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By F. A. McLean

At the Annual Western Meeting held at Blairmore, Alta., October 1924, the writer presented a paper drawing attention -to the advantages of portable gas-driven equipment for developing isolated mining properties. This type of equipment was at that time practically in its infancy and the details of results actually accomplished were somewhat meagre. During the last year or so a number of these plants have been installed so that it is now possible to offer more definite information regarding the actual mining progress accomplished with such plants and their cost of operation in various parts of the country. This paper has been written with the idea of reviewing the work done during the past year, and to supply data which may be of interest to those wh9 are confronted with the problem of selecting equipment for development or assessment work. Because drilling operations play such an important part in mining, one of the first problems that usually confront the prospective? mine owner is the selection of the proper com-pressed-air plant. The size and type of equipment and the method of driving it require careful consideration. The size and type of equipment is determined largely by the funds available, transportation facilities, and the speed with which the programme of development is to be carried out. The selection of the proper method of drive usually depends on local conditions, such as the relative cost of various fuels, and has an important bearing on operating costs.

Jan 1, 1926

By Heikki Laurila, Sirkka-Liisa Jämsä-Jounela, Jarkko Karesvuori

"Artificial Intelligence includes excellent tools for the control and supervision of industrial processes. Several thousand industrial applications have been reported worldwide. Recently, the designers of the A1 systems have begun to hybridize the intelligent techniques, expert systems, fuzzy logic and neural networks, to enhance the capability of the A1 systems. Expert systems have proved to be ideal candidates especially for the control of mineral processes.As successful case projects, an expert system based on on-line classification of the feed type using neural data analysis is described in this paper. The essential feature of this expert system is the classification of different feed types and their distinct control strategies at the plant. In addition to the classification, the expert system has a database containing information about how to handle the determined feed type. This self-leaming database scans historical process data to suggest the best treatment for the ore type under processing. The system has been tested in the Outokumpu Finnmines Oy, Hitura mine. Other projects have been reported to be in progress.INTRODUCTIONIn the past ten years considerable researches have been done in the application of artificial intelligent methods in process industry. The technologies of fuzzy logic, neural networks and expert systems have received several thousand applications worldwide: monitoring and analysis of process operations, fault diagnosis, supervisory control, feedback control and scheduling and planning of operations. Recently, the designers of these systems have begun to hybridize these intelligent techniques to enhance the current capability of expert system. Complex signal processing, neural networks, fuzzy logic and rule-based systems are also implemented to develop new so-called smart or intelligent sensors, actuators or components. Field buses are playing a more and more important role in automation systems and in imbedded systems. The development of field buses has allowed the distribution of smart components over networks."

Jan 1, 2000

By Paul Hughes

This paper summarizes current underhand paste backfill mining as applied to Goldcorp Inc?s Red Lake Mine, Newcrest Mining Ltd?s Kencana Mine and the Lanfranchi Nickel Mine as well as ongoing research at the University of British Columbia?s Norman B. Keevil Institute of Mining Engineering. The Red Lake Mine utilises a 6 m wide undercut with a 2 MPa unconfined strength paste in order to selectively mine its high grade, high-stress orebody. Kencana?s orebody is located in a poor rock mass environment. An 8 m wide, 2 MPa unconfined strength paste sill allows a safe working condition for its high grade orebody. The Lanfranchi Nickel Mine utilises a cable-supported, 2 MPa paste, with 12 m span sills, to optimize the mining of the squeezing rock mass. This paper details the rock mechanic hazards, ground support techniques, paste practices and unique conditions for each mine. Further, an update of ongoing research at the University of British Columbia, focussing on the optimization of safe mining in underhand cut-and-fill mining in high-stress/weak rock masses, is presented.

May 1, 2011

By J. D. T. Steyl, C. A. Biley

"The chemistry of electrolyte systems containing iron remains generally poorly understood despite their prevalence in many natural and industrial processes, particularly in hydrometallurgy. These systems are typically challenging to study and model due to their affinity for complex formation and precipitation even at low pH. Recent developments in the hydrometallurgical processing of nickel laterites at Anglo American have called for a deeper understanding of the fundamental chemistry of the Fe2(SO4)3–FeSO4–H2SO4–H2O system. This paper details the development of an internally consistent, Pitzer ion-interaction model of this system, with explicit recognition of important contact ion pairs (CIPs). The primary application of this model is a thermodynamic framework for the interpretation of kinetic processes occurring during iron(III) reduction with SO2. Adopting a rigorous thermodynamic basis for the system chemistry facilitates the formulation of simple rate expressions that are capable of inherently capturing complex effects. While the iron(III) reduction case study remains the focus of this work, the developments have more universal applications and the thermodynamic speciation model can be extended into other systems containing acidic ferric sulfate.INTRODUCTIONIron is present in nearly all hydrometallurgical refining circuits typically as both a necessary and unwanted impurity and needs to be removed and disposed in a safe and efficient manner. This is generally performed by precipitation to form a range of solids such as hematite, goethite or jarosite. Numerous studies in the open literature have focussed on the removal of iron from refractory gold sulfide ore (Berezowsky & Weir, 1989; Berezowsky et al., 1991) and zinc pressure leaching (Buban, 1999; Ismael, 2003), and PGM matte sulfide circuits (Dutrizac & Monhemius, 1986). Moreover, since ferric iron is a strong oxidizing agent, it has been used extensively as a leaching agent for sulfide minerals (Dreisinger, 2006). Given the outlook of challenging economic conditions, declining ore grades and increasing levels of impurities, effective iron management is going to become increasingly critical to all hydrometallurgical processes.Against this background, and considering the widespread importance of acidic iron sulfate systems throughout natural and industrial processes, it is unexpected that the knowledge of the fundamental solution chemistry of these systems contains such significant gaps, particularly at the conditions typically found in hydrometallurgical applications. Existing literature describing the measurement and modelling of solution speciation in these systems have highlighted their significant chemical complexity (Magini & Caminiti, 1977; Magini, 1979; Lee & Tavlarides, 1985; Stipp, 1990; Papangelakis et al., 1994; Gil et al., 1995; Majzlan & Myneni, 2005; Kormanyos et al., 2008; Yue et al., 2014). Partially responsible for the lack of quantitative speciation measurements is the strong tendency of ferric to hydrolyse at even low pH (Flynn, 1984), complicating the laboratory study of such systems. Moreover, the large number of aqueous species that may co-exist simultaneously makes the study of individual species and the modelling of the numerous interactions between these species extremely difficult (Dry & Bryson, 1988; Stipp, 1990; Majzlan & Myeni, 2005; Kobylin et al., 2007)."

Jan 1, 2016

By Bjarne Ekberg

"The most economical way of dewatering mineral concentrates is to reduce the moisture content in the material mechanically using thickeners and filtration avoiding thermal drying whenever possible. In addition to this, the dewatering process should produce low moisture cake, high quality liquid, consume little energy. As a part of the dewatering process The CERAMEC® capillary filter has been proven to meet these requirements in over 150 installations. The filtration is done by using ceramic filter plates with small pore size. The capillary action in the filter medium secures gas free filtration at good vacuum, and due to the small pore size, filtrate is crystal clean and particle free. The energy consumption is minimal. This paper will discuss results from filters installed at Pyhäsalmi Mine Oy in Finland where the technology was has been used since the late eighties. Results from more recent installations like Los Pelambres in Chile and LKAB in Sweden will also be discussed.INTRODUCTIONThe idea of using capillary action to make dewatering more efficient was invented two decades ago. Ten years later whole filter plants utilizing the new method were delivered to mine concentrators for dewatering of mineral concentrates. Further development of ceramic membrane plates made it possible to meet the requirements in iron ore dewatering. In addition to low cake moisture, high capacity and low energy consumption, there are a lot of environmental advantages in using capillary filtration. One of them is clear filtrate.CAPILLARY FILTRATIONA micro-porous filter material behaves like a large number of narrow capillaries forming a network. When a pressure difference ?P is applied over the wetted, hydrophilic pore with the radius r, the force striving to push the water out of the pore will be ?Ppr2. The force striving to hold the water in the pore will be the vector force 2pr? cosa of the surface tension ? and the cosine contact angle a. Equalling those forces and solving the equation for ?P we get"

Jan 1, 2003

By Terry Keough

Contents for discussion ?Current liner technology ?Innovation of magnetic products ?Development of magnetic wear liners ?Installation and change out method ?Uses and capabilities ?Internal wear liners ?Summary Vulcanized rubber ?Many of you are familiar with using vulcanized rubber to provide wear protection on mining equipment. For years, this was the standard for most mining equipment, and mines spent a lot of money fabricating and lining steel equipment.

May 1, 2010

By Andy Fortin, André Vien, Christophe Bouché, Jeff McKay

"The technology and equipment design of the Twenty-first Century permit us to exploit low-grade ore bodies with milled tonnages reaching 300,000 tpd. Because of their substantial operational costs (energy, wear parts, etc) and precarious economic situations, the operations of today must maximize their metallurgical performance.The implementation of an Expert System becomes a logical avenue to pursue in view of increasing plant performance.Many operations, following the implementation of an Expert System, meet the objectives they determined before its integration; such as increased tonnage, stability, decreased costs, etc. However, they often cannot develop the full potential of the system due to certain factors that have been neglected or omitted during the implementation of the system.Three main elements have been identified during the implementation phase at INMET Mining Troilus Concentrator: 1- Instrumentation & Control 2- Software 3- Integration. Even though they have been clearly identified, these elements are often neglected due to lack of resources or lack of comprehension on the part of the operations personnel. This document will demonstrate, based upon our experience at Troilus and that of Metso Minerals, that we can identify and handle many factors which influence the profitability of the Expert System, for both short and long-term process control improvements.INTRODUCTIONThe Inmet Troilus Mine is an open pit mine, situated 175 km north of Chibougamau in the province of Québec, Canada. The mill, which started production in November of 1996, was originally designed to treat a gold – copper ore at a rate of 10,000 tpd.In early 1998, the mine plan called for a pit pushback and decreasing head grades for the following two years. With the price of gold nearing decade lows, the Troilus project was facing a major economical setback. There was a sense of urgency to reduce operating costs below the market price of gold. The mill team presented a project to management calling for an increase in mill throughput while minimizing capital expenditures and operating costs. This idea was supported by the existing mine plan, which called for a mine cut-off of 0.7 g/t Au and stockpiling low grade 0.5 g/t material for future milling."

Jan 1, 2003

By Sebastián H. Troncoso

Open pit mine planning is normally based on the selection of an economic envelope that has been generated by the Lerchs & Grossman algorithm, which requires individual economic valuation of each block of a geological block model. The selected envelope, usually called Final Pit, is later discretized in pushbacks and benches, which correspond finally to the fractions that the production schedule will allocate in time. This planning methodology has been widely used by the mining industry in countless projects to exploit open-pit mines, however, in many of the deposits can be found some undesirable elements such as arsenic, phosphates, ash among others that tend to reduce the value of elements of economic interest, either by disrupting the processes of concentration or as deemed impurities that affect the quality of the final product. Thus, a fair amount of blending would be required to capture the real value of the ore body. The traditional approach under estimates a block value by penalizing the block value by the amount of contaminant even when at the mine a set of blocks is amine at a time. This paper proposes a methodology for computing cut off grades over time that would maximize net present value allowing blending that should fulfill a set of metallurgical constraints. Preliminary results show significant increases in value and reserves quantity, questioning the use of fixed cut-off grades in generating a production schedule when blending applies to fulfill a set of geometallurgical constraints. Finally, the model allows the authors to show the importance of having adequate planning tools that will lead to the ability to look at the potential economic value of a mineral deposit.

Oct 1, 2009

By K. S. Kalenchuk

Massive landslides display complex deformation processes. For instance, slope movements of the Downie Slide, monitored using borehole inclinometers, extensometers, and survey monuments, show considerable spatial and temporal inconsistencies in the displacement rates. This study assesses the influence that inferred shear surface geometry, as a key factor contributing to variable slope movements, has on resolving spatially discriminated slope deformations in three-dimensions. Borehole data defines the shear surface location at discrete points within the slide and therefore, the shear surface geometry for the extent of the slide must be largely inferred. A series of three-dimensional numerical simulations have been run to assess the effect of different interpretations of the shear surface geometry. This investigation illustrates the importance of rigorous geospatial definition of slip surface geometry and the value of three dimensional modelling.

May 1, 2009

By Neri Roux, Chris Budgell, Allan Cramm, Leo Cheung

"Anaconda Mining Inc. is investigating potential improvements and expansions to their operating plant located on the Baie Verte Peninsula in Newfoundland. An extensive batch and continuous bench scale testing program was launched to investigate the efficiency of cyanide destruction under different conditions in order to improve tailings handling. The primary objective of the cyanide destruction study was to apply new technologies to develop a novel cyanide destruction system.Effluent and slurry from Anaconda Mining Inc.’s Point Rousse Project was received at RPC where test work was conducted. Various sodium metabisulfite (MBS) dosages were evaluated and the use of utilizing ozone and ultra violet (UV) light to oxidize cyanide was investigated. All the data was evaluated and mass balances were compiled to develop several flowsheets. Overall encouraging results were found using a combination of ozone and MBS.IntroductionAnaconda Mining Inc.’s Point Rousse project includes an operating gold processing plant located on the Baie Verte Peninsula in Newfoundland which is in the process of improving and expanding. This plant comprises of milling and flotation followed by cyanide leaching in order to extract the gold. The residue from cyanide leaching is filtered by drum filters prior to being clarified for the Merrill-Crowe process. Once the gold has been recovered by the Merrill-Crowe process the effluent is filtered by filter presses and the resulting filtrate as well as the solids from the drum filters are detoxified prior to being pumped to the tailings pond along with the flotation tailings.The entire process is very dependent upon the efficient destruction of cyanide in the effluents and successful tailings handling. Substantial amounts of effluent are delivered to tailings ponds after gold extraction which could create environmental problems if the regulations are not met. Environmental regulations stipulate that final effluents contain no more than 1 mg/L Total CN.The detoxified tailings of the Point Rousse project are produced by the INCO SO2-Air circuit depicted in Figure 1. These detox tailings contain 10 mg/L Total CN at that point of the circuit and this was selected as the target to be matched while reducing overall MBS consumption rates from 3.2 g/L per minute. Prior to detoxification, the filter press tailings contain 520 mg/L Total CN while the drum tailings contain 29 mg/L Total CN."

Jan 1, 2017

By J. Lee, M. Peart, T. Bhambhani, D. R. Nagaraj, P. Riccio

"Over the past decade or so, our efforts have focused on developing the rationale and concepts for new technology in reagent development and optimization in the processing of base and precious metals. A major outcome of these efforts have been the development of a novel family of collectors, principally driven by the MAXGOLD® and Aero XD-5002® chemistries, for precious metals recovery from primary Au ores and Cu-Au ores. These chemistries was developed to be robust to address the complex mineralogy and gold deportment in these ores. Plant trial data for a variety of ores have confirmed that the both Aero® XD-5002 and MAXGOLD® chemistry are indeed versatile in recovering gold values occurring as gold alloys and/or associated with many types of sulfides, and in altering the deportment of certain sulfides (such as those bearing As, Bi etc). An overview will be given in this paper using plant data to highlight the application of these reagents.INTRODUCTIONThe subject matter of this paper is the flotation of Au containing minerals from their ores. The motivation from this manuscript comes from the several challenges faced with the processing of Au ores, as was articulated in detail by Nagaraj (2008). The biggest challenge is the complex mineralogy; most easy-to-treat free-milling ores bodies are largely depleted. The Au values are distributed in multiple host minerals such as pyrite, pyrrhotite, arsenopyrite and Cu minerals such as chalcopyrite. Au values also happen to be finely disseminated within the various minerals and are sometimes invisible in optical microscopy. Additionally, on any given day, some mines treat multiple ore types, and the mineralogy is different for each ore type.Xanthates continue to be the collectors of choice at most Au and PGM operations around the world. Most primary Au operations tend to consume very large amounts of collectors; the dosage ranges anywhere between 40-400 g/t and this has been attributed to both mineralogical and non-mineralogical factors (non-mineralogical factors include the low cost of xanthates and the mindset that “more is always better”, which is not necessarily the case). In addition, several studies now show that xanthates alone are never sufficient where multiple value minerals are present, and that supplementary collectors are required. The large doses present a substantial cost to the minerals industry, and many mining companies have expressed the need for more efficient reagents that can improve metallurgical performance at low dosages."

Jan 1, 2013

By J. Miettunen

"The lining of a grinding mill has an important role in creating the conditions for the grinding process. The main purpose of the lining is to transfer the energy taken by the mill motor to the contents of a mill. The power draw curve of the mill, if measured with sufficiently short intervals, describes how well the lining works in lifting and mixing the material to be ground.The power draw curve can also be used for determining the volumetric filling of a mill. This new measuring technique was developed at the Pyhasalmi concentrator in 1989-90. The measuring device with its PC-connections offers an excellent tool for controlling volumetric mill filling, for maximizing throughput and for research purpose (e.g. process studies, mill linings design).The paper describes the new method and the results achieved at Outokumpu's concentrators.INTRODUCTIONVarious methods have been developed for measuring mill load; weighing, noise, etc. Weighing is one of the most reliable methods but installing the sensor to existing mills is often difficult. Besides the load measurement does not indicate the volumetric filling if the specific gravity of the mill feed fluctuates. Noise measurement has often failed with its sensitivity to various disturbance sources.As known, the power draw measurement is one of the most accurate measurements in grinding circuits and therefore it has been utilized in sophisticated control, e.g. in power peak seeking algorithms for maintaining maximum grinding efficiency.About 10 years ago power oscillation measurement was developed at Pyhasalmi concentrator. In this method the amplitude of the oscillation caused by the lifters was measured. The oscillation amplitude and the mill filling has quite a good correlation and together with the power draw measurement it could be used for maximizing mill throughput (Koivistoinen and Miettunen, 1989). The main difficulties in this method were that the dependence between mill filling and the amplitude is unlinear and that the dependence also is individual for each mill.The method developed during 1989-90 is also based on the power oscillation but on its phase shift. In principle level of the material in a mill is measured. The method has been successfully used for maximizing throughput at Pyhasalmi and Enonkoski concentrators and at Harjavalta slag concentrator."

Jan 1, 1991

By B. Stimpson, K. Kosar, K. Barron

"A number of high wall failures have occurred in some of the Alberta coal strip mines of a type called by the authors ""Multiple block plane shear slope failure "". They cause rapid deterioration of the dragline bench, reduced productivity and maintenance costs.The failures are invariably associated with the presence of almost horizontal (± 5 degrees) bentonitic clay bands in the overburden, often immediately above the coal seam, and regress behind the slope as a series of tension cracks which isolate detached blocks. As many as 17 sets of cracks have been observed, at lateral distances in excess of five times the slope height from the toe.The theory of this mode of failure is presented and a limiting equilibrium computer program which will produce deterministic or probabilistic (Monte Carlo) solutions is briefly described. A case history of one such failure is documented. It is shown that the extent of the regressive failure is exceedingly sensitive to the water table elevation, leading to the conclusion that drainage, if practical, represents the best control strategy. IntroductionA number of high wall slope failures are occurring in some of the coal strip mines in Alberta of a type called by the authors ""Multiple block plane shear slope failure""(I). These failures cause a rapid deterioration of the bench from which the dragline operates, reduced productivity, and necessitate conregresses into the slope as a series of tension cracks and detached blocks. As many as 17 prominent cracks or crack zones have been observed, the last being in excess of five times the slope height distant from the toe.The block between each pair of cracks must be at limiting equilibrium, i.e. the factor of safety equals one. This condition can be used to determine the locations of the cracks which develop in sequence behind the face."

Jan 1, 1986

By Fathi Habashi

"Crushing and grinding of ores and their beneficiation by washing away gangue minerals has been practiced since ancient times. Primitive crushing was done by hand pounding the ore with a hard stone then by using metallic hammers. The mortar and pestle was mechanized using a lever and when the size of operations increased in the middle ages, the stamp mill was introduced. The grindstone played an important role in grinding of ores. Panning for gold and hand sorting of minerals were two old methods of separation, now gave way to modern techniques. Flotation started in the middle of the nineteenth century by using oils to collect the mineral particles and float them on the surface of the aqueous slurry. It was only in the 1920s when it was discovered that organic compounds were affective floating agents. Textbooks written by distinguished engineers such as Rittinger, Rickard, Pryor, Taggart, Richards, Gaudin, and others contributed to the recognition of this field as a new discipline to be taught in Universities. INTRODUCTIONThe ancient Egyptians knew already that it would be easier to melt an earth rich in gold particles than another which is poor. As a result all efforts were made to enrich the gold by washing away the light gangue minerals (Figure 1). Another ancient method for enriching gold particles from a river stream was by means of fleece, hence the Greek myth of the “golden fleece”. The present day Georgia was known in ancient times as Colchis and was a center for gold working. It was known to the ancient Greek as the land of Golden Fleece. The use of special cloth to catch gold particles was also described by Agricola in his 1555 book De Re Metallica (Figure 2)."

Jan 1, 2009

By Norman O. Lotter, Dominic Fragomeni, Lori J. Kormos, Guy Comeau, Antonio Di Feo

"A performance opportunity was identified for the Raglan concentrator operation by changing the selection of xanthate from Potassium Amyl Xanthate (PAX) to Potassium Isobutyl Xanthate (PIBX). This opportunity was identified by a Statistical Benchmark Survey of the operation and QEMSCAN measurement of these survey samples, in which fine liberated pentlandite was found in the final tailings. This was confirmed by some laboratory scale flotation testwork using High- Confidence Flotation Testing. A statistically designed plant trial was implemented in 2007 to measure and confirm the performance gain. This trial design used on-off switching following a three-month reference distribution of normal operations using PAX. This layout provided both external and internal reference distributions on PAX to be established. These were used to evaluate the internal reference distributions on PIBX. This trial format was deliberately designed so as to block out the effects of autocorrelation in the operations data. In this way, small but significant metal recovery gains may be measured and proven in a plant trial. The paper describes the case study to show that this approach successfully blocks out autocorrelation in time, which is an obstacle in analysing concentrator operations data. The results showed that the PIBX had produced clear and statistically significant recovery gains for Ni, Cu, Pt and Pd. Adjusted for feed and concentrate grades, these recovery gains were: Ni: 1.00, Cu: 0.96, Pt: 5.07 and Pd: 1.90%.INTRODUCTIONConcentrator OperationsMilling and flotation, sometimes accompanied by gravity separation, are well-established unit processes. These have traditionally been used to treat ore that has been mined, producing a lowbulk concentrate containing a high percentage of the paymetal(s) in the ore mined. These concentrates are more economically treated in subsequent beneficiation processes than the ore from which they were produced.This choice of a concentration process results in a significant and variable paymetal loss to the concentrator tailing. This tailing is discarded and disposed of in an impoundment area, and has no immediate business use. This paymetal loss forms the largest loss of paymetal in the entire flowsheet by which refined, or saleable, metal(s) are produced [Cramer, 2001]. The question arises as to whether any particular concentrator is performing at its full potential, and how this answer may be determined. In a concentrator operation, there is always an ongoing performance improvement programme for this reason."

Jan 1, 2009

By D. Wolfe, K. Reid, T. Nunn

"The Aurora North mine has been operating for more than ten years, and is the source of over half of Syncrude’s bitumen production. In order to minimize front-end rejects, and to allow for high throughput, the ore top size at Aurora has been set at a nominal 125 mm. These relatively large lumps have a significant effect on both pump performance and pipeline pressure gradient. Current design methods underestimate the solids de-rating effect of lumpy slurries in pumps, and do not accurately describe the distribution or magnitude of the lump effect on pipeline pressure gradient. Data from the Aurora hydrotransport systems has been compiled, to quantify the effect of lumps on the pump head ratio and pipeline pressure gradient, and how this effect changes as lump ablation occurs along the length of the pipeline. A model has been built, using a logarithmic curve, which predicts the effect of 125 mm lumps on pipeline pressure gradient as a function of velocity and the distance from the start of a hydrotransport pipeline. This model is applicable only to Aurora hydrotransport operation, but similar models could be developed for other operations using the same methods. Using accurate pipeline pressure gradients and pump head ratios when designing future hydrotransport pipeline systems will help improve their reliability and operability."

Jan 1, 2014

By S. Mostaghel, V. Hernandez, S. Ge

"The automotive industry is under a constant pressure to reduce the weight of vehicles in order to reduce emissions and improve fuel efficiency. As such, there is an ever-growing demand for high strength and high ductility steel grades to meet the need for lightweight automotive components. Over the past decade, the production and application of 2nd and 3rd generation Advanced High Strength Steels (AHSS) as a lightweight material in automobiles has gained significant popularity due to their exceptional mechanical properties. However, the production cost of these high manganese steel remains high, partially due to the need of large amounts of ferromanganese as alloying material in standard steelmaking processes.The current study introduces a new and cost-effective technology for the production of medium- and high-manganese steels, where self-fluxed micro-pellets of manganese ore will be used as the source of manganese that can be injected into the steel bath. Prior to injection, these pellets are subjected to a pre-reduction process using a mixture of H2 and CO gases, where partial metallization of iron and manganese will occur. Direct injection of the pre-reduced micro-pellets provides less volatilization/emission and higher recovery of manganese, and is capable of producing AHSS with 6–18 wt% Mn.INTRODUCTIONAutomakers are constantly searching for lighter, stronger and cheaper materials in an effort to create safer and more fuel efficient vehicles. The introduction of aluminum alloys and polymer composite materials for automotive applications has been carving into what is traditionally one of the most profitable markets of the iron and steel business. The steel industry responded with Advanced High Strength Steel (AHSS)—a family of manganese containing steels which exhibit exceptional strength and ductility."

Jan 1, 2016

By Ralph W. Edie

"IntroductionTHE GOLDFIELDS AREA in northern Saskatchewan has be-come important in recent years because of numerous discoveries of pitchblende. The area is underlain by rocks of Precambrian age and, because of metamorphism and hydrothermal alteration, the geology in the vicinity of the pitchblende deposits is exceedingly complex and presents a challenge to all geologists •working in the district. This paper is a contribution to the geological literature of the area and presents a description of rock types, supplemented with petrographic, chemical, and spectrochemical data.Field work in connection with this paper was carried out during the summers of 1948, 1949, and 1950 while the writer was employed as assistant geologist for the Crown Corporation, Eldorado Mining and Refining ( 1944), Limited, Gold-fields area. Laboratory work was undertaken at the Massachusetts Institute of Technology during the winter months of 1949-50 and 1950-51 and extended through the summer of 1951.With the exception of SiO2and FeO, all of the new analyses ( 1) presented were carried out by quantitative spectrographic techniques under the supervision of Dr. L. H. Ahrens at M.I.T. Many of the techniques have only recently been developed at that Institute and detailed laboratory procedures have not yet been published."

Jan 1, 1952

By Emmanuel Henry

Few industries are more challenged by technical, political and market uncertainty than the mineral industry. Technical uncertainty in mining projects concerns the volume and quality of the resource, the processing and metallurgical parameters, the production efficiency, etc. Political uncertainty can take diverse forms and includes possibilities of change in the taxation system, risk of expropriation and risk of social instability or war. Market uncertainty depends on the market structure of the commodity; price and demand volatilities are the most common sources of market uncertainty. Intensive feasibility studies including these uncertainties and risks are required before investing up to billions of dollars in the development of a new mine. Current feasibility studies are often based on a single (or very few) mean geological scenario and simplified price profiles along the life of the project. Yet, strategic decisions, for example, the level of investment in exploration and metallurgical studies, adoption of a flexible, but more costly, mine design and risk-sharing strategies are made at an early stage. Over the last twenty years, Real Option theory has emerged as a unifying framework enabling strategic planning under uncertainty (technical, political and market). Geological and market variances (second order statistics) are pivotal for proper uncertainty quantification. The present study explores the possible benefits of combining modern geostatistical tools and financial techniques for project management. More precisely, the following questions are examined: Is geological uncertainty really an issue? Can we combine geological and price uncertainties in a unifying Real Option framework? A simple example aimed at illustrating the concepts involved is presented.

May 1, 2003

Westwood Quebec Long Life, Low Cost CONSTRUCTION UPDATE ? Shaft advanced to 840m (after 1 year), 3 km of down ramp and 2 km of exploration drift ? Head frame and hoist room structure completed ? 2009, 84,700m drilling program completed (increase 9%) 2010 OUTLOOK ? $102 million expenditures planned ? Shaft to advance to 1,300m and the first loading excavate 71,500m drilling program planned

May 1, 2010