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By M. A. T. Cocquerel, M. G. Burcher, J. G. Eacott

"This paper is based on work carried out to examine the feasibility of increasing the smelting rate of two oil-fired calcine-charged reverberatory furnaces . Various constraints prevented physical enlargement of the furnaces and so allention turned to the use of preheated combustion air or oxygen enrichment to bring about the required increase in production. As a basis for further calculation, a furnace heat balance is determined using the smelting metallurgy and combustion data for the current operation. Various other operational data are tabulated and compared with similar data from other operating copper smelters.New heat balances are derived for various levels of combustion air preheat at the current smelting rate, and the effects of air preheat on oil consumption, combustion air and waste gas volumes are tabulated. These data are used to demonstrate the level of increased throughput which would be obtained before constraints in existing gas handling equipment are encountered.A similar exercise for oxygen enrichment is set out, with oil consumption, combustion air and waste gas volumes at various enrichment levels tabulated for the current smelting rate. These data are in turn used to demon strate the smelting rate which would be achieved at a practical level of enrichment before waste heat boiler and gas handling constraints are encountered.The energy implications for both cases are summarized."

Jan 1, 1980

By J. W. Matousek

Since the late 1800s, copper-nickel ores have been mined and smelted in the Sudbury area. The Canadian Copper Company, the Copper Cliff ancestor of Inco Limited, commenced operations with a blast furnace smelter in 1888. Coal-fired reverberatory furnaces were added in 1911 and multihearth roasters in 1914. The blast and reverberatory furnaces smelted, respectively, coppernickel ores and ore fines until 1930, when a milling process and plant began operating to concentrate and separate the minerals of these two metals. Two reasons for this delay were: (1) the availability of high grade ores suitable for direct smelting; and (2) the difficulties in making the copper-nickel separation. The Mond Nickel Company, however, practiced flotation at its Coniston Smelter site from 1914 to 1930. A bulk concentrate containing six per cent copper and five per cent nickel was recovered from ore of 1.6 per cent each of copper and nickel. Gravity (table) and magnetic concentrates were also produced. Inco Limited (then The International Nickel Company) began laboratory-scale flotation tests on its ores in 1918. This work led, ultimately (in 1930), to the construction of the 7500 tonne-per-day Copper Cliff Mill, designed to recover separate copper and nickel concentrates. Its capacity was expanded to 11000 tpd in 1936, to 18 000 in 1940, and to 27 000 in 1942. Since 1971 it has operated to process only the bulk flotation products from other mills to yield individual nickel and copper concentrates.

Jan 1, 1999

By Dharmendr Kumar, Pradip, Sivakumar Subramanian, Beena Rai, Venugopal Tammishetti

The separation efficiency in a mineral processing plant is generally assessed and reported in terms of elemental assays constituting the minerals of interest. However, different minerals comprising of same elements behave differently under similar process conditions. Thus, it is imperative to track the mineral composition thank elemental composition of different streams in a processing plant. The availability of automated mineral analyzers such as QEMSCAN and TESCAN in recent times has made it possible. However, due to the high cost and expertise required, their adaptation in day to day monitoring of operations is not yet a common place. X-ray diffraction (XRD) profile fitting (Rietveld Refinement) is another technique which can provide estimates of mineral proportions in a sample. The results of Rietveld Refinement however are affected by coating of fines on coarse particles, method of sample preparation, particle size distribution of sample, elemental substitution in mineral crystal lattice. In the present work, we propose a simple and efficient method for quantitative estimation of minerals in iron ores using elemental assays and thermo-gravimetry analysis data. The minerals (hematite, goethite, gibbsite, kaolin and quartz) are identified using powder XRD analysis. It is also observed that goethite contains Al substitution in the crystal lattice. The samples were analyzed for %Fe, %Al2O3 and %Silica using chemical analysis. The measured Loss on Ignition (LOI) in the sample is contributed from goethite, gibbsite and kaolinite phases. LOI from gibbsite and goethite occur in temperature range 250–350°C and LOI from kaolinite occur in temperature range 400–700°C. According, LOI are determined in two different temperature ranges that are 100–400°C and 400–850°C. We have used the data to successfully determine the mineral compositions of iron ore samples. We have also employed a data reconciliation algorithm on the calculated data for further improvement and consistency of our results. Our method is very convenient for quick estimation of mineral proportions in a sample. The proposed method can also be used for quantitative phase estimation in bauxite ores and red muds.

Jan 1, 2016

By K. H. Singh, J. N. Szuck, J. A. Riddell

"Hydraulic rock drilling equipment has been in use at Falconbridge over the past two years in both production and development situations. This paper deals with the experience gained in the application of hydraulic drilling in the company's mines and discusses the benefits and problems encountered during their use. The paper primarily focuses on technical, operating, maintenance and economic aspects of the machines, and does not attempt to compare the performances of different machines from the various manufacturers.IntroductionThe Sudbury Operations of Falconbridge Nickel Mines Limited are comprised of five operating mines and two mines under development. All the production comes from underground mines, mostly at depths below 1000 metres. The company, faced with increases in operating costs and difficult mining conditions, has continued to seek solutions with the help of new mining technology.The development of electric-hydraulic drilling machines in Europe had been pursued with great interest and, in 1979, a decision was made to test these machines to prove their technical and economic viability under operating conditions. Since then, a number of electric-hydraulic machines have been evaluated in different situations and currently nine hydraulic machines are being used in the company's various mines. These machines are comprised of two-boom drilling jumbos for development, one-boom machines for longhole drilling and a large-hole-diameter drilling rig for blasthole drilling. One hydraulic jumbo has also been used in a cut-and-fill stope."

Jan 1, 1982

By Parsons. Robert B.

"Starting this year, corporations that conduct business in Ontario face a new tax a corporate minimum tax. This tax is in addition to the myriad of other taxes that make up a corporation's total tax burden including federal and provincial capital 1oXJ!S, payroll tax and sales taxes. Mining companies with gross revenues in excess of $10 million or total assets exceeding $5 million may be liable for this new tax. IntroductionOn December 8, 1993, the Ontario government introduced legislation to implement the corporate minimum tax (CMT promised in its May, 1993 budget. There are very few differences between the final legislation and the budget proposals.The CMT is effective for taxation years commencing after 1993. Subject to certain specific exemptions (detailed below), the tax applies to all corporations liable for Ontario Corporate Income Tax that have either gross revenues in excess of $10 million or total assets in excess of $5 million. These measurements apply to the aggregate gross revenues and total assets for all corporations in an associated group and a corporate partner's share of partnership assets and revenues must be included in the determination.In essence, the CMT is an income tax that is based on financial statement profit instead of an income amount that is determined separately under a statute. Accordingly mining companies (including so called ""junior"" exploration companies), which traditionally sheltered their taxable income by claiming generous exploration and development deductions, could find that they have a CMT liability."

Jan 1, 1994

By A. Aaltonen, S. Paloranta, H. Myllykangas

A property based dynamic model of flotation was built and validated for training purposes. The model is based on the work of the AMIRA P9 project. The recovery of each particle with composition and size is calculated in a given simulation step. The model takes into account machine and operational parameters such as air flowrate and froth height. The model was created using fullscale test data on Pyhlisalmi Cu-Zn-pyrite ore with flotation kinetics of multiphase particles determined. Simulation and validation shows that model can predict the dynamic behavior of the process accurately enough for training purposes.

Jan 1, 2009

While this paper is directed towards the ?Bellambie? type of rope attachment, the principles can be applied to any brand of rope fitting however, it is a only a broad outline and the specific installation and maintenance procedures can be obtained from the attachment supplier. The types of attachment to be discussed are:- ?Thimble Type rope cappel ?Wedge Type cappel ?WRC Rope Clamp ? (Rope Glands) ??Hoist and Balance Rope Sockets In each case, the assembly and stripping (disassembly) plus the basic maintenance procedures is briefly described. A guide for Risk Assessment is also included but because of his familiarity with the installation, the end-user is in the best position to draft the final version.

May 1, 2003

By John De La Vergne, Morri Medd

"This paper describes the sinking of a circular concrete ventilation shaft through 110feet of water-bearing overburden. The brine circulation freezing method was used to stabilize the walls during excavation. In order to take advantage of the cold winter weather, a custom-built heat exchanger (natural radiator) was installed in place of the standard mechanical refrigeration plant.IntroductionIn the late fall of 1979, Les Mines Selbaie awarded a contract to the firm of 1.S. Redpath Limited to sink a ventilation shaft on its property in northwestern Quebec. The shaft was to be sunk through 110 feet of water-bearing overburden and approximately 90 feet of rock to a final depth of 200 feet below surface. The water table was measured at 16 feet below the surface elevation.After examining the soils report and diamond drill core from the shaft area, Redpath came to the conclusion that freezing was the best way to stabilize the overburden for sinking. LocationThe mine site is 420 statute miles due north of Toronto, just east of the Ontario/Quebec border (Fig. 1). Access to the site is provided by a development road built by the Quebec government from the Matagami/lames Bay Highway. History of Ground Freezing In the Mining IndustryIn 1862, shortly after the development of mechanical refrigeration, a mine shaft was sunk through an artificially frozen water-bearing formation in the United Kingdom. The first application of ground freezing in North America was for a Michigan iron ore shaft in 1888. Since that time, the freezing method has been used to sink hundreds of shafts throughout the world. Its best known application was to sink sixteen shafts through the Blairmore Formation in Saskatchewan.The same method has been used in every case. It involves chilling a calcium chloride brine solution and circulating the brine in concentric pipes, spaced between 3 and 6 feet around the shaft perimeter and usually 4 to 5 feet from the limits of the proposed shaft excavation."

Jan 1, 1982

Diverse and considerable energies are associated with mobile equipment operated and maintained on mine sites. Loss of control of these energies is a common cause of injury on mine sites and this is well recognised by the mining industry. In 2006, 4 multi-national mining companies formed the Earth Moving Equipment Safety Round Table (EMERST), with the aim of engaging collectively with the manufacturers of equipment to accelerate improvements in mining equipment design. Originally focused on surface mining equipment, and particularly haul trucks, the focus of EMESRT widened to include underground and exploration equipment. Since 2006, EMESRT has maintained a program of regular visits and other engagements with a steadily increasing number of manufacturers. The membership of EMESRT has also increased, with 15 companies being members in 2012. An initial step undertaken by the EMESRT members was the development of ?Design Philosophies? which drew of the collective experience of mining companies to identify potential unwanted events which cause equipment related injuries and illness. A technique for analysing risks associated with operation and maintenance tasks, the Operability and Maintainability Analysis Technique (OMAT), was subsequently developed and trialled. In 2011, the EMERST members resolved to propose a common form of safe design information to be requested by all members companies during procurement, and the resulting EMERST Design Evaluation for Equipment Procurement (EDEEP) process was launched at MINExpo in Las Vegas in September 2012. The outcomes of OMAT risk assessment and control activities are integrated during this process into a common ?Safe Design Information? template for communication to prospective purchasers. The aims of requesting manufacturers to follow this process are to provide equipment purchasers with a common way of assessing how well the issues in the EMESRT Design Philosophies are addressed in the equipment design; and to provide manufacturers with additional information for use during equipment design. The process involves identifying priority tasks based on frequency and the severity of the consequences of potential unwanted events identified in the EMESRT Design Philosophies; undertaking a task-based risk assessment of priority tasks in conjunction with site-based personnel; evaluating the effectiveness of control measures; and providing information about safe design features in a standardised format.

Aug 1, 2013

By Tyson Birketi, Françoi Robert, Steve Green, Dan Richardson

Detailed sampling using a portable diamond drill, and inter laboratory comparison of selected samples have been combined with statistical studies of truncated populations to establish the gold content of several outcrops in the Val d'Or area. The outcrops chosen are non-mineralized. The background gold concentration in the rocks of the region is 5 ppb or less. Gold is distributed relatively homogeneously within the outcrops studied except for slightly increased concentrations within quartz-tourmaline veinlets. Three samples, of which 20 grams of powder are analyzed for each, can adequately determine the gold concentration of a structurally simple outcrop in the Val d'Or area.

Jan 1, 1992

By N. Ahern, L. Manoukian

"Cyanide is a leaching agent for precious metals commonly used in gold ore processing. Cyanide exists in various forms (including free, complexed as weak or strong complexes, and as ions such as cyanate and thiocyanate), so its detection, speciation and analysis in processing or environmental samples can be complex. This paper will review best practices for cyanide sampling and preservation in the field, interferences and pretreatment methods required prior to sample analysis and analytical methods that are used for cyanide species. Titrimetric, flow injection ligand exchange, spectrophotometric, colorimetric, potentiometric, amperometric, and chromatography techniques will be discussed and their chemistries, detection limits, advantages and limitations will be described.INTRODUCTION Cyanide is well known to be an extremely toxic species. Accurate cyanide measurement in effluent from mines is critical from an environmental perspective. Its measurement is also an important control parameter in the recovery of gold using cyanidation. Cyanide chemistry is diverse and complex, and cyanide analysis can be challenging as a result of and because of limitations in understanding of analytical methods. Various chemical mechanisms can form or destroy cyanide, and the sample matrix or preservation chemicals can also affect analytical results. These interferences make the collection of reliable cyanide measurements challenging and can start as soon as the sample is collected, during laboratory pre-treatment and during analysis. This paper reviews different methods of cyanide measurement. The basic chemistry of cyanide, best practices for sampling and preservation, as well as various methods of analysis will be discussed.CHEMISTRY The complexity of cyanide chemistry is well known (Beck, 1987; Delgado, Botz, Bucknam, Milasovljevic, & Staley, 2008; Botz, Milosavljevic, & Ward, 2013) and is attributed to the ability of cyanide to undergo: •,Volatilization •,Precipitation •,Adsorption •,Complexation with metals •,Oxidation to cyanate, ammonia, or cyanogen chloride •,Reaction with sulfur or sulfide minerals to form thiocyanate •,Redox reactions leading to the formation of cyanogen and cyanate •,Redox reactions (of some cyano complexes) •,Photochemical reactions (of some cyano complexes)"

Jan 1, 2017

By Bryan Tisch

Goal of GMGE ??To advance mine reclamation through the beneficial use of organic residuals for the sustainable establishment of bioenergy crops and other productive land uses Objectives ??To advance the current ?standard? of mine reclamation by demonstrating that mining lands can safely become agriculturally ?productive? through the use of organic residuals. ??To generate and compile sound scientific data that can be utilized by stakeholders to better assess the environmental impacts of utilizing these materials. ??To complete a manual of best practices regarding the utilization of organic residuals on mine lands. *Considerable effort to be placed on operations/implementation side of utilizing residuals ?rather than just pure research

May 1, 2011

By Jorge Lema Patino

"The purpose of this paper is to determine the best techno-economic alternative for the treatment of tin ores, when comparing the various mining and metallurgical methods of preconcentration, concentration, volatilization (fuming) and up to the final stage of selling to the smelter. The study of the influence of the different parameters of cost, recovery and quoted prices has motivated the paper, which aims at determining the best process of ore treatment in terms of its techno-economic feasibility.Method of WorkOn the basis of head grades of 0.5, 0.75 and 1.0% tin, the following alternative methods of treatment are possible:1. Mining-Concentration-Smelting.2. Mining-Preconcentration-Fuming-Smelting.3. Mining-Concentration-Separation, with direct smelting and fuming/smelting of the two fractions produced.The calculations were carried out on the basis of existing information and publications concerning the various experimental recoveries in the operating mills of COMIBOL. In the case of concentrates containing less than 10% or more than 40% tin, extrapolation was required.The final grade of the tin concentrates and the gross weight of the concentrate were calculated on the basis of the estimated recovery curves. The costs of the preconcentration and the concentration stage s were determined per gross metric ton of material treated.The calculation of the cost of the smelting stage is similar for all the alternatives, the royalties and smelting charge varying with the grade of the final concentrate. In the fuming stage, a uniform recovery of 90% was taken in all cases so as to obtain a final concentrate grade of 65% tin, regardless of the head grade of the feed material.For the separation stage, the following considerations apply:a) Separation can be carried out by gravity separation or flotation methods.b) The cost of separation varies depending on the system used.c) The distribution of tin in the two fractions is 100% at this stage. In other words, there is no loss of tin during separation."

Jan 1, 1982

By Mousa Mohammadi

Due to operational advantage of dragline in simultaneous excavation and back-filling, the equipment has gained vast importance in open-pit mining. Besides, absence of auxiliary haulage units and a myriad of other benefits are also credited in favor of excavation of muck piles by the draglines. However, the aspects of production, productivity and economics are of utmost significance in dragline operation and planning. In this light, the present paper is an endeavor to analyze availability and utilization of dragline operations. The paper presents a good amount of data for 4-draglines operating in one of the major opencast projects in India. The study reveals the trends of availability and utilization of these draglines during last 11-years. Furthermore, the study also highlights the salient reasons for loss of available hours and for idling of the draglines. Some startling information and facts have been illustrated in form of graphs and pie charts.

Aug 1, 2013

By Frank Ebbutt

Introduction The property of the Britannia Mining and Smelting Company, Limited, is situated on the east side of Howe sound, about six miles from its head. It is roughly thirty miles by water from Vancouver, one of the important ports of the Pacific and the industrial and financial centre of British Columbia. Howe sound is navigable for ocean-going vessels and Britannia Beach is a daily port of call for the commodious boats of the Union Steam-ship Company, sailing from Vancouver. Few mines are so ideally situated or have so many or varied natural advantages. Copper was first found on Britannia mountain in 1888, by Forbes, but it was not until 1898 that five claims were staked here by Oliver Furry, a trapper. It is from these claims that the major production during the past thirty years has come. In 1900 the Britannia Copper Syndicate was formed and development of the property was commenced. In 1903 the late Grant B. Schley obtained control, and through his efforts the Britannia Mining and Smelting Company was organized in 1908 as a subsidiary of the Howe Sound Company. Since that time, a persistent and progressive policy has been followed, which has resulted in a prolonged and profitable operation. The country in the immediate vicinity of the mine is marked by strong relief, with mountains rising abruptly from tide-water to elevations of 5,000 feet and more. Two broad transverse valleys deeply dissect the area. These are the valleys of Britannia creek and Furry creek. The region has under-gone prolonged and relatively recent glaciation. Over much of the surface there is deep overburden and dense vegetation. The geology of the mine and vicinity has been described in reports by S. J. Schofield (1), H. T. James (2), J. G. Barry, and others (3). The present writer is in accord with much of this literature on Britannia, but during recent years, extended observations made underground have shown that the 'quartz porphyry', or 'mine porphyry', of several of the earlier writers is not the host rock to the commercial mineralization; and he contends that the mineralization occurs in highly altered phases of a complex series of ruffs, flows, and pyroclastics and their autoclastic metamorphosed products.

Jan 1, 1935

By L. Long

Stirred milling of nickel laterites offers possibilities for improving liberation and selective size reduction of soft nickel-bearing minerals in laterites. Batch grinding tests were performed in a Netzsch LME4 stirred mill on siliceous goethitic (SG), goethitic (G), and saprolitic (SAP) nickel laterite samples (- 2000 ?m particle size) to evaluate the effect of stirrer speed, solid content, water salinity and grinding time. A fine mineral product (-38 µm) was used to evaluate the effect of selective grinding and Ni upgrade. The optimum grinding time for the highest Ni upgrade was 0.25 min, 0.1 min and 0.1 min for the SG, G, and SAP nickel laterite, respectively. A new feed (38-2000 µm) for each nickel laterite sample was prepared for batch grinding tests under the optimum grinding conditions. Upon grinding the 38-2000 µm feed, the - 38 µm product confirmed the effect of selective grinding and nickel upgrade. Size classification followed by stirred milling is a suggested process for Ni upgrade. The best Ni upgrade result was achieved on the SG nickel laterite among the three samples. The Ni grade increased from 0.85% to 1.37%, with 27.8% Ni recovery. Bottle roll leach tests showed that for SG and SAP samples selective grinding had no dramatic effect on Ni extraction due to the slow leach rate of hard mineral particles. Stirred milling of G sample increased the surface area of goethite, resulting in higher Ni extraction. Gravity concentration through a Knelson Concentrator was not effective in the further treatment of the stirred milling products either due to the poor operating conditions or due to the mineralogy characteristics of the feed samples. The energy requirement in the stirred milling was investigated. The first pass of the signature plots study is critical for the purpose of selective grinding, because the best result on selective grinding is achieved in the early stage of the grinding process.

Aug 1, 2013

By Jinsuo Zhang

Investment in coal resource development is affected by a variety of uncertain factors. Investors can make a flexible, strategic decision to achieve the value of risk implicated in those uncertain factors. Therefore, based on real-option theory, we identified key uncertain factors that affect a coal resource investment project, and revealed the formation mechanism of option value in coal resource developing investment project. Then, a multi-factor decision making model was established for a coal resource development investment project with random changes of coal price, interest rate, convenience yield and production cost. Finally, we tested the model and analyzed relevant parameters by applying living data. Our results indicate this model reflects the value of risk implicated in uncertain factors for coal resource development investment, and is able to determine a critical point of decision making change when coal price and production cost varym respectively. By means of parameters analysis, the convenience yield has a positive effect on the project value. The interest rate has a negative effect.

Aug 1, 2013

By A. Dave Mackintosh

Historical closure data has provided a description of the stress distribution patterns occurring around mine openings and enabled the development of a time ? distance plot predicting the location of the stress peak and its migration away from mine openings with time. Data collected from active mining areas during the 1970?s and 1980?s indicated the peak appeared to stabilize approximately 135m (450 ft.) from openings after four years. The region of high load and accompanying poor ground conditions in which the peak was centred was spread over approximately 45m (150 ft.) to 60m (200 ft.). Recent data from new development headings cut adjacent to 25 year old extraction areas suggests load transfer takes place over a much greater distance and time frame than predicted.

May 1, 2001

The problem of thin and very thin coal seam extraction in a long perspective of Ukraine?s fuel and energy industry development was determined. Technical and economic benefits of coal seams selective mining technique including beneficial environmental impact were substantiated. The scientific and practical aspects of development of borehole underground coal gasification (BUCG) technology are considered. The technological scheme of underground gas generators is offered on the basis of the authors? criteria of fitness and adaptability to the mine and geological conditions. These charts foresee the preparation of gas generators from earth surface and directly from the present mine working by inclined horizontal boreholes. Basic research is directed at abandoned supplies extraction in coal mines. Concepts of technological decisions and technical implementation of the underground part of the gasification system are worked out with analytical models, with subsequent test verification on special options and a mine experimental gas generator. Forming the technological scheme of gasification is founded on the basis of tying up spatial and sentinel factosr of coal seam gasification taking into account sufficient impermeability of the system a «gas generator ? rock massif» and to dirigibility by thermochemical processes that flow in a rock massif. The offered solutions contain the possibility of creation of the power and chemical enterprises of gasification, taking into account the complex use of BUCG products in the ecologically reserved technological cycle. Gas generator efficiency is evaluated from an economic standpoint.

Aug 1, 2013

By R. L. Brown, E. A. Swanson

THE Buchans ore bodies are located in central Newfoundland, three miles north of Red Indian lake. The townsite of Buchans was named after a Royal Navy Captain who, while attempting to make contact with the Beothuck Indians, camped in the area in 1820. Ore was first found at Buchans by a Mic Mac Indian, Matty Mitchell, who discovered one of the three small orebodies in the bed of the Buchans river. The Anglo-Newfoundland Development Company, which holds mineral rights in the area, developed the orebody, but was forced to give up the venture because of difficulties encountered in separating the various sulphides. The American Smelting and Re-fining Company developed a flotation process which was capable of economically separating and concentrating the various sulphides, and, in 1926, they took a long-term lease on the property.

Jan 1, 1962