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By Steve W. Ciccone

The Red Dog Mine is both the largest known zinc reserve and the largest zinc producer in the world. The mine started in 1989, and by 1999 had increased production from approximately 300,000 tonnes per year (t/yr) of zinc concentrate to in excess of 900,000 t/yr. The VIP Mill Optimization Project further increased zinc concentrate production to 1.1M t/yr while improving both product quality and zinc recovery. The Mill Optimization project also addressed a number of issues related to risk reduction: power generation capacity, water treatment capacity and concentrate thickening. The project was faced with numerous challenges, the most daunting of which was the schedule. This US$105M project was executed, from conception to completion, inside of two years. Less than nine months elapsed from concept to delivery of materials and equipment to site. The project also faced a 100-day icefree shipping window, the challenges of construction in an Arctic environment, and an extremely tight labour market for qualified craft personnel. These challenges were successfully addressed with several innovative approaches to project execution, including an Alliance contracting arrangement between the owner, engineer and contractor; full integration of the team; construction of modules in Anchorage; and fast-track engineering, procurement and construction. Steve Ciccone, AMEC?s project manager on the Mill Optimization project, works for the Mining & Metals unit of AMEC, a world leader in the provision of engineering and construction services. He obtained his BASc from the University of British Columbia and is currently midway through his MBA program at Simon Fraser University. Steve has 15 years of experience providing engineering and project management services on mining and metals projects, and has been involved in the execution of five capital projects and several studies at Red Dog since 1995. George Hope was responsible for process design and engineering on the Mill Optimization project and has been Manager, Project Development at Teck Cominco since 1995. Prior to this time, he was a project manager and chief metallurgist for Lac Minerals for 14 years and a mill superintendent and metallurgist for Noranda for 5 years. George received his BSc in Mineral Technology from the Royal School of Mines in England.

May 1, 2002

By P. Cleyle, K. McDermott, M. Hall, C. A. Harris

"This paper describes the implementation of an expert system for monitoring and control of the NO. 4 autogeneous mill and spiral circuits at Wabush Mines.This process control system incorporated the mill operating expertize of Wabush Mines operating personnel and was implemented to improve spiral iron recovery and mill productivity by:1. Continuously monitoring the mill power draw and ensuring that the mill feedrate is regulated to prevent damage to the mill motor, while simultaneously maintaining the feedrate at or as close as possible to the maximum feedrate determined by the process supervisor.2. Improving control over the spiral density and feed rate.3. Improving control over both tbe rougher and cleaner wash water.4. Reducing the frequency with which pumps are plugged.5. Allowing modifications to be made easily and quickly to test various operating strategies.This system was installed using COMDALE/C, a real-time Expert System for Process Control. It was readily accepted by the process operators and produces higher production performance in comparison to the other 5 parallel mill lines at a lower power draw."

Jan 1, 1992

By P. Bousquet

Acid mine drainage (AMD) is a serious environmental problem that preoccupies the Canadian mining industry. Considerable amounts of money are spent every year in an effort to prevent or reduce the acid mine drainage phenomenon. AMD occurs when sulphide minerals (e.g., pyrite) contained in rock are exposed to air and water and subsequently oxidize to produce low pH water. This acid effluent has the potential to mobilize any heavy metals contained in the rock. Coating the sulphide minerals with silicates is a new promising technology to reduce AMD. Pyrite is treated with a solution containing H2O2, sodium silicate and a buffering agent. H2O2 oxidizes a small part of pyrite producing ferric iron (Fe3+) ions. These ions subsequently react with the silicate ions to produce ferric hydroxide-silica that precipitates on the pyrite surface producing a passive coating. This silicate coating can protect the grains of pyrite from oxidation. This paper presents a series of experiments that confirm that silicate coating can considerably reduce AMD.

Jan 1, 2002

By Natasha A. Essar

Nevsun Resources Ltd. Bisha Mine Project is a gold and base metal development project in the Gash Barka region of west-central Eritrea. The project has the potential to be one of the largest industrial developments in the country, and Eritreans have no experience in modern mining. Nevsun recognized early that the success of the Bisha Project would require meaningful consultation and engagement with all levels of Eritrean society. Meaningful engagement required not only full disclosure, but also capacity building from government officials at all levels to other stakeholders who live in the nearby communities. This paper describes the approach used to develop capacity and to help introduce a modern mining culture in a country without previous experience in mining.

May 1, 2007

"The most widely used method for predicting the onset of continuous caving is Laubscher’s caving chart. A detailed examination of this method was undertaken which concluded that it had limitations which may impact on results, particularly when dealing with stronger rock masses that are outside current experience. These limitations relate to inadequate guidelines for adjustment factors to rock mass rating (RMR), concerns about the position on the chart of critical case history data, undocumented changes to the method and an inadequate number of data points to be confident of stability boundaries.A review was undertaken on the application and reliability of a numerical method of assessing cavability. The review highlighted a number of issues, which at this stage, make numerical continuum methods problematic for predicting cavability. This is in particular reference to sensitivity to input parameters that are difficult to determine accurately and mesh dependency.An extended version of the Mathews method for open stope design was developed as an alternative method of predicting the onset of continuous caving. A number of caving case histories were collected and analyzed and a caving boundary delineated statistically on the Mathews stability graph. The definition of the caving boundary was aided by the existence of a large and wide-ranging stability database from non-caving mines. A caving rate model was extrapolated from the extended Mathews stability graph but could only be partially validated due to a lack of reliable data."

Jan 1, 2003

By J. Ran

"Hangingwall sloughing is the major cause of unplanned stope dilution in open stope mining. Understanding the hangingwall sloughing mechanism can guide the stope design in minimizing the unplanned dilution and improving muck size and therefore mining efficiency. Though the modified stability graph method may be adopted to assess the hangingwall stability, for mines where the hangingwall is inaccessible, the required parameters are difficult to define and some of the simple influential factors cannot be easily identified in this method to provide guidelines for stope design.This paper identifies the main modes of hangingwall sloughing in open stope mining based on detailed data collected from mined-out stopes and site observations, applies the voussoir beam notation to analysis of the hangingwall sloughing mechanism, compares the model analysis results with the collected stope data, and provides guidelines for stope design and model application. Finally, examples are given to demonstrate the time and support effects on hangingwall sloughing and stope dilution."

Jan 1, 2002

By R. J. Johnston

"INTRODUCTIONPoint Mines is located about 65 miles east of Hay River on the South Shore of the Great Slave Lake. It is connected to the Northern Alberta Railway System by the Great Slave Lake Division of CN Railways at Roma Junction, Alberta.The operation started in the fall of 1965 with a capacity of 5000 t.p.d. An addition was put into operation late in 1968 to bring the capacity up to 8000 t.p.d. The present milling rate is 11,000 t.p.d.The location of Pine Point Mines is such that long end cold winters are to be expected end temperatures of lower than -200F are encountered from late October to late March, with extended periods of -300F being common in January and February.It was recognized by Cominco engineers during the initial design period that since freezing would be encountered with open pit ore somewhere in the crushing circuit, the problem was to reduce it as much as possible. Other mines, working under similar conditions, found that the fine ore bins feeding the grinding circuit were the main problem area. The decision was reached, therefore, to have heated fine ore bins and to make sure thst the ore was sufficiently warm to prevent freezing.CRUSHING PLANT FLOWSHEETThe crushing plant has a standard open flow circuit (flowsheet). Ore from the stockpile is loaded into R-50 Euclid trucks by Caterpillar 992 Front End Loader with 11 cu. yd. bucket and dumped into a 42 x 65 C.A.C. Superior Crusher driven by a 300 HP motor. The crusher is set at a nominal 5 inches. The ore falls through into a 100-ton surge bin. There are high level and low level nuclear gauges to allow the primary operator to optimize for optimum orientation."

Jan 1, 1972

By T. Nyabeze

This paper presents the experiences and views of women involved in the mining industry as determined from a questionnaire that was circulated across the Canadian mining industry. Globally, there have been significant studies done to understand the historic and global variety of women?s participation in this industry1. The reason for focusing on women?s experiences here in Canada is because women?s percentage representation at 14.4% in the mineral industry workforce falls below the overall labour force average of 47.4%2. Notably, a recent article in the Globe and Mail newspaper points out that adequate representation of women in leading of organizations is more of a matter of competitiveness and innovation rather than purely a ?women?s issue?3. This paper will provide some insight into the reasons why women join and stay in the mining industry and shed some light into the reasons for the overall low representation in this sector. The authors believe, as stated in a study from the London Business School, that a gender-balanced workforce is one way of providing the best results in areas that drive innovation4. Women represent a key stakeholder group that can help enhance the mining industry?s sustainability through innovation. The women who responded to the questionnaire represent many different areas within the mining industry, including a broad range of roles in industry, government, academia and in the supplies and services sector. The paper is intended to raise awareness about issues that women encounter that contribute or detract from career satisfaction in the mining industry. The survey provides an overall understanding of why women pursue or work in mining, and why women either remain or choose to leave it. The advantages and disadvantages experienced by women are highlighted, along with a summary of the possible initiatives that could be undertaken by employers as opportunities to improve the attraction of the mining industry for career minded women. As well, the survey provides a summary of the top ten features that are already in place at various organizations and community groups that have been identified as key for supporting and encouraging women to join and remain in the industry. Not surprisingly, the survey identifies that one of the key ingredients for retention of women in mining is the provision of mentors and sponsors. Another key aspect for retention is the provision of progressive employment policies that address the need for a degree of flexibility in work hours and a culture of balance between work and personal life demands. The survey and results are portrayed only from a female perspective since it is largely women?s perceptions that will inevitably be transmitted to others who plan on entering the field.

Oct 1, 2010

By Glenn D. Lyle

As part of an initiative to improve value in mining, CEMI is developing a handbook on best practice in mine design. Various formats were examined, and of these, the wiki was selected as being most suitable. Being web-based, its global reach and capability of being continuously updated allows the wiki to evolve as new knowledge is generated, and to capture the diversity of experience of practitioners in the mining industry. While wikis have many advantages in terms of organizing content and searching, their ability to be edited by users is often seen as a negative characteristic for quality control. To ensure reliability of information content, author attribution, specific authorship models, and a peer review process have been implemented, in addition to the standard version tracking capability of wikis. The first phase of the project concentrates on topics related to underground hard rock mine design. The scope will be expanded to cover other aspects of mining as the project matures. Strategic partnerships with various organizations, such as the CIM, and CANMET, are being formed to provide a wide range of seed material to stimulate growth of the site. www.minedesignwiki.org

May 1, 2011

By Nancy E. Wilk

In 2015, more than 1.2 million deaths annually were estimated to be caused by occupational risks (WHO, 2018). In 2021, this estimate increased with the publishing of the World Health Organization (WHO) and the International Labour Office (ILO) Joint Estimates of the Work-related Burden of Disease and Injury based on data from 2000 to 2016 (WHO/ILO, 2021). These global estimates reported that each year 1.9 million people die from exposure to occupational risk factors, 81% of these fatalities resulting from non-communicable, occupational diseases. WHO/ILO notes that the health-related risk factors with the largest number of attributable deaths were exposures to long working hours followed by workplace exposures to particulate matter, gases, and fumes. The health outcome with the greatest work-related burden of deaths was chronic obstructive pulmonary disease, followed by stroke and ischaemic heart disease. In considering the 2021 data published by WHO/ILO, it is likely that the estimates are low and underestimate the true burden of occupational disease and injury. In support of that position, more recently the ILO estimated that “2.3 million women and men around the world succumb to work-related accidents or diseases every year; this corresponds to over 6000 deaths every single day” (ILO, 2022).

Jan 1, 2023

By N. C. Clarke, T. Wu, M. le Page, K. J. Henley

In 1994, Gold Mines of Australia acquired the rights to the historic Mt. Lyell copper mine, and commenced a feasibility study into expanding production. The ore was shown in laboratory tests to be amenable to single-stage, fully autogenous grinding (FAG) of underground primary crushed ore, and this route offered the maximum cost savings. Flotation performance was expected to be enhanced. However, batch flotation tests done on pilot-scale autogenously ground ore showed an unexplainable recovery loss of between 1% and 3% Cu. A second pilot plant trial was set up, with the ground product feeding banks of continuous flotation cells. Single-stage FAG, FAG/pebble and FAG/ball circuits were tested. Results confirmed a loss of about 3% recovery with single-stage FAG milling. The FAG/ball circuit eliminated the loss. Analyses showed that autogenous milling probably produced more chalcopyrite/pyrite composites and that recovery of these composites was lower than with ball milling. In size fractions below about 53 microns, where chalcopyrite is well liberated, copper recovery was less affected by milling method and flotation selectivity. It was concluded that for the Mt. Lyell situation, a FAG/ball circuit was preferable to single-stage FAG.

Jan 1, 2002

By C. -K. Fang

"Aging effect on the wear resistance of alumina particulate-reinforced 6061 aluminum matrix composites with a block-on-ring wear tester has been investigated. Specimens with various Al2O3 volume fractions of 0%, 10% and 20% were employed in this work. Experimental results indicated that over-aged monolithic 6061 Al had the best wear resistance, as compared with under-aged and peak-aged conditions. For the composite containing 10% Al2O3, over-aging and peak-aging resulted in similar wear resistance, which was higher than that for underaging conditions. For the composite containing a high volume fraction (20%) of Al2O3, the wear resistance reduced with the increase in aging time. Although longer aging time was favourable to the wear resistance of monolithic 6061 Al, it was detrimental to that for the Al2O3/6061 Al composite with high volume fraction of particles. IntroductionMetal-matrix composites (MMCs) have received attention in many engineering applications because of the demands for high specific strength (strength-to-weight ratio) and specific stiffness, good high temperature capabilities and wear resistance. The manufacturing processes of fiber-, whisker-, and particulate-reinforced MMCs have been well developed (Hosking et al., 1982). Because of the reduction in fabrication cost, the applications of MMCs have been widely extended to light weight-bearing sleeves, calipers, automobile parts (brake rotors, drive shafts, connecting rods, piston rings, and cylinder liners), sporting goods, aerospace components, tanks (wheels, speed brakes, and track shoes) and other industrial applications. Among the three types of metal matrix composites, particulate-reinforced MMCs are promising because of their homogeneous and isotropic material properties and low cost. Additionally, they can be formed using conventional metal processing techniques."

Jan 1, 2003

By M. L. Joy

The heat pipe is a self-contained, passive structure that uses a liquid-vapour fluid cycle to provide high thermal conductance . Through the proper selection of working fluids and container materials, heat pipes have been operated at temperatures ranging from less than -300°F to more than 3,000 °F. The passive nature, high efficiency and configuration flexibility of the heat pipe are presented. The application of McDonnell Douglas Astronautics Company Cryo-Anchor® heat pipes for foundation and support stabilization in permafrost regions is discussed. Using the proven Cryo-Anchor technology base. a proposed application of heat pipes in a cold -region mine ventilation system heat recovery heat exchanger is presented. Information obtained from the development of an air-cooled heat pipe steam condenser provides the technical basis for large -scale heat pipe applications.

Jan 1, 1978

Once applied, EarthZyme reduces the tendency for a road to exhibit common maintenance issues: wash-boarding, rutting, heaving, potholing and dust.

Aug 1, 2013

By M. G. Lipsett

"The Mining Information Technology User Group considers information to be a strategic enabler to improved business performance in mining. This ad hoc group has been meeting since 2000 to share knowledge and leverage their efforts in effectively using IT in mining. In this paper, core issues to mining IT are reviewed, along with initiatives to engage industry professionals and decision-makers in the potential for improved use of information in their operations. Relevance of IT to Canadian MiningMining operations always drive to improve their performance, and so far they have succeeded by using different technologies. While economies of scale have come in fragmentation and material handling, and energy usage has improved through conservation and design of integrated mineral processing plants, these systems have the net result of tightening operational constraints, through reduced excess capacity. There are higher opportunity costs of lost production when integrated, large-scale systems are operating in a sub-optimal way.The problem is that it is profoundly difficult to run a mine in an optimal way. Optimization requires a defined objective function (e.g., profit), which is hard to pose, let alone solve, because so many inter-related aspects of an operation affect the bottom line. Even for a small, well-defined process state, it is difficult to measure all the pertinent information with sufficient accuracy to ensure that the system is performing well in real time.The art of mining remains making good decisions with uncertainty: in the orebody delineation; in the allocation of resources; in the efficiency of the operation; in the reliability of components and systems; and in responding to the downstream market. As well, individual decision-makers need to know how their decisions affect other processes and systems, so that improvements in one part of an operation do not result in such degraded performance in the rest of the plant that overall profitability goes down."

Jan 1, 2003

By C. Siac

"It is a widely held view that in the 21st century, the mining industry will be dominated by a relatively small number of large companies, truly global in scope and internationally staffed (Gooding, 1997). Interestingly enough, most of the exploration and exploitation activities are being carried out by junior and major mining companies from common law jurisdictions in civil law countries, in particular in Latin America, where in recent years, the region has ranked first as a destination for exploration dollars, thanks to the reforms undertaken by some countries to amend their legal framework to attract foreign investment. From a lawyer’s point of view, this is where the main challenge lies: how to bridge the gap between the two legal systems.In order to avoid pitfalls, common law lawyers should be more diligent and proactive when dealing with civil law jurisdictions, given the different systems of law, standards, traditions and customs. Common law lawyers cannot be expected to be well-versed in civil law but they should not be completely unfamiliar with it either. A balance should be struck to ensure clients’ needs are professionally taken care of and that common law requirements and standards are met."

Jan 1, 2003

By C. Vanvoren

"Since 1975, the Aluminium Pechiney Research Centre at Saint-Jean-de-Maurienne (LRF) has been concentrating its efforts on designing, testing and perfecting the Aluminium Pechiney point-fed prebaked reduction cell.In 1979, the AP18 cell (180 kA) was industrially launched with the construction and start-up of the F line in Saint-Jean. The following generation, the AP30 (300 kA), with prototypes started in 1981, was launched in 1986 on the Saint-Jean G line. Along with cell design, efficient process control systems were developed to pilot alumina feeding and bath composition. Together, these pots are currently producing 4.6 Mt of aluminum, i.e., 18% of the world’s overall yearly production.In 1989, the research centre faced a new challenge: to push the limits for the size of a reduction cell to further improve the profitability of Greenfield projects. This new generation development was also the opportunity for a significant redesign of the Aluminium Pechiney electrolysis information system.With a track record of ten years of semiindustrial operation with three prototypes, the AP50 technology is now ready for industrial implementation and enables a significant breakthrough to be made in terms of return on investment of a Greenfield smelter."

Jan 1, 2002

By D. P. Tripathy

A supply chain encompasses all the activities associated with the flow and transformation of goods from the raw materials stage(extraction), through to the end user. Supply chain management (SCM) is the integration of these activities through improved supply chain relationship, to achieve a sustainable competitive advantage and it rests on its ability to provide the right goods and services when and where needed. The supply chain is the vital component of any company?s value chain which links the operating processes to its supplier and customer. The globalization of business promises to offer new and unique challenges for the supply chain competencies of most firms. Challenges will also increase in the environmental aspects of supply chain often referred to as ?Green Issues?. The supply chain of mining industry comprises of the flow of material and information from the mine site, to processing and loading for transport, to the customer. However, due to recent changing environmental requirements affecting mining and mineral processing operations, increasing attention is given to developing environmental management (EM) strategies for the mineral supply chain. This paper focuses on: ? Environmental factors leading to the development of an extended environmental supply chain, ? Additional challenges presented by the extension, ? Performance measures appropriate for the extended supply chain, ? Developing a general procedure towards achieving and maintaining the green supply chain.

May 1, 2006

By Y. Guglielmi, C. Gout, P. Henry, P. Dick, C. Nussbaum

For a decade, observations and experiments conducted in underground environments worldwide (mines, underground research laboratories - URL) made it possible to bridge the scale gap between laboratory scale and large scale faults. Indeed, underground rock laboratories allow developing decameter scale relatively well constrained experiments at the smallest distance from the hypocenters. URL’s experiments allowed developing new monitoring technologies coupling pressure-strain-seismic measurements and reproducing complete earthquakes sequences analogous to natural ones. They also allowed exploring past movements of faults and sometimes also paleofluids in three dimensions and characterizing different fault architectures and hydromechanical properties in unaltered conditions. This is particularly important in the study of faults affecting clay formations which could not be observed at the Earth’s surface because of the high alteration. Here we show how examples from the Mont Terri (Switzerland) and Tournemire (France) The URLs may help in (i) defining the concepts of fault architecture in shales, (ii) estimating fault hydromechanical properties from field decameter scale experiments. Some key results are that faults which are critically stressed or at the rupture limit can reactivate for stresses variations within the range of those produced by shallow underground excavations, and that slight micrometer-to-millimeter scale reactivations may lead to large factor-of-10-to-1000 permeability increases. Such promising results show that URL’s experiments may bring new insights on some key processes that control the relations between fault stability and permeability evolutions in very permeable layers.

Jan 1, 2015

By Will Callupe Arzapalo

The success of the minimization of blast induced-damage at Barrick?s Pierina Mine in Peru is the result of an effective working relationship between Mine Operations and the Geotechnical Services Department. A detailed design criteria manual is used to match the blast plan to the site?s varying rock types and slope designs. The Geotechnical Services Department has further developed a comprehensive pre- and post-blast checklist that is critical to the drilling and blasting process as it pertains to wall stability. Wall control blasts are evaluated with quality assurance field checks, vibration monitoring and frequency control, video assisted performance quantification and post excavation face profiling. These detailed observations are compiled and summarized in a blast performance evaluation that is considered to be an ?Industry Best Practice?. The information and detail provided by each performance summary allows accurate blast analysis and effective design refinement.

May 1, 2006