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By Mohammed Ali Shah, Martin Waller

The mining industry depends to a large extent on the availability of high performance equipment. For drilling this means a requirement for well engineered, reliable machines with mechanised handling and widespread utilisation of automatic control. Such machines enable performance optimisation of drilling operations and integration into a high productivity mining system. A review is presented of the current status of drilling technology as applied to the mining and minerals industry. This covers developments in: drill bit materials and design; drilling techniques; machine design; mechanisation; automation; and drilling control. It also covers the ways in which current and future mining methods and practices will influence the applications and demands placed on drilling activities. The probable impact of current research on the industry is discussed.

Jan 12, 1992

By G. W. Jones

An important activity of the Bureau of Mines is the promotion of safety in mining and industry. As a part of this program, the Bureau determines the explosion hazards of combustible gases, vapors, and solids and investigates means of controlling and preventing explosions. The limits of inflammability (explosive limits) of combustibles are not only of theoretical but also of practical importance, because many industries at one time or another contend with explosive mixtures of combustible gases or vapors in their manufacturing processes. At present many new organic compounds are being manufactured, transported, and used in huge quantities which a few years a ago were only laboratory curiosities.

Jan 1, 1941

By K. Chomyn, R. Veenstra, P. Zangeneh, Hatch Ltd., C. Van der Woude, H. Ghorbani

"The furnace is the heart of smelting operations, and therefore the performance, reliability, and campaign life of the furnace are critical considerations. Furnace refractory is exposed to high temperatures and other harsh operating conditions causing brick erosion, crushing, and cracking, typically limiting the furnace campaign life and requiring costly furnace shut-downs for refractory re-lining. Despite extensive study, the in-service thermal / mechanical stresses in these complex refractory systems are not generally well understood. Hatch has developed a thermal-mechanical finite element analysis (FEA) based furnace refractory modeling approach that allows for the quantification of refractory movements, load distribution, and thermal / mechanical stresses.Due to the complexity of the refractory system, a range of models are used to identify and assess damage mechanisms and design improvements, including: 2D models, to capture expansion and movement of individual bricks, changes to load paths, and thermal stresses; and 3D models, to include the effect of differential expansion between bricks in each course, and assess overall load distributions. The 2D and 3D analyses include the effect of nonlinear temperature-dependent properties, thermal expansion, movement of individual bricks with frictional contacts (i.e., gaps can open, bricks can slide), and brick tensile or compressive failure. Both as-built and damaged conditions can be investigated (e.g., after bath zone brick erosion), for circular and rectangular furnaces. 3D models also include papering and brick joint & interface action.Analyses using these models have shown the importance of thermal stresses, papering, and geometry / arrangement of individual bricks. Results have been used to identify and assess damage mechanisms, showing good alignment with furnace autopsy observations. By using this FEA-based approach to quantify the refractory design, the risk of damage can be significantly reduced, low-cost design changes can be identified, and the furnace campaign life can be extended.INTRODUCTIONThe furnace is the heart of smelting operations and therefore the performance, reliability, and campaign life of the furnace are critical to the success of the smelting operation. Furnaces are inherently exposed to high temperatures, often in excess of 1600°C (Holappa, 2004), and furnace operating power has progressively increased over time (Voermann, Gerritsen, Candy, Stober, & Matyas, 2004). The refractory system must withstand high temperature, high heat flux, and other harsh operating conditions. These conditions are particularly significant for the furnace hearth, and can lead to damage including brick erosion due to molten material flows, crushing due to thermal expansion loads, and cracking due to severe thermal gradients within the bricks. Refractory damage typically limits the furnace campaign life, requiring costly furnace shut-downs for refractory re-lining (repair or replacement). In some cases the refractory may lose integrity causing damage to nearby equipment and harm to personnel."

Jan 1, 2016

By G. Önal

Recovery of nickel and chromite from the tailings has been studied on the samples with 0.214 % Ni and 5.10 % Cr2O3 content and taken from Orhaneli Chromite Concentration Plant. Mineralogical examinations of the samples showed the existence of chromite, olivine, pyroxene, chrysotile, anti-gorite, chlorite, idingite, tremolite and calcite together with trace amounts of millerite, pentlandite, pyrite, pyrrhotite, hematite and limonite type iron oxide minerals in partially serpantinized dunite type particles. In order to recover chromite from Chromite Concentration Plant tailings Mozley Table and Knelson Separator are used and concentrates containing approximately 42% and 46% Cr2O3 are produced respectively with 40% recovery. Most of the nickel remained in the tailings. Therefore, acidic leaching tests are performed in order to dissolve nickel from these tailings. Effects of particle size, acid concentration, temperature, leaching time and solid/liquid ratio on the nickel leaching efficiency are investigated. The optimum leaching conditions are found as 250 g/L acid concentration, 1/5 solid/liquid ratio, 2 hours of leaching time and 60°C temperature, almost all nickel is dissolved at the optimum conditions and acid consumption is about 841 kg/t. Repeated leaching tests are carried out in order to have enough Ni content in the leach liquor for the further treatment of solutions. After repeated leaching tests, leach liquor contains 3 kg/m3 Ni, 48 kg/m3 Fe, 2.2 kg/m3 Si, 23 g/m3 Cr and 590 kg/m3 H2SO4. Ni is recovered from that solution by precipitating with H2S followed by HNO3 dissolution and precipitating Ni as hydroxide with 63% Ni content. Leach cakes are subjected to the gravity separation (Mozley table) to recover the remained chromite and a chromite concentrate with 47% Cr2O 3 content is produced with 53% recovery. As a result of the abovementioned tests, a conceptual process flow sheet is proposed for the treatment of these chromite concentration plant tailings.

Jan 1, 2014

By A. M. Esteves

This paper offers an overview of local content policies and practice in the mining sector. Specifically, the paper aims to answer the question of how national and regional governments, industry and civil society can work together to seek an optimal outcome while pursuing their diverse objectives. The paper begins by defining local content and its scope at the subnational level. Specific recommendations for the design of local content policies to mitigate social, economic and governance risks are developed. The document then offers some recommendations regarding the role of partners in design, implementation, monitoring, and enforcement of local content policies.

Aug 1, 2013

By Peter C. Jones

Owing to the inadequacy of the ore transport system at Cassiar in the late 1960's, a new facility was required. This paper traces the various alternatives considered and gives a description of the tram line as installed. The problems encountered, changes made and future modifications are discussed in detail, together with the effects these have on maintenance and operations.

Jan 1, 1978

By Earle E. Schumacher, Alexander G. Souden

IN the field of physical metallurgy it is becoming increasingly difficult to keep abreast of the recent develop¬ments since the diversity of investigations is so great and the literature so voluminous. The purpose of this review is to present the more important advances in the nonferrous field during the past few years, the topics discussed being classified broadly as fundamental and practical. The former includes those studies that have done most toward developing the basic science of metals and alloys, and the latter includes technical developments and applications. With the rapid growth of the metal

Jan 1, 1938

By P. Tracy

An advanced real-time monitoring system, called a "Tapblock Diagnostic System" is under development to help furnace operators manage the operation and maintenance of their tapblocks. The life of a water-cooled tap block in a smelting furnace ranges from several months to several years, depending on the operating conditions. Tapblocks are typically replaced at regular maintenance intervals; a strategy based largely on historical records and not on the actual condition of a particular tapblock. The Tapblock Diagnostic System monitors the tapblock throughout its life and accumulates probable wear events to help the operator assess the residual integrity of the tapblock. Benefits of this system include the ability to provide early warnings of tap block wear to provide improved safety and maintenance planning. Using cooling-water flow together with copper and water temperature measurements, the system performs calculations that compare the present tapblock performance with the expected operating envelope using a multivariate statistical method (Principle Component Analysis). The operating envelope is pre-calculated for a wide range of operating conditions using transient thermal modeling (Computational Fluid Dynamics). A state indicator in the form of a green, yellow and red light is used to inform operators of the tapblock performance and health status.

Jan 1, 2007

By Armando Vazquez

Steel Dynamics Inc. (SDI) and Tenova Goodfellow Inc. (TGI) have successfully commissioned the first hybrid extractive/laser system for continuous and full spectrum analysis (CO, CO2, O2, H2 and H2O vapor) on two twin shell furnaces at Butler, Indiana. NextGen® technology using off-gas analysis as a main tool for EAF practice optimization is a proven effective method for improving plant productivity. Significant benefits attributed to the NextGen® system are operational cost reductions through the use of real-time dynamic control of chemical energy and improved environmental conditions through reduced GHG emissions. Additionally, the implementation of Tenova’s Water Leak Detection Technology® has shown results as an effective tool for operators to identify in real-time the presence of water during both reducing and oxidizing conditions. This paper will include project details, trials and results and will also outline the latest hardware developments and multipoint capabilities

Oct 30, 2017

By M. Opler

Presently, only a few large copper refineries are able to produce Grade A cathodes from copper scrap. Today's technology needs large plants for smelting, converting or refining the main impurities and casting the anodes for electrolytic refining. A new ECUPREX® PROCESS, by-passes all pyrometallurgical operations and produces directly copper cathodes starting from copper scrap with high lead and tin contamination. Copper scrap from chopped cables, copper cements and electronic scrap are suitable feed for ECUPREX® PROCESS. This process uses a non-conventional electrolyte and produces a surprisingly high quality, smooth cathode assaying only few ppms of total metallic impurities. Bench-scale work followed by a successful mini-pilot plant run, has led to the construction of an operating pilot plant equipped with a 1,000 Ampere cell. The results of the operations of this pilot plant are presented and described in this paper.

Jan 1, 1995

By E. W. Lucht

THE term "high pressure", as used in industry today, is applied rather loosely. Generally, it refers to pressures that are higher than those encountered in most industrial processes although no definite limits are normally stated. For the purpose of this talk I should like to set rather arbitrary limits to the term "high pressure", and in ab-solute figures this would be the range from 1000 psi to perhaps 40,000 or 50,000 p.s.i. The scope of high pressure technology is very broad, and it would take more time than we have avail-able here today to cover fully even one aspect of the field. Therefore, I should like to discuss just some of the techniques used and problems en-countered in high pressure operations. Research work into the high pressure region dates back about 150 years, but it was not until 1910 that the first commercial application of high pressure technology was made in the production of ammonia.

Jan 1, 1962

By C. H. Johnson

This paper on the out-and-fill method of mining is one of a series on mining methods published by the United States Bureau of Mines. It has been compiled chiefly from recent publications of the bureau describing in detail mining methods and costs at various mines. Other sources of information were the technical press, the Transactions of the American Institute of Mining and Metallurgical Engineers, the Mines Haudbook, and company reports. References other than those mentioned in Table 1, which lists the mines entering into this discussion and gives general data regarding them, are given in the body of the paper. The authors wish to acknowledge the kind assistance of many operating officials, either through correspondence or in the course of numerous visits to their mines. DEFINITION OF CUT-AND-FILL STOPING The out-and-fill method of stoping is that method in which relatively small sections or slices are taken successively from the lower surface of a block of ground by open-stoping methods, the broken ore being removed and each section filled with waste material before the next is mined. This definition excludes shrinkage stoping, even with subsequent filling; it excludes square-set and fill methods; it excludes the Mitchell slice method, which may be classed as underhand square-setting; it excludes the systematic use of stull sets and filling, which is a variation of square-setting; it excludes any method involving the caving of the ore, walls, or overburden during the process of extraction, although caving may be allowed to take place when the waste fill is withdrawn for use in other stopes; and it excludes any open-stope method without filling. Through variations, which will be discussed later, the cut-and-fill method merges into shrinkage stoping, open stoping, or square-setting. The use of casual timber support, such as props, stulls, or timber cribs for holding up weak portions of the back does not constitute a change from cut-and-fill to square-set mining.

Jan 1, 1933

By H. W. C. Prommel

The increase in the price of gold in 1933 was the cause of starting many activities in gold prospecting and mining; it led to investigations of many of the so-called desert placers in the Southwest, which heretofore had not been deemed of commercial importance. Among these, attention was called to some of the gravel beds in the vicinity of the Randsburg-Atolia mining districts of Kern and San Bernardino Counties, Calif., in which gold and scheelite, (calcium tungstate, CaW04) were said to be present. Following a partial sampling and testing of the gravel, large-scale operations were begun in 1935. During the same year more detailed sampling and testing of the gravel beds were done by the author. During 147 days, 1,239 test holes 28 inches in diameter were drilled; their total depth amounted to 16,705 feet. These test holes furnished 2,495 samples of an average volume of 1.0583 cubic yards bank run each; all of the material was run through a sample mill constructed on the property. Original and rather unusual sampling and testing methods had to be used; milling and mining methods for large-scale operations also offered difficulties. The primary purpose of this drilling and sampling campaign was to determine, over a large area, the amounts of gold and scheelite recovered by placer methods such as were already in use on the property. This paper describes sampling and testing methods employed by the author during the 1935 drilling campaign. LOCATION The gold and scheelite placer deposit is in the Atolia tungsten mining district about one-half mile west of the small mining town of Atolia and about 5 miles south of Randsburg in the Randsburg gold-mining district. The deposit lies near the foot of the Rand Hills, in the Mojave desert. The territory is served by hard-surfaced roads from the north and south; Los Angeles is 150 miles to the southwest. A branch of the Southern Pacific Railroad passes within 5 miles of Randsburg.

Jan 1, 1937

By S. Gajardo, E. Valdés Guerra

Together with Sociedad Punta del Cobre S.A. (Pucobre) and Orica, we are carrying out a study of alternatives for methodology of excavation in Slot Up Raises from actually built with Blind Hole (BH) to drilling and blasting (DB) methodology. The study is part of the permanent search for innovation, the use of technology and the reduction of mine operation costs. This application aims to optimize the Sub Level Stoping method, which has historically been exploited at Pucobre. Using a new variant of the method “Open Stoping”, through the initial development of ascending blind raises using a pilot drilling of a bore hole, with the objective of eliminating the upper level in order to excavate the free face opening. This industrial test aims to replace the mechanized BH Up Raise of 1.5m (4.9 ft.) in diameter and 30m (98.4 ft.) high, with a Up Slot Raise considering two separate blasting events, using different technological enablers, as detailed below: accuracy drilling with relief holes of 254mm (10 in.) diameter, high viscosity bulk emulsion, wireless initiation system and high-strength injectable bulk resin. Considering the importance of the success of this application, a DB diagram was defined to allow the opening of the up raise in two blasting events, separated by intermediate stemming deck located at the same level at a height of 15m (49.2 ft.) from the collar, using high-strength injectable resin. The first blasting event considers the first section from the collar to the first 15m (49.2 ft.), using wired electronic initiation that is detonated on the first day. A second event blasts the section from 16.5 to 30m (54.1 to 98.4 ft.), using a wireless initiation system, as, it has no physical connection, is blasted on the second day after the extraction of the material resulting from the first event. For greater precision, the design of the explosive charge configuration and initiation sequence is made, adjusted to the measurements of trajectory deviations of the actual ground drilling and is also considered for the control of the explosive charge configuration with high viscosity bulk emulsion. This application improves the profitability of the mining business by generating savings through the change of Blind Hole methodology, estimating a savings of more than 75% per Up Slot Raise

Jan 1, 2024

By G. R. FITT, S. R. B. Cooke, C. W. Davis, V. H. Gottschalk, C. G. Maier, C. E. Wood, R. S. Dean, S. B. THOMAS, John Gross, E. P. Barrett, T. L. Joseph

Lack of funds has prevented publication of much of the metallurgical work of the Bureau of Mines during the past 2 years . The present progress report covers studies in the direct production of iron and steel . The experimental work was carried out in cooperation with the universities of California , Minnesota , and Missouri . Complete reports will be published when funds are available .

May 1, 1934

By S. U. Baltuch, E. G. Baltuch

"Ventilation in process buildings is key to proper mill function. Correctly engineered systems to evacuate surplus thermal energy from process areas allow optimized rates of air change, thus assuring the good functioning for the lifecycle of the process while demonstrating conformity with occupational hygiene standards. Computational fluid dynamic simulations, coupled with traditional calculations and physical modeling, can demonstrate to end users and assist engineers in the optimization of mill ventilation, reducing total installation costs while assuring that the proper solution is in place for the complete lifecycle of the process equipment. Results have been fully implemented on a number of steel mill and aluminium smelter applications and we continue to study, optimize, and innovate as new tools become available to provide the best possible engineered solutions for particular applications. INTRODUCTIONThe objective of this research project is the development and implementation of modern approaches and computational fluid dynamics (CFD) simulation in the engineering of green ventilation of hot process buildings. This will assure the predictive performance and improve the quality and ease of construction of industrial gravity ventilation equipment, along with the adjunct hot process buildings, while lowering the overall project costs and time to completion.In order for a hot process building, such as a steel mill, to properly function, heat must be extracted from within. This is accomplished by having air inlets at the bottom of the building and outlets at its apex. The reason for this is to maximize the potential chimney effect. When using stack (buoyancy) effect ventilation, the process heat becomes the driver. Therefore, increasing this distance (height) improves the ability of the heated airstream to utilize basic gravity for acceleration of the heat/air flow, allowing a regular number of air changes per hour while ensuring that the process environment remains weather resistant under normal operating conditions.This process has been understood since the time of King Charles I of England, who decreed in 1600 that buildings should have 10 foot ceilings and that windows should be made taller rather than wider to allow better smoke extraction.Figure 1 is a painting of the Bethlehem Steel Works in the 1860s, where the concept of air inlets and penthouses on the roofs for air outlet was already being put into practice. Figure 2 is an early photograph of the Pittsburgh Steel Works."

Jan 1, 2012

By Iván E, Alex Araya Jofre, Jean Guiroux Toro, Eduardo Valdés Guerra

Currently, it is important for companies to have controlled mining operations and adhere to production schedules. To achieve this, one of the key factors is maintaining high reliability in the P&T process, primarily the opening of ore stope, which could be delayed due to any unplanned or uncontrolled problem. These ore stope opening processes, whose main activity is generating free face, are a very important pillar for future mine planning. The possibility of ensuring their opening brings a series of downstream benefits: safety, economics, productivity, and compliance and adherence to plans. The process under discussion consists of developing free faces in a single blasting event. This will help us leverage greater reliability for overall production operation plans, reduce construction times, and open up opportunities for downstream improvements in the production process, considering technical factors in P&T designs. This study presents a developed methodology and shows the results of its implementation in ten (18) single-event free face blasts. The analysis includes cavity geometry, geology, rock qualities, drilling deviations, and the blasting strategy implemented for each event. The methodology used considered material fluffing processes, the actual drilling trajectory, the initiation sequence, QA/QC during explosive loading, monitoring instrumentation (vibrations), and VOD recording, among others. As a result, out of a total of 18 free-face events blasts in a single event, 16 were successful and two achieved 90% efficiency, reducing the stope's production start-up time by 50% compared to current operations. By implementing free face blasting in a single event, there are savings in operating costs, increased productivity of the mining equipment, and improved adherence to production plans. For applications with greater heights of free faces, where blasting cannot be carried out in a single event, we should consider performing them in two stages using wireless detonators already available on the market for mining operations.

Jan 26, 2026

By W. L. Saunders

(Wilkes-Barre Meeting, June, 1911.) I. INTRODUCTION. IT is now generally admitted by experts that at least so far as rapid progress is concerned the Alpine system of tunnel-driving is superior to any other. This is perhaps natural in view of the record of experience in driving tunnels through the Alps. These great mountain-chains cannot be treated in the ordinary way by shaft-sinking and driving headings, thus multiplying the points of attack. The work must be done from the ends only, hence speed in driving is of the utmost importance; and, as necessity is the mother of invention, the concentration of effort to make progress has resulted in an organization and in mechanical appliances that have produced results so much in excess of the usual practice, even in America, that a discussion of the subject in detail should be of much value to the engineer and contractor. The first Alpine tunnel was the Mont Cenis, length 7.5 miles, driven with a progress that averaged about 7.75 ft. per day. Next came the Saint Gothard, 9.5 miles long, 18 ft. per day; Arlberg, 6.5 miles long, 27.25 ft. per day; Simplon, 12.25 miles long, 36 ft. per day. The figures represent progress when driving from two headings, so that by dividing them in two we get the daily single-heading progress. The latest of the Alpine tunnels is the Loetschberg, now being driven. In this work the world's record has been beaten by a single day's record in one heading of 36 ft. and by an average daily record in. one heading of 29.5 feet. The Alpine range forms a natural barrier between a large section of northern and southern Europe. This range extends from the southeast of France to the frontier of Hungary, between Italy and the plains of southern Germany. The contour

Jul 1, 1911

By S Steffen, S Talu, J Poulsen, G Watt, A van As, J S. Ooi

The economic success of cave mining projects is significantly influenced by the secondary fragmentation size distribution of the caved orebody and making the fragmented ore available for extraction. If the cave does not propagate as predicted, it may lead to stalled cave growth and/or localised preferential caving. This can cause significant ore loss and the inclusion of excessive waste in draw columns, both of which damage the economic value of the project. Uncontrolled caving can have severe consequences for the safety and economics of mines. Such safety risks include air blasts due to the formation of excessive air gaps and damage to infrastructure due to surface subsidence. Monitoring the cave-back delivers critical feedback that is required to exert control over its propagation and reduce the likelihood of adverse consequences. Current methods for monitoring cave propagation include access through open holes, microseismic monitoring systems, time domain reflectometers and extensometers. All of these monitoring systems rely on stable holes for installation and ongoing data collection. However, cables in holes often get sheared due to ground movement in the seismogenic zone well ahead of the cave front, rendering the systems useless. To resolve this issue, Elexon Mining, with the support of Rio Tinto, developed the Networked Smart Marker system, which is based on Elexon’s Smart Marker technology. This system provides a more robust and versatile alternative to other cave monitoring systems as the data is transmitted wirelessly through rock, and thus is not vulnerable to hole shearing/dislocation experienced with current cave monitoring systems. Installations at the Argyle block cave have proven that the Networked Smart Maker system can continue to provide information on the cave-back’s location long after all conventional monitoring systems have failed. This paper summarises the findings from these installations and highlights the benefits for all geotechnical monitoring systems reliant on the stability of drill holes to remain functional.CITATION:Steffen, S, Poulsen, J, Van As, A, Talu, S, Watt, G and Ooi, J S, 2016. Wireless system for monitoring cave-back propagation, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 251–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Caterpillar recently held two, two-day demonstration programs for its mining customers. The event, billed as MineDemo by Caterpillar, consisted of two sessions held on consecutive weeks at the company's Tinaja Hills proving ground south of Tucson, AZ. The program included several classroom sessions that focused on Caterpillar equipment applications, including the VIMS (vital information management system) and the CAES (computer-aided earthmoving system). Also included were field demonstrations and the opportunity to test drive mining-related heavy equipment, including dozers, trucks, graders, shovels and loaders. Featured at the event were the recently upgraded 785, 789 and 793 C-Series trucks. Caterpillar recently announced the availability of the 136-t (150-st) 785C and the 177-t (195-st) 789C. The upgraded haulers have replaced the respective B-Series models. The 218-t (240-st) 793C was introduced in 1996. It, too, has been upgraded but retains the C-Series designation. While attending the press event, the author had the opportunity to test drive the 793C at the Tinaja Hills test site. It was amazing how well the machine handled. The operation was smooth and the braking system was precise. The cab was extremely comfortable. To see a C-Series truck in action, the author also visited Newmont Mining's Mesquite Mine, located in Cali¬fornia, across the border from Yuma, AZ. The Mesquite Mine operates a new model 785C truck. At the mine, temperatures have been measured as high as 58° C (138° F) in the pit. Needless to say, the ability to operate dependably in extreme heat is an important consideration for the mine operators. An interview with the driver and later with management confirmed that the 785C has worked out well. The driver praised the comfort of the cab and the ease of operation. Management reported significant fuel savings and was impressed by the truck's maintenance features.

Jan 1, 1999