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By Mark Richards

Highland Valley Copper is a large, open-pit copper mine in the southern interior of British Columbia. Reclamation has been in progress on the site since 1987. Some 6,300 hectares will have been disturbed at the end of the mine?s life, the majority of which will eventually be reclaimed. The establishment of vegetation and the development of a self-sustaining vegetative cover are the central components of the mine?s reclamation plan. The present vegetation-monitoring program for the reclaimed area represents a significant commitment of resources and only addresses a small portion of the site each year. In an effort to expand the area surveyed while improving the efficiency of the monitoring, the use of remote sensing is being investigated. Airborne multispectral imagery was acquired in the summer of 2001, and the results of the multispectral classification were compared to ground observations made during the routine 2000 and 2001 monitoring program. A thematic map with 17 vegetation classes was produced. Within the vegetation classes, there was a strong spectral separation between ? dry grasses? and ?legumes? with further separation according to their density. Green biomass could also be quantified remotely across a wide variety of vegetation types. During summer 2002, further aerial imagery was acquired in combination with a targeted ground-truthing program to determine characteristic vegetation types associated with recognized spectral signatures, which can be used in a supervised classification. It is anticipated that after some fine-tuning, it will be possible to shift the ground-sampling effort from areas where the aerial classification confidence is high to more complex areas.

May 1, 2003

By A. Yoshida, H. Miura, S. Yamaguchi, Y. Oyama

A discussion is given on the ionic equilibria and precipitation reactions in seawater based on thermodynamic analysis, in order to understand the solubility of nutrient salts from dephosphorization slag for marine phytoplankton. Solubility of constituent ions in aqueous solution in equilibrium with solid phases are determined using thermodynamic data. It is proposed that CO2 potential defined as log Pco2 should be considered as an additional parameter to the Eh- pH diagram for the ionic equilibrium of slag components in seawater, since magnesium and calcium carbonate precipitation reactions determine the solubility of ligand ions in nutrient salts, such as phosphates, silicate, and sulfate.

Jan 1, 2004

By G. Gagnon

"HistoryMining of the Schefferville iron deposits began in 1954 on completion of the 357 mile railway linking the mines and the St-Lawrence river port of Sept-Iles. Apart from crushing, no treatment of these ores was required before smelting. In the late 1950's, testwork began at schefferville to develop a process for upgrading the extensive lower grade deposits containing 51% iron with 15% silica (natural analysis). Engineering for a six million ton per year beneficiation plant using cationic silica flotation and the A-C grate kiln Began in 1970 and the first pellets were produced in mid-1973.Production requirements and operating difficulties have restricted capacity to approximately 85% of design but on going improvements are being made continuously to attain design capacity.GeologyThe sedimentary ore bodies of the labrador trough occur in a belt 5 to 10 miles wide and 60 miles long and contain 51 individual deposits varying in size from 1 and 60 million tons. The ores are classified into three main color groups."

Jan 1, 1981

By G. H. Hope, D. Green

"Recent process advances at Lac Minerals Est Malartic Division are discussed. The Est Malartic mill treats massive sulphide, copper/gold ore from the Bousquet 2 mine, to produce a gravity gold product, a copper flotation concentrate and a gold precipitate. The mill operation has been improved by the application of Knelson concentrators to replace jigs, the application of Outukumpu high grade tank cells and optimizing the cyanide leach to minimize cyanide consumption.IntroductionThe Est Malartic mill is located near the town of Malartic in the Abitibi Region of north western Quebec. The mill has been in production since the mid- J 930's processing mainly clean, free milling gold ore. Active mining from the Est Malartic mine ceased in 1980 and the mill was switched to custom processing of ore from La Mine Doyon located some 45 km to the west. This custom processing arrangement continued until 1987 when the expanded mill at Doyon became available to process all of the Doyon production. In 1987, Lac Minerals commenced development of a second mine at the Bousquet site located 40 km west of Malartic. This mine, Bousquet 2, is the down dip extension of the La Ronde mine developed by Agnico Eagle. During pre-feasibility evaluations, it was determined that modification of the Est Malartic mill to handle this new ore source was economically more attractive than building a new facility on site. Modifications to the mill to process the high copper/gold ore from the Bousquet 2 mine began in late 1989 and the new circuits were commissioned in mid-1990. Modifications included the addition of both gravity and flotation concentration circuits to recover coarse, free gold and the copper. The existing leach circuit continued operating on the copper flotation tailings with some minor modifications to the solution handling systems. An SO,/air cyanide destruction circuit was also added at this time."

Jan 1, 1993

By J. J. Taute, O. S. Tinkler, G. Zárate, K. C. Sole, J. Steeples

Global practice in copper solvent extraction is reviewed, based on individual plant operating data for 2018. The survey respondents account for almost 40% of global copper cathode production by solvent extraction and electrowinning. Regional trends in operating conditions, as related to the prevailing ore mineralogy, leaching processes, and life of mine are evaluated. The adoption and expansion of this technology in the African Copperbelt and Asia are assessed, together with the associated challenges of specific orebody characteristics. Trends in feed and electrolyte compositions and flow rates, and extractant and diluent selection, together with their impact on copper recovery are reviewed. The evolution of equipment design and associated ancillary processes are discussed, and new projects identified. INTRODUCTION Continuing from similar surveys carried out in 1997, 1999, 2003, 2007, and 2013 (Robinson, Davenport, & Jenkins, 1997; Jenkins, Davenport, Kennedy, & Robinson, 1999; Robinson, Sandoval, & Cook, 2003; Robinson, Moats, Davenport, Karcas, Demetrio, & Domic, 2007; Sole, Zarate, Steeples, Tinkler, & Robinson, 2013), global operating practice in copper solvent extraction (SX) in 2018 is reviewed. Contributing operations include established sites in the USA (8), Chile (9), Peru (2), Spain (1), Mexico (2), and Australia (2), as well as newer operations in Africa (7) and Asia (3). This survey represents 2018 copper cathode production of 1.91 Mt, or about 43% of world production by solvent extraction combined with electrowinning (SX–EW). Trends in operating conditions and performance, as well as equipment design and process technology choices are analysed. The significant expansion in production in the African Copper Belt is also discussed. There are currently about 130 operations worldwide producing some 4.6 Mt copper by SX–EW; of these, about half produced more than 10 000 t/a. Figure 1 shows global copper production by country. As it has for several decades, Chile remains dominant, with 36% of global production of cathode copper. Since 2005, the Democratic Republic of Congo (DRC) has increased production year on year, and now represents 23% of the global total (International Copper Study Group, 2017; Statistica, 2018). Copper production in Asia has grown significantly in the past decade, particularly since the ramp-up of Wanbao in Myanmar. There used to be numerous small copper SX plants in China (Schlesinger, King, Sole, & Davenport, 2011), although most of these have now shut down and Chinese production is lower than it was five years ago. The most important trend, however, is the rise of Chinese-owned mining companies, particularly in Central Africa, but also around the world more generally.

Jan 1, 2019

By T. L. Lee, D. Y. Tan, J. Mi

Considerable progress has been made in studying the mechanism and effectiveness of using ultrasound waves to manipulate alloy solidification microstructure, However, uncertainties remain in both the underlying physics of how microstructure evolve under ultrasonic waves, and the best technological approach to control the final microstructure and properties. We used the ultrafast synchrotron X-ray phase contrast imaging facility housed at the Advanced Photon Source, Argonne National Laboratory, USA to study in-situ the highly transient and dynamic interactions between the liquid metal and ultrasonic waves/bubbles. The dynamics of ultrasonic bubbles in liquid metal and their interactions with the solidifying phases were captured in-situ for the first time. The experiments were complemented by the simulations of the acoustic pressure field, the pulsing of the bubbles and the associated forces acting onto the solidifying phases, providing more quantitative understanding for using ultrasound to control the growth of dendritic grains and to enhance grain multiplication effects for grain refinement.

Jan 1, 2014

By K. Iturralde

The topic of this article is the automation and robotization in refurbishment processes of industrial buildings. The need to mold these production spaces is quite universal. Particularly in the regions with a high industrial development and with a lack of buildable land, there is a need to convert this kind of spaces into an improved production system. The latest developments can be a useful tool for achieving a more efficient way of reforming this type of construction. On the one hand we have the digital or computerized 3D Laser Scanning (Computer Aided Measurement) that allows an accurate 3D modeling of the entire building. On the other hand, the project management using BIM (Building Information Modeling) could provide an easy design of each of the elements of the refurbishment. Finally, through the production of construction elements using robotics as jig or for CNC (Computer Numerical Control) we achieve a neat production of each element. How can be all those technologies applied in the refurbishment or expansion of industrial buildings? The research takes a first approach and analyzes industrial buildings that can be called generic or not specialized. To narrow the field of refurbishment, three major factors are defined. The first is to minimize the bill of the energy consumption of the buildings. This could be done either insulating the envelope, reducing the waste-volume to be conditioned climatically or creating facilities for energy production. The second is that the refurbishment or expansion of industrial buildings should try not to interfere on the production process that takes place in the building. In other words, the assembly of the elements in the construction site should be quick and easy, causing the least of disturbance at the workplace. Finally, the research makes an approach towards a robot integrated industrial or productive building .

Aug 1, 2013

By R. Spring

"Soft-sensors are a computer software alternative to inadequate hardware instrumentation. Filters are averaging methods that reduce the noise in any sensor's signal. This paper introduces these topics and places them in a mineral processing context using then-product formula.Soft SensorsAs their name implies, ""soft-sensors"" are computer programs that estimate values for process variables (Tham, 1991). This approach is useful when the appropriate hardware sensor does not exist, is deficient, supplies only infrequent values, etc. For example, in mineral concentrators the traditional magnetic flowmeter/ nuclear density gauge instrumentation for measuring slurry flows costs $5,000 or more per flow and requires frequent maintenance. However, metal assays are commonly available from online X-ray fluorescence analyzers and application of the n-product formula (Taggart, 1945) to these assays conveniently provides software estimates of the flowrates (albeit only when the circuit is in steady-state).Soft-sensors are used by inferential controllers that base their control actions on the process values ""inferred"" by the soft-sensor. Such was the case at Brenda Mines where the rod mill feed tonnage controller used an inferred value of the cyclone overflow particle size (Bradburn, 1976). It was also the case at Brunswick Mining where reagent controllers adjusted reagent addition rates throughout the plant according to the various ore flowrates inferred by an expert system (Spring, 1991). A unique feature of the expert system soft-sensor was its dynamic flow models which compensated for residence times, material transport lags, etc. Thus the soft-sensor values were valid under both steady-state and nonsteady- state conditions."

Jan 1, 1992

By M. Hosseinzadeh

By changing the quality of consumed refractory bricks in burner zone of sarcheshmeh copper complex anod kiln removing of carbon precipitation phenomenon was studied. For blister deoxygenation LPG is blowing in anod kiln and cause destoring microsturcture and bonding of refractory bricks. Studies are shown that in a part of the bricks which have a temperature of 800 - 1000 °C , iron content phases in magesia - chromite bricks are like catalist and cause increasing the rate of carbon precipitation reactions . In a way that in comparsion of two bricks with best and medium quality with different analysis, this problem is more critical in best quality bricks containing high iron oxide. Therefore special magesia spinel bricks suggested and installed in burning zone.

Jan 1, 2004

By A. P. E. Dirige

In order to maximize the recovery of ore and to save on costs in undercut mining, backfill of low cement content is used to fill the mined out excavations. This backfill mass is supported by a sillmat structure cast from cemented backfill of very high strength. The stability design of sillmats must be carefully studied to provide very effective, safe and economic mining operations. This paper presents a methodology and procedures for sillmat design based on three engineering modeling approaches: analytical, numerical and centrifuge modeling. Application of the design approach is demonstrated from a design study conducted for an underground gold mine, aimed at minimizing backfill binder content and at producing cost efficient paste fill recipes for sillmat construction. Application of the engineering design recommendations was projected to result in substantial annual cost savings to the mine operation.

May 1, 2007

By Selvia Tourn, Liliana Castro

"Abstract - Argentina, a large country with an important agriculture industry, needs an ever-increasing amount of phosphorus and potassium, as essential elements for plant growth. Current requirements are met from imports, but potential resources exist in Argentina. For example, several phosphatic occurrences are known in paleo-marine basins, the most significant of which are in Tertiary units in Patagonia. In addition, two types of potassium deposits are also known in Argentina: evaporite deposits in the Neuquén Basin at depths of 750 m to 1500 m contain 22 to 25 wt% K2O equivalent; and glauconitic sandstone containing about 6 wt% K2O has been identified in Patagonia.Several experiments were undertaken to test unprocessed phosphate rocks as slow-release, direct-application fertilizers, with good results. In addition, it is proposed that direct application of glauconitic sands would provide an efficient and economic alternative source of potassium. Tests with glauconite samples are still in progress. The existence of both phosphate and glauconitic rocks in Patagonia suggests that development of an extractive industry for these materials would not only help Argentina approach self-sufficiency in fertilizer usage, but also assist in the socio-economic development of this region."

Jan 1, 2003

By W. G. Davenport

Methods of extracting copper are evaluated in terms of innovations during the 1970's, and predictions to the end of this century are made. It is concluded that between one and two new smelters and refineries will be needed per year until the turn of the century, and that most of these smelters will be of the oxygen or oxygen-enriched flash furnace type. For converting, the Peirce-Smith converter will still predominate, but the Hoboken converter will play an increasingly important role. Five Japanese pollution control systems are described and it is suggested that much of this technology will be included in future smelting installations. Further growth of hydrometallurgy is predicted, especially for oxide ores, based on improved product metal quality and low plant cost. A n increased level of scrap resmelting is also expected.

Jan 1, 1980

By G. N. Carlson, C. H. Hazelroth, D. R. Dorrance

"Located on the north shore of the St. Lawrence River at Pointe Noire, Quebec are the agglomeration and ship-ping facilities of the Wabush Mines complex. Here, the specular hematite concentrate from the Scully Mine is received for further processing. Modern facilities for handling the ore, either to the 1plant or to stockpile, provide quick and efficient operation of the ore receiving station. Physical preparation of the ore for balling is accomplished with regrind ball mills, filters, bentonite crushing and drying facilities, pumps and related conveying circuits. Rotating table feeders deliver the reground and de-watered ore from storage bins to balling drums, where green ball or green pellet formation is achieved. The green balls are then conveyed to the indurating section. Three Dravo-Lurgi travelling grates, producing a total of 6,000,000 long dry tons of pellets per year, are used in the indurating phase of the operation. These grates, having 38 windboxes and firing at a temperature of 2,500°F, harden the pellets for shipment to various blast furnaces throughout the world."

Jan 1, 1969

By B. Loveday, G. W. Delaney, S. Cummins

"Applying DEM to prediction of tumbling mill performance is challenging because several different modes of breakage are active in the process. As our knowledge of breakage and computational capacity improve, it is worth revisiting previous simulation tasks which did not produce a satisfactorily realistic description of a measured process. At SAG 2006, we reported the simulated and measured outcomes of treating a well characterised ore in a 1.2 m diameter mill. This well instrumented, pilot scale mill at the University of KwaZulu-Natal has been combined with some new approaches to ore testing to allow different modes of breakage to be tested. The mill design allows the rate of generation of fine material to be measured in close to real time for autogenous and SAG mill charges. The updated simulation model estimates mass loss with particle evolution and embeds the cumulative damage and breakage.The simulated results are compared with the measured results. Issues such as relating modelling inputs to particle breakage characterisation data and the accuracy of the predictions of the models are discussed."

Jan 1, 2012

By P. E. Weidmark

"Energy, Mines and Resources Canada has published the first in a new series of reports that will examine selected mineral products that are imported.""Vanadium - An Imported Mineral Commodity"" looks at one of the 32 raw materials for which Canada currently is totally dependent on foreign sources of supply. Vanadium is used in Canada mainly as an alloying element in the manufacture of high-strength, low-alloy (HSLA) steels.The series will examine the supply systems for various selected imported non-fuel minerals, as an aid to developing policies that might lead to reduced dependence on external sources. Each report in the series will address a numberof questions:What countries do the mineral and its principal sub-products come from?How do they get to Canada?What are they used for?How vulnerable is the supply chain to disruption?Are there alternative sources?Are substitute materials available?In summary - how serious is Canada's supply problem for the mineral in question, and what should be done about it?Mineral Bulletin MR 188, ""Vanadium - An Imported Mineral Commodity"", is available for $3.00 ($3.60 outside Canada) from authorized government bookstore agents and many other bookstores, or by mail from the Canadian Government Publishing Centre, Hull, Quebec, KIA OS9."

Jan 1, 1981

By D. Pearcey, S. T. Vessey, V. Hegde, J. Staples

"Pellet quality has taken on a new dimension during the last ten years. Quality in the seventies was generally defined as adherence to certain physical and chemical specifications. Today, the talk is in terms of how the business is managed, how customer's expectations can be exceeded, not only in product quality, but in service responsiveness.Coke breeze and flux additions, lower silica levels, and improved furnace control practices have all contributed to the improvement of pellet physical and metallurgical properties. Statistical process control has provided additional insight into the parameters that affect pellet quality.Increased customer contact and product quality surveys have heightened our awareness of customer needs and also provide direction for quality improvement test work. Current work is focussed on improving reducibility and understanding the relationship between tumble, fired compression and metallurgical properties.This paper will review the Iron Ore Company of Canada's efforts during the past decade and describe some of its initiatives for the future.IntroductionThe Carol Pellet PlantThe Iron Ore Company of Canada's Carol Project is located in Labrador City in the southwestern portion of Newfoundland and Labrador , approximately 965 Ian northeast of Montreal. The project consists of mining facilities, beneficiation complex and a pellet plant, which began operations in 1962. The pellet plant consists of six Dravo-Lurgi straight grate machines, regrinding, filtering and balling facilities. The current capacity of the Carol pellet plant is approximately 10.5 million tonnes , while the concentrator has the capacity to produce about 18 million tonnes of concentrate.The orebody consists of specular hematite, magnetite and small quantities of limonite and goethite. The average grade of the orebody is approximately 39% iron."

Jan 1, 1991

By A. Tohn, L. May, Adham. K.

The path from process conception to commercial implementation poses significant technical, economic, and sometimes political challenges for every project team. Solving the technical challenges typically distinguishes successful projects from those that fail. Here, the authors provide an outline for technical success based on lessons learned from years of experience in process design and R&D. Challenges faced by new technology developers, with regard to design and definition, are described. Experience-based methods to avoid missteps are shared. Special emphasis is placed on the selection of viable unit operations, definition of known and unknown parameters, experimental screening of options, and piloting for scalable design information. Use of computational models to define, assist, and interpret the pilot operations and results are described. Furthermore, the value of active collaboration amongst the design, research, and owner team is demonstrated.

Jan 1, 2011

By F. Charette

Instrumentation has been developed that can monitor the strain applied to a D-Bolt up to 7.5% elongation. The technology far exceeds the limit for foil resistance strain gauges. In the laboratory the instrumentation has provided insight into the fundamental behaviour of the D-Bolt following yield. Currently the instrumentation is undergoing field trials at a number of Canadian Mines. Discussion on field results is provided with regards to significance, reliability and temperature effects.

Aug 1, 2013

By J. E. Nesset

"As an alternative to conventional dewatering by vacuum filtration and oil-fired rotary dryers, Brunswick Mining conducted extensive pilot-scale testwork on its copper, lead, zinc and bulk concentrates using a Larox Oy (Finland) automatic pressure filter. The results showed that pressure filtration readily produced final cake moistures of 6-8.5 per cent on this very fine sulphide material.An in-depth analysis examines pressure filtration in terms of metallurgical performance and projects energy savings of 78 per cent for pressure filters over the current dewatering operation. Potential energy and operating cost reductions are also estimated.IntroductionVacuum filters followed by oil-fired rotary dryers are one of the most common means of dewatering mineral concentrates. They represent, however, a level of technology which is exceedingly wasteful in terms of manpower, space utilization equipment and fossil fuel dependence. In addition, the use of thermal dryers is leading to increased environmental concerns both in plant and out.These were the primary factors which prompted Brunswick Mining to consider alternative dewatering methods as the existing equipment came up for replacement and upgrading. In late 1979, company engineers were encouraged by automatic Larox pressure filters seen at several Scandinavian operations. Subsequent laboratory tests by the manufacturer (Larox Oy of Finland) on several concentrate samples were sufficiently promising for Brunswick and Noranda to lease a trailer mounted filter-lab unit and a technician from Larox for a five-week period. Extensive on-site testwork on all four Brunswick concentrates (zinc, lead, copper and 'bulk' lead-zinc) confirmed the potential of pressure filtration."

Jan 1, 1982

By K-A. Adamson

If fuel cells and hydrogen are to become a mass market reality a substantial amount of further research and development needs to be undertaken. Work in hydrogen storage, production, the economics of all aspects of fuel cells and hydrogen, materials balances, and product integration are just a few of the areas that are under focus. Setting R&D targets, and providing R&D funding are therefore areas that are central to the long term development of the market, and areas in which a number of governments worldwide are highly active. Some governments, such as Japan and Korea, have set a number of very ambitious, highly focused, long term targets and are backing this up with substantial funding, others such as the EU are working on a more integrated approach, wrapping some fairly fundamental R&D into large integrated projects which run in combination with a number of other market aspects, such as public acceptance and roadmapping. The US is slightly different, in that although is has a number of long term programmes and targets, FreedomCar and SuperGen being just two, the levels of funding are set annually with the passing of each years Fiscal Budget. This paper takes three high profile regions and analyses the R&D targets and funding levels for fuel cells and hydrogen. Criteria that will be looked at include: Time frame of target(s), level of ambition, funding issues, including: Funding windows, levels available, funding barriers, overall programme goals. The added value to this paper is that it will provide a clearer picture of where each region is heading, what are its strengths and weaknesses, in terms of R&D and where there may be areas for potential international collaboration.

Jan 1, 2005