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By Renaud Cousin

Supported gold catalysts were prepared by Direct Anionic Exchange on an alumina support and tested during the reaction of CO oxidation and of saturated and unsaturated hydrocarbons (C1 to C3). The catalysts showed high activies over a range of concentrations and temperatures compatible with an application to automotive exhaust cleaning. Furthermore, a complete resistance to thermal ageing at 600°C in the absence or presence of water was observed due to the obtention of strongly anchored nanosized gold particles during the preparation step.

Oct 1, 2003

By R. Liu

As Building Information Modeling (BIM) becomes widely adopted by the construction industry, it holds undeveloped possibilities for supporting Facility Management (FM). Some FM information systems on the market claim to address the needs for FM requirement. However, the question of whether the functionalities provided by the current BIM-based FM software companies are those actually required by the FM Professionals still need to be answered. The data is required by FM professionals in the operation and maintenance phases of facilities and type of maintainability problems that frequently occur, which can be solved early in design phase, have not yet been addressed. The aim of this paper is to clarify the frequently occurring maintainability problems and to investigate the potential areas that can use BIM technology to solve the maintenance problems in early the design phase. A survey was conducted to collect perspectives from the industry practitioners for the maintenance problems and their frequency. The survey results indicated that maintainability considerations should be taken into consideration during the facility design phase. The results also address the perceived areas by practitioners that need maintainability consideration in design phase.

Aug 1, 2013

By J. P. Norrie

The presence of copper-bearing rocks in the Coppermine River area of Arctic Canada has long been known. Word of this was probably circulated along the Arctic and Hudson Bay coasts by the Eskimo, who no doubt traded articles made from native copper among themselves. It is not known whether any of these ever reached the southern shores of Hudson bay. The Indians, also, knew of the occurrence of copper here, as they served as guides to Hearne when he made a successful trip over land from Hudson bay to the Coppermine river. The possible commercial importance of these copper deposits was early appreciated by the Hudson's Bay Company, who on December 7th, 1770, despatched Samuel Hearne from Fort Prince of Wales, now Fort Churchill, to investigate them. He reached the then unnamed river at a point forty miles from its mouth on July 14th, 1771, and after surveying the river to its mouth and naming it the Coppermine, he retraced his steps to Fort Churchill by an overland route. Hearne's expedition was probably the most remarkable and arduous ever attempted in Arctic exploration, but the actual value derived from the trip was entirely out of proportion with the hardships he must have suffered. He verified the occurrence of native copper, but his astronomical and other observations were of little value. Until 1912 no concerted effort was made to obtain any definite information as to the geology and economic value of the Copper-mine deposits.

Jan 1, 1931

By A. J. Basu

Air quality in underground mining operations can fluctuate significantly during the working day, but until recently the only way to ensure a mine had sufficient air quality was to over-ventilate and, with significant delay in adjusting the volume or direction of the airflow, working conditions were tolerable but rarely ideal. Underground ventilation management systems have been considered to achieve improved energy efficiency since at least 1995 in Canada. However, Mine Ventilation Optimization, (MVO) and integrating it with Ventilation on Demand (VOD) is only becoming more of a reality in the last seven (7) years. A systems approach to MVO takes into account all the elements from the point the power is distributed into the ventilation fans through to the actual quality and quantity of fresh air to the working face. Opportunities exist throughout the system for energy savings but not all of them are cost-effective. Depending on the application, these opportunities can be easily realized by properly sizing, streamlining, maintaining and operating the ventilation system using premium mine proven energy efficient components throughout. Implementation of VOD is a key step in achieving the MVO objective. However, VOD is a concept, and it requires various tools, procedures, and strategies for cost-effective and operationally viable implementations. This paper provides a historical background in the development of VOD and provides a framework for proper and cost effective implementation. In addition, an optimized ventilation system will also allow increased airflow by reducing resistances and shock losses. This turn in would allow production target improvement, which could be an attractive objective compared to energy savings. Mine ventilation is the life support system of an underground mine, and contributes to sustainable development and corporate social responsibility goals assuring health and safety aspects of strategic planning. The proposed framework addresses implementing mine ventilation optimization integrating ventilation on demand as a vehicle for energy, health and safety improvement and overall productivity gains in the mining cycle efficiency while significantly reducing carbon footprint of a mine.

Aug 1, 2013

By Alan L. Sangster

Auriferous, bedding-parallel veins occur in zones of carbonaceous, argillaceous and sulfidic turbidites in the Lower to Middle Cambrian sandy flysch of the Goldenville Formation. The 0348 values for vein and wall-rock arsenopyrite and pyrrhotite, and for regional pyrite and pyrrhotite, are highly positive. The values are similar to those from Cambro-Ordovician sediment-hosted deposits of other types, and display trends that increase upward in the stratigraphic sequence. The similarity in composition of vein and wallrock sulfides indicates a seawater-sulfate sourCe for sulfur, derived from the enclosing rocks at the time of vein formation. The upward increase in ?34S values is consistent with closed system sulfate reduction in the anoxic portion of a stratified water-colurnn. Published ? 13C and ? 18() values for Meguma Group vein carbonates are unlike those of other gold-vein carbonates, but are similar to those of diagenetic-metamorphic carbonates from the Meguma Group and elsewhere. These data indicate that the source for the vein-related sulfides and carbonates may be the host strata; possibly the arsenic and gold were derived from the same source.

Jan 1, 1992

By J. Paraszczak

Application of teleoperated and automated (or ?autonomous?) mobile equipment in underground metal mines represents a promising avenue for overcoming some of the challenges facing the industry. This paper addresses the overall effectiveness of autonomous loading and haulage equipment compared with conventional human-operated machines. Factors affecting availability, utilization, and production rate are explored, and an emphasis is placed on some problems and risks not present in conventional human-operated systems, as well as on the character and criticality of autonomous equipment. The need for a more in-depth analysis of factors affecting overall autonomous equipment effectiveness is stressed; these factors should be taken into consideration at the stage of feasibility studies. The paper concludes with recommendations and directions for future research.

Aug 1, 2010

By R. Mohamad, J. Asfahani

Abstract - Radioactive characteristics of pits drilled in the Al-Sharquieh mine while prospecting for recent phosphatic resources have been investigated. The results indicate that phosphatic layers are characterized generally by high radioactive intensities (more than 800 c.p.s). The lithological section in the study area is very complex sedimentologically, and characterized by high faciological variation in all directions. The Schlumberger geo-electrical configuration with fine separation of AB/2 was successfully applied to determine lithological boundaries, and the resistivities of the layers of the lithological section, especially for thin layers. It was shown that the phosphatic layer resistivities increase or decrease as a function of associated material. As a result, two types of phosphatic layers have been geo-electrically distinguished. The first is characterized by high resistivity and relatively low radioactivity, which could be related to the rock phosphatic layers. The second is characterized by low resistivities and high radioactivity, which could be related to the sandy phosphatic layers.

Jan 1, 2000

By M. C. Bétournay

? Prioritization of this research area identified through a CANMET-MMSL industry survey ? Possible technological breakthrough ? Prioritization of this research area identified through a CANMET-MMSL industry survey ? Possible technological breakthrough Disadvantages ? High cost and long time for equipment development ? Hard rock mining condition limitations ? Size of equipment ? Equipment set-up time, down time ? Performance does not meet financial return targets ? Ground control issues ? Drill and blast retains overall advantage

Feb 1, 2008

By D. Brossman

"The virtue of spray drying is that it is a drying method, and so far the only one by which it is possible in one operation to divide a mineral concentrate into its basic primary particles.,In so doing, each particle gets the same treatment and the result is a dry concentrate more homogeneous than any other known concentrate drying process. This is particularly good for a flash furnace requiring a bone dry finely divided feed. The spray dryer also features a very short residence time and due to the very quick operation the solids are kept cool thus preventing any risk of fire or explosions on these pyrophoric materials.There are many spray dryers now in operation in the mining industry and one of the latest applications is in South Africa where a spray dryer is treating a copper-nickel platinum concentrate which is, after drying, fed toan electric arc furnace. Experience has shown that the concentrate should contain 4% moisture for the furnace, and this is achieved by drying the concentrate bone dry and then back-mixing with thickener underflow pulp to provide an extremely homogeneous feed to the smelter. As mentioned before, mixing with pulp would be more of an advantage because we would not be evaporating water which would have to be added again afterwards.One of the first spray dryers to go in was at Western Mining Corporation in Kambalda in Western Australia. (A series of slides was then shown)."

Jan 1, 1972

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. G. Li

"A dynamic ventilation-modeling package, VREX, was used to simulate the mine activities through tracking the equipment movements in underground workings and determine the airflow demand for a new production scenario in a ventilation-on-demand (VOD) system. It incorporates the mine development data from a discrete event simulation and balances the ventilation network using the CANVENT ventilation solver. A case study was performed to demonstrate the capabilities of the software, evaluate the performance of the network and determine the potential energy savings for implementing VOD in a deep mine operation.INTRODUCTIONThe ventilation cost of an underground mine can be significant—up to 50% of the mine’s energy consumption could be used to run fans and provide heat/refrigeration to meet the specified production environment for workers and equipment. The VOD system has proven to be more efficient in operating the fans and supplying the amount of air corresponding to the mine activities taking place in underground workings (Hardcastle, Kocsis, & O’Connor, 2006). In order to properly solve and evaluate the VOD system, a dynamic ventilation modeling software VREX—the ventilation rules engine has been developed to simulate the mine activities and determine the airflow demand for each production scenario within an operation period (Dasys & Cameron, 2011).VREX is a decision support tool, backed by the CANVENT mine ventilation solver (Li, Kocsis, & Hardcastle, 2009), for determining the outcomes of network configuration changes over time. The software incorporates the mine development data with ventilation modeling through the discrete event simulation (DES) performed by SimMineTM. As it simulates the air requirements for different vehicles and activities, VREX can evaluate both the performance of the ventilation system and the potential economic benefits of making operational or technological changes (Pritchard, 2010). For example, the model can be used to assess the economic and environmental impacts arising from modifying regulations to support the use of electric or lower emission vehicles. The combination of DES and ventilation modeling provides a new technology to generate the production scenarios according to mine schedules and activities and to determine the potential benefits for various levels of ventilation control, such as time interval and work shift change."

Jan 1, 2019

By Malcolm Powell

"Predicting the performance of the whole mining process is surely the holy grail of predictive simulation. This can be named ‘Integrated Process Prediction’.The objective is to be able to predict the response of the processing chain, from mining to concentration, to changes in the ore type. This can apply to greenfields design – selecting processing options to optimise the overall mine performance within the constraints and aspirations of the greater community and environment; expansion and optimisation of existing plant to deal with changes in economic drivers and ore types; and on-line control – predictive reaction to ongoing changes in ore processing types in an operation.In order to achieve this there are several broad key components that are required: ore characteristics based on in-situ rock properties; a reliable 3D map of the ore body by the key processing parameters; prediction of how the rock fragments and the energy requirement to break it; the ability to predict and track progressive mineral liberation of the rock through the reduction process; the response of rock to separation processes as a function of the rock mineralogical properties. This requires the identification of primary rock properties and associating them with the rock particles as they move along the mining process chain to a concentrate or various forms of waste.This paper looks at the value of this integrated approach; the challenges it poses; the technology and capability we require; and how as a mineral processing community we can address the challenges."

Jan 1, 2016

"In today’s world of complex projects, where engineering and execution are supported by a high level of project management and systems, how critical is the human factor in design engineering. Based on his involvement on a variety of projects, Tony Lipiec will relate his experiences as the impact of 4 factors: the ‘team’ involved in the design and execution of the project; the project and information systems supporting the project; the impact of scope, time, and budget; and finally the selection of the proper success criteria to judge the project and the people who have enacted the project.The discussion of the team will relate to the quality of people and the impact of their knowledge, attitude and experience. It will also look at the relationships and interests of the various stakeholders. Decision making and taking responsibility will be discussed.Supporting the team are the management, document and information systems. The value that these systems bring to the project as a whole will be examined. How project size impacts the applicability of the systems will be discussed.Scope, time and budget are recognized as critical. Reference will be made to the interplay between these components which are vital to project success. The issue of iterative design and whether it is necessary will be considered together with the development of supporting technical information.Finally the selection of the proper success criteria and the awards provided to the team can have a big impact on the final, production success of the project. The author will discuss his views on the impacts of these on EPCM projects."

Jan 1, 2016

By C. Okay Aksoy

In Turkey, the increasing demand for lignite has necessitated an increased emphasis on both lignite production and recovery. This emphasis has resulted in a gradual increase in the application of the retreat longwall mining method for both its product recovery and productivity benefits. Also, in order to maximize the recovery of the natural resources and to increase total production, it is necessary to take advantage of underground reserve before abandoning the mine. This means that at the end of the life of the mine, the main drift safety pillar and the shaft pillar will generally be extracted. This investigation a preliminary study of the stability of the main drift and the shaft at the Hustas Mine as the safety pillars are extracted. In this study, field surveys belonging to the underground colliery of Hustas Co. in Soma have been investigated with the help of LAMODEL working under the Laminated Displacement Discontinuity principle for the models calibrated as a results of physical model and finite element analyses. The convenience of Laminated Displacement Discontinuity Analysis has been researched in such studies. The results out of the models have been coherent with the previous studies.

May 1, 2004

By Alan B. Morrow, William A. Poe

"Minerals processing operations are constantly challenged with improving production rates, yields, energy efficiency and process stability. Advanced Process Control has proven to be an effective tool for improving operations by capturing the full process capabilities consistently. However, the velocity of applying the technology as well as the sustainment of these significant benefits has been hampered by the usability of the software and adaptability of the applications.Some of the new technology developments that improve the usability and adaptability of advanced process control include:• modern and intuitive user interfaces,• customizable models to support unique process behavior,• fast and flexible OPC connection tools,• automated model building,• integration with first principles dynamic models and• improved performance monitoring.This paper will briefly discuss the new technology developments that have improved the usability and adaptability of advanced process control and how this can affect minerals processing operations.In today’s environment, Minerals Processing plant managers continuously face new challenges and requirements including:• higher energy efficiency,• increased run lengths,• reduced product quality variability,• reduced emissions,• higher availability, and• lower operating costsOperating a unit to meet these challenges in real time is not easy for operators and conventional process control systems. However, innovatively using existing technologies in Minerals Processing plants can improve operations on a minute by minute basis and reap significant benefits.Advanced Process Control (APC) can extract the maximum performance benefits from existing equipment while respecting plant operating constraints. Expensive capital projects to upgrade equipment are not always necessary. Advanced Process Control can deliver significant economic benefits by maintaining the plant at its most profitable point as conditions change."

Jan 1, 2016

By Jose A. Jimenez

"Mining operations generate an enormous amount of data that is difficult to organize, analyze and act on. These data require an extremely broad range of experts to investigate and manage the cross-disciplinary information. The data collects in paper files, diverse databases, historians, stand-alone applications, and excel files. This collection of sources represents everything from monthly, weekly, or daily inputs to real-time feeds or sporadic unscheduled entries. With the operational complexities ever increasing and fewer engineers per mine, an efficient operation is becoming more and more challenging. Engineers are typically burdened with data collection, clean up, and administrative efforts leaving very limited time for engineering assessment and/or optimization analysis. Often optimization becomes limited to the analysis of equipment uptime through existing field automation systems. A great portion of the field data is tucked away in historians seldom reaching those engineers who might leverage the data. Few mine operators have the time or budget to re-architect their operations data collection or management practice, so solutions must enable improvements without requiring expensive or time-consuming implementation. This presentation highlights examples where the aforementioned challenges are addressed using a solution framework designed to enable: 1) data integration and connectivity, 2) monitoring and opportunity recognition, and 3) engineering workflow automation. The initiative extends the concepts and success proven in the automation market segment to all disciplines across the mine operations. INTRODUCTIONThe mining industry by its very nature spends a great deal of its capital on equipment maintenance and replacement. In addition, periodic shutdowns due to equipment failure are typically very costly in terms of interrupted operations. Keeping mining equipment running at peak performance and avoiding costly shutdowns can make a huge difference in the overall return from mining operations. Today, information can be make available that can go a long way towards spotting equipment issues and permitting timely intervention to avoid costly unplanned shutdowns. That said, gathering all of the information from numerous points on many different pieces of equipment necessary to enhance overall equipment effectiveness presents its own daunting issues."

Jan 1, 2016

By Peter D. Cunningham

At Vale Inco in Sudbury, underground mobile equipment production and maintenance data is presently collected manually from paper slips. This paper reviews a pilot project that developed a system to electronically collect that data. The benefits and improvements in data accuracy, timeliness and reduction in collection effort, will be discussed. Technological issues that arose from the use of WiFi, RFID (Radio Frequency Identification) and the IREDES mine data equipment standard are also discussed.

Oct 1, 2009

By R. T. Seaman

There are several hydrometallurgical alternative processing options under development for high enargite and arsenic containing copper concentrates ranging from biological, atmospheric, medium temperature oxidation to total oxidative leaching. The most developed of these options is the CESL process boasting pilot campaigns totaling more than 8760 hours of fully integrated continuous operation, as well as, over two thousand batch scale oxidation tests performed on dozens of concentrates for flowsheet development. This paper reports the observed deportment of arsenic under varying arsenic, iron and acid oxidation conditions; it also describes the impact of iron to arsenic ratios and residue recycle on overall arsenic behavior and its stability in residue. INTRODUCTION The CESL Hydrometallurgical Process (CESL) was originally developed to compete with smelting of clean chalcopyrite concentrates. High Treatment Charges and Refining Charges (TC/RCs) combined with premiums on London Metal Exchange (LME) grade copper from onsite refining made treatment of copper concentrates using CESL a viable option at the time. As world demand for copper increased and a subsidized Chinese refining market developed, smelting contracts became more favourable for the miner and focus was placed on modifying the CESL Hydrometallurgical Process to handle concentrates with elevated deleterious elements. Dozens of pilot campaigns processing concentrates containing elevated concentrations of uranium, fluoride, mercury and nickel all led to further developments of the CESL Hydrometallurgical Process. In 2016 a United States patent was granted for a novel modification of the CESL Hydrometallurgical Process for recovery of copper from arsenic-bearing and/or antimony-bearing copper sulphide concentrates, Henry Salomon de Friedberg (2016). To date, over 2000 bench scale tests along with five fully integrated closed loop pilot campaigns, totaling over a year of online operation time, have been conducted processing arsenic bearing copper concentrates. This paper summarizes the observed behavior of arsenic under varying autoclave and process conditions.

Jan 1, 2019

By J. C. Ingles

"A survey of possible methods for controlling cyanide concentration indicated that the simplest method would involve the use of a potentiometric technique. Such a method was suggested by a paper from the laboratory of Mines Safety Appliances, which described a method for determining hydrogen cyanide in air. In this application, the cyanide was absorbed in caustic and a silver electrode immersed in the caustic solution provided a measure of the cyanide concentration. However, our attempts to use the silver electrode in this simple manner to measure the cyanide concentration of solutions were not very successful. A study of the mechanism by which a silver electrode responds to cyanide concentration made it evident why this simple procedure is not satisfactory.Basically, the silver electrode provides an indication of the free silver ion concentration of a solution, and generally speaking, ignores the other ions' present. It can be used to measure an anion if this anion complexes silver. This technique has been used in complexing studies to determine the activities of such anions as acetate, citrate, oxalate and chloride. To do this, the electrode has to be placed in a solution which initially contains a known concentration of free silver ions. Addition of the complexing anion causes a drop in the free silver ion concentration and hence a change in the potential of the silver electrode. The change in potential can be expressed in terms of the concentration of the complexing anion, and used to indicate its concentration in the solution being analysed. The determination of chloride-ion by a silver-silver chloride electrode is an example of an application of this technique. The solubility of the silver chloride with which the electrode is coated provides the initial free silver-ion concentration. Depression of this free silver-ion concentration by the presence of the excess chloride ion of the sample solution results in a change in the potential of the electrode which is proportional to the chloride-ion concentration."

Jan 1, 1965

By David Forrester

"At the 95th CIM Annual General Meeting in Calgary, 1993, a paper entitled “Progress on Futuristic Mining Technologies” was presented(Matthews and Sarin), in which they outlined the goal of continuous excavation of hard rock and some of the technologies being developed to achieve it. The subject continues to be featured in periodic reviews and articles in the literature, (Gertsch, 1994; E&MJ, 1995). Matthews and Sarin note the considerable success of the development and application of continuous mining technologies in the soft rock under-ground mining industry, especially those in coal and potash, with major benefit to overall production, productivity and economic viability. It is the belief that similar achievements can be realised in the underground hard rock mining which continues to drive the development of hardrock continuous mining technology.This overview has been prepared specifically for this issue of the CIM Bulletin. It attempts to tie together current advancements in continuous mining in soft rock (where remote control and automation are already well established) with the background and status of development in hard rock continuous mining. Following a brief review of key factors and machine types, soft rock aspects are discussed, then a more detailed review is given of hard rock technology, with particular reference to Canada’s HRDK Mining Research Ltd. and their key role.The mining industry has long been at the forefront of technology development, for example, the application of the early steam engine to reach reserves at greater depth for dewatering mines in the industrial revolution. By necessity, the individual characteristics of seams and orebodies dictate the mining method, continually presenting mining engineers with new challenges. One of these is the extraction process itself and the goal of replacement of the drill-blast-muck cycle by continuous excavation. Very soft rocks have always been mineable using some form of cutting, even with primative tools. However, as the challenge has been taken up, technologies have evolved to steadily increase the hardness of rock that can be mechanically excavated. It may surprise some readers that at least three machines have successfully cut and loaded rock with an unconfined compressive strength (UCS) of 250 Mpa to 300 MPa (36 000 to 43 500 psi) in field trials (Table 1)."

Jan 1, 1996