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By John D. Price

In the constant search for ways and means of improving the quality of coke and thus making its use at the blast-fornace more satisfactory and economical, it has become increasingly evident that the present laboratory tests do not show the full picture of a coke's value as a blast-furnace fuel. This fact was recognized by Dr. A. C. Pieldner thirty-five years ago: (Ref. 1) here is perhaps no phase of fuel technicology which has aroused more discussion or regarding which there is more difference of opinion than the properties of coke which make it most suitable for blast-furnaces and other uses." Dr. Fieldner followed this assertion with a statement to the effect that men who write on this subject today (1923) have, because of conflicting experimental evidence brought forth in recent years, far less positive opinions on the matter than did writers of some years past. One is led to wonder if these statements are not just as true now as they were when first made.

Jan 1, 1959

By Mariano de Córdova

In this paper, the coke oven life prolongation technology is reviewed from different points of view: blend design; battery heating; operational control; refractory maintenance. A summary of major inspections in critical areas, for the evaluation of the battery conservation situation is presented. A discussion on tools for the diagnostics of the degree of damage is carried out.

Aug 16, 2017

By R. A. Beall

This bulletin reviews the historical background of the cold-mold arc-melting technology, with specific references to the development that led to homogeneous zirconium ingots. Descriptions are given of modern production arc-furnaces for vacuum melting of troth exotic and conventional metals. Besides zirconium, specific data are given for production of chromium, thorium, and copper. The development of the skull-casting technique for titanium is detailed, and the application of the technique to such refractory metals as molybdenum and tungsten is described. Factors of operation of the apparatus and furnace design are considered.

Jan 1, 1968

By F. Alsobrook

Coleman Quartz Inc. has a long history as the sole U.S. producer of lascas for the cultured quartz growing industry based on its unique deposits in Arkansas. Since 1989 the company has also been producing metallurgical grade silica for the ferrosilicon industry from a deposit of unusually pure Arkansas novaculite. This paper chronicles Coleman's trans-formation of an abandoned railroad ballast quarry into a generator of $1.5 million in annual sales to a nontraditional novaculite market. Potential additional applications for this high quality silica rock will also be mentioned.

Jan 1, 1992

By D Kilkenny, D Nardini, P Kline

This paper is a case study highlighting learnings and success in two areas challenging underground miners: change management and collaboration. It examines the implementation process of a new automated loading system in the bulk stoping area of Telfer Mine in Western Australia, controlling multiple load haul dump machines. Here, the new technology has brought together different functions and different companies to deliver a well performing automation system in a changing and challenging mining environment. The introduction of a new and different technology on site has driven collaboration between all stakeholders to break down the traditional barriers to achieve the sustained performance required. Historically, different teams have operated within silos and not always aligned to deliver a ‘best for project’ solution. Technical teams focus on the mine design, maintenance teams focus on reliability and operations execute the plan. Mining contractors focus on productivity and cost. Manufacturers focus on supply of goods and service. Optimising each silo individually is not guaranteed to provide an optimal mining solution. Involving elements from each team as seen at Telfer, has resulted in an optimal mining solution for the automated loading system. A change of focus from the technical teams to include automation parameters in the mine design; operability and maintainability built into the system design allowing for collective ownership and responsibility resulting in a more resilient solution. The implementation of the new technology was not only a technical change but more importantly, successful management of change. Elements of successful change management such as communication, vision, leadership and planning, are essential to harness a trusting site culture which is responsive to new technology. Learnings and challenges from this change process will also be discussed with the intent to improve the success rate and timelines of technology implementations in the future.

Mar 15, 2021

By Tony Breuer

Can international development NGOs and the mining industry find common ground and work together in the Third World? The Canadian Hunger Foundation/PARTNERS in Rural Development (CHF-PARTNERS) has, over the past forty years, implemented more than 800 rural community development projects in some 38 countries of Africa, Asia, and the Americas. Working with or for the Canadian mining industry offers both opportunities and risks. We can help a mining company ensure that the workers, their families and communities share adequately in the economic and social rewards from a mining operation in their area. We can contribute to the provision of sustainable livelihoods when an operation winds down. The company?s reputation as a good corporate citizen can be enhanced. On the other hand, mining companies and NGOs have generally very different values and missions. The risk of misunderstandings from conflicting motives and work practices is correspondingly high. Both partners must state their values and expectations clearly at the start of collaboration. The NGO must ensure that the company abides by acceptable ethical standards. It must not directly or indirectly subsidize a private company from its charitable donations. The mining company must satisfy itself that the NGO has the capacity, resources and experience to produce the results expected.

May 1, 2001

By Robert Bachus, Jamey Rosen, Fabio Santillan, Georgette Hlepas

"A seepage barrier of length 4,800 feet and maximum depth 144 feet is being installed at Bolivar Dam in Ohio. This project is owned by the United States Army Corps of Engineers and contracted to Treviicos South. Many data types are being collected, synthesized and analyzed on a nearly real-time basis to monitor and track dam construction using several technologies including an enterprise relational database and web-based Geographical Information Systems. These data are being collected by both the owner and contractor and managed by the data subcontractor, Geosyntec Consultants. Each of the owner and contractor brings their own list of goals and desires to the data management program, and the subcontractor’s duty is to address these goals with minimal compromise by either party. The owner requires comprehensive, transparent and timely access to data in both “executive summary” and detailed formats. The contractor requires immediate analysis of disparate data to determine (for example) if a given excavation meets the specified tolerance and continuity requirements. This paper will describe the tools and methods used to store, analyze and visualize these data and discuss how each party’s needs were met in a collaborative system.INTRODUCTIONThe 4,800 foot long seepage barrier under construction at Bolivar Dam requires the collection, organization, and sharing of several types of data. These data include drawings and borehole logs that existed prior to construction; data collected during construction (seepage barrier panel composition and verticality data, slurry quality control and quality assurance data, grouting records, etc.); and instrumentation data collected and reviewed throughout and beyond construction. Each of these data streams require input and review from the Owner (United States Army Corps of Engineers (USACE), responsible for quality assurance and the ultimate consumer of the data), the Contractor (Treviicos South, responsible for the construction of the seepage barrier, its quality control and analysis of the data per the Contract Specifications), and the Data Management Subcontractor (Geosyntec Consultants, responsible for organizing and presenting the data to meet the needs of the Owner and Contractor). While all parties work with the same common goal, i.e.: producing a high quality product in an efficient manner making dam safety paramount during construction, and require immediate and comprehensive access to these data, the needs and desires of the parties differ. The challenge presented to the Data Management Subcontractor is to synthesize these data into a series of tools and reports that meet each of these needs."

Jan 1, 2017

By S. K. Chaudhuri

With a growing emphasis on maximizing the value by rapidly deploying it across their assets, mining firms are eager to identify any issues that may hinder such efforts and to refine their approaches to overcome them. As such a CDE vision can be considered realized when the following components are addressed and functioning as intended - People: the right resources working together and efficiently to achieve shared goals, Process: well-defined workflows mapped out for key value processes, Technology: availability of the correct tools and applications to increase efficiency in work execution and Locations: regional locations/ sites that need to be linked for collaboration and information exchange. For the above vision, an approach that considers the degree of interaction between the roles in metallurgy operations, mineral resource planning, mine engineering, plant operations, logistics and infrastructure, and which accounts for the current technology states across these groups to determine sub-processes where the impact of a CDE will be the most is critical. In effect, CDE is more about transforming an organization?s operational philosophy than a technology driven project. This paper examines the definition and components of a CDE in a mining context. Real-time operations co-ordination, maintenance interventions, production analysis and optimization processes are examined along with current state technologies and manual processes as candidates which are likely to result in most benefits from collaborative work processes. Finally, the paper examines technologies that can be used to further enable a collaborative working environment.

Sep 1, 2012

By H Guthrie, J Hodder, J Bain, S Durkin

Australian mines have traditionally relied on diesel powered vehicles to fulfil their light vehicle needs. There are many reasons for the resources industry to review its use of diesel-powered vehicles. The international industry has developed projects to explore the use of Battery Electric Vehicles (BEV) as a more sustainable alternative to traditional diesel-powered vehicles. While the technology for cost-effectively applying modern high-performance lithium-based batteries to the mining environment has existed for over a decade it is yet to be widespread throughout the industry. Through the collaboration of Safescape, 3ME Technology and Kirkland Lake Gold, with funding from Mining Equipment technology services (METS) Ignited, the project has focussed on advancing the Australian METS sector’s capability in the rapidly approaching implementation of BEV technology. This paper reports on the collaborative approach to develop a prototype vehicle; explains the selection criteria for the various components of the vehicle; and details the risk-based approach to developing a scalable product to replace existing underground light vehicle fleets. The prototype vehicle was tested underground at Kirkland Lake Gold’s Fosterville operations in Victoria beginning in October 2019. Reporting from these trials focusses on the key factors affecting underground operations. These include driveability, safety, charging and cycle times. Gathering data around energy consumption through normal daily duties enabled a model of energy consumption and charging requirements to be developed such that various applications of the electric vehicle can be considered against existing diesel-powered vehicles. This has provided insight into the impact on daily operations, and the way forward for large scale implementation.

Mar 15, 2021

A knowledge of the mechanics of wave propagation through the earth is essential if reliable communication systems are to be designed for coal mine environments. To obtain a reliable basis from which accurate propagation predictions could be drawn, a series of theoretical studies have been prepared for the US Bureau of Mines by Mr. Ramsay Decker of Spectra Associates, Inc. through a subcontract with Collins Radio Group. These reports formulate the analytical techniques from which we may derive frequencies and antenna configurations that yield the optimum signal-to-noise ratios over the greatest distances in mine environments. The reports of sections 2 and 4 deal with analytical techniques for determining the signal-to- noise ratio within a mine environment for loop-to-loop and line source-to-loop antenna con- figurations. The analytical results of these reports were then implemented into computer programs to obtain predictions concerning through-the-earth signal propagation. These preliminary predictions are based on noise data compiled by Bensema, Maxwell and Stone, and WVU prior to the extensive research conducted by the National Bureau of Standards (NBS). These initial measurements indicated a 20- to 30-dB lower noise level than that measured recently by NBS. The recent NBS data is that used by Collins in the final predictions. The following outline indicates the order and subject matter treated in the subsequent sections: Section 2 - Signal-to-Noise Analysis for Loop-to-Loop Mine Communications Section 3 - The Horizontal Electric Dipole Section 4 - Signal-to-Noise Analysis for Down-Link Line Source Mine Communications Section 5 - LF Communication Section 6 - The Application of Recent NBS Noise Data to Mine Communications Section 7 - Analysis of Mine Communication Propagation Programs

Nov 15, 1974

By Andrew Meyer

As a producer of gold and platinum, Colombia is most emphatically an important country. Last year it produced 656,000 oz. of gold-twice as much as any other country in South America, in fact accounting for a third of the production of that continent. In platinum, world data for 1941 are not available, but in 1939 Colombia exported 39,000 oz., apparently ranking fourth among the world's producing countries, being exceeded only by Canada, Russia, and the Union of South Africa. Colombia was always a mining country. Centuries before the Conquest, Indians mined gold, copper, silver, salt, and emeralds. The Spaniards simply intensified mining. The Bank of the Republic states that from 1493 to 1940 52,177,427 oz. of gold was produced by Colombia, and official Chocó statistics show that about $60,000,000 worth of platinum was mined between 1908 and 1941. These figures are impressive indeed considering that only rich pockets and surface showings were mined by the ancients.

Jan 1, 1942

By B. E. Fernow

MINING interests in the Western mountains are very seriously affected by the danger to property and life from destructive snowslides and avalanches. This is a danger which the miner has largely brought upon himself by an improvident stripping of the timber from the mountain slopes, and, therefore, he might be expected to take an interest in the reforestation of the areas thus devastated. A canvass was lately undertaken by the writer to ascertain approximately the extent of the damage suffered from this source, but the difficulty of obtaining reliable data has proved too great to permit, as yet, even an approximation. So much, however, is certain : that the loss of life is considerable, and that much property is destroyed almost every winter. True, neither the number of avalanches, nor their destructiveness, nor the amount of loss compares with what Switzerland experiences. This is due not only to the greater precipitousness of the Alps and to different climatic conditions, but also to the fact that in Switzerland a larger number of settlements is exposed to these dangers. A very complete and interesting official report on the very numerous and destructive avalanches occurring in Switzerland during the season of 1887-1888 has just been published as a contribution to the inquiry, whether and how these dangers can be averted. Peculiar weather-conditions, in addition to heavy falls of snow, were the reasons for the frequency of the phenomenon during that winter. This report records 1094 avalauches, by which 850 houses were destroyed or severely damaged; 84 persons and 752 cattle were buried; traffic on railroads and on highways was greatly interrupted, and the damage to personal property alone was valued at over $100,000. One of these snow-masses covered about half an acre, with a cone 250 feet in height. During the same year in Tyrol the number of avalanches was 3647. Of these 1355 run over permanent beds; that is, they recur annually, so that they are

Jan 1, 1890

By A. N. Rogers

Jan 1, 1883

By Arthur W. Gray

The thermal analysis of a metal or an alloy is ordinarily made with the aid of heating and cooling curves in which transitions are indicated by the rapid changes in curvature that accompany changes in the rate of heat absorption or evolution. Analysis by the method that depends on the change in thermal expansivity is not customary, partly, at least, because of the difficulties involved in making the necessary measurements. However, under certain circumstances, the dilatometric method of analysis may possess advantages over the thermometric method that will justify the additional trouble required. The addition of 1 per cent. of zinc to an alloy has been found to produce upon the volume changes that take place during transition effects that suggest the possibility of using the dilatometric method of thermal analysis as a rather sensitive means of obtaining chemical information. Although the illustrations presented in this paper are drawn from data obtained during an investigation of dental amalgams, similar phenomena can doubtless be observed with other alloys. Some of the results found during an investigation made in 1917l have been confirmed by data on the thermal expansivity of amalgams published by Souder and Peters of the Bureau of Standards in reporting tests of dental materials.2 Although the Bureau of Standards made experiments for the purpose of discovering effects of including zinc as one of the constituents of a dental alloy—a matter much discussed in dental literature but without the presentation of reliable experimental evidencae to support the views of either side—the reports of the tests made by the Bureau give the impression that certain striking phenomena associated with the presence of zinc were not noticed. Among such phenomena arc those connceted with the conditions that determine whether or riot a specimen of amalgam becomes covered with droplets from which crystals develop.

Jan 1, 1921

"This research aims at improving the beneficiation of coals and minerals in fine and ultrafine size fractions. A widely used method for upgrading fine and ultrafine particles is froth flotation, which is generally classified into mechanical flotation and column flotation. The present work is focussed on column flotation. A flotation column equipped with a conventional bubble diffuser/sparger was used with oscillatory air supply generated using a fast-switching solenoid valve. The flotation tests were carried out for coal particles and mineral particles, respectively, and a comparison in flotation performance was made between oscillatory air supply and steady air supply. It was found that use of oscillatory air supply with a proper valve switching frequency and on/off time ratio to replace steady air supply could lead to increased recovery of coals or minerals by more than 14 percentage points and substantial reagent cost savings. The improved flotation performance was attributed to enhanced gas dispersion and flow conditions. This research offers a simple new approach to improving the beneficiation of fine coals and minerals with using flotation columns.INTRODUCTIONFroth flotation has been widely used for the separation and concentration of fine coals and minerals by exploiting the difference in their affinity to air bubbles in aqueous medium. Froth flotation is an effective method for beneficiation of coal and mineral particles in a certain size range. It remains difficult to upgrade ultrafine mineral particles. One of the reasons for the ineffective flotation of fine particles is the low probability of bubble-particle collision in the collection zone (i.e., the pulp zone). According to Reay and Ratcliff (1973) and Yoon and Luttrell (1989), the probability of collision is significantly affected by bubble size and particle size, and the collection zone recovery can be increased by decreasing the bubble size."

Jan 1, 2018

By R. Duinker

"This paper, an update to the 2003 paper titled "Knowledge, Technology and Profit" (Twigge-Molecey, 2003) analyzes 45 "problem projects" from the mining and metals industry over the last eleven years representing $133 billion in CAPEX. The projects have been designated as "problem projects" as they did not meet their owner’s initial expectations for project performance as defined in the paper. This paper explores some of the challenges that were present, through interviews with the knowledgeable individuals that were familiar with the projects and investigations using publically available information. The aim of the exercise was to identify the key challenges faced by the projects, and the contributing factors that led to the project failures so that the lessons can be applied to future projects.The project challenges have been categorized into four themes, technical, organizational, environmental & social and missing "homework" prior to board approval. Of noteworthy interest is that environmental permitting aspects have risen to become a significant and notable contributor to problem projects in 11 years from 2003 to 2014. It is further observed that many projects have been challenged by increasing size and complexity and with execution in more remote locations since the previous paper.It is a reality that every project will face challenges. Some projects are simply more challenging than others, and success or failure of the project is often determined by whether the project team is fully prepared to respond to the challenges. This in turn is largely dependent on whether the project "homework" was adequately completed and considered for all aspects of the project."

Jan 1, 2015

By Jean-Pierre Côté, Alexandre Noiseux

"Hatch and ArcelorMittal Mines Canada have combined their expertise to develop a dynamic model of the latter’s Iron Ore Pellet Plant in Quebec, Canada. This model was used to predict the benefits of different expansion projects, as well as asses the best implementation sequence.Two modelling tools were used: a discrete-event simulation software used to develop the dynamic model of the Pellet Plant and an in-house process simulator. The latter was based on operational data and known behavior of the process, and was calibrated with historical data gathered under different operating conditions.The results of the process simulator were used as input values for the dynamic model, which included all of the operation steps of the pelletizing process, from concentrate beneficiation to baking of the pellets. The model has been validated by assessing its capacity to represent adequately the operation of the plant during a 20-month operating period. It was able to reproduce the plant capacity within a precision of 1.2%.Simulated “what-if” scenarios allowed quantifying the production increase associated with the addition of new equipment such as ball mills or balling discs, implemented individually or in combination. Results revealed a potential 10% increase in the annual plant production by adding additional equipment in the two most limiting sectors of the plant, grinding and agglomeration. The simulation results made it possible to quantify the synergistic effect of two projects on plant throughput; the model showed that the combination of two projects resulted in a greater production increase than the sum of the same projects evaluated individually.Now that it has proven reliable, the simulation tool can readily be used by ArcelorMittal Mines Canada process engineers to perform simulations for equipment optimization, and to evaluate the impact of various operating parameters such as equipment availability and tonnage, product mix or concentrate quality. This work showed that a reliable model can be developed based on known parameters in combination with the proper integration of the process knowledge."

Jan 1, 2010

By Wright JK, Turner RE, Batterham RJ, Morrison AL

Simulation can play an important role in the design, optimization and control of complete industrial processes, the most appropriate method depending on the particular application. Most commonly, process models or simulators are means of representing the process which are either purely mathematical or physical. Mathematical models, however, almost invariably need to be based to some extent on experimental data or require experimental verification before they can be used with confidence. Ways in which experimental and mathematical modelling techniques can be combined to best effect are discussed, with reference to the simulation of iron ore induration and direct reduction processes. A novel method is presented for the simulation of direct reduction shaft furnaces. Small scale apparatus has been developed in which ore or pellet samples are subjected to the changing environment of the industrial process. The time dependent conditions (solid temperature and gas compositions) are provided by a mathematical representation of heat transfer and the conservation of mass and energy in the process Simulated.

Jan 1, 1986

By Walter Knox, Charles H. Sawyer

All of the coals commonly used in domestic bituminous stokers form coke, and satisfactory operation depends upon the fact that the coke formed is so weakly bound together that it breaks readily in the normal operation of the stoker and automatically maintains a good fuel bed. Some coals, because of their tendency to form solid, blocky coke, are practically excluded from use in small domestic stokers as now built. Other coals, some among the best stoker coals available, can form this troublesome coke under certain conditions. Many contradictory methods have been offered as cures for coke formation. Generally the procedure has been to try various adjustments until a combination was found that seemed to give better results. Such random methods of treatment have not provided any reliable information as to causes. The present paper covers a comprehensive test program undertaken by the Koppers Company's Stoker Coal Research Laboratory at Kearny, N. J. The program had two main objectives; first, to discover what factors affected coke formation, and second; to define corrective steps that could be applied in stoker service work. Conclusions and Results i. The design of the stoker outweighs in importance all other factors capable of improving coke formation. 2. Insufficient air supply aggravates the formation of large blocky coke, although raising the air above 30 to 40 per cent excess (as determined during steady running) does not further improve the character of the coke formed and only reduces its accumulation at the expense of efficiency, increased fly ash, poorer clinker-ing, and other disadvantages. 3. Increasing the coal feed results in a somewhat more friable coke structure and is recommended for persistently troublesome jobs. 4. Increasing over-fire draft improves the character of the coke formed and reduces troublesome accumulations by accelerating off-period burning, although at some expense in efficiency and some increase in fly-ash accumulation. 5. Coke structure was not substantially improved by blocking some of 'the retort tuyeres, although the blocking of tuyeres at the feed-screw end of a rectangular retort did lead to somewhat improved performance, possibly because of considerably better distribution of coke in the fuel bed. 6. With the equipment tested no difference was shown between installation of the same stoker in a steam boiler and a warm-air furnace, or between a sand-filled and a ventilated type of hearth. 7. The following design features had no noticeable effect on coke formation: a. Presence or absence of coal-tube air as provided by many manufacturers to eliminate smoke-back. B. Presence or absence of a flap damper ill the air duct to minimize off-period burning. c. Continuous or intermittent (ratchet and pawl driven) movement of fuel feed screw.

Jan 1, 1944

By Charles H. Sawyer, Walter Knox

All of the coals commonly used in domestic bituminous stokers form coke, and satisfactory operation depends upon the fact that the coke formed is so weakly bound together that it breaks readily in the normal operation of the stoker and automatically maintains a good fuel bed. Some coals, because of their tendency to form solid, blocky coke, are practically excluded from use in small domestic stokers as now built. Other coals, some among the best stoker coals available, can form this troublesome coke under certain conditions. Many contradictory methods have been offered as cures for coke formation. Generally the procedure has been to try various adjustments until a combination was found that seemed to give better results. Such random methods of treatment have not provided any reliable information as to causes. The present paper covers a comprehensive test program undertaken by the Koppers Company's Stoker Coal Research Laboratory at Kearny, N. J. The program had two main objectives; first, to discover what factors affected coke formation, and second; to define corrective steps that could be applied in stoker service work. Conclusions and Results i. The design of the stoker outweighs in importance all other factors capable of improving coke formation. 2. Insufficient air supply aggravates the formation of large blocky coke, although raising the air above 30 to 40 per cent excess (as determined during steady running) does not further improve the character of the coke formed and only reduces its accumulation at the expense of efficiency, increased fly ash, poorer clinker-ing, and other disadvantages. 3. Increasing the coal feed results in a somewhat more friable coke structure and is recommended for persistently troublesome jobs. 4. Increasing over-fire draft improves the character of the coke formed and reduces troublesome accumulations by accelerating off-period burning, although at some expense in efficiency and some increase in fly-ash accumulation. 5. Coke structure was not substantially improved by blocking some of 'the retort tuyeres, although the blocking of tuyeres at the feed-screw end of a rectangular retort did lead to somewhat improved performance, possibly because of considerably better distribution of coke in the fuel bed. 6. With the equipment tested no difference was shown between installation of the same stoker in a steam boiler and a warm-air furnace, or between a sand-filled and a ventilated type of hearth. 7. The following design features had no noticeable effect on coke formation: a. Presence or absence of coal-tube air as provided by many manufacturers to eliminate smoke-back. B. Presence or absence of a flap damper ill the air duct to minimize off-period burning. c. Continuous or intermittent (ratchet and pawl driven) movement of fuel feed screw.

Jan 1, 1944