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By Steven D. Botts

The Antamina project, owned by BHP Billiton Plc, Mitsubishi Corporation, Noranda Inc., and Teck Cominco Ltd. , is a $2.3 billion copper/zinc project, located in the Ancash Department in Perú. The project consists of an open pit mine, a 70,000 ton per day concentrator, a 302 Km. long concentrate pipeline, port facilities, a new access road, power line, and town site. The project is designed to produce up to 1.5 million tonnes per year of copper and zinc concentrates over a 23-year project life, and will be the third largest producer of zinc and the seventh largest producer of copper in the world. This mega project is the largest mining investment in the country and, during its construction stage, was the most important construction project worldwide. On May 28th, 2001, Antamina commenced testing operations and four months later, it reached commercial production. Antamina was officially inaugurated on November 14th, 2001 by Peruvian president Alejandro Toledo. The construction stage of the project generated 8,000 direct jobs, with a peak of 10,000 employees, and 30,000 indirect jobs. The permanent workforce consists of approximately 1650 employees, the vast majority of which are Peruvian Nationals; around 30% of whom came from the department of Ancash where the deposit is located. Approximately 5,800 indirect jobs will be generated from the project. Independent sources state that Antamina will increase the Peruvian mining exports by 30% and Peruvian GDP by 1.4% within its first year of full operation in 2002. Since winning the privatization bid for the project in 1996, the company has implemented a successful approach to community development and environmental protection based on sustainable development principals. Throughout the development of the project, a number of initiatives have been undertaken to ensure full involvement of the local populations in community development activities and the company?s environmental program. Due to its size, difficult logistics, cultural considerations and financial aspects, the project has faced a number of unique challenges in the area of environmental protection and management of community interaction. Antamina has been innovative in its approach to these issues, and as a result, has set new standards in Perú for environmental and community management, and sustainable development.

May 1, 2002

By W. T. Robson

Introduction Ground failure, violent or otherwise, is a problem to be contended with wherever underground operations are carried out. The character and extent of the failure, whether superficial or of more serious proportions, is determined by a number of factors, among which might be mentioned: the depth and dimensions of the underground workings; the types and distribution of wall rocks; structural features of the ore and enclosing rocks; the degree of metamorphism; the dip of the orebody; concentration of mining operations; the rate of mining; the history of the excavations made on the orebody in question. This last factor implies the consideration of such points as the arrangement and distribution of stoping both past and present, the current sequence of scoping, the type and effectiveness of the support used in old and current workings, and the amount and distribution of unmined parts of the lode. With such a variety of conditions, it is only natural that the situation at one place in a mine will not be the same as that obtaining in another part of the same mine and, more than likely, will be quite different in another property.

Jan 1, 1946

By C. J. Coulson, G. A. McKay, A. M. Cormie

"The Leitch mine, in the Beardmore area, Thunder Bay district, Ontario, is a part of the Leitch estate. It includes a group of patented claims, staked by P. A. Leitch of Port Arthur early in the century, along bands of jasper, hematite, iron-bearing slates, carbonatized schists, and greywacke, commonly known as 'iron formation'. The folding and shearing in these variably interstratified beds is a striking structural feature. The vein pattern is very definitely related to these structures.ROCKSThe rocks in the area are typical Keewatin lavas-greenstone-overlain by a series of Timiskaming sediments consisting of arkosic greywacke, iron formation, slate, greywacke, conglomerate, and greywacke, in this order from the contact. The sedimentary beds are generally conformable with the older rock contact except on local folds.Small intrusions of diorite occur as nearly vertical dykes and are believed to be of Algoman age. To the northwest of the mine there are larger intrusions of granodiorite belonging to the same period.Several dykes of quartz diabase up to 100 feet in width, striking generally north and south, with a vertical dip, cross the property. These have been classified by W. C. Laird as pre-Keweenawan in age. One of these dykes in particular is of importance for it cuts through the No. 2 vein and serves as a pillar when stoping. It is approximately 6 feet wide.The youngest rock type represented is a sheet of olivine diabase that extends over an area of thousands of square miles in and around lake Nipigon. It underlies most of this area and its outcrops form some of the most interesting topographical features, with fault scarps rising hundreds of feet. In the vicinity of the mine shaft the sheet is about 600 feet thick and extends from a depth of 1,871 feet to approximately 2,470 feet. It has a dense, hard, chilled margin and a sharp, tight contact. It intruded the sediments with very little lateral disturbance. The chief effect was baking, which darkened and hardened the greywacke near the contact. The sheet dips flatly to the cast."

Jan 1, 1954

By Unknown

With the present-day trend of rising labour costs and a lowering of production efficiency of workmen, it has become imperative that every effort be made to use manpower to the greatest advantage and to mechanize mining as much as possible. During the past few years this trend has gained much prominence in the Porcupine camp. In view of this, the executive of the Porcupine Branch considered that the Mechanical Movement of Muck would be a very timely subject for a Symposium. Accordingly a Committee was formed, with A. K. Douglass, Mine Superintendent for Delnite Mines, Ltd., as Chairman, and the Symposium was held in the Auditorium of the McIntyre Community Building, Schumacher, on March 25th last. Papers dealing with shovel loader and mechanical scraper operation at six of the larger mines of the camp were presented and discussed, and a tabulation was prepared giving data on the machines in operation at a total of eleven mines. The papers and tabulation, reproduced below, will doubtless be of considerable interest to operators of mines in all parts of Canada.

Jan 1, 1948

By C. Gerow

THIS paper is entitled "Some" problems, rather than "The" problems, met in selling coal, since the problems to be met in selling any commodity have to deal with an infinite number of circumstances and conditions. These are believed to be more varied in the case of coal than probably any other commodity. This is due, perhaps, to the fact that coal has been one of the basic materials in the guiding of industrial and national achievement for the past two hundred years. During this time its use has developed from a most haphazard one to uses involving all modern scientific methods, which, rather than simplifying matters as regards the marketing of coal, have added many fresh problems, and these vary according to the particular market served. Since the concern of this paper is primarily the selling of Nova Scotia coal, it is proposed to deal chiefly with some of the specific conditions met in the markets presently served by this coal. For the purpose of discussion, these markets may be considered as divided into three main groups, namely, the Maritime market, the Quebec market, and the Ontario market. THE MARITIME MARKET First of all, let us consider the Maritime market. This is a market which has been regularly served by Nova Scotia coal since coal mining became the first industry in Cape Breton, slightly over one hundred years ago. Conditions as applying to the use of coal have naturally tended to adjust themselves to the characteristics of the coal most readily available, and, therefore, marketing problems are fewer in the Maritimes than in districts where many coals of varied characteristics are offered. Up to recent years, the problems involved were chiefly those of providing satisfactory service insofar as de-liveries were concerned. However, with the speeding-up of manufacturing processes and the necessity of reducing costs to a minimum, users of coal have become interested in obtaining coal that will give the most economical service. It is, therefore, now of importance that the salesman should have full knowledge of the particular conditions applicable to each customer's use in order to deal to the best advantage.

Jan 1, 1936

By Earl T. Hayes

This paper briefly reviews the laws enacted in the United States governing the coal miner. It discusses amendments to the Coal Mine Safety Act and describes the provisions of the Metal and Non-Metallic Mine Safety Act.

Jan 1, 1969

By J. N. Van der Merwe, M. Mathey

"We present an analysis of the mechanical properties of coal specimens from various coalfields and seams in South Africa. Our database comprises of 1800 test results from uniaxial and triaxial compression tests, as well as indirect tensile strength tests, which we collected from the various mining houses and research agencies in the country. We inspected the database for possible errors and present a brief description of the verification procedure in the paper.In the analysis, we reveal that the collected samples of strength and elastic properties of South African coals can be represented by single lognormal or normal distributions with only few outliers. This finding indicates that the samples realistically approximate the population of mechanical coal properties in the country and may suggest that the properties are randomly distributed. Significant coalfield- or seamspecific trends for the mechanical properties of coal are not clearly discernible from our data.Typical coefficients of variation for the individual mechanical properties range between 25-50 % on a country-wide and seam-specific level of analysis. Average uniaxial compressive strength values, however, are closely clustered for all seams. A comparison with data available from international coal strength studies show the distinct difference between South African coals and seams in countries of the Northern Hemisphere, where differences in the average coal seam strength are more pronounced.We observe that the number of specimens whose failure mode is influenced by the presence of natural discontinuities reduces drastically with the application of very small confining pressures to the specimens. Further, the strength-reducing influence of discontinuities diminishes with increasing confining pressures."

Jan 1, 2015

By Martin Grenon

This paper presents two case studies where fracture set orientation was quantified using three methods: a simple fracture pole grouping, a Fisher distribution and a Kent distribution. The three fracture orientation representations were then used as inputs for kinematic slope stability analysis. Differences showed up in the probability of sliding for all instability modes considered.

Aug 1, 2013

By R. V. Kumar, C. Schwandt, S. Subramanian, S. Sampath, S. Vimalnath

Waste waters and industrial effluents containing toxic heavy metals such as Pb, Hg, As and Cr, beyond permissible limits (0.1 ppm, 0.01 ppm, 0.02 ppm and 0.05 ppm, respectively) (WHO, 2011), pose serious threats to the ecosystem, when discharged into the environment. It thus becomes imperative to monitor the concentration of the toxic heavy metals and treat them before discharging. In this study with the above objective in mind, a microbial sensor has been developed using P. aeruginosa cells drop coated onto a carbon paste electrode (CPE) for the detection of Pb(II) ions in aqueous solutions. Detailed biosorption experiments confirmed that complete bioremoval of lead could be achieved using P. aeruginosa cells under optimum conditions of pH and biomass loading. For the electro-analytical determination, the Pb(II) ions were initially preconcentrated on the P. aeruginosa modified CPE, reduced and then anodically detected with oxidation of Pb0 using differential pulse anodic stripping voltammetry (DPASV) technique. All the experiments were carried out in the presence of 0.1 M sodium acetate buffer and KNO3 as background electrolyte. The parameters namely pH, scan rate, biomass loading, deposition potential, deposition time and concentration of Pb(II) ions were optimized for the biomass modified CPE, to obtain maximum voltammetric response. Under the optimized conditions of pH 5.6, scan rate of 0.008 V/s, biomass content of 1.7–1.8×109 cells/mL, deposition potential of –1.2 V, and deposition time of 500 s, the developed microbial sensor showed a linear response for the peak current between 0.5×10-5 M and 1×10-8 M of Pb(II) ions with the R2 value of 0.9979. The lowest limit of detection (LLOD) was determined as 2.4×10-7M of Pb(II) ions (0.05 ppm). The redox mechanisms of Pb(II) ions on the P. aeruginosa modified CPE surface are discussed.

Jan 1, 2016

By K. Sugawaral, W. Tongampl, K. Hiruta, Takasaki Y., A. Hosoi, T. Katol, A. Shibayamal

Printed circuit boards of discarded personal computers, televisions, mobile phones and so on contain a significant amount of valuable metals. For the recycle of valuable metals contained in the printed circuit board wastes (P CB W), the effect of temperature on chlorination-volatilization of metals under chlorine gas flow was studied. The experimental sample used was powder of two types: crushed PCBW (Sample 1) made from PC and industrial machines, and crushed-combusted PCBW (Sample 2) made from Sample 1. The principal element in Sample 1 and Sample 2 was copper, about 13 wt% and 20 wt% respectively. Sample 1 was composed of pure metals such as copper, tin and lead. In comparison, Sample 2 consisted of oxide metals such as copper oxide, tin dioxide and silicon dioxide. The two samples were heated at predefined temperatures (ranging from 300 °C to 900 °C) in chlorine gas. The chlorine gas flow into the furnace was set at a rate of 100 mL/min. As a result, copper in Sample 1 began to volatilize at 600 °C and completely vaporized at 700 °C. While in Sample 2, copper started to volatilize at 600 °C and reached 100% vaporization at 800 °C. For Sample 1, zinc finished volatilizing at 500 °C, while for Sample 2, zinc volatilization reached only about 80% (maximum). Also, lead, nickel and titanium showed similar results. Consequently the volatilization rate of Sample 1 is higher than Sample 2 and the temperature dependency was verified for copper, lead, zinc, nickel, antimony, titanium and chromium. In fact, the volatilization rate of these metals increased with the temperature. This result reflects the difference between pure metal and metal oxide, as Sample 2 was combusted before the chlorination-volatilization test. Moreover, the chlorination reaction may be accelerated by a reductive atmosphere because Sample 1 contains carbon. In this study, the volatilization behavior of some valuable metals in PCBW by chlorine gas was observed. Further improvement in the rate of volatilization can be achieved by optimizing the experimental conditions.

Jan 1, 2011

By D. J. MacKinnon, Kazi E. Haque

Ammonia present in a variety of mine/mill waste waters was almost completely oxidized to nitrogen by chloride mediated electro-oxidation. A closed circuit operation of preconcentration of ammonia on a suitable adsorbent (e.g. zeolite or a resin) followed by brine stripping of ammonia and electrolysis of the strip liquor seems to have sound technical, economic and environmental merits. The removal of ammonia, cyanide, cyanate or thiocyanate from a mine/mill waste water (e.g. gold mill), either individually or collectively, is also feasible by chloride mediated electro-oxidation technique. Further R&D investigations are necessary for the development of a closed circuit operation for the removal of ammonia, cyanide and thiocyanate; and also to obtain technical data for process cost estimates

Jan 1, 1996

By Mike Johnson, Greg Andrews, Niels Verbaan, David Dreisinger

"The Search Minerals Foxtrot project in Labrador represents a significant Canadian resource of rare earth elements rich in the sought after heavy rare earth elements (19.8% HREE/TREE). A preliminary economic assessment of the project indicated that the project is technically feasible and economically attractive. A variety of metallurgical test programs have been undertaken which have led to significant streamlining and simplification of the process flowsheet. The improved flowsheet should allow Search to reach production earlier and will use conventional processing equipment. The results of these test programs are presented and discussed in this paper INTRODUCTIONSearch Minerals Inc. (Search) is exploring and developing a number of deposits for rare earth element (REE) recovery in Labrador, Canada. The Port Hope Simpson District is in the southeast of Labrador and is highly prospective for heavy and light rare earth elements. The Foxtrot deposit sits within the Port Hope Simpson REE District (Figure 1), which is 70 km long by up to 10 km wide. The infrastructure available at Foxtrot is excellent; a deep-water port, air strip, and road and power infrastructure are pre-existing at St. Lewis. The three communities of Port Hope Simpson, St. Lewis and Mary’s Harbour are in close proximity to the site."

Jan 1, 2016

By R. D. Brown

"An adequate level of R & 0 is crucial to achieve gains in productivity and to strengthen Canada' s position in an increasingly competitive world ." So stated Finance Minister Jean Chretien in his April 10, 1978 budget speech, on announcing a new measure designed to increase the productivity of Canadian industry and to assist in the creation of new technology. The effect of the new measure, which permits an income tax deduction of 150% of certain research and development (R & D ) expenditures , can reduce the after-tax cost of a marginal dollar 's worth of such expenditures to as little as 20 cents . This article discusses the income tax treatment of R& D expenditures in general, and describes in particular the income tax incentives which relate to R& D.

Jan 1, 1978

By Rob Boom, Yasuyuki Tozaki, Frank M. Wheeler

Selection of a suitable site for a metallurgical plant is crucial for the success of the business case. For a brownfield project, with the decision to locate the project on a site with existing production facilities and activities, the selection of the site has been made. For a greenfield project, important economic and logistical considerations include proximity to primary and secondary resources and/or to the market, infrastructure, and access to energy and water. National and regional aspects, including the social license to operate, can be decisive in final site selection. Key to recruiting and retaining a labour force are proximity to urban areas, along with weather and health conditions at the site. Risk factors include site geotechnical parameters and topography, contamination, as well as probability and types of potential natural disasters.

Jan 1, 2015

By Allan J. Guse

The primary limiting factor for hoisting capacity from great depths is the self-weight of the typical steel wire ropes used for mine hoisting. Steel wire ropes possess properties making them very suitable for mine hoisting including high strength and durability, but have the negative characteristic of being relatively heavy in comparison with their strength. Also, as hoisting depths increase, the service life of steel wire ropes decreases due to the higher stresses and physical effects on the ropes. The significantly higher strength-to-weight ratio of synthetic ropes compared with steel ropes offers the primary advantage of hoisting a larger payload with a similar size rope and hoisting plant. The beneficial properties of synthetic ropes could be used to improve the overall economics of deep underground mining both for new deep shaft projects and for existing mining operations expanding to deeper orebodies. A research and development program has been initiated to evaluate the suitability of a fully synthetic rope for the mine hoisting application, including rope discard methodology and NDT testing. The three phases/projects are: 1) proof of concept with focus on coilability under load (successfully completed in 2012); 2) high speed and load durability optimization & NDT Development; and 3) in-situ mine trial.

May 1, 2013

By D. Nie, M. Ren, T. Mo

This paper studied the phenomenon of room temperature creep deformation at crack tip and its effect on fatigue crack growth rate of a X-70 pipeline steel using compact-tension (CT) specimen on a MTS 810 testing machine. Time-dependent deformation at the crack tip under constant load was observed in this steel at room temperature and the amount of deformation produced was seen to depend on loading rate and the magnitude of stress intensity factor. It is found that there exists a critical stress intensity factor below which the deformation decreases with time when the applied load remains constant. It is also found that the occurrence of room temperature creep obviously affects the subsequent fatigue crack growth rate. The observed behavior was explained based on dislocation theory.

Jan 1, 2005

By Matej Petružálek, Tomáš Svitek, Tomáš Lokajícek

"Migmatite from the Skalka region (Czech Republic) was chosen as the experimental rock material. It has macroscopically visible plane parallel structure (foliation). The foliation was caused mainly by biotite grains arrangement. The cylindrical samples of migmatite with subhorizontal, subvertical and oblique foliation were uniaxially loaded up to the failure. Network of 8 broad band sensors was employed for acoustic emission monitoring and ultrasonic sounding. A grid search method with anisotropic velocity model was used for AE hypocenters localization. The source types of successfully localized events were determined from the average first arrival amplitude. Structural anisotropy of tested rock material caused the anisotropy of its mechanical properties (peak strength, Young’s modulus) as well as a different way of fracturing process in dependence on the angle between axial stress and foliation plane. The combination of splitting, shearing and sliding was found to control the fracturing of sample with subhorizontal foliation. The shearing and sliding was dominant in fracturing of samples with oblique foliation. With greater dip of foliation, the role of sliding increased at the expense of shearing. Due to the favorably oriented system of microcracks already present, the shearing and splitting was at the same level during fracturing of the sample with subvertical foliation before nucleation began.INTRODUCTIONThe process of failure of low porosity rocks depends on their mechanical properties and actual stress and temperature condition. At the low pressure and low temperature, the most common way is brittle failure, which is a progressive process requiring the initiation, growth and coalescence of cracks (Lockner, 1993). Stress strain behavior of low porosity crystalline rocks, during the laboratory compression experiments, is divided into four characteristic stages: crack closure, elastic region, stable crack growth and unstable crack growth which leads to the brittle failure, Brace et al. (1966) , Bieniawski (1967), Lajtai (1974), Cai et al. (2004), Nicksiar and Martin, 2012 and 2013.The fracturing process of stressed rock begins with the crack initiation (sci), which for low porosity rocks occurs approximately at 40-50% of peak strength (sp) (Cai et al., 2004; Nicksiar and Martin, 2013). After the sci, the dilatancy begins and stable crack growth follows up to the crack damage threshold (scd), which is approximately at 80% of sp (Cai et al., 2004). After crossing the crack damage level, there is an unstable crack growth accompanied with nucleation of fault plane (sn) at 97-100% of sp. (Rao et al., 2011). The stress drop accompanied with formation of macro scale shear failure plane follows after peak stress is crossed."

Jan 1, 2015

The negative effects of pyrite and pyrrhotite on thiosulfate gold leaching have been investigated. Possible remedies to reduce some problems are discussed. In a gold bearing pure silicate ore, 92% of gold could be extracted within 3 hours using a solution containing 0.2 mol/L ammonium thiosulfate, 0.9 mol/L ammonia, 30 - 300 ppm copper sulfate and 8.6 ppm dissolved oxygen at pH 10.26. The thiosulfate consumption was 7.1 kg/t under these conditions and could be further reduced to 3.5 kg/t by decreasing the dissolved oxygen to 0.3 ppm. Addition of 16% pyrrhotite or pyrite into the silicate slurry led to a decrease in gold extraction by 2% or 9% respectively and an increase of thiosulfate consumption by 11 kg/t or12.8 kg/t respectively in three hours. Several adjustments, such as increasing copper ion and ammonia concentration and reducing the dissolved oxygen level to 0.3 ppm resulted in increased gold extraction and lower thiosulfate consumption despite the presence of these sulfides.

Jan 1, 2005

By A. V. Tarasov

There are still a number of copper smelters in the world using the roasting and smelting process flow diagram for treating sulphide raw materials. The technical, economic and environmental performance indicators of such operations are inferior to the respective indicators of advanced processes. First of all with respect to copper and sulphur recovery: 95% and 75% as compared with 98% and over 90%, respectively. Based on the studies of the single-stage smelting process to produce white metal and blister copper conducted during recent years an analysis of the feasibility of roastingsmelting technology improvement was carried out in the Gintsvetmet Institute to substantially increase the copper and sulphur recoveries. On the basis of this analysis, it was proposed to modernize the technology and equipment within the framework of the existing process flow-sheet. The proposed modernization implies an increase in the roasting temperature; higher desulphurization degree in the process of roasting; a number of modifications in the roaster design depending on the particular conditions of a given operation; addition of lime flux to the feed charge to roasting; and transition to combined calcium-silicate smelting slags. The metallurgical and energy computations made have indicated that the proposed modifications of the technology will improve the copper and sulphur recovery up to 98% and 90%, respectively. The required capital investments have been estimated using as an example a particular copper smelter, the payback period determined taking into consideration additional output, fuel saving and a reduction in fines for sulphur emissions. For comparison, the capital cost of a smelter modernization is given for change-over to basically new autogenous Ausmelt, Outokumpu and V anyukov smelting technologies.

Jan 1, 2007

By B. Holaday, H. McLaughlin

Orano Canada Inc. (Orano) operates the McClean Lake mill, located in the Athabasca Basin region of northern Saskatchewan. It processes high concentration uranium ore, delivered in slurry form from the Cameco Corporation operated Cigar Lake mine. After the ore slurry is leached at the McClean Lake mill, the leach residue solids are washed in a process known as counter-current decantation (CCD). This process uses six thickeners to facilitate counter-current washing of solids with diluted acid, flocculation and settling, as well as pumping the washed leach residue to the tailings neutralization circuit (TN), and the uranium laden aqueous to the solvent extraction circuit (SX). Challenges in settling the slurry in CCD started in early 2017. This is largely due to the variation in fines content of the slurry (D80≤75μm), and clay content. There are several changes that have allowed the mill to adapt to the evolving challenges of settling leached Cigar Lake leach residue. Flocculant selection and mixing, temperature effects, bed level management philosophy, and centre-well feed density are key parameters that have been explored as part of adapting to changes in Cigar Lake ore quality.

Jan 1, 2020