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By A. Anderko, V. G. Papangelakis, G. Moldoveanu, G. Azimi, M. Carlos

"OLI Analyzer is a software package that uses the powerful Mixed Solvent Electrolyte (MSE) model to simulate the behavior of multicomponent electrolyte solutions from infinite dilution to the limit of fused salt, and from temperatures below the freezing point up to near critical temperature of the mixture. The software also allows the creation of thermodynamic parameters for new chemical systems unavailable yet in public-domain or commercial software databanks. This communication reviews the basics of the model and provides some examples of modeling hydrometallurgical applications with emphasis on high temperature applications, including calcium sulfate scale formation in autoclaves, high temperature pH inference and iron control. INTRODUCTIONModeling of electrolyte systems has been of particular interest to various industrial processes, such as separation processes (e.g., solution crystallization, extractive distillation, seawater desalination or bio-separations), environmental applications (e.g., gas treatment, wastewater treatment or chemical waste disposal) and hydrometallurgy (e.g., pH control and neutralization, iron control, scaling and fouling of equipment). Using a chemical model, time-effective predictions of various properties of electrolytes can be obtained, which is beneficial not only during process monitoring, but also during process optimization and process scale up. As a result, pilot scale studies can sometimes be eliminated where budgetary constraints exist. Development of such a powerful model requires the use of a speciation-based model, in which solution chemistry is explicitly addressed (as compared with some models that treat electrolytes either as undissociated or fully dissociated systems), despite being computationally challenging. In addition, as a feature of electrolyte systems, speciation equilibria inherently influence the phase equilibria due to complex formation, ion pairing, and acid-base reactions. Therefore, how the electrolyte solutions behave at various conditions may differ significantly due to the non-ideality, which must be carefully addressed to obtain a model that is applicable to a wide range of conditions such as concentration, temperature, pressure and solvent system."

Jan 1, 2012

By C. M. Brown

The semi-autogenous grinding circuit at the Utah Mines Limited, Island Copper Operation, located on Vancouver Island, British Columbia, is described. Since start-up of the operation in 1971 grinding circuit throughput has been progressively increased from the initial design rate of 30,000 to the current average 45,000 tonnes per day (t/d) of porphyry copper ore. Key developments and modifications in operating and maintenance practice that have contributed to this increase are reviewed.

Jan 1, 1985

By J. E. Armstrong

"IntroductionT'HE PRODUCTION of gravel and sand may be considered to be the major mining operation in the Lower Fraser Valley of British Columbia. At least thirty pits are in operation with a yearly production probably in excess of two million yards and a value in excess of one million five hundred thousand dollars before crushing, washing, and sizing. The value of the finished products would probably be double the above figure.Since 1949, the writer and his co-workers have been engaged in the geological investigation of the Lower Fraser valley and adjoining Coast mountains for the Geological Survey of Canada. The study, which is not yet completed, includes both bed-rock geology and geology of the unconsolidated sediments lying above bed-rock. In a rapidly expanding industrial area, .an advance knowledge of the geology may• greatly aid in future 'planning, and in many cases may .prevent not only the wastage of large sums of money, 'but possible disaster. Some of the present and future applications in which geological information in the Lower Fraser valley should be of value are as follows: the development of domestic, irrigation, industrial, and municipal groundwater supplies; drainage for industrial sites,, roadbeds, and farmlands; flood control along the Fraser river and smaller streams in the area; the location of dam sites, of major tunnels for water supply •and sewage, of road-beds, of foundation sites for large buildings .and other engineering undertakings in which geology may aid; the evaluation of oil and gas •possibilities; the production of building stone; and the production of sand and gravel, the subject with which this paper is primarily concerned."

Jan 1, 1953

By G Britton, P Moynagh

As more than a few mines gradually sink under the weight of emails, whiteboards, notice boards and ever more complex spreadsheets, the holy grail of effective short-term interval planning and control in underground mines is as far away as ever. Despite the mining industry investing ever greater amounts in planning and Enterprise Resource Planning systems, short-term plans become ever more complex and rigid. What the industry desperately needs are not more ‘disembodied voices down the speaking tubes’, but flexible and effective planning systems that encourage people to make reasonable commitments to each other so that everyone can work as a coordinated team to complete the work required each shift.One solution to the challenge has emerged. This paper describes the ‘Fewzion’ shift planning and short interval control system which has been developed at Anglo American’s Moranbah North and Glencore’s Oaky Creek coalmines in Central Queensland. Fewzion has drawn on management theory embodied in Management Operating Systems, Lean and Theory of Constraints approaches to continuous improvement to play a key role in both mines achieving record breaking tonnages.In addition to explaining the Fewzion approach, a case study is presented describing how Anglo American’s Moranbah North improved production by 39 per cent in 2014/2015 and won ‘Coalmine of the Year’ two out of the last four years and how Glencore’s Oaky Creek sustainably improved monthly development meters by 34 per cent within two months of implementing Fewzion.CITATION:Moynagh, P and Britton, G, 2017. How a frontline planning and commitment system improves trust, commitment and results in operations, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 235–240 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By D. G. Sinclair

In any discussion on the subject of mine-safety, it is well to honestly face the fact at the outset that mining is a hazardous occupation and that certain inherent dangers attach to the work, which, in spite of the greatest vigilance on the part of everyone concerned, will from time to time exact their toll of in jury or death from the underground worker. Great progress has been made of late years in narrowing down the range of these necessary risks, and, illustrative of what can be done along these lines by concerted effort, it is pleasing to read from time to time of large operating mines running for weeks, months, a year or more, without a single lost-time accident. To achieve any results in the work of accident prevention it is necessary, first, to have a definite goal, such as a no-accident period, be it a week, a month, or a year, to aim at; and, second, to set up definite standards to work by. The legal code of regulations should form the basis of all standards of work at every mine and should, for this reason, cover as far as possible all conceivable phases of operation. This represents the ideal, but in practice it is unattainable, largely because of the many variables that must be considered, due to the divergence in the scale of operations and to differing geological conditions at the different mines. Hence it becomes necessary for the operator who wishes to attain the maximum in the establishment of high standards of safe operation to so amplify the code as to meet the peculiar requirements of his operation.

Jan 1, 1930

By K. A. SPENCER

THE production of soft coal from strip mines in the United States has shown a remarkable growth in the last sixteen years, increasing from one and one-quarter million tons in 1914 to approximately twenty-two million tons in 1929. This is a growth of approximately 1660 p& cent, as compared with a growth of approximately 20 per cent in the underground mines for the same period. But even with this marked in- crease the total tonnage produced by open-face mining represents only 4 per cent of the nation's soft coal tonnage.

Jan 1, 1931

By S. A. Swensrud

NINETEEN Thirty-Six was the biggest year in volume in the history of the oil industry, and unquestionably the best since 1929 in respect to profits. The quota of new and difficult problems to face seemed a little smaller during 1936 than in most recent years, and a somewhat better balance existed between the different branches of the industry. 'Domestic consumption of gasoline in 1936, estimated at about 475 million barrels-the highest on record, was approximately 11 per cent above 1935, and 26 per cent above 1929. Demand for crude oil increased in about the same proportion: over 1935, and the average production, of about three million barrels daily,' constituted a new high level.

Jan 1, 1937

This publication summarizes the research (in-house and contract projects) programmed by the Bureau of Mines for fiscal year 1984 (October 1, 1983-September 30, 1984) under its Health and Safety Technology Program. The objective of these projects is to provide an ordered and sequenced advance toward the Bureau's overall goal of providing the systems technology required to create a more healthful and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1983

By Mehmet Guney

Acceptable working environments in production areas and service openings of Mindola Mine on the Zambian Copperbelt are currently maintained with an air volume of 1000 cu m/s and 5500 kW of installed refrigeration plant. It is planned to open up additional deeper areas of the mine for future production. Temperature problems, due to the increased heat generation from various underground sources are recognized as potential hinderances to efficient production. Findings of research work indicate that the present total heat output of 58,000 kW will inevitably increase by the second five-year period of the deepening program to 52,900 kW and by the fifth five-year period to 63,200 k\V. Estimated WB and DB temperatures, representing the total heat generation in stope faces and development headings during these same periods are predicted to increase to 53.8/40.2 °C and 35.5/42.1 °C respectively. It is assessed that the nominal refrigeration capacity needs to be progressively increased to 9,000 k\V This paper deals with the thermal problems in Mindola Mine, current heat output calculations, future prediction of temperature and heat load in various working areas of the mine with the application of computer programs and interpretation of data in order to find the effective solution for long-term planning of ventilation and air-conditioning.

Jan 1, 1982

By Florian Festge

It has been said that good things come in threes. In the case of screening for mining and quarry operations, profit comes in three distinct phases: layered, basic and sharp screening. But how good they are ? whether they maximize efficiency and improve the potential for success ? depends on having the right screen media on the deck for each of the three phases. A relatively new method for achieving that goal is a blended screen media approach that incorporates the ideal screen media for each phase and the ideal mix of media for the process overall. The goal in implementing a blended solution is to find the optimal combination of open area and durability. If this combination is found, maximum product quality and profits will be realized by increasing efficiency of classification while minimizing downtime and maintenance costs.

Jan 1, 2012

By H. Ehnes

"“Industry 4.0” – “Mining 4.0” - perhaps you have already heard of these terms? These keywords signify the next stage of industrial production. The internet and production technologies are growing closer together. Machines can communicate with one another, wherever they may happen to be located. The “Internet of Things” is the appropriate term. But what does SAFETY 7.0 mean? It is both brand new and traditional at the same time. It also has to do with the success of companies, with efficient production. And yet there is a great deal more at stake. It has to do with our lives and our safety – the supreme commodity in this world. What exactly SAFETY 7.0 means, what the number 0 stands for and the meaning of the number 7, and what this all has to do with mining will be explained in the following article. Mining is a fascinating undertaking. Mining is indispensable for a country’s economic development, whatever that may concern: infrastructure, energy supplies or raw materials for industrial production. Mining has brought forth many technological developments and innovations that can currently be found in our daily lives. Mining is impressive, grandiose and repeatedly fascinates mankind with its immense dimensions. Miners throughout the world still work hard and, for this reason, are bound to one another in a special way. In mining, every man looks out for the other; you have to be able to rely on each other. That creates a strong bond. The other side of the coin is that mining and disasters belong to normality in the media and thus also in our perception. Accidents at work and even catastrophes occur in mining, quarries, or raw material operations almost on a daily basis somewhere in the world. They are often associated with extremely serious injuries, or even a fatal outcome, for the miners affected and, in turn, dramatic consequences for the families of those involved. It could be in China, India, Russia, or somewhere in Africa, Asia or America – it mostly does not happen in front of our door or in our neighbour- hood. Perhaps because of this in the daily concert of negative headlines, we do not register these catastrophes any more in our minds. We write them off under the heading “Nothing special”, since there are, day in day out, more terrible news items about wars, civil wars, famines, or ecological disasters. Things only really change if there is a dramatic number of deaths or when we are personally affected, close by in the vicinity, or can witness the rescue action live. In Europe, these three mining disasters in particular have recently generated media resonance:"

Jan 1, 2016

Well designed and maintained haul roads are the key to minimizing truck haulage on-road hazards and costs, as well as increasing productivity. However, practically designing and managing a haul road for optimal performance is often difficult to achieve. Poorly designed and built roads exhibit high rolling resistance - a 1% increase in road rolling resistance can typically reduce speed on ramp by as much as 10% - and on the flat by up to 26%. In the current economic climate, investment and operating decisions come under scrutiny. In the long run, this scrutiny returns improved efficiencies and leaner, healthier operations. The focus of this evolving evaluation process should and will certainly fall on haulage operations ? simply by virtue of their contribution to overall cost of operations ? often in excess of 50% of total costs for deep open-pit mines. Whilst the end result - improved efficiency and reduced cost per ton hauled ? is not in itself problematic, it is the route, or process followed to achieve these savings that needs to be carefully managed. We can be guided on this journey by our understanding of how a road design is developed, and, critically, the interplay between a good design and safe, cost efficient haulage. This paper briefly summarizes the evolution of mine haul road design, from the seminal USBM work of Kaufman and Ault in 1977, through to current geometric, structural, functional and maintenance management design components. These augmented design and management guidelines have been developed over the past decade, both in response to the requirements of mine operators for more safe and efficient haulage systems, and the truck manufacturers? requirements for a more predictable and controlled operating environment. These developments have been paralleled by the need to minimize haulage hazards, both from a health and safety perspective. Whilst improved mine haul road design does indeed reduce haulage accidents, recognition also needs to be given to human factors which are a significant contributor to haulage accidents. The human factor is the most problematic to address in a road design. It is often easier break the link between the interactive effects which may lead to accidents than trying to predict and reduce human error. These human factor interactive effects include the geometric, structural and functional design components and to prevent an accident or reduce the severity of its consequences, a road should be more accommodating to human error. The more that is known about human error, the better a road can be designed to accommodate those actions or non-standard practices that would, on a poorly designed road, invariably escalate an error into an accident.

Jan 1, 2010

By A. Gontijo, A. Matos, P. Lincoln, L. Fonsecail

This paper investigates how to manage and model the vibrations caused by rock blasting in a Brazilian underground mine. Considering the frequent detonations and the previous lack of effective vibration control, understanding, and reducing the impact of these seismic waves is critical. We emphasize the use of the near field model technique, which considers the varied physical properties of different rocks, optimizes blasting plans, and minimizes damage to the rock mass. We detail a case study that demonstrates a comprehensive approach to vibration control. The discussion includes the creation of a monitoring plan, the methodology used, results and the specific challenges and solutions found during the blasting process. This study provides a practical guide for similar future projects. Finally, we present a predictive model based on the collected data, offering insights into the vibrations caused by blasting. This model helps decision-makers minimize the risk of displacing rock blocks in the blasting area, improving safety and operational efficiency

Jan 1, 2024

By Edward G. Cunney

Track in underground bituminous coal mines was investigated and technology was taken from other industries in order to obtain information on conditions that impair the safety and efficiency of the track and to develop guidelines and useful information on the construction, inspection and maintenance of mine track. Volume 1 contains information on the investigations, observed track conditions, useful technology from railroads and other industries, derivations of track condition descriptors and limits, conclusions, and recommendations. Volume 2, Guidelines, contains recommended standards and practices for mine track. It includes the relation of track conditions to safe speeds; descriptions and limits for measurable track features, such as gage; descriptions of conditions for track components that are normally not measurable, such as subbase soils; construction requirements and techniques; inspection requirements and methods; and methods for managing and performing track maintenance work. It does not repeat the summary or? derivations. Volume 3, Inspection Handbook, summarizes recommended standards and procedures from Volume II and provides related information for ready reference by inspectors in the mines. As a research product to be used in mines, it does not repeat the summary, derivations or references.

Jan 1, 1977

By Keith K. Griffiths

Computers are a valuable tool to the aggregate industry and should not be overlooked. The selection of proper mechanical components is necessary. Merely the addition of a computer to operate a mechanical system will not guarantee that the system will work. Material delivery by rail or truck for stock-piling and intra-plant material transfer can be accurately supervised by automation with simplified controls for the layman to use. There are mechanical problems that occur in material blending and load-out systems when such a system is automated. Such things as material flow, bridging, stockpiling methods, overloading of equipment and safety must be considered. How these problems can be overcome by proper selection of compatible mechanical and computer equipment will be discussed. Also, there are many individual material circuits in a plant that can be computerized at a nominal cost. This type of computer installation will not necessarily result in increased production, but it will produce greater efficiency in manpower. These small computers, binary counters, memory circuits and other devices and their application to the aggregate industry will also be presented. A careful evaluation of the mechanical and computer inter-relationship by someone understanding both "Rocks and Electronics" is essential to proper handling of material by computers. Computers for the mining industry may be either digital or analog computers. Unless the computer is to control some type of chemical process, such as a cement plant, the, analog computer is not required and the digital computer' will be quite adequate and less expensive.

Jan 1, 1967

By William Gleason

With its 2011 acquisition of rival equipment company Bucyrus International, Caterpillar added underground mining and large shovels to its line of products and further solidified its standing as the leading mining equipment manufacturer in the world with solutions for every aspect of mining. When Caterpillar spent $8.8 billion to acquire Bucyrus, the global mining business was flourishing, as mining companies around the world worked to keep up with demands for nearly every commodity. Flash forward to 2013, and the global mining landscape looks very different. Lower demand for raw material from China and India and falling commodity prices have forced most mining companies to pull back on their production. The reductions from the mining industry have hit equipment makers like Caterpillar and Komatsu hard. In October, Caterpillar reported that its quarterly earnings had fallen 44 percent. The changing conditions have also changed the narrative from Caterpillar and other equipment makers to customers from offering solutions to move the most tons per hour, to now offering solutions for the lowest cost per ton. In September, Caterpillar hosted some of its mining customers and the trade press at its Tinaja Hills Demonstration and Learning Center near Tucson, AZ to talk about its range of products, from its MineStar System designed to help increase efficiency through better equipment management and planning, all the way up to the massive Cat 7495 and 7495HF electric rope shovel lines acquired through the Bucyrus takeover

Dec 1, 2013

By H. Simpson

Middelburg mine is an opencast export mine operating in the Eastern Transvaal Coalfields of the Republic of South Africa (Figure 1). The mine was commissioned in 1983, to its original design capacity of 4.25 million sales tonnes which was subsequently raised to 5.5 million sales tonnes in 1989. This increase in export tonnage was brought about through an increase in the mines export allocation and the revision of management strategies. The maintenance of this increased tonnage with minimal additional capital has been achieved through improved operational efficiencies and the upgrading of planning operations through the purchase of an Enhanced Mine Scheduling Software Package (EMSSP/MINESTAR). Simultaneously with this requirement were additional factors that contributed to the implementation of the EMSSP. The mine was owned by a joint venture of two partners and is operated by Middelburg Mine services (Rand Mines Pty. Ltd) (Figure 2). This structure of ownership required the evaluation of numerous planning options to be under-taken concurrently and hence the need for an efficient streamlined scheduling pack-age that could fulfill this requirement. Compounding the EMSSP needs further, were the problems experienced in the export market, these being the external pressure from current and new suppliers in the market place which obliged management to provide solutions to rapidly changing market conditions. These fluctuating market conditions have had a direct effect upon the mine's planning strategies because of the large percentage of the mine?s sales sold on the international spot market. The sanction factor for all South African exporters has had a negative effect upon price and this was compounded further through internal competition in 1987 via suppliers attempting to maintain the market position.

Jan 1, 1991

By AIME AIME

THE annual fall meeting of the Institute of Metals and the Iron and Steel divisions, in conjunction with the American .Society for Steel Treating and the Metal Congress and Show, at Boston was from many standpoints the most successful we have had to date. While many faces were missing from the various gatherings, the Institute registration reached the high mark of 324 members and guests. Cooperating with the Steel Treaters were also the American Society of Mechanical Engineers, the Society of Automotive Engineers and the American Welding Society. ,The meeting was, as usual, a three-ring circus with technical sessions 'galore, plant .trips, visits to the Exposition, social events such as lunch- eons and dinners as well as entertainment for the ladies present.

Jan 1, 1931

By Floyd G. Anderson

The increasing trend toward use of continuous-type mining machines created a significant dust problem in coal mining, which resolved itself into three categories: Visibility at face, deposition on return airways, and the potential health hazard. The control measures applicable to these conditions and studied or developed from 1955 through 1957 are summarized and reviewed in this report. Other important problems brought into focus during the same period were radiation exposure in uranium mining and high temperature and humidity. Although temperature and atmospheric pressure alone may not be contributing factors in the incidence of silicosis, the few mining companies who operate under the extremes of these conditions are dust conscious and keep dust-control engineers on their operating staffs.

Jan 1, 1961

By J. F. McIlwain

As part of its goal to minimize the requirements for critical materials, the Federal Bureau of Mines has investigated the consolidation of an iron-base superalloy (20 pct Cr, 5 pct each Ni and Mn, 1 pct each C, W, Mo, and Cb, and the balance Fe) and its modifications by powder metallurgy (P/M) techniques. Vacuum-atomized, prealloyed powder was used. Consolidation was by sintering of cold-pressed alloy powder, or by forging plus rolling or extrusion of canned powder. Several commercial lubricants were evaluated in the pressing operation. At 50-tsi compacting pressure with up to 3 wt-pct lubricant, green strengths did not exceed 1,000 psi. Powder sintered just below the solidus temperature attained a tensile strength of 69,000 psi and 4 pct elongation. Liquid-phase sintering produced higher densities, lower tensile strengths, and nil ductility. Canned powder was forged and rolled at 1,200° C, yielding a 100-hr rup¬ture strength of 9,800 psi at 815° C and a room-temperature tensile strength of >130,000 psi at 6 pct elongation. Heat treatment of modified P/M iron-base alloy containing 0.63 pct C resulted in a 100-hr rupture strength of 17,000 psi. Oxidation resistance at 805° to 815° C of the forged and rolled P/M iron-base alloy was similar to that of the cast iron-base alloy and supe¬rior to conventional stainless steels.

Jan 1, 1981