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By Colin P. Skidmore

Long touted as Australia?s fourth uranium mine the sediment-hosted Honeymoon Uranium Project is close to commercial production using insitu-leach mining methods. Uranium mineralisation occurs as pitchblende coatings on unconsolidated quartz sand and gravels within a stacked aquifer system in a buried palaeochannel located in the Curnamona Region of South Australia. A final NI43-101 Feasibility Study is close to completion which has included extensive delineation drilling using PFN technology to accurately measure uranium grade and distribution. This data integrated with a detailed 3D sedimentalogical model is being used to optimise wellfield and plant design.

May 1, 2006

By Yan Jie

The oxygen-enriched bottom-blowing continuous converting process for copper matte was recently developed by the China-ENFI Engineering Corporation. The first commercial plant based on this technology was successfully commissioned at the Yuguang smelter in China in March 2014. The present paper describes this new continuous converting process and compares technical characteristics with other continuous converting processes including: Kennecott-Outokumpu flash converting, the Mitsubishi Process, the Noranda Converter and TSL continuous converting. The bottom-blowing oxygenated continuous converter with competitive capex and opex costs is seen as an attractive alternative to the Peirce-Smith converter.

Jan 1, 2014

By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American?s suite of specifications for gearless mill drives (?GMDs?). These specifications are based on experiences in both Anglo American?s and others? operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Nov 1, 2011

By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American’s suite of specifications for gearless mill drives (“GMDs”). These specifications are based on experiences in both Anglo American’s and others’ operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Jan 1, 2012

By R. Lanthier, A. Broussaud, J. C. Guillaneau, D. Hodouin

This study presents a method for upgrading the information extracted from the measurements given by the sensors of a pilot grinding circuit. For that purpose raw signals are combined to process models for extracting, through filters, the best information on the process state. Two different filters are used; one is based on steady-state mass balance constraints and the other one uses dynamic mass balance equations allowing for material accumulation in the equipment. The filters are designed and tuned with the help of a grinding circuit dynamic simulator and are then implemented in the pilot plant. Their performances and usefulness are discussed.

Jan 1, 1989

By N. Morrison, I. Holl, R. Welyhorsky, A. Hempstock

ABSTRACT: The Victor diamond mine is located in the James Bay lowlands, 90 km west of the First Nations village of Attawapiskat. The project was the first of its kind in northern Ontario. The process plant was designed to produce a 95 to 98% by weight diamond concentrate through three stages of comminution, dense medium separation, and proprietary X-ray technology for final recovery. The plant was commissioned over a period of six months, commencing prior to substantial completion of construction. Through effective planning of the commissioning phase, the Victor mine start-up was safely completed nine months ahead of schedule.

Jan 1, 2011

By C. Cekerevac

The paper addresses some geotechnical issues related to the construction of the Deriner dam and HEPP. Design considerations and rock stabilization measures are presented for the excavations which took place in a highly fractured and weathered rock mass prevailing on site. Particularly, the shallow excavations for the overflow spillways tunnels are discussed. These present huge openings that are 12 m wide and 18 m high in portal areas, with an overburden of approximately 20 m, for which numerical finite element analysis and structural discontinuity analysis have been performed to ensure safe excavation process and future operation.

May 1, 2009

By Nirmal Weerasekara, Jochen Franke, Malcolm Powell, John Favier

Mill liners serve the dual purpose of protecting the shell from wear and transferring the rotary motion of the mill to an effective grinding action. As the liners wear, the efficiency of energy transfer changes, so there is balance between liner profile for wear and for milling efficiency. A tool that can simultaneously predict the evolution of the liner profile and the associated change in milling efficiency should prove most useful in optimal liner design. This paper presents such an approach, based on measured 3D liner profile data informing 3D DEM simulations of charge motion and liner wear modelling.

Jan 1, 2012

By Alexander Potapov, Lawrence Nordell

A Conjugate Anvil-Hammer Mill (CAHM) has the potential to replace conventional crushers and SAG mills, with their respective conveyors and stockpiles, in a SABC circuit. It may improve comminution circuit efficiency by 100%. CAHM compresses rock in a more efficient way, similar to 19th century stamp mills, which follows the fundamental research of Schönert (1990 & 1996). CAHM efficiency is being proven through the use of ROCKY (2011) Discrete Element Method (DEM). ROCKY features allow it to simulate realistic comminution. CAHM is customizable with many geometries that are rock-property specific. ROCKY’s wear modeling compliments the structural integrity of the design.

Jan 1, 2012

By Robert Walker

Agenda ? Investment thesis ? Engagement ? Competitive advantages Corporate engagement ?The ESG Services team carries out engagement activity with the companies in the Ethical Funds portfolio on behalf of investors ?Each year about 50 companies (20% of our assets) are placed on our Focus List based on assessment of significance and severity of ESG risks and the extent of our portfolio exposure ?We engage in direct discussions on material ESG issues ranging from climate change to human rights to executive compensation ?This enables the team to gain insight into how management is addressing various risks to the business and encourage positive change where gaps exist

Aug 1, 2013

By T. Ward, K. Shah, K. Murray

The mining industry is processing deposits with ever decreasing grade at ever increasing operating costs while margins are under constant pressure by material substitution and recycling. We are reaching the point where building it bigger just isn’t good enough as social and environmental constraints become more intense. In response to the growing demands on our industry, Goldcorp has embarked on a journey to increase resources by converting Waste to Ore. Gravity pre-concentration and sensor sorting testwork has been completed on samples from our Canadian operations in order to determine the amenability of our mineralized waste to sorting and upgrading. As expected some material was amenable to sorting and a review of the economics supported demonstration plant testing. The ability to economically sort mineralized waste into ore and barren rock is being demonstrated by Goldcorp. It has been made possible by leveraging the experience mineral sizer manufacturers have gained in the oil sands and hard rock applications, seeking more energy efficient screening machines and embracing the advancements that ore and recycling sorter suppliers have achieved. The paper will discuss the testwork and results achieved to date from both the lab and demonstration plant.

Jan 1, 2018

By J. G. Henning, T. R. Yu, J. E. Croxall

"Test work was carried out to investigate the thermal response of loose and solid rock under varying environmental conditions. The primary interest was to develop a technique that could be used to increase the thermal variation between loose and solid rock for better detectability of loose rock underground with a thermal imaging infrared scanner.A variety of thermal enhancement methods were evaluated both in the laboratory and in the mine environment. Air temperature variation created by the exhaust from diesel driven, mobile mining machinery was studied in detail. When sufficient hot exhaust was supplied to the air, unsteady thermal conditions became more pronounced on the rock surf ace. This allowed a greater percentage of loose rock to be detected by a high-resolution infrared scanner within minutes.The degree of thermal enhancement of loose rock was found to be dependent directly on the thermal conductivity of rock, looseness, air temperature change, and inversely on the size of loose, airflow rate and distance downwind from the heat source. It was also found that an air temperature rise of at least r c, or rock temperature differential of1°C was necessary for minimal thermal enhancement required f or infrared detection."

Jan 1, 1990

By Vanessa C. Koppe

During ore body modeling normally additional samples are required to improve resources evaluation and mining planning. At this stage one rises the question about where additional samples should be located. Regular sampling pattern seems to be a reasonable choice, since all the regions within the deposit receive the same number of samples without a clear clustering. Nevertheless, values for certain attributes (grades for instance) from a mineral deposits may behave more erratic in some regions than others. Consequently, by adding samples to these regions could bring more benefit for reducing the uncertainty related to a transfer function such as Net Present Value (NPV), instead of adding samples to location of low grade uncertainty. Thus, for a given number of additional data, the test of a regular pattern and a pattern which add samples on areas of high uncertainty of the attribute of interest is worth. This paper presents an algorithm that allows the construction of these two patterns, automatically, on a software commonly used in the mining industry. The algorithm leads to a fast analysis on the efficiency of the two patterns in reducing the uncertainty associated with a transfer function.

Oct 1, 2009

By J. Buckle

"Recognition of the diamond potential of the Wawa subprovince was initially determined from regional data using a kimberlite model. The world’s largest stable Precambrian craton, the Superior Province, is considered to be favourable for the emplacement of diamondiferous kimberlite. The Wawa area is located near the intersection of intra-craton structures visible in the regional magnetic data.The Enigma project is located north of the town of Wawa in northern Ontario. From field evidence and background research, it became obvious that in the Wawa area there were at least two potentially diamond-hosting events, Archean lamprophyric volcaniclastics and Proterozoic kimberlites. The host lamprophyric rock does not contain the classical KIM signatures. However, to complicate the Enigma, stream sediment samples within 200 m of the diamond-bearing lamprophyre produced a typical suite of kimberlite indicator minerals.The micro- and macro-diamond content of the Wawa lamprophyric volcaniclastic rocks is typically 0.2 ct/t to 1 ct/t, although it can be higher locally. The economic diamond potential of these Archean dykes, sills and irregular lamprophyre bodies is still under-explored (Kaminsky, 2002, unpubl.). Oasis Diamond Exploration is currently exploring the area using geophysical, geochemical, and geological data."

Jan 1, 2002

By L. M. Ame, W. D. Harwood

"This paper outlines a management philosophy aimed at promoting employee involvement, quality and process improvement at Inco 's Thompson operations. It describes the use of statistical process control techniques, lessons learned and examples of progress.IntroductionThis paper provides an overview of the Manitoba Division's performance through the promotion of greater employee involvement, quality and process improvement. Having learned from other practitioners o f quality management, the Manitoba Division believes its experiences are applicable to all mining and other businesses.The Thompson operation consists of two underground mines, an open pit, a mill, a smelter and an electrolytic refinery. The workforce consists of 2000 members. The main products are electrolytic nickel slab and proprietary nickel rounds. Production levels are currently at capacity in response to heavy market demand.Paralleling much of the mining industry the corporation was faced with six years of decreasing nickel prices (Fig. I). Inco Limited survived by focusing on productivity and cost improvement. Manitoba Division productivity improved 32070 over three years beginning in 1982-the worst financial year in the company's history (Fig. 2). A real unit cost reduction of 20%, net of inflation, was also achieved (Fig . 3)."

Jan 1, 1990

By Terry McNulty

"Previous papers (McNulty 1998 and 2004) have dealt with the causes of successful and less successful achievement of design production rate by new processing plants in the minerals industry. Examination of many case histories has allowed the construction of curves or profiles that represent projects with similar characteristics that equate to differing degrees of care exercised during the project development phase. Simplistically, decreasing care is reflected by increasing risk and a heightened likelihood of poor technical and/or financial performance.This contribution provides an update, including recent case histories, and presents a modified Series 1A curve that includes the best 23 case histories, out of a total of 81 examined, or 28%. This is done to show that some very carefully developed and executed projects can ramp-up quickly and that owners of new projects should avoid being too pessimistic in projecting early cash flow if they are certain that they have done their homework. The role of metallurgical process development in the reduction of project risk is discussed and several financial analyses are presented that express the potential monetary value of a well-designed and professionally executed metallurgical program."

Jan 1, 2014

By Chris Brothen

The introduction of new technology in mine operations has provided real opportunities for increased efficiencies and production gains which translate into enhanced profits. Computing and network technology usage has become integrated into surface mining operations and on average these investments in technology have proven beneficial for efficiency and productivity improvements. Embracing new technologies however, does not guarantee positive results. The expectations or improvements derived through the technology must be confirmed and clarified well before implementation. Tire Pressure and Temperature Monitoring Systems are an excellent example of an existing technology that can provide full time automated performance measurements of tires operating under harsh conditions and environments. Prompt warnings or alarms signaling when a tire has exceeded operating capacities will provide savings through lowered maintenance costs and increased productivity. To truly quantify the projected savings in tire life, fuel consumption, and increased levels of production, all costs associated with the technology, both direct and indirect must be considered. Apart from the initial cost of the system implementation, ongoing maintenance and support costs must be considered as well as the costs of system integration into existing mine operations

May 1, 2008

By N. Haghdadi, D. M. Maijer, A. B. Phillion

B206 is a recently-developed high-strength Al-Cu casting alloy with reduced Ti and Fe, as compared to the well-known AA 206 alloy, for improved hot tearing resistance. In the current study, the solidification kinetics of this alloy as a function of cooling rate from 1 to 15 K/min were studied using differential scanning calorimetry (DSC) and microscopy. Specifically, the evolution in fraction solid, grain size, and secondary dendrite arm spacing have been characterized. The DSC results show the occurrence of three peaks during cooling from the liquid state, which are related to the formation of primary aluminum, a pre-eutectic intermetallic, and the eutectic phases. Thermal analysis also indicates that while the liquidus temperature is not sensitive to the cooling rate, the temperatures at which the pre-eutectic and eutectic phases form are strongly coupled to the rate of heat extraction. A decrease in the latter temperatures was observed when the rate of solidification was increased, leading to a lengthening of the freezing range of the primary phase. The results will be useful for improving B206 casting processes, specifically through modification of mould cooling conditions.

Jan 1, 2014

By X. X. Wu, Q. Zhang, R. H. Fan, Y. J. Feng, J. D. Liu, P. Z. Zhao

In the present study, AA6016 automotive sheets with different grain size were fabricated through changing fabricating parameters, and the effects of grain size on the bendability were studied by bending test and optical microscopy. The results showed that the sheet with coarse grains exhibited poor bendability, and some micro-cracks were revealed at the surface of the bending samples. While the sheet with fine grains exhibited good bendability, and the bending samples showed smooth surface. Shear bands on the cross section of bending samples were observed. It was found that samples with coarse grains had more shear bands. These shear bands distributed in bundles, which facilitated the formation of continuous neckings and micro-cracks. However samples with fine grains had less shear bands, which distributed uniformly. The decrease of grain size could not only hinder the formation of shear bands, but also improve the homogeneity of its distribution during bending. On the other hand, refining grains could increase the amount of grain boundaries, which impede the propagation of shear bands. Hence the decrease of grain size could hinder the formation of continuous neckings and micro-cracks during bending, resulting in the significant improvement of the bendability.

Jan 1, 2015

By E. I. Vargha-Butler

The determination of surface tensions and contact angles of coal particles is of great interest for coal beneficiation processes such as froth flotation and oil agglomeration and for the inclusion of coal particles into oil droplets as a means of enriching the fuel. Methods for contact-angle measurements on small irregularly shaped solid particles have not been available in the past. Therefore, we recently developed a novel technique to determine contact angles and surf ace tensions of coal particles. Two types of bituminous and one type of subbituminous coal particles have been tested. The technique used is called the freezing-front technique and it considers the behaviour of the test particles (in the range of 20-250 pm) at the solidification front of carefully selected, well-defined solidifying melts (matrix materials) such as thymol, biphenyl, naphthalene, salol and 2-phenyl phenol.The results show that the technique works well, providing quantitative and detailed information on the wettability of coal particles. The sensitivity of the method is so high that a difference in contact angle of approximately 4 degrees between the smaller and the larger particles is clearly registered.

Dec 1, 1981