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By P. V. Golde, R. A. Poole, G. R. Baiden

"The results being presented in this paper are those obtained during 1996 on a drilling automation project at Stobie mine. This project has successfully demonstrated that the remote operation of multiple drills (by a single driller) from surface using Tamrock Data Solo 1000 Sixty drillrigs is technically feasible and can potentially bring significant rewards in terms of productivity and work environment improvements, as well as labour and maintenance savings. BackgroundThe ObjectiveThis paper is an update of a previous report on remote drilling research at Stobie mine. Enabled by the communications system installed at the mine, the ability to remotely control underground equipment from surface has been demonstrated (Poole et al., 1996). This paper discusses the needs and process required to carry this concept to consolidate the operation of multiple machines under a single operator.The TeamThe team assembled to develop and implement the automation and the communi-cations extensions needed to allow the multiple machines’ operation from the surface by one operator included the following:INCO Mines Research supplied the project management and original project initiative. The primary purpose was to prove the advantages of savings associated with the driller not being required to travel to the underground drill location coupled with the savings associated with one-man, multiple-machine techniques.Tamrock EJC supplied the Data Solo 1000 Sixty drills and the Tamrock specific machine-based custom software. The drills were produced in Finland with no provision for remote operation of the drill from other than the umbilical attached local console.Automated Mining Systems supplied the modifications to the drill communications equipment to allow the machine communications to become broadband compatible. As well, Automated Mining Systems also supplied the hardware necessary to be able to remotely control the portable video camera, as well as the data logging equipment.Stobie Mine personnel were made available to test the function and then integrate the concept of remote control drilling into the Stobie operations."

Jan 1, 1997

By B. K. Bhattacharyya, Morley. L. W.

"The primary purpose of conducting aeromagnetic surveys in mineral areas, and interpreting the data thus obtained, is to aid in the extrapolation of the geology from known to unknown areas-both in a horizontal and vertical direction. This paper describes one of the steps in the process of interpretation which has, in the past, been neglected-that of mathematically or quantitatively treating the data in two-dimensional map form. For this, several techniques are available.These techniques determine the downward and up-ward continuation fields, the second vertical derivatives and the fields reduced to the pole from the total magnetic field data. Second vertical derivatives and downward continuation fields increase the resolution and sharpness in the observed magnetic anomalies and tend to outline the surface traces of causative bodies with a reasonable amount of success in most cases. The 'reduction to the pole' is a mathematical process of calculating the field at the north pole from the observed field so that the un-desirable effects of the dip and declination of the earth's field and of rock magnetization are eliminated.New and accurate means of carrying out these calculations have been developed by the Geological Survey of Canada. In this paper are also presented the results of a method for obtaining the symbol and numerical map of the processed data with the help of the printer associated with the computer. The tedious work of digitizing magnetic field values in a map can be speeded up by the use of a semi-automatic coordinatograph, with the aid of which field values can be accurately transferred to punched cards."

Jan 1, 1966

By L. Paulino, C. E. Zangiacomi, J. Yamamoto

"This paper presents the learning from Alcoa Po9os de Caldas Smelter in Brazil, after several energy restrictions resulting from the failures of three rectifier units at its power switchyard. Starting on December 27th, fuses and diodes failed in three rectifier units of Potline #1, causing a long and dangerous power interruption. Even after current was reestablished, amperage was only 70% of the line target leading to a bath freezing process that lasted for around 48 hours. The process engineering team played with several potroom parameters as pot resistance, bath and metal levels, alumina feeding and bath chemistry in an attempt to minimize impact on the potline metal output and energy consumption. As it will be illustrated, the first battle was to keep the pots running on a ""survival"" approach. After that, several changes took place on the procedures used to run at reduced current which were considered rather successful. Finally, some recommendations will be given to foresee and prevent transformers and rectifiers from undesirable failures."

Jan 1, 2006

By F. H. Samuel, H. Tahiri, S. Valtierra, H. W. Doty, A. M. Samuel

L'affinage des grains dans les alliages d'aluminium consiste à augmenter le nombre de sites de cristallisation de la phase a-Al afin d'obtenir une structure fine. Les alliages mères de type Al-Ti-B sont largement utilisés comme raffineurs des grains. Cette étude a pour but d'établir des mécanismes convenables d'affinage des grains dans l'alliage A356 en utilisant cinq alliages mères et deux températures de coulée (750°C et 950°C). Les résultats montrent que la phase a-Al prend une forme selon l'alliage mère ajoute; les échantillons coules a haute température montrent une taille de grain plus grosse; les températures de germination et de croissance augmentent avec I' augmentation du Ti ou du B et la taille des grains diminue. L'alliage mère Al-4%B montre une puissance remarquable en comparaison d'autres alliages mères. Pour cet alliage mère, le titane résiduel dans l'alliage A356 réagit avec le bore pour former TiB2 qui, par la suite, agit comme un germe actif pour la phase a-Al.

Jan 1, 2006

By S. J. Laskowski

In potash ore flotation, carried out in NaCI-KCI saturated brine (about 6-7 molar KC1 and NaCI solution), long-chain primary amines are used as flotation collectors. Long-chain primary amines are poorly soluble in water and their solubility further decreases at high electrolyte concentration. For ionic surfactants there is a characteristic temperature (Krafft Point, KP) below which their solubility is too low for micellization. In a previous study, the effect of pH on the KP of dodecylammonium chloride in water was determined [Q. Dai and J.S. Laskowski, Langmuir, 7, 1361-1365 (1991)]. This paper deals with the effect of electrolyte concentration on the KP of dodecylammonium chloride. The derived theoretical relationship between the KP and the critical micelle concentration (CMC) for dodecylamine can be used to calculate the KP for electrolyte concentrations of up to 0.5 mol/L (about 8% NaCI-KCI brine). A simple experimental procedure for the determination of the KP for higher electrolyte concentrations is also described. The results show that the Krafft point of dodecylamine increases from about 17-18°C (in distilled water) to about 80°C at 16% brine saturation.

Jan 1, 2006

By J. Schmidt

The development of set of laboratory experiments, intended to help undergraduate students meet Canadian Engineering Accreditation Board requirements for Engineering Design outcomes, is described.The laboratory, which is part of a third year level course in hydrometallurgy, is aimed at advancing the ability of students to generate and use experimental results to design an industrial copper leach/SX/EW plant. Emphasis is placed on the students demonstrating the ability to use of their engineering knowledge in weighing the pros and cons of the various process options that they test in converging to a final flowsheet. INTRODUCTION Over the past number of years the Canadian Engineering Accreditation Board, CEAB, has dramatically shifted the way that they evaluate undergraduate programs. In the past, the focus was on measuring of the quantity and quality of material the students were intended to learn as well as the methods and resources used to deliver that material. Now, rather than principally evaluating the inputs of programs, the focus is more on measuring the quality of the outputs from the programs, i.e. the quality of graduating students. In this regard, the CEAB has developed a list of twelve attributes that learners must develop in the course of their studies. Engineering programs must, not only demonstrate that their curriculums provide opportunities to develop these attributes, but must measure student proficiency in each of these attributes as they progress toward graduation. One particular graduate attribute that Laurentian University’s Bharti School of Engineering has encouraged its faculty members to develop content for is “design”. Engineering Canada (2018) defines this attribute as “an ability to design solutions for complex, open-ended engineering problems and to design systems, components or processes that meet specified needs with appropriate attention to health and safety risks, applicable standards, and economic, environmental, cultural and societal considerations”. The previous laboratory component for the hydrometallurgy course was a collection of unconnected experiments covering leaching, solvent extraction, ion exchange, and electrowinning. Like in other undergraduate courses, students would perform stand-alone experiments, make the specified measurements, do the specified analyses of the results, and report the findings, all as strictly detailed in the lab manual. The vision for the new lab was to create an experience that would more closely mimic an industrial research program whereby students would start with a given feed material and would progress through a series of connected experiments. Emphasis is placed on the student demonstrating competency in, not only, generating and analyzing experimental data, but also in using the data along with their engineering knowledge to design and evaluate the pros and cons various plant configuration options. Principally, students are asked to weigh cost, safety, and environmental concerns in converging to their final flowsheet. In designed the leach circuit, students must weigh the costs/benefits of varying leach temperature. Higher leach temperatures will yield faster and more complete copper dissolution, which will allow for the specification of relatively smaller leaching circuits, saving capital costs. However, hotter acid solutions are more dangerous to handle and require increasing amounts of energy to heat the slurry, increasing operating costs. In solid/liquid separation, students must weigh the pros and cons of the addition of a flocculent to assist settling. The flocculant will allow for the design of a thickener circuit that employs units with a relatively smaller area, but will result in a thickener underflow with a lower pulp density, which may necessitate a larger number of thickeners. In addition, the environmental concerns of producing a tailings product that contains an organic contaminant should be addressed. In solvent extraction, students must specify the number of stages of loading and stripping, as well as organic and aqueous flowrates to produce suitable raffinate and rich electrolyte streams. Finally, in electrowinning, students will compare the costs/benefits and risks of the use of precious metal coated titanium dimensionally stable anodes (DSAs) versus conventional Pb based anodes.

Jan 1, 2019

By A. M. Brown, P. V. Straznicky

Dimpling as a means of flush countersinking rivets is an old process predominantly used in secondary structures. The introduction of GLARE as an aerospace material has renewed interest in dimpling and its possible application in primary structures. The dimpling process is able to prevent the creation of a machined knife-edge in the thin aluminum plies of the GLARE sheets. In addition, dimpling eliminates the need to use reduced height rivets, such as the NAS 1097 rivet style. This investigation expands on an earlier study into dimpling of GLARE by Rans and Straznicky. In order to tailor the dimpling process to GLARE, FEM simulations were developed. After verification, a study was performed to find the best parameters for dimpling GLARE3-2/l. Coupon fatigue tests were carried out and the dimpled joints demonstrated increased fatigue lives over the conventional machine countersunk joints. Future wide panel fatigue tests are planned to confirm the usefulness of dimpling thin GLARE laminates.

Jan 1, 2006

By Ainul Akhtar, Steve Cockcroft, Jixiang Xu, Daan Maijer, Lu Yao

"Nitrogen rich Ti-N inclusions are one of the more difficult inclusions to remove during liquid metal refining of titanium. If present in the final component, they can significantly decrease the mechanical performance of titanium and its alloys in applications involving cyclic loading. Understanding the kinetics of dissolution of Ti-N particles during consolidation/melting of titanium can help us better operate and design the melting processes to minimize their occurrence in Premium Quality Titanium production. A numerical model based on finite difference method has been developed to calculate the dissolution of a spherical Ti-N particles in molten titanium. Analytical solutions were used to verify the finite difference code for calculation of concentration profile and the dissolution of spherical solids. Taking into account the limitations in these approaches for the different cases examined, the invariant field approximation showed good agreement with the results from the numerical analysis. Evolution of the size of a spherical Ti-N particle during dissolution was predicted by the numerical model and the particle dissolves in 163 s.INTRODUCTION Properties like low density, high specific strength and excellent corrosion resistance make titanium attractive for a variety of applications. Key characteristics in the processing of titanium and its alloys include its high sensitivity to impurities, especially atmospheric oxygen and nitrogen and its high reactivity in the molten state. Nitrogen rich inclusions Ti-N, also known as Type ? or hard alpha defects, usually have substantially higher hardness and lower ductility than the surrounding material. Because they can act as fatigue initiation sites, Ti-N inclusions can significantly decrease the mechanical performance of titanium and its alloys in applications involving cyclic loading, even in minor amounts (tenth of a percent) (Lampman, 1990; Moiseyev, 2005; Lütjering & Williams, 2007). Ti-N encompasses as a broad range of nitrogen contents from a few wt% up to stoichiometric TiN. The liquidus temperature of Ti-N titanium increases substantially with increasing nitrogen content. Consequently, depending on the concentration of nitrogen, the melting point of Ti-N inclusions can be above bulk liquid metal temperatures during melt processing. Thus, removal of Ti-N defects hinges on dissolution and not melting."

Jan 1, 2017

By L. M. Dwarkin

Strip mining in Western Canada, though of considerable importance, is a fairly recent development for many of the operators in the district. Adding to the difficulty of unfamiliarity is the fact that a great deal of the stripping is done on pitching seams, for which the engineering and economic principles of setting the most advantageous strip ratio are not readily apparent. The novelty of the operation combined with the complexity of the principles involved can easily lead to misconceptions as to the determination of the economic ratio. Definition of Strip Ration There are two commonly accepted meanings of the term strip ratio: (1) The ratio of feet of overburden to be stripped per foot of coal recoverable. (2) The ratio of cubic yards of overburden per cubic yard or ton of coal. The first definition is inapplicable to pitching seams so, throughout this paper, strip ratio will be taken as the ratio of cubic yards of overburden to be removed per cubic yard of coal recoverable. Economic Ratio In the case of flat seams, the strip ratio is fixed by existing natural conditions, and the magnitude of this ratio determines whether stripping is economically feasible. With pitching seams, however, the strip ratio is a variable. On the outcrop, there is usually some coal which can be obtained with little or no stripping. As the work is carried down the pitch of the coal seam, the proportion of overburden continually increases until a point is reached where it is no longer economical to continue the operation. The question immediately arises as to the location of this point, and this resolves into the problem of determining the most favourable strip ratio, or, to use the accepted term, the economic ratio.

Jan 1, 1949

By Michael T. McCaffrey

The wide range of potential feed materials, process steps, and products in metallurgical facilities means that standard equipment might not be available to adequately meet the project technical and economic needs. Custom designed equipment should be considered only after rigorous research precludes purchasing standard equipment. However, the decision to use custom equipment introduces a new element of risk into the project. To manage the risk, custom equipment design should be developed through the same front end loading (FEL) phases as project development. If more than incremental development of custom equipment is required, appropriate test work or pilot trials are required to test key uncertainties. Important activities during custom equipment design include maintaining clearly defined performance objectives, conducting appropriate reviews, carefully crafting commercial and intellectual property agreements with design and fabrication partners, and assembling a multidisciplinary team with sufficient development expertise.

Jan 1, 2015

By K. Yamaguchi

"This Precious metals content copper scrap is treated with a copper smelting process, and copper and precious metals are recovered. The precious metal lost in the slag is increasing with increasing of treated scrap amount. To determine the portion of the precious metals chemically dissolved and that associated with the mechanically trapped matte in the slag will be a key factor to improve the recovery of those metals. The distribution of precious metals between copper matte and FeOx-SiO2 slag phases is determined at 1300 oC and a fixed partial pressure of SO2 of 0.1 atm for the matte grades from 40 to 70 mass% of copper. The distribution ratios show a tendency to increase when the grade of matte is increased. In addition, the solubility of platinum and rhodium in the FeOx-SiO2-CaO slag under the air and the solubility of platinum in the FeOx-SiO2 slag equilibrated with a pure platinum or the Pt-Cu alloy were determined at 1300oC in the range of oxygen partial pressure from 10-9 to 10-7. The solubility of platinum and rhodium in the slag tends to increase with increasing content of copper in the slag and oxygen partial pressure. INTRODUCTIONThe stringency of the supply and demand of platinum group metal (PGM) intensifies by localization for resources and increase of the demand for PGM, furthermore, smelting and the recycling of PGM in the nonferrous smelting process take an important role. Scrap containing a precious metal for the purpose of collection of PGM is treated by copper smelting recently. With increase of the treatment amounts, loss of PGM in slags is the serious problem.In considering of PGM loss in slags, knowledge of the distribution behavior for PGM between slag and matte phases or slag and copper phases and the PGM solubility in slags is important. The distribution ratios of silver and gold between the FeOx-SiO2 slag and the Fe-Cu matte were reported by Roghani (Roghani et al., 2000), Shinha (Shinha et al., 1985) and Takeda (Takeda et al., 1993) However, there is no data for the PGM distribution ratio. On the other hand, the PGM solubility in slags was reported by Sano (Sano et al., 1997) However, there is very few report for the solubility of PGM in the nonferrous smelting slags."

Jan 1, 2012

By F. P. Hassani, J. F. Boily, A. M. O. Mohamed, M. Hossein

The optimal geochemical parameters required to form ellringite in a lime-remediated site have been investigated with the use of thermodynamic modelling. The speciation of sulphate and 10 metals analyzed in samples of a mine tailing from northern Quebec was calculated with a computer model. The model also includes calcium, which would result from the addition of lime to the system. Two speciation calculations were done. The first one is a hypothetical speciation before the onset of precipitation and was used to devise the stability fields of minerals susceptible of forming in high pHs. The stability fields were determined by building activity ratio diagrams with sulphate, aluminum and calcium species concentrations for pHs ranging from 4 to 14. The investigation was carried out for a 25°C solution with an ionic strength less than 0.12. Thermodynamics predict that an optimal stability field for ettringite in the mine tailing samples containing 10-3 mol/L SO4-2,10-2 mol/L of AI(OH)4 requires at least 10-2mol/L of Ca+2 and a pH larger than 11.6. The sulphate contents of the mine tailing samples, however, limit the precipitation of ettringite and monosulphate could be an end-precipitate. The second speciation is in equilibrium with precipitates and provides information on the speciation of the residual metals. If ellringite could be precipitated as a stable form, it could serve as a sorptive agent for residual metals, and, due to its binding properties, consolidate tailings.

Jan 1, 1995

As land resources decrease, commodity prices increase, and technology evolves, deep sea mining is becoming a viable alternative to meet the increasing demand for minerals. Successful deep sea mining operations are built on sound identification of the resource, proper selection of equipment, a thoughtful production plan, and good project management. These four key activities can be further optimized by analyzing how the spatial variability and uncertainty of the ore body properties impact the final mining operation. To address this problem, IHC Merwede is in the process of developing a risk quantification framework in the context of deep sea mining, which makes use of state of the art geostatistical simulation methods and transfer functions to quantify geological uncertainty and translate it into decision or project risk. The paper introduces the Local Average Subdivision method (LAS) for generating simulated models of the deposit and presents a new extension to incorporate point measurements of geotechnical or ore grade properties. Due to its computational efficiency, the presented method is suitable for simulating largely extended sea floor deposits. The second part of the paper illustrates, through example case studies, the significant benefits of a risk based approach which translates geological uncertainty into financial or operational performance indicators. In particular, the focus is on assessing financial project risk and on the design optimization of the deep sea excavation equipment by analyzing cutting forces, specific energies, and power requirements.

Aug 1, 2013

By R. Glenn Madill

Western Canada is defined, for the purposes of this paper, as that part of the Dominion bounded approximately by the 95th and 141st meridians of longitude and the 49th and 80th parallels of latitude. It is comprised of Manitoba, Saskatchewan, Alberta, British Columbia, Yukon, and that portion of the Northwest Territories lying to the west of the 95th. meridian. The first magnetic observations made in Western Canada were in the interests of navigation by sea. Observations were made by Captain Middleton in Hudson bay at Churchill and York Factory in 1725, and along the Pacific coast by Captain Cook in 1778 and Captain Vancouver in 1792. The first systematic magnetic survey in Western Canada was made between 1819 and 1826 by Sir John Franklin in his widely distributed explorations. It is of interest to find that while the first magnetic declination observations made in Hudson bay and along the Pacific coast were purely in the interests of navigation, the next investigations, which were made in the Western Arctic, included measurements of inclination and force with those of declination. There was a valid reason for this more complete research into the magnetic field as the construction of declination charts depended on the position of the north magnetic pole. Halley promulgated a theory 1683 that " the globe of the Earth may be regarded as one great magnet, having four magnetic poles, two of them near each pole of the equator, and that in those parts of the world which lie near any of those magnetic poles the needle is chiefly governed thereby, the nearest pole being always predominate over the more remote" . The position of a magnetic pole may be defined as a point where the inclination is 90 degrees and the horizontal force zero. It is obvious that the position cannot be' defined by declination observations alone since, for some distance from the magnetic pole, .the horizontal force is too weak to give directive force sufficient to effect the pointing of a compass.

Jan 1, 1948

By J. A. Irvine

In 1972, a cooperative program to map and estimate the quantity of Tertiary coal resources in southern Saskatchewan was initiated by the federal and Saskatchewan governments. More than 700 exploratory boreholes were drilled over a two-year period, and data were obtained from other organization s on an additional 1500 boreholes in the area. Stratigraphic data and data on each coal seam penetrated in the boreholes, along with technical and location data for each borehole, were stored in a computer data base for convenience of retrieval, modification and manipulation. Programs and program packages were developed or adapted to: (1) select borehole information defined by variable retrieval parameters from the data base; (2) calculate derived information , such as overburden ratios. cumulative net coal thicknesses , mean weighted center of gravity of coal seams in each borehole, etc., from the selected data ; (3) produce posting maps of either selected data or calculated information in various combinations at variable scales on a plotter or CRT display; (4) produce contoured structure, isopach or ratio maps , and perspective diagrams as appropriate , utilizing plotter or CRT display; (5) calculate and categorize quantities of coal in place within user- defined "mineability-economic-reliability" limits. The emphasis in computer utilization was placed on geological credibility of the results and ease of operation by relatively untrained geological personnel, resulting in extensive use of interactive methods. The single most important benefit derived from using computer-assisted procedures is the ability to produce new maps and quantity estimates rapidly and inexpensively as a result of availability of new data or/and changes in external criteria which impose economic or mineability constraints.

Jan 1, 1978

By E. S. Allen, P. R. Kruesi, J. L. Lake

An electrochemical process is described for converting concentrates of base-metal sulphides to the corresponding pure metals and elemental sulphur. The application of the process to chalcopyrite is discussed. The process is also of potential interest in processing copper-nickel sulphides, and laboratory data concerning this potential are presented. The process creates neither air nor water pollution.

Jan 1, 1973

By Douglas R. Piteau

"Assessing the stability of a slope cut in rock is basically a problem of engineering geology - geology, because it involves a sound understanding of the important aspects of geology, such as geological structure, ground water, weathering and other natural phenomena, which all relate to or exist in a geological environment, and engineering, in that quantitative evaluations and calculations are necessary, these being based on mechanics and relating to the strength of the geological materials and the forces causing instability of the slopes. The engineering geologist must make every attempt to. provide, in a quantitative way, information on those geological factors which are necessary for making calculations of the probable stability of the slope. These include numerical assessments of quantities relating to the characteristics of structural discontinuities, rock types, topography, hydrogeology, tectonic history and other environmental factors. Based on the development and extension of these general principles, both preliminary and final slope stability studies of some open pits in South Africa, Swaziland and Zambia have been conducted. Some of the basic concepts and techniques developed to carry these studies out are described."

Jan 1, 1972

By M. Mahfoud

The effect of grain refinement on the tensile and fatigue crack propagation behavior of sand cast magnesium alloy AM60B has been investigated in the present study, C2Cl6 in the amount of 0,3% was used to grain refine the melt, The fracture toughness tests were conducted in laboratory air at room temperature (25°C) using a sine-wave cyclic frequency of 20Hz and a load ratio of R = 0,1, The response in the Paris's regime and the critical stress range were determined, Preliminary findings have shown that C2Cl6 has a significant effect on both the tensile properties and fatigue crack propagation of the alloy tested, Grain refinement increased both the yield and ultimate tensile strength by more than 46%, and decreased the crack growth rate from 2,7 to 1,4 MPa Vm , However, the grain size seems to have a smaller effect on threshold stress intensity factor range. The fracture surfaces of specimens were examined optically and under the scanning electron microscope (SEM) to determine the relationship between grain size and fatigue properties.

Jan 1, 2005

By Mitchell P. Rothman

This paper concentrates on profits and other measures of return in the Canadian mining industry, especially in the non-mineral-fuels sector. The paper examines the historical patterns of mining profits, both before and after taxes, as compared with profits in other sectors of the Canadian economy, as well as some of the more important influences on mining profits. These include the prices of mineral products, provincial and federal tax policies with respect to mining , and the effect of inflation on mining profits and the financial position of mining firms - in each case, comparing mining with the other sectors of the economy. Finally, the paper provides an analysis of current and prospective rates of mining profits in relation to the capital required to ensure the future viability of the Canadian mining industry.

Jan 1, 1977

By John F. Dougherty

Recently, there has been much debate as to the relevance of reporting financial results using the conventional accounting systems, which is based on historical costs, during a period of rapid inflation. In the following paragraphs , the symptoms, if not the causes, of inflation, its detrimental effect on the financial soundness of business in general and the financial reporting changes being advocated to overcome perceived weaknesses in the present financial reporting system in accounting for the effects of inflation will be reviewed. Finally, a course of action as a sound approach to the financial reporting problem will be recommended.

Jan 1, 1978