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By Rodney S. Read

This paper outlines a reasoned argument why no large-scale fracturing or faulting will be induced in the host rock by a deep geological repository (DGR) for nuclear fuel waste. Four DGR designs in three possible host rocks, including crystalline and sedimentary rock types, are considered. The reasoned argument draws from results of previously conducted thermal- mechanical analyses and new scoping calculations, along with evidence from experiments conducted in Canada and elsewhere. It is concluded that large-scale fracturing in the far-field is implausible given the expected in situ stress conditions in relation to rock strength. Near-field damage development and fracturing are expected in DGR scenarios in the different rock types, but these near-field effects are not expected to lead to large-scale fracturing that could compromise the integrity of the DGR and surrounding rock mass. Additional analysis and characterization activities are recommended to further validate the reasoned argument. Thermo-poroelastic loading of the rock mass is identified as one possible driving mechanism that should be studied further.

May 1, 2009

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 Suping Yao, Chuanyu Jiang

In the last decade, the copper industry in China has witnessed a significant change. The capacity and production of refined copper has grown remarkably from 1.5 million tons in 2002 up to 5.88 million tons in 2012. And now, China has become the biggest copper producer in the world, counting about 30% of the global refined copper production. This paper summarized modern copper smelting and converting technologies employed in China copper industry, such as OT flash technology, TSL (ISA/Ausmelt), SKS bottom blowing, Jinfeng side blowing, etc…This paper also presents some key development and improvement of these technologies up to date from their practical application in China, what will contribute as great value to any new / or renovation copper smelting projects down the road. As an engineering company in China, NERIN has been involved in many of these projects in the past decade, played an important role in the engineering works and accumulated intensive experiences. NERIN is one of the best choices for the world clients in the copper industry, providing quick engineering service, delivering cost effective projects.

Jan 1, 2014

By Neil Westoll

Extensive Global Network ?Working together, AECOM provides clients with a unique blend of global reach, local knowledge, innovation and technical excellence. ?43,000+ team members worldwide ?450+ offices ?100+ countries ?6 continents The Changing Climate ?Climate change is ?official??IPCC 2007 ?Climate change will create instability, change and opportunities ?Companies that are resilient and adapt will survive and evolve ?CO2/GHG emissions will be curbed by legislation ?How will this affect the mining industry? ?How can the mining industry adapt to the new realities?

May 1, 2009

By Gary Walters, Thomas Gonzales, David George, William Davenport, Andreas Siegmund, Suping Yao, Shijie Wang

The previous survey of world copper smelters was in 2016 (Copper, 2016). The copper smelting industry has grown and improved considerably since then, including continuing growth in China and modernization in Japan (Extraction, 2018). Outotec flash smelting and Outotec flash smelting/Kennecott - Outotec flash converting continue to be adopted while newer processes continue to be adopted in China. In addition, some of the world's original flash furnaces have been completely rebuilt (Extraction, 2018). This paper provides recent industrial production data and discusses these new developments. INTRODUCTION A world copper survey was redone in 2016 after a thirteen year lag since 2003. Some of the notable changes were the significant increases in production particularly from China. Since then, several smelters have gone through modernization processes and decommissioning of older technologies. This paper will review the notable changes since the last publication at Cu2016. In the last paper, Copper Smelting: 2016 World Copper Smelter Data, the author gave an audible sigh after observing that copper smelter sites as well as new and notable smelters have been spreading like wildfire in China since 2003. Indeed, seeing is believing. Figure 1 shows the Ningde Copper Smelter (double flashing, 400,000 MT Cu/Year capacity) that started up producing copper in 2018; Figure 2 shows the Nanguo Copper Smelter that is under construction with 300,000 MT Cu/Year capacity (first phase, side blown smelting and continuous top blown converting). We should not only admire the Chinese copper industry’s significant technological developments, but also the copper price support that it has provided throughout this century.

Jan 1, 2019

By R. A. McIvor, R. S. Rafuse

"INCO Limited purchased a custom designed mobile hoist rope winder/tensioner in 1988 from TimberLand Equipment Limited to handle Large hoist ropes and serve as an emergency hoist. This paper describes the operation of the winder/tensioner and some of the different applications that the machine has been used to handle large loads.IntroductionINCO Limited operates 24 mine hoists in the Ontario Division and has approximately 50 miles of mine hoist rope hanging in the shaft plus an equal amount on spare reels. The mine hoist ropes range in size from )( inch to 2.305 inches in diameter with the majority being 1 3/4 inches and above. Prior to the procurement of a new high powered winder/tensioner in 1988, the mine hoist ropes were handled with a variety of methods and equipment using hydraulic or pneumatic powered reel winders. The largest such reel winder has a pull rating of 8000 Ibs and travels approximately 40 ft/min. Head ropes for the tower mounted friction hoists were installed and removed using a magazine on the hoist drum to wind and unwind the rope because the loads were greater than the capacity of the existing machinery. It was recognized that a large high capacity machine would improve the productivity for handling the larger hoist ropes and a feasibility study was undertaken to determine the parameters for such a machine."

Jan 1, 1995

By D. Marotte, M. David

"A new exploration procedure is proposed for volcanogenic massive sulphide deposits of the Abitibi belt. ""Samples"" of acidic volcanic rocks (Si02 > 60%) were compiled from the literature. From the 574 samples collected, 322 were used in each of a number of experiments. Forward inclusion linear discriminant analysis performed on the untransformed geochemical data shows a general depletion in Na20 and CaO along with an enrichment in MgO for a ""proximal"" group of samples relative to a ""distal"" one. The percentage of misclassified samples reaches 20% to 30%, but test sets shows good stability.The exploration procedure was applied to the Normetal deposit, where the authors took 160 samples during the summer of 1977. It quickly leads to the definition of targets for more detailed exploration together with a good recognition of the old known deposit.IntroductionVolcanogenic massive sulphide deposits in the Abitibi belt (Quebec) are mainly found in rhyolites or acidic pyroclastics in the uppermost portion of a calc-alkaline volcanic series (Descarreaux, 1972). The deposits are thought to have formed syngenetically by the action of volcanic hydrothermal exhalations during the waning episode of a felsic volcanic cycle (De Rosen Spence, 1976). Alteration pipes of disseminated sulphides are commonly present. Metal deposition from hot springs, initiating convection cells in a submarine environment, may have been the dominant process in ore formation (De Rosen Spence, 1976)."

Jan 1, 1981

By J. L. Casado-Sánchez

Financial capital is highly volatile and if the investor does not get adequate compensation for the risk faced he may consider withdrawing his capital assets from the company and consequently produce a structural change in any sector of the economy. We study the variation in profitability of assets in terms of the changes that occur in the markets. The choice of models used is justified by the extensive theoretical and empirical use of them throughout the history of financial economics. We have used the capital asset pricing model (CAPM) and the model based on the arbitrage pricing theory (APT) to determine the beta value. These models have been applied to the monthly returns of 27 mining companies listed on the New York Stock Exchange (NYSE) or London Stock Exchange (LSE), using data from the period covered from January 2006 to December 2010. The results of time series and cross sectional regressions for CAPM and APT produce some errors, suggesting that many companies have failed to obtain an adequate cost of capital. Also the results show that higher risk firms tend to have lower profitability. These findings make it unlikely to be maintained over the long term the current status and could drive structural change in the mining sector in the form of mergers.

Aug 1, 2013

By C. Pichler, J. Antrekowitsch

During the production process of steel and other metals a lot of different by products are generated in high amounts. Some of these residues are recycled to recover valuable metals like zinc, lead, copper and others. Especially the treatment of steel mill dust presents a great challenge. The need for new technologies can be seen in the wide range of available recycling concepts for steel mill dust treatment, however most of them have significant disadvantages. An example is the waelz process, which generates about 650 to 700 kg slag during the treatment of 1000 kg steel mill dust. This so called "waelz slag" must be dumped in the most cases. To avoid a landfilling all generated products must be able to get reused in another application. A so called "Zero Waste Process" can be reached with the "2SDR Process" (Two Step Dust Recycling Process), in which the dust is treated on an liquid iron bath generating cast iron, inert slag and zinc oxide. These products have a further usage and can also be sold. The paper focuses on the process development through trials in lab and technical scale up to planned pilot scales, with an accompanying characterisation of the generated products were done.

Jan 1, 2014

By A. L. Karyakin

The report focuses on the process measurements of the mass of rock in the bucket power shovels and dragline excavators. The mathematical models are suggested of AC and DC electric drives of excavators. These models are a basis for calculation methods of the electric drive electromagnetic torque. The design schemes of mechanical equipment of excavators considered to account the situation of bucket in the plane of the boom. The methods of static moment allocation and identification of the excavator technological operations are developed. The results of the work are experimentally tested on power shovels with bucket capacity of 12 and 18 m3.

Aug 1, 2013

By F. J. West

This paper deals with Jones & Laughlin Steel Corporation's new Adams mine, near Kirkland Lake, Ontario. After a brief discussion of ore structure, type, reserve tonnages, etc., the main body of the paper discusses the establishment of an open-pit limit based on economic considerations. The method used by J & L to arrive at an economically sound open-pit boundary its outlined fully. Physical limitations to open-pit boundaries are mentioned briefly. The paper concludes with a few remarks on the mining equipment in use and on its productivity

Jan 1, 1966

By G. Chung, W. Petruk, D. Doyle

"A series of tests was conducted on Carol Lake iron ore, which contains about 38 wt % hematite and 19 wt % magnetite, to establish a flowsheet for high weight yield by spirals. A pilot plant was run in parallel with the IOC concentrator to simultaneously test two flowsheets on the same feed material. The IOC concentrator processes the ore by treating it directly in a spiral circuit, whereas the pilot plant used a laconite flowsheet which had a low intensity magnetic separator (LIMS) at the front of the circuit. The LIMS produced a non-magnetic (hematite-rich) product and a magnetic (magnetite-rich) product prior to treating the ore in two separate spiral circuits. The results from about 150 tests were evaluated by chemical assays and materials balancing techniques, and a selected test was evaluated by the image analysis and materials balancing technique.The image analysis and materials balancing evaluation showed that a higher hematite recovery was obtained by the hematite spiral circuit than by the IOC concentrator spiral circuit, and a slightly lower magnetite recovery by the magnetite spiral circuit than by the IOC concentrator spiral circuit. Furthermore the hematite recovery by hematite spirals was higher than the magnetite recovery by magnetite spirals. The better hematite recovery was achieved because a higher liberation is obtained for hematite than for magnetite, and the hematite in the Carol Lake ore has a narrower grain size range than magnetite. Consequently, better spiral control can be maintained when processing a hematite-rich spiral feed, than when processing a magnetite-rich spiral feed. Since the feed to the IOC concentrator spiral is a mixture of hematite and magnetite, an intermediate hematite recovery is obtained by the IOC concentrator. INTRODUCTIONA study of characteristics that affect recoveries of hematite and magnetite from the Carol Lake ores of the Iron Ore Company of Canada (IOC), was carried out in connection with a project on designing a flowsheet for maximum weight yields. A pilot plant using a taconite flowsheet was run in parallel with the existing IOC concentrator which uses a classical iron ore flowsheet. About 150 tests were run to compare iron recoveries and weight yields by the spirals in the two flowsheets. Better iron recoveries were indicated for the taconite flowsheet, but the results were not consistent and the reasons for the observed differences were not apparent. The material from one test (Test 61), which gave better iron recoveries for the taconite flowsheet, was evaluated by the image analysis and materials balancing technique. A suite of samples was taken from 5 points in the IOC concentrator and from 8 points in a pilot plant (taconite flowsheet). The samples were analyzed to compare the behaviours of the Carol Lake hematite and magnetite in the spirals of the two flowsheets. The results provided a sound basis for further tests in designing a high weight yield flow sheet."

Jan 1, 1993

By Guy Chevalier

QCM?s pellet plant, located in Port-Cartier, Quebec, produces up to 8.6 million tons of iron ore pellets annually. Four different types are produced: three for blast furnace operations and one for direct reduction furnaces. The paper presents the scientific approach that led to the installation of new process equipment to improve the reducibility of direct reduction pellets (DR pellet). The findings, the equipment selection and some post start-up modifications are presented. This low silica DR pellet is used in Midrex and HyL shaft furnaces. A good DR pellet has to meet strict chemical, physical and metallurgical specifications. An important metallurgical property is its ability to release oxygen when exposed to reducing gases. Considering that the market for DR pellets is expanding and being aware that reducibility is critical for our clients, a program to improve the latter was undertaken. Test work showed that one factor which has a negative effect on reducibility is the proportion of particles larger than 75 microns. Knowing that the best way to reduce the amount of coarse particles was to close our open grinding circuits, we began evaluating the most suitable classification equipment applicable to our process operations. We settled on hydro-classifiers based on their very sharp cut and their low operating costs. In light of the hydro-classifiers performance it was also decided to replace the hydro-cyclones of an already closed circuit.

May 1, 2003

By L. Voisin, G. Damm

"In order to develop a new pyrometallurgical process for eliminating detrimental arsenic and antimony from the impurity-rich matte produced from copper concentrate, and for treating the occasionally generated speiss in nonferrous smelting processes, the phase relations in the Fe-Cu-S-As-Sb system saturated with carbon at 1473 K were investigated. The distribution of elements between the condensed phases at the miscibility gap, where three equilibrated phases of iron-rich alloy, copper-rich alloy, and matte coexist, were also studied. The investigation was carried out by performing a series of laboratory scale experiments in an electrical furnace at 1473 K, followed by a quenching method on the final stage. The samples obtained from the experiments were analyzed by using Inductively Couple Plasma (ICP), Atomic Absorption Spectroscopy (AAS) and Carbon Infrared Spectrometry (CIS) techniques.The results were compared with previous investigations for the Fe-Cu-S-As-C and Fe-Cu-S-Sb-C systems and discussed on the basis of the molar fraction distribution for both arsenic and antimony in the matte phase at five different matte grades. It is expected that by using this phase separation technique it might be feasible both, the cleaning of a complex copper matte and the elimination of arsenic and iron together with an acceptable amount of antimony into the iron-rich alloy phase, which can be discarded as a harmless and smaller deposit."

Jan 1, 2014

"The South African Mineral Resource Committee (SAMREC), a Working Group of the SAMREC/SAMVAL Committee (SSC), under the joint auspices of the Southern African Institute of Mining and Metallurgy (SAIMM) and the Geological Society of South Africa (GSSA) developed the SAMREC Code. The Code sets out minimum standards, recommendations and guidelines for public reporting of exploration results, mineral resources and mineral reserves in South Africa. It is applicable to the reporting of all styles of solid mineralization or economic deposit. However, certain commodities, namely coal and diamonds, have specific additional reporting requirements. The Code does not apply to oil, gas or water."

Jan 1, 2003

By Maurizio Violo, Arjan Beqiraj, Umberto Masi

"Abstract - Four main podiform occurrences of chromite have been distinguished in the ultramafic Bulqiza massif, Albania; they are associated from the bottom to the top with: i) basal harzburgites (lower tectonite sequence), ii) dunitic lens-bearing harzbugites (middle-upper tectonite sequence), iii) layered chromitite-bearing dunites of transitional zone, and, iiii) the stratigraphically lowermost part of the magmatic section. However, only the occurrences hosted by rocks ii) and iii) are economically important.Chromite compositions similar to those of other podiform chromites are bimodal. Thus, chromites from occurrences ii) and iii) are richer in Cr than chromites from the other two occurrences. Accessory chromite disseminated throughout the massif is richer in Fe than orebody chromite, displaying similar range of the Cr/Cr+Al ratios, with accessory residue chromite matching the characteristic (Cr/Cr+Al >0.6) range of type-III Alpine peridotites. Both orebody and accessory chromites show compositional ranges correlating with host-rock compositions, i.e., the Cr-rich chromites are hosted by the most refractory ultramafic rocks. Therefore, the Cr/Cr+Al and Mg/Fetot (Cr/Fetot) ratios of chromite are useful for exploration of high-grade, metallurgical chromite ore at Bulqiza and in other massifs of similar geodynamic setting."

Jan 1, 2000

By E. S. Moore

GOLD was discovered previous to the year 1900 on the east shore of Emerald lake, Afton township, Timagami Forest Reserve. It was found in a small cavern in banded iron formation, close to the water's edge. This occurrence of gold was mentioned in several reports that referred briefly to this area, and prospectors evinced considerable interest in the region. It was not, however, until the Golden Rose Mining Company, which was incorporated in 1909, started operations that much work was done on the property. In 1915-16, this Company, under the direction of E. J. Townsend, the President, did a considerable amount of work. A small mill was built and ore was extracted from pits, trenches, and a one~ hundred-foot shaft. In 1927, Afton Mines, Limited, was incorporated to take over the property, and about thirty men were employed for a time. During 1934, the New Golden Rose Mining Company was organized to handle the property, and the Consolidated Mining and Smelting Company of Canada, Limited, undertook to develop the mine. In March of the following year, this Company began deepening the shaft from 100 feet to 500 feet. A considerable amount of drilling had previously been done on the hill of iron formation in which the mine is located. Further drilling was done from the surface, and altogether about twelve holes have been put down to test the formations. Over 2,000 feet of drilling has also been done from the underground workings. The mine is now known officially as the New Golden Rose mine, although to many it is better known as the Afton. To reach the property during the summer months, there is a boat trip of about thirty miles from Timagami, a wagon-road portage of one mile to Obabika lake, a boat trip of ten miles on this lake, and finally a wagon-road portage of one and one-quarter miles to Emerald lake. The mine lies about three-quarters of a mile down the east shore of the lake. A 75 h.p. Diesel engine and compressor were taken in over this' route last summer, and it is evident that the transportation problem is quite a serious one. Airplanes have been much in use, and a winter road runs from the mine to Chudleigh, on the .Canadian National railway near Sudbury.

Jan 1, 1936

By A. C. Drost

The mining industry has been put under closer scrutiny in recent years, which has led to the adoption of a plethora of initiatives in countries around the world and by international organizations, some voluntary and others mandatory, governing economic, ethical, social and environmental practices of this industry. In order to plan appropriately, secure project financing, build value and manage risks, it is imperative to identify and understand the application of this new and evolving regime, which can be described under the general label of corporate social responsibility (?CSR?) law, and to incorporate compliance policies into the day-to-day operations of mining companies. Our paper and presentation will describe this new legal framework, which includes both ?soft? law and ?hard? law adopted at the international and domestic level that governs the actions of mining companies, particularly when operating in developing countries. While the notions of hard and soft law may seem abstract and grounded in legal theory, this paper shall demonstrate how these concepts concretely apply to companies in general, and to mining companies in particular. An analysis of the recent case law in this area as well as examples of corporate ?best practices? will illustrate the application of this body of law. As will be demonstrated through the case law, non-compliance of CSR law (both ?soft? law and ?hard? law) can lead to economic penalties, difficulties in accessing capital, loss of social licenses and even the withdrawal of permits and concessions. This confirms that now more than ever, ethics and sustainable practices in mining are fundamental to building a successful business model.

Aug 1, 2013

By S. E. El-Alfy, John Starkey

"The Iron Ore Company of Canada treats up to 125,000 t/d of iron ore at its Carol Concentrator in Labrador City, NF.A complete water balance study in the concentrator was done to show how to reduce the consumption of fresh water, to improve metallurgy in the magnetic separation (mag) plant, and to help reduce maintenance costs for the reclaim water and tailing pumping systems.The study showed that more than 60% of the water used in the mill was internally recycled dirty water from dewatering cyclone overflows, and that water reduction was closely tied to the effective use of these internal reclaim pumping systems. In addition, new operating parameters were set for the 4 -15,000 USGPM reclaim water pumps which should save over $100,000 per year in maintenance costs.IntroductionThe study described in this paper was set up for the purpose of lowering water usage in the concentrator, and to reduce tailing and process water pumping costs (operating and maintenance). Another benefit was also expected, namely, to improve magnetic separation efficiency through better water and density management of magnetic separator feed streams.The procedures selected to perform this work were: ( 1) to prepare accurate, as built flowsheets of the entire iron recovery process, including fresh and process water systems, (2) to calculate normal material balances in all circuits at full production, (3) to use the computer spreadsheet model so generated, to evaluate specific ways to reduce water consumption and (4) to re-evaluate metallurgical performance and operating parameters in the light of this information.Overall control of the 28 spiral iron recovery lines was found to be excellent because automated start up and shut down of the individual lines had been incorporated in the design from the start. Because production rates can vary due to sales requirements, mine and mill maintenance delays and hardness variance, the mag plant (which treats spiral tailings) must deal with a wide variety of operating conditions. Good water management therefore is a key item in achieving high recovery of the fine free magnetite which is too fine for recovery in the spirals.In order to make the study as accurate as possible, process data for major flows was reviewed by metallurgical staff and then by mill supervisors. The operating picture of the concentrator so generated was judged to be a good estimate of the mill at full production. By changing key inputs, the variance of process water demand and tailing slurry produced for several other operating conditions were studied.The usefulness of this exercise has prompted this present presentation to be made. Older plants by nature have undergone many revisions as operators have worked through ore changes, market changes, labour cost increases and the availability of new equipment, to improve their operation. Sometimes therefore it is necessary to stop and reassess what is happening in a plant in order to continue the never ending work of process optimization. The techniques used here were ideally suited to the gravity/magnetic concentration flowsheets used, but there is no reason why similar studies could not be done in other process plants.The authors of this paper hope that this experience at IOC will be helpful to others who face similar challenges in the pursuit of excellence in their processing plants."

Jan 1, 1995

By J. Drenda

The model for methane removal from the workings directly behind an advancing longwall as presented in this paper may be used for U-ventilated cross or length-wise systems of longwall advance, starting from the boundaries of the extraction field. In mines with high methane concentrations, Uventilated longwall extraction from the boundary of the extraction field produces a methane risk. The risk is manifested by a higher methane concentration at the end of the longwall, upper gate and incline. The methane in increasing concentrations, which is emitted mainly from the workings with caved areas, appears towards the end of the longwall and in the upper gate. The graphical model of the longwall provided includes both the workspace of the longwall and the caved area. Based upon a model of the rock distribution in the cave, a ventilation model comprising two standard air splits and large number of crosswise air splits has been constructed. Simulations indicate that if the shearer is not present in the longwall, the air distribution in the caved area is symmetrical. The presence of the shearer, both at the bottom and the top of the longwall, causes an asymmetrical air distribution in the cave, that is the asymmetrical flows in the goaf and longwall workspace and in the inflows and outflow between those regions. This phenomenon causes an increase in methane concentration at the end of the wall and at the upper gate. The methane removal method proposed for workings with a caved area directly behind the advancing U-ventilated longwall, starting from the boundary of the field, consists of the removal of methane-air mixtures from the caved area with the boom pipes. These booms may be of several meters long and may be extended if necessary. The insertion of the boom pipes into the cave towards the end of the longwall and connecting them with the general methane removal system creates negative pressure causing a change in the depression field, which is the aerodynamic potential field in the goaf area around the ends of the boom pipes. This will promote the extraction of the methane-air mixture from voids and the goaf cracks, and the area from which methane is being extracted may extend to the side of the cave. This is a positive phenomenon, which could result in the methane flow from the goaf into the airflow in the longwall workspace decreasing or even stopping. A reduction in the methane flow into the longwall workspace with extractions booms will be advantageous for the production continuity. Based on the floor load model for the rocks in the cave and the methane-removal boom load model, the value of the force required to move the boom behind the advancing wall has been calculated. Strength calculations for the pipe were performed using a finite elements method. The analysis results, as well as the comparison of the pipe material effort to the strength parameters of steel, which can serve as piping material (for the assumed load conditions), lead to a belief that the proposed boom construction satisfies the strength requirements.

Aug 1, 2013