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By Dina M. Aloi

In today?s evolving and globalized world, mining companies are being pressured to move beyond compliance towards long-term sustainability and sustainable development. Companies are expected to ?engage? communities without a clear understanding of ?how? to do this or to what end. This move, away from compliance, develops more of a focus on ?Community? Social Responsibility and sustainability. This shift leads to the development of world-class projects that provide sustainable development for people, reduce the incidence of costly delays, and promote good global citizenship for companies. The process of ?engaging? communities in mining project design and development leads to a stronger license to operate, and a reduction in social and political risk. To create this mutually beneficial relationship between communities and companies, communities must be ?engaged? in the project development and risk assessment processes as early as possible, preferably during the exploration or the concept phases. How to create this ?engagement? and manage this risk will be discussed.

May 1, 2007

By Daan Maijer, Wade Marquardt, Robert MacKay, Steven Cockcroft, Farzaneh Farhang Mehr

"To comply with the new Corporate Average Fuel Economy (CAFE) standards, the automotive industry is aiming to reduce weight and increase the power and efficiency of small displacement engines through the application of forced induction technologies. As an example, there are now several 2.0 litre turbocharged engines in production, producing in excess of 240 hp. To meet the need for improved fatigue properties in the engine blocks used in these high-output engines, a new water-cooled chill technology is under exploration at UBC in partnership with General Motors and Nemak. A series of experimental techniques were used to assess the capability of the new chill to extract heat from an A319 casting in the vicinity of the main bearing bulk head. The results show that this method has the potential to achieve a reduction in secondary dendrite arm spacing thus meeting the new microstructural specifications for these engines.INTRODUCTION The automotive industry is working to meet the stricter efficiency requirements laid out within the CAFE (Corporate Average Fuel Economy) regulations (Bastani, 2012; Cole, 1995; Mackay, 2011; Miller, 2000), while at the same time not sacrificing performance. One approach is to increase the use of lightweight materials, which leads to a decrease in the overall vehicle weight and fuel consumption (Cole, 1995; Mackay, 2011; Miller, 2000). Other approaches include smaller displacement engines and gas-electric hybrid drivetrains. However, one trend that is becoming clear, is a greater emphasis on force induction gasoline engines. This allows for weight reduction to be achieved with smaller displacement engines without sacrificing performance. One consequence of this approach is that the engine block materials are subject to higher in-service thermal and mechanical cyclic loads (Cole, 1995; Miller, 2011; Heysler, 2001) The fatigue properties of an alloy are strongly affected by a number of the, as-cast, microstructure features including, Secondary Dendrite Arm Spacing (SDAS), porosity and eutectic lamella spacing (including intermetallic ß-Al5FeSi platelets) (Mackay, 2010a; Mackay, 2010b; Viet-Duc, 2015; Casellas, 2005). It is generally accepted they can act as fatigue initiation sites and that a reduction in their size will result in an improvement in fatigue performance. For a given alloy chemistry, one of the key parameters affecting the length scale of all three is cooling rate (Mackay, 2000)."

Jan 1, 2017

By Robert E. McIvor

"The Functional Performance Equation for ball milling circuits allows us to isolate the circuit classification system efficiency (CSE) from the mill’s grinding performance. The factors which affect circuit CSE are reviewed, with emphasis on water usage at the classifiers. It is shown that manipulation of such water usage can be carried out to improve plant grinding circuit efficiency, at times by more than 30 percent.THE FUNCTIONAL PERFORMANCE EQUATIONObservation of the feed and product size distributions going into and discharging from the mill in grinding circuits with low versus high circulating load ratios initially led to the definition of “circuit classification system efficiency” (or CSE, McIvor, 1988a), and ultimately the discovery of the Functional Performance Equation (McIvor, 1988b, and McIvor et al, 1992). The CSE is the percentage of “coarse” (typically with reference to the plus P80) size material occupying the mill (versus “fines” or product size material, finer than the circuit P80), and can be calculated by taking the average of the percentage of coarse material in the mill feed and mill discharge. As this also represents the percentage of the mill energy expended on targeted, coarse size material, it is directly proportional to overall grinding circuit efficiency and production rate. This is all clearly expressed in the Functional Performance Equation for ball milling circuits, which is derived as follows.We define “fines” as any product size material, and “coarse” as that targeted to be further ground, the two typically differentiated by the circuit target P80. For any grinding circuit, the production rate of new, product size material (fines) must equal the specific grinding rate of the coarse material (i.e. fine product generated per unit of energy applied to the coarse material) times the power applied to the coarse material."

Jan 1, 2009

By N. Hosking, M. Nichols

Aluminum alloys are increasingly used for automotive body construction but are susceptible to filiform corrosion or paint blistering in service. Filiform corrosion resistance of two 6000-series aluminum alloys was investigated in this work. Test panels were produced with full automotive coating layers and scribed parallel and perpendicular to the rolling direction. The corrosion exposure comprised an inoculation step with acidified salt solution followed by a 6-week exposure period at 95% relative humidity and either 25°C or 70°C. Greatest corrosion activity was measured on the alloy with higher copper content, AA6111. Higher temperature exposure led to greatly enhanced corrosion activity for AA6111 compared to the lower temperature exposure. The 70°C exposure also led to greater mean corrosion-affected area measurements for the low copper aluminum alloy, AA6022, but the effect was not as stark as that observed for AA6111. Rolling direction affected the propagation direction, and possibly mechanism, of the corrosion effects. Cross-sectional analysis revealed dense corrosion products within the filament, comprising mostly aluminum and oxygen but with traces of chloride and sulphate. Development of varying filament and blister types on a single test panel and the progression of corrosion underneath a filament into the substrate indicate that several corrosion mechanisms can develop on the test panel, testament to the complexity of the corroding surface developed on an aluminum automotive body panel.

Jan 1, 2015

By Arnaud Faucher, Claude Bazin, Marilène Renaud, Mohamed Mai Manga

"Grinding circuits are operated in the presence of disturbances due to ore changes and equipment malfunctions. One of the challenges faced by the operators is the detection of a disturbance, the identification of its origin and of the action needed to minimize its impact on the process. Hydrocyclones overloading, worn or partly plugged apexes of the units of a nest, surging and internal liner detachment may cause a loss of classification capacity and quality. Recovery losses in downstream leaching or flotation circuits justify the effort in developing techniques for the detection of hydrocyclone malfunction. Two approaches for the detection of hydrocyclone fault are presented in this paper. The first proposed method uses the conventional sensors available in a grinding circuit allowing real time detection of hydrocyclone abnormal operation. The second technique is based on the use of vibration sensors installed on the hydrocyclone of a nest. This last technique enables the classification of the hydrocyclone malfunction as surging, overloading and plugged apex. The two techniques can be combined to increase the robustness of the problem detection.INTRODUCTIONHydrocyclones are used for many purposes ranging from water separation, fines removal and obviously for the preparation of the feed for subsequent concentration circuits in a mineral processing plant. The strategic role of the hydrocyclones for the preparation of the feed to the concentration circuit is often underestimated because of their simplicity of operation and robustness (Napier-Munn et al., 1996; McIvor, 1988). It remains that despite their simplicity, hydrocyclones have been studied extensively from 1970 to 1990 with the objective of developing mathematical models of their operation to be incorporated into grinding circuit simulators (Napier-Munn et al., 1996; Lynch, 1977; Flintoff et al., 1987). Such a development effort is already an acknowledgement of the importance of these units in a mineral processing plant. Several authors (Del Villar et al., 1996; Plitt and Kawatra, 1979; Casali et al., 1998) proposed soft sensors to estimate the classification efficiency of hydrocyclones using sensor measurements. However, few of the proposed sensors are used in the industry. More recently several papers were published to discuss the application of 3-D modelling of the hydrocyclones (Narasimha et al., 2005; Cullivan et al., 2004) and sensors (Bond et al., 1999; Neesse et al., 2003; Hou et al., 1998; Olson and Waterman, 2004; Williams et al., 1995; Willams et al., 1997) to help in the detection of hydrocyclone malfunction."

Jan 1, 2010

By Rajiv Kalra, Ji Jiangang

"This paper reviews the following aspects of the world’s largest manufactured Grinding Mill’s in terms of diameter and power, along with the world’s biggest shop assembly and trial run of the mills delivered to Sino Iron Magnetite Project in Australia.1. An overview of the basic flow sheet of the Sino Iron (Magnetite) Project located in Australia2. An overview of in-house designed CITIC Heavy Industries 12.2 m (40ft) F x 11 m(36ft) LG – 28MW AG mills including FEA and major components3. In-house manufacturing at CITIC-HIC work in Luoyang China of all major components for 6 off Ø12.2 m(40ft) AG mills and 6 off Ø7.9 m(26ft) x 13.6 m(44.6ft) LG – 2 x 7.8 MW Ball Mills4. Major aspects of design and preparation of the biggest shop trial run of Ø7.9 m(26ft) x 13.6 m(44.6ft) LG Ball Mill witnessed by international EPCM’s and clients in July 2009.5. Major aspects of one piece assembly of 1300 tonne rotating element of the Ø12.2 m(40ft) x 11 m(36ft) LG AG Mill and Ø7.9 m F (26) x 13.6 m(44.6ft) LG Ball Mill at the port of the export China and transport to Australian Port and then to site.6. An insight to unique installation methods used for Ø12.2 m(40ft) and Ø7.9 m(26ft) rotating element lifting on the mill foundation in one piece assemblies.7. CITIC Heavy Industries present capability for in house design and manufacture of Grinding Mills up to Ø13.7 m (45 ft) with 35 MW Gearless drives and Ø12.2 m(40ft) with 2 x 10 MW Geared Mill drives"

Jan 1, 2012

Many mines in Canada, the US and S. Africa are reaching the hoisting limit. Very little payload will be possible without compromising safety due the excessive weight. It has been suggested (DeLorme, 2000), that one of the most attractive concepts to enable deeper hoisting is to reduce the allowable factor of safety in the wire rope. Researchers at the Spokane Research Lab are developing new technology to improve hoisting safety and productivity by providing new monitoring and analytical tools. A Shaft Conveyance Monitoring System (SCMS) has been developed which determines hoist rope end load, true conveyance position and acceleration, and rope safety factor, as well as other hoist operating parameters. This information is transmitted to the hoist operator display 20 times per second. Recent field measurements on 45 mm(1 ¾ in.) diameter hoist rope indicate that dynamic forces during loading of a 9000 kg(10 ton) skip may exceed the safety factor of the rope. To improve on the current understanding of the mechanical behavior of hoist ropes, and to help interpret the results from field-testing of the SCMS, a new approach to computer modeling of stranded wire rope is also being developed. Particle Flow Code, PFC3D (Itasca 1995b) is used to simulate the structural behavior of wire rope and the interaction between individual strands when the rope is subjected to static and dynamic end loading. Details of the SCMS, field results from the measured rope loads, and the results of numerical modeling on the wire rope will be discussed.

May 1, 2002

By C. Taschereau, G. A. Vickell, A. R. Laplante

Evidence in support of an iron-gold corrosion cell during the high-temperature/highpressure elution of loaded carbon is presented herein including, but not limited to, its discovery, mode of genesis, and confirmatory laboratory testwork. A discussion of metallurgical and economic impacts, remedial investigations, plant design considerations, and future work including mitigative possibilities is presented.

Jan 1, 2006

By E. Zucker

In this paper, as in the 1960 CIM paper of the same name, s1gmf1cant new developments in electrical-mechanical mining equipment are briefly described. These include static thyristor-supplied D.C. drives for mine hoists, load-haul-dump systems, process controls with small and medium-size computers, and several other new items of equipment and Concepts. All the new hardware descriptions are given in the context of over-all process integration. This means the actual mechanical linking together of two or more processes and the preliminary step in the development of production-line mining.

Jan 1, 1969

The Shortage of Mining and Metallurgical Engineers I N many parts of the Western World attention has recently been drawn to the acute shortage of mining and metallurgical engineers produced by the universities. Naturally, the reasons for this shortage have been discussed, and various remedies for it have been proposed. In this paper, I want to examine some of them. It is now fairly generally ac-cepted among mining men that the easy attractions of modern urban life have left the career of mining in the metaphorical as well as in the literal backwoods. The industry finds it increasingly difficult to recruit adventurous and intelligent young men; for such men now seek their intellectual, if not physical, adventure in more glamorous occupations from a safe social base in suburbia. The salaries, opportunities and security offered by the mining industry do not complete effectively with the rewards offered by other industries and by commerce, taking into account the social disadvantages of a mining life. The excitement and other non-material attractions of mining

Jan 1, 1965

By F. J. Alcock

IN the summer of 1934, gold was discovered on Lodge bay, on the north shore of lake Athabaska in northern Saskatchewan, about fifty miles east of the Alberta boundary line. The first claims were taken up by the Consolidated Mining and Smelting Company of Canada, Limited, and there was a 'rush' to locate similar showings. Staking continued through the summer and succeeding winter, and in the spring of 1935 the provincial government established a recording office at a convenient point which is central to the more important holdings and where 'planes can land in any weather. During the past summer, the name of this townsite was changed from Beaverlodge to Goldfields, and a post office was established here. The season was one of great activity; a great deal of assessment and development work was carried out and a large amount of further prospecting done. In addition to the work by private companies, geological investigation was carried out in the region by a Federal Geological Survey party under the charge of the writer and a reconnaissance examination was made of an area of some 7,000 square miles surrounding the region of particular interest. Though this was the first discovery of gold in the region it was not the first occasion that prospecting had been carried out along the north side of lake Athabaska. Over twenty years ago, a number of prospectors were at work in the area and a large number of claims were staked, many of which were never recorded. One man by the name of Piché, in the years 1910, 1912, and 1913, took up a considerable number of claims north of Pine Channel narrows, east of Fond du Lac. His discoveries, which consisted of small showings of sulphides in sedimentary gneiss, proved to be of no economic importance. In 1915, a sudden widespread interest was aroused by the report that a sample of ore collected near Fond du Lac had yielded a very high assay in silver. In March and April of that year, prospectors began to rush into the field by dog teams to take up claims, and, as soon as the Athabaska river was free of ice, others started by boat from Athabaska Landing. Some hundreds of claims were staked and recorded in the Dominion Land Office at Edmonton or at Fort Smith. By July, most of the prospectors had? left the region, having failed to find any silver ore. In 1921, considerable prominence was given to the area a few miles east of Goldfields by reports that very large masses of iron ore were available there. Claims were taken up, but the material is much too low grade to be considered commercial ore.

Jan 1, 1936

By Raymond Philippe

Background ?Hatch Water has worked with most major mining companies in Chile on water supply and optimization projects ?Many(copper) mining projects are located in Northern Chile, which hosts the driest desert on earth Water supply options in Northern Chile ?River ?Availability/Rights ?Well(Brackish) Water ?Availability/Rights ?Municipal Wastewater ?Water rights ?Volume ?(Desalinated) Seawater ?Infinite source ?Cost depends on distance and altitude ?Recycling/Reutilization ?Water losses All these options present water quality issues

May 1, 2009

By R. R. Tatiya

"The ultimate aim of a mine design is to determine the development work involved and resources required by adopting one or more specific alternatives. A part of the process is the production of mining plans/designs, an outline of the amount of work and costs involved as well as a prediction of the revenues expected. The paper aims to examine these aspects of mine design using the computer models developed. These models are capable of designing and performing economic analysis for one or more stopes for a continuous orebody. IntroductionTatiya and Allen (1987) have described ’defining stope boundaries using a computer.’ Using the stope boundaries defined or even hypothetical ones, algorithms have been prepared to design the layouts of the following stoping methods: 1. sublevel stoping (longitudinal as well as transverse);2. DTH (Down-the-hole) stoping; and3. flat back cut and fill stoping with posts and pillars.Tatiya (1989) presented this work at the 21st symposium on the application of computers and operations research in the mineral industry (APCOM). Economic analysis of a stope is the additional feature incorporated with these algorithms.The system has been tested by an economic analysis of the three stoping methods modeled for a small portion of a deposit of a copper mining complex. The deposits at this mining complex form lenses of varying shapes and sizes, having low copper content. These chalcopyrite lenses are steeply inclined with a thickness in the range of 5 m to 60 m. The strata are competent and suitable for underground mining.In different sections of the mines different sets of equipment are used to perform the basic unit operations. Some of the ore handling levels in the mines are trackless, the rest are tracked."

Jan 1, 1998

By G. J. McTeer, D. L. Verhelst, D. J. Rioux

Teck Metals Ltd. operates an integrated zinc-lead complex at Trail, British Columbia, Canada. Since 1997, KIVCETTM flash smelting technology has been utilized for the treatment of zinc plant residues and lead concentrates. Trail Operations’ furnace uses four water-cooled jackets for bullion tapping. This paper provides an overview of KIVCET bullion tapping for the past 16 years, and discusses successes and challenges encountered with respect to operations, training and monitoring.

Jan 1, 2015

By S. Junnikkala, K. Föhr

"Experiments were performed with plant feeds with a continuous 1,8 m3 cell at Pyhasalmi mine with Cu flotation feed in order to test the applicability of the bubble surface area flux as an indicator of the flotation rate constant. It was found that bubble surface area flux could not predict the rate constants of coarse Cu containing fractions. In the middle size fraction, the correlation coefficient in the rate coefficient estimation was higher but not statistically significant. Only the fine fraction showed a linear relationship with a moderate correlation coefficient.The bubble surface area flux was shown not to be a function of the impeller velocity above a threshold value. The flux was an almost linear function of the superficial gas rate enabling to use the superficial gas rate instead of flux if the operation of an existing cell is to be estimated.INTRODUCTIONBubble area flux seems to offer a simple way of modeling flotation. It relates the flotation rate constant with the bubble surface area flux by a simple linear equation. Due to this, there has been a considerable interest in using the bubble area flux for flotation computations. It has even caused claims that a cell producing a high bubble surface area flux automatically produces a high rate constant and therefore a high recovery.This paper discusses some of the assumptions of the relationship and gives some plant results during two sampling campaigns.The bubble surface area flux s b is describing the area of bubbles available for flotation in a cell per unit area. The bubble surface area flux is related to the superficial gas rate J, by the Sauter mean diameter as follows"

Jan 1, 2001

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

By Lam. E. K., J. W. Jarvi, B. P. Bharadwaj

"The Rabbit Lake Operation is located in Northern Saskatchewan on the western shore of Wollaston Lake approximately 800 km north of Saskatoon, Saskatchewan.The Operation is owned by a joint venture of Cameco Corporation and Uranerz Exploration and Mining Limited. Cameco is the operator.The Mill started production in June 1975 under the ownership of Gulf Minerals Canada Limited and over the past twenty years has increased the rated production capacity to over twice the original design.The Mill was originally designed to process 485,000 tonnes per year of ore with an annual production of 2.0 million kg of U308 (yellowcake). During the past ten years changes in ore sources and process modifications have led to increased milling capacity and production targets. The Mill has treated a total of 8.6 million tonnes of ore and produced over 40 million kg of U308 in the twenty year period, despite the shutdown and cutbacks in operating time since 1989.The 1995 tonnage throughput was 206,000 tonnes per year. Annual production though has risen to 3.6 million kg of yellowcake despite the departure from full-time to half-time operation in 1991 (7 up-7 down). The forecast for the coming years will see tonnage rising from 300,000 to 570,000 tonnes, production of 4.5 to 5.4 million kg of yellowcake and an anticipated return in the year 1998 to full time operation.This paper will give a brief history of the Mill and focus on the present flowsheet and recent improvements to the process."

Jan 1, 1996

By Iina Vaajamo, Jani Jansson, Lauri Pesonen

In pyrometallurgical operations, structural integrity of a high temperature furnace plays a crucial role in the overall safety, profitability and ecological footprint of the plant. Furnace integrity is related to how reliable a furnace is and it can be compromised, for example, by having poor operating and maintenance practices, an inefficient cooling system and flaws in the overall furnace design. These flaws and poor practices might lead to unexpected shutdowns, production losses, increased emissions, or worse. This paper presents the main factors to consider when engineering a furnace and developing its operating practices, while ensuring safe and reliable operations without compromising process efficiency and quality of the final products. In this respect, Outotec’s solutions for the cooling system and for automation systems like PROSCON, Process Advisor, Sentinel and our Smelting Information Management System, are also introduced.

Jan 1, 2015

By Roger M. Jones

This paper comments on developments in bulk shipping which will be of direct interest to those who are considering the shipment of dry bulk minerals out of Nova Scotia by water. Various conveying systems, and the slurry system of loading, are considered, and the role of deep water ports as a catalyst to other industries is stressed.

Jan 1, 1971

By M. P. Amsden

"Ecstall Mining Limited, a subsidiary of Texas Gulf Incorporated operates the Kidd Creek Mine, a 10,000 tons per day base metal producer, near Timmins, Ontario. Two different ore types are mined and milled: copper-zinc and silver-lead-zinc. At the highly automated Ecstall Concentrator the ores are processed by selective flotation in threes individual circuits. One of the most important metallurgical tools for process control is a sample system incorporating continuous on-stream x-ray analysis. Recently this system was further automated by adding computer control of reagents for two copper-zinc flotation circuits. The computer programs, utilizing optimum seeking methods and smelter contract terms, have increased copper recovery 0.8%, zinc recovery 1.6%, and reduced reagent costs by 12%. Although not anticipated, copper and zinc concentrate grades were improved modestly as well.INTRODUCTIONSEcstall Mining Limited, a wholly owned subsidiary of the Texas Gulf Incorporated operates the Kidd Creek Mine, one of the world's major base metal producers, near the old gold mining centre of Timmins, Ontario. Discovered in 1964, the property was brought into production in November, 1966. Originally designed for 9,000 tons per day, the operation now treats 10,000 tons per day of two different ore types mined from a single open pit. In the near future, open pit ore will be supplemented by ore from an underground operation now being readied for productionAt the Ecstall Concentrator the ores are processed by selective flotation in three individual circuits. The whole plant is highly automated and control is coordinated from a central control room. The treatment process follows conventional practices although fine grinding is required for optimum flotation recoveries. Normally, two circuits treat copper-zinc ore at a combined rate of 6,500 tons per day while the third circuit treats 3,500 tons per day of silver-lead-zinc ore. Special production averages 2,400 tons per day."

Jan 1, 1973