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By R. K. Borden

Rio Tinto is committed to proactive mineral waste and acid rock drainage management. Corporate requirements are closely aligned with the GARD Guide principles of early geochemical characterization and prediction followed by selection and implementation of management strategies to prevent or minimize ARD. Each operation is required to design and implement an ARD and Mineral Waste Management Plan. Successful implementation of the plan requires commitment at all levels of the company, from senior management, to geologists, mine planners, environmental staff and equipment operators. Examples of the successful integration of ARD management strategies into mine operations are cited from several mines.

Jan 1, 2011

By Mike Johnson, Niels Verbaan, David Dreisinger

The Search Minerals Foxtrot project in Labrador represents a significant Canadian resource of rare earth elements rich in the sought after heavy rare earth elements (19.8% HREE/TREE). A preliminary economic assessment of the project indicated that the project is technically feasible and economically attractive. A variety of metallurgical test programs have been undertaken which have led to significant streamlining and simplification of the process flowsheet. The improved flowsheet should allow Search to reach production earlier and will use conventional processing equipment. The results of these test programs are presented and discussed in this paper.

Jan 1, 2014

By K. G. Wheeland, J. E. Dutrizac, M. Wasserlauf, A. A. Condy

Numerous processes for the treatment of thiosalts in base metal milling effluents have been examined in the past decade. Flowsheets for thirteen processes are outlined, and cost estimates are presented for a base case of a 720 mi/h effluent flow containing 1400 mg/L thiosalts. The processes are ranked on the basis of Numerous processes for the treatment of thiosalts in base metal milling effluents have been examined in the past decade. Flowsheets for thirteen processes are outlined, and cost estimates are presented for a base case of a 720 mi/h effluent flow containing 1400 mg/L thiosalts. The processes are ranked on the basis of

Jan 1, 1988

By Zhibao Li, Kunming Zhai, Yan Zhang

The hydration kinetics of MgO, namely magnesia or magnesium oxide, obtained by calcination of magnesite MgCO3 or synthetic MgCO3·3H2O has been studied. Nesquehonite (MgCO3·3H2O) was prepared by the reaction of MgCl2 with Na2CO3 in a mixed-suspension mixed-product removal (MSMPR) crystallizer at 40 °C. Three magnesium oxide samples were obtained by calcination of magnesite MgCO3 or synthetic MgCO3·3H2O in muffle furnace at 900, 1100 and 1300 °C for 3 h, respectively. The hydration experiments of MgO samples were investigated at 25, 35 and 45 °C for 24 h in a stirred batch reactor. The hydration results indicate that the rate and extent of hydration of magnesia decreased remarkably with hydration temperature and increased with decreasing calcination temperature at a constant hydration temperature. The whole hydration reaction of magnesia was supposed to experience the promotive period and declining period. An empirical kinetic model ( k t p -?ln(1-??) ??) and a modification of the classical shrinking core model for diffusion control ( k t b d -?-?3 2 ????1 [1 (1 ??) ] ) have been applied to fit the experimental data of hydration in two stages, respectively. The values of kinetic parameters ( p k and d k ) were obtained by regression analysis and the activation energy of the sample at 900 °C was estimated to be 34.23 kJ/mol. The comparison between MgO from calcination of synthetic MgCO3·3H2O and a commercial MgO used in silicon steel production was carried out, indicating that special silicon steel grade MgO can be obtained by calcination of MgCO3·3H2O below 900 °C.

Jan 1, 2014

By L. C. Lien

Tower crane layout (TCL) is a typical construction site layout (CSL) problem, which is suitable for a wide range of work assignments and site conditions. Tower crane is one of the key facilities for vertical and horizontal transportation of materials, especially for heavy prefabrication units such as steel beams, ready mixed concrete, prefabricated elements and large panel formwork such as machinery and equipment, and a wide variety of other building materials within a construction site. However, it is a difficult combinatorial optimization problem to determine the locations of tower cranes with materials quantity supply and demand for engineers. Swarm intelligence (SI) was very popular and widely used in many complex optimization problems which was collective behaviour of social systems such as honey bees (bee algorithm, BA) and birds (particle swarm optimization, PSO). This study applied a hybrid swarm algorithm namely particle bee algorithm (PBA) based on a particular intelligent behaviour of honey bee and bird swarms by integrates theirs advantages. This study compares the performance of PBA with BA and PSO for a proposed hypothetical construction engineering of TCL with materials quantity supply and demand problem. Results show that PBA performs better performance than the mentioned algorithms on a proposed hypothetical TCL problem.

Aug 1, 2013

By S. Banisi, E. Arghavani, A. Akbari, Gh. A. Parsapour, S. Darvish Tafvizi

The new copper processing plant of the Sarcheshmeh copper complex consists of two parallel circuits. After a primary crushing, the ore is sent to a SAG mill and the product is further ground in a ball mill. The overflow of the hydrocyclones is fed to a flotation circuit which contains 8 rougher tank cells (RCS130), 3 cleaner cells (RCS50), 5 scavenger cells (RCS50) and a 4 x 12 m flotation column as recleaner. The circuit was initially designed to process a feed containing 0.8% Cu, but because of the ore type change, the feed grade decreased to 0.6% Cu. This resulted in a reduction of final concentrate grade and recovery from 28 and 85.5% to 24 and 84.4%, respectively. Based on the original design, the copper and silica recovery in the cleaner cells should be 69 and 55%, respectively, but these values increased to 85 and 75% because of a higher retention time. The rather high silica recovery (i.e., 75%) was found to be the main source of the lower final concentrate grade. In order to reduce the retention time of particles in the cleaner cell from 13.7 to 6.9 min, the rougher concentrates of two parallel circuits were fed to only one cleaner-scavenger and regrind circuit. This modification increased the cleaner and final concentrate grade from 15.1 and 24.5% to 17 and 26%, respectively. To prevent a possible reduction in the copper recovery, the froth depth in the scavenger cells was reduced. The overall outcome of the circuit modification was evaluated to be a 10% reduction in the energy consumption without any loss in the overall copper recovery.

Jan 1, 2016

By Deborah A. McCombe

"There are a number of important dates that must be disclosed when a Qualified Person (QP) is preparing a technical report for securities purposes. The dates are discussed in NI43-101 and the Form of the Technical Report, NI43-101F1. •,Effective date of the technical report •,Possible revision date of the report •,Effective date of mineral resources and mineral reserves •,Date of the personal inspection (site visit) •,Signature date of the date report (execution date) •,Date of the certificate of the QP •,Date of the consent of the QP The effective date of the report is basically the cut-off date for the information that is included in the technical report. The effective date should be close to the signature date. If there is too long a period between these dates, the QP runs the risk of new material information becoming available and then the technical report would no longer be current. The effective date is disclosed on the title page of the report and on the signature page. If a technical report needs to be revised to correct problems or disclosure deficiencies identified by the regulators, the QP will normally need to include a revision date on the title page of the report to distinguish the revised version from the original version. In these circumstances, the regulators will request that the original date of the report remain on the title page and the revised date will be below it. When a technical report must be revised, the QP must resign and date the signature page of the report and provide a new certificate and consent."

Jan 1, 2003

By Paul W. Shelley, Daniel J. Hodges

The mining industry is undergoing a period of rapid transformative change.  This is the result of the social and financial accountabilities that the industry is faced with because of the world’s desire to cap average temperature increase to 1.50C above pre-industrial levels (UNFCC, 2016).  To limit global warming to 1.50C, greenhouse gas emissions must peak before 2025 at the latest and decline 43% by 2030.  In hard rock mining, comminution is identified as the major energy consumer, being responsible for 40-60% of the electricity use.  It follows that comminution is the major greenhouse gas emission process of the mine.  All effort is being made to radically reduce the carbon emissions of comminution. Grinding media plays a large role in the energy consumption and carbon emission story.  In recent years industry practitioners have attempted to quantify the grinding media carbon footprint.  This paper makes a definitive contribution to that discussion.  The grinding media carbon footprint is quantified in Scope 1, 2 and 3 emission terms in the context of a grinding media supplier.  Major emission contributors, steel, natural gas and electricity are discussed in detail.  The steel industry transition is a key factor. The paper will explore the steel industry transition and its effect on grinding media manufacturing.  The carbon footprint of heritage steel process routes are analysed and compared with the process routes of the future.  Emerging steel making technologies are presented and discussed.  The future of the steel manufacturing and procurement route for grinding media is proposed. This narrative allows for a comparison between the heritage carbon footprint and the future carbon footprint of manufactured grinding media.  Of equal importance is the opportunity of reducing the grinding media carbon footprint in the field.  The paper explores possibilities of reducing the grinding media carbon footprint at the customer site.  Media in use options are presented that take account of the mineral characteristics, the mill dynamics, and the product metallurgy to optimise both carbon footprint and media performance. It is intended that this is a landmark paper in the discussion of the carbon footprint of grinding media.

May 4, 2025

By W. Dingley, G. R. Hoey

"Thirteen Canadian sulphide ore mines were surveyed for corrosion control. The mines visited were a small, yet representative, proportion of this segment of the Canadian mining and metallurgical industry. Information on metallic corrosion and methods used to control it in underground workings and mills was gathered (a) by discussing corrosion problems with company personnel, (b) by examining equipment and structures during under-ground and mill tours, (c) by photographing corrosion sites, and (d) by collecting and analyzing mine water samples.The corrosion survey, which is summarized in the re-port, leads to the following general conclusions. Mine environments are corrosive, particularly when the mine w1a-ter is acidic. Because of a lack of good corrosion control measures, excessive deterioration of equipment due to corrosion occurs in mines. Mill environments are also corrosive, but in some cases good preventive measures are being taken to effectively control corrosion losses.Ways to reduce corrosion losses in sulphide ore mines and mills are discussed. The main areas for more corrosion research and development are selection of materials of construction, protective coatings, cathodic protection, inhibitors, equipment design, and mining and milling practices."

Jan 1, 1971

By Phil A. Keele

"IntroductionGeneralThe Genesee Coal Mine is a joint venture of Fording Coal Limited and the city of Edmonton. The mine supplies thermal coal to the Genesee Generating Station operated by Edmonton Power and is located approximately 75 km southwest of Edmonton (Fig. I).Under the terms of the joint venture agreement, Fording Coal Limited has designed and developed the Genesee Coal Mine. Fording also operates the mine which has a minimum economic life of thirty-five years. Mine development started in the spring of 1987 with the construction of the dragline erection pad and mine service complex. Major development of mining areas was carried out in 1988 with the construction of haul roads, powerlines, topsoil recovery, etc. Mining officially commenced on December 14,1988.The mine produces 1.6 million tonnes of coal per year and employs 65 people. MiningGround conditions have turned out to be very poor, as expected with the majority of the overburden in the first few years a soft lacustrine clay with minor amounts of fine-grained glacial till. To compound matters, what was expected to be a relatively uniform coal subcrop turned out to be a very irregular erosional contact.The coal mined at Genesee is a sub-bituminous Class B thermal coal with approximately 16070 ash, 21% moisture, 8300 Btu/lb and 0.27% sulphur on an as-mined basis.The primary piece of mining equipment used at the Genesee Coal Mine is a M8200 walking dragline. It has an effective operating radius of 100.6 m, a 50.5 m3 bucket, and weighs approximately 3860 tonnes yielding a ground pressure of III KN/m2•Figure 2 illustrates schematically the single pass mining sequence presently employed at the Genesee Coal Mine. The M8200 is used to lift all coal out of the cut, the coal being placed in stockpiles on the prepared pad .This method maximizes coal recovery under the conditions where spoil failures due to poor material would otherwise put men and equipment at risk. The coal is subsequently loaded by the coal shovel operating on the same bench as the M8200 dragline and delivered to the plant as required.All mined areas, as required under Alberta Legislation, are to be returned to an agricultural land capability equal to or better than that which existed prior to mining. Reclamation activities, as a result, are an important and integral part of the mining process. A complete list of the primary mining equipment deployed at the Genesee Operations appears in Table I."

Jan 1, 1994

By K Belanger, J. Mclachlan, F. Stober, G. Norval, B. Snider, A. Munsch, T. Koehler, E. Piantino, J. Carlos Queiroz

The project to rebuild the smelting furnaces at the Anglo American - Barro Alto ferronickel smelter, located in Goias, Brasil, was initiated in September 2013. To optimize the capital cost, while maximizing furnace integrity and robustness, a design basis giving flexibility to ore composition variation was developed in order to ensure sustained nameplate production. The resulting capital efficient, fasttracked project execution was accomplished through the creation of an integrated project team of Anglo American and Hatch through FEL 3 and FEL 4 phases of the project. The integrated team addressed the project challenges through a cooperative and versatile approach, created by access to knowledge, experience and systems in both Anglo American and Hatch. The team could operate at an optimized speed of execution, as demonstrated in the FEL 3 and FEL 4 completion durations, as well as efficiently mitigating any risks of increasing cost or delaying schedule by utilizing lessons learned and team knowledge from Anglo American on the original green-field project and Platinum smelters and Hatch on similar reference ferronickel furnace rebuilds. Other critical drivers of project cost minimization and revenue loss/generation (considering production revenue of each furnace) are scheduled durations for construction, commissioning and ramp-up. The integrated team commenced construction, commission and ramp-up planning almost one year in advance of the shutdown and this paper will discuss the strategies developed to reduce risks and optimize the construction schedule to mitigate revenue loss and optimize ramp-up time to sustained operation at nameplate capacity.

Jan 1, 2015

By Z. Jun, L. Kerning

Jinlong copper smelter and refinery, originally designed for 100,000tpa primary copper and started up in 1997, has been expanding its capacity on the basis of operational optimization and by modifying its facilities. Currently it is producing 210,000tpa primary copper, and the new phase of expansion project with a target capacity of 350,000tpa primary copper is ongoing. This paper reviews problems and improvements made with operation and equipment in the past years. Recent plant operation is briefly described. The expansion projects completed are summarized and the ongoing expansion project is present.

Jan 1, 2007

By P. -M. Tardif, S. Outalha, R. Le

"This paper proposes a new direction to implement an underground mine communication system. It presents actual underground communication systems and discusses their technological limits. A new system based on a wireless local area network (WLAN), together with its main systems characteristics, is then proposed. This paper also presents an experimental protocol for radio frequency propagation measurements. Finally, the paper describes the projected implementation of a WLAN in an experimental mine. IntroductionDuring the last decade, a number of Canadian mining companies have invested in modern communications systems in order to automate processes and reduce operational costs. Safety of miners is also a concern, regulated by health and safety regimes.Underground communication systems rely mainly on analog technology (especially the leaky feeder). Digital upgrades have been made to modernize this technology using a coaxial or fibre optic cable to transmit voice, documents, commands, controls, and video. Therefore, all wired equipment can benefit from an increase in efficiency from the digital technology.However, when it comes to mobile equipment, the only medium was, and is, still radio waves. With the advent of the wireless local area network (WLAN) standard, one can use a technology similar to that of the cellular phone to connect transparently different equipment. WLAN enables the transmission at rates higher than 2 M bits of voice, documents, commands, controls, identification, and of course, digital video. This technology was developed with inbuilding use in mind. Now, one can try to adapt it to underground mines."

Jan 1, 2000

By Nicole Peter

When introducing digital training technology a practical approach helps address cultural concerns.  Solutions to help create acceptance are discussed.  Resistance to change may be deeply rooted in traditional mine training personnel.  Traditional training staff members may consider themselves less digitally-savvy and resist technological methods available to them. A transitional approach intended to help mitigate or resolve resistance is presented as a continuous improvement pathway toward full adoption.  This presentation contends every mine should welcome the benefit of a digitally connected critical enabler.  The adoption of a digitally savvy learning centre is often viewed a disrupter to existing practice.  Given a commitment-driven learning centre model, technology offers the opportunity to transition from a compliance-based training model to one of competence.  Learning and Development practitioners should welcome the latest advances in neuroscience, Bloom’s taxonomy of learning model, and principles which guide mine safety training as outlined by the Lowell Institute for Mineral Resources at the University of Arizona. By employing digital applications to include animation, game-based simulations and immersive Virtual Reality (VR) these technologies create a viable digitally-savvy learning centre. We will outline the ingredients of a digitally enabled, or VR, Learning Centre to offer some observed benefits, successes, and potential short-comings. Much excitement in the industry surrounds implementation of simulation and/or VR headset training.  Given fair consideration of these as a ‘fit-for-purpose’ solution we examine the paradigm shift required to create real results for on-the-job learning.  Interim steps may be needed to meet the cultural transformation.   Simpler forms of VR, in the form of 3D models and VR environments as displayed on a large interactive touch screen, can serve to bridge this challenge and address a group learning environment. Features of the interactive 3D technology and ease of adoption are presented.  Usage of the touch screen is similar to that of a smart phone. It may be implemented as an obvious transitional tool.  To help describe merits of the interactive touch screen the presentation points out these sample underground and surface mine training applications. There are 3-D simulations such as ventilation, emergency response, support installation, and mine cycle and activity scheduling programs. These applications offer the ability to conduct entry examinations, complete digital pre-use checklists, and perform planned task observations in the virtual world of work. The tool may be used to teach the flow of hydraulics and do fault-finding on machinery such as loaders and dump trucks. Learners may navigate in a virtual mining environment to identify hazards, detect and assess abnormal ground conditions, address poor design features, and alleviate traffic constraints. It is possible to use connected physical controls to navigate machinery in the virtual environment. We conclude the presentation with a “compare and contrast” approach to cite potential cultural benefits by adopting a transitional method. 

May 4, 2025

By P. Kolodziejczyk

Mining seismicity can be harmful both under and on the surface. ? Tremors are not totally damaging, but destructive to buildings and infrastructure, especially in highly urbanized regions, such as Upper Silesia in Poland ? Destroy the social appreciation, trust and support for mining industry ? To prevent or reduce these effects, engineers and scientists develop methods allowing prediction of ground shaking intensity near buildings and various losses that can result from it Evaluation and prediction of mining tremor?s damaging influence on buildings is usually solved with two steps: ? Estimation of local ground shaking intensity (based on known attenuation relation) and classification into one of several predefined intensity intervals ? Apply supposed relation between the shaking intensity interval and qualitatively defined damaging effects to express predicted effects This makes a mixed quantitative/qualitative procedure, difficult to analyze or optimize

Aug 1, 2013

By R. H. O. Wagner

"This paper describes the bench testing, pilot plant studies of alternative flowsheets, to determine the feasibility of gold recovery, by carbon in pulp extraction, in the Schumacher Mill gold flotation tailings. The economics were calculated based on pilot plant recoveries and actual industry operating costs.The economics of the carbon in pulp treatment of the gold flotation tailings were not justifiable. The economics of desliming the gold flotation tailings followed by carbon in pulp treatment were marginal, but favourable. INTRODUCTIONPamour Porcupine Mines, Limited is a gold, silver and copper producer located in Timmins, Ontario. In 1983 the head grade of Pamour's gold ores averaged nine one hundredths of a troy ounce of gold per short ton.Pamour operates two area mills to concentrate the gold ores. Free milling gold ores are processed at the Pamour One Mine mill, whereas the refractory carbonaceous gold ores, and complex gold, silver, and copper sulphide ores, are processed through the Schumacher Mine mill.The complex Schumacher mill feed ores do not all react favourably to flotation methods, consequently this study was commissioned to investigate the feasibility of the carbon in pulp cyanidation of the Schumacher mill gold flotation tailings. These tailings contain ten to fifteen percent of the gold in the mill feed. During the study period, the average grade of the Schumacher mill flotation tailings was nine one thousandths of a troy ounce of gold per ton, or one quarter of a gram of gold per metric tonne."

Jan 1, 1984

By Ray Walton, Ron Colquhoun, Ken Thomas, Dwayne Fentie, Barney Burke

"The new Roasting Facility at Barrick’s Goldstrike Mine in Nevada, U.S.A. was developed to process 12,000 tons per day of refractory gold ore. The process consists of crushing, dry grinding, roasting, extensive gas purification, calcine quenching and leaching in the presence of activated carbon. The new plant is integrated into the existing Goldstrike facility, treating ore from both open pit and underground sources.The process design, procurement, construction and commissioning of the Roaster facility was performed successfully over a 3% year period with peaks of 400 engineering personnel and 950 construction personnel supporting the project. The US$330,000,000 project was completed ahead of schedule and under budget. The commissioning was well planned and proceeded smoothly through a rapid start-up to achieve all primary goals within three months of the start of processing of ore.BACKGROUNDAs early as 1992, Barrick’s Goldstrike Mine, located north of Carlin, Nevada had indications of the ore becoming ever increasingly carbonaceous in nature. As the open pit and underground exploration programs proceeded to step out over the years that followed, the accumulative amount of carbonaceous refractory ore and tons had become significant. By 1997, 29 million tons of double refractory carbonaceous ore containing an estimated 11.6 million ounces of gold had been identified. By 2000 the resource had increased to 14.3 million ounces."

Jan 1, 2001

By L. M. Lowe, D. G. Feasby, J. R. Goode

"Rare earth resources usually contain minor amounts of radioactive elements. The most widely recognised sources of radioactivity are associated with thorium and uranium. However, also present in the resources are isotopes of rare earth elements (REE) that are themselves radioactive, including lanthanum (La-138), lutetium (Lu-176) and samarium (Sm-147). These radioisotopes, as well as remnants of the natural thorium (Th-232) and uranium (U-238, U-235) decay series, can contribute to significant levels of radioactivity in mixed REE concentrates and in separated products. Levels such as these can present challenges for transport, transboundary movement, product storage, workers’ health and safety, as well as waste management issues at the facilities that separate out the individual REE’s. These are discussed in this paper. A particularly challenging radioactive isotope is Ac-227 (a decay product in the U-235 decay series). Actinium behaves chemically similar to lanthanides and hence normally concentrates with REE multi-element composites. Reliable analysis of Ac-227 is not widely available and the methodology required to deal with this challenge is briefly described. A principle reason for minimization of radioactive content throughout REE processing is restrictive specifications by concentrate purchasers in order to reduce waste management challenges. Approaches to the minimization of radioisotope content in REE concentrates and separated products are outlined in this paper."

Jan 1, 2014

By C. E. Baltzer

This paper highlights the position of coal supply in regard to the requirements for electric-utility operations. The text and the appended tables outline the trend of thermal power development and fuel use in the electric-utility industry. Mention is made of several argumentative factors influencing the use of coal in relation to competitive oil and gas, and of the importance attached to developing a realistic understanding of the respective problems faced by the supplier and consumer of coal. * * * TREND OF" THERMAL POWER DEVELOPMENT T HE RATE OF ADVANCE in thermal power has been significant during recent years, particularly in the Atlantic Provinces, the Prairie Provinces, Ontario, and British Columbia. While dependence on thermal power in Quebec and the Northern Territories is less than in the remainder of Canada, these regions also eventually will have need for increased amounts of such power.

Jan 1, 1961

By A. Philipp, A. S. Middleton, G. A. Harron, A. B. Durham

"Basal till sampling techniques were used to search for gold mineralization in the Timmins, Ontario area. During 1978 and 1979, approximately 90 overburden sampling drill holes were completed in Murphy and Hoyle Townships to test specific geophysically defined target areas. A conventional tricone dual tube drill system, and a unique retractable tricone/rock coring system were used to various advantages.First pass till sampling at 800 to 1200 ft intervals perpendicular to ice transport direction yielded anomalous gold values in till and carbonatized quartz pyrite-rich bedrock chips, and lateritic soil. Subsequent induced polarization-resistivity surveys defined the areal extent of a pyritic carbonate alteration zone. A second pass till sampling/limited rock coring program evaluated the gold mineralization potential of the alteration zone. Diamond drilling has substantiated the till and bedrock gold anomalies. Further evaluation of this mineralization is currently in progress. IntroductionThis paper describes an integrated geochemical/geophysical gold mineralization discovery case history in Hoyle Township. This discovery is on a property jointly owned (I983) by Canamax Resources Inc. and Du Pont of Canada Exploration Limited. Exploration of the property began in 1978 by Rosario Resources Canada Ltd. and in 1979 a joint venture agreement was signed with Du Pont of Canada Exploration Limited. Rosario Resources Canada Ltd. was taken over by Amax Minerals Exploration in 1981, which became Canamax Resources Inc. in 1982.The work described in this paper deals with a gold mineralization discovery located three-quarters of a mile northwest of the gold deposit currently being readied for underground exploration and development. Further drilling is required to investigate the economic potential of the gold mineralization herein described."

Jan 1, 1987