junior Mining Companies. They include the Wolverine polymetallic zinc deposit of Yukon Zinc in Yukon, Canada; the El Morro Deposit in Chile (30 percent ownership by New Gold Mining Company, and the Fort Knox Gold deposit in Alaska and 50 percent ownership by Nova Gold Resources). Typically, individual mining corporations post their technical reports as CNI 43-101 reports on their corporate website as indications of the favorability or progress on their more exciting properties. Data considered for this paper was not collected or generated by the author, but the information was extracted from these publicly available sites and had a variety of authorship.

Oct 1, 2009

By J. B. Edwards

"The case is presented for the use of simulators for the computer-based training (CBT) of mining plant operators and for introducing them to automatically controlled systems. As well as their use in the classroom, the role of simulators is examined for ""on-plant"" use in trouble-shooting, fault-finding and maintenance of automatic systems. Case studies are presented showing how specific simulators are becoming established or have potential in the areas of automated materials handling, machine testing, setup and guidance. The evolution of scientific simulations into simulators of widespread practical use is discussed and present-day limitations of computer speed and graphics are considered. Related areas of research for the Canadian Centre for Automation and Robotics in Mining (CCARM) are identified.IntroductionCCARM's Commitment to Simulator DevelopmentAs automation is progressively developed and exploited in mining operations, there arises an urgent need to educate and train staff responsible for its introduction and operation in our mines and for its maintenance. For this purpose , an essential ingredient of an automation program is the development of appropriate mining system simulators for use by a wide variety of personnel. The author has been fortunate to have been closely involved with the development of automatic control systems for a variety of mining machines and mining systems in the United Kingdom. A key ingredient of the research phase in each case has been the use of simulation techniques. As projects have moved toward their commissioning and exploitation phase, the simulations have evolved into simulators tailored for use by machine operators and maintenance personnel. Illustrative case studies are presented later. The researach of the newly constituted Canadian Centre for Automation and Robotics in Mining (CCARM) will likewise involve extensive simulation, and the development of simulators (from the scientific programs) for use at the mine by operators and technicians will be given high priority in the Centre's over-all work program."

Jan 1, 1990

By Eugene Barsky

"At present, theoretical concepts of gravitational separation processes are mainly limited by the study of the interaction between a flow and a solitary particle. Then the main conclusions of this analysis are applied to a mass process. However, this analysis is absolutely insufficient, because some elementary phenomena such as the ingress of coarse particles into the fine product output and vice versa cannot be interpreted from its standpoint. It is also impossible to predict the results of the classification of a material with a specific granulometric composition on a specific apparatus on its basis.In the present paper, an extended model of the process is suggested. The model is based on the behavior of all the particles of a specific narrow size class, and not on that of an individual particle. Similarity criteria of the process, which were empirically derived previously, are obtained from the analysis of this model.INTRODUCTIONIn case of gravitational separation, a part of solid phase moves, as a rule, vertically upwards with the flow, while another part settles against the flow. This flow is extremely complicated and chaotic due to various random factors. Among these factors are mass interactions of particles with each other and with the apparatus walls, non-uniform character of concentration and velocity fields, turbulent vortices and local fluctuations, real particles shape difference from spherical one, etc.Particles rotation results in a transverse force (Magnus' effect). At the motion of a non-rotating particle in a non-uniform velocity field, a transverse force also arises (Saffman's effect).A great number of publications have been devoted to the account for all these factors in two-phase flows in recent decades. Very complicated models have been developed, but the problem has not been completely solved as yet [1, 3].At the same time, simplified models of the behavior of a solitary particle in a flow are being developed. Despite their schematic nature, such models often prove to be useful for establishing general laws of the process and its similarity criteria [1]."

Jan 1, 2016

By Craig Roberts

"While various methods are available to estimate a mining project's value, value is only established through a transaction. Comparable methods allow the value estimated for a mining project to be benchmarked against mining project values established in the market. Comparable methods thus are a key tool for ensuring value estimates are congruent with what the market would actually pay. For example, if the value estimated for a mining project using discounted cash flow analysis differs significantly from the value implied using comparable market methods, the valuator may be using metal price or discount rate assumptions that differ significantly from those the market is currently willing to pay for.The paper provides an overview of market comparable valuation approaches, and discusses some of the difficulties and limitations that arise in using these approaches. The types of market values that are typically utilised are discussed, including asset sale prices, share prices (market capitalisations), and values established in corporate mergers and acquisitions. Topics discussed include methods used in estimating a mining project's value based on the market value of the company that holds the asset, and limitations that arise because of unique features of mining projects and of companies that hold them.It is concluded that market comparable and fundamental (e.g. NPV) approaches to project valuation should not be viewed as alternative approaches to estimating project value, but rather can and should be integrated to derive a single value estimate based on both market andfandamental data. A method for integrating these approaches is discussed, and illustrated by example."

Jan 1, 2003

By M. H. Haycock

Introduction The property of Rouyn Merger Gold Mines, Limited, is in Rouyn and Joannès townships, Western Quebec, seven miles east of the town of Rouyn. Traversing it is the east-west trending Cadillac-Bouzan fault. Diamond drilling in 1944 and 1945 along a shear zone south of the fault indicated an ore deposit lying at the contact between sedimentary and volcanic rocks and dipping approximately 60° to the northwest. In the summer of 1945 it was decided to sink a shaft to investigate the indicated ore zone. In the immediate vicinity of the deposit, bed-rock is overlain by clay beds, in some places as much as 70 feet thick. Consequently, possible shaft sites were limited to those locations where overburden would not be excessive. The most favourable site was about 125 feet to the south of the ore zone as projected vertically from bed-rock to the surface. Accordingly, it was decided to sink the shaft at this point, with an inclination of 60° N. W., paralleling the dip of the ore zone.

Jan 1, 1948

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty types. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk / return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1989

By V. Omaynikova, A. Lossin, H. Salomon-de-Friedberg

In 2009, Aurubis AG and Teck Resources Limited, recognizing a growing industry need, joined together to advance and further develop technology to deal with arsenic-bearing copper concentrates in an effective and environmentally sustainable manner. The work that followed included extensive bench testwork and 3 months of continuous, fully integrated pilot campaigns on high arsenic-bearing copper concentrate as well as environmental testing, market studies and economic assessments. The success of the CESL Process in processing arsenic-bearing copper concentrates, at levels of up to 4.6% arsenic, has been previously presented. The present paper discusses aspects of similar, equally successful trials on copper concentrates with grades of arsenic approaching 12%. Key parameters to the successful processing of these types of concentrates are discussed. In addition, data on subsequent continuous, pilot gold recovery from the leach residues and the longer term stability characteristics of these residues are also included.

Jan 1, 2014

By Qingxia Liu, Mingbo Zhang, Hongbo Zeng

The shortage of freshwater has been a major challenge for mineral flotation in arid areas. When using high salinity water, certain electrolytes are detrimental to flotation while others can improve the flotability of minerals. In this paper, the flotation behaviors and contact angles of pyrite in both Milli-Q water and high salinity water were investigated using different collectors at various pH levels. Results show that the thionocarbamate has a less affinity to pyrite in different solutions under mildly alkaline conditions as compared with potassium amyl xanthate (PAX) and N-isopropoxypropyl-N’-ethoxycarbonyl thiourea (iPOPECTU). At high pH levels, the slime coating on pyrite surfaces, which is caused by colloidal precipitates of magnesium and calcium ions in seawater, was confirmed by SEM, EDX and in-situ zeta potential measurement. The slime coating of colloidal precipitates on mineral surfaces led to low recovery of pyrite at high pH levels. The study of flotation behavior of pyrite in high salinity water improves our fundamental understanding of mineral flotation in seawater.

Jan 1, 2015

By Mehmet F. Taner

"The East Sullivan Stock (ESS) is a small, composite felsic alkaline pluton of presumedlate Archean age in the Val d’Or mining district. Three main facies have been distinguished: mon-zonite sensu stricto, porphyritic monzonite, and green trachytic porphyry. This monzonitic group ofrocks is of relatively homogeneous composition with high abundances of Na2O, K2O, Ba, Sr, Rb, Zr,Mo and LREE. The alkaline ESS is distinguished from other igneous units in the Val d’Or miningdistrict, such as the Bourlamaque Batholith, by relatively high concentrations of Ba, Sr, Rb, Mo, Cuand Au. The ESS hosts many base (Cu, Mo) and precious (Au) metal occurrences, including: (1)porphyry style Cu-Au-Mo disseminated sulfde deposits, (2) Cu-Au deposits in volcanic rocks near the ESS contact, and (3) pyritic gold mineralization in east-west trending shear zones. The ESS is well defined by concentrical zoning on the aeromagnetic vertical gradient color map, and displays four linear trends, which are assumed to be structural lineaments, at 035°-055°, 320°-300°, east-west, and north-south. The main mineral occurrences related to the stock display a preferred spatial association with the east-west linear magnetic trends.The ESS is preferentially located along a major structure and was emplaced late in the evolutionof the Abitibi subprovince like other felsic alkaline plutons. This stock is similar to late-tectonic min-eralized felsic alkaline intrusions of the Kirkland Lake and Larder Lake mining districts in Ontario, and to the Allard stock in the U.S.A. which is associated with gold and base metal mineralization. Similarities also exist with younger alkaline plutons associated with Cu-Mo-Au porphyry deposits in the Canadian Cordillera, which formed in tensional tectonic environments. The felsic alkaline magmamay have formed by partial melting of deeply buried supracrustal rocks, concomitant with the development of deep fractures such as the Cadillac Fault. In such an environment, hydrothermal solutions carrying remobilized metals from deep supracrustal rocks may have deposited gold and base metals in structural traps. Plutons similar to the ESS should be good targets for mineral exploration. Copyright © 1996 Canadian Institute of Mining, Metallurgy and Petroleum."

Jan 1, 1996

By Trang T. Tran-Valade

With continually increasing energy prices, the mining industry has been on the search for new energy optimization technologies. One area that is garnering great interest is Ventilation-On-Demand (VOD). Prior to selection and implementation of a VOD solution, it is important to fully understand the mine requirements as well as its existing infrastructure and the interaction with other automation in place at the site. With this information, a business case can be generated including a cost versus benefit comparison for various control strategies. To assist in the development of the business case, this paper will identify key areas for consideration and recommendations for an implementation plan.

May 1, 2013

By Nathan Ferdinands

Outline Overview of Site and Partners ?MeanduMine ?Thiess?GroundProbe Technology ?Work Area Monitor (WAM) ?Software control ?Alarms MeanduMine King2East pit failures ?Background, and Northern Failure ?Southern Failure Recovery and conclusion

Nov 1, 2011

By A. J. Naldrett

"Sulphurization of peridotite, that is 'to say reaction between sulphur from an external source and iron and nickel in the silicate minerals of the peridotite or in partially consolidated magma, is believed to be the me-chanism by which the small iron-nickel sulphide deposits associated with the ultrabasic rocks of the Porcupine district have formed.The pyrrhotite-pentlandite ore at the Alexo mine, Dundonald township, is localized by a shear that closely follows the lower contact of a peridotite lens. In the past, to account for this orebody, the magmatic segregation hypothesis has been advanced on the basis of textural evidence and the presence of the sulphides at the base of the lens. The nickel sulphide de-posits of the Porcupine, however, are not characteristically found along the basal contacts of bodies of peridotite. Furthermore, this study has shown that textures formerly thought indicative of magmatic segregation have been formed in certain deposits by the selective replacement of silicates by sulphides.At the Alexo mine, very minor amounts of pentlandite and heazle-woodite (Ni3S2) occur in the peridot-ite hanging wall adjacent to the ore. These sulphides are interpreted as having formed by sulphurization, the sulphur involved coming from the pyrrhotite-pentla.ndite ore emplaced along the shear. This reaction aureole raises the question of the role of sulphurization in the formation of the main mass of the sulphide ore. The very localized equilibrium that has been found to exist between sulphides and silicates in deposits throughout the area, the results of nineteen sulphur isotope determinations, and the abundance of pyrite and pyrrhotite in the volcanic country rocks of the Porcupine indicate that these deposits were formed by sulphurization rather than magmatic segregation."

Jan 1, 1966

By Rodrigo Craig Cerello

The Brazilian economy has always presented a strong correlation with the mineral activity. Since colonization days, due to the territorial expansion caused by the explorers search for gold, mining in Brazil became a basic sector of national economy. Currently, the Brazilian mineral sector¹ estimates a 550% production increment (Figure 1A) in the last 10 years, reaching the US$ 50 billion value, reflecting the increased global demand for raw materials from mineral origin. According to the Brazilian Constitution², mineral resources belong to the Federal State and, consequently, their exploitation must be authorized, under penalty of engendering federal crime. Furthermore, activities of this nature are prone to cause environmental degradation such as, but not limited to, deforestation, pollution, soil deterioration and water contamination. The GPEMA represents the forensics group of the Brazilian Federal Police responsible for the technical analysis of traces related to crimes against the environment and consequently, illegal mining cases.

Aug 1, 2013

By A. C. Hatton

Doped SrCoO3.8 was found to be a promising material for use as a cathode component in intermediate temperature SOFCs. In this work, strontium cobaltite ceramics doped with 10 mol% to 90 mol% samarium were synthesized using the glycine nitrate process in order to study the electrical conductivity and thermal expansion at temperatures of up to 800°C. As-synthesized powders were deagglomerated, pressed and sintered at temperatures ranging from 1100-1250°C. The effect of temperature and composition on electrical conductivity and thermal expansion are presented and discussed.

Jan 1, 2005

By Robert B. Parsons

"One of the disadvantages of the federal government's idea of ""taxation by consultation"" is that it seems to take longer to enact new legislation. The proposed new rules for taxing automobile benefits is one example. Here is a ball which has been batted around between government and the public several times and still has not come down to earth. Fasten your seatbelts, there may be more to come. IntroductionThe draft legislation released on April 13 contains the details of the government's current proposals on car expenses and benefits. They differ significantly from the last announced position. Finance Minister Wilson has indicated that the release in draft form will provide an opportunity for the Commons Standing Committee on Finance and Economic Affairs (the Blenkarn committee) and other interested persons to comment before the legislation is introduced in Parliament. Accordingly, there may yet be revisions.Notwithstanding the prospect of further changes, the proposed rules generally come into force in 1988. While taxpayers may welcome some of these changes, particularly the increase in the tax-exempt allowance, many must be frustrated that, at this late date, the rules for the current taxation year are not yet finalized."

Jan 1, 1988