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By Tim O’Neil

Question: Looking forward, do we face a future in which energy markets, energy policy and energy conflicts threaten to preoccupy, if not dominate, our concerns over economic growth, national security and domestic tranquility? The answer is, we may indeed face such a future. Question: What oil resource is comparable in size to the reserves of Saudi Arabia and presents a tremendous opportunity? The answer, the oil sands in Alberta, Canada. Question: What is the largest mineral staking rush in North American history, still under way? It has so far led to the development of two large mines. The answer is the Point Lake diamond strike in Canada’s Northwest Territories. It led to the development of the Ekati and Diavik mines.

Jan 1, 2004

By P. Dennis, T. Pieters, A. De Kievit, S. Ganguly

TEMCO has been producing manganese ferroalloys in submerged arc electric furnaces for over 40 years. The furnace linings all along have been of conventional insulation type until 2001 when a freeze lining of UCAR concept was installed for a 20 MW Furnace. Continuous improvement of furnace lining performance has been a key component in improving the business competitiveness of TEMCO. The expected minimum campaign life of the freeze lining is fifteen years as compared to the ten years of the conventional linings. The success of the freeze lining is very critical to the quanta and direction of heat flow through the lining that control the freeze protection. Under freeze protection can lead to reduced lining life and over freeze protection, on the other hand, can lead to operating difficulties and loss of smelting efficiency. It was, therefore, necessary to develop a computer based system to monitor and control the freeze protection. The computer based monitoring and control system uses the basic principles of heat transfer, activeX object and heat flux from dual thermocouples and that is reviewed.

Jan 1, 2004

The SFR system utilizes a skimmer or extractor placed at or near the slurry-froth interface where there is a higher concentration of valuable mineral particles. With assistance of hydrocyclones, it is possible to classify the extracted particles into coarse and fine particle streams, that can be handled separately. It also allows the coarser solids to be separated from entrained low-value fines. The first test results with the SFR system significantly improved both coarse and fine particle recovery in a flotation cell. The SFR system was tested in the flotation circuit at a copper-moly concentrator, and the results show that the use of the skimmer has huge potential to increase the froth recovery (Rf) of both molybdenum and copper.

Jan 1, 2012

By K A. Bunker, A D. Campbell, E Ah Mu, A R. Penney

The Ernest Henry mine is a transverse sublevel cave (SLC), which is relatively unique due to the 45 degree inclination of the orebody. To economically recover ore, each sublevel is horizontally offset from the previous level by around 25 m, depending on the orebody geometry. Mine development, slotting and initial production within this zone occurs in a high stress abutment that increases in magnitude at depth. These areas are seismically active and close to the hanging wall where cave propagation is yet to initiate. High stress conditions and the close proximity to the cave seismogenic zone results in challenging geotechnical conditions in the step out zone of each level and requires management of hazards including stress driven rockfalls, rock bursts and pillar failure.This paper outlines how these hazards were forecast using numerical modelling and geotechnical monitoring. Risk management techniques included dynamic ground support design, development of a new mine layout and extraction sequence as well as delayed re-entry into seismically active areas. Ongoing monitoring, instrumentation measurements and field observations were used to track the effectiveness of the controls.Future production levels are forecast to experience increasing stress and seismicity, which will increase demand on excavations and installed ground support. Ensuring the techniques and controls for monitoring, measuring and mitigating stress and seismic hazards are enforced is essential for continued safe production.CITATION:Campbell, A D, Bunker, K A, Ah Mu, E and Penney, A R, 2016. Managing stress and seismicity in an inclined sublevel cave, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 319–328 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Ian Vaz, Takefumi Takuma

"The New Orleans area has been repeatedly flooded by major storms and hurricanes since its French colonial era. After severe flooding in May 1995, the U.S. Congress authorized a massive flood protection project called the Southeast Louisiana Urban Flood Control Program (SELA) in 1996 to improve interior drainage in Orleans, Jefferson, and St. Tammany parishes. However, the project was not fully funded before the landing of Hurricane Katrina in 2005 and Hurricane Rita, which breached many of the area’s levees and flooded 80 percent of the city. Finally, the project was fully funded in 2008 and has been worked on towards its 2017 completion. Another large project simultaneously worked on in the area is the Hurricane and Storm Damage Risk Reduction System (HSDRRS). This system was designed for a 100-year level of flood risk reduction. One particular project within the HSDRRS rendered successful due to an unconventional method of pile driving that was utilized to install sheet piles to reinforce an existing concrete I-wall. This paper will discuss how and why this non-vibratory method of sheet pile installation allowed the project to be successfully completed ahead of schedule.INTRODUCTIONSteel sheet piles were utilized on many of the SELA and HSDRRS projects for permanent cutoff walls under concrete I-walls or T-walls or for temporary earth retaining walls of drainage structures. Although the SELA Project was established in 1996 after severe flooding the year before, hardly any work was done on it until the two catastrophic storms Hurricanes known as Katrina and Rita triggered its revival. These two hurricanes also triggered the HSDRRS soon after the storms’ devastation. The SELA project authorized to improve interior drainage systems while the HSDRRS project was authorized to raise or restore levees and floodwalls mainly along Lake Pontchartrain, the Mississippi River, and Lake Borgne in addition to other areas. Figure 1 shows the SELA Projects that have been completed, are still under construction, or approved for construction. The projects fully highlighted in yellow within the map specified the press-in piling method. These improvements included drainage systems, pump stations, surge walls, and outfall canals as enhanced protection for future storms similar to Hurricane Katrina that caused so much damage by inundating the New Orleans area in August and September 2005 respectively (Facts and Figures, 2012). The completion of these projects were the responsibility of the U.S. Army Corps of Engineers, New Orleans District.Due to the fact that many of the projects were in densely populated areas, the Army Corps of Engineers specified a non-impact, non-vibratory press-in piling method for driving and extracting sheet piles for many of the projects to mitigate noise and vibration impacts. The soft soil conditions in the New Orleans area was also a contributing factor in the Army Corps of Engineers’ decision to specify this piling method due to the risk of settlement for existing historical as well as modern structures. In addition, there were other projects that elected to use the press-in method without any contractual requirements. One of these projects was the Inner Harbor Navigational Canal Reach II Emergency Interim Repair which was part of the HSDRRS project that has been under construction since its authorization in 2005 (Facts and Figures, 2012)."

Jan 1, 2017

By E. Chin

The only economically significant mineral exploited in Banglades - during 1981 was natural gas. Nitrogenous fertilizer production was important to the agricultural sector and was totally dependent on the natural gas for fuel and raw material. Domestic cement plants were also fu pled by natural gas. The flat river-delta terrain for most of Bangladesh makes the potential for discovering major mineral deposits poor. No large deposits of metal ores have been found and only in the small hilly southeastern section of the country is there even much chance of finding any. Heavy mineral sand deposits may eventually be exploited along the Chittagong coastline. There is a good potential for crude oil discoveries. The Bangladesh economy has been heavi¬ly subsidized by billions of dollars of foreign aid since the country's inception. A World Bank report recommended total aid needs of over $2.6 billion in fiscal year (FY) 1980-81. It received commitments for barely over one-half that amount.

Jan 1, 1983

Raw materials account for over 60 per cent of the cost of hot metal production in classical blast furnaces and the principal cost component is cost of coke. Dependence on coke is a traditional weakness of blast furnace ironmaking and while efforts have been made to evolve alternative ironmaking technologies which do not use coke, such as direct reduction, smelting reduction, and the more recent method of making iron carbide, blast furnaces continue to be the most efficient means of producing bulk hot metal even today. Coal injection, to the extent of 150 - 200 kg/t of hot metal, has been one of the major innovations made in blast furnaces to decrease cost and to reduce the dependence on coke. This has, however, given rise to more stringent coke property requirements (which often means more expensive coke) - a `tail spin' of Sorts!

Jan 1, 1999

By Erkan Bayrak, Serkan Erkara, Ozkan Duzgun, Ekin Gungor

This paper presents part of the outcomes of the drill and blast optimization project carried out at Kisladag Gold Mine in Turkey. Kisladag Gold Mine is the largest gold mine in Turkey with a low-grade, bulk-tonnage, open pit operation that uses heap leaching for gold recovery. After blasting, the ore is fed to a three-stage crushing circuit which prepares crushed ore approximately -10 mm (0.39 in) for heap leaching. Crusher downtime analysis showed that blocky material and insufficient feed are causing significant downtimes with the primary crusher. This was supported by the fragmentation data collected to date. It was decided to initiate a fragmentation project to understand the variation in the run-of-mine (ROM) size with a view to provide a consistent feed to the crushing circuit. The study includes the analyses of the ore strength and structure, image analysis of the fragmentation pictures acquired from blasts, blast auditing and quality assurance and quality control (QA/QC) analyses. During this project, over 200 fragmentation pictures were acquired from 47 blasts to optimize ore and waste blasts. Ore strength varies between 30 and 120 MPa and rock quality designation (RQD) ranges between 30 and 100. A site-specific fragmentation model was used to calibrate the fragmentation for blast domains formed. In addition, alternative cases were simulated to achieve blasts designs with consistent ROM fragmentation size distribution. Alternative blast designs that include stemming length and powder factor changes were suggested. Long stemming length, drill cuttings use, free faced blasts, small shot sizes and poor stemming length control were some of the key issues causing coarse fragmentation.

Jan 1, 2015

By J. M. Galera, M. D. Rodriguez, V. Pozo, S. Cooper

"Cobre Las Cruces mine extracts copper minerals from a VMS deposit located in the well-known Iberian Pyrite Belt (IPB). As an open pit, it is distinguished geologically from other IPB mines by the presence of around 150 m of Tertiary soft marls, known locally as the Guadalquivir Blue Marls, followed by a regionally important aquifer. Below the marls and aquifer the mineralization is hosted by rocks typical of the Palaeozoic within the IPB, comprising gossan, tuffs, slates, and sulphides.This combination of a substantially soft rock and more competent, older (but still occasionally problematic) Palaeozoic lithologies constitutes a unique geological framework and presents substantial challenges in maintenance of slope stability, and therefore operational safety, at the mine site. This paper describes the fundamental design, excavation, and monitoring measures implemented at the mine to maintain safe production, and the lessons learnt during the mine development. IntroductionAs a modern Spanish mine, Las Cruces is committed to the use of best available technology and practices with the aim of guaranteeing the production of ore in a safe environment. From a practical perspective, this implies the realization of a high quality pit design, ongoing geotechnical mapping of exposed slopes to ensure conformity with design, and use of leading geotechnical surveillance technology to complement visual observations. The focus of this article is to illustrate how, at a mine site with potentially problematic soil/rock conditions, multiple advanced techniques employed from design stage analysis through to final pit configuration and vigilance, were combined to achieve an overall control of the ground conditions. In Figure 1 the layout of the pit is shown, illustrating development at the beginning of 2015."

Jul 1, 2019

By M Bird, B Oats, M Sganzerla

Mining operations are continually aiming to reduce operating costs to improve plant profitability. One way in which the Cannington operation sought to achieve this was by increasing the wear life and reducing the energy consumption of their flotation mechanisms. This was made possible using Outotec’s FloatForce mechanism. The FloatForce mechanism has been developed by Outotec over a six year period involving both CFD modelling and rigorous site testing. FloatForce delivers improved air dispersion and cell agitation efficiency; as such it can be operated at lower rotor tip speeds when compared to Outotec’s previous mechanism.Cannington trialled three FloatForce mechanisms in a train of ten OK38 zinc roughers. The mechanisms’ rotational speed was reduced by 10% compared to the previously installed MultiMix mechanisms. The purpose of the trial was to quantify the energy saving and assess whether there was any reduction in plant metallurgical performance.The trial was successful with FloatForce delivering a 17% reduction in power, an improvement in wear and improved recovery. Analysis of pre and post-installation metallurgical accounting data showed the following:The FloatForce installation resulted in a recovery increase of zinc to zinc final concentrate of 0.4 – 4.0%*The FloatForce installation resulted in a recovery increase of lead to zinc final concentrate of 0.0 – 0.3%*There was no statistically significant change in silver recovery to zinc final concentrate that can be attributed to FloatForce**95% confidence interval (CI) using multiple linear regression models.The Cannington operation is now in the process of further optimizing its power consumption and wear savings by changing the remaining OK38 zinc and lead rougher float cells to FloatForce mechanisms.CITATION:Bird, M, Oats, B and Sganzerla, M, 2015. Improvements in flotation cell maintenance, power consumption and operation at South32 Cannington, in Proceedings MetPlant 2015, pp 230–245 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By E. S. Moore

Although nickel was in use in alloys long before the Christian era, the metal was not discovered until 1751, when Cronstedt recognized it in niccolite from Sweden. The Chinese apparently used a nickel alloy, known as "pahfong" thousands of years ago and Persian coins dating farther back than 200 B.C. consist of a copper-nickel alloy similar to some of those now in use in coins. The pure metal was first prepared about 1775 and the metal was refined for commercial purposes some years later. The nickel industry did not attain much prominence until the ores in New Caledonia were discovered. Exports of ore from that country began in 1875 and since that date there has been an ever-increasing world output of nickel and a great expansion in the uses of the metal except during short periods of commercial and industrial depression. Previous to 1875, for a number of years, Norway was the chief producer, although the metal was mined also in Sweden, Finland, Italy, Germany, Austria, France, China, the United States and other countries. With the discovery of nickel deposits in the Sudbury district, Ontario, a new factor was introduced into the nickel industry and Sudbury has since become the overwhelmingly dominant feature in the world's nickel markets. Although nickel was first discovered in Canada as early as 1848 near the north shore of Lake Huron and nickel-copper sulfides were found in 1856 by surveyors working close to the present location of the important rnine at Creighton, in the Sudbury field, it was not until 1883 that any importance was attached to this field. In that year copper sulfide attracted attention where the main line of the Canadian Pacific railroad was being projected across Canada to the Pacific coast. Mining began near this discovery in 1889 but in the meantime operations had begun in 1886 in other parts of the field and by 1890 about 100,000 tons of ore had been raised. In the Sudbury field, as in Norway and at the old Lancaster Gap mine in Pennsylvania, the ore was first mined for its copper content and difficully in the refining of the copper led to the discovery of the important proportions of nickel in the ore. No. 3 property of the International Nickel Co., now known as the Frood, the greatest deposit in the

Jan 1, 1932

By R J. Holmes

An accurate knowledge of the chemical, mineralogical and physical characteristics of ores and mineral products that are mined, processed and traded is crucial to effective resource utilisation, plant design, process optimisation and finally quality control to ensure that contract specifications are met. However, all too often the responsibility for sampling is entrusted to managers and personnel who do not fully appreciate the significance and importance of collecting representative samples for analysis, and everyone seems satisfied as long as some material is collected and returned to the laboratory for analysis. Furthermore, sample stations incorporated into the design of new plants are often the first casualties when cost cutting exercises commence. This needs to change, because there is little point in accurately analysing samples if they are not representative in the first place. The resultant analyses can be next to meaningless and the effort taken to analyse such samples is to a large extent a waste of time and resources.Ultimately, a poor knowledge of the characteristics of ores and mineral products limits the ability of mining companies to optimise the life of ore resources and plant performance, and failure to meet final product specifications can have disastrous consequences, including price penalties and more seriously loss of sales contracts. It is high time that sampling is given the attention it deserves as the first critical step in the quality measurement chain.CITATION:Holmes, R J, 2013. The importance of sampling in the mineral industry, in Proceedings MetPlant 2013 , pp 34-49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By W. E. Stephens, A. J. Boyce, D. Lowry

Paper presented at Mineralisation in the Caledonides, the Mike Gallagher memorial meeting held in Edinburgh, 27-28 June 1996. An integration of S isotopic, fluid and mineralogical data for granitoid-related mineralisation showed that the porphyry systems had a predominantly subcrustal magma source, but the inner magma pulse of two-mica granite in the Fleet pluton was derived mainly from reduced sediments. The porphyry-style mineralisation formed from boiling fluids at high crustal levels, with a moderately saline fluid percolating down to the upper veins as they cooled but not penetrating the deeper Talnotry deposit. Veins in peripheral greywackes have a significant magmatic component but also incorporated CO2-rich components and metals released by dewatering of host sediments in response to granitoid intrusion. The low grade of regional metamorphism resulted in the significant fluid input from country rocks which led to the more exotic mineral compositions, especially where argillaceous sediments were involved

Jun 19, 1905

By J. K. Richmond

This is a progress report summarizing more than 5 years of a long-range Bureau of Mines research program. The purpose of this program has been to investigate the fire and explosion properties of Green River oil shale in the Bureau's Experimental Mine, in laboratories, and in the field. The lean limits of explosibility of oil shale dust, by small-and large-scale tests, are reported as a function of grade, ignition source, and particle size. A limited number of laboratory tests on the autoignition of oil shale dust layers and the spontaneous combustion tendencies of oil shale are described. Moderate-scale rubble fire tests were conducted to determine flame spread rates as a function of ventilation flow. With the aid of a system to continuously monitor methane emissions in a deep oil shale mine, the characteristics of the methane flow are reported as a function of ventilation and blasting procedures, and are compared with gas yields from core samples. Tentative predictions as to the emission of the methane to be expected in deep oil shale mines, far from the outcrop, are offered. Brief reference is made to a parallel investigation into the fire and explosion hazards of oil shale mining and processing by a Bureau contractor; detailed results of the latter investigation are to be found in the contractor's reports.

Jan 1, 1982

Bahrain's oil revenue increased from $337 million2 in 1916 to $378 million in 1977. Despite the increase in value, petroleum receipts made up only 584 of all Government income in 1877, compared with 74% in 1976 and 83% in 1975. Bahrain became an oil producer in 1932 with the discovery of the Awali oilfield, and since that time, the Awali oilfield has produced over 600 million barrels of crude oil. Awali production in 1977 was 21.2 million barrels. Bahrain shares the revenue from the Abu Safah oilfield, located in the Persian Gulf north of Bahrain, equally with Saudi Arabia. Revenue from the Abu Safah oilfield was approximately $179 million or 47% of oil revenues in 1977. Output from the Abu Safah oilfield was 48 million barrels, an increase of nearly 30% over 1976 output. The Bahrain Petroleum Company (BAPCO). the nation's only oil-producing company, was owned 40% by California Texas Oil Corp. (CALTEX and 60% by the Govern¬ment. The Government established Bahrain National Oil Co. (BANOCO) in 1976 to administer the Government's share of BAPCO, oversee exploration concessions, and manage domestic marketing of petroleum products. The Government announced its intention to acquire 100% control of crude oil and natural gas production. CALTEX was to retain complete control of the 250,000-barrel-per-day oil refinery near Sitrah.

Jan 1, 1981

By Richard Mcivor, Largo Albert

"Inco Limited has operated aluminum mine shaft conveyances since 1968. Aluminum conveyances are used where the hoisting in system requires lightweight conveyances to maintain the hoist rope safety factors and mine hoist rope pulls as dictated by government regulations. Inco Ltd. currently has 20 skips (including spares) operating in the Ontario Division mines. The main problems encountered are with galvanic corrosion between dissimilar metals and metal fatigue. This paper will highlight some of the problems encountered and illustrate methods utilized to overcome the problems and improve the conveyances performance.IntroductionAluminum mine shaft conveyances have been in use at Inco Limited's various Sudbury district mines since 1968. All of the conveyances currently in use are skips used for hoisting mine ore and rock. Inco had an aluminum quick change Kimberley-type skip and cage in operation at its Totten Mine in the early 1970s, but this mine is no longer in operation and no further comment will be made.The primary reason why aluminum conveyances are chosen over conventional steel conveyances is because of their light weight. Typically an aluminum conveyance will weigh about 60% to 70% of a steel conveyance of similar design. The lighter weight conveyances will allow higher payloads to be used and still maintain the statutory hoist rope factors of safety. It must be remembered that increasing the payload will increase the power required to raise the load and the hoist will have to have the necessary horsepower for the increased payload or the system will be overloaded.The front dump (Rola-chute) skips are of the bail-less design, i.e. the box structure also supports the load and has the shaft guide shoes attached directly to the side of the box structure. The Copper Cliff North Mine and South Mine skips have a joint in the centre of the conveyance and are installed in the shaft in two sections and connected with pins. This feature allows very long (42 ft) skips to be used in areas where a one-piece bail-type conveyance could not be installed. It is not practical to make sectionalized bail-type conveyances"

Jan 1, 1988

By K. Wongaew, R. F. Cook, J. E. Carlson, T. Cleys, C. R. Smith

Steel fiber reinforced concrete segmental rings are the final tunnel lining for approximately 85% of the alignment for a 6.706-meter (22-foot) internal diameter tunnel being built as part of the East Side Combined Sewer Overflow Tunnel Project. This paper describes the approach adopted for the design of the steel fiber reinforced concrete segments, the development of the performance criteria for the segments, and the testing program used to confirm the performance of the materials and segments in the laboratory and in the field.

Jan 1, 2007

By Jorge Oviedo

La planta de lixiviación, extracción por solventes y electrodeposición (L-SX-EW) de Southern Perú es una operación hidrometalúrgica dedicada a la lixiviación ácido – bacteriana de los botaderos de mineral de baja ley de la Mina Toquepala, para la producción de cobre catódico de la más alta pureza. En ese sentido, el presente trabajo describe la evolución del sistema de control y supervisión de esta planta minera en Cuajone. Para ello, dicha planta debe tener una actualización constante de sus sistemas de control y ser capaz de cambiar con la velocidad a la que avanza la tecnología de Control de Procesos. Asimismo, debe contar con personal calificado que permita el desarrollo y modernización de los sistemas sea continuo y no dependa solo de expansiones y ampliaciones ejecutadas por especialistas externos. De forma que este software de supervisión, no solamente considera la capacidad de operar la planta, si no debe ser una ayuda tanto para el operador como para brindar información en la correcta toma de decisiones.

Aug 25, 2002

It is not uncommon to find large quantities of combustible materials in underground metal and non-metal mines. Support timber is the predominant combustible material. Spontaneous combustion, welding and cutting, shorted or overloaded electrical cables and careless smoking are common ignition sources. More recently, there is increased use of diesel mobile equipment that requires fuel storage and transfer areas. Diesel fuel spillage on hot engine manifolds and motors can result in rapid flame growth and heavy smoke accumulation in a matter of seconds. In-expensive, reliable fire detection and suppression systems are available to provide early warning of fire conditions and to isolate and extinguish fires that originate in fuel storage and transfer areas. This report presents an example of how technology developed and demonstrated under Bureau of Mines Contract H0242016, Mine Shaft Fire and Smoke Protection System, may be applied to protect underground diesel fuel storage and transfer areas. The area application described in this report is a representative example only; the fire protection described includes the concepts of ? Early warning and alarm ? Isolation ? Extinguishment ? Control

Jan 1, 2011

By F. J. Tavera, J. A. Finch

A probe suitable for on-line measurements of gas hold-up in industrial flotation systems has been developed. It is based on an open cell for measurement of slurry-gas conductivity and a novel syphon cell for measurement of slurry-only conductivity. The desired behaviour of the two cells was demonstrated and estimates of gas hold-up were shown to be in good agreement with independent measurements. The gas hold-up probe was used as a diagnostic tool to assess the operation of flotation columns. Differences in gas hold-up between baffled sections in two industrial columns were detected

Jun 18, 1905