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By Navid Bahrani

Introduction ? Today?s economic market is motivating underground mining companies to increase development advance rates and enhance their NPVs. ? For example, block cave mining involves development of kilometers of drifts with multiple pillars. ? The cyclic nature of drill and blast, and its inherent tendency to damage the surrounding excavation rock mass and increase support demand often result in poor advance rates ? This has motivated mining companies to replace the conventional drill-and-blast as the main excavation method with alternative methods such as mechanized excavation. ? There is little experience with mechanized or non-explosive excavation methods in hard rock metalliferous underground mining.

Oct 1, 2010

By J. E. Udd, L. B. Geller

"Mine-shaft wire-rope discard regulations include, among other criteria, a limited amount of permissible loss-of-breaking-strength (LBS). Currently, this parameter is estimated on the basis of non-destrutive-testing (NDT) with electro-magnetic (EM) type instruments. This paper analyses the accuracy with which these estimates have, so far, been obtained in practice.It concludes that while certain types of testers have produced better results than others, the desired accuracy level has not been attained. Also discussed are the putative reasons for this situation, and appropriate actions that the mining industry might wish to take."

Jan 1, 1990

IDS: The Company IDS Ingegneria Dei Sistemi, founded in 1980, is a world leader as a high technology solution provider in selected niche defense and civil market sectors ? Private and Independent ? IDS?s Quality System is certified ISO 9001 Ed. 2000 ? IDS has the highest Military Clearance ? Continuously measure (24x7) mine wall movements with sub-millimetric accuracy at long distance (up to 4 Km) ? Provide reliable early warning for progressive slope movements potentially leading to mining wall failures ?Map the long term evolution of slow moving slopes to get a better knowledge of the rock mass strength

Aug 1, 2013

By David Nicholls

?Overview of New Afton ?Reserves and Resources ?Geology and Mineralization ?Exploration ?Capital Project Development to Date ?Mine Development ?Processing ?Construction ?LOM ?Health, Safety, Environment and Social Responsibility Overview of New Afton ?Fully owned by New Gold Inc ?Large gold-copper porphyry deposit, amenable to block cave mining, production commencing in 2012 -1 million ounce gold reserve -1 billion pound copper reserve -Estimated 13 year mine life ?Low operating cost ?Estimated capital expenditure requirements -Spend to date ?US$200million -Remaining to be spent ?US$400milllion ?Robust economics ?Excellent location and infrastructure ?Significant cash flow contributor for the Company

May 1, 2010

By Roxanne Scott

Outline ? Overview of Community Investment in the Mining Sector ? Emerging Good Practice: ?Strategic Integrated Community Investment? ? Assessing Local Context: ? Institutional Assessment ? Partnership Assessment Approaches to Community Investment Isolation: No proactive engagement in community development Ad hoc philanthropy: small infrastructure, sponsorships, donations Strategic philanthropy: Community proposes options for development Company decides what to do and carries it out, e.g. building schools, health posts, roads Strategic integrated community investment: ? Aligned with government/community development goals and priorities ? Communities and government involved in decisions and execution ? Focused on training and capacity building ? Partnerships ? Continuation in absence of company support Measured returns on investment

May 1, 2010

By B. McLaughlin

Agnico-Eagle started sinking the Penna Shaft in 1995 with a hoisting plant capable of hoisting 1800 t/d from a 2240 m deep shaft. Exploration success led to the installation of a hoisting plant capable of extracting 4500 t of ore and 1800 t of waste per day from a depth of 2210 m. The introduction of a new rope selection factor, permitting a safety factor of 4.0, represented the breakthrough required for a cost-effective project. This paper describes the process taken to introduce the new rope selection factor and its impact on the original plant.

Jan 1, 2004

By A. J. MacRae

Metallurgical furnaces are made up of complex multi-component systems that must function either together or in parallel for safe, and reliable operation. Thermal expansion of single material components experience induced stresses during heating and cooling, which can lead to cracking or failure. Multi component elements and systems can experience significant thermally induced stresses during both steady state and transient temperature conditions. Examples pertaining to temperature effects on refractory, copper cooling blocks, furnace shells, and complete systems will be discussed. The purpose of the paper is to highlight how stresses and strains are developed due to differential thermal expansion.

Jan 1, 2015

By Bill Mercer

The Triggers for PDAC Involvement in H&S ??Increase in serious accidents in mineral exploration in past few years ??Increasing junior role in exploration ?? Impression that there were few H&S protocols in place in smaller companies ??Lack of national benchmarking ?? The attitude that H&S is a provincial responsibility ??Corporate Social Responsibility initiative What is the issue in exploration? ??Mining?s reputation as ?dirty and dangerous? ??In public?s and media?s minds exploration employees are ?miners? ??In Canada, regulators often do not distinguish between ?exploration? and ?mining?. ??How does exploration compare to mining from a H&S point of view?

May 1, 2008

By D. D. Macdonald, G. Engelhardt

The accumulation of damage due to localized corrosion [pitting, stress corrosion cracking (SCC), corrosion fatigue (CF), crevice corrosion (CC), and erosion-corrosion (EC)] in complex industrial systems, such as power plants, refineries, desalination systems, etc., poses a threat to continued safe and economic operation, primarily because of the sudden, catastrophic nature of the resulting failures. Of particular interest in managing these forms of damage is the development of robust algorithms that can be used to predict the integrated damage as a function of time and as a function of the operating conditions of the system. Because complex systems of the same design rapidly become unique, due to differences in operating histories, and because failures are rare events, there is generally insufficient data on any given system to derive reliable empirical models that capture the impact of all (or even some) of the important independent variables. Accordingly, empirical models have generally failed to provide a robust basis for predicting the accumulation of corrosion damage in complex systems under realistic operating conditions. The alternative prediction philosophy is determinism, in which the development of damage is described in terms of valid, physico-electrochemical mechanisms with the output being constrained by the natural laws. The differential damage is then integrated along the corrosion evolutionary path for the system (i.e., over the future operating "history") to yield the desired integrated damage, which is the quantity that is most useful to an operator. In this paper, we review the theory of predicting corrosion damage within the framework of Damage Function Analysis (DFA), with particular emphasis on the pitting of aluminum in chloride solutions and on the accumulation of damage from SCC in Type 304 SS components in the primary coolant circuits of Boiling Water (Nuclear) Reactors (BWRs). These cases have been selected to illustrate the various phases through which localized corrosion damage occurs.

Jan 1, 2005

By L. Rodd, C. Walker, T. Koehler

"The energy content of slag represents approximately 80% of the total energy inputs to a laterite nickel electric smelting furnace. Conventional slag handling methods produce only low grade heat and the entire thermal content of the slag is wasted. A heat recovery system proven on BOF slag in the mid 1980's can be adapted to a laterite nickel rotary kiln electric furnace (RKEF) plant. Slag is granulated using a high velocity air jet inside a waste heat boiler to produce slag granules. Granules are cooled during flight via radiation to water-cooled boiler walls and by convection to the granulation air. This system has the potential to recover 80% of the total slag energy in the form of hot air and steam.Integration of the recovered slag energy into the RKEF smelter can be achieved by a number of methods, including the use of preheated air at the ore dryers, kiln or existing power plant. Energy from the slag boiler may be used to reheat boiler feed water from the power plant or to produce superheated steam and generate electricity. The heat recovery system can provide up to 25 - 30% of the total electrical requirement of each RKEF line and a reduction in CO2 emissions of 234,000 tonnes per year.The total cost of slag heat recovery, including CAPEX and OPEX, is $2.5/GJ, which is competitive with using coal when CO2 credits are $18 per tonne. With Clean Development Mechanism (CDM) carbon credits currently selling at €13 ($20 USD) per tonne CO2, there is considerable opportunity for slag producers in regions including South America, Korea, Indonesia and Africa. Increasing fuel costs and more wide-spread legislation for GHG emissions will likely create conditions in which slag heat recovery could generate a favourable return on investment."

Jan 1, 2010

By M. Nagamori, A. J. Plumpton

"Commercial HCl-leaching of magnesite and serpentine yields highly concentrated aqueous solutions containing 25 mass % to 33 mass % MgCl2. The partial molar enthalpies and heat capacities, the ionic activities of Mg2+ and Cl–, and the Raoultian activity of H2O have been assessed for the concentrated MgCl2-H2O solutions at temperatures of 348 to 373 K. These thermodynamic data are used to calculate the pH of aqueous MgCl2 solutions saturated with a Mg-bearing mineral such as magnesite, serpentine, brucite, forsterite, enstatite or talc. On the basis of these thermodynamic data, technico-economic aspects are discussed as to neutralization with pulverized MgCO3, water evaporation from the MgCl2 solutions, and ore composition including such minor constituents as CaCO3, FeCO3 and Fe3O4. IntroductionA major magnesium electrolytic reduction plant operates in Quebec, where another will begin its production in the year 2000. One uses imported magnesite ore as raw material, while the other will utilize local asbestos tailings (serpentine). Both processes produce a concentrated salt solution of 25 mass % to 33 mass % MgCl2 by leaching the ore with concentrated hydrochloric acid. Thus, the two processes differ mainly in the HCl-leach and related operations. After the HCl-leach of the ore, the serpentine process yields about 25 times more wet cake to filter and wash than the magnesite counterpart. A comparative cost-engineering study with respect to slurry filtration and cake washing has been published elsewhere (Blackburn and Nagamori, 1994). By contrast, the present study considers the thermodynamics and technicoeconomics of the HCl-leach itself for both ores."

Jan 1, 1999

By T. E. Morimoto

Summary The Research Council of Alberta has made a series of tests with the cyclone washer to investigate the influence of the following operating variables: underflow apex diameter, .specific gravity of medium, pulp ratio, density distribution of the feed, and size analysis of the feed. The results obtained for all the variables studied, except size analysis of the feed, are included in this paper. The tests were made with smaller underflow apex diameters and lower specific gravity .suspensions than have been recommended by Cerchar for the sharpest separations. However, what is considered to be sufficiently good cleaning was accomplished with a suspension of 1.30 specific gravity and an underflow to overflow diameter ratio of 0.56. It was found that the sharpness of separation was not affected appreciably by variations in specific gravity of suspension or underflow apex diameter provided that the density of separation was within the normal range of washery operation. Cyclone performance was not too adversely affected by decreasing the pulp ratio. The minimum figure which gave reasonable separation was 4 to 1. The tests with various density distributions of feed revealed .that the degree of washing difficulty had no detrimental effect on the .sharpness of separation given by the cyclone. Introduction A major problem of the bituminous coal industry today is that of reducing the ash content of the finer sizes (minus 1/4-inch) of coal. This problem is particularly acute in Alberta, where, because of tectonic movement subsequent to deposition, the coals have been rendered friable, and bands of impurities have been intimately mixed with the clean material. As a consequence, most Alberta coals, as mined, contain a large proportion of fines and have a high inherent mineral-matter content. The advent of mechanized mining and stripping operations ?has further aggravated this problem.

Jan 1, 1952

By F. Vasilikou

Commercial deployment of Carbon Capture Utilization and Storage (CCUS) requires field testing of a scale that can stress the geologic reservoirs. One such reservoir of interest consists of unminable coal seams that exhibit favorable characteristics and depositional environments and lower pressure and temperature than other, deeper, reservoirs. Such conditions can reduce compression costs while utilizing the action of adsorption that offers a more effective carbon dioxide (CO2) bonding than free storage or solution. To ensure the success of such tests, a number of parameters should be accurately determined, such as the seam geometry and stratigraphy, coal porosity and permeability parameters as well as optimum injection conditions. In essence the CO2 injection model should be calibrated for the reservoir characteristics using all available data. History matching calibrations are based on gas and water production from existing wells prior to injection. This paper will present reservoir models that were developed for a pilot--scale 907 tonnes (1000 tons) CO2 injection test that was performed in 2009 through one legacy coalbed methane production well in Russell County, Virginia, USA. The model incorporates a number of individual coal seams about 0.3 m (1ft) in thickness located at depths ranging from 300 to 700 m (1,000 to 2,200 feet). Model calibration was performed through history matching to prior production data, and subsequently the model was utilized to develop different injection scenarios. The developed model was used after injection to calculate CO2 plume distribution patterns that were monitored at the injection test. The paper will present model data and assumptions with a special emphasis on the effect of hydraulic fractures and the skin factor to the coalbed methane (CBM) production model.

Aug 1, 2013

By Thomas G. Madgwick

Introduction Development of oil and gas is still centred in the Province of Alberta, much as it was when C. C. Ross read a paper on this subject three years ago at the Annual General Meeting in Montreal; but so far as gas is concerned, its early production in Saskatchewan seems now assured. The three years that have elapsed since Mr. Ross' paper have witnessed a growth in the world's production of oil that has created a potential supply out of all proportion to the demand for petroleum products, and one that has resisted the most energetic efforts of the industry entirely to control. The natural result has been very much to retard the active prospecting of new structures in the Prairie Provinces with any immediate view to oil production, although the same factor has not hindered the search for gas to the same extent. One consequence has been to divert the attention of organized oil operators from wildcat drilling to more detailed geological investigation than had hitherto been customary, sometimes accompanied by test drilling with a view to the elucidation of geological structure rather than to the immediate development of production which at the present is not needed. Nevertheless, in spite of the growth of this phase of oil prospecting - which the writer would be the last not to welcome as a very real blessing and of far greater value than indiscriminate wildcat drilling in either the complex structures of the foothills or the simpler but largely concealed formations of the plains- it is most satisfactory to have to record that in these three years the growth of production both of naphtha and the heavier crude-oil has kept pace with the by no means inconsiderable growth in the production and utilization of natural gas.

Jan 1, 1929

By I. Haskett

ABSTRACT The Redwater pool, in north-central Alberta, was discovered in October, 1948, and at the end of 1950 was about 85 per cent developed. Production is from a Devonian coral limestone reef and is found at an average depth of 3,150 feet. The pool has an estimated .productive area of 37,000 acres, and a maximum oil zone thickness of slightly over 200 feet. Wide variations exist in both type and values of porosity, with the average value determined for the reservoir being 6.16 per cent. The total stock tank oil in place is about 1.24 billion barrels. The crude has a saturation pressure of 485 psig, com-pared to the original value of 1,050 psig for the reservoir, and the principal recovery mechanism so far has been the natural water drive. Cumulative production to January 1st, 1951, has been about 15.5 million barrels. These withdrawals resulted in a reservoir pressure decline of slightly over 100 psi. Predictions of future behaviour indicate that the water drive will not be of sufficient magnitude to maintain the reservoir above saturation pressure past 1953, and that, with natural depletion, the pool will be produced largely by a solution gas drive. Pressure maintenance by water injection has been considered and the possibility of raising the pressure to the original value of 1,050 psig is also discussed. INTRODUCTION WITH the discovery of the Lewduc pool, early in 1947, the Devonian limestone became the major geological formation contributing to Western Canada's rapidly growing petroleum reserves. Redwater, discovered in October, 1948, is now the largest known Devonian pool in Canada, with a recoverable reserve estimated at approximately 500 million barrels. Until recent years, the knowledge of the nature and characteristics of this type of limestone reservoir has been comparatively limited.

Jan 1, 1951

By The Mill Staff

"IntroductionCOMMENCEMENT of operations at the new No. 7 shaft and 10,000-ton mill at Creighton mine was a major step in the programme of conversion to all-underground mining by the International Nickel Company of Canada, Limited. Planned ten years ago, the orderly transition has been greatly speeded-up to offset the heavy drain on production imposed by World War II and also to meet the increased demand for nickel caused by the current international situation. Development of new mining methods, and process changes in the reduction plants, have made possible the economic recovery and utilization of ore of lower grade than formerly used and of varying metallurgical characteristics. By 1953, when the Company's open-pit mining operations are scheduled for completion, the hoisting capacity of its five underground mines in the Sudbury district will have been increased to 13,000,000 tons per year, compared with 5,700,000 tons of underground ore hoisted in 1950.Two types of ore occur at Creighton. One is a breccia and stringer type that contains a high percent-age of massive sulphides and is located in sheets along shears and in large and small pockets on the underside of the main norite mass; the other type, forming the main part of the ore zone, is mineralized norite that occurs as a •sheet up to 400 feet thick overlying tl1e breccia ore. In both types of ore the minerals of economic interest are pentlandite, which is intimately associated with pyrrhotite, and chalcopyrite. Early mining was confined to the breccia ore; this ore was mined by open stoping methods. The hanging-wall was later allowed to cave, with the result that the old stopes are now filled with caved low-grade ore."

Jan 1, 1952

By G. M. Furnival

A PROGRAMME of structure drilling was commenced in the Southern Alberta Plains in June, 1943, for the purpose of determining the geological structure of the underlying sediments. More than 270 holes have been drilled throughout an area of some 1,800 square miles or 1,000,000 acres (see Figure 1). The Southern Plains of Alberta are covered by a mantle of glacial drift,' at places exceeding 200 feet in thickness. Only where this mantle has been dissected by deep drainage channels is bed-rock exposed to any great extent. Along such channels, surface geological mapping can be conducted to ad- vantage. Accordingly, geological mapping was commenced _in 1942 and continued each season to the present. To supplement this information, a survey of the water wells was carried on in conjunction with the mapping. However, to obtain more positive and evenly distributed structural control throughout the area as a whole and to define more adequately structural trends indicated by the preliminary mapping, it was necessary to resort to the use of drills to penetrate the glacial mantle. Various types of light drills are commonly used for this purpose and provide geological information in the form of drill cuttings, cores, drilling time rates, etc. Correlation of information is generally obtained through comparison of cored sections, drill cuttings, micro-fossils, and drilling time rates. However, in this case the holes were electrologged and correlations were made chiefly by comparison of such logs. The data so obtained is plotted and portrayed in the form of structure contour maps on recognizable stratigraphic horizons and in the form of isopach maps of the recognizable stratigraphic intervals penetrated in the holes. This method had not been widely used in Alberta previously and the technique employed was necessarily developed after the project began.

Jan 1, 1945

By Ye Chen, Jianhua Chen, Xianhao Long, Qingxia Liu, Zhenghe Xu

"It is crucial to understand the mechanism of the collector interacting with the mineral surface in the presence of water molecules, which could influence the relaxation and electronic properties of sulphide mineral surface due to the proximity effect for narrow band gap of semiconductors. The adsorptions of three typical collector molecules (xanthate, dithiocarbamate and dithiophosphate) on the sulphide mineral surfaces in the absence and presence of water molecule have been simulated by density-functional theory (DFT). The calculated results show that the adsorptions of collectors on clean mineral surface in vacuum are not in agreement with the observed flotation behaviours. The presence of water molecules has a great influence on the adsorption of collectors. The analysis of density of states of the mineral surface atom suggests that the adsorption of water molecules could influence the electronic properties of mineral surface and consequently influence the adsorption between the surface and the collector molecule.INTRODUCTIONIn the separation of multi-metal sulphide ores, the selectivity of a collector is a key factor for the efficient recovery of the aimed mineral. Xanthate, dithiocarbamate (DTC) and dithiophosphate (DTP) are the most common collectors used in the flotation of sulfide minerals. Generally, xanthate exhibits powerful collecting property but lack of selectivity. While dithiophosphate and dithiocarbamate show the good selectivity in the lead and copper sulphide mineral flotation. The mechanisms of these collectors interacting with the sulphide mineral had been attracted many attentions and several mechanism based on experimental results had been reported (Chander & Fuerstenau, 1974; Fuerstenau, 1990; Raju & Forsling, 1991; Crozier, 1991; Bradshaw, Cruywagen & O’Connor, 1995; Guler, Hicyilmaz, Gokagac & Emekci, 2006). However, the micro-mechanisms of the selectivity of these three thiol collectors on different sulphide mineral surfaces are not fully understood."

Jan 1, 2016

By S. Xu

Magnesium alloy AM50 is of interest to automotive cradle application because of it excellent castability and good ductility. In this work, microstructure and mechanical properties of both low pressure die cast (LPDC) and high pressure die cast (HPDC) AM50 test bars are characterized. Microstructure was examined using optical microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). Phase identifications were performed using energy dispersive x-ray spectrometer (EDS) and TEM diffraction. It has been found that LPDC produces much coarser microstructure than HPDC. At the same time, the HPDC samples are more heterogeneous in microstructure and composition close to grain boundaries. Particles with various dimensions and morphologies of two different intermetallic phases, Mg17A112 and A18Mn5, were found in all the samples. Mechanical tests were performed under conditions similar to those related to an engine cradle application. LPDC samples show lower strength but better creep resistance than HPDC mainly due to the difference in grain sizes and grain boundary microstructure between LPDC and HPDC. Creep curves are well described by the empirical Andrade equation. Tensile-compressive yield and creep asymmetries were found in AM50, i.e. better deformation resistance in tension than in compression. The average yield asymmetry ratio for all the samples is 0.87. Microstructural examinations on the samples tested in tension, compression and creep showed that the deformation mechanisms in AM50 were slip plus twining at temperatures up to 125°C. The examinations indicate the important role of twining in the asymmetry phenomenon. The creep results indicate that dynamic precipitation of the Mg17A112 phase during testing is not the mechanism directly responsible for the creep asymmetry in AM50.

Jan 1, 2004

By R. Holmestad, M. Gazizov, S. Wenner, R. Kaibyshev, J. K. Sunde

"Mechanical properties and microstructure of an Al-4.7Cu-0.74Mg-0.51Si-0.48Mn-0.10Cr-0.09Ti-0.02Fe (wt. %) alloy subjected to various thermomechanical processing (TMP) have been investigated and compared to conventional ageing at 170°C (designated T6). Three TMP routes involving cold deformation of solution treated samples were tested. These were (i) 3%-stretching (T8-3%), (ii) equal-channel angular pressing (ECAP) to true strain (e) of ~1 (T8-1) and (iii) ECAP to e~2 (T8-2), all with subsequent ageing at 170°C for 0-96 h. At peak age conditions, both yield stress, ultimate tensile strength and elongation-to-fracture decreased for the T8-3% state as compared to the T6 condition. Intermediate ECAP (T8-1 and T8-2) lead to significant increase in maximum yield stress, ultimate tensile strength and elongation-to-fracture. The changes in mechanical properties were related to microstructure evolution, encompassing changes in grain sizes, dislocation densities, precipitate morphology and phase fractions, which were characterised using transmission electron microscopy. Relations between TMP, precipitation behavior and contributions to different strengthening mechanisms are evaluated.INTRODUCTION Al-Cu-Mg-Si alloys are widely used as structural materials in aerospace industry due to their attractive combination of high specific strength, good fracture toughness and enhanced creep resistance. These properties are largely due to the formation of a large number of nano-sized metastable precipitates during artificial ageing (Polmear, 2006; Eskin, 2003; Gazizov, Dubina, Zhemchuzhnikova, & Kaibyshev, 2015). The precipitation behaviour in these alloys is complicated and depends among other things on Cu concentration and the Mg:Si ratio (Wolverton, 2001; Chakrabarti, & Laughlin, 2004). In general, the precipitation sequence has been presented in a prior study (Eskin, 2003) as follows:"

Jan 1, 2018