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By Ali Hashemi, Anna P. Perry

The PQ Deeps (PQD) is a production zone located at Newmont’s Musselwhite Mine in northern Ontario. Development started for the PQD in late 2017, and the first stopes were mined starting in early 2021. Unlike most historic longitudinal stoping of narrower orebodies at Musselwhite, the PQD is a wider orebody following the plunge of a fold hinge and is extracted primarily by transverse stoping. Some geotechnical challenges were experienced during early stoping efforts, necessitating design changes throughout late 2021 and early 2022 to optimize the stope design. This work describes the mining methods and design changes to transverse PQD stoping based on geotechnical lessons learned during early stoping efforts.

Jan 1, 2023

By L. Bichler, A. Siebert-Timmer

In this research, novel YSZ ceramics doped with 5 mol% Nd2O3 were manufactured via Spark Plasma Sintering (SPS) process. The sintered Nd2O3-YSZ ceramics were subjected to a static supercritical water environment at a temperature and pressure of 400 °C and 31 MPa, respectively. The weight loss and microstructure development of the sintered ceramic before and after exposure to supercritical water was studied. The results suggested that Nd2O3 addition significantly improved the degradation resistance of the YSZ ceramics. This was attributed to the improved phase stability of the 5 mol% Nd2O3-YSZ ceramics, since X-ray Diffraction (XRD) studies showed that the cubic stabilized matrix in these ceramics was retained after exposure to supercritical water. In comparison, pure YSZ ceramics exhibited a rapid degradation behavior as well as a phase change.

Jan 1, 2014

By G. R. MANSON

The Brisco Barite Mine lies 70 km south-southeast of Golden, British Columbia. Barile mineralization occurs in a northstriking brecciation zone within Ordovician-Silurian Beaver/ oot dolomites and quartzites. Brecciation was caused by faulting related to the Mount Forster-Steamboat Fault. The main barite vein occupies a fault zone and is up to 12 m wide and over 250 m long. It is light grey to white, fine grained and compact; BaSO4 content is 9/. 70 per cent. Production started in 1945 and has continued to the present. Barile originally was removed from an open pit; later, an adit, begun in 1957, reached more than 240 m along the vein, 15 m below the pit floor. Today ore is hoisted from a decline resting some 37 m below the pit floor.

Jan 1, 1984

By L. G. Morrell

Introduction A Self-Dumping cage which combines the features of a small skip and a cage has been used in a vertical winze between the 2,000 and 2,500 levels at the Coniaurum mine for the past three years, during which time its success has been demonstrated by uninterrupted service and low maintenance charges. lt was designed by John Reddington, mine manager, and was built under his supervision in the Coniaurum mine shops. Being new in many of its operating features, a small-scale model was made and tried before the final construction was undertaken. The mechanical performance of the model suggested a few minor changes that were incorporated in the final drawings. During its three years of use, the automatic dumping device has saved the expense of deck-handling of the cars. This actually represents a gross economy of something over four times the cost of construction and installation, which totalled $1,325. The cage, empty, weighs 2,200 pounds, of which 500 pounds represents the weight of the dumping accessory and necessarily heavier construction. Besides a considerable financial saving, the time saved in unloading increases the daily hoisting capacity of the winze. In raising ore from the 2,500 level, five minutes are required for a complete trip. Allowing one minute for the alternative of decking, we believe that the automatic dumping has increased the capacity of the winze hoist nearly 20 percent.

Jan 1, 1933

By Mary Jean Buchanan

The last twenty years have seen the advent of environmental concerns and sustainable development, and the industry has witnessed the rise of Environmental Management Systems and their registration through several international standardization systems such as EMAS and ISO 14001. Beyond EMS and ISO 14001, which new goal the mining industry should aim at. Life-cycle assessment (LCA), another tool from the Environmental Management System series, is also on the rise and currently the object of an international standard (ISO 14040:1997). Through LCA, it is possible to assess the environmental aspects and potential impacts associated with products and services, taking into account all the activities required for its fabrication, its use, its transportation and its disposal. How could LCA be applied to the mining industry ? Is the international market pressurizing on mining companies to supply an ?environmental ore?? What about the automobile industry and its use of LCA ? Will it influence the ferrous and non-ferrous metal industry, suppliers of raw materials ? This paper presents a review of possible applications of LCA for the mining industry as well as world trends.

May 1, 2001

By Md. Rashedul Islam

Magnetic data was collected from the Yeoju historical sites using the fluxgate gradiometer through six sites & several grids. We measured the vertical gradient by the FM256 Fluxgate gradiometer. The readings were logged every half meter. The obtained data were processed and treated to introduce a high quality magnetic image. The gradiometer results defined various positive and negative magnetic anomalies, which revealed the existence of several archaeological features of different shapes and sizes. The study of the process magnetic images give us a concept that the subsurface features are caved shape stone chamber tombs, burial mounds, deep room structure, Yeoju mausoleum, pagoda?s square foundation stones, walls etc. All these are superior work of early Goguryeo inheriting orthodox Silla style. So, the study area may have great archeological interest.

May 1, 2009

By J. F. Nie

Mechanical properties of precipitation hardenable magnesium alloys depend critically on the chemistry, structure, morphology, orientation and distribution of strengthening precipitates. It is therefore important to gain an improved understanding of these information and their correlations with mechanical properties. Our recent studies indicate that additions of 1-2 wt% of Zn to a Mg-6wt%Gd alloy result in a substantial enhancement in precipitation hardening and in creep resistance. If the strength and creep resistance of the resulting ternary alloy are to be further enhanced for commercial applications, then a detailed characterisation of the strengthening precipitates in these alloys is required. In the present study, the precipitates formed in a Mg-6Gd-1Zn-0.6Zr (wt%) alloy, peaked aged at 250°C, have been characterised in detail using transmission electron microscopy and 3-dimensional atom probe field-ion microscopy. It is found the peak-aged microstructure contains a dense and uniform distribution of precipitate plates that form on the basal plane of the matrix phase and are typically less than 1 nm in thickness. Detailed analyses of the structure and composition of these basal precipitate plates will be presented and discussed in the context of previous work on other Mg-RE¬Zn alloys of similar compositions.

Jan 1, 2006

By William M. Luff

"The Bathurst area has recorded mining production as early as 1837, although the bulk of the production has come in recent years. Production has been mainly from the well-known massive sulphide deposits, but vein, gossan, and a variety of other deposits have also been mined. This paper summarizes the history of the mined deposits, along with tonnages and grades produced. A number of ""firsts"" have been noted in the Bathurst area. The A Zone deposit, located in the Heath Steele area, was the first in the world discovered using airborne electromagnetic methods. Heap leaching of gold from the gossan zone at Caribou was the first operation of its kind in Canada. The Keymet mine was the first base metal (lead-zinc) mine in New Brunswick. For the past few years, the Brunswick No. 12 mine has been one of the largest zinc mines in the world.IntroductionThe Bathurst area (Fig. 1) first had mining production in 1837 when copper was mined from a deposit on the Nepisiquit river (MacKenzie, 1958). The majority of the production, however, has been in recent years from massive sulphide deposits, but there are also other significant operations. . Table 1 is a summary of Bathurst area mineral production, showing concentrator feed tonnages and mill feed grades. The table does not include peat deposits, sand and gravel, dimension stone or rock quarries. Figure I is a general geology map of the Bathurst area, indicating deposit locations. The deposits are divided into four categories: massive sulphide, vein, gossan and other. The deposits in each category are described in chronological order of exploitation."

Jan 1, 1995

By D. Magoon

The metals industry has enjoyed a resurgence in prices and demand for its commodities during the global surge in economic activity that began in 2005. This success has brought with it an unprecedented demand for professionals in all sectors of our economy. Nowhere is that more true than in the mining and metallurgy sectors. However, this welcome improvement follows on the heels of almost two decades of challenging markets for the mining and metallurgy. Our sector's protracted economic slump created a paucity of demand for professionals that had several consequences. Our industry came to be viewed as a low ?tech, uninteresting place to work. Low demand for professionals encouraged students to seek other career options. Reduced demand for graduates, coupled with diminished program funding by our sector, resulted in dramatic shrinkage in university mining and metallurgy programs. This paper explores the lessons to be learned from our recent economic history and discusses some strategies for addressing our image issue. Attracting and retaining good employees is also strongly influenced by a company's reputation and record as a good employer. This reality is very well illustrated by the findings of an international survey undertaken by Towers Perrin in 2005 of 86,000 employees of mid-sized and large companies in 16 countries. The key findings related to attracting and retaining employees are presented. These findings are also discussed in the context of their specific applicability to the mining and metallurgy industry.

Jan 1, 2007

By B. T. Lu, J. L. Luo, H. X. Guo

This paper investigated the synergistic effect in the slurry-erosion process of carbon steel. In line with the mechanisms of material loss, the synergism due to interaction of erosion and corrosion was divided into the corrosion enhanced by erosion and erosion enhanced by corrosion. The erosion-corrosion tests were conducted with A1045 steel in slurries containing silica sand. Experimental results showed that the rotating of the sample in corrosive media raised both OCP and corrosion rate, but the impingement of solid particles did not affect the corrosion current significantly. In the quiescent solutions, the Faraday's law gave a good prediction for the weight loss caused by corrosion but for rotating samples, the weight loss experimentally measured was virtually greater than that predicted by the Faraday's law, indicating that the corrosion-enhanced erosion could occur in corrosive fluids in absence of solid particles. A half-logarithm relationship was observed between the weight loss due to corrosion-enhanced erosion and the anodic current density.

Jan 1, 2004

By L. Gawlik

Since the beginning of the 20th century, coal has been the world?s main source of primary energy. In the last few decades, consumption of coal has gradually decreased in some European countries and elsewhere due to the introduction of other energy sources. Regardless, industry continues to use solid fuels for energy production despite of their association with carbon dioxide emissions (about 7 billion Mg). For global development going forward, it is important to estimate what level of energy consumption can be expected as far into the future as the next few decades. To answer this question, specialized global institutions such as the International Energy Agency, the World Energy Council, the World Coal Institute, the U.S. Energy Information Administration, the International Institute for Applied Systems Analysis, as well as oil companies (BP, Shell), conduct periodic forecasts of world energy consumption. The development of such forecasts is very complex because their reliability is influenced by many factors that are difficult to estimate, such as economic development, population growth, climate change, and public awareness. We are all aware that the global demand for electricity will rise significantly in the coming years as a result of anticipated population growth, industrial development, rising living standards, and the general development of civilization. The world?s mineable resources in 2010 were as follows: coal 665.6 million Mg, brown coal 195.4 billion Mg, oil 163 million Mg, and natural gas 185.5 billion m3. The annual global primary energy demand in 2008 was more than 12 billion toe (12,267 Mtoe). In 2006, electricity production in the world amounted to 18,921 TW?h. The structure of the primary energy mix in TW?h (2006) was as follows: coal 41.0%; natural gas 20.1%; nuclear fuel 14.8%; hydro energy 16.0%; liquid fuels 5.8%; and other renewable energy sources 2.3%. The European Union (EU) is one of the largest coal consumers in the world. In 2010, the EU-27 produced 396.1 million Mg of brown coal, and 132.9 million Mg of hard coal; 188 million Mg of coal was imported from outside the EU. The largest hard coal producers in the EU-27 are Poland, Great Britain, Germany, the Czech Republic, and Spain; major brown coal producers are Germany, Greece, Poland, the Czech Republic, and Hungary. For many years, the Polish energy sector has been based on domestic fuel sources ? hard coal and brown coal. The characteristic feature of the Polish balance of primary energy resources is a very high share of coal ? much higher than the world average. Pursuing the decarbonisation of the Polish economy may jeopardize Poland?s energy security, leading to a significant increase in electricity prices, which would hamper the country?s economic development. Price volatility and supply uncertainty are now the dominant features of the international markets for oil and natural gas. The high share of these fuels in meeting energy needs is the reason for unrest in many countries, including those in the EU. Under these circumstances, coal may become the stabilizing element of EU energy security.

Aug 1, 2013

By Amin Jafari

Macrosegregation has always been an important issue with the solidification processes, particularly in Direct-Chill Casting of Aluminum alloys, where uneven properties, surface and bulk defects and limitations in productivity can be arisen due to macrosegregation in the cast product. Following the global attempts to practically predict the macrosegregation, in the present work, a numerical model was developed based on an industrial scale DC casting process to simulate the solidification and macrosegregation in an Al-4.5%Cu billet. Interesting aspects of this investigation are concerned with an efficient numerical scheme to keep simplicity, consistency and desired physical resolution of the solidification phenomena together. In the mathematical model, coupled conservation equations of mass, momentum, energy and species were solved numerically using finite volume method. A different numerical scheme, called SIMTLE, was introduced to link the energy and species equations with the phase diagram of the alloy. Calculations were performed on an industrial case and obtained results were compared to available experimental data to assure the performance of the model. Different macrosegregation features were predicted and discussed on the solidifying Al-alloy billet.

Oct 1, 2011

By C. Gaubert, G. Bourassa

"The construction or rebuild process in the anode baking furnaces has been modeled with the software Rockwell Arena, in order to minimize the process cost and risk. The case study was focused on the sectional rebuild (""on the fly"") that needs a high coordination of the material inventory, the on-site personnel and the construction/production schedule. Multiple entities and resources were allocated for the different part of the process (in-furnace process, prefabrication, materials transportation, etc.). Logic flow charts and VBA macros were used to simulate the space utilization (including cranes utilization) and interaction with production. MS-Excel output files can show user-friendly results."

Jan 1, 2006

By J. R. Pacheco

Paranapanema group has decided to implement the business system SAP R/3 in all companies of the group in order to replace all current applications. This project has taken nine months to be completed. This paper describes the phases of this implementation, with focus on the Plant Maintenance component. In addition, it gives an idea of the effort required to implement SAP R/3 on an organization the size of Paranapanema group.

Jan 1, 2007

By C. F. Gleeson

"I HAVE BEEN ASSIGNED the pleasant task of adding a last word in way of summary to this session. I think that the trend set in having a geochemical session at the CIM Annual General Meeting is a good one and I hope it will continue so that members of the mining fraternity can get together on a regular basis and discuss geochemical problems peculiar to our Canadian scene. A series of interesting papers have been presented on what has been considered by many in the past as not only a problem area for geochemistry but even an impossible one. The papers should help dispel some of these fears. Lack of development of geochemical techniques in the Shield has been due to a variety of factors, many of which have been mentioned. However, I feel that one of the main reasons for this lack of development has been timidness on behalf of many people to get out and do the necessary work which helps produce answers to many of the questions asked. New developments and applications of geochemical methods in the Shield will not be done by the faint of heart but by those who have the curiosity, interest, imagination, drive, resources and, most of all, the intestinal fortitude to stick to it and not give up because results or conditions do not meet with preconceived notions. Another element that will be needed by those who will successfully apply the techniques and who will be responsible for new breakthroughs is the systematic approach to sampling and analysis and the integration of geochemical, geological and geophysical results. Erratic sampling patterns - a sample here and a sample there - generally lead to more problems than solutions."

Jan 1, 1971

By Michel Noël

This paper presents a partial compilation of adopted measures of waste rock dump closures at mine sites located in Canada and Alaska, where the climate includes cold winters. The paper also presents the selection process that was followed for some of those mine sites. Mining operations usually generate waste rock that can sometimes result in very large quantities. Additionally, the nature of the ore body and the host rock will often introduce environmental impacts. These impacts need to be managed not only during the operations but also in the long term. Mine closure plans consequently have to address the long term issues that sometimes require perpetual treatment. Closure planning often involves the evaluation of risks associated with environmental and financial liabilities. It needs to consider the science, some common definition of objectives, and there will be a need to manage resources and schedules. Closure planning is essentially an exercise in constrained decision making. A performance and risk based ranking matrix is often developed during this selection process to identify the preferred option(s). The case studies presented in this paper provides a few examples. The level of knowledge on acid rock drainage from waste rock dumps has increased considerably over the past decades. It did not necessarily increase the level of complexity of the adopted closure methods, as the selected closure methods are often kept simple. A common approach consists of stabilising the slopes of the waste rock dumps material by resloping and then covering the waste rock with a growth media to support vegetation. Such covers prevent direct contact of animals with the waste rock material, minimise erosion and reduce infiltration to various degrees. The inclusion of water treatment is obviously dependent on the water quality being released.

Nov 1, 2008

By K. Pienimäki

Boliden Harjavalta Oy has produced copper since 1945. The essential idea has always been continuous development of process efficiency and environmental friendliness by using the Best Available Techniques (BAT). The ongoing development step is to increase the production capacity up to 210 000 tpy of anode copper and 155 000 tpy of copper cathode. One of the focal issues in this action is modernization of the copper refinery to utilize permanent cathode technology. This paper describes the refinery project and the technology used in it.

Jan 1, 2007

By V. Pouyafar

In recent years semi-solid processing of steel alloys has gain more attention among researchers. Production of high quality complex steel parts with higher mechanical properties is the final goal for all these researches. A thorough understanding of the flow behavior of the metal under investigation is the key for a successful process design. The material used in this research is M2 tool steel. The experiments were performed using a Searl-type concentric cylindrical rheometer which is specially designed for high temperature rheological measurements up to 1500 ºC. The rheological techniques were consisted of continuous cooling experiments and isothermal holding and also shear rate step change experiments for different solid fractions. Based on the rheological data a single phase thixotropic model has been derived and adopted to the measured data. The state of the microstructure has been applied through a structural parameter. The model fits well with the experiments.

Oct 1, 2011

By Blair Hrabi

Introduction; ?Risks Associated with the Resource Estimation Process; ?Limitations of Available Data; ?Geological and Structural Control of Mineralization Trends; ?Recognizing Multiple Mineralization Controls and Complex Trends; ?Accurate Geodomaining; ?Conclusions.

May 1, 2013

By D. A. Brown, C. Lowe

"Abstract -A multi-sensor (electromagnetics, magnetics, gamma-ray spectrometry, and VLF) geophysical survey was recently conducted in the Purcell Basin of southeastern British Columbia in an area encompassing the world-class Sullivan Sedex deposit. The purpose of the survey was to geophysically characterize the known mineral occurrences and to develop strategies to enhance future mineral exploration in the basin. Follow-up investigations of geology and measurements of rock physical properties helped constrain interpretations of the geophysical data sets.Despite extraction of more than 90% of the ore from the Sullivan deposit, it is clear that the mineralization there, as well as at other Sedex occurrences surveyed, is characterized by high conductivity values, strong bedrock conductors, and elevated magnetic anomaly values. The albite-sericite alteration which accompanies this mineralization yields high potassium and low thorium-potassium ratio values. Associated Moyie gabbro is characterized by low electrical conductivity and radioelement concentrations and by high magnetic anomaly values. The study has also aided exploration for other mineral deposit types including stratabound Cu-Ag, placer gold, vein and disseminated basemetal deposits. In addition, the geophysical data have helped constrain geological interpretations of the basin."

Jan 1, 1998