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By C. Landolt

Inco's Copper Cliff Smelter Complex produces some 11 5,000 tonnes per year of nickel and 120,000 tonnes per year of copper. The Smelter flowsheet has changed a number of times over the years. The most recent changes were effected in the mid-1980's in response to new realities in metal markets and heightened awareness about the workplace environment. By 1994, the flowsheet will undergo yet another metamorphosis as part of Inco's SO2 Abatement Program. The paper discusses the improvements implemented during the 1980's and projects the processing in the Smelter through 1994.

Jan 1, 1993

By Scott A. Stebbins

This Bureau of Mines publication presents a method for estimating capital and operating costs associated with the exploration, mining, and processing of placer deposits. To ensure representative cost estimates, operational parameters for placering equipment and basic principles of placer mining techniques are detailed.

Jan 1, 1987

By P. Hanniala, S. Harkki, B. Andersson

"The Outokumpu Flash Smelting Process was put into commercial operation in 1949. The original process was based on the use of preheated air. The adoption of oxygen enrichment of the flash smelting process air in 1971 was a crucial improvement, especially for smelter capacity. Oxygen use according to the Outokumpu method means selection of the most suitable oxygen content for the process air on the basis of the concentrate composition, capacity and matte grade. The furnace is not bound to only one fixed degree of process air oxygen enrichment; the oxygen content may vary from 21% to 100%.The degree of oxygen enrichment and the matte grade are the most important process parameters in reducing the operating costs of the whole system, including smelting, converting and acid production. Raising the matte grade allows more efficient use of the reaction heat in the smelting stage. Sulphur is recovered in a high-strength, constant-flow gas stream. The blowing time in the converters is reduced considerably.Oxygen enrichment and high matte grade improve the energy efficiency of the plant complex as long as the surplus heat from the system is not wasted. When the operating costs and investment expenditure of the total plant complex are taken into account, a reasonably high degree of oxygen enrichment (35-80°/0) is the best alternative in practice. Existing operating smelters have achieved single-stream thoughputs of over one million t/yr of concentrates.HistoryLocal capital and operating costs as well as lower energy consumption per unit of metal produced are now the crucial factors in determining the choice of process. In the late I940s, the same reasons prompted Outokumpu to develop the original flash smelting process in Finland. Between 1900 and 1940, very few technical changes in pyrometallurgical copper production took place. However, the commercial use of the flash smelting technique began a new era in metal extraction from sulphide concentrates. The characteristic feature of the method is that the concentrate is smelted in suspension: this offers the most favourable conditions for heat and mass transfer, and thus high reaction velocities. Outokumpu was the first to exploit the known advantages of flash smelting in a commercial installation at Harjavalta in 1949."

Jan 1, 1982

By A Ross, B De Rivaz

The results of full-scale tests on precast segment made at University of Roma are presented. The segments were cast using fibre-reinforced concrete produced without any traditional reinforcement, by using fiber made in high-strength steel and a new type of anchorage.Bending tests were performed in order to check the bearing capacity of the segments under the flexural actions; these occur during de-moulding, handling, storage phases as well as in the in situ condition (due to asymmetric soil pressure). Furthermore, point load tests simulating the TBM thrust were performed, in order to study the construction phase (excavation).The results show that the segment response largely respects the material testing and design advice according to the Fib Model Code 2010. Providing engineers, precast operators and builders confidence in material strengths and design methodology.CITATION:De Rivaz, B and Ross, A, 2014. Full-scale tests on precast tunnel segments made in concrete reinforced with high-strength steel fibres, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 469–476 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By Jan Visman, S. J. Aresco

INTRODUCTION The accurate sampling of coal, as with most minerals, is a difficult task. Coal is a heterogeneous material made up of different types of coal and varying amounts of mineral matter. The product as mined may contain all the layers of coal and impurities found in the seam as well as portions of the stratas above and below the coal seam. The preparation plant is the device to size, crush, and/or remove impurities so the coal may be shipped as a salable product. Sampling may be needed at many stages in the preparation process. Although this chapter is primarily concerned with sampling in connection with preparation processes, the principles apply to all coal sampling. The main reasons for sampling in connection with coal preparation are: 1) To determine the washability characteristics of the raw coal by means of float and sink tests. These may be used for the design of a preparation plant, prediction of results to be obtained, or monitoring raw coal delivered to the plant. 2) To check the performance of various operating units in the plant, either by float. and sink tests or chemical analyses. 3) To determine the analytical characteristics of the products produced, such as moisture, ash, Btu, sulfur, etc. HISTORY The earliest accepted methods of sampling coal in the United States were given in US Bureau of Mines (USBM) publications by J. A. Holmes,l G. S. Pope,2 and A. C. Fieldner.3 The American Society for Testing and Materials (ASTM) more or less adopted the methods proposed by USBM in their Standard D-21-1916 and it remained a standard for many years. Briefly, this standard called for a 500 lb (227 kg) sample for coals less than 94 in. (19 mm) in size and a 1000 lb (454 kg) sample for all coals over 94 in. (19 mm) in size. No mention was made of increments, but there was an instruction that the sample should spread over the coal

Jan 1, 1979

By Thomas W. Camm

In this U.S. Bureau of Mines report, mine and mill cost models are presented to make quick estimates of the cost to develop mineral deposits in the desert region of the Southwest United States. Regression analysis was used to generate capital and operating cost equations for each model in the form Y = AXB, where Y is the cost estimated and X is the assumed daily capacity in short tons. A and B are constants determined by the regression analysis. Each is broken down into 11 subcategories to facilitate escalation of costs for inflation and to increase their versatility in economic evaluation work. This report contains 2 open pit models, 6 underground mine models, 11 mill models, and cost equations for access roads, powerlines, and tailings ponds. In addition, adjustment factors for variation in haulage distances are provided for open pit models and variation in mining depths for underground models.

Jan 1, 1991

By A D. Price, W J. Germs, O Patterson, T R. Weaver

"Understanding controls on groundwater and surface water flow and quality at mine sites throughout all mine stages is critical to effectively manage environmental impacts over the entire mine life. Monitoring forms is an essential component of this proof of understanding. Typically, monitoring programs at mine sites have been developed in the framework of existing conditions. However; recognition of the challenges of climate change and the performance of mines during recent extreme events in Australia has highlighted the need to develop monitoring programs that are resilient and responsive to changing environmental conditions. Water monitoring programs need to be effective under a range of environmental conditions, potentially not historically experienced.This emerging challenge requires cross-disciplinary teams to work together to understand issues including: representativeness of background conditions to longer-term conditions at the mine site sensitivity of mine and closure designs to changing climate and hydrologic conditions methods of performance (eg water quality or quantity) failure during extreme climate events such as flood or extended drought.These understandings come together in a detailed conceptual and, in many cases, numerical hydrologic model that considers the mine-water environment under a range of conditions. The groundwater, surface water and water quality monitoring programs that are developed from the conceptual model need to be sufficiently responsive to be effective in the face of such changing conditions, with results in turn informing the conceptual model. Extended drought, major floods and changing weather patterns can alter recharge and discharge areas, oxidation profiles and ultimately, the contaminant flux estimates that would have contributed to mine design parameters and performance. Unless these effects are considered in the spatial and temporal design of the monitoring program and within the parameters monitored, the resultant program may fail to capture data that are critical to evaluating environmental impacts from mine sites.Developing and implementing a water monitoring program that considers these issues can build confidence in mine performance under a range of conditions, leading to increased confidence by all stakeholders in long-term mine performance during and after closure.CITATION:Weaver, T R, Price, A D, Patterson, O and Germs, W J, 2013. Developing resilient water monitoring programs in changing climate conditions, in Proceedings Water in Mining 2013, pp 109-114 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

By A. D. Kalogeropoulos, T. N. Michalakopoulos

This paper deals with the numerical simulation of rock cutting laboratory tests using the discrete element method. The main objective is to provide a method for calibrating numerical DEM models of rock cutting in a systematic way so that realistic results are yielded. The numerical models are developed with the discrete element code Yade, which models rocks as a collection of bonded spheres. The models are calibrated in a four-step process based on the design of experiments method and optimization. The calibrated models are evaluated both quantitatively and qualitatively against actual laboratory cutting tests, in terms of the ratio of the simulated mean cutting force to the actual one and the cutting force time series, respectively. The fully calibrated models showed that the simulated cutting process matched qualitatively the actual cutting force recordings and underestimated the mean cutting force by approximately 3%. It is concluded that well-calibrated numerical simulations of the rock cutting process can provide not only a better understanding of the process itself but also quantitative data regarding the cutting force and energy requirements.

Dec 28, 2022

By J Zhou

Based on the mineralogical characteristics and mineral processing techniques required, gold ores can be classified into 12 types, including gold placers, quartz vein-lode ores, oxidized ores, silver-rich ores, iron oxide copper gold ores, porphyry copper gold ores, iron sulphide ores, arsenic sulphide ores, antimony sulphide ores, bismuth sulphide ores, telluride ores and carbonaceous sulphide ores. The bulk mineralogy and gold deportment of each ore type is different and may have a significant impact on ore processing and metal extraction. This paper summarizes the bulk mineralogy and gold deportment in some major types of gold ores and discusses the potential impact of gold deportment on gold metallurgy.

Jan 1, 2011

By Ronald L. Wiegel

In the 2000 page Handbook of Mineral Dressing by A. F. Taggart, the subject of material or metallurgical balances is covered in only six pages of eve-straining type. Although Taggart's work was compiled before 1945, and there has been significant progress since then in most areas of mineral processing, the practicing metallurgist's approach to metallurgical balances remains exactly the same as described in those six pages. There are several portions of Taggart's text appropriate to introduce the subject of this paper which I would like to quote: "Milling Calculations. Computations of per¬formance in milling are complicated by the fact that it is a continuous rather than a batch operation, that the quantities of solid materials handled are large and usually mixed with water, hence difficult or impos¬sible to weigh. Fortunately it is possible to determine many facts concerning perfor¬mance without knowing weights, if the value of various constituents is known in some common unit, e.g., the content of some par¬ticular metal or mineral, or of water, or some ingredient soluble therein, or of par¬ticles of a particular size or falling within some particular size range, or the like."

Jan 1, 1979

By J. S. Browning

Laboratory and pilot-plant tests of spodumene-beryl pegmatites of the Kings Mountain, N. C., area resulted in development of a new and improved method by the Bureau of Mines for separating and recovering spodumene, mica, and beryl. The process was successfully applied to other domestic pegmatites and a spodumene flotation-plant tailing containing about 0.5 percent beryl. The method comprised soap flotation of the spodumene, using combinations of sodium fluoride and lignin sulfonate as conditioning agents to recover 80 to 85 percent of the contained lithia in concentrates assaying over 6 percent Li20. About 80 percent or more of the beryl was retarded in the spodumene tailing. The beryl subsequently was activated, floated, and cleaned in a secondary circuit to yield beryl concentrates containing 6 to 7 percent BeO. The tests also demonstrated that a good recovery of high-grade mica could be produced.

Jan 1, 1961

By Norbert Patzeh

The demand for nickel is growing and will continue to do so for the foreseeable, future. This will make the construction of new leaching and smelting plants necessary. This paper described a number of possible alternative processes. The first projects with new technology are currently undergoing trials and feasibility studies. Experience from other industrial sectors and from existing plants is being incorporated into these investigations. The question is, to what extent the old nickel producing concepts will continue to be applied in the future. Keywords: Latcritc, rotary kiln, cyclonc rcactor, dust processing

Jan 1, 2004

By A. R. Miller

A fuel cell locomotive incorporates the advantages of its competitors, namely catenary-electric and diesel-electric units, while avoiding their disadvantages. It possesses the environmental benefits, at the vehicle, of an electric locomotive but the higher overall energy efficiency and lower infrastructure costs of a diesel locomotive. The natural fuel for a fuel cell is hydrogen, which can be produced from many renewable sources or via nuclear energy, and thus a hydrogen-fuel cell locomotive will not depend on imported oil. Hydrogen produced from renewable primary energies or nuclear energy would provide a totally zero-emissions vehicle, that is, with zero carbon in the energy cycle. A project partnership among Vehicle Projects Inc of the USA, and South African partners Anglo American Platinum, Ltd, Trident South Africa, and Battery Electric, has designed and is launching a series of five prototype fuel cell-powered mine locomotives.

Jan 1, 2012

By Jue Kou, Lei Yu, Bern Klein, Lusheng Zhou, Chunbao Sun, Genzhuang Li, Reem Roufail, Amit Kumar

Magnetic liners can improve the performance of ball mills by increasing grinding efficiency, extending service life, and reducing maintenance costs. Despite their importance, the fundamental understanding and the quantitative investigation on the effects of the magnetic liners has not been addressed in the literature. This paper addresses this gap by studying charge motion, and how the use of a magnetic liner affects the breakage mechanism of the mill, using discrete element method (DEM) modeling and the Hertz-Mindlin contact model with relative velocity dependent (RVD) rolling friction. Charge motion was modeled under different mill speeds. Compared to conventional steel and rubber liners, the charge motion in the magnetic liner mill was predominantly cascading. Quantitative analysis of the energy dissipation within the mill was conducted to investigate mill breakage. Regardless of speed, over 50% of the total energy dissipation in the magnetic liner mill was in the form of abrasion and attrition. The results highlighted the appeal of magnetic liners in secondary and regrinding application, where abrasion and attrition are considered more efficient in the fine material breakage, and where impact is ideally minimized to reduce mill wear. A number of experiments were conducted to assess the effect of different model parameters on the performance of the magnetic liner mill. The highest abrasion/attrition intensity was observed with high values of the model parameters namely the restitution coefficient, static friction coefficient, and rolling friction coefficient.

By Kenneth McGowan

"The aluminum industry is the 5th largest consumer of energy and the largest consumer of energy on a per-weight basis. Process heating accounts for 25% of the energy consumed to manufacture aluminum. Consequently, the generation of this energy results in the production of a significant amount of CO2 (over 3.75 million metric tons in 2003)1. As a result, the Aluminum Industry Technology Roadmap of 2003 listed the development of improved refractory materials as a goal to reduce energy use and decrease greenhouse gas creation. The result of a R&D effort addressing this desire is the development of patented microporous refractory materials for metal contact applications in all furnace areas including the belly band. It has been demonstrated that this material can reduce energy consumption up to 38% in furnaces and significantly reduce heat loss in launder and trough systems. Furthermore the material developed is non-wetting and remains un-penetrated by metal throughout its lifetime. The material does not contribute to the formation of corundum. As a result, the energy efficiency of an older lining remains intact compared to standard refractory materials which may have an initial high insulating value (such as lightweights and board) or standard dense refractory (even with penetration inhibitors) both of which show a rapid increase in thermal conductivity as the refractory is penetrated with aluminum and formed corundumIntroductionThe aluminum industry is the second largest producer of metal in the United States, behind the iron and steel industry. It is the 5th largest consumer of energy and the largest consumer of energy on a per-weight basis. Process heating is required to melt, hold, purify, alloy, and heat treat the metal and accounts for 25% of the energy consumed to manufacture aluminum. As such, process heating is the second largest energy consuming operation. Smelting, which utilizes an electrolytic reduction process is the largest energy consuming operation1.Most process heating is accomplished through the use of fossil fuels, either directly or indirectly. The choice of fuel is dependent on a plant’s location and fossil fuel availability. Table I shows the processes impacted by refractories and the calculated BTU’s generated by usage of the respective fuels as well as the Metric Tons (MT) of metal passed through each process in 20001."

Jan 1, 2009

By John W. Thatcher

A demountable X-ray tube vacuum spectrograph was designed by the Bureau of Mines for the determination of long-wavelength X-ray spectra from the light elements. This instrument was operated for both secondary and combined primary-secondary excitation of the aluminum K-series. There was an increased analytical sensitivity for elements in period 3, and an indication that with improved X-ray tubes or direct election excitation of the sample, X-ray determination of elements in period 2 is also possible.

Jan 1, 1965

By Maral Malekian, Pat Bellett, Eranda Tennakoon, Fernanda Carrea, Moe Momayez

Slope instabilities in open-pit mines pose a safety risk to workers and a financial burden on production. The direct impact of slope stability on safety and production makes slope failure predictions one of the important challenges in the mining industry. Predicting the precise time of slope failure has been the subject of much research in conjunction with the development of innovative monitoring technology designed to prevent sudden failures. This paper investigates the use of AutoRegressive Integrated Moving Average (ARIMA) model to predict the time of slope failure. Input data such as inverse velocity (IV) and dimensionless inverse velocity (DIV) from 20 slope failures were used to train the model predict the failure time. For comparison purposes, the time of slope failure using the traditional inverse velocity method is also provided. We show that ARIMA provides 90% more accurate predictions than the TIV approach.

Jul 12, 2023

By M. A. Mahboob, T. Celik, B. Genc

Mineral Resources estimation plays a crucial role in the profitability of the future of mining operations. The conventional geostatistical methods used for grade estimation require expertise, understanding and knowledge of the spatial statistics, resource modelling, geology, mining engineering as well as clean validated data to build accurate block models. However, the geostatistical models are sensitive to changes in data and would have to be rebuilt on newly acquired data with different characteristics, which has proved to be a time-consuming process. Machine learning methods have in recent years been proposed as an alternative to the geostatistical methods to alleviate the problems these might suffer from in Mineral Resource estimation. In this paper, a systematic literature review of machine learning methods used in Mineral Resource estimation is presented. This has been conducted on such studies published during the period 1990 to 2019. The types, performances, and capabilities, of several machine learning methods have been evaluated and compared against each other, and against the conventional geostatistical methods. The results, based on 31 research studies, show that the machine learningbased methods have outperformed the conventional grade estimation modelling methods. The review also shows there is active research on applying machine learning to grade estimation from exploration through to exploitation. Further improvements can be expected if advanced machine learning techniques are to be used.

Nov 30, 2022

By Thomas O. Llewellyn

This U.S. Bureau of Mines (USBM) report presents a concise review on sources, processes, supply, and historical use patterns of domestic cadmium. It also covers a preliminary estimated cadmium material flow for the year 1989. This preliminary study contains information on cadmium and cadmium-bearing products in the United States. The data in this report were obtained from both published and/or unpublished sources of information. However, in order to estimate the fate of cadmium in each operation or application stage, some assumptions, judgments, and correlations were made by the USBM in an attempt to determine the material flows losses.

Jan 1, 1994

By Russell Barr

Operational excellence is generally known as a management system integrated across critical functions that is geared towards continually improving operational performance. Functional areas such as health, environment and safety, quality and human resources are the focus of many corporate-wide operational excellence programs. Operational excellence also focuses on improving areas such as customer orientation, employee empowerment as well as process, and systems optimization. It is widely viewed as critical to sustaining business performance improvement. Although it is difficult to find a universally accepted definition, or even common foundation in many respects, operational excellence remains a popular term in the business world. Many organizations have developed their own version of organization excellence, influenced by such individual factors, other similar institutions or even third-party service providers. A mining organization is no different from other organizations in that adopting and implementing effective operational excellence programs can dramatically improve business execution and performance across regional or global interests. This paper brings together various perspectives of operational excellence and reconciles them for a useful composite for the mining industry. While most agree that operational excellence should include normal functions in a manufacturing operation such as production, maintenance and engineering and processes such as quality, environmental and continuous improvement, many other factors for operational excellence seem to vary from perspective to perspective. Thus, programs that manufacturers engage in may seem the same, but may, in fact, be different in key areas. This may affect organizational performance in tangible ways. Management must buy into the company?s definition of operational excellence and be dedicated to achieving it. A review of many of the existing definitions of operational excellence, explicit or embedded as part of a program, seems to yield the following common factors: ? It should help organizations better execute their processes and services. ? It should be geared towards improving quality ? It requires that the various operations should be aligned with the overall enterprise strategy. ? It should be geared towards continuous improvement. A composite of operational excellence definitions suggest that it is: ? Geared towards helping the organization achieve sustained profitability; ? tied to strategic alignment and business objectives; ? tied to solid investment strategies; ? integrated as part of the culture, process, time plan and performance; ? a relevant performance measurement system; ? extended to include all aspects of the supply chain (including external suppliers); ? integrated with health, safety and environmental (HSE) aspects. And, while the pursuit of operational excellence intuitively suggests that businesses should improve, it is very difficult to achieve given the difficult challenges facing companies today. Mining businesses face numerous pressures to perform in a global marketplace such as demand, energy cost, variable cost and pricing fluctuations as well as infrastructure challenges to further confound the environment. Companies generally must look to the following:

Jan 1, 2009