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By T. S. Heah, S. T. Bishop

"The Lorraine property is located in the northern Intermontane Belt, north-central British Columbia. The property is underlain by intrusive rocks of the Duckling Creek Syenite Complex, an Early Jurassic, alkaline phase of the Late Triassic-Early Cretaceous Hogem Batholith. Two significant zones of copper-gold mineralization have been explored to date; the Main zone (historical Upper and Lower deposits) and the recently discovered Extension zone. A combined geological resource was estimated in 1975 for the Main zone deposits at 10 million tonnes averaging 0.7% Cu, and from 0.1 g/t Au to 0.34 g/t Au. The Extension zone, still at an exploration stage, is estimated to be considerably smaller than the Main zone.Copper-gold mineralization at Lorraine Mountain exhibits characteristics suggestive of both magmatic and hydrothermal origins, and may be related to orthomagmatic-hydrothermal fluid flow contemporaneous with magmatism and development of migmatitic fabrics. A depth greater than the depth of formation of classical porphyries may explain many of the variations displayed by mineralization at Lorraine. These characteristics distinguish Lorraine from other members of the alkalic suite of porphyry Cu-Au deposits in the Canadian Cordillera.IntroductionThe Lorraine prospect is located in the Omineca Mountains, at the headwaters of Duckling Creek, 56 km northwest of Germansen Landing (Fig. 1). The property is centred at latitude 55°55'N, longitude l25°26'W on NTS mapsheet 93N/14W. The area is typified by mountains of moderate relief, with elevations ranging from 1150 m in the valleys to peaks of 2000 m. Valleys are U-shaped and blanketed by glacial till which give way to steep, talus covered slopes and sharp ridges. Outcrop is generally limited to elevations above 1600 m (Fig. 2)."

Jan 1, 1995

By L. D. van Dyk, G. S. Tshofu

Iron ore fines are by-products of iron ore mining operations. Unlike iron ore lumps, fines cannot directly be used in conventional iron making processes, and consequently large quantities accumulate around the world. Pelletizing and sintering can be used to convert iron ore fines into agglomerates or briquettes for processing with lump ore, but these techniques are energy intensive and produce greenhouse gases. This research investigated the extraction of iron from iron ore fines using acetylacetone (a ß-diketone) as an environmentally friendly alternative process for fines utilization. A 2k factorial experiment design was used to identify the significant extraction variables. It was found that the reaction temperature and solid to liquid ratio had significant effects on the extraction process. The extraction kinetics were studied at different temperatures and the highest iron extraction (97 %) was obtained after 48 hours at 413 K and 0.025:1 (g:mL) solid to liquid ratio for a particle size range of +106 to -150 µm. The extraction products were easily separated from the unreacted acetylacetone by flash distillation and iron(III) acetylacetonate crystals were recovered. An economic evaluation showed that selling the crystals was profitable. Alternatively, the crystals can be reduced with hydrogen to iron particles and acetylacetone (for reuse).

Jan 1, 2015

By Henk Dijkman, Wageningen University, Paula Gonzalez Contreras, Irene Sánchez-Andrea, Jan Weijma, Silvia Vega

"More than 20 years ago, Paques B.V. introduced innovative biotechnologies to recover metals and to remove sulfate from aqueous streams. These technologies find their origin in the exploration of microorganisms involved in the global sulfur cycle. Currently, several sulfur cycle biotechnologies are applied successfully at full-scale. The sulfur cycle is closely linked with the iron cycle, and also the latter offers opportunities for application of innovative biotechnology for the mining industry. Microorganisms of the natural iron cycle carry out reactions that are not feasible by chemical methods such as ferrous iron oxidation with oxygen at pH below 4. Iron oxidation with oxygen can be conducted using microorganisms living at pH between 0.5 and 7 and at temperatures between 0 and 95ºC. Remarkably these microorganisms can also carry out arsenite oxidation at similar acidic conditions and high temperatures. Making use of the extreme features of these microorganisms, Paques and Wageningen University have developed a biological process to precipitate arsenic as scorodite. This biological formation of scorodite is a novel combination of biological oxidation and biocrystallization. Depending on the level of saturation, biological oxidation rates and operational conditions, we could control the formation of the iron precipitates such as jarosite and scorodite. Currently new microorganisms have been harvested from hot springs and rock acid mine drainage to foster the growth of specialized microbial communities with potential high iron and arsenic oxidation capacities and higher resistance to other metals. In our paper we address the ongoing research and development of the bioscorodite process.THE USE OF IRON TO REMOVE ARSENIC In 2015 several environmental disasters related to the release of mine wastewater and tailings occurred. On August 5th, a waste water spill occurred from the Gold King Mine near Silverton, Colorado. A dam holding the tailing pond was damaged and spilled three million US gallons (11 ML) of mine wastewater and tailings, including elements such as cadmium, lead and arsenic, into Cement Creek, a tributary of the Animas River in Colorado. “At their peak, arsenic levels were 300 times the normal level and lead was 3,500 times the normal level” (The Guardian, 2015). In early November, another collapse of a mining dam in the Brazilian state of Minas Gerais spilled between ten and sixteen thousand US gallons of water and sediment after a dam failed from an iron ore mine. Arsenic and mercury polluted the Doce River, arsenic levels were found more than ten times above the legal limit in some places of the river (The Guardian, 2015). Waste production is inevitable during Mining. However, a preventive waste management strategy could have minimised waste production, maximised waste reuse and classified waste by their hazardous degree."

Jan 1, 2016

By Jon Errey, Aleksandar Petrovic, Karl Haase

"Developing a gold deposit of this magnitude in the Amazonian jungle of Guyana posed many challenges. This paper describes not only the process & logistical challenges arising from the remote mine site location in a tropical environment with a local industry unaccustomed to recent large scale gold mining operations, but also the innovative technical solutions employed to address the unique ore body characteristics. The best examples of this approach were dealing with the initial high clay content saprolite ore from the development phase and primary mining pits whilst ensuring that the design also implemented the right method to deal with the future fresh rock in an environmentally sensitive habitat. In order to do this separate individual crushing flowsheets were generated, focusing on the specific material handling equipment that would be suitable to handle these various types of material and ensure high recoveries were maintained.INTRODUCTIONAurora gold mine is located in forested region of Guyana, 170 km west of capital Georgetown, and 130 km West North-West of Bartica, a settlement at the junction of the Essequibo and Cuyuni Rivers.The Aurora gold project (Aurora) is a 5,000 tonne per day open-pit/underground operation, which will produce a total of 3.29 million oz. gold – averaging 194,000 oz. per year – over an initial 17 year mine life. At the final investment decision in 2014 Aurora had a total resource of 6.54 million ounces in the measured and indicated categories (62.83 million tonnes at 3.24 g/t Au) as well as additional 1.82 million ounces in the inferred category (16.93 million tonnes at 3.34 g/t Au)."

Jan 1, 2016

By Alain Simard, André Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1990

By Alain Simard, Andre Gobeil, Sylvain Lacroix, Maurice Rive, Denis Racicot, Pierre Verpaelst

"The Abitibi volcano-plutonic belt forms the major portion of the Abitibi lithotectonic subprovince in the Superior Province. The Abitibi belt is composed essentially of"" (1) approximately 2.7 Ga old volcanic and sedimentary rocks; and (2) gabbro, tonalite, granodiorite and syenite intrusions occurring in well-defined prekinematic ( synvolcanic ), synkinematic and post-kinematic plutonic suites. Most of these rocks are metamorphosed to greenschist facies. Regional multi-phase deformation affects the volcano-sedimentary rocks. Deformation was initiated as these rocks were formed, and peaked at the end of the Keno ran orogeny with the emplacement of granitic batholiths.There are 145 former and current mines in the Quebec segment of the belt. To date, more than 420 Mt of ore have been extracted yielding 1,600 tonnesof Au, more than4,000 tonnesof Ag,4,400,000 tonnes of Cu and 5,300,000 tonnes of Zn. Mineral production is concentrated in geologic domains that approximately coincide with the boundaries of lithotectonic domains. We have compared the geology and mineral deposits of different domains to illustrate their distinct metallogenic signature. Certain domains are dominantly gold-producing (Cadillac-Malartic, Val-d'Or, Caopatina), others are base-metal producers (Matagami and Normetal), while others produce both gold and base metals ( Rouyn-Noranda, Chibougamau, Casa-Berardi-Joutel).Gold is extracted from quartz-rich vein deposits (for example, Val-d' Or), sulfide-rich veindeposits(Cadillac or Chibougamau) and from volcanogenic massive sulfide deposits ( Rouyn-Noranda). Base metals are generally mined from volcanogenic massive sulfide( RouynNoranda, Matagami, Normetal), although certain vein deposits yield base metals (Chibougamau) . Certain sectors are dominantly zincrich (Matagami, Normetal)."

Jan 1, 1989

By A. P. Yovanovic, P. Bonadia, M. N. Moraes, C. F. Matos

"The magnesite flotation operation of Magnesita Refractories, in Brumado – Brazil, has four parallel ball mills working in closed circuit with hydrocyclones to grind the ore for the reverse flotation of silicates in mechanical cells. The modification proposed here opens the circuit for three of the ball mills so that their products are collected together to feed a high frequency screen. The oversize of the screen feeds the fourth ball mill in closed circuit for secondary comminution. The product reports to dewatering and flotation. The undersize undergoes desliming and subsequent flotation operation. According to pilot tests performed, the modification on the magnesite flotation operation will promote a 20% increase in the productivity, 8.5% increase in mass recovery and a 26% reduction in water consumption. The gains are due to the fact that the silicates in the feed are concentrated in the smaller particles (<100µm) with over grinding in the existing closed comminution circuit, making it impossible to take advantage of this natural selectivity. The combination of open circuit, more selective milling, and the high frequency screen, ensures high efficiency particle size classification. This renders the process more effective, both to the screen undersize with its high contents of silicates and fines, and to the screen oversize, which is almost without fines and has a higher magnesite grade. This situation allows for the setting of specific parameters for the flotation of both the primary milling undersize and the secondary milling product.INTRODUCTIONMagnesita Refractories, with its operations site in Brumado, is the largest producer of high purity dead burned magnesia (DBM) in Latin America. The magnesite ore is extracted from an open pit mine, named Pomba, after which it is crushed and handpicked. Due to the presence of disseminated silicate the ore has to be ground and concentrated by means of reverse flotation, before feeding the high temperature kilns for sintering and conversion to DBM.The magnesite flotation unit has an impact crusher to reduce the size of the feeding ore, which is transported to the mills by conveyor belts. The milling operation is composed of four ball mills in closed circuit with hydrocyclones. The closed circuit generates a high circulating load with excess fines, which is detrimental to the selectivity of the desliming and flotation operations, reducing both mass andmetallurgical recovery.In the current scenario, the capacity of the flotation plant is insufficient to meet the demand of the DBM kilns, forcing the operation to work with high purity ores in order to attain the highest possible mass recovery in the concentration process. This is not an ideal situation as it requires the mining site to work with higher stripping ratios.The objective of this work was to improve the magnesite flotation unity to increase its productivity. After a detailed analysis, the milling was identified as the limiting process, which made the authors to focus on this operation."

Jan 1, 2016

By Gary M. Poxleitner

Skip/Hoist ?Vertical Advantage of Hoist ?High capital ?High operating cost Trucks Trucks ?Flexibility of ramp ?Low capital ?High operating cost Conveyor Inclined High capital ?Low Cost to run ?Continuous Production ?High Capacity ?Transfer pointsMax Grade: +32%

Feb 1, 2008

By E. Herrera Alarcón, L. Mariscal Samaniego

The Teniente Converter (wet charge type) was commissioned in august 1995 and was designed to smelt 744 tpd (metric tons per day) of dry copper concentrates. Its products are white metal (73% Cu) that is sent to the Peirce Smith converters, slag that is cleaned in Reverberatory Furnaces and the process gases that are sent to the Sulfuric Acid Plant. Since its start up, the Teniente Converter smelting capacity was increased 1.6 times, from 800 tpd to 1,280 tpd using 33% oxygen-enriched air, and reaching an operative availability of 97%. By the other hand its campaigns have reached a record duration of 530 days without hot patching tuyeres and a partial refractory lining repair in the last four campaigns. This paper describes the most relevant improvements, as well as the strategies that had been used to reach these achievements.

Jan 1, 2007

By T. K. Bose

According to the Intergovernmental Panel on Climate Change (IPCC), the average global temperature has risen over the last century. If this trend continues over the next century, the IPCC projects a significant increase in temperature and a rise in sea level. The changes in climate could adversely impact human health, agriculture, water resources and ecosystems. Most national and international agencies have concluded that our use of carbon-rich fuel is responsible for global warming through the greenhouse effect. In the future, the situation may get worse if the increased need for energy in countries like China, India and Brazil is fulfilled by burning fossil fuel. Advanced natural gas-fuelled vehicles have the potential to reduce carbon monoxide and reactive hydrocarbon emissions substantially compared to gasoline vehicles. Further environmental benefits can be realized by using a blend of natural gas and hydrogen. Such an approach will help create an infrastructure for an eventual transition to hydrogen.

Jan 1, 2005

By M. J. Collins, B. Parekh, A. Hasenbank, B. Hewitt

Newcrest Mining Limited, originally as Lihir Gold, has operated a pressure oxidation plant for the recovery of gold from refractory ore since 1997. The mine and gold plant are located on Lihir Island in Papua New Guinea. Design of the original pressure oxidation circuit was based on the results of pilot plant tests conducted by Sherritt in Fort Saskatchewan. Following a decision to expand the plant in 2008, Lihir Gold contracted Sherritt to design a new autoclave. The design exercise utilized the original pilot plant test results, commercial process results at Lihir, and an understanding of advances in autoclave technology since the original plant was built. The new Lihir autoclave will be the largest horizontal, multiple-compartment autoclave in the world. The design process for the pressure oxidation expansion is described in this paper.

Jan 1, 2011

By H. Memarian

In the last few decades, many developing countries have tried to expand and improve upon higher education, which is acknowledged to be the leading factor for development. In this respect, develiping countries have significantly increased the number of tertiary institutions and their students. These rapid expansions, along with all the benefits, have drawbacks as well. An example is the status of mining engineering education in Iran. Presently, the number of active mining engineering departments in Iran (27) is more than the sum of similar departments in Canada, Australia, the United Kingdom, and South Africa (23 altogether). Also, the number of annual mining graduates in Iran (645) is more than the cumulative graduates of the United States, Canada, the United Kingdom, and Australia (613). The expansion of mining engineering education in Iran has coincided with the closing or merging of similar mining departments, as well as a decline in the number of interested students in the industrialized world. The present study shows that the need for development and the excessive number of high school graduates, resulting from high population growth in the early 1980s, are the two primary factors influencing the significant expansion of mining engineering education in Iran.

Jan 1, 2007

By J. Seo

We propose a dynamic biomechanical simulation method that uses motion capture to evaluate the risk of Work-related Musculoskeletal Disorders (WMSDs). Statistics show that WMSDs accounted for 33% of all non-fatal occupational injuries and illness in construction in 2009, and were a leading cause of temporary and permanent disability. Present methods rely largely on self-reports from workers, observational techniques, and direct measurements of motion and muscle activity to assess awkward postures, physical loads, repetitiveness, and the duration of exposure. While these methods have helped to prevent WMSDs in construction work, they may not be suitable for estimating the internal tissue loads associated with WMSDs. We propose a dynamic biomechanical simulation method to estimate internal forces and moments at each body joint of construction workers with motion capture data. Particularly, we explore the biomechanical loads by simulating active 3D musculoskeletal models based on measured postures and movements. To demonstrate the feasibility of this approach, we studied a ladder climbing task using a portable ladder under controlled laboratory conditions. Postures and motions were determined with a commercial motion capture system (e.g., VICON). The results were analyzed to investigate the feasibility of identifying risk factors based on biomechanical simulation. The results show that the proposed approach allows us to determine the biomechanical basis for WMSDs, and to identify postures and movements associated with excessive physical demands on each body joint. When combined with marker-less motion capture which is our ongoing work, the proposed approach has the potential to assess an individual?s motions and to provide personalized feedback for the purpose of reducing biomechanical loads and WMSD risk in real workplaces.

Aug 1, 2013

By M. Lindgren, M. Latva-Kokko

Process performance can be significantly influenced by proper design of hydrometallurgical reactors. Optimal reactor configuration is case specific and depends on process requirements such as reaction rate limiting factor and particle size distribution. Choice of materials and manufacturing methods also play important roles in highly corrosive and abrasive environment often involved in hydrometallurgical industry. In this paper performance of different reactor designs has been compared in some typical hydrometallurgical applications. Results show that significant improvement in energy consumption, gas utilization efficiency and equipment lifetime can be achieved with process specific reactor design.

Jan 1, 2014

By C. A. Hardie, G. F. Leichtle, J. A. Finch, J. A. Watson

"The recycling of wastepaper has become an important and common process worldwide. Techniques similar to those used in the mineral processing industry are used to produce high quality recycled fibres for use in newsprint. The mineral processing group at McGill University, in conjunction with the Pulp and Paper industry (Mechanical and Chemi-mechanical Wood Pulp Network), has adapted one of these techniques, column flotation, for the purpose of deinking wastepaper. This article describes the typical process of recycling wastepaper from a mineral processing point of view. It also presents results from McGill University’s flotation column test work at a Québec wastepaper recycling facility. IntroductionThe recycling of wastepaper has become an important and common process worldwide, including Canada which is now the world’s largest importer of wastepaper (CPPA, 1996). Much of the current drive to increase the utilization rate of recovered paper is a reaction to the solid-waste disposal problem that faces many Canadian and United States municipalities. The real problem in the disposal of solid waste is not the absolute amount of garbage that must be disposed of each year, but this amount in relation to available disposal capacity.Environmental restrictions on the creation of new landfill sites and incinerators (the two main options for disposal of municipal solid waste) have tightened the demand/supply balance in the solid waste disposal market. This shrinking availability of waste disposal sites in the face of increasing population with greater disposal requirements defines the Developed World’s solid waste crisis. Not only are there fewer disposal sites available, but the costs of using them is skyrocketing. These factors have increased government regulations mandating recycled paper content in newsprint. Conservation and environmental issues make the current drive for wastepaper recycling a real issue and business opportunity."

Jan 1, 1999

By Luke Evans

What are Best Practices? What are Bad Practices? Who Uses Best Practices? Why Bother? Acceptability Guidelines Published Best Practices Published Bad Practices Additional Best Practices Some Best Practices for Low Grade Deposits Interpretation Guidelines Big Bear Gold Deposit Example Conclusions Questions

May 1, 2013

By A. Lloyd, Montgomery, J. Jorgesen, W. J.

"Coals are ranked according to their degree of metamorphism or progressive change in the natural series from lignite to anthracite. The reader is referred to ASTM Standard D-388, ""Standard Classification of Coals by Rank"" for a detailed description of the system in use throughout North America including Canada.Fixed carbon and calorific value (expressed in Btu/ lb) calculated to the mineral-matter-free basis have been chosen as the main characteristics from which rank is established. Higher rank coals are classified according to fixed carbon content, lower rank coals according to the calorific value on a ""moist"" mineral-matter-free basis. Certain adjacent groups are differentiated according to their agglomerating (caking) properties. ""Moist"" refers to inherent moisture. Referring to Table 1, coals having calorific values greater than 14,000 Btu/lb on a moist mineral-matter-free basis and fixed carbon of 69% or more on a dry mineral-matter-free basis are classified according to fixed carbon. Coals having calorific values of less than 14,000 Btu/lb on a moist mineralmatter-free basis are classified according to calorific value on a moist mineral-matter-free basis. Agglomerating coals having 69 to 86% fixed carbon on the dry mineral-matter-free basis are classified in the low or medium volatile group of the bituminous class according to their volatile matter content. Agglomerating coals having calorific values between 10,500 and 11,500 Btu/lb are classified in the high volatile C bituminous coal group; nonagglomerating coals in the same calorific value range are classified in the sub-bituminous A coal group."

Jan 1, 1985

By Stephen van Duin

As productivity in coal extraction demands increase in underground coal mines, the industry is faced with finding new ways to support production without jeopardising safety. In modern mines the capacity and scale of longwall coal extraction has steadily increased to a point that support processes are failing to keep pace. In particular, roadway development is continually placed on the critical path of activities which maintain mine production, so any inefficiency in this area is quickly exposed. Original equipment manufacturers are under immense pressure to modify their machines to be more interconnected with each other, with machine communication and logistical sharing of space becoming a known requirement. This paper looks at the changing trends in mining practice, analysing available technology as well as currently emerging research into hard automation and discusses the need to integrate machinery and processes in order to see increases in productivity and safety.

Aug 1, 2013

By K. M. Mayhew, G. D. Barr, T. M. McCoy, C. T. Knilans

"Teck Resources Limited (“Teck”) has developed and extensively tested on a continuous basis the CESL Technology hydrometallurgical process for treating copper and nickel sulphide concentrates, including bulk copper-nickel concentrates. Copper, nickel and cobalt are leached efficiently into solution, utilizing CESL process conditions. Total precious metals including gold, silver, platinum and palladium are recovered from the residue stream via sulphur flotation. This paper describes the CESL Technology testwork on a bulk copper-nickel concentrate derived from Twin Metals Minnesota?s (TMM) deposits within the Duluth complex and evaluates the economic benefits (increased cash flow, increased revenue certainty) and investment criteria (capital cost, payback and cash flow) of incorporating CESL Technology into the staged development of TMM?s deposits.INTRODUCTION Mineral Processing and the Role of Hydromet in the Duluth Complex The Duluth Complex in northern Minnesota, United States (US), represents one of the largest undeveloped accumulations of copper, nickel, gold, and platinum group metals (PGMs) in the world, ranking second in copper and PMs and third in accumulation of nickel. The figure below identifies some of the larger known deposits within the Complex (see Figure 1). Copper, nickel, PM and PGM mineralization within the Duluth Complex is hosted by mafic to ultramafic intrusive rocks that are part of the overall intrusive complex.One of the mineral processing challenges of Cu-Ni-PM-PGM deposits in this Complex is the complicated, polymetallic nature of the mineralization1: copper occurs primarily as chalcopyrite and cubanite with minor occurrence of talnakhite; nickel occurs as pentlandite and refractory nickel oxide/silicates; iron sulphides are present as both pyrrhotite and troilite; and PMs/PGMs occur in both the sulphide matrix as well as discrete minerals. An additional challenge for the Duluth Complex is the ratio between copper and nickel; in most of the identified deposits, copper grade is three to four times greater than the nickel grade, which precludes the production of a simple bulk concentrate due to the lack of a traditional smelting market for a bulk concentrate of this character."

Jan 1, 2017

By P. R. Cook

Thunder Bay Terminals&apos; plant, now in operation, cost about 70 million dollars and was completed on time and under budget. The paper is the project manager&apos;s account of this accomplishment. From site selection through feasibility, engineering and construction to realization, he emphasizes the necessary philosophies for the control of time and money. The computer as a tool is discussed, as well as techniques for procurement.

Jan 1, 1979