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By Dale L. Pitt

Introduction In opening up a new country, one of the most vital problems is that of transportation Without roads, railways, or water routes, development is very slow because these are the arteries through which the life-blood of the country flows. British Columbia is unusually fortunate in having along its western coast, for some 600 miles, a stretch of inside water unequalled, for comfortable and safe navigation, by any other similar stretch of ocean in the world. This solves in a general way the major north and south transportation problem for the coast section, and offers comparatively cheap rates for the shipping of all commodities. The principal cities and centres of distribution will naturally grow up on the coast. These cities, however, must have methods of communication with the hinterland, and it is the necessity of supplying these, as feeders to the principal ports, which presents problems of considerable magnitude.

Jan 1, 1930

By P. G. West-Sells

At Barrick's Zaldivar Copper Mine in Chile, the addition of sulfuric acid to the ore going to heap leaching is a major expense. A process in which a portion of this acid is replaced by elemental sulfur added to the heap has been developed by Barrick and Westcoast Biotech that has the potential for significant cost savings. Initial shake flask tests with plant raffinate solution indicated that oxidation of elemental sulfur by a culture of sulfur-oxidizing bacteria, some indigenous to the Zaldivar heap, showed a significant lag period. This lag period could be reduced by dilution of the raffinate, but dilution would not be economical to implement at Zaldivar. Short (0.75 m) column tests indicated that after the initial lag period, sulfur biooxidation occurred steadily and the acid requirement for obtaining the same copper recovery as the control without sulfur was reduced by as much as 13 kg/t. These tests were followed by taller (5.1 m) column tests that confirmed the reduction in acid consumption, with no negative effect on copper extraction.

Jan 1, 2007

By A. Sokolov, E. Hasikova, V. Gostilo, V. Titov

Introducing online X-ray fluorescence (XRF) analyzers in the mining and processing industries can lower costs and improve the representativeness and speed of analysis. The applicability of the CON-XTM industrial conveyor XRF analyzer for continuous measurement of potassium content in process materials was demonstrated at various stages of potassium muriate (MOP) production. The CON-X analyzer produced reliable and accurate results for sylvinite ore (27–36% KCl), MOP cake after flotation (88–97% KCl), and NaCl residue (1.5–5% KCl). Tests of the analyzer at an MOP-producing plant showed a < 0.5% difference between online and laboratory results.

Jan 1, 2014

By E. Engelbrecht

"A pressure non-oxidative leach is employed at Anglo American Platinum Base Metal Refiners to extract nickel from a slow cooled matte. The design base requires two 80 m3 autoclaves in parallel to achieve a nickel extraction of 60% at the nameplate capacity of 32.4 ktpa nickel plated. Isothermal modelling of mineralogical and chemical concentration profiles, through a reactive mass balance, permitted rate constant parameter estimation and selection of the most probable reaction pathway. The model was validated with plant data up to a capacity of 26 ktpa Ni plated and suggested by extrapolation that nameplate capacity may be viable through one 80 m3 autoclave.INTRODUCTION Anglo American Platinum Base Metal Refiners is situated on the outskirts of Rustenburg in the North-West province of South-Africa. The refinery produces nickel cathode, copper cathode, cobalt sulphate powder, covellite rich copper pressure leach residue and bulk sodium sulphate through an integrated circuit that refines slow cooled converter matte. The converter matte is milled, non-magnetics are separated as solid nickel copper matte (NCM), and the magnetics are leached yielding a pressure vessel liquor (PVL). The remaining solid platinum group metals (PGM) concentrate after leaching is sent for downstream processing in the Precious Metals Refinery (Hofirek & Kerfoot, 1992). The work presented here is applicable to the base metals refinery which receives the two base metals feed stocks NCM and PVL. In 2009 the capacity of the refinery was upgraded from 21 ktpa nickel cathode plated to 32.4 ktpa. This paper deals with evaluating the capacity of the pressurised non-oxidative nickel leach (NOX) process which accounts for at least 28% of the nickel leached from NCM by design. The NOX design base requires two 80 m3 autoclaves divided into four compartments operated in parallel at 155°C and 600kPa(g). Elevated temperature is required to speed up the leach kinetics of particularly nickel and iron which are trapped in slow leaching mineralogical phases namely millerite and bornite, (Dinham, 2006). The stated equivalent capacity for the NOX configuration was 32.9 ktpa nickel plated at first pass nickel and iron leach efficiencies of 60% and above 80% respectively and is a key step for the selective removal of iron (Bryson, Hofirek, Collins, Stiksma, & Bereaowsky, 2008)."

Jan 1, 2017

By L. Tafaghodi, S. Sarbishei

"Following the depletion of nickel sulfide ores, laterites are considered as one of the main sources for producing nickel and cobalt. One of the primary steps in pyrometallurgical extraction of nickel from laterites involves partial reduction of the ore at temperatures below 1000°C. Studying the kinetics of laterite reduction provides valuable information on reducibility of nickel laterites using coal as a reductant. The present study investigates the reduction behavior of a nickel laterite by thermal gravimetric analysis and differential scanning calorimetry. Non-isothermal reduction tests and X-ray diffraction analysis were performed to find the main reactions that occur during the process. The kinetic parameters were calculated by Coats-Redfern method. The general model of simple reaction f(a)=(1-a)n was used for calculating kinetic parameters.INTRODUCTION Nickel (Ni) naturally occurs in the form of sulfide and laterite ores. Laterite ores are mainly available in tropical regions. Weathering phenomena during millions of years has led to the formation of several layers with specific mineralogy (Butt & Cluzel, 2013). The three main layers downward are limonite, smectite, and saprolite (Crundwell et al., 2011). Although laterites are the most available nickel ore resource (70%), their share in the overall Ni production is limited to 40% (Crundwell et al., 2011). The main reasons for not materializing the full potential of laterites are as follows (Ray et al., 1985): •,Laterite ores contain high water content (free and combined) which in turn results in high energy consumption of the extraction process. •,As Ni is present in the form of solid solution in laterites, physical upgrading methods such as flotation are not effective in increasing the Ni content before the extraction process. •,Extracting Ni from sulfide ores involve exothermic reactions which are beneficial due to decreasing the overall energy requirement of the process, however there is not efficient release of energy in the process of extracting Ni from laterite ores."

Jan 1, 2017

By B. Voyzelle

The deterioration of highway and bridge infrastructure has received considerable attention in recent years because of the billions of dollars needed for repair and rehabilitation. A major factor contributing to this problem is the corrosion of steel reinforcement. Reinforcing steels with good corrosion resistance and relatively low price are therefore essential for maintenance, cost reduction and service-life extension of the steel-reinforced structures. This article describes the development of low-alloying steels that offers good corrosion resistance with reasonably low cost. Topics include steel microstructures, mechanical properties, corrosion performance, industrial applications and economic aspects.

Jan 1, 2005

By G. H. Charlewood, J. W. McBean

"One hundred years after being developed, the diamond drill is still an essential tool in mineral exploration. The basic principle is unchanged, but the technique has been revolutionized, particularly in the past fifteen years. The cost of core drilling has not kept pace with the rising cost of living. The price of machinery, supplies and labour in drilling has doubled and trebled since 1946. Some of the techniques which have made it possible to hold the price line are described."

Jan 1, 1967

By G. J. Knighton

Introduction The Sullivan concentrator treats the complex lead-zinc-iron ore from the Sullivan mine of the Consolidated Mining and Smelting Company of Canada, Limited, to make a lead and a zinc concentrate for its metallurgical plants at Trail. Three miles separate the mine and mill, which are situated near the town of Kimberley, in the East Kootenay district of British Columbia. The orebody consists typically of banded sulphides, mainly galena, sphalerite, pyrrhotite, and pyrite. Important factors in the concentration of the ore are its exceedingly complex and its high specific gravity. It should be remembered throughout the paper that results and figures are based on Consolidated&apos;s experience with the Sullivan ore. The present mill feed rate is 8,500 dry tons of ore per 24 hours, for an operating week of five and a half days. Grinding and classification of the ore are carried out in three stages and, in addition, there is a re-grind section which re-treats the zinc middling. It is the purpose of this paper to discuss the classification in the various stages and to give the results o comparative tests which have been carried out for the purpose of improving operations in the mill. The Primary stage consists of six units, each made up of a ball-mill and classifier (see accompanying flow-sheet). Four units operate in open circuit and two in closed circuit. The secondary stage consists of eight ball-mills operating in closed circuit with twenty-one classifiers. In the Tertiary stage are two ball-mills in closed circuit with eight classifiers. The re-treatment section for re-grinding the zinc middling comprises one ball-mill in closed circuit with two classifiers.

Jan 1, 1947

By R. S. Douglas

Introduction During the past few years, a number of changes in the mine operations at Copper Mountain have taken place. The modernization and mechanization were necessitated and given impetus by wartime and other conditions, which were: (1) The urgent need for copper for wartime purposes. (2) The scarcity of skilled labour for underground work. (3) The increase in labour and supplies cost. (4) The necessity of finding ways and means of increasing the output per man-shift, because of the scarcity of skilled labour and the rising cost of labour. (5) The desire to increase safety measures, reduce the silicosis hazard, and aid mine ventilation. (6) The desire to improve the general working conditions in the mine for all workmen. (7) The desire to reduce the amount of dilution in the ore stream by a more selective yet highly productive method of mining. To this end, mining with diamond drills, and transferring broken ore with slusher hoists, appeared to be the answer to the problem. After considerable discussion and estimation of costs for comparison with those of the operation as carried on at that time, the proposed methods were tried out and, in practice, gave very gratifying results. Reference at this point is made to the paper written by C. H. Brehaut, W. N. Taylor, H. A. Shannon, and R. S. Douglas, which was published in the September, 1945, issue of Mining Technology, by the American Institute of Mining and Metallurgical Engineers, Inc., and subsequently in commercial mining journals. Since that time some improvements have been made in undercutting an orebody - the first through experiment and practice, the second through making use of the earth&apos;s barodynamic or gravitational forces. It is the purpose of this paper to describe and discuss these later developments.

Jan 1, 1947

By S. Joshi, E. Asselin

An electrochemical quartz crystal microbalance (EQCM) was used to study the leaching of pure gold in deaerated 1 M Na2S solution. Multiple cyclic voltammograms were measured between -0.76 and 1.242 V (SHE) at 20 mV/sec and 2 mV/sec and the frequency shift of the quartz crystal was simultaneously measured. Both the forward and reverse scans showed oxidation occurred between -0.40 to 0.20V. The frequency shift increased during both the forward and reverse scans in the potential range of -0.40 to -0.06 V indicating electrode mass decreased. Since at -0.40 to 0.20 V oxidation peaks were also observed, part of the oxidation was due to oxidation of gold. Eh-pH diagrams were constructed and showed soluble Au(I)-S(IV) species formed between -0.30 and 0.10 V (SHE). Atomic absorption spectroscopy of the test solutions and the mass change recorded by EQCM both showed about 0.015 mg of gold leached. Since the majority of the frequency shift increase corresponding to gold oxidation occurred at -0.40 to -0.06 V during multiple cyclic voltammogram measurement, the total leaching of gold could be approximated to occur at this potential interval to give a leaching rate of ca. 6.4x10-5 mg/s-cm2.

Jan 1, 2011

By R. W. Lawrence

"The management of acid rock drainage( ARD) to prevent impact when tailings are disposed of in the environment requires understanding of the phenomena giving rise to acidic drainage, a rigorous evaluation of the weathering characteristics of the tailings, and the successful implementation of control measures that will be effective in the long term. This paper provides a brief theoretical background to the complex reactions taking place in mill tailings containing residual sulfide minerals which must be appreciated to enable waste characterization program to be effective in predicting the future behavior of the tailings and in designing control methods which will work. The principals and practice of prediction and control as part of an ARD management strategy will then be discussed.Paper Not Available at Time of Publication"

Jan 1, 1997

By Omero Alonso-Gonzalez, Sergio Haro-Rodriguez, Ricardo Solis-Rodriguez, Francisco Alvarado-Hernandez, Juan Antonio Gonzalez-Anaya, Héctor Rene Vega-Carrillo

"Precious metals are currently associated with refractory minerals such as telluride (Calaverite, Sylvanite, etc.) and selenium (Naumannite Ag2Se), which are difficult to dissolve through traditional methods, therefore it is necessary to perform a pretreatment (oxidative or roasting) preceding the process of leaching by cyanidation. In this preliminary work the aim was to study the use of solvent extraction to remove tellurium and selenium ions from a synthetic cyanidation effluent, with the purpose of recycling the cyanide back to the process. For the extraction of these anions, TeO32- and SeO42-, tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (Amine F) were studied as extractants, using nonylphenol as a modifier in the organic phase (trimethylpentane). The results show that it is possible to recover 82% of selenium and 10% of tellurium from synthetic solutions containing either 20 mg/L Se or 20 mg/L of Te, respectively The Se or Te mole ratio to cyanide was 1:4.INTRODUCTION In relation to extraction of precious metals, the cyanidation process has been in use for over a century and despite environmental and toxicological problems it remains the most widely used and economical process available. In the late 90s, there were great efforts to recover gold and silver from refractory ores, which is difficult to do by simple cyanidation. To improve gold recovery from tellurides and selenides that occurs in some new mines, the ores are pretreated by roasting. This is one of the most effective ways of rendering refractory gold ores leachable as well as being a fast pretreatment process compared with bio-oxidation or pressure leaching (Aylmore, 2001). The most important tellurides minerals are Calaverite (AuTe2) and, Silvanite (Au, Ag)2Te4). In the case of selenides, minerals include Naumannite (Ag2Se) and Aguilarite (Ag4SeS) (Ostroumov et al., 1989). Examples of deposits containing telluride include La Bambolla Mine (Sonora, Mexico), Cripple Greek (Colorado, USA), and Kalgoorlie (Western Australia) (Aguayo et al., 1996). The main purpose of this work was to explore the feasibility of using quaternary ammonium salts such as: tallow trimethyl ammonium chloride (Quatarmina TPR) and hexadecyl trimethyl ammonium chloride (amine F) to extract tellurium and selenium anions from aqueous synthetic cyanidation effluents, so that the cyanide solution could be recycled back to leaching process. The tests were performed on synthetic solutions similar to those found in a mine: 20 mg/L Te as TeO32-, 20 mg/L Se as SeO42- and mole ratio to cyanide was 1:4. using an alkaline medium with pH ranging from 8 to 12. Two aspects are evaluated in this paper:"

Jan 1, 2017

By T E. Tibbetts

This paper deals with coal sampling in general and with mechanical coal sampling in particular. The necessity of obtaining representative samples is emphasized. Other sections of the paper are devoted to the design and selection of automatic samplers, with a consideration of the three main types, and the testing, operation and maintenance of these samplers. The cost of the installation of an automated sampling system must be related to the value of the material to be sampled, to the volume of coal involved, and to the savings in labour and economy which can be achieved. Introduction T HE Committee?:; on Coal Sampling of the Coal Study Subsection, Thermal Power Section (Eastern Zone), Canadian Electrical Association, was established in November, 1963, to "study the various problem areas of coal sampling." The first undertaking of the Committee was to at-tempt to survey the problem areas of coal sampling through an evaluation of coal sampling difficulties as experienced at both the plant design and operational levels within the electric utilities represented on the Committee. The results of this enquiry indicated that satisfactory answers to almost any conceivable

Jan 1, 1965

By Doug Russell

Natsource: At a Glance l 160 employees l Global reach ? New York, Washington, Calgary, Ottawa, Toronto, London, Tokyo l Major Environmental Commodity Broker ? Rated as Top GHG Broker (Environmental Finance Magazine Survey, Dec. 2000 & 2001) ? Leading RECs Broker ? Large Broker of SO2, NOx l Large Energy Broker ? One of Highest Volume Gas Brokers ? Major Electricity Broker Overview l International Market l Implementing the Rate-Based Proposal l Assessment and Management of Risk from GHG Emissions Limitations

Nov 1, 2002

Discovery of an economic diamond deposit produces considerable wealth in terms of jobs, royalties, mining investment, and economic spinoffs for residents, including Aboriginal peoples. Diamond mines contribute to the GDP, increased personal income per person and reduced unemployment rates. Is it possible in Alberta?

May 1, 2008

By J. R. Morris

"A hoisting plant design should satisfy two basic requirements:1. to provide the necessary materials handling capacity, including ventilation where applicable, while meeting the requirements of good practice and, as a minimum, government regulation; and2. to optimize the economics of the project. Selection of hoisting equipment to meet the first objective is a complex but logical engineering process. The necessary calculations of payloads, accelerations, speeds, rope strength, hoist size, and power requirements are very readily carried out on computers or programmable calculators. A variety of hoist options can be quickly examined to assess the effects of changes in design parameters.Meeting the second requirement involves balancing the costs of various hoist arrangements and shaft designs, together with the time cost effects of differing shaft sinking rates and potential advances to be gained by concurrent level development. The proposed mine layout is significant here, as is the possibility of future shaft deepening and/or production increase. The availability of used equipment may be significant, both as regards first cost and delivery time. The factors are interactive, with their relative effects .varying from project to project. This paper sets out the primary factors to be considered."

Jan 1, 1990

By M. Potesser

Higher prices for natural gas or oil have motivated the copper industry to reexamine the modes of oxygen and oxy-fuel burner usage at operating plants. With rising energy costs and the growing importance of environmental protection, burner usage and burner operations have become the focus of several investigations and optimization efforts. One possible approach to lower energy usage is through combustion using tonnage oxygen. When such oxygen is used, the flame temperature increases and operational efficiency is improved. As well, with the correct technology, due to the presence of lower levels of harmful substances such as NOx in the off gas, there is improved environmental performance. As regards copper production, furnaces are employed for both concentrate smelting or for melting and casting operations. The use of tonnage oxygen in concentrate burners for smelting provides for a higher thermal efficiency. For furnaces employed for melting, air-operated burners may in fact have an initial advantage because a long radiant flame is typically generated, thus providing for a higher degree of heat transmission. This paper describes the new experimental burner chamber of Messer Austria GmbH which provides for testing of the combustion of natural gas with oxygen or oxygen-enriched air and the use of special water cooling ducts that simulates a metal charge during melting, The operational effectiveness of the burner is determined from temperature and off-gas analysis data. The paper also discusses future trends in burner technologies including a new patented burner. Cu2007 - Volume III (Book 2) The Carlos Diaz Symposium ou Pyrometallurgy Edited by A.E.M. Warner, C.J. Newman, A. Vahed, D.B. George, P.J. Mackey, A. Warczok Toronto, Canada,

Jan 1, 2007

By Seungwoo Park, Whuisu Shim, Roe-Hoan Yoon, Kaiwu Huang

"A comprehensive froth model has been derived from first principles. It is based on predicting the kinetics of film thinning in the presence of particles of varying sizes and surface hydrophobicity. According to the Reynolds lubrication theory, the thinning of a horizontal film is driven by the excess film pressure (p), which is determined by the capillary pressure (pc) and the disjoining pressure (II). In the presence of particles, macroscopic capillary pressure (pc) is affected by the local capillary pressure (pc,local) in the vicinity of a particle and the number of particles in the film (N1,film), which in turn vary with the hydrophobicity and size of the particles. The Reynolds equation corrected for pc,local and N1,film is then used to predict the time (or froth height) at which a film is thinned to a critical rupture thickness (hcr), which in turn can be predicted using the Vrij’s capillary wave model (1966) after a modification to incorporate the contributions from hydrophobic disjoining pressure (IIhp). The model can predict bubble coarsening represented by the bubble size ratio between the top (d2,t) and bottom (d2,b) of a froth as functions of particle size and hydrophobicity, ? -potentials, frother dosages, froth height, gas flow rate, salt concentration, etc. The model predictions have been verified in experiments.INTRODUCTIONFroth flotation is regarded the best available technology today for upgrading minerals and coal fines. In the pulp phase of a flotation cell, air bubbles collect hydrophobic particles dispersed in it and rise to enter the froth phase on the top. Once in a froth phase, the bubbles coalesce with each other and become larger, resulting in a decreased bubble surface area. Under conditions of limited surface area, less hydrophobic particles drop off the bubble surface and return to the pulp phase. Thus, bubble coarsening provides a useful mechanism of increasing product grades. On the other hand, uncontrolled coarsening results in a decrease in bubble carrying capacity and hence throughput."

Jan 1, 2016

By A G. Rogers

This paper discusses the lubrication of surface and underground mining machinery and equipment from the standpoint of machine components. The machine components considered are bearings, cylinders, gears, chains, couplings, fluid drives, hydraulic systems, screws and wire ropes. The best selection of lubricants for these machine components, and for sub-divisions of the components, are outlined. They form general recommendations, for average operating conditions in both surface and under-ground mining operations. The American Petroleum Institute&apos;s service classification of both engine crankcase oils and gear oils is de-scribed and used in recommending products for these applications. The practical aspect of lubrication is kept foremost in the recommendations, which are designed to meet the requirements of a wide variety of equipment with the minimum number of lubricants. THE lubrication of mining machinery and equipment presents a variety of problems peculiar to the industry. The type of mine, the ambient temperature, water, dust, and operating and maintenance practices, as well as the age and condition of the equipment, are variables which have to be considered in making lubricant recommendations.

Jan 1, 1963

By A. G. Eccles

"INTRODUCTIONWestern Mines' copper-lead-zinc operations are located in Strathcona Provincial Park, near the geographic centre of Vancouver Island. This park includes Buttle Lake, which flows into the Campbell River water system. The latter provides domestic water for the Town of Campbell River, approximately fifty-eight miles from the mine site.Operation of the concentrator commenced in December 1966, at which time the tailings were discharged into a small tailings pond near the plant. On May 8, 1967 Permit No. 185 was granted to the company, allowing discharge of the tailings, through a submerged outfall, to the bottom of Buttle Lake.Needless to say, the concept of operating a mine within a park, and the discharge of tailings into Buttle Lake generated considerable controversy. However, this has all but been eliminated over the years by the proven effectiveness of Western Mines' pollution control program. In 1973 this program was further upgraded with the addition of an alkaline chlorination plant. Effluent treatment by this method became necessary as a result of process modifications, and has been effective in maintaining the levels of characteristics in the tailings within the ever increasing pollution control requirements imposed on the industry."

Jan 1, 1977