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By J. Perlacia

"As the bulk handling sector continues its transformation to Industry 4.0, the mining industry, and its harsh working and environmental conditions, provides a perfect spot to study the feasibility of remote analysis and maintenance of the components used for bulk handling. The most important and expensive tools have been adapted to the digital era in recent years, from remotely controlled haul trucks to monitored conveyor belts.However, the big items of the installations rely on smaller parts that have been leftaside, mainly due to the difficultyof adapting them to the Internet ofThings (IoT).The paradigmatic example is the lack of monitored rollers, while all the other components of the conveyorbelt installations (the belt itself, motors, drums, etc.) were monitored some time ago. The main problem is that a failure of a single roller can cause the stoppage of the entire conveyor, due to possible damage to the belt. Thus, the implementation of an integral monitoring system of all the components of the conveyor is a must.The research and development department of ULMA Conveyor Components has been working since early 2012 on the development of monitored rollers, testing all the problems until their final installation in different demanding conditions, from the extreme heat in Australia to the freezing cold of Norway. All the tests have been done under actual working conditions, in real installations and have provided valuable knowledge in the identification of problems, their solutions and the final advantages of a roller monitoring system.Background and current stateThe malfunction of a single roller in certain conveyor belts can force the standstill of the entire installation until its replacement, due to the risk of greater and more expensive failures, such as a rip in the belt. In the case of a bulk handling installation, where a continuous supply of material is necessary, an unexpected stop of one hour could result in huge economic losses."

Nov 1, 2019

By Brendan Demich, Joseph McGuire, Emily J. Haas

Near misses recorded and reported by workers can provide awarenessto the potential causes of injury and prompt safety management initiatives. Although most companies require near-miss reporting, it is unclear what the value of these reports are, if any, and how they influence subsequent actions or controls to reduce on-the-job risks. Researchers at the National Institute for Occupational Safety and Health (NIOSH) conducted a case study with an aggregates company in which near-miss reports were analyzed at each of their locations over an entire quarter during the summer of 2018. Within that quarter, workers recorded 249 near misses. Of those, 167 were valid near misses that occurred at work. Researchers coded the reports using a qualitative 5 × 5 risk matrix. Of the 167 near misses, 19% were deemed low risk, 25% moderate risk, 30% high risk, and 26% critical risk. Several patterns in the near-miss incidents were documented, including classification of incidents and common corrective actions referenced (i.e., elimination/substitution, engineering control or redesign, work process/procedures, and personal protective equipment). The analysis provides insight into ways that risk communication and management programs can be improved to reengage workers and their situational awareness on the job.

By Laura Suarez, Jörgen Kajberg, Pär Jonsén

How does an investigation into the breakage characterization of electric arc furnace (EAF) manganese slags contribute to a more responsible usage of resources throughout the life cycle of steel products and reduction of carbon emissions? The main goal of this study is to increase the knowledge on the mechanical response of manganese slag to open the potential of pyrometallurgical residues to become secondary material in industrial applications such as infrastructure construction, fillers, binders and soil stabilization, among others.

Mar 1, 2024

By J. H. East

THE RIFLE, COLO., oil-shale project of the Bureau of Mines was a facet of the re-search and development activities conducted under the Synthetic Liquid Fuels Act (Public Law 78-290) of April 5, 1944. The principal objectives were to devise efficient methods to mine and retort oil shale and to refine shale oil into usable products, at a total cost low enough that shale oil could supplement the domestic supply of petroleum at competitive prices. The Rifle project included three major divisions: (1) Mining, (2) retorting, and (3) refining. The major functions of the mining program were to supply oil shale to the retorts, to devise mining procedures, and to develop an under-ground-mining method by which oil shale could be produced safely at an unusually low cost per ton. The selected mining procedures and direct mining costs were demonstrated by sustained test runs.

Jan 1, 1964

By M. Drozd, A. Ibrado, P. Butcher

While effective in treating refractory sulfide ores, pressure oxidation leaves carbonaceous matter unscathed and able to adsorb gold from cyanide solutions. Barrick Goldstrike's strategy to mitigate this problem is to minimize contact between dissolved gold and native carbon in advance of the carbon-in-leach (CIL) process. Measures currently in use include limiting carbonaceous matter in the plant feed by meticulous blending of ore, controlling the degree of oxidation in the autoclaves and blinding native carbon surfaces with lauryl sulfate. The presence of residual cyanide and thiocyanate in the process water remains to be a cause of premature gold dissolution and loss of gold by adsorption on carbonaceous matter. This cyanide is introduced by water that is recycled from the tailing pond. Of several treatment options considered, oxidation by peroxymonosulfuric acid, also known as Caro's acid, is deemed to be the most effective. Laboratory and pilot plant tests show that Caro's acid can oxidize free cyanide, weak¬acid-dissociable (WAD) cyanide and thiocyanate, resulting in significant improvements in gold recovery downstream. The process requires Caro's acid at 125 % of the stoichiometric requirement and pH in the range of 9.5 to 10 to accomplish the desired destruction in about twenty minutes. A cyanide destruction plant is currently being designed and construction should be completed by the end of 2005.

Jan 1, 2005

By Eleanor Abshire

This bibliography is the second in a series that covers the current technical literature relating to the metallurgy of zirconium. The rapid advance in zirconium technology makes it mandatory that abstracts be prepared and compiled as soon as possible to have maximum value; therefore, the information in this volume is not arranged chronologically. As a service to research and production groups, succeeding bibliographies will be issued as new acquisitions accumulate in the Zirconium Information Center sponsored by the Department of the Navy, Bureau of Ships and the Bureau of Mines at the Bureau's Northwest Electrodevelopment Laboratory, Albany, Oreg. The initial volume, Information Circular 7771, Bibliography of Zirconium, covering 969 abstracted reports and 645 United States and foreign patents, was published in April 1957.

Jan 1, 1958

By Michael P. Amsden

"THE ECSTALL CONCENTRATOR is situated adjacent to Highway 101 and the Ontario Northland Railroad, 15 miles east of Timmins, Ontario. Ore is delivered to the concentrator by rail from the mine, which is 17 miles northwest of the plant. Power and fuel are obtained from the hydro and natural gas lines which pass close to the plant site. Water is obtained from the Frederickhouse River, 6 miles east of the concentrator. The main concentrator building is a large structure 500 by 640 feet by 90 feet high and contains facilities for fine crushing, crushed ore storage, grinding, flotation, tin recovery, concentrate handling and reagent handling. Located in the same building are the machine shop, warehouse, metallurgical laboratory, pilot plant, men's change room, sample preparation area and an assay laboratory. The general concentrator layout is shown in Figure 47. Originally designed to handle 9,000 tons per day, the concentrator now treats 10,000 tons per day. Two different ore types are processed by selective flotation in three individual circuits to recover copper, lead and zinc concentrates. In 1973, another circuit was added to recover pyrite and tin concentrates from the combined zinc tailings of the three main circuits."

Jan 1, 1974

By D. H. NETLAND

DURING the year 1907 an investigation of the Clinton formation in New York has been carried out under the direction of the State Geologist, and a full account of the results has been prepared for publication.1 The more important economic features of the report are summarized in the present paper. Previous knowledge of this, the type, section of the Clinton has been contributed mostly by Hall and Vanuxem in their reports for the Natural History Survey of New York, which were issued in their final form in 1842-43. Brief accounts of the ore-occurrences have been given by B. T. Putnam,2 J. C. Smock,3 A. H. Chester,4 and E. C. Eckel.5 Prof. C. H. Smyth, Jr.,6has discussed the origin of the Clinton ores in two papers, which, so far as the local occurrences are concerned, have removed all doubt that may have existed on that subject. Distribution of the Clinton Formation. The Clinton strata in New York State are restricted to a single belt, Which extends from the eastern central part to the Niagara river, which it crosses, and thence continues for some distance into the province of Ontario. The New York

Mar 1, 1909

By P. P. Kim, M. Tangstad, T. A. Larssen

"The kinetics of MnO and SiO2 reduction in SiMn slags based on Assmang/Comilog ore and HCFeMn (highcarbon ferromanganese) slag were investigated between 1500 and 1650°C under a CO atmosphere. The results showed that charges containing HCFeMn slag had relatively faster reduction rates than those without. The difference in the driving force for MnO reduction was insignificant among the SiMn slags at 1500°C, which implies a low contribution of the driving force for reduction rate. The slag viscosities were also rather similar, around 1 poise at 1500°C, which could not explain the different reduction rates. Instead, the different charges containing various sulphur contents are believed to give rise to the varying reduction rates. The estimated activation energies for MnO reduction were around 500–920 kJ/mol for charges containing HCFeMn slag, and between 250–300 kJ/mol for those without. Based on the estimated kinetic parameters, the considered rate models were able to describe the reduction of MnO and SiO2 in SiMn slags between 1500 and 1650°C. IntroductionManganese ferroalloys such as ferromanganese (FeMn) and silicomanganese (SiMn) are important ingredients in steel production due to the beneficial effects of manganese on the physical properties of steel. Mn enhances the strength, toughness, and hardness of steel products, and both Mn and Si are used as deoxidizers to prevent the development of porous structures (International Manganese Institute, 2014; Olsen, Tangstad, and Lindstad, 2007; Subramanyam, Swansiger, and Avery, 1990; Tomota et al., 1987).The thermodynamic background of manganese ferroalloys is well established (Olsen, Tangstad and Lindstad, 2007), but kinetic information is rather scarce, especially for the SiMn process (Tranell et al., 2007; Tore-Andre Skjervheim, 1994). The absence of kinetic information makes it more difficult to understand the reduction mechanisms of MnO and SiO2. It is not clear how different raw materials affect the SiMn process. The main metal-producing reactions in the SiMn process are described by Equations [1] and [2]:"

May 1, 2019

By Nasser Madani, SULTAN ABULKHAIR

The geological and geostatistical modeling of mineral deposits requires densely sampled drillholes that provide accurate and reliable hard data. Furthermore, quantifying orebody uncertainty through geostatistical simulation can allow mining engineers to assess long-term risk in mine planning. Nevertheless, ore deposits can sometimes lack dense drillhole information, reliable hard data with proper quality assurance/quality control (QA/QC), or sometimes both. This study is based on a coal mine located in the Republic of Kazakhstan, where an iron dataset is based on data from three newly drilled drillholes, and geological information comes from a massive collection of legacy drillhole data with no evidence of proper QA/QC. For this reason, a workflow was introduced to construct a representative training image from legacy data and stochastically model geological domains within these three drillholes using a multiple-point geostatistics technique. Once the geological model was obtained, a two-point geostatistics algorithm was applied to model the iron inside each geological domain. The direct sampling algorithm was chosen for modeling geological domains, and sequential Gaussian simulation for iron grade calculation. Both methods were extensively evaluated using different statistical tools and analyses.

Aug 1, 2022

By Louis J. Sousa

In November 1989, the U.S. Bureau of Mines sponsored a 2-day conference to stimulate thinking and discussion about changing materials technologies and implications for the Government's materials information programs. On the first day of the conference, speakers provided overviews of developments occurring in each of the major materials groups. Emerging technological developments, applications, economic and national defense significance, intermaterial competition, and potential market growth in advanced plastics, polymer composites, ceramics, metals, and electronic materials were described. In general, the speakers forecast advanced materials market growth rates in excess of overall gross national product (GNP) though high costs will tend to limit growth outside of aerospace, defense, electronics, medical equipment, and other typically high value-added businesses. On the second day, a wide range of speakers representing several facets of the materials community described how advances in materials technology are creating a need for new types of data, statistics, information, and analysis. Reflecting the speakers' broad range of organizational, professional, and personal perspectives, an array of information needs was identified. Most requirements, however, seemed to fall into one of five major categories: Federal materials research activities, material standards, market and economic information, health and safety, and public policy.

Jan 1, 1990

By Keith L. Harris

Surprisingly, real gross national product (GNP) surged at a seasonally adjusted annual rate of 4.3% for the first quarter of 1987 according to preliminary estimates made by the Department of Commerce, the highest rate in 3 yr and significantly above the revised fourth quarter 1986 rate of 1.1% (table 1). The spurt, however, was caused by an unusual $59.5 billion rise in inventories, mostly cars and trucks, and there was little support from other sectors of the economy. Motor vehicle inventories rose as consumers continued to tighten their purse strings--consumer spending declined 0.4% for the second quarter in a row. Nonresidential and residential fixed investment and government purchases of goods and services were also down from the previous quarter. The increasing cost of energy was the major factor in the jump to 3.696 in the rate of inflation, as measured by the fixed-weighted price index for GNP, and rising inflation also helped put a damper on consumer spending. The underlying good news was that the trade deficit shrank for the second quarter in a row as imports declined at an annual rate of 11.1%. Also, profits in the manufacturing sector rose strongly in the fourth quarter, and for the first time in 9 quarters, the primary metal industries became profitable (table 1). If one discounts the anomalous inventory growth, the bottom line is that the economy continues to grow at close to the expected 2.5% level experienced over the past 2 yr. Of concern over the next several quarters, though, is the impact of the large over- hang of motor vehicles inventories on the economy. EMPLOYMENT The civilian unemployment rate declined to 6.636 in March after remaining at 6.7% for the previous 3 months. Employment continued to expand in February and March, although growth was significantly slower in March than in previous months. The manufacturing sector, however, lost 24,000 jobs in March after gaining 46,000 in February. Three-quarters of that gain came when striking workers at USX Corp. and Deere & CO. returned to their jobs. Employment in the manufacturing sectors of direct interest to the mineral industries has generally been increasing for at least the last quarter, while worker hours for these sectors have been on the upswing since April 1986 (figures 1 and 2).

Jan 1, 1987

By Lawrence Addicks

T HIS has been a most momentous year in the annals of the Institute. We have been in the midst of a situation which, were it not for the convulsions of social unrest with which life is surrounded on every side, would have attracted the attention of the world at large. I do not refer to the desperate campaign for new members. That has gone on much as usual except that, this being leap year, the annual proposal to the M. & M. Society has been omitted. Nor do I refer to the desperate situation which we found in other directions, the spread of Bolshevism, the burning of the Engineers' Club, the fact that the selling of copper appears to have become one of the lost arts. No, I speak of the great question which has to be. settled once and for all, as to whether this great Institute should adopt simplified spelling. The whole trouble started in the ranks of the California Hysterical Society. It appears, while most of the San Francisco members can read and write, several of them cannot spell. It also appears that the Secretary, in editing the Transactions, has perhaps made just a little bit too much of a point of employing the correct Stoughton idiom. At any rate, the rebels filed an amendment to the constitution, and the stage was set for civil war, with perhaps more stress on war than on civil.

Jan 1, 1920

For its Hellyer project, Aberfoyle sought to establish a high degree of confidence in all aspects of the feasibility study. Accurate capital and operating cost estimates were an integral and essential part of the study. They were crucial to the evaluation of investment returns and competitive cost position. Both the capital and operating cost estimates were based on the comprehensive data available from exploratory mine development, pilot plant operation, detailed engineering design, and Aberfoyle's experience in the area. One of the principal project objectives was to maximise operating productivity and efficiencies and this created capital cost alternatives which needed thorough cost-benefit assessment. The estimated capital cost for construction and development was $90 million, and the project was completed virtually on time for $80 million. The first year's experience indicated that operating costs would settle to well within 10% of the estimates.

Jan 1, 1990

By Júlia Guimarães Sanches

O curso de Engenharia de Minas sofreu uma expansão, juntamente com todo o ensino superior no país, por volta de 2005. O objetivo do presente estudo é avaliar as características dos cursos do país e realizar uma comparação com cursos de outros países com grande produção mineral. Foi feito um levantamento inicial a partir de informações disponíveis nos sites do MEC, INEP e das universidades. Como complemento, realizou-se um questionário com os coordenadores dos cursos de Engenharia de Minas do Brasil. Foram compilados ainda dados relativos à estrutura curricular e carga horária dos cursos de Engenharia de Minas dos EUA, Canadá, Austrália, Chile e África do Sul. Em relação à comparação das grades curriculares com os cursos de outros países, observou-se que no Brasil o curso possui uma maior cara horária de Tratamento de Minérios em detrimento da lavra. Nos demais países estudados, o foco das disciplinas é a lavra, já que nestes países a área de Tratamento de Minérios é assunto de outras Engenharias.

Oct 30, 2017

By Eric Jacobs

"Building and operating tunnels has been a highstakes endeavor in terms of costs, complexity, safety and impact on contractors, owners and the public for a long time. There are many variables that need to be closely monitored and managed to construct a tunnel on-time, on-budget and safely. Once built, there are also many elements that need to be monitored and managed to operate a tunnel safely and efficiently.Fundamentally, the risks to the safe and efficient construction and operation of a tunnel are a function of the degree of harm and the likelihood of the harm occurring. From a cyber security perspective, risk assessments used to inform decision makers and support risk responses are typically based on identification of relevant threats; internal and external vulnerabilities; the impact that may occur given the potential for threats to exploit vulnerabilities and the likelihood that harm will occur. This article focuses on creating awareness of vulnerabilities associated with technology used in tunnel construction and operation and some of the challenges associated with remediation of these vulnerabilities. As we all know, technology has been evolving at an accelerating pace and infiltrating every aspect of our lives in new and often exciting ways. In the world of tunneling, sensors and systems that provide position and time have become accurate, rugged and cost-effective enough to come out of the research labs and into the equipment and systems used every day. There are many opportunities to employ connected computing devices and sensors to costeffectively capture, integrate and analyze key data with minimal latency to manage risk better, improve safety and avoid surprises."

Jun 1, 2019

By F. S. Wartman

This paper gives an account of the production of ductile-grade titanium powder in 100-pound batches by reduction of purified titanic Chloride with magnesium, grinding, leaching, and magnetic-separation of the reaction product. Apparatus, technique, and methods of controlling product quality are described and some data on operating costs are given.

Jan 1, 1949

By K. K. Kelley

The collection and correlation of thermodynamic data concerning substances of metallurgical interest have constituted one of the major activities of the Pacific Experiment Station of the Bureau of Mines, at Berkeley, Calif., for the past several years. Earlier bulletins (32, 33, 34, 36, 36, 37, 38) s in this series are entitled: (1) Contributions to the Data on Theoretical Metallurgy. I. The Entropies of Inorganic Substances; (2) Contributions to the Data on Theoretical Metallurgy. II. High-Temperature Specific-Heat Equations for Inorganic Substances; (3) Contributions to the Data on Theoretical Metallurgy. III. The Free Energies of Vaporization and Vapor Pressures of In¬ organic Substances; (4) Contributions to the Data on Theoretical Metallurgy. IV. Metal Carbonates--Correlations and Applications of Thermodynamic Properties; (5) Contributions to the Data on Theoretical Metallurgy. V. Heats of Fusion of Inorganic Substances; (6) Contributions to the Data on Theoretical Metallurgy. VI. A Revision of the Entropies of Inorganic Substances-1935; and (7) Contributions to the Data on Theoretical Metallurgy. VII. The Thermodynamic Properties of Sulphur and its Inorganic Compounds. The present paper collects and discusses thermodynamic data relating to metal carbides and nitrides, with the view of obtaining usable heat and free energy of formation relationships. Pertinent data on both classes of substances are difficult to obtain experimentally and consequently are extremely rare; it is therefore necessary in many cases, if equations are to be derived, to introduce certain approximations and assumptions. Lack of adequate means of checking results by utilizing data of different types, such as was done frequently in the bulletins dealing with carbonates and sulphates, are readily apparent to anyone who has made even a cursory examination of the available information. Consequently, some of the relationships derived undoubtedly will be found to be inaccurate when more or better data become available. Nevertheless, in view of the importance of some of these substances, it appears worth while to consider the information available at present and to attempt the formulation of as complete a

Jan 1, 1937

By G. A. Apell

"SUMMARYThe quality of Moose Creek coal is considered superior to that of any now being produced in the Matanuska field of Alaska. In rank it is classed as roar coking high-volatile B bituminous coal.At present the Moose -Creek mines are accessible from the Glenn highway by 6 miles of well-maintained gravel road. The nearest railroad loading point is Moose Creek siding; 7 miles by road from the Buffalo mine. Palmer, 12 miles south of Buffalo mine, is the nearest town. Anchorage is 50 miles south of Palmer by road and-railroad.Core drilling and trenching by the Bureau of Mines revealed 2,375,500 short tons of coal in the Buffalo series on the Buffalo Coal Co. leasehold. Of this, 514,200 tons is considered measured coal and 489,900 tons indicated coal. Existence of deeper beds over the same length increased the tonnage of coal of all categories to 3,279,300 tons. The property has an assumed life, of 16 to 22 years, depending on the number of beds mined, based on an output of 500 tons of coal a day and 100-percent recovery. Coal from some of the beds car be marketed without washing however, a washery is necessary if all beds are mined. Beds in the Buffalo series not mined in the ""first mining"" will be irrecoverable at any later date.The Bureau of Mines completed exploration of approximately one-third of the local coal-bearing areas during 1943. Knowledge gained from this work makes it possible to investigate the rest of the area by drilling an estimated additional 5,000 foot of hole."

Dec 1, 1944

By I. Satola, J. Aromaa

In this work we have reviewed methods to classify corrosivity of ground waters. Weight loss and stress corrosion cracking (SCC) corrosion tests have been done for rebar and steel strand. No clear indication of SCC was found. The application of tensile stress to 85 % of yield strength increased general corrosion rate significantly in very corrosive waters. The effect of corrosion protection on the axial behavior of steel strands was determined by double pipe axial tests with different embedment lengths. The results showed a significant difference on behavior between epoxy-coated steel strands, galvanized steel strands and plain steel strand. Dans la présente étude, nous avons passé en revue des méthodes permettant de classifier la corrosivité des eaux souterraines. Des tests portant sur les pertes de poids et sur la corrosion FCC (la fissuration par corrosion sous contrainte) ont été effectués pour les barres d’armature et les torons. Aucune indication nette de FCC n’a été constatée. L’application d’une contrainte de traction allant jusqu’à 85 % de la limite d’élasticité a accru de manière significative la vitesse générale de corrosion dans les eaux très corrosives. L’effet de la protection contre la corrosion sur le comportement axial des torons en acier a été déterminé au moyen de tests axiaux à double tube avec des longueurs d’enrobage différentes. Les résultats ont mis en évidence une différence significative quant au comportement entre les torons en acier à revêtement époxy, les torons en acier galvanisés et les torons en acier standard. In dieser Arbeit haben wir Methoden geprüft, die korrosive Wirkung des Grundwassers einstufen. Gewichtsverlust- und SCC-Korrosionstests wurden für Stahlstäbe und Drahtlitzen durchgeführt. Es wurden keine sicheren Hinweise auf Spannungsrisskorrosionsbrüche gefunden. Bei Anwendung einer Dehnbelastung von 85 % der Streckspannung bzw.Ergebnisstärke stieg die allgemeine Korrosionsrate in stark korrosivem Wasser deutlich an. Die Wirkung des Korrosionschutzes bei axialem Verhalten von Stahldrahtlitzen wurde durch axiale Tests an Doppelleitungen unterschiedlicher Versenkungslänge determiniert. Die Ergebnisse zeigten im direkten Vergleich von epoxidbeschichteten, galvanisierten und normalen Stahldrahtlitzen beachtliche Unterschiede im Verhalten auf.

Jan 1, 2003