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By K. Sawada

Along with the expanding demand of copper concentrate in Asian countries, custom-smelters have confronted with difficulties of low TC/RC. Now, Japanese Copper Industry have 2 options; investment in mine development and/or recycling of copper scraps. The strategy of global mining companies is analyzed, and implications for Japanese Copper Industry will be discussed from the viewpoint of sustainability of smelters in Japan.

Jan 1, 2014

By R. E. Baylis, M. R. Tolley, S. Singh, A. J. Murray, R. Boden, L. E. Macaskie, T. P. Hathway, D. Vavlekas

We report rare earth element (REE) recovery using immobilized Serratia biofilm depositing metal phosphate via a robust enzymatic mechanism. Activity was approximately halved at pH 3.5 and restored at pH 5.5. REE(III) was recovered selectively against Th(IV) but the method was non-selective between different REEs (La, Y, Eu, Nd). Biofilms were active for a year (half life of ~ 3 months). The activity of aged biofilm was enhanced by pre-nucleation (‘priming’) with NdPO4 prior to onset of flow-through conditions. The use of different ‘priming’ metals and bacteria via a combinatorial approach revealed some REE selectivity through the selective exclusion of specific REEs.

Jan 1, 2014

By Bian Xue, Wu Wenyuan

High quality, mono-dispersed, hollow CeO2 microspheres with high surface area were produced by a spray pyrolysis method at 700oC. CeCl3 was used as the raw material of the process rather than Ce(NO3)3 because the latter is relatively difficult to obtain in industrial quantities. X-ray diffraction and electron microscopy results confirm the high quality synthesis of hollow CeO2 microspheres with narrow size distribution, good mono-disperse, and good reproducibility. The process of the formation of mono-dispersive CeO2 microspheres was investigated by chemical dynamics and a possible mechanism is proposed. This simple method for synthesis of CeO2 microspheres is easily scaled up to fabricate other metal oxide nanostructured materials at industrial scale.

Jan 1, 2014

By G. R. Baiden

This paper discusses the application of Load-Haul-Dump (LHD) machine teleoperation in combination with a guidance system for single operator control of multiple IJIDs. A system accomplishing these goals has been tested at Copper Cliff North Mine of Inco Limited. This development uses a high-speed, high-capacity production network to teleoperate an LHD during loading and dumping by using 3D video and radio remote control. Following loading, the operator dispatches the LHD using an automatic guidance system to traverse the drifts to the orepass. Remote dumping is done at the ore pass and then the machine returns to repeat the procedure. This has significant productivity gains and improvements in safety. Productivity is improved because operators are involved only in the loading and dumping part of the process. This frees the operators to utilize their time more effectively, loading or dumping a particular machine, while other machines with guidance systems continue to work travelling and/or automatically dumping ore in the ore passes. Safety is improved as the operator is located on a remote control station. Automatic dumping will be incorporated as a future development.

Jan 1, 1994

By J. O. Marsden

Over the past eight years, Phelps Dodge (a division of Freeport-McMoRan Copper and Gold, Inc.) has developed a suite of proprietary hydrometallurgical processes for the treatment of copper concentrates as an alternative to conventional smelting and refining technology. The technical viability of two processes has been commercially demonstrated in a large scale plant at Bagdad, Arizona, designed to process approximately 52,500 metric tons per year of concentrate containing 30.5% copper. The first process utilizes high temperature (225°C) pressure leaching, followed by countercurrent solid-liquid separation, and then blending of the copper-bearing solution with low grade stockpile leach solution for subsequent treatment by SXlEW for copper recovery. The second process uses super-fine grinding, medium temperature (l60°C) pressure leaching, followed by solid-liquid separation, and treatment of high grade copper-bearing solution by direct electrowinning to recover the bulk of the copper values. The latter process will be utilized at Morenci in a commercial facility designed to treat mixed chalcopyrite-chalcocite-covellite concentrates. This facility is scheduled to start up in 2007. Other flowsheet options have been developed by Phelps Dodge for application to a variety of concentrate materials in specific situations. Examples of various flow sheet options are presented in this paper, and the advantages and disadvantages associated with each are discussed in detail.

Jan 1, 2007

By Asfahani. Jamal, Randa Mohamad

"Abstract - Electrical and structural characteristics of formations favorable for sulfur occurrences in northeast Syria are described using geo-electrical prospecting methods. Simple (VES) and combined (CVES) Schlumberger vertical electrical soundings and geo-electrical profiling using a Wenner configuration were applied to the Teshreen structure. Six profiles (A, B, C, D, E, and F) at the borders of anticlines, where positive and negative structures are joined and salt formations have a tendency to disappear, were studied.Secondary structures, characterized by high apparent resistivity exceeding 3000 Ohm.m were located on each profile using a Wenner profiling configuration. These secondary structures are demonstrated to be favorable for sulfur prospecting by both drilled wells and vertical electrical soundings. Traditional interpretation of the 84 VES measurments is supported by data from 14 CVES measurments. The CVES technique is a powerful tool, due to its improved resolution of the electrical boundaries.Thicknesses and resistivities of the Lower Al-Fares, Al-Garibeh, and Al-Dibbaneh formations were determined through the interpretation of VES measurments. The same VES measurments were then interpreted using the Pichgin method, whereby all the subsurface tectonic features were determined for depth penetration corresponding to AB/2 = 1000 m. The integration of the first and second VES phases creates a clear picture of the subsurface, including tectonic, geometric, and geoelectrical information. In summary, the sulfur occurrences in the research area are controlled by tectonic paths that are well defined by geo-electrical methods. These diverse geo-electrical methods could be used successfully for sulfur prospecting in similar environments."

Jan 1, 2002

By Emmanuel John M. Carranza, Martin Hale

Abstract- An application of logistic regression to mapping of gold potential in the Baguio district of the Philippines is described. Categorical map data such as lithologic units and proximity classes of curvi-linear features, based on spatial association analyses, are quantified systematically and used as independent variables in logistic regression to predict the probability for presence or absence of gold mineralization. Regression experiments to compare between using all independent variables that are associated spatially with the response variable and using only statistically significant independent variables are performed. The results of the regression experiments are similar; however, the use of all independent variables produces slightly optimistic results but better prediction rates for the known gold deposits in the test district. At least 68% of the ‘model’ large-scale gold deposits and at least 76% of the ‘validation’ small-scale gold deposits were predicted correctly. The predicted geologically favorable zones are also similar to delineated geochemically anomalous zones. The technique presented using logistic regression as a data integration tool is effective for geologically constrained technique of mapping mineral potential.

Jan 1, 2001

By S. Burling

Australia has a number of uranium deposits, but they vary significantly in their mineralogy, grade and textural characteristics. Therefore, information from traditional (or conventional) sources regarding the fundamentals of leaching the uranium and gangue minerals is not always applicable when studying particular ores. Empirical studies on particular ores can be effective in understanding leach systems and can lead to improvements in process design, but there remains a lack of fundamental understanding which is necessary for ongoing process optimisation as ore bodies continue to vary. ANSTO Minerals has undertaken a program of work to address some of the fundamental questions of uranium leaching, including the unexpected impact for some ore types of leaching at high oxidation potential.

Aug 1, 2010

By T. Stergiou

An extensive research is being carried out on the shaft furnace operation in order to minimize down-times and reduce operational cost. The need to increase the scrap percentage on the charging mix, together with the need of cheaper spare parts has led to the investigation of alternative materials for the burner system on the shaft furnace. This system consists of a burner block and a flame holder. Traditionally these items are constructed either from SiC ? oxide bonded or SiC-nitride bonded. A lot of problems have been confronted over the past 8 years of operation. Usually, large cracks are formed on both flame holders and burner blocks. This resulted in leakage of combustion gases to the back of the lining and a quick erosion of it. Additionally, the burner blocks suffer from chemical erosion, due to the increased amount of scrap used in the charging mix and the presence of slag inside the furnace. Alternative materials such as stainless steel for the flame holder and alumina-chromia refractory for the burner block have been tested in terms of life-time and resistance on chemical erosion. Furthermore, additional changes have been made on the burner block design in order to alter the flame shape and improve the scrap melting operation.

Jan 1, 2007

By G. A. Buckland

"The development, in Ontario, of a common industry-wide program for the development of skills for employees in underground hard-rock mining is described. This program is designed to increase the productivity of individual workers by improving their skill levels, while at the same time ensuring that employees are instructed in the requisite safety and health aspects of performing various underground tasks. The program's development through a management-labour-government tripartite approach is described. How this program was coordinated with new Government Regulations on Occupational Health and Safety dealing with mandatory training of underground employees is also outlined. IntroductionThis paper will describe briefly what modular training is all about and outline why, and how, it was developed in Ontario on an industry-wide basis. Simply stated, what's been accomplished to date is an industry-wide program for developing the mining skills of underground production employees.The basic objective of this program is to improve the productivity of underground workers. It involves developing an employee's skills to improve his productivity and, because working productively involves knowing how to do a job safely, the program includes instructing an employee in the various safety and health aspects of underground work. An important and, I believe, distinguishing point about the development of this program is that it has been done with the full participation, cooperation and commitment of management, labour and government.It's of considerable interest to note that companies in Ontario who are now using this program are finding that new employees are approximately six months further advanced in productivity than was the case before its use, and in some cases the frequency of accidents has shown a reduction among those employees who have taken this program as compared to those who haven't"

Jan 1, 1980

By G. A. Highcock

"Operations started at BCL in December 1973J and the smelter is currently in the seventh year of its fifth campaign. The next major shutdown is scheduled for 1995. During the current campaign, a number of major on-line refurbishments have been carried out without any significant disruption to production. These include the complete rebuild of both drying plant electrostatic precipitators, the installation of a new electrostatic precipitator at the flash furnace, the conversion to a distributed control system throughout the smelter, and the installation of a converter air blowing control system.IntroductionBCL Limited operates a nickel-copper mine in northeastern Botswana approximately 100 km southwest of Francistown. Surface operations for the production of high-grade nickel-copper matte at a design capacity of 42 000 metric tonnes per annum, were commissioned in December 1973. Detailed descriptions of the mine and surface facilities have been presented previously(1-3).Over the years, a number of major engineering modifications and metallurgical projects have been carried out to overcome operating difficulties. improve metal recoveries, increase production rates and provide a better working environment.One of the major results of these projects was an increase in the 19805 in flash furnace feed capacity from 70 t/h to 120 t/h of new concentrate with a nominal feed rate of 105 t/h being achieved.(4)Because of the ore characteristics, i.e. a high mass fraction of ore reporting to concentrate, BCL operates one of the highest capacity spray drying plants and flash smelting furnaces in the world(5).A schematic of the BCL smelter is shown in Figure 1. The smelter is now in the seventh year of its fifth campaign, with the next shutdown scheduled for mid-l99S. In this campaign, the following major projects were completed:"

Jan 1, 1995

By L. Sun

Recently, micro-tubular solid oxide fuel cells (SOFCs) have attracted the attention of many researchers because of their numerous advantages over larger tubular and planar SOFCs. These include excellent thermal shock properties giving rapid startup/shutdown capability, a high volumetric power density compared to larger tubular SOFCs, and reduced sealing problem compared to planar SOFCs. In order to screen cathode materials for micro-tubular SOFCs, the perovskite cathodes were deposited, using a variety of methods, on 10.5 mol % yttria-stabilized zirconia (YSZ) tubes. Their electrochemical properties were then evaluated by using electrochemical impedance spectroscopy and steady-state polarization methods, based on a three electrode configuration, and with the reference electrode position carefully optimized. The oxygen reduction reaction kinetics at the cathode/electrolyte half cell were then investigated in detail.

Jan 1, 2005

By Md. Rashedul Islam

Magnetic data was collected from the Yeoju historical sites using the fluxgate gradiometer through six sites & several grids. We measured the vertical gradient by the FM256 Fluxgate gradiometer. The readings were logged every half meter. The obtained data were processed and treated to introduce a high quality magnetic image. The gradiometer results defined various positive and negative magnetic anomalies, which revealed the existence of several archaeological features of different shapes and sizes. The study of the process magnetic images give us a concept that the subsurface features are caved shape stone chamber tombs, burial mounds, deep room structure, Yeoju mausoleum, pagoda?s square foundation stones, walls etc. All these are superior work of early Goguryeo inheriting orthodox Silla style. So, the study area may have great archeological interest.

May 1, 2009

By Min-Sung Kang

Excavation and earthmoving equipment mostly operate in accident-prone areas. These areas normally have rollover, confinement, and fall or may be considered harmful work areas due to demolitions and sewage removals. It is inevitable that excavation and earthmoving systems should be developed to secure the safety of operators through unmanned and remote control systems. Therefore, this research proposes a system that enables excavators to be unmanned and remote controlled without any renovation, remodeling, change, or transformation by applying attachable and separable mechanism and modules. Moreover, this research proposes the sensor module to evaluate the dynamic status without processing remodeling or transformation the existing hydraulic drive excavation system by adopting the easy attachable and separable mechanism. The study verifies this proposal based on observed possibility and feasibility through the experiments.

Aug 1, 2013

By D. Newman

"This paper discusses the author’s work on international law norms of consultation with Indigenous communities and examines unexpected corporate stakeholder impacts on these norms. Customary international law, which governs the area, does not traditionally refer to corporate conduct. This paper surveys several sources on developing international law on consultation obligations; it also discusses the impacts these norms can have on corporate stakeholders in the mining industry. Finally, it asks how interactions of corporate stakeholders in this area can indirectly impact future law and suggests implications for different business models in the mining sector.RÉSUMÉ Le présent article traite du travail de l’auteur sur les normes de consultation avec les communautés autochtones contenues dans le droit international et examine les impacts inattendus des parties prenantes sur ces normes. Le droit coutumier international, qui gouverne ce domaine, ne réfère traditionnellement pas à la conduite des sociétés. L’article analyse plusieurs sources traitant du développement de nouvelles lois internationales sur l’obligation de consulter; il traite aussi des impacts que ces normes peuvent avoir sur les parties prenantes dans l’industrie minière. Finalement, il pose la question à savoir comment les interactions des parties prenantes dans ce domaine peuvent avoir un impact indirect sur les lois futures et il suggère des implications pour divers modèles d’affaires dans le secteur minier."

Jan 1, 2015

By Paul Graham

Presentation Focus ? What is LTUG / What do we do? ? History of LTUG ? Examples of Benefits from LTUG Participation ? Encourage Participation What is LTUG? ? An informal gathering of surface mining companies to discuss and work issues of common interest and to share information and best practices around large tires.

May 1, 2008

By Robert G. Boutilier

Mining companies in communities without other large employers often encounter dependent or defiant stakeholder attitudes, sometimes simultaneously. Less often they also see some slip into social dissipation or advance towards sustainable development. This paper presents a four-quadrant framework that shows how patterns of social capital foster these four reactions. The two dimensions defining the quadrants are the social capital levels (a) between the company and each stakeholder, and (b) among stakeholders themselves. Examples from the Antamina mine in Peru illustrate a social capital measurement system that can predict these reactions and help the community chart its path towards sustainable development.

May 1, 2006

By C. F. Gleeson

"I HAVE BEEN ASSIGNED the pleasant task of adding a last word in way of summary to this session. I think that the trend set in having a geochemical session at the CIM Annual General Meeting is a good one and I hope it will continue so that members of the mining fraternity can get together on a regular basis and discuss geochemical problems peculiar to our Canadian scene. A series of interesting papers have been presented on what has been considered by many in the past as not only a problem area for geochemistry but even an impossible one. The papers should help dispel some of these fears. Lack of development of geochemical techniques in the Shield has been due to a variety of factors, many of which have been mentioned. However, I feel that one of the main reasons for this lack of development has been timidness on behalf of many people to get out and do the necessary work which helps produce answers to many of the questions asked. New developments and applications of geochemical methods in the Shield will not be done by the faint of heart but by those who have the curiosity, interest, imagination, drive, resources and, most of all, the intestinal fortitude to stick to it and not give up because results or conditions do not meet with preconceived notions. Another element that will be needed by those who will successfully apply the techniques and who will be responsible for new breakthroughs is the systematic approach to sampling and analysis and the integration of geochemical, geological and geophysical results. Erratic sampling patterns - a sample here and a sample there - generally lead to more problems than solutions."

Jan 1, 1971

By R. A. L. Drew, F. Edelmann

Brazing is a low-cost process used extensively in the manufacturing and repair of aircraft gas turbine engines. Components within the compressor stage of the engine experience relatively low temperatures (600-700°C), therefore joints of stainless steels are typically employed. In such joints, a Pd-Ni-Cr-Si-B (PalNiCroTM) brazing alloy is used as a sealant, however brazing procedures are not well understood. The wetting behavior of PalNiCroTM on AISI 347 was evaluated with respect to contact angle. A microstructural evaluation was carried out with variable joint clearances. Microhardness profiles were performed to investigate the presence of hard secondary phases, which were later confirmed by electron microscopy. The results indicated an equilibrium contact angle of 10° within 100 seconds. The average microhardness of the braze layer and base metal were approximately 550 and 205 VHN, respectively. At the interface, a diffusion zone was present containing carbides and borides.

Jan 1, 2004

By F. Musuka, D. Jenkins, A. Keyes

BHP Olympic Dam operates a Direct-to-Blister copper flash smelting Furnace (DBF) and an Electric Slag Cleaning Furnace (ESCF). Tapping blister copper from these furnaces via tapholes is a routine task carried out by trained personnel. Blister tapping is a high-risk activity with personnel operating in close proximity to molten metal. BHP’s risk management framework has identified taphole integrity as key to managing the potential for loss of molten metal containment and molten metal – water steam explosion, both of which have the potential to cause multiple fatalities. As part of the focus on managing this risk, since 2017, a dedicated Taphole Development Team has been embedded in the operation to run an accelerated improvement program focused on safely and sustainably embedding an improved taphole design with greater integrity. The program of works includes selecting and testing of new materials as well as improving operating discipline by collaborating with tapping personnel to convert their knowledge into codified condition monitoring and operating strategies. Computational fluid dynamics (CFD) is being used to derive critical risk controls, and to develop live-alerts to infer excessive refractory insert wear. To date, improving DBF blister taphole mudgun clay has led to more consistent drilling depths and subsequently reduced oxygen lancing requirements, resulting in improvements in taphole insert service life. On the ESCF, insert performance testing and development of a new taphole condition monitoring strategy, is being used to increase taphole insert tonnages to more sustainable levels. Operations personnel have been closely involved in different phases of the change management, this has led to standardization of tapping practices for both furnaces, and improved ownership of the proposed changes. The paper discusses the maturity in taphole integrity risk management as a result of recent and ongoing developments. It then provides an overview of future taphole developments proposed at Olympic Dam. INTRODUCTION Tapping operations at Olympic Dam and learning from significant events The Direct-to-Blister furnace (DBF) at Olympic Dam was built with a conventional design blister taphole, which was designed for manual oxygen lancing and clay stopper bar plugging tapping operations (Campbell, 2005). Manual tapping is a high-risk activity, where personnel work in close proximity to molten metal, and molten metal personal protective clothing and equipment must be used. Opening tapholes by oxygen lancing is a skilled activity and unintentional damage to the taphole inserts can occur. Since 2008, a Mudgun and Drill unit has been developed and trialled and is now in use on the DBF blister tapholes, to remove personnel from the line of fire when opening and closing tapholes. This has the additional benefit of reducing lancing damage to taphole inserts. A new taphole design labelled the Modular Blister Taphole (MBTH) was developed at Olympic Dam for the Mudgun and Drill operation. The intent of the design was for mudgun clay to fill the entire tapping channel when plugging after a tap. The drill would then drill through this clay plug to open the taphole.

Jan 1, 2019