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By N. J. Bolin

The Aitik copper mine is located in the north of Sweden and the concentrator at the mine started its operation in 1968 with a capacity of 2 Mton ore per year. Since then the operation has expanded several times, and today the capacity is 18 Mton ore per year. A new expansion plan was investigated in 2005, however the building of a new concentrator was found to be a better solution, giving a lower cost, a longer lifetime and more concentrates to the smelter at the coast. Several choices have been evaluated regarding the location of the concentrator?s crushing, grinding, dewatering, process control and water systems. The energy cost comparison has been an important factor when evaluating the various choices. The single most important decision has been in choosing the grinding system. Once again the fully autogenous grinding system, favoured by Boliden, has proven to be the best solution. The location of the mill, high and near the tailing pond, gives lower transportation costs for the ore and tailings, compared to other locations. A new water system will lower the pumping cost, give better control of water circulation to the plant and create fewer problems with permafrost in the tailings disposal area. Molybdenum recovery will be installed in the new plant using a separate circuit. A gold leaching plant was also investigated. Gold leaching is planned for the pyrite concentrate from the chalcopyrite/pyrite separation and the concentrate from the desulphurisation circuit that will be installed on the bulk flotation tailings.

Jan 1, 2014

By Fabiano Soares

Strand guide rolls in continuous casters are crucial components for guaranteeing an optimum process for the production of high-quality steel grades. The properties of these rolls greatly influence the quality of the slab produced. The most commonly used designs so far have been the axle roll and the solid roll. A quite new roll concept is the STEC-Roll®. It combines the advantages of the axle roll with those of the solid roll. This paper explains the development of this roll type and shows the current design. The characteristics of the STEC-Roll® are presented in greater detail and are underlined by a number of simulation results. Beside the design itself, the benefits for casting and maintenance are explained, including for example the easy assembly and dismantling or the use of the roll for dry casting. A brief examination is made of the TCO for the STEC-Roll® and an estimation is provided of the exchangeability of this roll. To conclude, an overview on the current applications is presented.

Aug 17, 2017

By John H. Schloen

Copper refineries are constantly looking for methods to upgrade their plants to reduce refining costs and to improve the purity of their electrolytic cathodes at the same time that the purity of the anodes they refine is being lowered by the rehabilitation of reverberatory furnace smelters to one of the direct smelting processes. The comments given below are based on the answers to the questionnaire returned bf the 36 copper refineries that represent 66% of the western world s refining capacity. Eleven refineries employ some form of uniform weight anade casting, e.g., Outokumpu, Contilanode, Mitsubishi, Lurgi, or Hazelett. This type of anode casting presents the best possibility for improving cathode purity. The cathode press of Phelps Dadge can improve current efficiencies and cathode quality. The press is used on first-run cathodes, after 48-60 hours, on half-cells at a time without interruption of the cell current. One refinery interrupts current for sever.al hours to allow the anode slime to settle before the, cathode pressing. The cathode press is now used at eight refineries. Apart from periodic reverse current (PRC), it is not expected that current densities will be increased. Thirty refineries, using direct current, average 231 amps/M, with a low of 178 and a high of 350. Five refineries use PRC at an average of 338 amps/M, with a low of 290 and a high of 380. Current efficiencies are good at an average of 94%, with a low of 88% and a high of 99% for the 34 refineries that reported. It must be remembered that the cycle efficiency with PRC is about 93%., so that the effective current efficiency with PRC would be only .94 X .93 or 87% However, PRC should be considered seriously for refinery expansions because it can save about 25% on capital costs.

Jan 1, 1987

By K D. Wilkes

The WEMCO Heavy Media Drum Separator was first introduced by WEMCO in California in the 1940`s, initially from their base in San Francisco and later when the company moved to Sacramento. The WEMCO Company became a part of EIMCO Process Equipment in 1985, and in 2002 EIMCO became a part of the GL&V Group when Dorr-Oliver EIMCO was created. Throughout this period of time the WEMCO Drum has been installed on a variety of different applications and is now operating at the heart of many of the world?s largest Minerals and Coal Processing Plants, as well as being used by many smaller producers and metal re-cycling operations. This paper looks at the practical aspects of using WEMCO Drums in a representative range of processing applications.

Jan 1, 2006

By Jim Bruce

No answer required. From the drilling equipment suppliers, but the specifications must be tailored to be project-specific. Yes, the sonic technique is very interesting as we said, and it is not so much as an issue of the magnitude of power, it's about the efficient use of the power. The efficiency of the machine is not necessarily related to size so it is best to talk to the two contractors that supply the service about that. I think it can be scaled down but it is quite a big head, so therefore there are practical limitations on the size of the door it can walk through and also the size of the casings and rods that it can use. You might defeat the economic advantages if you were to use too short casing lengths. Boart Longyear have a low head room machine that can work within an 8 foot verical clearance.

Feb 10, 2003

By F. L. Pirkle, W. C. Bagby

The International Mineral Valuation (IMVAL) Committee, founded in 2012, develops strategies for conducting mineral valuations. These strategies have been developed into a mineral asset valuation template called the International Mineral Property Valuation Standards Template and is part of IMVAL's work to establish consistent international standards for mineral property valuation and reporting. This template is a living document that is updated from time to time and is based on three core values or pillars (Fundamental Principles): Competence, Materiality, and Transparency. Objectivity, Independence, and Reasonableness may be applied as required by national codes or standards. The Template harmonizes international standards for valuation of mineral assets as real property and represents a consensus of current good practices. It is not a stand-alone reporting code and does not supersede existing national reporting standards. The Template deals with mineral-property valuation as distinct from mineral-project evaluation. INTRODUCTION In his 1989 book, “The New Realities”, Peter F. Drucker, Clark Professor of Social Science at Claremont Graduate School, California, stated: “Information is data endowed with relevance and purpose. Converting data into information thus requires knowledge. And knowledge, by definition, is specialized.” (p. 209) The discipline of mineral valuation is knowledge-based and requires a mineral valuer to collect, analyze, and interpret data that are material to a mineral valuation assignment. In so doing, the valuer turns the data into information (data come first, followed by information as determined by the mineral valuer) for use by the client (from whom the valuer obtained the mineral valuation assignment) and other intended users. The valuer uses his or her experience and education (each valuer’s knowledge base) supported by a foundation built upon competency, materiality, and transparency, the three pillars of mineral valuation (“minerals valuation”, “mineral-property valuation”). The International Mineral Valuation Standards Template (“IMVAL Template”, IMVAL”, “Template”), third edition dated May 2018, defines mineral valuation as: “The estimation of the Value of a Mineral Property in money or monetary equivalent. The word ‘valuation’ can be used to refer to the estimated value (the Valuation conclusion) or to refer to the preparation of the estimated Value (the act of valuing).” (p. 14) Furthermore, the IMVAL Template clearly separates valuation from evaluation: “The Template deals with Valuation, which is distinct from Evaluation. The distinction inherent in these defined terms is that Valuation addresses the estimation of value of a Mineral Property, whereas Evaluation addresses the broader assessment of a Mineral Property for an investment decision.” (p. 2)

Jan 1, 2019

By Xiaozhen Song, Ashish Ranjan Kumar, Shimin Liu

Diesel particulate matter (DPM) presents considerable occupational health hazards in large-opening underground mines (LOUM). Previous studies have primarily focused on single-factor ventilation optimization, while this study innovatively integrates booster fan configurations and loading truck placements utilizing a coupled CFD turbulence– particle tracing model. Three distinct ventilation scenarios were simulated to evaluate their effects on DPM dispersion and dilution efficiency. Results indicate that dual booster fans substantially enhance airflow distribution, increasing air exchange efficiency; The migration pathways of DPM closely align with airflow trajectories, and air turbulence is the predominant factor influencing particle behavior within LOUM; Loading truck placement critically influences local DPM accumulation; Airflow effectiveness diminishes markedly with distance from booster fans, causing stagnation at distant working faces. The coupled CFD approach accurately captured airflow–particle interactions, offering valuable insights for optimizing mine ventilation strategies and effectively mitigating miners’ exposure to DPM.

Feb 22, 2026

By I Minniakhmetov, J Ashford

Orebodies constitute naturally occurring, commonly highly variable concentrations of minerals in the earth’s crust formed through varying and highly unpredictable processes. Orebody knowledge is a core foundation of a mining company’s asset base underpinning all decisions about Mineral Resource and Ore Reserves, future production, development and ultimately the profitability and competitiveness of a mining enterprise. The decision to invest in a mineral project is usually based upon a techno-economic evaluation of the project and having clear approval pathways to gain local community support and address social and environmental impacts. The main objective of the techno-economic evaluation is to determine the optimum development sequence for the particular orebody in question and to estimate the economic viability of the project and the future return on investment to its stakeholders, balancing the inherent value of the mineral in the ground against the costs of development and market pricing. With the exception of market-driven commodity prices, virtually all revenue and cost estimates fundamentally stem from the understanding and subsequent modelling of the orebody. A reliable estimate of the ore deposit grade and other geological value-drivers is the foundation upon which the business case for future mine development and operation is intricately dependent. Orebody knowledge is, therefore, the fundamental driver of the mineral project cycle, influencing the progression of studies and consequently, the resource company’s ability to declare Exploration Results, Mineral Resources or Ore Reserves which govern the source and cost of funding available to the project. Drilling provides a ‘vector’ to the true nature of the orebody and effectively buys time to manage the technical risk associated with the orebody. Despite its perceived high cost, in both time and money terms, drilling is the only available technology for acquiring the necessary orebody knowledge to support technical and economic studies and to minimise orebody-driven cash flow uncertainty and volatility. However, like all costs, pressure to minimise drilling budgets is ubiquitous across the minerals industry. Paired with inappropriate key performance indicators, drilling is often regarded as a cost to be minimised, rather than an investment to be optimised. Furthermore, as future deposits get deeper and more complex, the collection of orebody knowledge is increasingly on the critical path for project development. The increasing cost of data collection pertaining to these deposits increases the temptation to minimise orebody knowledge gathering at the cost of long-term value as the reduction or postponement of drilling results in greater orebody knowledge risk at all stages of the value chain. Indeed the true cost of the decision to drill less is rarely known until the mine is in operation, well after the mine project evaluation team has moved on. This paper aims to promote orebody knowledge as the fundamental source of endogenous project financial risk and, consequently, its critical importance in project financial evaluation. Furthermore, the report documents experimental research into the development of an econometric model for valuing orebody knowledge. Using the density of drilling data as a proxy measure of orebody knowledge, the proposed approach integrates well-established stochastic grade modelling techniques with the mathematical mechanics of Decoupled Net Present Value (DNPV) which, combined with stochastic grade modelling (conditional simulation), lends itself to the financial International Mining Geology Conference 2022 | Brisbane, Australia and Online | 22–23 March 2022 3 assessment of orebody knowledge risk. Based on this approach, a metric is formulated, representing the minimum value of the orebody knowledge added by additional drilling

Mar 22, 2022

By S T. L Harrison, J-P Franzidis, M Becker, N Dyantyi, J L. Broadhurst

Gold mining is a major contributor to the South African economy, but is associated with several environmental issues such as acid rock drainage (ARD). ARD is due to the oxidation of sulfides in gold tailings and is characterised by low pH, high sulfate content and elevated concentrations of heavy metals that contaminates scarce water resources and subsequently limits the use of such waters without treatment. Treatment strategies can only be implemented if the acid-generating potential of mine wastes is effectively predicted using common static and kinetic acid prediction tests. The choice of test performed is usually a trade-off between the number of samples, speed of the test, cost of the analysis and level of information obtained. Often the results of these various tests are not consistent with one another. This study uses mineralogy to analyse biokinetic test results of a Witwatersrand gold sample in order to improve the understanding of behaviour of mine wastes under different ARD prediction test conditions.All ARD prediction testing methods investigated in this study showed that the gold sample is considered to be potentially acid forming with net acid generation (NAG) pH of 2.5 and net acid producing potential (NAPP) of 36 kg H2SO4/t. Results of biokinetic test showed that ANC was consumed within four days confirming acid producing potential of the sample with low neutralising potential as observed from acid base accounting (ABA) (4.7 kg H2SO4/t) and mineralogy (4.9 kg H2SO4/t). Results generated in this study demonstrated importance of mineralogy in both understanding the controlling reaction mechanisms playing key role in ARD formation and its capability as a prediction technique. Future work will focus on the application of mineralogy in interpreting the behaviour of mine waste under different static test conditions with a view to assessing their applicability and reliability in estimating potential acid generating characteristics of gold tailings.CITATION:Dyantyi, N, Becker, M, Broadhurst, J L, Harrison, S T L and Franzidis, J-P, 2013. Use of mineralogy to interpret laboratory-scale acid rock drainage prediction tests - a gold case study, in Proceedings World Gold 2013, pp 519-526 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Tegner C. Johnson

Just a few years ago, my company was referred to as the Marion Steam Shovel Company. Though we still make shovels, both two and eight-crawler types, the eight-crawler stripping shovel appears to have been replaced by the walking dragline for overburden removal and in some cases for the mineral as well. The walking dragline appeared in the coal fields in the early 1930's. It is popular because it can cope with overburden depths in excess of 100 ft and with blasted sedimentary rock, all at an O & O (ownership and operational) cost of ±10[c] per bank cu yd (bcy).

Jan 10, 1974

By Håkan Tyni, Jan Björkman, Per-Olaf Samskog, Irving Wigdén

Process automation can provide better utilization of capital investments. Furthermore, it is a necessity for securing the high demands of product quality. In this paper, process automation in underground mining as well as in the beneficiation plant will be discussed. The development of reliable broadband communication systems for real-time transfer of image, audio and data have enabled remotely controlled LHDs and drilling rigs. In the beneficiation plants, model-based expert control systems far on-line dynamic process optimization and control have been installed in unit operations such as grinding, flotation and induration.

Jan 1, 2000

By R. L. Beatty

IN INDUSTRIAL and domestic daily life carbon monoxide is the most frequently encountered toxic gas. hazardous concentrations of carbon monoxide may be present in the vicinity of many industrial operations, such as metallurgical processes, coke ovens, and fuel- and synthesis-gas producers, and may be encountered in confined spaces, such as dwellings, garages, workshops, vehicular tunnels, and mining operations, in connection with the use of heaters, boilers, internal-combustion engines, after blasting operations, and after fires and explosions. Evaluation and control of the health and safety hazard caused by carbon monoxide depend primarily on the analytical detection of the presence of carbon monoxide and determination of its concentration in air and in various gaseous mixtures. The choice of method of analysis in any particular situation depends on such factors as required accuracy, range of concentration involved, convenience, speed of analysis required, quantity of sample available, qualitative composition of sample or atmosphere to be analyzed, and possible effects of interfering gases. Some of the methods described require only adequate understanding of operational techniques, whereas others require thorough appreciation and skill in applying the principles involved. The instruments and analytical procedures commonly used for detecting and determining carbon monoxide are described in detail, and reference is made to more specialized methods:

Jan 1, 1955

By F. C. Harris, S. J. Gaab, J. Sattarvand, S. Duzgun

Underground mines are inherently dangerous due to potential hazards such as fires, explosions, and caving of rock. Although these events are rare, once they occur a speedy and safe egress of mineworkers is critical to survival. Static evacuation systems use exit signs or directional lines but can get obstructed or be hardly visible in smoky or dusty conditions. This paper presents the investigation of the effectiveness of a smart evacuation technology in underground mining, where a real-time guidance system leads individuals on an optimised path to the egress while avoiding danger zones, compared to conventional practices. Participants simulated an evacuation from a virtual reality mine, using the conventional system and the smart evacuation system with real-time guidance. The highest reduction in evacuation time using the smart method amounted to nearly 40% on average. Moreover, 83% of participants preferred the smart guidance system, and agreed that it could enhance safety.

Sep 1, 2021

By J. Mackintosh Bell

External trade strongly influences the well being of all nations. In the modern economic mechanism, no country is so well endowed that it has not to import commodities from others and to export its products in turn to make good its deficiencies, to rectify or improve its financial structure. From the standpoint of international commerce, Canada is strategically well placed. On the south she is bounded by the richest country in the world. On the east she faces the Atlantic, on the west the Pacific. On both coasts there are fine harbours to which lead great lines of railway that span the continent. Canada is now fifth among the exporting nations of the world. For disposal abroad, she has enormous quantities of primary commodities and substantial amounts of manufactured goods as well. But she is far from being self-sustaining. She is unusually dependent on foreign trade, not only because of the commodities she has to sell but because of the lack of many essential articles she does not or cannot produce. To Canada, external commerce is vastly more important than internal trade. The wealth of nations is decided by their ability to produce more than they need, to sell more than they buy, and to build up favourable balances resulting from trade or services. With few countries, however, are returns perennially satisfactory. Fruitful periods are followed by leaner years. In times of prosperity foreign credits are increased, monetary systems strengthened, reserves accumulated to withstand recurring days of strain. Today, the foundations of financial systems are being re-examined, "dogmas hitherto accepted as canonical are being questioned" . It is not only in Europe and America that men search for illumination in problems arising from monetary restrictions.

Jan 1, 1933

By C. T. Anderson

In July 1947, the U. S. Bureau of Mines, in cooperation with the Air Materiel Command, started an investigation of zirconium alloys with the object of determining the suitability of such alloys for high-temperature applications. This report covers the preliminary study of about 25 zirconium-rich alloy systems with respect to preparation, fabrication, tensile properties, metallographic structures; constitution, and heat resistance. Obviously, each system could not be investigated thoroughly, and this publication can be regarded only as a first approach. The more promising individual alloy systems will be studied in greater detail and reported in subsequent publications. The study of zirconium alloys on such a scale has been made possible by the U.S. Bureau of Mines developments in the past 5 years On producing zirconium metal. This basic process is similar to that developed by Kroll for producing ductile titanium metal and consists essentially of reducing zirconium chloride by means of molten magnesium. The Northwest Electrodevelopment Laboratory at Albany, Oreg., has produced several thousand pounds of ductile metal in this manner and has a pilot plant producing over 300 pounds of metal per week. Alloys were prepared by melting Bureau of Mines zirconium and the best available grade of alloying element in graphite, with suitable provisions for preventing oxidation. The ingots were quartered longitudinally and sheath-swaged at 850° c. to 3/8-inch diameter rod. Two of those rods were send to Wright Field for room-temperature and 1,200° F. tensile properties. The remaining two sections were used for metallographic, hardness, heat-treatment, and heat-resistance studies. The salient features of this investigation are summarized in table 1.

Jan 1, 1950

By R. Hurman Eric

The dew-point technique of activity measurements take advantage of the volatility of a component in solution. The pressure of the volatile component over a sample is determined from observations of the temperature at which condensation of the vapor occurs. The method is applicable best when the vapor pressure of the components would differ by about two to three orders of magnitude. Experimentally, this is a closed system involving the use of evacuated and sealed transparent quartz sample probes. Furthermore reliable vapor pressure data of the volatile component is essential along with a specialized high temperature furnace capable of giving reproducible results. In this context, the vertical Dew-Point Furnace (DPF) was designed and built after elaborate trails until enough proficiency was gained for reprodueible results. Over the years the DPF was modified and improved. The DPF developed was versatile and could easily be used for activity measurements in the isopiestic mode (another method of measuring activities of a volatile component in a solution). The necessary ancillary systems; namely evacuation-flushing-evacuation followed by sealing of quartz sample probes under vacuum were also perfected over the years. As and when necessary the dew-point technique was supplemented by classical equilibration-quenching method employed on the sealed quartz sample probes to reveal necessary phase equilibrium information. The following were studied utilizing the above technique: (i) Activities in CuzS-PbS and FeS-PbS binaries and CU2S-FeS- PbS ternary at 1200°C; (ii) Activities in CuzS-SnS and FeS-SnS binaries and Cu2S-FeS-SnS ternary at 1200°C; (iii) Phase equilibria and thennodynamic in Cu-Pb-S, Fe-Pb-S, Fe-Sn-S, Cu-Sn-S and Ag-Sn-S systems. Most recently the following systems have been tackled: (i) Phase equilibria and thennodynamics in the Ag-Pb-S and Sn-Pb-S systems; and (ii) Activities in Ag2S-FeS-CuzS-PbS quaternary at 1200°C.

Jan 1, 2003

By P Hanna

Following the Busang fiasco, more detailed guidelines were appended to the latest revision of the JORC Code released in September 1999 (JORC, 1999). Although the definitions and terminology essentially remained unchanged, the additional information in the guidelines has highlighted a number of issues for consideration by geologists undertaking computer-based resource estimations. The three main issues are:Data Integrity û details such as drilling and logging techniques, sampling procedures, assay tests, site visits, data recording and aggregation methods need to be considered. Geological Interpretation û is the Competent Person applying the appropriate software interpretation to the deposit in accordance with the regional setting. Are the correct computer-based tools being applied and are they producing the desired result (without compromise) to the satisfaction of the Competent Person? Modelling Technique û the importance of the relevant experience of the Competent Person not only in regard to the geology, but also with respect to the modelling algorithms and resource calculation methods of the computer software system involved. At the end of the day, it is essential that the Competent Person undertake a reality check on the resource estimation itself. They should also check that the borehole spacing is in accordance with the level of continuity for each critical parameter (such as structure, grade, impurities, etc) for which the resources are categorised.

Jan 1, 2000

By Brian J. Olson, Kevin Haiar

Originally constructed between 1939 and 1941 as part of Franklin D. Roosevelt’s New Deal programs, the Bonneville to Hood River 115 kV Transmission Line required an infrastructure upgrade to remain reliable and in-service. The line traverses the rugged landscape of the Columbia River Gorge on the Oregon- Washington border, featuring steep, talus slopes; uneven, rocky terrain; and a variety of environmental sensitivities. This paper details the design and construction of 27 micropile foundations for new, fire- hardening steel poles through a particularly challenging stretch of the alignment. The difficult access and environmental constraints at these sites designated them as helicopter-accessible and precluded the collection of detailed geotechnical information prior to construction. Micropiles provided a viable foundation alternative due to their portability and flexibility during construction. Detail will be provided on the extensive preliminary desktop study performed, as well as the process of developing engineering designs to successfully accommodate for variability and unknowns in complex geological conditions. With an increasing number of electric power projects traversing challenging terrain and facing similar obstacles, this project stands to provide valuable lessons learned to the industry.

Sep 8, 2021

By M. J. Beus

Technology to enhance safety during mine hoisting has been developed by researchers at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health. Assessment of current hoisting technology suggests that monitoring conveyance position and load directly from the skip or cage top offers several significant safety advantages. Wireless data transmission schemes and a package consisting of sensors, batteries, and a charger mounted on the wire rope and skip have been developed. A state-of-the-art automated hoisting test facility was constructed to test the concept in a controlled laboratory setting. Field tests in a full-size shaft are underway.

Jan 1, 1999

By A J. Gunson

The Norman B Keevil Institute of Mining Engineering, or the Department of Mining Engineering (the Department), at CanadaÆs University of British Columbia (UBC) is addressing the integration of sustainable development concepts into mining education and research on behalf of industry and society. Over the past decade, the DepartmentÆs education and research model has been evolving to incorporate collaborative and multidisciplinary strategies, where sustainability initiatives are taught in classes, supported in research and discussed in a voluntary collective of mostly graduate students û the Sustainability Working Group (SWG). The SWG has brought together a diverse array of disciplines from academia, industry, government, non-governmental organisations (NGOs) and mining communities. The operational mechanisms and structure of the SWG have enabled momentum to be gained through several multidisciplinary educational and research networking initiatives. It acts to attract new students with diverse backgrounds, foster innovative research, develop relationships and networks, and create the space to discuss progressive ideas and projects. The original cohort of SWG graduate students laid the foundation for sustainable research initiatives within the Department at UBC. Novel research has incorporated topics such as: community resilience, artisanal small-scale mining, sustainability indicators and corporate social responsibility, environmental assessment and impact benefit agreements and the recycling of waste. Propelled by the support of the Department and inspired by the works completed, a host of new graduate students have embarked on their research quests to integrate sustainability principles into their projects. Such projects include: social impacts and benefits of mining, artisanal small-scale mining, community health, the production and transport of mine pollutants, mine waste management, mineral process plant design and the evolution of community education and mine policy. This paper reports on the departmentÆs continuing research and development towards an understanding and evaluations of the ongoing contributions of mining to sustainable development.

Jan 1, 2009