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By A. L. Williamson

Bio-mining, the use of micro-organisms to recover elements of interest, is potentially useful for the economic extraction and recovery of ore metals from a variety of ore deposits, including the lowergrade uranium deposits found in the uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario. The metabolism of chemolithotropic bacterium Acidithiobacillus ferrooxidans depends on an ability to derive energy and reducing power from the oxidation of ferrous iron found in a varirty of iron sulphide minerals associated with base, precious metal and uraniferous ores. The characteristics of this bacterium, especially the ability to oxidize both iron and sulphur with an associated high tolerance of low acidity, allow the organism to contribute significantly to bio-mining processes. Under ideal conditions, A. ferrooxidans promotes the oxidation of ferrous iron in low sulphide ore materials, breaking the crystal structure of the ore minerals .releasing protons to the surrounding solutions, thus promoting the dissolution of uranium and rare earth elements, among others. This paper provides an overview of elemental dissolution and release of uranium, rare earth elements and investigates the acid generating potential of the final residues, from a series of environmentally controlled, biologically-mediated uranium ore extraction experiments. The findings will be used to guide in the design of larger scale bio-leaching experiments to further assess the potential for successful bio-mining operations along the Quirke Syncline.

Aug 1, 2010

By Andreea Catalina Gluhoi

The oxidation of propylene and methane has been investigated over two series of Au/MOx/Al2O3 and Au/MIOx/MIIOx/Al2O3 catalysts (M, MI, MII =Li, Rb, Mg, Mn, Ce, Zr). Whereas the effect of the presence of MOx or MOI x/MOII x on the oxidation of methane is relatively small, a large enhancement in activity is observed for propylene oxidation. Synergistic effects have been observed by combining ceria or a transition metal oxide (high oxygen storage capacity) with an (earth) alkali metal oxide.

Oct 1, 2003

By Tom Setterfield

Monster Copper Resources ?Junior focused solely on IOCG deposits ?Founded by ex-WMC geoscientists ?Properties in Brazil, Wernecke Breccias (Yukon), Central Mineral Belt and Nova Scotia Nova Scotia ?JV with Wallbridge Mining Company ?Ongoing Story ?Presented as a case study in generation and implementation of IOCG exploration program

Apr 1, 2005

By Rodney S. Read

This paper outlines a reasoned argument why no large-scale fracturing or faulting will be induced in the host rock by a deep geological repository (DGR) for nuclear fuel waste. Four DGR designs in three possible host rocks, including crystalline and sedimentary rock types, are considered. The reasoned argument draws from results of previously conducted thermal- mechanical analyses and new scoping calculations, along with evidence from experiments conducted in Canada and elsewhere. It is concluded that large-scale fracturing in the far-field is implausible given the expected in situ stress conditions in relation to rock strength. Near-field damage development and fracturing are expected in DGR scenarios in the different rock types, but these near-field effects are not expected to lead to large-scale fracturing that could compromise the integrity of the DGR and surrounding rock mass. Additional analysis and characterization activities are recommended to further validate the reasoned argument. Thermo-poroelastic loading of the rock mass is identified as one possible driving mechanism that should be studied further.

May 1, 2009

By S. F. Dudka, T. Dang, M. L. Wong

Abstract - The Nui Phao W-F-Cu-Au-Bi deposit is located in one of the poorest regions of northern Vietnam. The deposit is currently undergoing a pre-feasibility study by Tiberon Minerals Ltd., with a view to developing what would be the largest WO3 mine and one of the five largest fluorite mines in the world. The project is being planned in close compliance with World Bank and national guidelines for environmental and social protection. Development of the mine is anticipated to bring the following benefits: remediation of serious pre-existing environmental conditions (natural and anthropogenic heavy metal contamination and acid rock drainage); provision of employment and training, and thereby wealth, to local communities; significant tax and royalty payments to government, which will be reinvested as social spending; and development of municipal and industrial infrastructure to build sustainable post-mining communities. The role of governments at all levels is critical in guiding and facilitating this process. This paper was written prior to development of the mine, and relays the intentions of the developers. Future studies will be needed to evaluate the degree of attainment of sustainable development objectives, both during mine operation and after closure.

Jan 1, 2003

By K. H. March

In the present very highly competitive condition of the bituminous coal business, it is becoming increasingly apparent that coal mines which do not lend themselves to efficient mechanization cannot long survive. It would seem that those mining operations best fitted to survive the struggle for existence are burdened with the considerable capital and maintenance cast of carefully selected mechanical and electrical mining equipment. The ever changing conditions of coal mine operations require equipment which is adaptable to a variety of uses; and investigation of the mechanical and electrical equipment in most mines will show that the operating duty of much of this equipment is considerably different from that duty for which it was originally selected. And it would appear that one of the essential qualifications for a successful mine management is a marked ability to get satisfactory operating results from equipment which has been transferred from some other operation, rebuilt, rearranged, or in some way adapted to the job at hand. As a striking example of such mechanical ingenuity, many of us recall that the first longwall jigging conveyor used in Nova Scotia was built in Sydney Mines from odds and ends in the scrap pile at a total cost of less than $50.

Jan 1, 1930

By Ernest A. Hodgson

WHEN excavations are made, at depth, in hard brittle rock structures, as in certain mines in India, in South Africa, and in Ontario, the pressure due to overburden, together perhaps with inherent geologic strain, tends to become concentrated in the walls of some of these openings and the rock bursts, often closing the adjacent drifts and scopes and presenting a serious menace to the miners. Where the rock is much fractured and faulted, the danger is greater, since the pressures tend to shift without warning from point to point, sometimes within a few hours. Attempts have been repeatedly made to find some physical property of the rock which will change with pressure, which can be measured for rock 'in place' in the mine, and which will give an indication of the state of strain, thus warning of an approach to bursting conditions. Some of the properties tested have been the speed of propagation of elastic waves in the suspect rock, variations in temperature due to pressure changes, rate of closure of openings or shifts along fault planes, strain gauge measures, and others. Each of these has proved unsatisfactory for the purpose. The most promising method so far proposed has been the study of the very faint, sub-audible snaps (microseismims) which are produced in rocks under pressure. Such a study has been in progress at Lake Shore Mines since May, 1942. Instruments designed to pick up, amplify, and record the microseismims were perfected and a programme of observing, using the microseismic method, has been carried through with persistent diligence and at considerable expense. In 1943, experience with the method in a pillar section on the west side of the Lake Shore mine gave much promise of predicting bursts. A very heavy burst on January 29th of that year occurred in the exact section of the mine covered by the instruments, and the records indicated a measure of prediction. In response to repeated requests for information, a number of reports were given out, among others a radio talk by the writer over CJKL (Kirkland Lake), which was reported in full in the Northern News . Also, a detailed account of the occurrence was given in an illustrated paper by the writer (l).

Jan 1, 1945

By J. Vanderlaan

A proposed method of applying high-speed, non-destructive part scanning technologies to the production process of UO2 (Uranium Dioxide) fuel pellets is presented. The scanning process examines each pellet individually for correct surface roughness and any surface imperfection or defects. Using optical scanning methods, which consist of laser and CCD camera technology, the complete circumferential surface of the pellet is examined to meet the reactor fuel bundle specifications.

Aug 1, 2010

By Donald J. Farrish

"Mr. Chairman and fellow CMP members, most of these remarks will be made with particular reference to copper concentrate but the basics apply generally to other metal concentrates as well.For very good reasons, using copper as an example, smelting capacity usually is located either close to mine production or close to areas of high copper consumption. The mine producer can add on smelting capacity to insure that the copper in his concentrate can be processed into a marketable form under more or less controlled conditions including costs. On the other hand, the consumer wishing to assure a better supply of copper likewise can build smelting capacity and offer treatment charges attractive enough to discourage mines from investing in their own facilities. In this regard, freight is an important factor. Bulk shipments from the heart of Africa with a large overland component are uneconomic whereas concentrate movements from Australia or South America compare favourably with smaller metal shipments.A mine project which incorporates smelting capacity, will often, through the presence of this capacity, encourage active exploration and development of additional concentrate production in the vicinity. The usual result is that new mines within reasonable distance of the smelter will be able to avoid the capital required to build their own smelting and refining facilities and that the existing facilities will expand to appreciate economies of scale."

Jan 1, 1978

By S. Brophy

Controlled Short Circuit ? Metal Inert Gas (CSC-MIG) welding is a process that can be referred as a "Cold Welding" technology. The CSC process is based on accurate control of the welding wire position, thus the mandatory requirement for the automation of the process. One of the main advantages of the CSC-MIG process is the rapid solidification of the deposited material, resulting in weldments displaying low porosity contents, and enabling the joining of thin sheet materials. These characteristics render this process an ideal one for freeforming of components, where rapid solidification would be efficacious. This presentation will focus on the progress made towards the freeforming of Al-based components in the NAIN laboratory at McGill University. The relationship between the filler metal used, freeforming (deposition) parameters, resulting microstructure and mechanical properties will be presented.

Jan 1, 2011

By Thomas E. Shumka

ASTM E2905 describes a two-part standard for electromagnetic methods for preparation and examination of ring gear teeth in the mining sector for SAG and Ball Mill ring gear drives, including pinions? particularly on the addendum, dedendum, and root areas. This practice addresses the need to detect surface breaking flaws electronically and to have the ability to accurately size any surface breaking cracks found on cast and forged SAG and ball mill ring gear and pinion teeth faster and more effectively than other methods. Eddy-current surface arrays are seeing increasing use throughout the industry for the detection of surface breaking flaws in conducting materials. Example applications include examinations of pipelines, bridges, engines, aerospace structures, and any conducting material for surface breaking flaws including cracks. In addition, model-based methods are being used to size cracks accurately found in the addendum, dedendum, and the root of SAG and ball mill girth gear teeth. As visual interpretation of a surface breaking discontinuity on gear teeth is the normal analysis, the colors and 3D images that are provided with this technique, help with visualization and therefore are absolutely invaluable in such circumstances. This practice will help to standardize the use of this nondestructive testing approach.

May 1, 2013

By Julia Pflieger, Manfred Russ, Johannes Gediga

This paper shall show an economic feasible approach to implement Greenhouse Gas (GHG) reduction measures into the mining and metallurgy industry. The goal to improve energy consumption is directly linked to the reduction of GHG emissions and therefore directly in correlation with the economic viability. A baseline scenario of the considered reference system and of the respective reference year has to be defined, mapped and analysed. In a second step an analysis of the same operation using available and prospected Best Available Technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified reduction potentials are reported and the GHG emission reductions are put into relation to the investment cost of the new process technologies / process adaption to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap implementation into the company's business operations. The GHG reduction roadmap is developed using ratios between GHG reduction and investment / operating cost to get an indication for a sequence for implementing carbon emission reductions measures.

Jan 1, 2010

By A. A. Nourbakhsha

During the last few years, low cement castable refractories found more application in industry, because of good low and high temperature mechanical properties.In the case of alumina based castables ,usually fume silica or reactive alumina are used as superfines in the matrix to form mullite at high temperature which depends to source of alumina . Mullite network formation improves the hot mechanical properties and thermal shock resistance of bodies. The mullitisation of andalusite (so called primary mullite) also produces a certain amount of rich silica glass, part of it being expelled out of the grain. This phenomenon restrict the application of andalusite low cement castable in pig iron ladle. In this research, firstly 8 pig iron ladles from ESC(esfahan Steel company) with different conditions selected and monitored during usage to determine of main factors affecting on corrosion of refractories. Results showed that tap to tap time and undischarged pig iron are the main ones.Therefore monolithic refractories such as castables which increase thermal shock resistance could be substituted. Regarding to ternary phase diagram of Al2O3-SiO2-CaO ,fumed silica was selected as fine particle.After optimization of particle size distribution by using of modified andreasen equation and rehological properties ,different mixture were composed with andalusite ,fume silica, reactive alumina,secar 71 ,SiC and kyanite.All aggregates system components were mixed dry for 1 min in hobart mixer .After water addition wet mixing was continued until getting flowing about 4 min.The ready mixes were poured in the moulds of of 25mm X 25mm X 140mm with vibrations .After demoulding the samples were cured for 24 hrs and dried at 110OC/18hrsand then fired at 1100-1500OC. Physical ,mechanical ,phase analysis(XRD) and microstructure studies (SEM)were carried out according to ASTM standards. Results showed that by addition of kyanite ,more mullite phase formed through the matrix but,because of expansion occured during this phase transformoration, some cracks formed and mechanical properties decreased.By SiC addition the silica film on the surface of SiC lead to improvement of mechanical properties at high temperature

Oct 1, 2011

By Les F. Sawatsky

Surface drainage, particularly mine closure drainage, must be properly considered during all stages of mine planning because it presents constraints that are critical to economic mine operation, minimizing environmental impacts and ensuring compliance with government regulations. Deficient mine site drainage increases costs of operation, causes unnecessary environmental impacts and may result in regulatory violations. The scope of this paper includes stream diversions around mine areas, drainage systems within the mine disturbed footprint, and closure drainage works to control surface water, ground water, erosion, sedimentation, and seepage discharges following mine operations. Developing selfsustaining drainage facilities upon mine closure, requires a mine plan that develops appropriate topography and constructed drainage courses that replace the function of pre-disturbance drainage systems without aggravated erosion and deterioration. Drainage criteria, particularly closure drainage criteria, represent important constraints on mine planning and are best considered by integrating drainage features into the mine plan well in advance of mining activities. Integrated mine planning by a multi-disciplinary team is recommended to achieve closure objectives at minimum cost and maximum effectiveness The geomorphic approach to channel design is an effective means of providing a drainage system that has the appearance, function and longevity of natural systems. By incorporating this technique into closure drainage planning, mine operators can construct sustainable (walk-away) drainage systems that require little or no maintenance in the long-term. This paper presents a process by which drainage criteria and associated mine plan constraints can be integrated into the mine planning process. This paper outlines the process for detailed design of drainage facilities, particularly closure drainage systems that are designed by the geomorphic approach.

May 1, 2009

By Y. Konishi

This paper reviews the mechanism and kinetics of bioleaching of chalcopyrite by the thermophilic archae Acidianus brierleyi in batch and continuous-flow reactors. Rate data for the batch bioleaching of chalcopyrite concentrate were collected to clarify mechanism of the chalcopyrite bioleaching with A. brierleyi. The chalcopyrite leaching was markedly accelerated in the presence of A. brierleyi, and greater than 90% copper leaching was achieved within 10 days. Chalcopyrite leaching took place predominantly as a result of direct attack by adsorbed bacteria on the sulfide surface, the chemical leaching with ferric iron being insignificant. Batch rate data collected under a variety of operating variables were analyzed with our batch bioleaching model, in order to estimate microbial kinetic and stoichiometric parameters for the microbial growth on chalcopyrite. The batch model and the estimated parameter values were used to find optimum operating conditions. Moreover, the batch model was extended to describe the bioleaching in continuous-flow stirred tank reactors. Simulations based on the continuous reactor model and the estimated parameter values were used to predict the leaching fraction as a function of the number of reactors connected in series.

Jan 1, 2007

Mining Impact in Water Quality: Understanding the conflict Mining is an industrial process Metal mines that chemically process ore to concentrate metals such as copper and gold use more water than non-metal mines such as coal, salt and gravel. Tailing Ponds Water contaminated with high concentrations of metals, sulphide minerals, dissolved solids, or salts can negatively affect surface water quality, aquatic ecosystems and groundwater quality.

May 1, 2013

By Chan-ho Park

As the building has recently become bigger, higher, and freeform, a technology called BIM(Building Information Modeling), which is a key technology that integrates construction and IT(Information Technology), has been rapidly introduced and expanded. Because BIM technology offers various benefits, countries that introduced BIM early has been actively promoted. However, misperceptions of BIM are prevalent in countries such as South Korea that have adopted it relatively late, with lack of awareness of its fundamental purposes. Under these circumstances, transparent and quantitative performance assessment needs to be executed in order to eliminate the misperceptions, and to explain and revitalize the BIM introduction. These quantitative performance measure KPI (Key Performance Indicators) to be measured should be prioritized. As derive performance indicators in terms of the four types (financial, customer, internal processes, learning and growth), and performance management systems, Uses the BSC to seek a balance between short-term financial goals, values and the value of long-term goals. Uses the BSC(Balanced Scorecards) to derive performance indicators in terms of the four types (financial, customer, internal processes, learning and growth), and performance management systems, seeking a balance between the value of short-term financial objectives and the value of long-term objectives. Through this, the KPI (Key Performance Indicators) which is used for measuring the effect of the BIM will be generated and also the method that can determine whether the generated KPI figures are objectively inter-connected will be suggested as well.

Aug 1, 2013

By D. McConchie

The use of Bauxsol? (physically and chemically modified alumina refinery residues) to treat acid rock drainage (ARD), and sulphidic waste rock and tailings, provides new options for managing some intractable environmental problems at both derelict and active mine sites. Treatment of ARD waters using the Bauxsol technology shows that the effectiveness of raw Bauxsol material can be enhanced by including modest amounts of selected industrial minerals or common chemical additives. The type and amount of additive required and the amount of the blend needed to treat the water depends on the initial composition of the water and the target water quality; for some ARD waters, optimum treatment may require one or more changes in the type or amount of additive used. Maximum treatment efficiency can be achieved only when a balance is maintained between the rate of trace metal binding and the rate of change in water pH; adding treatment reagents faster than can be accommodated by the reaction kinetics will not result in more rapid water treatment. This paper presents the results for treating several ARD waters to illustrate the importance of blend selection and treatment procedure. Although treating ARD water is often necessary, this strategy treats the symptoms rather than the cause. The best permanent solution is to treat the sulphidic waste rock or tailings such that they do not continue to oxidise and produce acidic metal-rich leachates; sulphide oxidation needs to be stopped or slowed to a rate that can be accommodated by normal environmental processes. Capping lined impoundments is not a solution because all caps and linings will inevitably fail some time in the future creating a nasty surprise for some future generation. Adding lime is also less than ideal because the lime leaches from the treated material; treatment often appears to be effective for a few years and then fails. Bauxsol technology offers effective alternatives to conventional liming and capping procedures and Bauxsol blend application rates and procedures can be planned to ensure that no acidic or metal-rich water can ever escape from the site. Bauxsol can be physically mixed with the sulphidic mine wastes or it can used to form subsurface permeable reactive barriers, or both. Bauxsol treated waste rock and tailings can be immediately and effectively revegetated. In this paper we present leachate quality and plant growth rate data for several sulphidic waste rock and tailings deposits treated using the new technology.

May 1, 2003

By A. C. Drost

The mining industry has been put under closer scrutiny in recent years, which has led to the adoption of a plethora of initiatives in countries around the world and by international organizations, some voluntary and others mandatory, governing economic, ethical, social and environmental practices of this industry. In order to plan appropriately, secure project financing, build value and manage risks, it is imperative to identify and understand the application of this new and evolving regime, which can be described under the general label of corporate social responsibility (?CSR?) law, and to incorporate compliance policies into the day-to-day operations of mining companies. Our paper and presentation will describe this new legal framework, which includes both ?soft? law and ?hard? law adopted at the international and domestic level that governs the actions of mining companies, particularly when operating in developing countries. While the notions of hard and soft law may seem abstract and grounded in legal theory, this paper shall demonstrate how these concepts concretely apply to companies in general, and to mining companies in particular. An analysis of the recent case law in this area as well as examples of corporate ?best practices? will illustrate the application of this body of law. As will be demonstrated through the case law, non-compliance of CSR law (both ?soft? law and ?hard? law) can lead to economic penalties, difficulties in accessing capital, loss of social licenses and even the withdrawal of permits and concessions. This confirms that now more than ever, ethics and sustainable practices in mining are fundamental to building a successful business model.

Aug 1, 2013

By P. J. Mackey, Elsie Kossatz

The small town of Bruce Mines lies a few miles east of Sault Ste. Marie, Ontario on the north shore of Lake Huron. This was the site of the first copper mine. This copper smelter used a reverberatory furnace, based on the Welsh process, and operated in the period of 1849 to 1850, when the plant was destroyed by fire. During the period of 1850 to about 1869, crushed and sorted ore was shipped to England and later to the United States. In 1869, a roastleach plant, based on the Henderson Process, was constructed at Bruce Mines and was operated until about 1872. This short article describes the early development of this historic operation. Although the rich copper ore found in the vicinity of Bruce Mines was known to the Indians, its discovery in or about 184 7 was credited to Mr. Keating, who named the area Bruce in honour of Lord Elgin (James Bruce), Canada's Governor General. In 1848, the property was acquired by the Montreal Mining Company for 40 000 pounds sterling and the company immediately sent a small party to investigate the deposit. The party sank a shaft on a lode within a hundred yards of the lake and also reported two adjacent lodes farther inland, which were left undeveloped until the turn of the century. Initially, the foundation of the headframe and hoist was built above the frost line and when the machinery was set in motion it collapsed. Eventually, the shaft was to reach a depth of 300 feet. By 1849, the property was well established and the small settlement consisted of 77 miners, 65 labourers, 4 boys, 11 tradesmen, including blacksmiths and carpenters, 2 mining captains, 1 engineer, 2 clerks and 1 superintendent. The community, including the workers' families, numbered about 250.

Jan 1, 1999