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By R. P. D. Graham

It is almost exactly two hundred years since the foundations of the mining and metallurgical industries in Canada were laid. There '."'as nothing spectacular about this early start. It had to do with the most basic phases of these industries-the mining of coal and iron ore, and the manufacture of cast and wrought iron. At several points along the coast of Cape Breton island, coal seams may be seen outcropping quite conspicuously, and it is probable that they had been observed, and possibly worked in a small way, in very early times. However that may be, these coal seams have the distinction of being the first in North America of which there is any printed record, reference to them appearing in a volume by Nicolas Denys which was published in Paris in 1672. Regular coal mining in the district did not commence until about fifty years later, however. The metallurgists started their operations along the north shore of the St. Lawrence river. Here, at many points between Montreal and Quebec, are to be found deposits of bog iron ore, and in 1 730 a furnace for smelting such ore was established on the St. Maurice river. The St. Maurice forges continued in operation until 1880, and throughout that long period they were famed for the fine quality of castings produced, and also for a-superior wrought iron.

Jan 1, 1924

By M. Rafieazad, P. Fathi, X. Duan, M. Mohammadi, A. M. Nasiri

"Direct metal laser sintering (DMLS) is a metal additive manufacturing technology that creates highly complex components by fusing metal powder into a solid part. In this study, the impact of surface roughness on corrosion resistivity of AlSi10Mg_200C alloy manufactured through DMLS was investigated. The as-printed DMLS-AlSi10Mg _200C alloy was subjected to various surface finishing processes including grinding and sandblasting. The corrosion performance of the surfaces was then evaluated using potentiodynamic polarization testing and electrochemical impedance spectroscopy (EIS) in a 3.5 wt.% NaCl solution to mimic seawater environment. Surface characterization and corrosion morphology of the samples were assessed by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) spectroscopy. The results of this study show that the surface finishing process and the resultant surface roughness has a significant impact on the corrosion resistivity of the DMLS-AlSi10Mg_200C alloy in the seawater environment.INTRODUCTION Direct Metal Laser Sintering (DMLS), also known as Selective Laser Melting (SLM) (Sames, List, Pannala, Dehoff, & Babu, 2016), Laser Beam Melting (LBM), or Laser Metal Fusion (LMF) (Herzog, Seyda, Wycisk, & Emmelmann, 2016), is an additive manufacturing process that utilizes a precise, high-power laser to micro-join powdered metals and alloys layer by layer to form almost fully dense and functional components in three dimensions from the 3D computer-aided design (CAD) data. Complex geometries not possible with conventional manufacturing processes can be readily manufactured with high accuracy using the DMLS process with no need to time-consuming tooling."

Jan 1, 2018

By J. Nalaskowski

A study of the interfacial properties of the basal plane and the edge surfaces of talc is described in this paper. The isoelectric point measured at the two different crystallographic planes by the streaming potential method was found to be similar and exists at about pH 3.0. In the case of the edge surface the zeta potential increases at higher pH values which can be attributed to the hydration of magnesium ions at the edge surface. The atomic force microscopy (AFM) colloidal probe technique was used to measure interaction forces. For such experiments a 20 um talc particle was attached to the AFM cantilever and forces between the edge of the talc particle and two different crystallographic planes of talc were measured at various pH values. These measurements, while being qualitative due to the poorly characterized contact area, show differences between the properties of the base plane and edge of the talc and correspond to the results from streaming potential measurements. Finally, the differences in the hydration of the basal plane and the edge of talc are revealed from molecular dynamics (MD) simulations. The basal plane of the talc is much less hydrated than the edge, as can be seen from the water density distribution functions, which correlate quite well with the contact angle measurements at the basal plane surface and the edge surface of the talc sample.

Jan 1, 2006

By E. P. Wiechrnann, C. M. Castro, G. A. Vidal, F. A. Muñoz

Different authors and publications indicate that Optibar Segmented Intercell Bars cause a remarkable distortion in the distribution of the current in a cell group. However, these results were based in inaccurate computer based models and do not represent the technology. During the last trimester of 2010, a 92 cells circuit from Barrick Zaldívar EW plant was implemented with Optibar Segmented Intercell Bars. The technology was incorporated progressively without disrupting the plant production. Depending on operational conditions, this led to a 2 to 4% current efficiency increase and 3 to 5% specific energy consumption reduction. By October 2011, 40,000 tons of copper will be produced with the technology.

Jan 1, 2011

By Jerry Ran

Many large underground mines using the open stoping method have changed their primary applications of consolidated rock fill (CRF) to paste or consolidated hydraulic fill due to considerations of demand in infrastructure and equipment, system reliability, backfill capacity and material sources. However, some smaller or even large mines still use or consider using CRF for backfill purpose due to factors such as capital expenditure, availability or suitability of other fill types or in some cases local regulatory requirements. As demands on CRF applications diminish among major mining companies, there is a lack of recent literature on application of CRF to open stoping in design and operation. There are several methods being used for fill strength design. Results from these methods have been successfully applied to paste or hydraulic fill. However, the design strength for CRF is much higher than that determined by use of these widely accepted methods. In operation, CRF preparation and placement have significant impacts on the quality of placed CRF and therefore the mining performance. This paper reviews the current fill design methods and their applications to open stoping with presentation of the bench marking data, presents fill failure cases and various CRF preparation and placement arrangements and discusses quality assurance and control programs.

Jun 1, 2012

By R. Heikkilä

Today road construction sites utilize more and more information modeling in design phases as well as model based 3-D machine control systems in site operations. For main contractor, the management and control of all the site operations is a demanding task including also many challenges created by continuously developing new technology. In the paper, the main requirements for successful dynamic site management are introduced. The dynamic management means real-time possibilities for information acquiring, transfer and further utilization of the information in the management. An integration model to expand the current way of management and the utilization of present 3-D machine control systems is introduced. Different practical test results using two new different dynamic management systems are presented and evaluated. The first experiments and the results have been provided using the prototype system developed in a research project called DigiINFRA by the University of Oulu and Technical Research Center of Finland. Also, there have been tested a new commercial management system developed recently in Finland. In the conclusion, an expectation for the next generation for more dynamic road construction management methods is concluded.

Aug 1, 2013

By E. Ghali, W. Zhang, M. Robichaud, G. Houlachi

"The performances of six mesh and one plate dimensionally stable anodes have been investigated in the zinc electrolyte at 38oC and compared to conventional silver-lead alloy anodes. The electrochemical behaviour of these anodes was studied by cyclic voltammetry, galvanostatic, potentiodynamic, open circuit potential and electrochemical noise measurements. It was observed that at the end of 24 h of galvanostatic polarization at a current density of 50 mA/cm2 in the zinc electrolyte at 38oC, the mesh V had the lowest potential followed by mesh III, mesh VI, plate-V, mesh IV, mesh I, and mesh II electrode. When the potentials for mesh I, mesh III, mesh IV, VI and plate-V, mesh V were compared with that of the Pb-0.7%Ag anode (1920 mV/SHE), they were found to be 6%, 16%, 7% 10%, 17% lower, respectively.After 16 h decay following the 24 h polarization, the mesh III had the lowest corrosion rate (51 mS/cm2) among the seven specimens, followed by the plate-V, mesh V, VI, IV, I and II (221 mS/cm2). For the fresh surface as received, after two hour open circuit potential measurements, mesh I had the most positive (noble) potential (1382 mV/SHE) among the seven electrodes followed by the plate-V electrode, mesh V, mesh IV, mesh VI, mesh III and mesh II (751 mV/SHE). After consecutive series of electrochemical testing, mesh V, mesh III, mesh VI had lower corrosion rates (~ 343± 6 µA/cm2) than that of mesh IV, mesh I, plate-V, and mesh II (~ 644± 143 µA/cm2).INTRODUCTIONThe continued use of lead based anodes in the electrowinning process has been mainly due to their relatively low cost as compared to other materials (Msindo, Sibanda, & Potgieter, 2010). They have good electrical conductivity, stability during electrolysis, very good corrosion and wear resistance (Ivanov, Stefanov, Noncheva, Petrova, Dobrev, Mirkova, Vermeersch, & Damaerel, 2010). However, lead-based anodes give their high energy consumption and low corrosion resistance for electrowinning. To overcome these problems, Dimensionally Stable Anodes (DSAs) has been chosen (Msindo et al., 2010). Comparing to the traditional lead anodes, the DSA anodes have many advantages: (1) no contamination; (2) no loss of anode material, pure electrolyte; (3) lower gas bubble effect through special anode designs; (4) use of higher current densities (Msindo et al., 2010). The success of DSA anodes has been attributed to their chemical stability that allows them to maintain nearly constant dimensions during the life of the anode even when operating in environment with low pH values. Due to their stability, the consumption rates of DSA are as low as 1 mg/amp.y (Alfantazi & Moskalyk, 2003)."

Jan 1, 2016

By Tim Mann

"Like other operating mine sites, Placer Dome Inc. - Campbell Mine has taken important steps over the last few years to address environmental issues.This paper will provide specific insights into the implementation of an environmental management system at Campbell. In particular, it will focus on how Campbell developed its plan of action; the lessons that have been learned; the over-all steps that are being taken to enhance environmental stewardship and effectively manage relationships with key stakeholders.IntroductionThe development of an Environmental Management System at Campbell Mine has been part of a general development in management practices which has taken place at the mine during 1990. This paper will discuss the components of the management system in the topic areas of: direction setting; environmental organization; issue assessment; emergency response plan; training ; monitoring/verification; reporting and data management; and relationship management.Although this paper focuses on environmental management systems, the development of this system has partly been a function of responses to other issues which have been addressed concurrently with environmental concerns. These other issues include development of operations management, human resources practices, and safety management practices at the mine. As the Environmental Management System developed, various stakeholders associated with local environmental concerns were identified. This group of stakeholders include the local community; municipal, provincial and federal governments; government agencies; Campbell employees; and the Placer Dome Inc. Corporation."

Jan 1, 1991

By A. Monballiu, J. A. Martens, Y. W. Chiang, A. Van Audenaerde, R. M. Santos, T. Van Gerven, B. Meesschaert

In this work, bioleaching of non-sulphidic materials by applying chemoheterotrophic bacteria and fungi is studied. It was found that the tested fungus, Aspergillus niger, leached substantially more nickel from olivine than the tested bacterium, Bacillus mucilaginosus. A. niger also outperformed fungal species Humicola grisae and Penicillium chrysogenum in the leaching of olivine. Contrary to traditional acid leaching, the microorganisms leached nickel preferentially over magnesium and iron. On average, a selectivity factor of 2.2 was achieved for nickel compared to iron. This can potentially facilitate postprocessing of the leach liquor and reduce the cost. The impact of ultrasonic conditioning on bioleaching was also tested, and substantial increase in nickel extraction with A. niger was observed. This was credited to an increase in the fungal growth rate, the promotion of particle degradation, and the detachment of the stagnant biofilm around the particles. Furthermore, ultrasonic conditioning enhanced the selectivity of A. niger for nickel, resulting in a selectivity ratio for Ni/Fe equal to 3.5. The chemical resistance of the selected microorganisms to several heavy metal and metalloid (As(III,V), Cd, Cr(III,V), Ni, Pb, Zn) was evaluated. It was found that, with the exception of As(v) and Cd, A. niger has high tolerance to these components. Therefore, this biohydrometallurgical route can potentially be applied to non-sulphidic wastederived materials, such as industrial slags, ashes and sludges.

Jan 1, 2014

By H. Tan

The effect of carbonaceous matter on gold extraction was investigated in cyanide systems with pure gold as well as pre-robbing sulfide gold ores. Auger studies demonstrated that the carbonaceous matter preferentially smeared on iron sulfide rather than aluminosilicate surfaces during wet or dry grinding. During mechanically mixed leaching, coating of sulfides and silicates and stripping of carbonaceous matter occurred simultaneously. TEM and XPS studies indicated preferential coating in the form of elemental (graphitic) carbon at the edges and the defect sites of particles. Interestingly, carbonaceous matter extracted from the gold ore was predominantly graphite and not preg-robbing in a solution with a high KCN concentration. However, the carbonaceous coating had a significantly detrimental effect on gold dissolution when gold was pre-ground with the gold ore. Artificial coating on gold surfaces with the natural carbonaceous matter from the ore was also found to substantially retard gold dissolution. With the addition of the natural carbonaceous matter from the gold ore, gold extraction from two non preg-robbing sulfide gold ores was inhibited owing to carbonaceous coating. The presence of carbonaceous matter significantly reduced the current density for gold oxidation and increased the current density for pyrite oxidation. This could explain the fact that carbonaceous coating hindered gold dissolution while enhanced sulfide preg-robbing.

Jan 1, 2005

By L. Veleva, Garcia. A., G. Perez

Aluminum is a metal used for the transmission of electricity of high voltage, in the construction industry and other areas. In atmospheric conditions aluminum forms an oxide layer (Alz03'H20) as a result of its corrosion, entering the passive state. The oxide layer can be destroyed by the presence of ions (Cr, SOx-n) developing localized (non uniform) corrosion attack by pitting, difficult for evaluation. The concepts of fractals and self-similarity were used in this study for the characterization of the development of localized corrosion. Images obtained with a scanning electron microscope (SEM) of samples of electrolytic aluminum wire that have been exposed during one year in ruralurban and marine-coastal environments of the humid tropical climate of Mexico, have been processed. The development of pitting has been studied as a function of time, making a statistics of the frequency of appearance of pits versus the area occupied by them. The data show that the distribution of the pits follows a power law. Therefore, the concept of self-similarity can be applied for the study of the phenomenon of localized corrosion, describing their development with time.

Jan 1, 2006

By Y. Hayashi, A. Fuwa

To analyze zinc vaporization kinetics of zinc smelting slag in the ISP furnace, reduction reaction rate of zinc oxide from ZnO-FeOx-CaO-SiO2 slag system with CO-CO2-Ar gas mixtures has been measured by a therm o-gravim etric apparatus at various ZnO content, Pco, and temperature. The reduction rate was measured under a chemical reaction control in the initial three minutes where surface zinc content can be assumed constant. Through the reaction rate dependency analysis on ZnO contents, Pco and temperature, discussion has been made on its reaction mechanistic information in terms of rate coefficient, adsorption/desorption mechanism and activation energy.

Jan 1, 2008

By Roger J. Berdusco

Kaiser Resources Ltd. owns and operates a 5-million-tonper- year open-pit and hydraulic coal mine near Sparwood in southeastern British Columbia. Since 1969, Kaiser has maintained a field-scale reclamation program dedicated to the reclamation of disturbances associated with past and present mining and exploration activities . Since that time, over 1400 acres have been treated using modified forestry and agricultural techniques with encouraging results.

Jan 1, 1978

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 F. Prescott, D. Hiam-Galvez, J. Hiam

Mines are frequently located in remote areas with little conventional employment and few opportunities for the existing population. The development and operation of the mines results in several years of intense activity followed by a near-complete reduction in employment and opportunities after the mines are closed. Designing Sustainable Prosperity (DSP) is a method for rectifying this situation by designing for long-term growth in areas that host mines. This process involves the participation of local and national governments, local community, mining companies, investors, academics and those with sector expertise. The mines will be the catalyst for regional sustainable development. If successful, long-term economic and environmental prosperity should be the result for the areas affected by mining and, in some instances, promoting the regions as centres of excellence for a particular industry. This paper will describe how the concept works using the copper producing region of Peru and Chile as an example. Designing sustainable prosperity starts by looking at regions based on the natural resources and skills available, the infrastructure and possible energy sources. Integrated natural resource models and innovative market studies, followed by education and skills requirements, are then established to determine the potential for the region and what needs to be done to realise the possibilities. INTRODUCTION Industry 4.0, or i4.0, dubs the fourth and current industrial revolution. Where previously they have been founded on ever-increasing consumption and production, i4.0 distinguishes itself by its partial focus on reducing resource intensity; lightweighting, energy efficiency, sensors and automation to improve resource efficiency. Industry 4.0 is an era of artificial intelligence, genome editing, biometrics, renewable energy, 3D printing, autonomous vehicles and the Internet of Things (Lu, 2017). These drivers represent key opportunities for the economic future of nations and regions.

Jan 1, 2019

By Newell G. Alford

COAL companies are definitely becoming conscious of the need for better organization. Mechanized mining and the intricate preparation of coal have brought with them the demand for better trained and more highly skilled mining personnel. Refinement in coal mine management is increasing the demand for young graduate engineers to start in the lower grades of the reorganization and prepare themselves to meet rapidly increasing coal mining responsibilities. The interest is wide in scope and extends from self-helps, extension work, and management study at the mines to stimulation of interest in coal mining amongst undergraduate mining students, leading to their permanent employment after graduation. Data by the United States Bureau of Mines show the total annual value of coal production (bituminous and anthracite in the U.S.) through the past 22 years as being more than 38 per cent of the combined value of all ocher mineral industry products. Natural-gas production has gained rapidly on coal since 1916; petroleum exceeded coal beginning with 1934 (see Figure 1). For this 22-year period, the Committee on Student Interest in Coal Mining, in the A.I.M.E., made a survey of the mining schools in Canada and the United States to show the approximate absorption of young graduate mining engineers by the coal industry. In 1938, 232 mining engineers were graduated as compared with 42 in 1918 (a war year) and 180 in 1923. From 1923 to 1929 the graduates declined to another low of 90, but from there on there was a rapid annual increase in the graduating output, reaching a total of 232 in 1938 and continuing upward to a maximum of over 325 graduating this present month.

Jan 1, 1940

By W. van der Merwe

With the gold industry looking to process more complex ores, the online measurement and control of cyanide addition to the gold leaching circuit has become more crucial. This paper compares the two commonly employed "free" cyanide online analysis methods (amperometric and potentiometric end-point silver nitrate titration) with the common site laboratory rhodanine endpoint silver nitrate titration and ion selective electrode methods. Measurement differences between these methods are presented and discussed for cyanide solutions containing copper and zinc with varying cyanide to metal ion ratios. The resulting cyanide available to leach gold is also compared with these measurements.

Jan 1, 2011

By LUKE O. LINDOE

A major clay products industry in the Medicine Hat area since before 1910 has maintained a continued interest in the clays of the Cypress Hills. For the first forty years the materials used were local red-burning Cretaceous and Pleistocene clays and sands and high-quality stoneware clays of the Whitemud Formation at Eastend, Saskatchewan. Recently a much broader spectrum of raw materials has been brought into use. Including the exposures of the Eagle Butte structure, the Cypress Hills present a 1200 m section of clay-like sediments. Of this 1200 m about 94 per cent, the high montmorillonite shales of the Upper Cretaceous, can be considered useless, or nearly so; the remaining six per cent, all fresh-water beds, presents a wide variety of potentially useful materials. The development of these clay resources is complicated by deep surface creep on the south flank of the Cypress Hills, by largescale slumping on the north flank and by a structural complex in the Eagle Butte area.

Jan 1, 1984

By F. Dubuc

"The Adams Mine of Jones & Laughlin Steel Corporation is situated on the Boston Township iron range near Kirkland Lake, Ontario. Eight different orebodies have been outlined, with a total open-pit crude tonnage of. about 100,000,000 tons or the equivalent of 30,000,000 tons of concentrate. The ore consists of fine-grained, well-bedded Early Precambrian iron-formation composed essentially of alternating layers of chert and magnetite. Grade averages about 22 per cent magnetic Fe.The iron range varies in width from 3,000 to 4,000 feet and is made up of several horizons of iron-formation, cherty ""quartzite"" and volcanic rocks. The latter consist mostly of basic lava flows and minor amounts of tuff. Dips are rarely Jess than 50 degrees, and the range is believed to represent an overturned limb of a major synclinal structure. Dykes of syenite and lam prophyre, along with local younger diabase, intrude the rocks of the iron range."

Jan 1, 1966

By W. T. Sampson

Introduction The Kirkland Lake (Ontario) property of Wright-Hargreaves Mines, Limited, - consists of four claims. The two main shear zones or 'breaks' of the Kirkland Lake camp extend through three of these claims, for a distance of approximately 3,500 feet. These claims are on the northeast side of the original lake. The water in this section of the lake has now been replaced with mill tailings. The degree of success of any completed undertaking, especially in the mining industry, reflects the personnel involved. I state with pleasure that the successful deepening of No. 5 winze from 6,400 feet to 7,272 feet was largely due to the co-operation and skilled workmanship of Shaft Captain J. Myelde and his efficient 'leaders'. This winze was sunk at a time when it was most difficult to obtain experienced shaftmen, with the result that the crews did not wholly consist of experienced men (although their desire to learn shaft sinking soon gave good results). This condition added greatly to the responsibilities and duties of those in charge, whose first consideration was for the safety of those engaged in the work, and I take great pride in recording that the entire sinking programme was completed without a lost-time accident. Location of Winze Due to the information obtained through deep diamond-drill holes collared below the 6,000-foot level being of sufficient importance to warrant further exploration, it was decided to deepen the existing No. 5 winze rather than sink another winze. This decision meant that the sinking must be co-ordinated with and proceed simultaneously with operations in the winze, where mining was being carried on between the 3,900-foot and 5,100-foot horizons, inclusive.

Jan 1, 1948