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By J. Kulas, J. Weaver, K. Hagley

An assessment of potential groundwater movement beneath the tailing impoundment at the Red Dog Mine was performed, and has indicated a unique aquifer situation within sub-permafrost groundwater at the site. The aquifer was shown to be isolated from both vertical recharge and a real discharge, and is characterized as a virtually no-flow system. The permafrost resulted in a deep aquifer with high tidal efficiency, meaning that variable surface loads are easily transmitted to the fluid. The tidal efficiency has been characterized through analysis of water level fluctuations that respond to earth tides, barometric pressure loads, and loading from the pond.

Jan 1, 2002

By Jorge Navarrete

La Corporación Nacional del Cobre de Chile produce cobre y otros subproductos a través de sus yacimientos y líneas de producción como las pirometalúrgica, hidrometalúrgica y biohidrometalúrgica. En este sentido, el presente texto señala la implantación de un LIMS para la industria minera de cobre. LIMS es una abreviatura genérica para los software de Administración de Información de Laboratorio, cuyo objetivo es relacionar la Informática, Quimiometría y Calidad.De forma que cumpla con los objetivos de adquisición y gestión de la información de pesaje, muestreo y análisis químico producida por diferentes áreas, tanto internos como externos y unidades funcionales.

Jul 17, 2000

By M Shaffer, D C. Grant, D J. Goudie, P Sylvester, C Voisey

Scanning electron microscope–Mineral Liberation Analyser SEM-MLA can be used to discriminate between hematite/magnetite in iron ores, but achieving backscattered electron (BSE) segmentation between the two minerals is difficult for particles =75 µm using typical preparation and analysis methods for the MLA based on a tungsten filament SEM (Quanta 400) with 25 kV high voltage. Preparing iron ore sample mounts using a slow-speed polishing method, and conducting the experiment on a field emission gun SEM-MLA (Quanta 650) with the high voltage (HV) setting lowered to 15 kV reduces instrument noise and results in very clean BSE images and segmentation. This method requires new X-ray standards to be acquired for each mineral identity at 15 kV because of major changes in the spectra at lower kV. However, once these X-rays are added to the mineral reference list, effective segmentation can be achieved and a proper analysis obtained.CITATION:Grant, D C, Goudie, D J, Voisey, C, Shaffer, M and Sylvester, P, 2017. Discriminating hematite/magnetite via scanning electron microscope–mineral liberation analyser in the - mesh size fraction of iron ores, in Proceedings Iron Ore 2017, pp 541–548 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D. A. Greenwood

Dr David Greenwood opened the first technical session of the conference by highlighting the diverse nature of the papers in this session but drawing attention to the common theme that each solved a particular problem. PAPER 1.1 Tony Elliott introduced his paper on deep mix-in-place soil/cement stabilisation by stressing its simplicity. The engineering solution adopted at Elland was detailed in his paper and had formed the key to success of the project. The process itself is not widely used or known in the UK, although it has the potential to achieve significant benefits, subject to proper engineering control being exercised. It was explained that although the concept was not new, development of the technique for soil modification was relatively recent. The alternatives to mechanical mixing are injection, which is very dependent on soil type, site geometry, etc, and jet grouting; both processes are soil-responsive, and not easily monitored or programmed, difficulties which can largely be overcome by mixing. To achieve this at depths to say 30m requires high-powered, high torque machines and has resulted in significant equipment development.

Jan 1, 1991

By H. Kinilakodi

In 2008, the authors developed a methodology for assessing underground coal mines for high risk for major-hazard events. It focused on major hazard-related violations of safety standards associated with high-risk conditions. Later using a sample of 103 mines with 2008 and 2009 data, injury measures and MSHA citation data were combined into a Safe Performance Index (SPI). The SPI was used to assess the relative safety-related risk of mines, including by mine-size category. In this paper, comparisons are made of SPI-associated, normalized safety performance measures across mine-size categories, with emphasis on small-mine safety performances as compared to large and medium-sized mines.

Jan 1, 2011

By H. Warren Newcomen

The southwest wall of the Lornex Pit at the Highland Valley Copper mine has been experiencing slope displacements since 1978. Measures to manage the displacements on previous pushbacks have included stepping out, scheduling pushbacks to unload the crest of unstable areas, slope dewatering and mining with intensive slope monitoring. The final pushback on this wall is currently being mined and substantial modifications to the slope geometry could prove to be uneconomic. As a result, a campaign of surface water collection and diversion, horizontal drainhole drilling and deep well drilling is currently underway to maintain an acceptable degree of stability to the end of mine life. The various factors contributing to instability, including engineering geologic controls, rock mass strength, and surface and groundwater hydrology are presented. Movement trends, displacement magnitudes and stability analyses results are also discussed.

May 1, 2002

By F. E. du Plessis

"The distinction between data suitable for process control and data subject to aliasing only becomes quantifiable with the availability of rapid real-time measurements. Expecting the dynamics of flotation to vary for different ore types, process flows and equipment types; a study was conducted to compare the dynamics of different flotation processes. The results shed light on the critical sampling intervals required for process control which in turn allows process stabilization and optimization. The technology used for the in-line measurements is based on diffuse reflective spectroscopy and has been introduced into the mineral processing industry over the past ten years. It has been widely implemented in the sulphide flotation industry in South Africa for the real-time measurement of grade.BACKGROUND AND OBJECTIVE A study was conducted by Du Plessis and Keet (2010) to quantify the minimum sample frequency required for grade and/or impurity control. The study was based on chromite data collected at 15 second intervals from the concentrate line of a flash float cell in the Platinum industry. The data captured the natural process variation of the entrained chromite through water recovery due to changes in feed parameters and flotation performance. It was found that the minimum rate of sampling required from the studied flash float concentrate was 2 minutes. This sampling interval time accounted for 90% of the variance in the process data. It was further found that a sampling interval time of longer than 4 minutes produced data with no significant correlation to reality. The dynamics of the flotation process has been misjudged in the past but can be quantified with the availability of real-time grade measurement based on diffuse reflective spectroscopy. The objective of the study was to compare the dynamics of different sulphide flotation processes through the comparison of maximum sampling interval times required to combat aliasing. All data were collected from single stream analyzers that are currently installed at mineral concentrators. The technology used is based on diffuse reflective spectroscopy."

Jan 1, 2012

By Hongyang Cao

The iron constituents selectively separated from the modified copper slags by magnetic separation and flotation.were studied. The results of magnetic separation for modified copper smelting slags show that the grinding size, current intensity and dispersant agent had great influence on grade, and recovery ratio of TFe in preparation concentrate; The results of flotation for magnetic concentrate show that the positive flotation of sodium oleate negatively upgrade the grade of magnetic concentrate, but the reverse flotation of lauryl amine and soluble starch are effective. The grade of TFe can reach 54% and the recovery ratio can reach about 90% in magnetic concentrate, when the grinding size is 45.8µm and the current intensity is 2.5A. The optimal effect is obtained by using lauryl amine as collector and soluble starch as depressant to reverse flotate magnetic concentrate, and the grade of TFe is upgraded 2.37%.

Jan 1, 2009

By Isobel Yeo, Luca Cocchi, Sven Petersen, Nico Augustin, Sean Plunkett, Ingo Klaucke

Exploration for seafloor massive sulfides is currently mainly focused on investigation for active hydrothermal vent fields. However, most of the resource potential is thought to be related to inactive, large deposits that had enough time to accumulate sufficient tonnage. At the same time, ageing of these deposits will ultimately result also in burial acted by either sediments and/or volcanic deposits. We currently lack the technologies to explore for these deposits in a time- and cost-efficient manner. In the fall of 2012 we used a number of AUV-based technologies to explore and image a sulfide occurrence at the Palinuro Volcanic Complex in the Tyrrhenian Sea (Mediterranean Sea; Fig. 1) where sampling and drilling have documented a buried polymetallic barite-pyrite dominated site (Petersen et al., 2014). Sulfide mineralization is here covered by volcaniclastic and pelagic sediments and only red sediment staining and the presence of few tubeworm bushes indicated recent hydrothermal activity - black smoker venting is absent. We used AUVbased high-resolution bathymetry, sidescan sonar imaging, subbottom profiling, as well as magnetics to describe, in a quantitative way, the previously known sulfide-bearing areas as well as to successfully explore for new hydrothermal sites including large chimney structures (Figs. 2). Additionally chemical sensors (CTD, Eh, turbidity) investigated the water column for signs of hydrothermal activity in areas not previously investigated, but at the end, only weak anomalies were found in the southern part of the summit.

Sep 1, 2014

By D. H. Diering

The paper takes the reader into the depths of a modern ultra-deep South African gold mine and gives a perspective on the vertical and horizontal extent of the tunnel networks in such a mine. Depending on the mine design layout employed, tunnels once excavated are subjected to various levels of stress change over their life time, and the support requirements are explained. It is suggested that shotcreting is the only viable ultra-deep level support medium, and after looking at the latest developments, the logistical problems are put forward. In an effort to overcome most of these problems, the South African ultra-deep mining industry embarked on a collaborative research programme in 1998. The importance of tunnelling and in particular tunnel support as a critical technology for future successful ultra-deep level mining is stressed. While not yet fully ?on top of? these problems and challenges, our industry is now fully addressing them and we expect to make significant progress during the next 4 to 5 years.

Jan 1, 2000

By D FitzGerald, S Jakica, R Paterson, J Silic

A new 2.5D airborne electromagnetic (AEM) algorithm has been developed by Intrepid Geophysics and Jovan Silic & Associates. The advantage of 2.5D (2D geology, 3D source) AEM inversion in 3D geological mapping applications and identification of conductive drilling targets, compared to the more commonly used conductivity-depth imaging (CDI) transforms or 1D inversions, are demonstrated using examples from banded iron formations (BIFs) and other geological settings. We show emerging AEM systems are capable of providing estimates of economic rock unit thicknesses, dips and fault definition at an accuracy that mitigates the need for pattern drilling.The 2.5D inversion application used in this work and described in Silic et al (2015) is a substantially changed version of ArjunAir (Wilson, Raiche and Sugeng, 2006), a product of CSIRO/AMIRA project P223F. The changes include a new forward model algorithm and a new inversion solver. The application enables the accurate simulation of 3D source excitation for full domain models inclusive of topography, non-conforming boundaries and very high resistivity contrasts. Solution is accurate for a geoelectrical cross-section, which is relatively constant along a strike length that exceeds the AEM system footprint.The major innovation includes a new inversion solver with adaptive regularisation, which allows the incorporation of a misfit to the reference model and the model smoothness function.Memory usage has been dramatically reduced and is estimated prior to execution. For speed the software has been parallelised using Intel message passing interface (MPI) and can be used on standard computing hardware or computing clusters. Data from survey lines with lengths exceeding 100 km can be inverted on high end laptop computers.We allow flexibility in the selection of components and in the estimation of noise.AEM inversion examples are shown for surveys from BIFs, base metals (volcanogenic massive sulfides) and geological mapping projects and the results are compared with known geology and drilling. We demonstrate the much improved mapping and target definition delivered by this inversion method when compared with the other more common transforms or inversion methods used on these projects.CITATION:Paterson, R, Silic, J, FitzGerald, D and Jakica, S, 2017. High accuracy .D airborne electromagnetic inversion method for banded iron formation and other geological settings, in Proceedings Iron Ore 2017, pp 319–330 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Frederic Masse

With widespread acceptance in the market place, many engineers are choosing ground improvement techniques to provide suitable foundation subgrade at sites that would have traditionally required deep foundations. This paper discusses the Controlled Modulus Columns (CMC) ground improvement technique and some case histories highlighting the use of this technique for retail development sites. CMC are a sustainable and cost-effective ground improvement technology that transmit load from the foundation to a lower bearing stratum through a composite CMC/soil matrix. The CMC installation is also an attractive option from an environmental perspective because it utilizes reverse flight augers, which displace the soil laterally. This installation technique achieves two goals: it densifies the soil around the CMC, which improves load transfer into the element and avoids spoil and its disposal. Through the introduction of two cases histories, we will present the key benefits of the CMC technology. Each case history will clearly illustrate how a CMC solution can reduce the overall cost of a project when compared to a more traditional type of deep foundations. They will also show how the use of CMCs has benefits that relate to the overall sustainability of the project. While CMCs are an attractive financial and sustainable option, they have also demonstrated that the performance of the system is comparable to that of deep pile foundations. Because CMCs are a relatively new technology many potential users are not aware of its benefits. While we discuss the use of CMCs to support buildings in this paper, CMCs also have been used for a variety of other applications including foundations for tanks, mechanically stabilized earth (MSE) walls, and embankments

Jan 1, 2011

By P J. Grobler

The current commodity boom is depleting the ore bodies at a rate not seen in the past. As the existing ore bodies get depleted, only the more inferior bodies are left for exploitation. This places an emphasis on beneficiation to upgrade the lower grade ore to high-grade feedstock for downstream processes. This paper discusses the role of dense medium separation in this quest for high-grade feedstock for the future. It covers the production and utilization of ferrosilicon and gives a future perspective of the technology. It concludes about the way ahead and the challenges facing the processing fraternity and mining industry.

Jan 1, 2006

By Jack L. Taylor

As expected from similar crystal structures and favorable atomic size factors, titanium, vanadium, and molybdenum are completely soluble in one another above the transformation temperature of titanium. The fl phase parameters of the continuous solid solution are shown graphically. Limiting compositions for retained fl phase have been determined. VANADIUM and molybdenum both have body-centered-cubic structures at all temperatures and, from the atomic diameter comparison factor, 3.9 pct, would be expected to form a complete series of solid solutions. The existence of complete solubility has been confirmed by work' at the Jet Propulsion Laboratory. Furthermore, vanadium and molybdenum have favorable atomic size factors to form complete binary solid solutions with the B phase, high temperature form of titanium, which also has body-centered-cubic structure. Pietro-kowsky and Duwez' and Hansen et al." have established the existence of the complete series of solutions in these binary systems. It would be logical, therefore, to expect that p-titanium, vanadium, and molybdenum would be completely soluble in one

Jan 1, 1957

By Fulvio Tonon

And Rabcewicz said ?tunnels should be driven full face whenever possible.? ADECO, which stands for ?Analysis of Controlled Deformations in tunnels,? now allows us to fulfll Rabcewicz?s dream in any stress-strain condition. In order to achieve that dream and its consequent control over cost and schedule, however, NATM must be abandoned for the ADECO. The paper presents the basic concepts in the ADECO approach to design, construction and monitoring of tunnels together with some case histories, including: full face excavation for Cassia tunnel (width of 22 m, height of 14 m) in sands and silts under 5 m cover below an archeological area in Rome, Italy; Tartaguille tunnel (face area > 100 m2) advanced full face in highly swelling and squeezing ground under 100 m cover where NATM led to catastrophic failure, France; and 80 km of tunnels (face area > 100 m2) advanced full face in highly squeezing/swelling ground under 500 m cover for the high-speed railway line between Bologne and Florence, Italy (turnkey contract).

By Bengt H. Fellenius

Session 2, Deep Foundation without Soil Excavation, has attracted no fewer than 22 papers dealing with subjects from soil improvement by grouting, injection, and deep mixing techniques through vibroflotation and special piles, including aspects pertaining to conventional driven and bored piles. In the short time available, it is not possible to both do justice to the papers and provide a critical review of the state-of-the-art. Instead, to meet the objective of making the next half hour worthwhile to the audience, I have chosen to comment on a few special points brought forward in the papers and thereafter to discuss more in detail a couple of aspects I have deemed to be of general interest. Four papers deal with jet-grouting, injection, and deep mixing techniques: DOMSKI, J. J. Reinforcement of subsoil under the foundations of historical buildings in Cracow using deep injection technique. RESTELLI, A. B, BERTERO, M., and LODIGIANI, E. Deep mixing technology to improve the bearing capacity of a very soft clayey soil under an earth embankment.

Jan 1, 1994

By William Reisz

Over the years as surface mining operations have become more sophisticated, angle drilling has become a more popular blast design technique, especially in areas where overburden and stripping ratios have increased. Another method of blast design is the staggered pattern, which greatly improves explosives distribution within the blast. While both methods present some engineering challenges, this paper will discuss how the two methods can be combined to enhance fragmentation, improve cast percentage, drill production ratios and highwall control. A practical engineering approach will be presented as well as a discussion on the discipline required to maintain a quality blasting plan.

Jan 1, 2002

By S. A. G. Poppen, M. B. Mirza, A. I. Cooley

The U.S. Department of Energy (DOE) is responsible for siting and constructing a licensed geologic repository for commercially generated high-level nuclear waste. Within DOE, the Office of Civilian Radioactive Waste Management (OCRWM) Program has this responsibility. To accomplish this mission, the OCRWM Program is engaged in a multidisciplined effort to identify, qualify, and develop repository sites. The current strategy of the OCRWM Program is to identify candidate repository sites in basalt, tuff, and salt and to develop exploratory shafts at those sites. Within OCRWM, the Salt Repository Project Office (SRPO) identified the salt site for the development of exploratory shafts. The proposed Exploratory Shaft Facility (ESF) in salt will have several primary purposes. The shafts will provide access to the reference repository horizon to permit in situ testing of the salt horizons in order to satisfy the following data acquisition needs: • Verification of the salt repository design parameters and validation of performance assessment models • Demonstration of the constructibility • Capability to adequately seal penetrations into the salt An exploratory shaft is required by 10 CFR Part 60 for the conduct of in situ testing at depth prior to submittal of a license application for construction authorization of a repository. Therefore, construction of an ESF will also facilitate the licensing process.

Jan 1, 1987

By Reda M. Bakeer

"Measurements obtained during load testing of two steel H-piles driven at a site in Northeastern Mississippi are discussed. The general site conditions, equipment used, testing procedures and results of the pile load tests are presented. Both piles were tested in compression and one of the piles was subsequently tested in tension. The piles were instrumented with strain gauges and extensometers to measure the mobilized soil resistance and pile movement. Three different “zero strain” conditions were used to determine the mobilized soil resistance and residual loads due to driving or a load cycle. It was concluded that the effect of residual loads on driven piles could be significant. Driving residual loads influenced the magnitude and distribution of the load transfer curves more than those due to a load cycle. Results of the tension test were impacted by the residual loads from the previous compression test performed on the same pile.INTRODUCTIONSeveral factors affect the performance of a deep foundation system including the subsoil conditions, loading settings, pile type and installation method. Residual stresses develop in piles particularly due to pile driving, but they are typically not accounted for in the analysis (Fellenius 2002). Siegel and McGillivray (2009) presented an assessment of residual loads measured during load testing of instrumented auger-cast-in-place (ACIP) piles. The magnitude and distribution of residual stresses along the pile shaft and toe depend on the pile installation method, previous load cycles and time effects. Poulos (1987) reported that residual load due to driving at the pile toe is independent of pile driving equipment and may significantly affect the results of a pile load test. Hunter and Davisson (1969) reported results of pile load tests performed in compression on fully instrumented piles driven in cohesionless soils along with a discussion of the effects of residual loads. Tension loads of about 445 kN (100 kips) were measured at the pile toe after driving. Unloading residual compression load at the toe was detected as “apparent” tension since the instrumentation was zeroed prior to the test. The researchers suggested a graphical approach to obtain the “corrected” load distribution curves considering that residual load will dissipate following the tension test. Holloway et al. (1975) conducted a study on the effect of residual stresses due to pile driving and developed a computer software that accounts for residual loads. Briaud and Tucker (1984) suggested a method to account for residual loads based on the results of 33 pile load tests performed in mostly cohesionless soils."

Jan 1, 2017

By Rory Cameron, Chuck Edwards

"Stringent environmental performance criteria and regulations, and the desire to minimize water use have made membrane-based treatment and separation processes an attractive option. This has lead to many advances in all aspects of the technology. Membrane separation processes have found application in sea water desalination, brackish water treatment, decontamination of ground water, and wastewater treatment. Development of membranes with better resistance to harsh feed conditions has created new opportunities for the broader application of membrane separation technologies to mineral processing streams. There are examples in mineral processing operations, including treatment of acidic drainage, pre-concentration of pregnant leaching solution in heap leaching operations, separation of acids and metals from waste streams and intermediate process streams, as well as gold and cyanide recovery from a heap leaching operation. This paper provides a brief overview of membrane technology principles, followed by a discussion of current membrane technology applications relevant to the mining and mineral processing industry. The paper further explores the potential for the application of membrane separation as an integrated component in mineral processing operations.INTRODUCTION Increased regulatory pressures, emphasis on water conservation, and scarcity of water in arid regions have resulted in substantial changes in industrial practices in recent years. As a result, many industries have become more open to adopting innovative technologies such as membrane separation. The mining industry, which is typically very conservative, has adopted membrane separation as an effective end-of-pipe solution for effluent and acidic drainage (AD) treatment; however, its use as an integrated component in plant operations has progressed more slowly. With increasingly stringent environmental regulations coupled with the desire for low- and zero-discharge operations, the use of membrane separation technology for achieving acceptable environmental performance may be unavoidable in the future. The relatively small footprint requirement, versatility, and modular construction of membrane separation units facilitate their introduction into existing processes with a suitable feed stream. Membrane separation is not a stand-alone process that provides the ultimate solution to water and wastewater treatment; however, it can often be economically added to conventional waste treatment plants to increase throughput and/or decrease contaminant output (Mortazavi, 2008). Although membrane separation technology has become an established separation technique that is widely used in drinking water production and other industries, it is still considered an emerging technology within the mining and mineral processing industry. This technology offers many potential benefits such as clean water recovery from wastewater, significant reduction of volume requiring conventional treatment, decreased usage of reagents, and acid recovery, all of which lead to increased treatment efficiencies and lower reagent consumption. This could translate to smaller and more efficient plants with lower capital and operating costs and lower environmental impacts. Plant expansion may be facilitated by incorporating a membrane separation unit operation in order to utilize existing treatment systems at higher throughputs."

Jan 1, 2012