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By M. Doggett

All 231 Canadian primary gold mines that produced from 1946 to 2004 were analyzed with respect to their production and economic characteristics. Trend analysis revealed that the average annual capacity of Canadian gold mines, as measured by ore processed or gold produced, has increased over time. Conversely, the average grade of gold mines has decreased over time. The distribution of gold output is highly uneven: for example, the 22 giant mines producing more than 100 t (metric tonnes) of gold account for 62% of total output. Small mines producing less than 10 t Au account for 54% of total mines, but less than 4% of total gold. Each historical mine in the database was evaluated on the basis of a set of economic and technical assumptions to determine if it would be economic to develop today. Based on the net present value using an 8% discount rate, only 103 of the 231 mines were determined to be economic. About 80% of the uneconomic mines had less than 10 t of contained gold, and 63% had less than 5 t. It is concluded that these small mines would not be viable today due to a combination of real capital cost increases, and more stringent permitting and environmental regulations. The implication is that future gold supply in Canada will hinge on the discovery and development of a new generation of larger mines. Given that only one giant mine has been discovered in the past 20 years, it seems likely that gold output will decrease in the future.

Jan 1, 2007

By O. Matwijenko

"1. IntroductionThe Falconbridge Owl Creek open pit gold mine is located 17 km northeast of Timmins and 2.5 km west of the Kidd Creek metallurgical site. Diamond drilling first commenced in 1964 with open pit production commencing in 1982. Other operations within close proximity are the Canamax-Pamour Bell Creek Mine and the Falconbridge Hoyle Pond Mine.Since 1982, 1,216,000 tonnes assaying 4.5 g/t have been processed in six concentrators. This paper summarizes the metallurgy achieved with special emphasis on some of the unique problems encountered in the processing of this refractory ore.2. GeologyThe Owl Creek deposit, located 3 km north of the Porcupine-Destor fault is in easterly trending carbonaceously altered volcanic and sedimentary rocks. The deposit strikes east and dips steeply north.The ore body can be best described as a wedge shaped sandwich of volcanic basalt between the surrounding sedimentary greywacke. The north and south volcanic-sedimentary interfaces are marked by graphitic zones. The south graphitic contact is more continuous with its thickness varying from 5 m to 20 m as compared to 0.5 m to 3 m to the north. Quartz veins occur throughout the deposit with a predominant vein running along the south contact where it is characterized by numerous graphitic inclusions. Some veins carrying gold values intrude into the sediments in the north. With depth the sedimentary and volcanic zones taper while the quartz-graphitic zones appear to become more dominant."

Jan 1, 1988

By G. M. Ritcey

The recovery of copper from low-grade solutions res ulting from dump leaching is well known, whereas the recovery from highly concentrated copper solutions has not been practiced. This paper discusses the use of Ashland Chemical's Kelex 100, a substituted quinoline, for the recovery of copper from solutions resulting from leaching copper-nickel concentrates. A flow sheet is described, and an economic comparison shows Kelex 100 to be superior to either the LIX 64N or LIX 70 reagents of General Mills for the recovery of copper.

Jan 1, 1973

By K. Bullock, M. Levesque, G. Lyle, D. L. Millar

ABSTRACT The options for reducing the carbon footprint of energy use in mining fall into three categories of activity: i) reducing demand, ii) improving energy utilization, and iii) adopting low carbon energy technologies. In addition to the environmental imperative, the economic case for these activities gains higher priority as the prices of electricity, gas, and liquid fuels increase. Low-carbon, energy-saving technology options that are available to mining industry companies lead to projects with return rates that must compete alongside other capital-intensive projects considered by mining company boards. Energy projects frequently involve longer payback periods and lower rates of return than those of competing bids for capital, such as new mineral property developments. For energy services companies that specialize in the financing, construction, efficient operation, and maintenance of energy projects, the same returns and payback periods can be considered acceptable or even attractive.

Jan 1, 2012

By D. Royston

In SAG mills fed with a variety of ore types, hard packing between the shell lifters can come and go depending on rock type and rock size distribution and the presence of a binder. Packing can appear in all sizes of SAG mills, and can be tenacious. High ball impact forces (depending on ball size) in larger mills may compact and encourage packing. Packing can have a negative impact on milling performance and a change in shell liner design may be required to remove it. However shell liner design changes need to be managed with care to ensure liner reliability. In smaller mills control of packing can extend shell plate wear-life and may help to maintain milling performance in fixed-speed mills through the liner wear-cycle.

Jan 1, 2012

By Balmer Neilly

In these days of arrested prosperity, when patience is tried and the future but dimly outlined, Canada's gold mining industry stands out as a beacon light shedding its rays of hope and confidence and demonstrating that there is still one product unaffected by Customs barriers and eagerly sought by all the people of the world. Some other forms of industry have hesitated and side-stepped. Some have cried for help, and in spite of public assistance, generously extended, they are still unable to demonstrate definitely their ability to resume the onward march. But gold mining has never hesitated. As an industry, it has bad an unique experience. When prices are high and conditions are generally referred to as prosperous, this industry is adversely affected. The cost of production goes up; profits are diminished; public sympathy is lacking; and, thrown upon its own resources, the industry tightens up its belt and throws its whole energy into an effort to improve operating conditions, and offset high prices by increased efficiency. When, in due course, depression follows inflation and prices ebb, the gold miner, through necessity, finds himself physically and mentally prepared to meet the situation.

Jan 1, 1932

By M. Boher, J. Lehmann, M. C. Kaerlé

"In the production of high quality steel, the understanding of the interactions between liquid steel and refractories and of their effect on steel purity and cleanness are becoming more and more important.An experimental study has been per-formed in order to estimate the importance of the reaction between a MgO-based tundish refractory and an Al-killed steel. The results show a pollution of the liquid steel:•the silicon content of the liquid steel increases due to the reduction of the silica of the refractory by the aluminum contained in the steel; and•a reoxidation of the steel occurs and the formation of an oxide layer on the refracto-ry, mainly composed of spinel crystals and of Ca-aluminates is observed.The transfer mechanisms of the various elements are analyzed."

Jan 1, 1997

By R. E. Ray

"As real estate for new development in urban settings becomes scarce, commercial high rises are being constructed above open passenger rail tracks and vehicular roadways. Rail and roadway overbuilds are treated as tunnels requiring emergency ventilation systems for train or automobile and truck fires. The value of floor space in residential and office towers poses challenges to engineers responsible for designing fan rooms and shafts for tunnel ventilation systems within the towers. This paper describes a case study of the unique incorporation of tunnel ventilation fan plants in the overbuild structure of a passenger railyard and an adjacent roadway.INTRODUCTIONTunnel ventilation systems are required for passenger rail and transit (subway) tunnels by the NFPA 130 Standard for Fixed Guideway Transit and Passenger Rail Systems, and the NFPA 502 Standard for Road Tunnels, Bridges, and Other Limited Access Highways requires tunnel ventilation systems for vehicular (road) tunnels. Passenger rail and transit (subway) tunnels are typically ventilated with a series of shafts placed longitudinally along the tunnels to provide piston relief for normal train operations and emergency ventilation of train fires utilizing reversible axial flow fans. The shafts are incorporated in dedicated ventilation buildings that house the tunnel ventilation fans and starters, switchgear to power the fans and other equipment and systems in the building, Programmable Logic Controllers (PLCs) to control fan operation with Supervisory Control and Data Acquisition (SCADA) software, and HVAC fans and ductwork to ventilate the spaces in the building. These ventilation buildings may also provide access to the tunnels below with ingress/egress stairs for use by first responders and firefighters entering the tunnels and train or transit system passengers exiting the tunnels in an emergency. A photograph of a passenger rail ventilation building that encompasses four tunnels is shown in Figure 1."

Jan 1, 2019

By P. Personnet, D. Wheaton, E. Couzinie, V. Demetriou, Brooks. W., G. Girault, M. Meyer, L. Charbonnel

A common problem in Gas Treatment Centers (GTC) from primary aluminium smelters is the temperature of the gas to be treated : above a threshold, filtering media are irreversibly damaged. The traditional way of dealing with high gas temperature is to dilute with fresh air, which implies over sizing - and therefore higher cost for - the GTC in order to have the capacity to treat this dilution air without compromising on pot suction. A system was developed which decreases gas temperature without having to use dilution air. This system is based on water pulverization in gas collectors. The water vaporization leads to a temperature decrease of the gas. A pilot system was trialed in our R&D unit. Satisfactory results led to the development of an industrial system based on Envirocare equipment (partnership), which was trialed in our production plant in Tomago (NSW, Australia). This patented system was then generalized in this plant, which is now using it with success during austral summer.

Jan 1, 2006

RISKGATE is an interactive online risk management system developed by the Minerals Industry Safety and Health Centre (MISHC; University of Queensland) to maximise health and safety performance in the mining industry through implementing continual improvement in management of major unwanted events. A comprehensive knowledge base has been captured for risk management of tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives, manual tasks and slips/trips/falls. This will be extended to outburst, coal burst and bumps, interface displays and controls, tailings dams and inrush in 2013. RISKGATE presents substantive and leading edge controls to assist industry stakeholders in the design, management and reporting of organisational and regulatory compliance requirements. From a broader industry perspective, RISKGATE provides an environment for knowledge capture and knowledge exchange to drive innovation and best practice in the identification, assessment and management of risk. By capturing operational knowledge from industry experts, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover in the coal industry. All major Australian mining companies are contributing topic experts to this broad industry initiative. In the first 24 months, nine coal mining companies nominated over 80 different experts who contributed over 400 days of individual time to the knowledge capture workshops. RISKGATE is the largest single Australian Coal Association Research Program (ACARP) occupational health and safety (OHS) initiative to date.

Aug 1, 2013

By Bill Parnell

"Friction winders and double drum winders have been used in the vertical shaft mining industry for over 100 years. In that time, there have been many changes made in the electronic and mechanical fields of hoisting, but few changes made in the manufacturing and performance of steel wire rope, until recently.In the past ten years, with the advent of high polymer thermoplastics, the industry has seen some major advancements in steel wire rope. By incorporating a polymer with steel, improvement of rope life and reduction of costly maintenance downtime has been accomplished.IntroductionThe Williams Mine is Canada's largest gold producer with an annual production of some 500 000 ounces of gold from 2.2 million tonnes of ore. The Williams Mine is situated in the Hemlo area of northwestern Ontario, approximately 40 Ian east of the town of Marathon. It is operated by the Williams Operating Corporation which is owned equally by Teck Corporation and Homestake Canada Inc. It is one of three adjacent properties forming the Hemlo gold camp."

Jan 1, 1995

By Pavel Vasak

The Laurentian University Virtual Reality Laboratory (VRL) has provided a unique platform for the development and testing of novel seismic and microseismic data processing and visualization technology. In collaboration with Vale?s Creighton Mine, the technology was implemented at the mine site and consists of a VRL system and site calibrated Seismic Excavation Hazard Map (SEHM) software. The SEHM was developed as a practical solution for the mine operator to identify areas of elevated, active rock mass damage processes caused by recent mining activity. This paper is a pictorial representation of the 3D stereoscopic demonstration of the Creighton Mine seismic data distribution and interpreted SEHM for the first quarter of 2009. A live demonstration is scheduled at the Laurentian University VRL as one of the conference field trips. The demonstration highlights the technology transfer of research concepts into a near-real-time excavation hazard system that utilizes the key aspects of virtual reality technology; the ability to integrate large datasets (geology, mine excavation, (seismic) monitoring data, production scheduling, stress model, etc.); the ability to manipulate and visualize large datasets in both space and in time (mining sequence); and the ability to review the datasets by a group of experts in an immersive (3D stereoscopic), collaborative environment to better understand the processes and context of the mining-induced seismicity and evaluate potential risks to the mining operation.

Oct 1, 2010

By J. M. Harrison

FIELD PARTIES of the Geological Survey of Canada have, in recent years, mapped several areas east and northeast of Flin Flon (9, 10, 12, 13, 14, 15, 118) (1). In all these areas the mineral deposits show a close geographical relation to faults although the immediate control of most of the known ore deposits appears to be folded structures in the rocks (8, 11, 18, 19). Air photographs and published geological maps were studied in order to ascertain whether or not the mineral deposits in the Flin Flon-Snow Lake mineral belt as a whole show any spatial relationship to faults. It was found that most of them do show a distinct geographical association with faults, or with topographic features that may be faults. It is further apparent on air photographs that a major lineament, for composite of lineaments, follows approximately the contact between gneisses and schists of the Kisseynew complex on the north, and Amisk volcanic rocks on the south. However, this Kisseynew lineament is not continuous and, especially in the eastern half of the district, it is exceedingly irregular in plan. Parts of this lineament have been mapped as faults (9, 10, 12, 14), other parts have been shown as stratigraphic contacts (1, 2, 21, 27), and still other parts have not been studied except by reconnaissance methods. It is suggested that the Kisseynew lineament may be due to a deformed fault that extends easterly from a point about 25 miles west-northwest of Flin Flon to a point at least 10 miles northeast of Wekusko lake and that the mineral deposits.

Jan 1, 1951

By P. R. Jones

"The paper describes the CDN$400 million expansion at Hudson Bay Mining and Smelting Co., Limited’s operations. The company has continuously produced copper and zinc at the Flin Flon metallurgical plant since 1930. The paper details the company’s operational turnaround since 1995 and “The 777 Project” which includes two new mines, expansion and modification of the concentrators, expansion of the zinc pressure leach plant, a new zinc electrolytic cellhouse and modifications to the copper smelter gas handling system to reduce ground level gas emissions. IntroductionHudson Bay Mining and Smelting Co., Limited (HBMS) was incorporated in 1927 to mine and process the world-class Flin Flon copper and zinc orebody. Ore concentration and metallurgical facilities were constructed in Flin Flon. The metallurgical complex capability is currently 89 000 tonnes of copper metal and 98 000 tonnes of zinc metal from both HBMS and purchased concentrates.Flin Flon, with a population of 7000, is in Manitoba and partly in the province of Saskatchewan. The location is isolated with Winnipeg 800 km to the south and Saskatoon 500 km southwest.Today, three underground mines feed the Flin Flon concentrator, one feeds the Ruttan concentrator at Leaf Rapids, 200 km to the north of Flin Flon, and Chisel North mine feeds the Snow Lake concentrator (Fig. 1).The Flin Flon volcanic massive sulphide proximal and distal orebodies are within the Flin Flon greenstone belt which stretches from the west of Flin Flon to the east of Snow Lake, a distance of 250 km. The belt is approximately 100 km wide before disappearing below the paleozoic cover to the south."

Jan 1, 2001

By G. V. Sirianni, G. E. Viens, R. A. Campbell, G. N. Banks

A combination shaft-electric furnace for the smelting of ores and the melting of metallized feed is being developed at the Mines Branch. When iron oxide pellets are smelted in this unit, they are preheated and partially reduced in the shaft before being transferred to the electric furnace where smelting is completed. Also, limestone flux added with the pellets is-preheated and calcined in the shaft. It has been demonstrated that, in smelting iron oxide in this unit, the throughput of the 250-kva electric furnace can be approximately doubled and the amount of electrical energy required can be very significantly reduced when the shaft furnace is operated in conjunction with the electric furnace. These benefits are achieved mainly by utilizing the sensible heat and latent energy contained in the arc furnace off-gases.

Jan 1, 1971

By M. Santaluce

"The revamp of critical process assets that require a significant plant outage (shutdown) presents a unique and demanding set of challenges for plant operators. They are executed in a more complex Brownfield environment, typically with limited working space and often involve unknown conditions or scope. For plant operators, such a project is often a high cost event both in terms of opportunity cost of lost production and the resource cost of labor and materials. It can also be a high risk event in terms safety, environment, and future plant reliability/availability. This impacts current and future performance or Overall Equipment Effectiveness (OEE). In our experience, the sequential nature of the EPCM approach does not provide the proper framework to facilitate the level of coordination, stakeholder cooperation and detailed planning required to adequately address the construction and shutdown complexity of a critical asset revamp projects. This paper proposes a more integrated approach to handling shutdown revamps of critical assets. Its main thesis is to involve the key performing stakeholder groups early in the project lifecycle (engineering team, procurement team, construction team and plant operations) to form an integrated shutdown management team that is focused on ensuring delivered results are aligned with project objectives. In this model, the construction team executing the shutdown/construction is preparing the detailed shutdown/construction planning concurrently with detailed engineering and procurement planning. This allows construction/shutdown requirements to influence engineering and procurement, with the desire to optimize safety, speed, quality and cost. The paper also discusses how to overcome the procurement hurdle in applying such an approach. The outcome of this integrated approach is better planning, coordination, communication and alignment between the project stakeholders, a shutdown/construction driven planning approach that more fully addresses the challenges of these projects and delivered results that are aligned with project objectives."

Jan 1, 2015

By Jack Young

U. S. Steel Canada Inc.’s Lake Erie Works is the last green field integrated plant to be built in North America. The plant was designed using the best available environmental technology to develop an environmentally friendly production facility. A summary of the technology and measures used in the construction of the plant are summarized in this paper.

Jan 1, 2015

By S. D. Graham

"The extractive metallurgy of gold is largely controlled by mineralogical factors such as the presence of refractory gold, particle size, gangue mineral associations, presence of preg-robbers, oxygen and cyanide consumers, and locking characteristics in base metal sulphides. Light microscopy and automated mineralogy techniques are regularly used to characterise the effect of these variables on gold recovery. However, despite their widespread application there are a range of limitations when grades are low. Typically, the analysis of low-grade samples requires the preparation and analysis of numerous polished blocks. This is often costly and time consuming, with complexities regarding analysing statistically representative particle quantities and problems overcoming stereological bias. This is compounded by the “nugget” effect and high tenor nature of gold mineralisation. X-ray Microscopy techniques have the potential to overcome many of these problems, in particular the statistical representivity of analysis, removing stereological bias and effectively locating phases that are present in ultra-trace proportions. In this paper we outline the potential benefits of employing X-ray Microscopy (XRM) in characterising gold losses from a typical Cu-Au porphyry project, which were illusive in 2D based analysis. The talk will also outline additional application areas of XRM within the extractive value chain."

Jan 1, 2017

By D. Sharma, A. K. Singh, R. Singh, P. K. Mandal, M. Sarkar

"This paper deals with the stability investigations carried out at the XIVth seam of Jitpur colliery. The study was conducted to investigate the possible causes of roof cavity formation and face spalling at the middle slice face of block-3 longwall panel and to suggest remedial measures. The instrumentation and monitoring work was carried out in the panel over a period of nine months. On the basis of observations, it was found that if the maximum face span was reduced from the existing 4.8 m to 3.6 m, and if the face time schedule cycle was reduced from a maximum of 37 days to about 18 days, this problem could be eliminated. The recommendations of CMRI have been implemented in the middle slice face of block-4 panel with success. IntroductionModerate to steeply dipping, undisturbed seams of uniform thickness are worked by way of inclined slicing parallel to walls. In this method, the seams are treated as a combination of several moderately thick seams dipping parallel to roof and floor. Numerous variations of multislice mining have been used worldwide to get high coal recovery under local conditions of geology, subsidence control, proness to spontaneous combustion, statutes and economics. Multislice mining can proceed either downward descending from the roof or upward ascending from the floor. Ascending methods require backfill behind the working face to provide a base for the next slice. It is also adopted for surface protection against subsidence or mining under a massive roof. This paper presents a scientific study conducted in Jitpur colliery, IISCO where a 9 m thick seam is mined in three slices in ascending order with stowing."

Jan 1, 2002

By G. R. Parslow

U, Fe, Mn, Ni, Cu, Zn and Co data for the sediment in both Key and Seahorse lakes, which overlie portions of known economic uranium deposits in the region, are presented. With the exception of U, Fe and Mn, the elemental distributions can be considered anomalous, in a statistical sense, in both lakes. The U values are of particular interest in that Key Lake is not anomalous, whereas Seahorse Lake is markedly anomalous. Tentative correlations made with background data from other surveys in an attempt to differentiate between anomalous and background values indicate that deviations from linearity in a distribution, and not absolute mean or maximum values, are indicative of anomalous samples within the distribution.

Jan 1, 1979