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The original JKMRC AG/SAG mill model was developed over 30 years ago and has been upgraded a number of times since then, with the current published version being the Variable Rates model that is now over 15 years old. Since this model was developed further enhancements have been derived, some of which are applied in-house and some which have yet to be incorporated. The published and the commercially available model in JKSimMet is currently undergoing a comprehensive overhaul with a vastly extended data base for model evolution and validation. Improvements developed within the AMIRA P9 project, in-house development and a number of collaborative projects, are being incorporated into the upgraded model structure. Enhanced capabilities will include: power-based breakage rates scaling; a far wider mill filling range (from 10% to 40%) that exhibits peak in throughput as mill filling increases; higher ball loads; improved pebble discharge function; improved slurry discharge function incorporating important mill design and operational influences; and the new size dependent breakage function. The model will also be able to accommodate some influence of liner design and multi-component ores (blends of hard and soft components). This upgrade is still a work in progress but substantial changes have been made to date. This paper presents some of the new improvements and their influence on the predictive capability of the model.

Jan 1, 2012

By H. Hamza

Efficient and effective management of extraction process tailings is an essential ingredient for the continued success and development of Alberta's vast oil sands resources. Open-pit oil sands operations north of Fort McMurray recover bitumen from flotation circuits. Process tailings are managed in carefully engineered and monitored external tailings management facilities and in below-grade mine pits. In order to support reduction of production costs and improve upon established tailings management practices, CANMET has been working with the oil sands industry in a collaborative framework to assess the potential to integrate thickened tailings into oil sands extraction process flowsheets. Albian Sands has commercialized the process while others, including Syncrude Canada Ltd., continue to evaluate the suitability of the process for their operations. This paper provides an update on R&D work undertaken in recent years to assess and develop the potential of thickened tailings technology for the open-pit oil sands operators of northern Alberta. The aim of this work was to explore opportunities to optimize process efficiency and environmental sustainability by improving water and energy conservation and develop more alternatives for tailings management and reclamation.

Jan 1, 2004

By Marcio Luis S. Godoy

The Salobo Project will be the first Vale operation to use an HPGR mill to process copper-gold ore. The mine is located in Para state, southeast of the Amazon region in Brazil. The circuit was designed to treat 12 million metric tons per year of finely disseminated sulphide ore with high hardness. The comminution circuit comprises a gyratory primary crusher, secondary crushing utilizing two cone crushers, two 2 x 1.5 m HPGR operating in closed configuration with 6 mm screens, followed by two 26 x 40 ft ball mills. The concentration circuit consists of two rougher flotation stages using mechanical cells, regrinding with vertical mills, three cleaner stages with columns and one cleaner scavenger stage in mechanical cells. The concentrate is dewatered, filtered and transported by trucks and train to the port, to be exported. The circuit was designed on the basis of data obtained from a comprehensive laboratory and pilot plant campaign. The ore variability was assessed through simulation using data from a drilling core characterization program. The start-up of the industrial plant is planned for 2011. This paper describes the main aspects of circuit design, as well as information related to the beginning of the project construction.

May 1, 2010

By F. H. Samuel, P. Burke, F. Mucciardi, J. Gruzleski, S. A. Musmar

A new thermal analysis technique has been developed and tested. It utilizes the enhancement in heat transfer characteristics associated with a recent advancement in heat pipe technology. Heat is extracted from a liquid sample of a melt taken in-situ within a vessel or furnace. The rate of heat extraction is such as to cause the sample to solidify. The technique was tested in both laboratory scale and industrial scale (Grenville Castings, Perth, Ontario). A 356 Al Alloy, subjected to various melt treatments was used to perform the tests. Classical thermal analysis was also performed simultaneously using a preheated graphite cup and at the same melt conditions. The comparison showed the potential of the new technique over classical thermal analysis. The major advantages of the new method are that it conducts the analysis inside the melt (i.e. a physical sample is not removed from the melt), it consumes less time and the cooling rate can be precisely controlled during the solidification process. Moreover, the resolution of the results is better than that of conventional techniques. Aluminium

Jan 1, 2006

By S. Yadav, T. G. Murthy, C. Saldana

"An experimental study has been carried out in order to study the deformation of porous brittle materials under plane strain indentation. Gypsum, which is well known model system for understanding the behaviour of soft rocks, is used in this study. The effect of wedge angle is investigated in this research through this series of experiments, using wedges of 3 different apical angles. High-speed, high-resolution images are captured using a CMOS camera during the experiment. The images obtained are analyzed using a Particle Image Velocimetry (PIV) algorithm in order to obtain the evolving velocity, strain-rate and strain fields.INTRODUCTIONThe problem of indentation, which is usually referred to in the context of hardness testing is ubiquitous as a material characterization technique for a large class of solids. Mechanical properties of materials such as yield stress, flow stress, fracture toughness, elastic moduli etc. can be related to the hardness of a given solid. The indentation problem involves a given material or solid (whose properties are to be determined) indented by a relatively harder material (indenter) allowing the solid to undergo plastic deformation, which is then related to the yield stress of the material. The problem of indentation and its variants see many applications ranging from mining and petroleum industry, infrastructure industry, manufacturing, and biomedical sectors. Indentation has been extensively studied in metals, with accurate measurement of deformation parameters, stresses and comparison with analytical solutions. On the other hand, understanding of indentation in other class of solids such as cellular solids, porous solids, rocks, and soft solids is still nascent. In case of rocks, a comprehensive understanding of the indentation problem is very crucial because of the obvious applications in mining, petroleum and infrastructure sectors. The inherent porosity, the brittle nature of the rocks, adds to the complexity of indentation in these porous brittle solids. Various theoretical models with degrees of simplifying assumptions have been proposed to study the indentation in rocks. The most common model used in the study of indentation in rocks is a cavity expansion model, wherein a blunt indenter indenting into a rock is approximated with the expansion of cylindrical or spherical cavity in an elastic-plastic material. Complementary studies in understanding fracture initiation and propagation due to indentation has been largely based on the studies of traditional brittle materials such as glass."

Jan 1, 2015

By D. Runnels, Daniel Roy, Ricardo Esteban, J. Torrealba-Vargas

"An intuitive way to reduce power consumption in grinding operations is to feed the grinding circuit with finer feed by enhancing blasting and fragmentation control. The optimization of blasting with the objective of minimizing power consumption in grinding is not new.The study was based on a Canadian mine that processes a very hard ore. BBA conducted blasting/fragmentation and grinding circuit surveys in 2014. The results of the exercise were used to develop a base case model to simulate the effect of blasting in the operation on the grinding circuit. Tools for fragmentation simulations, particle size measurement and crushing/grinding simulations were used with the objective of reducing the OPEX costs including power consumption.The paper describes the steps involved in the model optimization as well as an economical evaluation of the OPEX savings.INTRODUCTIONIn 2014 BBA was retained by one of its clients to conduct a crushing and grinding survey. The objective of the survey was to update the grinding circuit model with production data and also to develop a tool to investigate opportunities for process improvement.A second phase of the study involved the development of drilling and blasting and crushing models. The models were used to diagnose the operations and to investigate opportunities for process improvement.The objective of the present study is to describe the approach and to identify potential improvements to overall mine site operating costs by better integrating mining and milling operating costs with blasting and grinding models."

Jan 1, 2016

By K. A. Hildebrant, J. R. Norgate

"Synthetic lubricants have for many years documented extended service life and provided superior performance in temperature extremes. Increasing interest in synthetics' ability to reduce energy costs has resulted in laboratory and industry application evaluations. These tests have documented savings in functions such as worm gear drives, spur gears and in compressors. Energy savings data are presented as well as payback calculations as low as thirty days.The National Research Council of Canada has estimated that the Canadian economy loses over five billion dollars per year in friction and wear. Figures quoted were for 1986 during which it was estimated that nine hundred and forty million dollars were lost in the mining industry alone"" It has been further estimated that about 115 million dollars can be immediately recovered through improved tribology practices (Table I).The purpose of this paper is to present results and savings opportunities through the use of synthetic lubricants in various but common applications. Many other areas exist with the opportunity for energy savings such as in the use of more efficient drive equipment, reduced contact seals, spray mist lubrication systems and reduced friction coatings on rotating equipment such as pump impellers"

Jan 1, 1994

By Jeff Smith

Agenda About NORTHPARKES The NEED The INITIATIVE The SEARCH The PRODUCTS The SOLUTION The RESULTS The Northparkes copper-gold mine in Central Western NSW commenced operations in 1994. Copper concentrate is produced and shipped to smelters in Japan, China & India under long term contracts with spot sales to other Asian countries.

May 1, 2006

By K. Sakai, M. Miyaue, T. Aoki, T. Tani, S. Tanaka, N. Kudo

In the planning stage of a tunnel, due to limited technology in the geological survey and the financial restriction, tunnel supports are often designed from unsatisfactory information, and the tunnel construction is started. Therefore, "Information-oriented construction" is carried out in the construction stage, in which the design is rationally verified and modified by observations/measurements. Moreover, the ground conditions ahead of a tunnel face must be predicted for efficient and safe tunnel construction. The authors have examined effective prediction methods to the ground conditions ahead of a tunnel face under construction of mountain tunnels (Aoki et al., 2010) in view of the established method (Schubert et al., 1995). Though the prediction method of Schubert requires the displacement in the direction of tunnel axis, it is difficult to obtain its accurate data by the electronic distance meter. Then, we have proposed a method that uses tilt sensors installed at the tunnel crown near the face to obtain the slight tilting information. To measure inclination of the tunnel crown, this inclinometer was originally developed as a daily control measurement, such that the geological condition and its possible change behind the face could be detected early, and a steady advance and construction safety could be ensured. This paper describes the method of forward prediction mechanism and advantages of this suggested method. It then presents the typical results of a field verification test at a tunnel under construction and an example of evaluation of the ground conditions ahead of the face based on the 3D numerical analysis in three types of condition changes of ground deformation moduli.

Jan 1, 2015

By Robert B. Parsons

"Effective January 1, 1990, mines in British Columbia are subject to a new provincial mining tax statute, the Mineral Tax Act. Under this Act, mines are subject to a two-tier tax system, with a minimum tax payable on ""net current proceeds"" and a higher tax paid on net income. For many mines, the present value of tax paid under the new rules should be comparable to the amount paid under the old rules. Earlier cash payments could pose difficulties, particularly for smaller mines, but existing producing mines could benefit in the short-term.IntroductionEffective January 1, 1990, British Columbia has replaced the provincial mining tax regime under the Mineral Resources Tax Act with a new system under the Mineral Tax Act. The new rules borrow some ideas from other provinces (New Brunswick's two-tier concept, and Saskatchewan's indexed costs) with a view to levying a tax that is fairer to both the producer and the province."

Jan 1, 1990

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 R. Dawes, B. R. Davis, T. LeBel, C. Pelow

Settling of copper, lead, and other metals in slags is an important part of overall recovery of metals, both in primary and secondary operations. The impact of slag reduction on settling is not well known. This is important since the cycle time for slag cleaning can be significantly changed with reduction of slag, through a decrease in slag viscosity and growth of metal/sulphide particles. KPM has worked with a number of primary and secondary recyclers to better understand how reduction of slag can improve overall operation. In this presentation, we describe the type of test work and analysis done and how this information can be used to guide improvements in metal recovery from slags. INTRODUCTION Typically, copper smelter slags contain about 1-2% copper, both in the form of copper and copper sulphide beads and dissolved copper oxide in the slag (converter slags are recycled to the smelter). With the average grade of world copper deposits close to 0.7%, it is practical to recovery copper from these slags. This is done routinely by one of two methods. The first method uses slow cooling in large ladles or beds to grow particles of copper sulphide. The slag is then crushed, milled, and floated for copper recovery. The slow cooling promotes precipitation and growing of the sulphide particles from the solution and then, the slag can then be milled to recover the copper through froth flotation. A consideration of this process includes the energy cost related to grinding, the use of water, capital cost for ladles, and the availability of tailing dumps. At the same time, the retreatment of the Cu concentrate produced in the mill will displace fresh concentrate, which ultimately results in a reduction of the throughput. The second method is the so-called “slag cleaning” and is based on the settling of copper and copper sulphides particles dispersed in the slag. This is achieved by decreasing its viscosity by increasing the slag temperature and reducing the iron spinel solid phases (magnetite) that increase the apparent viscosity of the slag. Typically, the reduction does not extend to the reduction of copper, and soluble copper (mainly as oxide) and fine matte particles remain at concentrations typically at or above 0.5% (Cardona et al., 2011; Cardona, 2011). This is an improvement on 20 years ago when slag was sent to dumps at 1% or less (Demetrio et al., 2000).

Jan 1, 2019

By S. Pietruszczak, G. Su, T. S. Nguyen, E. Haghighat

"In this paper, the mechanical properties of Tournemire argillite are modeled using a mathematical framework which employs the microstructure tensor approach (Pietruszczak & Mroz, 2000). The experimental data incorporates the results of a series of triaxial tests (Abdi & Evgin, 2013) conducted at different orientation of bedding planes relative to the direction of loading. First, a plasticity framework is presented which involves the specification of the conditions at failure as well as the description of the irreversible deformation process. Later, a systematic procedure is outlined for identification of material functions/parameters involved. The paper is concluded by presenting the results of numerical simulations of the triaxial tests. It is demonstrated that the model can adequately reproduce the primary effects of anisotropy in the stable deformation regime as well as the onset of fracture.INTRODUCTIONThe understanding of the mechanical behaviour of argillaceous rocks is important in many types of geotechnical projects, including petroleum extraction, carbon dioxide sequestration as well as deep geological disposal of radioactive waste. In all these cases, the primary concern is the onset and propagation of damage due to excavation, transport of pore fluids and/or elevated temperature. The Canadian Nuclear Safety Commission (CNSC), Canada’s nuclear regulator, will be responsible for the licensing of future deep geological repositories. In order to evaluate the safety of deep geological repositories, CNSC staff keep abreast of scientific developments by collaborating with national and international partners on experimental and theoretical research on the long-term performance of those engineered and natural barriers. Through that collaboration, the CNSC has access to data resulting from experiments performed at different Underground Research Laboratories (URL). Such an URL is situated in Tournemire, France, in an argillaceous rock formation, the Tournemire argillite. The Tournemire argillite is characterized by the presence of closely spaced bedding planes and exhibits a strong anisotropic behaviour, so that its strength as well as deformation properties are directionally dependent."

Jan 1, 2015

By Robert B. Parsons

"In all likelihood, Canada's mining industry would be adversely affected by corporate tax reform proposals actively being considered by the Department of Finance in Ottawa. When the next set of proposals for lax reform is released later this year as promised by Finance, the mining industry had better be prepared 10 take a hard look.IntroductionTwo federal budgets ago, in May 1985, Finance Minister Wilson tabled budget papers that were more massive in terms of volume than most federal budgets. Buried in this mass of documentation is a discussion paper entitled ""The Corporate Income Tax System-A Direction For Change"". When the discussion paper was tabled over one year ago, reaction from the business sector was almost nonexistent. By and large, the paper was regarded as nothing more than one more federal publication of mild academic interest.But, recent events suggest that this discussion paper for corporate tax reform could be the cornerstone for a series of changes to the tax laws which would have more profound and widespread effects for all sectors of the economy than any reform since 1971 . No industry in Canada can afford to ignore the movement afoot in Ottawa for corporate tax reform."

Jan 1, 1986

By G. R. Baiden

This paper discusses the application of Load-Haul-Dump (LHD) machine teleoperation in combination with a guidance system for single operator control of multiple IJIDs. A system accomplishing these goals has been tested at Copper Cliff North Mine of Inco Limited. This development uses a high-speed, high-capacity production network to teleoperate an LHD during loading and dumping by using 3D video and radio remote control. Following loading, the operator dispatches the LHD using an automatic guidance system to traverse the drifts to the orepass. Remote dumping is done at the ore pass and then the machine returns to repeat the procedure. This has significant productivity gains and improvements in safety. Productivity is improved because operators are involved only in the loading and dumping part of the process. This frees the operators to utilize their time more effectively, loading or dumping a particular machine, while other machines with guidance systems continue to work travelling and/or automatically dumping ore in the ore passes. Safety is improved as the operator is located on a remote control station. Automatic dumping will be incorporated as a future development.

Jan 1, 1994

By E. Haccuria

Due to the growing share of electrical cars, the use of lithium ion batteries significantly increased. Recycling of these batteries is essential to safely dispose hazardous materials as well as to recover valuables (Cu, Ni, Co, etc.). In order to optimise the recycling process, accurate information is required on the slag phase equilibria for battery smelting. The slag is a multi-component system containing alumina from the battery cases, silica and lime from fluxes, and manganese and lithium from the electrode materials. The present study accurately determined the phase equilibria in the "MnO"-Al2O3-SiO2 sub-ternary system at metal alloy saturation. Particular attention was given to the accuracy and reliability of the final results by highlighting the different reaction pathways, mass transfer- and reaction mechanisms taking place in the system during experiments. This attention enabled improved experimental methodology and measurements. Based on the present study, further measurements will be undertaken in the quaternary "MnO"-Al2O3-CaO-SiO2 system at low "MnO" concentrations, which closely represents the future recycling industrial slags.

Jan 1, 2014

By E. M. De Souza, P. Lausch, D. O. DeGagné, J. F. Archibald

"The potential use of industrial and municipal waste glass as a partial pozzolanic replacement for Normal Portland cement in mine backfill has been investigated. Considerable quantities of glass are currently discarded into landfill sites at high cost to municipal and industrial users with no foreseeable environmental benefits being gained by such disposal. This research study was undertaken to assess the viability of using ground waste glass materials as partial binder replacement of Portland cement fractionswithin consolidated mine backfill materials. The program was implemented to review various factors that could influence successful incorporation of glass waste replacement of cement, these factors being the feasibility of glass waste procurement, determination of process economics and the physical and chemical suitability of ground waste glass materials to generate adequate backfill strength when replacing Normal Portland cement fractions. A series of laboratory assessment trials were established to evaluate backfill component characteristics and mixture strength properties for both standard Portland cement-consolidated and blended Portland cement/ground waste glass-consolidated backfill materials. Side-by-side review of the strength behaviour of various component backfill/cement mixtures was designed to permit comparative evaluation of the capabilities of ground waste glass and Portland cement products as backfill consolidating agents"

Jan 1, 1995

By Marke Wong

? Vietnam?s economy is growing so fast that gross domestic product (GDP) growth remained above 8% in 2005 and exports are rising steadily at 25% per year. ? Demand for electricity is expected to increase 18% per year through 2010 requiring an additional estimated 7,547 MW before 2010 ? Domestic coal demand is expected to be over 45 Mt by 2010. ? The Quang Ninhcoal deposits are estimated at 6.5-7 billion tons (350m) Vietnam News Agency. Saturday, May, 6, 2006. ? National resources are now estimated at 10 billion tonnes; not including a relative new coal bed discovery estimated at 210 billion tonnesin the Red River Basin.

May 1, 2006

Terrane?s Canadian Assets Mt. Milligan, British Columbia Copper, gold (100%) Berg, British Columbia Copper, molybdenum (100%) Howards Pass, Yukon/NWT border Zinc (Option payments, and Royalty interest) Maze Lake, Nunavut Gold (Joint venture with Laurentian Gold Fields)

May 1, 2010

By Avinash Kandalam, Markus Reuter, Jörg Kleeberg, Michael Stelter

The Top Submerged Lance (TSL) technology has obtained significant importance in the pyrometallurgy industry for nearly four decades. One of the advantages of TSL furnace is its high reaction rate, which is caused by splashing and turbulence of the melt. In contradiction, this phenomenon stands as a barrier for conducting experimental investigations to validate the simulation models. The highly turbulent and splashing environment in the TSL furnace is caused due to the immersion of the lance into the slag layer and thus the effect of the flame structure is directly related to the splashing, turbulence, reaction kinetics and life-span of the lance. Moreover, the material properties such as viscosity, density and the surface tension will also influence the flame structure. As a first step to understand the flame structure, attempts are made to generate a stable flame of the lance in an open environment. INTRODUCTION Top Submerged Lance (TSL) technology was invented during the 1970s at Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia by Floyd and Denholm. This technology was later commercialised and currently, there are about 100 TSL plants around the world commissioned by various licence holders such as AUSMELT (Outotec) and ISASMELT (Xstrata- Glencore Technology). Copper is the most produced non-ferrous metal followed by lead and zinc, see Hunt (2005). Today, a wide range of primary, secondary, and complex recycling materials are used as a feed material in the TSL, Alvear et al. (2010), Kaye et al. (2008). The working principle of TSL technology lies on inserting and submerging a lance from the top of a vertical cylindrical chamber into the slag layer. The lance is considered as the heart of the furnace, where the air and fuel are transported through two concentric tubes and are mixed in a combustion chamber, which is approximately 7 cm from the tip of the lance (considering the pilot-scale TSL furnace at the Institute for Nonferrous Metallurgy and Purest Materials - INEMET). The TSL furnace is very flexible with the type of fuel, feed material and the air input. The fuel can be natural gas/heating oil/fine coal particles and the air could be enriched with oxygen (Figure 1). The general mechanism of the TSL furnace lies on feeding the material from the top of the furnace and the material is pulled into the molten bath due to the high turbulent atmosphere, which results in high reaction rates. The thermocouples installed in the furnace (i.e. in the ceramic linings) allow the operator to know the temperature of the melt. For example, in the case of copper production the tapped material (i.e. matte/metal) can be transported to a settler for further processing or directly used.

Jan 1, 2019