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By A M. Ebbels

"Underground mine scheduling decision-making has been based on production requirements, equipment productivities and the mine planner’s instincts on the best scheduling strategy for the mine to optimise the net present value (NPV) of a project.In the last few years, innovative software has been developed to optimise underground schedules based on NPV. The schedule optimisation tool (SOT) allows the user to set up scenarios based on grade, metal content, capital and operating costs.This paper discusses the results of two case studies undertaken using the SOT software to optimise the NPV of the projects.In each case study, the SOT software has been applied in two ways:using the original mine planner’s scenario and determining whether the NPV could be improved by changing resource capacitieschanging the scheduling goals to determine whether a different mining strategy would have a better NPV outcome.The outcomes of the case studies demonstrate that the mine layout and design were contributing factors to the overall improvement of the NPV and that SOT has a more noticeable impact on the NPV of projects where less sequence constraints are required, such as geotechnical sequencing and access development.CITATION:Ebbels, A M, 2016. Optimising underground mining strategies, in Proceedings Project Evaluation 2016, pp 60–65 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By T. Dunn

FMC Corporation has achieved a significant cost reduction through a new proprietary solution mining and processing technology at its Green River, Wyoming Soda Ash Facility. In the first phase, completed in October 1995, trona ore is dissolved, recovered and processed with the new technology, and then fed into an existing refining plant, replacing dry mined and calcined trona ore. The second phase, completed in April 1996, produced a fmal high purity product and increased capacity by 635,000 t/a (700,000 tpy). Both phases were completed under budget and well ahead of schedule.

Jan 1, 1998

By A. Dave Mackintosh

Historical closure data has provided a description of the stress distribution patterns occurring around mine openings and enabled the development of a time ? distance plot predicting the location of the stress peak and its migration away from mine openings with time. Data collected from active mining areas during the 1970?s and 1980?s indicated the peak appeared to stabilize approximately 135m (450 ft.) from openings after four years. The region of high load and accompanying poor ground conditions in which the peak was centred was spread over approximately 45m (150 ft.) to 60m (200 ft.). Recent data from new development headings cut adjacent to 25 year old extraction areas suggests load transfer takes place over a much greater distance and time frame than predicted.

May 1, 2001

By Jr. Wilkinson

In today's work environment a tremendous amount of data is required to provide the regulatory agencies justification to issue a mining permit. The demands for data, specifically environmental characterization data, grow and the mine plans must address the issues raised by the interpretation of that data. Computers and computer software can provide operators and consultants with the tools necessary to assimilate, digest and interpret these seemingly unmanageable data sets. This paper presents some examples of how Mincom's MineScape software can be applied to the task of developing coal mine permits in an electronic format.

Jan 1, 1996

By Stuart Marsland

"Reference materials have always been important for validating and controlling analytical methods', They have recently become even more important as quality requirements have become more stringent and customer demands for properly verified and controlled results increase. Clients, especially from the resource exploration industry demand critical validation of all results reported. Mintek has been producing geological and semi processed ore references since the early 1970's and recently due to increase in demand other manufactures have entered the South African Market.This paper describes Analytical challenges from the customer's perspective. The customer being the metallurgist, mine geologist, environmental scientist and geologists from resource companies. Reference Materials and their appropriate use and good understanding of them can aid greatly in building confidence in the results, choosing the right Laboratory for a project, deciding which set of results arc correct and providing evidence to the customer's clients that the results obtained are the very best possible.Throughout the world there are hundreds of reference materials produced by over 80 organisations and these are mainly ores, rocks, semi processed ores, metals, and many more. Mintek is one of the top 10 producers with over 75 products. Many of these producers including Mintek and their respective standards organisations belong to the ISO REMCO committee and their respective work groups. This committee's main task is to draw up guide lines for the use, manufacturing and certifying reference materials. In South Africa a mirror committee has recently had its inaugural meeting the function is to give clear mandate to the South African representative on the main ISO REMCO committee, the South African delegate bas an opportunity to influence the contents of the guides.Tile SARM program has since the year 2000 increased its sale three fold, the question is why? There is more accountability needed in our world. That means Analytical results have to be the very best possible and risks associated to them must be well quantified. Consider that the risk of wrong results of wrong decisions made from a result is trivial to laboratory, in comparison to the laboratories customers. The consequence to a laboratory could be a loss of income or some one may lose their job. To the customer he may dig up 1000 of ton's of rock with nothing in it or worse still don't mine it when the grade is high enough. This is seriol1s money."

Jan 1, 2014

By Robert Hopler

On June 13, 1912, the final decree of dissolution of the DuPont explosives trust was handed down, and the resulting new companies began operating at the beginning of the new year. The property assets granted to (or retained by) the companies were as follows:

Jan 1, 2014

By William R. Barton

The domestic portland cement industry consumes more than 12 million tons annually of raw materials chemically similar to fly ash. How these materials are used and how fly ash can serve in their place are discussed. Factors influencing whether or not a particular plant will use fly ash in place of an alternate material are discussed.

Jan 1, 1968

By D. Donison

The practice of blasthole mining is typically applied in competent ground conditions, primarily because of the open stope dimensions. At Magma Copper -Superior Mine, a field pilot project was completed examining a variation of blasthole mining in poor ground conditions. The results were very encouraging not only from a technical viewpoint, but also productivity viewpoints. This paper describes the pilot project and the resulting implications.

Jan 1, 1994

By M A. Tuck

Air blasts or wind blasts as they are termed in underground coal mining, occur in a number of types of underground mining where a void develops and the overlying or adjacent rock fails rapidly to allow the development of a high pressure air pulse. The effects of air blast vary widely from very low consequence to high consequence events causing multiple fatalities as occurred at North Parkes mine. The aim of this paper is to examine the phenomena of air blasts and the underlying parameters which determine the severity of the air blast event. A basic model under development is then detailed. The aim of the model is to determine the magnitude of the pressure pulse(s) developed during an air blast event. This, combined with a transient ventilation network analysis model will enable the airflows and associated pressure drops to be determined and allow the pressure pulse around the mine to be evaluated. The overall aim is to allow mining engineers and mine ventilation engineers to undertake a risk assessment of air blasts at individual mine sites, allowing working parameters to be changed to eliminate or reduce air blasts, or engineering controls to be developed to reduce the effects of air blasts.CITATION:Tuck, M A, 2013. Determining the pressure pulse for an air blast, in Proceedings The Australian Mine Ventilation Conference , pp 103-106 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By J. Ander

About fifteen years age some mines in western Canada commenced using Diesel engines, partly for development work but also for operations on quite a large scale. In the Eastern mining field, the Diesel engine made its appearance some eight years ago and has since, at quite a number of mining plants, proved to be a reliable and economical prime mover. As a result, it is today used more extensively than could have been foreseen only a few years ago, and it is reasonably safe to predict that the next few years will see the Diesel engine utilized to a still greater extent in the Canadian mining industry. It is not much more than thirty years since the first Diesel engine was put in operation. During the early years of this century, the Diesel engine took, so to say, its first faltering steps in public service. Since then it has reached a high state of perfection, and its importance has grown in a most remarkable way, until today it is used in practically every field where power is required. It is slowly but surely superceding steam for a great many purposes, as, for instance, for ship propulsion. While in 1921 only about 8 per cent of all tonnage launched was motor-driven, the proportion had grown to 38 per cent in 1927, and for 1929 it was slightly over 45 per cent. Some of the finest passenger liners afloat are Diesel-driven. In the early days, Diesel engines were built only in comparatively small units. Today engines with a capacity per unit of up to 10,000 horsepower, or even more, are being built for marine and stationary purposes.

Jan 1, 1930

By Saeed Zhandi, Behdeen Oraee

"Rock bursts remain an important problem in longwall coal mining. These bursts are due to a sudden and severe failure of rocks from a high stress concentration in deep underground excavations that occur with the instantaneous release of strain energy stored in the rocks. They can potentially cause irrecoverable damage to equipment and personnel, thus accurate rock burst prediction and control is expected to be carried out by the mine design engineer. As a result, this can constitute major challenges for said engineer. In this paper, forensic engineering has been used to evaluate the possibility and extent of rock bursts in deep coal mining. For this purpose, established mining engineering principles, including factors influencing the severity of rock bursts, have been incorporated in the forensic engineering technique. The analyses took place in five steps:• Assessment of regional and local conditions prior to the event• Assessment of conditions after the event• Hypothesize plausible ways in which pre-event conditions can become post-event ones• Search for evidence that either denies or supports various hypotheses• Apply engineering knowledge to relate the various facts and evidence into a cohesive scenario of how the event may have occurred.The paper concludes by demonstrating a method for predicting rock bursts and preventing their reoccurrence. The methodology used in this paper, together with the results obtained, can serve as useful tools for the coal mine design engineer in the primary evaluation of rock burst potential in underground coal mines.INTRODUCTIONA rock burst is defined as the sudden and great failure of rocks due to a high stress concentration in deep underground mines. This phenomenon occurs with the instantaneous release of strain energy that is stored in the rocks, and can cause irrecoverable damages to both equipment and personnel (see Figure 1). Rock bursts pose a hazard owing to their lake of predictability; in fact, research into understanding rock burst mechanics and implementing techniques for their monitoring and prediction has been taking place for over 50 years."

Jan 1, 2015

By Richard D. Moffett

The MineSight® Implicit Modeler arms geologists, engineers and surveyors with a better approach to 3D modeling. Use the tool to quickly retrieve a 3D wireframe from drillhole data and onscreen interpretation. Generate faster and more informed decisions to guide future work and improve reproducibility of results. Implicit Modeling is a mathematical surface fitting method that interpolates points to give a smooth and realistic fit. Control results by mixing planar, sectional and non-orthogonal polygons or polylines, as well as drillhole information to create solids or surfaces. The outcomes are particularly valuable to identify ore body trends, generate 3D contours of drillhole intercepts, or produce cut-off 3D maps. MineSight Implicit Modeler (MSIM) is fully integrated in MineSight?s robust and versatile suite of products, allowing you to interpret, interpolate and calculate while moving between applications. It connects seamlessly with the MineSight Torque SQL database, offering access to extensive filtering options. MSIM makes modeling much faster, allowing geologists more time to analyze data and test theories. The presentation will reveal how MSIM complements MineSight?s geomodeling workflow.

May 1, 2013

By Carol A. Pilon

"IntroductionRECENTLY, the Saskatchewan Research Council (Saskatoon ) marked the completion of one of its coal-related projects with the publication of the Bibliography and Index of Coal in Saskatchewan and Adjoining Provinces and States, hereafter referred to as the Bibliography and Index of Coal. Over a two-year time period, literature was surveyed and indexed and bibliographic data were compiled using a computer-assisted information retrieval system called FAMULUS. The final publication contains 1150 bibliographic references, which are cross-referenced by six indices.The project was initiated in September 1974, in support of Saskatchewan's Coal Resources Evaluation Program , an ongoing research program sponsored by the Department of Energy, Mines and Resources (Ottawa) and the Province of Saskatchewan. This program places emphasis on such areas of concern as the occurrence of deposits, chemical and physical properties, calculation of reserves and computer-assisted applications for the evaluation of lignite resources in the Province. Attention is also given to aspects of geophysical exploration, mining conditions and economics, by-products and the transporting of lignite. These are the subject areas .covered by the Bibliography and Index of Coal.The over -all objectives of the literature indexing project may be enumerated as follows: (1) to build a specialized resource library by surveying established public and specialized libraries, and commercial data bases; (2) to enter library data into the FAMULUS information retrieval system, to be used to generate bibliographies and indexes, and to retrieve information by the use of specified searching techniques; (3) to make this library data available to interested persons."

Jan 1, 1977

By K. Noda

Tamano Smelter of Hibi Kyodo Smelting Co., Ltd. started its operation adopting the Flash Smelting Furnace with Furnace Electrodes (FSFE). Thereafter, it developed a coke combustion technology based on C() concentration control, which made possible a low cost and high productivity operation without using electrodes. However, increase of treated concentrates and upgrading of matte grade for production expansion started to cause difficulties in operation control with then existing operation control system. This paper outlines recent improvements for stable operation of the Tamano Type Flash Smelting Furnace (T-FSF), such as computer aided operation guide system.

Jan 1, 2001

By DuPont Magazine

RBH Note: as stated many times in these articles, frozen dynamite was one of the greatest hazards facing the blaster. It wasn’t until the late 1920s that it was solved for good, with the introduction of nitrated ethylene glycol as a partial replacement for nitroglycerin in dynamites. The du Pont low freezing dynamites contained TNT, DNT, or nitro-substitution compounds of various sorts.

Jan 1, 2015

By K. Bommer

"In today’s fast paced, globally competitive world, reliability and machine uptime are of the utmost importance to a successful operation. Along with these targets more emphasis is being put on cost reduction and decreasing the environmental impact of the overall system. To achieve these goals, automatic lubricators and lubrication systems have been used in many industries for years and are now becoming a common tool in the mining industry as well. These systems are able to provide proper lubrication amounts at the proper times autonomously, helping to keep the machines running smoothly while minimizing the physical support required. Copper mines in the southwest have begun utilizing auto lubrication to avoid mistakes and unplanned shut downs on critical equipment. This paper will describe the engineering behind these products and review case histories where these tools have been successfully utilized in the mining industry. INTRODUCTION In a dirty, dusty, wet environment, where machine uptime is imperative, proper lubrication of bearings is the only way to survive. With the push for cost reduction and mines striving to lower their environmental impact and increase worker safety according to MSHA guidelines, the old lubrication practices have come under scrutiny. It is no longer encouraged or cost effective to have maintenance personal walk from point to point throughout the entire mine pumping a shot of grease into each bearing once per shift. Automatic lubricators and lubrication systems have been on the market for years but recently, as the market focus has changed and technology has developed, the use of these systems has begun to rise in the mining industry. Automatic lubrication systems can be as simple as a single point lubricator lubricating one (1) bearing or a more complex system lubricating numerous bearings. With system design, the automatic lubricator provides a preset amount of grease to a bearing at regular, predetermined intervals. The systems designed to lubricate more than one bearing contain grease pumps of some design and possibly PLC controllers which can be used to remotely adjust and monitor the system. As can be seen in Figure 1, the right amount of lubrication can be achieved much more reliably with automatic lubricators. Depending on application needs, the market now has products to fit almost every wish list. This paper is going to focus on the single point systems that are lower in cost but are still being effective."

Jan 1, 2015

By Stewart W. Daniel

"Increasing labour costs, the trend to larger mills, the processing of lower grade ores and a diminishing sup-ply of well-trained and experienced mill operators contribute to the necessity of automating a grinding circuit. With sophisticated process control techniques, supervision of the mill line is reduced to an occasional inspection by the shift supervisor. Process operating decisions and/or adjustments are quickly and accurately performed by the electronic devices to be described. When the variables in the grinding circuit are stabilized using the sensors and controllers as discussed, the over-all grinding circuit is maintained at its optimum grinding load level, with ample protection against under-and overloading."

Jan 1, 1967

By Mario H. Castro-Cedeno

"A design for a handheld MEMS chemical detector is proposed. The detector will be used to detect trace amounts of chemicals in air. It can detect drugs, toxic chemicals and/or explosives. The proposed detector will use ion mobility spectrometry (IMS), a technique that is well known for accuracy and has been used in the past in suitcase sized chemical detectors. The separation and detection of the chemicals occurs in the drift channel and the process was modeled using the finite element method and CoventorWare modeling software. A manufacturing process sequence for the drift channel is proposed and was demonstrated.IntroductionThe goal of this effort is to design, mode~ and prototype a MEMS chip that will be the key component in an ion mobility spectrometer (IMS). This technique uses and asymmetric potential to separate the various ion species in a stream of incoming air [1-4]. One advantage of IMS is its ability to separate chemical species from air at atmospheric pressure and temperature. This is a requirement for a simple to use handheld drug or chemical detector. IMS can be used to detect drugs, toxic chemicals and explosives and it is well known for accuracy in detecting very small amounts of chemicals. This chemical detection technique has been used in the past, but not in handheld detectors.One variant of IMS is the high-field asymmetric waveform ion mobility spectrometry or FAIMS [3]. The FAIMS process, shown in Figure l, works as follows: a gas sample is admitted into the instrument where gas molecules are ionized, typically by a weak radioactive isotope source, ultraviolet light source; and more recently through field emission. The ions move along the length of a channel while they are separated in the transverse direction by an asymmetric electrical potential. The potential, in the form of an asymmetric waveform, causes relative motion between the various chemical species. The species that hit the charged top and bottom plates are neutralized and only those ions that move along the center are detectable as charged chemical ions at the end of the channel."

Jan 1, 2004

This paper discusses current workforce demand projections for mineral processing engineers and emerging trends in mineral processing education. Attempts are made to identify gaps that often result in a mismatch between skills taught and skills needed by the practicing engineer. Clear examples of this include a less than uniform training in chemical aspects of mineral processing, and an understanding of the statistical and experimental design tools necessary to tame the often-large variation in operational parameters and plant data. The end goal is an educational system modernized to prepare mineral processing specialists for productive careers in the sustainable development of natural resources. A framework for revamping education based on an integrated modular approach is also presented. Keywords: mineral education trends, mineral processing programs

Sep 1, 2012

"Chairman: Professor J. de V. Lambrechts Rapporteur: Mr R. HempPapers:Computer-aided design of a flash smelting installation by M. A. T. Cocquerel, R. T. Gates and L. A. GreenPlanning of mine ventilation by E. U. Reuther and A. DohrnenCoal mine ventilation systems in the U.S.A. by R. Stefanko and R. V. Ramani Heat flow models in ventilation planning by A. J. Dickson and A. M. StarfieldThe first of the papers in the session dealt with a flash smelter installation, while the remaining three papers dealt with mine ventilation. In view of this the Chairman proposed that the paper on flash smelting be introduced and discussed first, after which the remaining three papers would be introduced followed by discussion on all three.Dr Cocquerel, who presented the first paper, used some typical flow diagrams to illustrate the process and stated that the program considered only steady-state operations and did not take into account the dynamical changes. Subjective judgment was necessary for the preparation of input data and some degree of user appreciation was required.Dr Cocquerel said that no work bad yet been done on an optimization program, but that this was being considered. Such a program would require a large amount of physical and chemical data which were not yet available. The variables to be optimized were the energy and material consumptions and the loss of metal in the slag.The Chairman opened the discussion by asking Dr Cocquerel if he could give a brief description of the flash smelting process for the benefit of those not familiar with the subject. Dr Coquerel replied that in the Outokumpu process con¬centrates were injected directly into the furnace, and that the process was somewhat analogous to flash distillation or evaporation processes, but was perhaps closer to the burning of pulverized fuel.The process had two distinct advantages. First, the heat evolved in the smelting reaction was used to heat the furnace, which resulted in less fuel consumption, and, second, the effluent gases were cheaper to treat than the effluent gases from other pyrometallurgical processes. This was important particularly in view of the current interest in pollution problems.Mr P. Marais thought that the authors had done themselves an injustice by not including details of the very complex processes taking place in the furnace."

Jan 1, 2014