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The hydrometallurgical treatment of copper ores and concentrates continues to be an active field of innovation. The direct extraction of copper from ores containing chalcopyrite is an important development to provide an alternative to flotation-smelting and refining. Jetti Resources (with the University of British Columbia) and the JX Nippon Group have developed process options for chalcopyrite heap leaching. Biological heap leaching developments for chalcopyrite are also continuing in parallel. These direct leaching technologies are also very attractive for arsenical ores. The atmospheric leaching of copper concentrates is an attractive option along with autoclave processing. The Galvanox™ Process is the focus of commercialization by InCoR Galvanox Holdings under exclusive license by the University of British Columbia. The Galvanox™ Process can be used to treat chalcopyrite or enargite containing concentrates to high copper extraction with simultaneous precipitation of arsenic as atmospheric scorodite. FLSmidth has continued development of the Rapid Oxidative Leach (ROL) and associated technologies for chalcopyrite leaching. The Glencore Albion Copper Process using ultra fine grinding of copper concentrates and atmospheric leaching has found application in central Africa. The pressure leaching of copper concentrates continues to be attractive for rapid, complete oxidation of sulfide minerals with high copper extraction and arsenic stabilization of iron-arsenate minerals and precipitates. The Ecometales PLCC project is designed to use high temperature total pressure oxidation for treatment of an arsenical copper concentrate with use of existing copper SX-EW facilities for copper cathode production. The excess acid from the autoclave process will be used to make up the acid demand for associated copper ore heap and dump leaching operations. INTRODUCTION The recovery of copper from ores is dominated by the flotation of copper concentrates followed by smelting—converting and electrorefining. This process has been enabled by the development of froth flotation and progressively made more efficient by advances in smelting and converting technologies.

Jan 1, 2019

By Gordon Thompson

"Development of the unique Mine Games exhibition at Science World British Columbia is the largest ever collaboration of many interests to present the story of mining and the issues of mineral development delivered to the public by a science education centre.IntroductionMineral education programs have long been a major focus of the British Columbia mining community. Mine Games and its tremendous potential to enhance industries image and the public's awareness of mining is unequalled in the field of Issue Based Education Exhibits.The main goal of the exhibition is to look at the future of resource industries in a rapidly changing world of economic activities, new technologies, and growing public concern for the environment. Three challenges were the aim of the exhibition: to increase participation, to serve as a tool to increase interest in science and technology, and to draw an increasing number of school students to the interests of geology and the earth sciences. Mine Games is to serve as a meeting place for discussion of issues and where reliable information can be shared and new ideas explored.The exhibition is designed to develop new approaches to hands on learning that encourages visitors to explore and generate discussion and thinking with respect to resource development activities.The role of author, beginning in 1993, was, with senior industry leaders, to coordinate the raising of $1.3 million to complete the funding of the $1.6 million project total. The second and most interesting challenge was to work with the many minds that were collaborating to create the exhibition and to assure that the facts and science were correct. This involved the coordination of ""expert groups"" that verified the science and technology and the issues that the creative design team at Science World planned to use in development of each exhibit module."

Jan 1, 1995

By Victor Rudenno

"Previous methods have employed statistical analysis to model future mineral resources. The method presented in this paper uses Zipj's Law to determine the size and grade of tin deposits still to be discovered. The law is applied independently to both known deposit tonnage and grades. A probability distribution for both 'tonnage and grade is computed/or those deposits still to be located and then, by applying a correlation between tonnage and grade, a distribution of the probability of metal content discovery is obtained.By considering an economic cut-off in metal contained in a deposit, the probability of economic success for the next tin discovery is computed, both for a world discovery and for the special case of Tasmania, Australia. The results indicate a probability of 11-37% on a world-wide basis and 18% chance of economic success in Tasmania.IntroductionIn the past , most attempts to determine the probability of success in finding an economic mineral deposit have relied on the accumulation of statistical data. These data are then used to predict a suitable frequency distribution to assess the probability of finding a deposit of a given size and grade (Singer,1975).The method not only relies on one having sufficient data, but also on the assumption that the data are not biased and that the distribution (usually log-normal) is a correct one. The method presented in this paper, to analyze tin deposits, uses Zipf's Law, which has been recently applied to oil, uranium, lead-zinc and gold deposits by Folinsbee (1977) and to Western Australian gold deposits by Rowlands and Sampey (1977). Tapp and Koniuszko (1978) have applied Zipf's Law to mineral distribution patterns in the Northern Australian orogenic provinces, which has enabled them to make predictions with a relatively small data source."

Jan 1, 1981

By The Staff

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

Jan 1, 1942

By J. C. Kurnia

Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers? pneumoconiosis and silicosis. Major sources of dust appear of course along the mining face where the minerals are extracted. Proper control and management are required to ensure safe working environment in the mine. Presented here is the use of a computational fluid dynamic (CFD) approach to investigate the flow and dust behaviour in mining tunnels. The objective of this study is to propose and examine various strategies to mitigate dust dispersion from the mining face and reduce dust concentration to a safe level for the operator. In a companion study, the authors investigated various methods for mitigating dust dispersion from the mining face to ensure safe dust concentration levels in the mine tunnel. Among the examined methods, implementation of brattice to direct the flow from the main airway to the mining face is the most effective method to disperse dust particles away from the mining face. The installation of brattice, however, will limit the movement of mine operators and vehicles in the tunnel. Hence, application of a hybrid brattice which is a combination of a physical brattice along with suitable directed and located air curtains is proposed and examined. Based on the CFD simulation results, over a range of parameters of interest, it was found that the physical brattice blocks the ventilation air and directs it to the mine face while an air curtain located along the brattice outlet offers flexibility in keeping the dust away from the operator allowing more freedom for the operator and the equipment. Results of the modelling over a range of parameters of interest are presented and discussed with the goal of managing dust concentrations within safe limits for the operator.

Aug 1, 2013

By James A. Deeks

"Motor failures and equipment bearing failures are responsible for reduced productivity.With the introduction of computers and data acquisition systems, users are now able to monitor, report and trend deteriorating conditions and take corrective action before a critical shutdown occurs.This paper discusses the monitoring and trend analysis of' motors, and motor and equipment bearings. With today's digital electronics technology users are now able to monitor their equipment, detect deteriorating or abnormal conditions quickly, alarm the condition locally and or remotely, and decide if immediate corrective action is necessary or if it can be delayed until the end of a work Shift. All of this can be done long before any damage is done to the equipment.Monitoring Trend AnalysisIt is no longer necessary to compromise in selecting products, since state-of-the-art designs allow the adjustment in such small increments that the users are able to detect minute changes in a system's performance.Monitoring and trending of motors and equipment bearings is now available in economical packages which can be expanded as a system grows. Simply select the information you need, set the parameters, choose the scan time, and decide on the degree of reporting.Buffer storage of short-term monitoring of a number of analogue channels permit the user to view the recent history of motor data such as: motor average load, unbalance, motor current, ground fault, reserve thermal capacity, plus all of the settings of the protective device.A decision can be made to freeze the stored information after the motor stops or after the motor starts. Then the user is able to recall the conditions and diagnose the performance and the cause of the abnormal condition. Typical scan times range from ¼ second to 5 seconds ."

Jan 1, 1992

By Stephen G. Hardcastle

Worldwide, metal mines are going deeper. For example in Canada there are six such mechanized mines planning production at 3000m (10,000?). Working at such depths challenges all aspects of mining including the provision of ventilation to supply an equitable working climate for personnel and machinery. This paper explores the overall challenges of supplying ventilation in Canada?s deepest mines and how the volumes required could be minimized. This is essential because it must be remembered that ventilation and refrigeration are not only costly items to supply, but the magnitude of their cost is also very sensitive to the volume supplied. For ventilation this is obvious because of the cubic relationship between volume and cost. In deep mines, the main function of ventilation is the removal of heat transferred from the strata and generated by the mining machinery, and the air volumes supplied are designed accordingly. The second consideration is the removal of other pollutants that could be harmful to humans such as diesel and explosive fumes. However, the need for ventilation at its present design levels could be reduced. This paper discusses the implications of such technologies as: teleremote mining and alternatives to diesel equipment on the magnitude of the volume supplied; ventilation-on-demand which recognizes ventilation as a costly and limited resource; plus other aspects, such as the benefits of controlled recirculation, local cooling, and heat rejection back to the strata to gain further advantage from new developments. Furthermore, this paper advances the need to be able to design ventilation systems more cost effectively and how such new advances as process simulators can be used in conjunction with ventilation simulators to explore the diverse options that could affect the air volumes required and provide more realistic economic data upon which to base design decisions.

May 1, 2003

By Mitchell Gordon

"In almost all thickener applications the highest possible solid/liquid separation efficiency is what is desired by the user. There is a trend in the industry due to monetary restraints and environmental pressures to look at ways to extract this maximum performance by either retrofitting existing thickeners or installing the most cost effective new thickener. This paper looks at some of the common problem areas and presents a range of solutions developed by Outokumpu Mintec in North America and outokumpu's subsidiary Supaflo Technologies Pty. Ltd.The Emerging PictureAfter many hours of discussions with a large number of plant personnel over the last two years a picture began to emerge regarding current thickening operations in the industry. Initially, it seemed that everybody had their own unique process problems and therefore needed a correspondingly unique solution. Looking more closely at all the cases and the ideas that we had either implemented or suggested, it gradually became apparent that the majority of operators all had one and the same process need ....""Better Separation Efficiency""The range of operational problems that were uncovered in the survey were much more varied than expected and often were not even considered initially to be thickener problems. Often, it was only after the rejection of many solutions to the problem, generally due to capital cost, that the actual cause of the problem was looked at and found to be a thick-ener.A summary of the problems that have so far been identified is presented in Table 1. They are subdivided under three major categories of environmental, process and paste fill to highlight the wide range of mining activities that can be affected by poor thickener performance. These seem to be the major areas where the need for better separation efficiency is rooted."

Jan 1, 1995

By J. Drenda

The model for methane removal from the workings directly behind an advancing longwall as presented in this paper may be used for U-ventilated cross or length-wise systems of longwall advance, starting from the boundaries of the extraction field. In mines with high methane concentrations, Uventilated longwall extraction from the boundary of the extraction field produces a methane risk. The risk is manifested by a higher methane concentration at the end of the longwall, upper gate and incline. The methane in increasing concentrations, which is emitted mainly from the workings with caved areas, appears towards the end of the longwall and in the upper gate. The graphical model of the longwall provided includes both the workspace of the longwall and the caved area. Based upon a model of the rock distribution in the cave, a ventilation model comprising two standard air splits and large number of crosswise air splits has been constructed. Simulations indicate that if the shearer is not present in the longwall, the air distribution in the caved area is symmetrical. The presence of the shearer, both at the bottom and the top of the longwall, causes an asymmetrical air distribution in the cave, that is the asymmetrical flows in the goaf and longwall workspace and in the inflows and outflow between those regions. This phenomenon causes an increase in methane concentration at the end of the wall and at the upper gate. The methane removal method proposed for workings with a caved area directly behind the advancing U-ventilated longwall, starting from the boundary of the field, consists of the removal of methane-air mixtures from the caved area with the boom pipes. These booms may be of several meters long and may be extended if necessary. The insertion of the boom pipes into the cave towards the end of the longwall and connecting them with the general methane removal system creates negative pressure causing a change in the depression field, which is the aerodynamic potential field in the goaf area around the ends of the boom pipes. This will promote the extraction of the methane-air mixture from voids and the goaf cracks, and the area from which methane is being extracted may extend to the side of the cave. This is a positive phenomenon, which could result in the methane flow from the goaf into the airflow in the longwall workspace decreasing or even stopping. A reduction in the methane flow into the longwall workspace with extractions booms will be advantageous for the production continuity. Based on the floor load model for the rocks in the cave and the methane-removal boom load model, the value of the force required to move the boom behind the advancing wall has been calculated. Strength calculations for the pipe were performed using a finite elements method. The analysis results, as well as the comparison of the pipe material effort to the strength parameters of steel, which can serve as piping material (for the assumed load conditions), lead to a belief that the proposed boom construction satisfies the strength requirements.

Aug 1, 2013

By Charles Tkaczuk

Key issues ? Process control is a corporate function implemented locally. ? Security and documentation is mandatory requiring standard practices. ? Publish and communicate activities (do not re-invent the wheel). ? Payback metric system for all projects. ? Partnering with vendors based on experience, expertise and joint R&D. ? Focus on phased process control projects and distribution of costs. ? Integration of services and functions. ? Application of global standards. ? Big picture application thinking.

Apr 1, 2005

By A. Chieregato, C. G. Oñate Salazar, D. Martinelli, D. Peila, M. Barbero

This paper is aimed to confirm the possibility to excavate fractured rock masses by using EPB shields, even in presence of relevant water tables. This verification is based on laboratory test experiences carried out at TUSC laboratory of Politecnico di Torino, where the natural material is tested in order to verify the suitability of a certain conditioning technique in particular conditions. This is due to the fact that every case should be studied apart from existing studies on a certain rock type, as other factors such as fragmentation of the rock mass, natural water content and porosity of the rock can considerably influence the final result of the conditioning process. The most important aspects that allow to consider the conditioning of fractured rock masses as suitable are: possibility to create a plastic paste that can transmit the pressure at the front in a effective way; reduce the permeability of the spoil material in order to reduce the possibility of water leakage inside the chamber and eventually in the tunnel; verify the consistency of the conditioned material for the extraction through the screw conveyors and the belt conveyors. For this research an argillitic schistose rock mass, with some quartzitic and calcareous inclusions, has been studied by using different level of conditioning in order to verify the suitability of an eventual EPB excavation through this formation.

Jan 1, 2015

By John H. Fowler

"Barytes is one of the major components of drilling fluids used in oil and gas well-drilling. This mineral's close association with the petroleum industry bestows it with a commodity status not enjoyed by many other industrial minerals. Approximately 85% of world barytes production is used as a weighting agent in oil and gas well drilling while the remaining 15% is consumed mainly in the manufacture of barium chemicals, glass and as a pigment, filler or extender.Barytes mining began in Nova Scotia around 1865 and has continued until the present. Currently there are three barytes producers in the province one exporting pharmaceutical-grade barium sulphate and the other two supplying drilling mud-grade barytes to the offshore. Several barytes exploration and development programs are underway with excellent possibilities that Nova Scotia deposits will supply a significantly larger share of the drilling mud-grade barytes used in east coast drilling programs.Currently there is renewed interest in barytes activities in Nova Scotia because of its use as a weighting agent in drilling flu ids used in offshore oil and gas drilling programs.This paper reviews the use of barytes by the well drilling industry; outlines the history of barytes mining in the province, progressing to present-day exploration, development and production activities underway in Nova Scotia; and concludes with the market potential for Nova Scotia barytes."

Jan 1, 1986

By Nima Nabavi

Shovels and excavators have significant blind spots due to their large sizes, increasing the chances of collision with other surrounding equipment such as haul trucks, loaders, and dozers. While a camera surveillance system is very useful in preventing collision, it can benefit from two additional features: (i) the ability to display the distance of the closest object within the view, and more importantly (ii) the ability to warn the operator if objects are getting too close. After a comparison between few different technologies, it is explained how these features can be provided by integrating rugged pulsar radar sensors with a camera system. The specific radar technology is already field proven in the harsh mining environments. Motion Metrics International Corp. has developed this exact product, which combines its 4-camera surveillance system (ViewMetricsTM) with a series of rugged radar sensor elements, named ViewMetricsTM-Radar. The radar system employs intelligent CAN bus communication to reduce wiring, hence improving hardware reliability with built-in troubleshooting features. A USB connection is the only hardware bridge between the radar sensors and the embedded computer. As such, an existing ViewMetricsTM system can be easily upgraded to ViewMetricsTM-Radar. As addition of new interfaces to the cab could result in operator distraction, this paper explains how ViewMetricsTM-Radar reduces distraction compared to other radar collision prevention systems.

Oct 1, 2009

By Te Gao

It is a general expectancy that in most of the construction and renovation project, the contractor is going to hand over the as-built documents to the owner or the facility management team at the completion of the project. The main challenge for the handover process is to ensure the completeness of the captured building information and the accuracy of it in terms of how well it represents the reality. Building information models (BIMs) can be used as an information repository to store and deliver as-built information. However, due to changes made in the construction and renovation phases and errors made in the design and modeling phases, discrepancies can exist between BIMs created in the design phase (asdesigned BIMs) and actual building conditions. Laser scanning technology is able to efficiently capture accurate geometric information, which provides an opportunity to identify and quantify discrepancies and update as-designed BIMs into as-built BIMs. This paper presents a case study, within which the asdesigned BIM of a newly renovated research lab was updated into an as-built BIM using laser scanned data captured in the renovation phase. This paper introduces the challenges associated with the updating process for the as-designed BIM. In order to address these challenges, this paper introduces a framework that supports the update of an as-designed BIM by incorporating point clouds captured by the progressive laser scans.

Aug 1, 2013

By W. J. D. Stone

"INTRODUCTION Over the past decade, a number of publications have described the advances in High Intensity Wet Magnetic Separation. A number of significant, but small capacity installations were made and are successfully operating. These were followed some three years ago by larger installations treating ilmenite gravity concentrates; at least one machine treating 25 tons per hour of new feed was installed and is successfully operating.However, this still did not result in general acceptance that High Intensity Wet Magnetic Separation could be applied on a large scale. Neither did it dispel the feeling that High Intensity Wet Magnetic Separation was ""expensive"" and hence, confined to small scale – high value applications suchas the cleaning of tin concentrates. In addition, there is the usual reluctance of being the ""guinea pig"" which has resulted in waiting to see ""someone else"" make the first large installation decision. Such a decision and installation has now been made.Therefore, the purpose of this paper is to show that High Intensity Wet Magnetic Separation has been commercially accepted on a large scale and to show its general application to the base metal mineral industry.Examples are confined to a few specifics due to the large volume of preliminary test data that is available. The art has now reached the stage where much of the preliminary work should be taken through to serious evaluation."

Jan 1, 1971

By C. Sist, J. Shannon, J. Fossenier, J. F. Adams

With the cleanest and easiest to treat copper concentrates dwindling and becoming harder to find, electrorefineries must deal with the reality of higher impurity anodes. There are well-known strategies for managing nickel, bismuth, antimony, etc. using bleeds (Ni, Bi, Sb, As) or arsenic control (Bi, Sb) or hydrometallurgical add-on circuits (IX, MRT, SX for As, Bi, Sb). However, for integrated copper producers and those producing other base metals it is often worth considering a more holistic, global approach. This paper will discuss both the well-known strategies as well as some global strategies and the role that hydrometallurgy can play in them. Examples will include atmospheric and pressure leaching, selective precipitation and impurity recycling or fixation. INTRODUCTION In the electrorefining of copper, impure copper anodes are electrically corroded, and pure copper is deposited on cathodes by passing DC current through an acidic copper sulphate solution. The anode copper impurities either settle to the cell bottom as insoluble components (anode slimes) or remain in solution with minimal deposition at the cathodes when correct operating parameters are maintained. Consideration of impurities is important in all copper electrorefineries. A typical impure anode contains 98.5–99.5% copper (Schlesinger et al., 2011). Table 1 shows the range of impurities reported for all copper anodes in the 2007 survey of operating refineries (Moats et al., 2007). Also shown is an approximate “limit” of anode compositions within which the majority of refineries operate without additional impurity removal capacity (beyond conventional liberator/bleed circuits). The column is somewhat subjective and meant to be an approximation only since there are many factors that influence impurity deportments and refinery impurity tolerances. More recent world survey data from 2013 show the averages for all impurities trending upward from 2003 to 2013 (Moats et al., 2013). With a competitive market for good concentrate and more copper recycling from electronics (which contain high levels of impurities such as nickel, lead and antimony), this trend is expected to continue through the coming years. The traditional primary method of impurity control is refinery bleed through liberator cells which are employed in the vast majority of refineries (Moats et al., 2013). These are used to control copper (primary liberators), nickel, arsenic, antimony and bismuth (secondary and tertiary liberators). Other methods of impurity control include arsenic addition (upstream in the smelter deporting to anode or directly to electrolyte) to control antimony and bismuth (Kamath et al., 2003), ion exchange or molecular recognition technology (Hur et al., 2005; Navarro et al., 2012) for antimony and bismuth. Many refineries also operate nickel evaporators to remove nickel sulphate before recycling back acid. Some use, or are contemplating using, acid purification units to recycle acid and arsenic without nickel and making nickel carbonate (Kamath et al., 2003; Sheedy et al., 2006).

Jan 1, 2019

By D. Djokic

One of the most attractive features of electron beam curing as a process for manufacturing composite structures is the potential for attaining very low levels of residual stress as compared to thermal curing. This residual stress reduction is important both for the potential to reduce composite failure strains at low operating temperatures and the associated reduction in process-induced deformation. Previous work has demonstrated that it is possible in some cases to significantly reduce residual stress development during irradiation and also avoid development of additional residual stress during post cure. In this paper, simple L-shaped composite laminates were used to study the development of residual stress and deformation during thermal post-cure of specimens that were already partially cured using different radiation doses. Following post-cure, these specimens were also subjected to high-temperature loads to study creep behaviour under service conditions. Aerospace

Jan 1, 2006

By R. A. Kipp

THE dry concentration of ores and minerals is a subject on which there is very little engineering literature available. With the advent of flotation, practically all milling research was turned to this development as it held the answer to large-scale economic operations. However, there are many concentration problems that can be more adequately and economically handled by the dry methods that have been developed, and, consequently, I believe it is very advisable for mining men to become fully 'conversant with just what can be done in the dry state. Therefore, today, I should like to give a brief summary of the processes that are available and, in a general way, how they can be a p-p lied. I shall confine my remarks mainly to two dry processes: THE Am FLOTA'l'ION TABLE AND THE ELECTROSTATIC SEPARATOR Dry Magnetic Separators should probably also be included, but I am

Jan 1, 1961

By T. Winkler

This paper presents elements of the Virtual Working Environment for identification of hazards occurring in the mining industry. The Virtual Working Environment includes models of machinery and models of anthropometric features. Examples are given for identification of technical hazards at the design stage using the following computer programs: Finite Elements Method, Multibody System Analysis and Human Body Modeling. One of the methods to improve work safety at the machine and equipment maintenance stage is to share design and operational knowledge in a form of an Interactive Electronic Technical Manual (IETM). An IETM is created using so-called reusable knowledge elements connected by relationships. A metamodel created in Unified Modeling Language is one of the forms for description of these relationships. The metamodel can represent, for example, interrelations between elements of repair procedures. Examples of procedures realized during the replacement of a damaged cutting bit are presented and discussed.

Aug 1, 2013

By R. K. Singhal

"On the mining side the Canadian oil sands industry has become proficient in excavation and disposal of ore and overburden. Nearly twenty years of mining experience is now behind this industry. While local improvements to existing mining systems and practices will continue, it is believed that some further gains in productivity can be achieved by selectively introducing new ideas from other mining and non-mining industries. This type of technology transfer is vital for over-all cost-effective technology enhancement of oil sands mining operations.Discussed in this paper are the issues of mining equipment, equipment sizing, microprocessor and computer based technol¬ogy as applied to mine-wide data management, automation and remote control and a projection of likely mining systems in the year 2000!This paper reviews the ""state-of-the-art"" in selected surface mining systems and attempts to evaluate the forthcoming technology and its application."

Jan 1, 1989