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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 Christoph Mueller

?Globalization and the impact on mine operations? is one of the themes of the 2003 annual CIM meeting. Global mining business in practice always means to act with local base material resources in order to reach the mining company?s global business goals. On the other hand these operations are characterized by cost pressure and cycling product prices. Driven by actual prices, local product markets and local production cost, one time one mine can be most efficient while under different circumstances another mine will be the most efficient producer for the same customer [PENSWICK, 2001]. Therefor in the future the most profitable mining companies will be those who have permanent ?real-time? control on their actual production cost level. Certain approaches are under way to provide reliable modeling tools for aiding mining companies in highly complex decision finding procedures. A high potential for enhancing efficiency is the integration of all single steps of the mining working chain into a production process structure to make advantage of an optimized flow of material and information through the ?moving ore factory? [WIGDÉN, 2001]. Crucial to all these activities is the ability of getting reliable, just-in-time information from the entire mining production chain. As modern mining machinery today is controlled electronically and even already operated autonomously, the theoretical preconditions for the data acquisition is already fulfilled. But up to now, there was no way of cost effectively exchanging the process information with databases, simulation tools and other enterprise level software. Any data exchange problem had to be solved by individual and expensive software development projects. To solve these problems, the International Rock Excavation Data Exchange Standard (IREDES) was launched in 2000 by major players in the industry. The task of this initiative is to define a ?common electronic language? for easy and standardized data exchange between mining machines and central computer systems. As in other industries, this standard is expected to have significant impact on the use of automated equipment. It shall provide easy ways of using multi vendor machine installations in data controlled mining processes. At the same time it reduces cost for individual development of interfaces for all parties involved. The standard?s technical architecture is flexible and open - also for future applications. It uses modern technology enabling easy data exchange with commercial databases as well as open on line networking.

May 1, 2003

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 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 J. Koponen, K. S. Stadler, A. Fuerst, S. Gaulocher, Th. von Hoff, R. Veldsman

"Gearless mill drives (GMDs) are the workhorse in the mineral processing industries, more specifically when it comes to grinding crushed ore and cement (in various production stages) in semiautogenous (SAG) mills and large ball mills. They are renowned for their excellent reliability and robustness, long lifespan, and little need for maintenance, and thus yield a low total cost of ownership (TCO).A GMD represents a major investment for a mineral processing plant, and its availability is pivotal for the grinding process. As a basic rule, shut-down periods are to be minimized, but even much more important is that unscheduled shut-downs be avoided. In this contribution, we will present a portfolio of innovative remote diagnostic that consist of the following three key components:1. Trouble shooting is a form of corrective maintenance and is based on state-of-the art remote access technology, thus enabling highly skilled engineers to access the current sensor readings anytime and from anywhere in order to resolve urgent problems together with the GMD user.2. Periodic maintenance reports are a form of preventive and predictive maintenance and aim at continuous improvement based on long-term historical records and analyses of multiple measured signals. These detailed reports highlight the health and operational status of the GMD and are periodically (e.g. 3 months) submitted to the customer.3. Remote condition monitoring spans across preventive and predictive maintenance and is based on continuous recording and automatic analyses of relevant signals using advanced algorithms. The main issue is how to handle the enormous flood of data in an intelligent manner. The results of these analyses are made available to both the GMD user and supplier in real time in order to increase the availability and reliability of the GMD.In this paper, we consider various parts of the GMD, e.g. the cycloconverter, the ring motor, the auxiliary devices (e.g. cooling and lubrication systems), and also phenomena related to the mill itself (e.g. state and quantity of charge). The signal analysis techniques range from simple threshold-based analyses to complex time and frequency domain analyses. We will illustrate the benefits of the proposed approaches with some selected examples."

Jan 1, 2012

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 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 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 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. Royston

Reducing SAG Mill feed size has been a major trend in recent years. ‘Mine to mill’ strategies have reduced blasted-rock size, and in a growing number of operations reducing the primary crusher CSS and/or adding additional crushing upstream of the SAG mill have reduced rock feed size. While reducing feed size will increase SAG mill throughput, issues arise in terms of retaining charge in the mill, exposing the shell lining to impact damage, and maintaining milling performance should the pre-crush system shut down. This paper reviews the past experience on pre-crushing for SAG mills and provides an analysis of liner design (in particular grates and shell liners) for pre-crushed feed.

Jan 1, 2012

By Jian-bin Xie, Lin-fang Shen, Zhi-liang Wang

"In order to research temperature field for construction of connecting passage in Metro using artificial freezing method, the finite difference software FLAC3D is employed to numerically simulate construction process of connecting passage. During construction, the overall distribution of temperature field around connecting passage, the relationship between soil temperature and freezing time, the distribution and variation for the thickness of freezing wall are studied from the perspective of numerical analysis. The results show as follows: after 55 days’ freezing, the soil temperature surrounding connecting passage is about -24 oC ~ -28 oC, and the minimum thickness of freezing wall is about 4.0m, which is larger than the design value 3.1m. So construction conditions have satisfied to the excavation of connecting passage and pumping station. During the excavation of connecting passage, soil temperature has almost no obvious change and the thickness of freezing wall remains constant mainly. After 45 days’ normal thawing, the temperature of freezing wall rises 12 oC approximately. And the soil temperature rises faster at the beginning of the normal thawing stage. In the whole process of construction, the frozen area is about 5m outside the edge of connecting passage, and the cooling area is about 10m outside the edge of connecting passage. INTRODUCTIONThe first recorded application of the artificial freezing method is on a mineshaft project in 1862, and it has been widely used in foundation pit engineering, subway tunnels, mine shaft engineering and so on (Wang Zhiliang, 2010; Zhang Juanxia, 2012; Qiu Fan, 2007; Zhou Xiaomin, 1999). This method has many advantages of enhancing soil strength; decreasing permeability and adopting various unstable soils (silt clay, sand, gravel, etc.). It has been applied successfully in metro engineering construction in Beijing, Shanghai and Nanjing. According to incomplete statistics, the construction of connecting passage using artificial freezing method accounted for 98% in Shanghai metro (Qiu Fan, 2007)."

Jan 1, 2015

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 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 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 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 H. E. Lake

VERY EARLY in the initial stages of underground development work at Eldorado's Beaverlodge operation, the decision was made to use mill tailings as a backfill product. Mining and milling commenced in June, 1953, using locally available sand as backfill, while test work and installation of a plant was carried out to prepare ?and deliver the tailings to the mining areas. The first use of tailings was made in February, 1954, a sandslime separation being carried out with hydraulic cyclones. To date (January. 1956), approximately l 40,000 tons of fill have been used in the stoping areas, providing very effective support in a 50 deg. Vein system of cut-and-fill mining. The recoverable portion of the mill tailings amounts to 40 to 45 per cent, which has resulted in a product giving a percolation rate of 6 to 10 inches per hour. Owing to the fact that Eldorado has milled from 15 to 2 5 per cent more ore than it has mined, through the purchase of custom ore, the degree of control on the sand-slime separation has not been as critical as it might normally be when the filling operation must depend only on the tailings from ore mined. A description of the conditions involved and of the plant as finally installed is given below. It might be mentioned here that, with the impending increase in milling capacity from 700 tons to 2,000 tons p.er day, the present plant will be considerably altered within the ensuing year to handle the increased tonnage and distribution.

Jan 1, 1956

By Jehan Rondot

Les trois intrusions alcalines de Suzorite en haute Mauricie, bien que non datees, son! sans doute d ,attacher aU)( nombreuses autres intrusions alcalines dispersees sur les blocks Grenvillia et Laurentia et datees de I 050 Ma =t= 10%, done reliees d l'orogene grenvilien. L 'utilisations de la Suzorite est liee d sa forte proportion de phlogopite (>50%). Le rapport Mg/Fey varie de 3 d 7. Sa mineralogie et sa composition particulieres (forte proportion de Mg, Ket H20) en font son attrait.

Jan 1, 1984

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