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By Bird. M.

As the Cadia mill was the first 40ft diameter SAG mill, commissioned in 1998, its performance, liner and discharge design attracted considerable international attention. Twelve years on, the liner design and the control philosophy are being readdressed to further improve the mill?s performance. A comprehensive series of 3D liner scans, over life of the liner, have been used to calibrate liner mass loss and progressive changes in the liner profile. This data is being used to provide true charge mass and mill filling, plus progressive trajectory profiles over life of liner. This information, along with measures of mill performance over liner life, is being used to select the optimal operating conditions as the liner wears, and hopes to inform future liner design.

Jan 1, 2012

By Bearman R. A, Parkin R. M

In the comminution industry cone crushers are widely used for secondary and subsequent stages of size reduction. Traditionally cone crushers have been operated and monitored manually. Alteration of discharge setting is now commonly achieved via hydraulic means, however, compensation of liner wear can still involve plant shutdown and loss of production. Drift in discharge setting due to liner wear is still a major problem that must be addressed to improve product quality, consistency and reduce recirculating load. The continuous demand for better quality products and the high cost of reprocessing or discarding unsaleable material, highlights the need for re-examination of the technology associated with the crushers to ensure optimum control and system efficiency. A collaborative project between Pegson Ltd, one of the leading UK manufacturers of jaw and cone crushers, De Montfort University Leicester, and Transfer Technology plc was established to address the technological requirement for automation of the control of cone crushers. The machine chosen for the study is a 900 Autocone cone crusher manufactured by Pegson Ltd. The design philosophy is based on a mechatronic approach providing a complete solution through a distributed network of intelligent sensors, artificial intelligence technology and adaptive control. The modular design of the system ensures a progressive sophistication in technology that allows the automation to be phased in as required. This will ensure maximum benefits to all sectors of the aggregate industry. It is estimated that the automation will result in savings of around ten per cent. The savings will result from minimising the production of unsaleable products by reliable condition monitoring and automation of the control and maintenance of system parameters to optimise system efficiency. Extension of the methods and principles into the mining sector is anticipated. The control over the size of crusher product will offer great benefits to the mining industry with significant implications for subsequent milling and beneficiation processes.

Jan 1, 1995

By Kalyani Devabhaktuni, Mike Minton, Mark T. Howe, Yan Zhang

During the procurement phase of a Design-Build (DB) project, design-build contractors must often commit to a fixed price based on limited or incomplete geotechnical information. This lack of information can result in an inaccurate assessment and allocation of project risk to either the contracting authority or the DB contractor. This paper presents a case study of an elevated water tank supported by mixed ground improvement techniques, including Vibro-Compaction (VC), Aggregate Piers (AP) and Compaction Grouting (CG) in East St. Louis, Illinois. An adaptive design and contracting approach provided the best value solution for a complicated set of geotechnical problems, including static bearing capacity and settlement concerns as well as liquefaction induced settlement. Close cooperation between the owner, the tank contractor, the geotechnical engineer and the ground improvement contractor was essential to produce an effective solution. Ground Improvement techniques resolved the geotechnical challenges at the site through adaptive design methods, utilizing progressive rounds of verification and real time data acquisition to achieve performance objectives. This paper details the evaluation of geotechnical criteria, the selection of ground improvement techniques, the adaptive design and implementation of ground improvements, as well as contracting methodologies used to ensure that the best value was provided. PROJECT INFORMATION In November, 2016, CB&I Storage Tank Solutions (McDermott) submitted a design/build proposal for an elevated water tank for Illinois American Water Company (IAW) in East St. Louis, Illinois. The purpose of this tank was to have backup water capacity for power generation. In the RFP, IAW requested two alternate styles of tank: Option 1, a 1250 Million Gallon (MG) Composite Elevated Tank or Option 2, a 1250 MG Waterspheroid tank. Option 1 consisted of a steel tank supported on a concrete tower. Option 2 consisted of a steel tank supported on a steel shaft. The height (determined by IAW) was 140 feet to the top capacity line measured from top of floor slab.

Jan 1, 2019

By R L. Grogan

Regulators of deep-sea mining projects are becoming increasingly hesitant about the concept of adaptive management as a tool to facilitate compliance and continuous improvement. Adaptive management is a relevant and useful instrument to ensure that the mine plan is successfully implemented throughout the life of mine, in parallel with optimum environmental performance and compliance.CITATION:Grogan, R L, 2018. Adaptive management in deep sea mining – looking like you know what you’re doing when it’s never been done before, in Proceedings Life-of-Mine 2018, pp 20–22 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By Steven B. Van Kouteren

Added value is a term loosely used in the industry, but what exactly does it mean? What does it take to make a value-added product and more importantly how does a company maintain the value added to its products? Most people agree that value-added means the value of a mineral minus the cost to produce it. But what is misleading is that producing value added products does not necessarily guarantee the profitability of the products. In some cases firms that make "value-added" products are not very profitable. It is not only important to understand how to make a value-added product but also how competitive forces in the market can erode the value added. Therefore, when we look at value-added opportunities, we must understand how to obtain the value added and more importantly how to maintain the value. There are four major factors that limit a company's ability to add value to its products. This paper will examine these factors and will use the ground calcium carbonate and mica industries as examples.

Jan 1, 1990

By The Staff

This is in direct contradiction to the generally accepted philosophy of tube-mill grinding, which is based upon an enormous amount of experiment carried on in different parts of the world. Personally, I have no faith in the reliability of these conclusions of the authors. (Incidentally, the two circuits compared consist of six mills each of which the change in the hook-up is only in the last three mills-in one case, these three mills are in closed circuit and in the other, open or series circuit. Hence the last three mills are alone responsible for the alleged improvement, which means that the improvement in these three mills amounts to at least 18.8 per cent). The value of these figures depends upon the reliability of the work, of the measurements and the calculations of the authors. As very little information is contained in this Addendum concerning the methods of the work and the details of the measurements, it is necessary, in order to form an estimate of this reliability, to study carefully the previous paper published in the July, 1940, BULLETIN(3). Referring to the original paper, the present paper has this to say (bottom of page 379): "Here it may be remarked that we have made more money for Lake Shore digging into and forming the report than in obtaining the figures and data, and so far have never gone back to work on it without a resulting Lake Shore profit". Let me state that I, so far, have never gone back to work on it without finding more discrepancies and inconsistencies and illogical reasoning. In my first contribution to the discussion of the first paper, which discussion was published on page 355 and following, in the July, 1941, BULLETIN, I pointed out discrepancies and inconsistencies and illogical reasoning.

Jan 1, 1942

By R Schiller, E Chait

"Quebrada Blanca is a porphyry copper deposit located in the Eocene-Oligocene belt of Chilean Andes. Operation started in 1994 and original reserves for supergene mineralisation gave a life-of-mine (LOM) of 20 years; however, further exploration extended the LOM until 2020.In order to optimise the remaining five years of supergene resource, geometallurgical variables were added to the geological model including copper recovery and acid consumption. LOM plan encompasses finishing the phase number eight and the future development of phases 11 and 13.LOM lithologies include diorites, quartz monzonites, porphyries, igneous and tourmaline breccias. Main alterations are: potassic, phyllic and argillic. Litho-alterations or geometallurgical units were formed by combining five types of rocks with three types of alteration. According to statistical information, the deposit can be represented with 12 litho-alteration units, which cover 98 per cent of the LOM volume.For copper recovery information, there were 40 mini-columns tests made in order to obtain kinetics curves and copper recovery values after comparing the difference between head and tails grades. Acid consumption was obtained using an automatic neutraliser device-based test.Historical data said that copper recovery in pads after 450 days of irrigation is around 75 per cent of recoverable copper while acid consumption is around 5.5 kg/t.According to this study, lower recoveries are related with potassic-altered diorites and argillic-altered quartz monzonites with values around 60 per cent. On the other hand, best recoveries could be found in potassic-altered quartz monzonites and argillic-altered diorites with values closer to 80 per cent.It was also revealed that the most reactive rock is the potassic-altered diorite with 12 kg/t of acid consumption. This rock covers approximately 40 per cent from phases 11 and 13.The final geomet model was calculated using a program that relates each geometallurgical unit with a specific copper recovery and acid consumption value. Results found after comparing model-obtained information with historical leached pads data were used to validate the model.CITATION:Chait, E and Schiller, R, 2016. Adding Copper Recovery and Acid Consumption Variables to the Geological Model of Quebrada Blanca, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 257–266 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

In this paper, three types of value-adding in the minerals industry are discussed: downstream processing, improving the efficiency of existing processing and increasing the knowledge base and expertise of the staff. It is shown that, while downstream processing seems to offer a good way of improving Australia's trade position, there are a number of impediments to such development, notably, limited access to the appropriate technology and overseas markets. Transport costs can also be a problem. To reverse the situation will require more positive policies by government. In the meantime, something can be done towards adding value by increasing the efficiency of existing processes. Examples are given, showing how it might be possible to make economies in reagent costs in the gold industry, how innovative technology has led to more complete processing of a tailings dump, how research might lead to an increase in the throughput in the production of synthetic rutile and how it is possible to leach selectively from gold/copper ores.

Jan 1, 1995

By John Hinton

Electromagnetic based (EM) sensor technology has been shown to detect changes in the magnetic permeability of steel strip travelling down the run out table after rolling. Measuring below the Curie temperature, these changes can be interpreted in terms of the phase transformation from austenite (paramagnetic) to ferrite (ferromagnetic). These real time measurements provide a detailed insight into the changes in the structure at high temperature providing the steel producer with feedback on quality control, product consistency and product development. However unlike mill microstructure models, the sensor measurement provides a point reading at a distance through the cooling course. To map the transformation in more detail, a sensor array is required along the length of the Run Out Table i.e. to measure points on the austenite to ferrite transformation curve. This paper describes the process and metallurgical factors that should be considered in the optimum design of a sensor array, i.e. the number and location of the sensor heads. Examples of cooling strategies for different steel grades e.g. low carbon, structural and dual phase steels are used to demonstrate the importance of sensor location. In addition, the effect of variability within typical industrial parameters e.g. cooling speed, on the sensitivity of sensor output and location will be considered.

Oct 1, 2019

By Beatryz Mendes, Leonardo Pedroti, Afonso Azevedo, José Maria Carvalho

The dregs is a waste from the cellulose production, and its reuse is an effective way to reduce environmental impacts. Researches have already been done to incorporate it into building materials. The present work aimed at incorporating dregs in the production of mortar to replace hydrated lime. The methodology adopted was the Simplex network with ten sampling points, varying the amount of cement, sand, and dregs. Each mix was submitted to flexural strength, compressive strength, apparent mass density and water absorption by capillarity tests. The results were analyzed by the software Minitab, obtaining the influence of each component in the mixture. The best results were observed in mixes with a higher proportion of cement and less of residue when it was analyzed the flexural and compressive strengths. Larger rates of apparent mass density and water absorption were noticed with a greater amount of dregs. The experimental design also allowed the obtainment of mixture ratios from predetermined values of the tested properties and indicated that the addition of dregs in mortar could be an alternative to civil construction.

Mar 1, 2018

By I. Caraconcea, M. Cousineau, S. Gariepy

"Several base metal plants operate in low grade/high tonnage conditions which impose strict cost control on all fronts for their operations to remain profitable. This leads to decisions regarding plant design, procurement, operations and maintenance that often favor cost minimization over value optimization. This may hinder the representativeness of the metal accounting systems while this should be a priority in a low margin environment. Such poor representativeness not only creates confusion in plant scheduling but can also hide suboptimal metallurgical performance. Furthermore, this situation can run undetected for a while since one dominant feature of a poor metal accounting system is its poor self-awareness. During their practice, authors have particularly identified measurement bias and reproducibility, as well as their impact on metal recoveries as areas of concern. These issues have not been extensively reviewed in the specific context of precious metals in base metal plants. Pragmatic solutions are proposed either at the design stage for a new project or to retrofit an actual operation. These solutions should be based on a business analysis that set a value of information matching the contribution of precious metals as well as the potential to use such information to act toward increasing plant profitability. Conclusions are that trade-offs are an inherent part of the design/audit/retrofit of any metal accounting system in any plant processing either base or precious metals. However, compromises must be evaluated on economic/technical ground.INTRODUCTION Every mineral processing plant must produce metal accounting reports (Morrison, 2008) where estimated saleable metal flows and inventories are published. These metal accounting reports are delivered to a variety of stakeholders who use them for internal management purposes (day-to-day plant production planning, plant operation optimization, capital spending, etc.) as well as for external management (royalty settlements, tolling agreements, etc.). Hence, there should be no doubt that state of the art metal accounting is instrumental for mining companies to reach and sustain high-quality corporate governance (Gaylard, Randolph, & Wortley, 2014). However, producing a metal accounting report involves much more than just printing it (Lachance, Leroux, & Gariépy, 2015a). The underlying metal accounting system (Figure 1) is responsible not only for the reliable production of the metal accounting reports but also for the quality of the outcome. As such, the crucial tasks of its design/audit/retrofit should neither be seen as ancillary nor be left as an afterthought."

Jan 1, 2017

Many operating hard-rock sulfide mines are predicted to require perpetual post-closure management to prevent environmental degradation. Causes include evaporative concentration of metals and other solutes in pit lakes, and acid rock drainage from sulfide waste-rock, tailings, and pit benches. Dilemmas posed by the prospect of perpetual management include: uncertainty in predictive models typically prevents reliable bounding on forecasts for the timing or magnitude of environmental impacts; comprehensive closure designs that can meet environmental standards may not be economically possible, particularly when applied retroactively to mines permitted under less stringent closure requirements; the publication of site-specific environmental analyses in peer-reviewed journals are discouraged in the current regulatory environment, hindering scientific advancement; and the durability of financial and government institutions cannot be assured for the long-time horizons over which mine impacts are predicted to occur. Re-evaluating mine closure in a framework of sustainable development (as proposed by the Mining Mineral Sustainable Development forum), can resolve, in part, these dilemmas. Key sustainability goals include: assurance of the social and economic well-being of the local community; assurance of the long-term environmental integrity of the region; and establishment of institutions capable of addressing (and learning from) long-term environmental management. Under a sustainability framework, impractical plans for immediate attainment of perpetually-stable closure may be replaced with a fund for long-term management of environmental impacts (eg through contaminant migration controls and exposure barriers), and a set-aside long-term growth reserve intended to eventually fund more complete closure. Fund expenditures would follow Adaptive Managementùa template for environmental-management institutions in which knowledge accumulated and uncertainty acknowledged explicitly. Under adaptive management, trusts would be flexible entities, supporting an evolving program of monitoring, predictive model refinement, and treatment. Periodic value of information analyses would target data collection efforts, refining the balance between predictable cost and uncertainty. This framework could overcome present-day financial shortcomings, enhance the field of environmental science, and meet the needs of future generations through the propagation of capita.

Jan 1, 2003

By Shiqiang (Rob) Hui, Jiaren (Jimmy) Jiang, Rees Llewellyn, Yongsong Xie

Wear has been estimated to cost the Canadian mining/mineral processing industry over $15 billion per year mainly for repair/replacement of worn parts in 2013. The associated production loss is difficult to quantify but add considerably to the problem. The Canadian oil sands sector which has to deal with extremely abrasive and erosive solids, has traditionally incurred extremely severe and often unique attack. Demonstrable progress in mitigating the wear problems has been achieved through materials development, more informed materials selections, and better component and operation condition designs. An integral contributor to these advances is a long-term collaborative research partnership between NRC and the mining/supply industry. In this paper, this continuing collaboration will be described. A main focus is to identify degradation mechanisms occurring in the most severe and important service applications and to correlate these findings with laboratory test data. Relevant abrasion and erosion (often combined with corrosion) properties have been established and correlated with composition and microstructures for all classes of resistant materials ranging from relatively soft elastomers to ultra-hard ceramics. A comprehensive wear properties database has been compiled. This capability has been instrumental in facilitating the development of improved materials, optimizing materials fitness/selection for service, wear failure analysis, and quality assurance.

Jan 1, 2015

By A. K. Watt

"The availability of fresh water to meet present and future needs in Ontario is of concern to an increasing number of people. Rain and snow are the source of our potable water and provide, on the average, some 180,-000 billion gallons of water annually. This amount is reduced to 94 billion gallons a day as a result of the evaporation and transpiration of water and our inability to construct the necessary reservoirs for capturing surplus stream flow.The water used for domestic, irrigation, public supply and industrial purposes amounts to some 7 billion gallons daily at present and will reach 21 billion gallons daily by the year 2000; however, only about one-fifth of the water used is actually consumed, and this, along with the possibilities of water re-use, improves the water supply picture still further.The need for adequate pollution control has accompanied industrial and urban expansion and is an important factor in the extent to which our surplus water is used. In the 10-year period since the formation of the Ontario Water Resources Commission, the cost of water and sewage works constructed in the Province has exceeded one billion dollars. A special effort is now being made to control the industrial pollution situation.Numerous federal and provincial agencies are engaged in hydrologie studies in the Province, providing in-formation of benefit to those involved with water resources management."

Jan 1, 1967

By Enzo Palumbo, Joël P. T. Kapusta, François Larouche

In light of the rapid deployment of bottom blowing smelting in China over the last ten years, one has to wonder why it has taken the copper industry so long to adopt ultra-high oxygen enrichment via Savard-Lee type injectors. As early as 1976, Kellogg and Henderson suggested, in their landmark paper on energy usage in the copper industry, that ‘maximum use of oxygen enrichment of process air’ was one of seven ‘energy saving features’ for copper matte smelting and converting. Yet today, shrouded injection and high oxygen enrichment has not been implemented in copper bath smelting outside China and Vietnam. In this paper, the authors explore the reasons why bath smelting processes such as the Noranda Reactor and the Teniente Converter still operate around 40% oxygen enrichment, while the bottom blowing SKS/BBS process typically runs at 65 to 75% oxygen, with all three processes producing white metal. Are there fundamental metallurgical explanations for this striking difference beyond the long-standing skepticism towards high oxygen shrouded injection and its perceived high implementation cost?

Jan 1, 2015

By N. Vorob?ev-Desyatovskii

The process of gold(I) adsorption on activated carbon (AC) from aqueous Na[Au(CN)2] and the state of the adsorbed gold cyanide complex on the adsorbent surface was investigated by photometry, XPS, XANES methods. By DFT method, quantum-chemical calculations were performed of the gold cyanide species on activated carbon surface. It was established that the binding of gold(I) with the surface of carbon involved several simultaneous processes governing the selective adsorption of gold(I) from the cyanide solutions.

Sep 1, 2012

By A. Pomianowski

A spectrophotometric study of xanthate solutions alone and their mixtures with equimolar amounts of alkyl trimethyl ammonium bromide (CnTAB) has established the additivity of ultraviolet spectra (190 - 400 my) for potassium ethyl xanthate (KEtX) and C12TAB. No obvious effect of C12TAB addition on the decomposition rate of KEtX was observed. The kinetics of collector abstraction by copper, nickel and sphalerite powders were studied in 10-5 - 10-3M solutions of KEtX alone and in equimolar mixtures of KEtX and C12TAB. Presence of C12TAB caused a 2 - 3 fold increase in the amounts of xanthate (equivalent to many monolayers) abstracted by copper and, nickel powders but had no effect on the abstraction of xanthate by unactivated sphalerite. The adsorption of C12TAB itself from the mixed solutions was very low, at most ore monolayer only, and was not influenced by the nature of the solid powder used. The results are interpreted in terms of molecular associations and synergistic action of xanthates and quaternary amines.

Jan 1, 1963

By Dr. Anurag Agrawal, Fathur Rozaq, Nella Lubis, Relinda Sanistya, Herry Saputra, Rudolf Sitorus

In mining operations, basic drone applications such as pre- and post-blast photo comparisons, blast video recordings, and sample-based fragmentation analysis are often used to assess blast performance. However, these methods lack the depth needed for comprehensive evaluations, leading to suboptimal results. This study explores the innovative integration of drone mapping technology with artificial intelligence (AI) at the Martabe Gold Mine in North Sumatra Province, Indonesia, to address these limitations. High-resolution drones and ground control points (GCPs) are utilized to create detailed orthomosaic maps, and advanced AI algorithms are applied to enhance the accuracy of blast performance insights. Field experiments reveal substantial improvements in comprehensive blast performance evaluations through this integrated approach. Enhancements include improved pre- and post-blast evaluations, AI collar detection, fragmentation size measurements, heave muckpile profiles, cast material measurements, floor prediction models, and muck pile topography volume, which is vital for ore tonnage predictions. Notably, this method achieves an average volume accuracy of 1% compared to light detection and ranging (LiDAR) technology. While LiDAR is known for its precision, the drone-based method offers a highly accurate, cost-effective, and user-friendly alternative suitable for mining applications. Despite LiDAR's superior precision, our approach provides a practical solution due to its accessibility and ease of implementation. In conclusion, the integration of advanced drone mapping and AI technologies has the potential to revolutionize blasting operations. By addressing the limitations of previous methods, this approach meets the evolving needs of the mining industry and sets new standards for accuracy and effectiveness in blast performance assessment. The combination of high-spectral drone images and AI-based software analysis demonstrated nearly 99% accuracy in ore tonnage prediction models compared to LiDAR, showcasing its promising capabilities.

Jan 21, 2025

By R Stefansen

Stockyard operations are governed by the interaction between the different disciplines required to successfully schedule and control the supply chain of raw material through the stockyard in combination with the effectivity of the operation of the stockyard equipment. The system demonstrates a proven technology for implementing a centralised operation of full unmanned stockyard equipment, using a high precision absolute positioning system based on a Real-Time Kinematic (RTK) Global Navigation Satellite System (GNSS) receivers in combination with 3D rangefinders. The system implementation maps the surface profile of the stockyard inventory and allows in combination with proprietary algorithms for full operation of the stockyard machines without on-board operators. The operational impact of delayering the process by moving to a centralised operation is examined, together with the combined effect on the overall safety in the stockyard as a result of a change in reliance on operator skill dependencies. Average performance gains range from 10–20 per cent. The performance of the automation system is related to a consistency and reliability of uniform operation, which has an impact on the life expectancy and the effectiveness of the equipment. The effects of having instantaneous and correct information about the stockyard inventory volume measurement are investigated in relation towards spot price trading in current fast reacting markets.CITATION:Stefansen, R, 2017. Advanced automation for centralised stockyard operations, in Proceedings Iron Ore 2017, pp 105–110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Andreas Rohrhofer

Reliable high end automation and process optimization systems are main factors for excellent product quality, safe operation and maximized plant performance in the steel industry and its designated environmental plants. Primetals Technologies introduces new automation packages for consequent safe and cost efficient production. Many areas within the steelplant interested to be monitored and measured automatically are not implemented in the automation system due to limited access or technical reasons. A wireless, self-organizing network facilitates wide ranging data transmission in previously inaccessible areas and opens up a wide range of new opportunities. With Fluid Guard a system to detect leakages with highest accuracy and reacts properly for all kind of water cooled circuits is available, improving the safety in steelmaking process. Lance Guard can be utilized for all fully automatic and semi-automatic lance appliances, but is especially suitable for the products of Primetals Sublance Standard/2.0 and LiquiRob applications, since these systems make seamless integration particularly simple. Manual lance appliances may also be tested and diagnosed. Environmental plants have become a main part in steelmaking plants. Highest performance in combination with optimized energy consumption is the main target in Primetals Technologies’ innovations in automation optimization packages for dedusting systems. A new approach for preventive maintenance and operator assistance is introduced with the Acoustic Expert System. In combination with the new Ask cloud based system, Primetals enables a 24/7 monitoring and a whole lifetime observation of any equipment within a steelplant. Furthermore it is now enabled to check the condition of the plant at a fingertip at any time.

Aug 17, 2017