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By CARLE R. HAYWARDC

BEFORE discussing this subject it is necessary to define somewhat the meaning of the tern metallurgical.. When I was a student at M. I. T. ore-dressing was not thought of as metallurgy in any sense of the word, but it was considered as more closely allied to mining, enabling the miner to market an otherwise unmarketable product, or at least to market it to better advantage. Progress in ore-dressing has gradually allied it more closely with smelting, for at present the raw material received by the smelter is predominantly concentrates and smelting practice has been profoundly affected by the products of the concentrating mill. It is not surprising therefore that in many schools ore-dressing is frankly considered as metallurgy and although there may be some dissenting opinions it will be considered as such in this discussion. Twenty-five years ago at M. I. T. metallography was taught in a few optional lectures. This subject has developed rapidly and been expanded into the new and increasingly important field of physical metallurgy. To many metallurgists the -term metallurgy means only physical metallurgy. They know little or nothing about smelting and leaching and even less about ore-dressing. Having then broadened the scope of the term metal¬lurgy to cover ore-dressing, smelting, leaching and phys-

Jan 1, 1930

By F. Mielli

Over the last three years there has been an increase in mining congress and conferences focusing on water management. Water in mining is a key concern for mine managers and operations, and we are now seeing this operational dilemma escalated to the level it deserves. According to Frost & Sullivan research, mining water and wastewater treatment and its related technologies will be a U$3.6 Billion global market in 2016, which translates the importance of this issue. Looking at the current mining trends, some factors increased the importance of water in mining operations, including: ? Future mining investments will be located in geographical locations where water is scarce (water stressed areas) ? A decline in grade will increase the intensity of mineral processes and therefore increase the use of the water ? Increased sustainability and regulations will extend the control/monitoring of water during the entire mine life cycle representation of the mine water flow system. A water balance has several benefits/objectives in a mine operation: ? Mine planning/simulation of mining scenarios/climate change Production optimization ? Minimizing strategic and operational risks ? Social license to operate ? Water-smart mine planning ? Target: water neutral mines ? Benchmarking within and between sites ? Sharing knowledge/technology transfer ? Reporting/communications ? Permitting/Compliance

Feb 23, 2014

By William K. Brown

Are the results of an exploration program worth the cost? This is a question I suspect many of you are familiar with and, theoretically at least, it is an easy question to answer. The answer, of course, lies in comparing the future earnings stream the program is expected to generate, to the present value of the cost of carrying it out. While historical costs can be determined without much difficulty, estimating the value of a future earnings stream involves all sorts of assumptions regarding future costs, metal prices, inflation rates and an appropriate discount factor; and in the context in which the question arises, requires additional assumptions about mineral deposits which have yet to be discovered. As a practical matter, this kind of approach isn't likely to produce a very convincing answer; certainly not one convincing enough to satisfy a skeptical audience; nor one likely to temper the illusions of recent converts to mineral exploration, who are convinced that if enough money is spent, profitable discoveries will inevitably follow. Within broad limits, however, I believe it is possible to analyze the costs and results of gold exploration in the U.S.A. over the past 20 odd years in a useful manner. And while such an analysis is imperfect, it will provide some insight into this fascinating subject.

Jan 1, 1983

By T. A. Rickard

A severely technical article, however well written, can not be an agreeable form of literature. It suffers from the defects of its qualities. One defect is a congestion of language, due to a multiplicity of adjectival nouns. The sentences are packed with words of unpleasing sound, charged with complex ideas, crowding one another so closely that the phraseology moves like an ice-pack in Bering Sea or a log-drive in a river; the undercurrent of meaning may continue to move, but the surface is obstructed. This verbal congestion is made evident by ugly compoundings, many of which are adopted by the technical writer in the mistaken belief that they give directness to his statements. For example: A unanimously approved scheme "A scheme unanimously approved" The continuous temperature record "The continuous record of temperature" To stimulate interest in synthetic plant construction "To stimulate interest in the construction of synthetic plants " In smelters reverberatory-furnace firing with powdered coal has been practised for a decade. "In smelting, the firing of reverberatory furnaces with powdered coal has been practised for a decade. " A tar consumption of one pound per ton "A consumption of tar at the rate of one pound per ton'

Jan 1, 1931

By C. I. Godwin

"The relative-value (R-value), discrimination-factor (D-factor), and vector-ratio (V-ratio) method (RDVM) provides a geological knowledge-based statistical and geological-genetic interpretation scheme for geochemical data that enhances discovery in geochemical exploration. The practical advantage of RDVM is that it synthesizes geochemical features geologically related to ore-deposit discovery in three steps: reclassifying element concentrations using log-probability plots into R-values; calculating geologically defined D-factors from R-values; and determining V-ratios. D-factors are the sum of R-values, divided by the number of R-values summed. Based on the analyses selected, D-factors mimic rock or mineral deposit signatures. V-ratios refine interpretations of rock type and vector to orebody locations.RÉSUMÉ La méthode de la valeur relative (valeur R), du facteur de discrimination (facteur D) et du rapport de vecteurs (rapport V) (RDVM), fournit un schéma d’interprétation des données géochimiques basé sur les statistiques et les connaissances géologiques et la génétique géologique; ce schéma contribue aux découvertes en exploration géochimique. L’avantage pratique de la RDVM est qu’elle fait la synthèse des caractéristiques géochimiques reliées géologiquement à des découvertes de gisements de minerais en trois étapes : une reclassification des concentrations des éléments au moyen de courbes de probabilité logarithmique en valeurs R; un calcul des facteurs D définis géologiquement à partir des valeurs R et la détermination des rapports V. Les facteurs D sont la somme des valeurs R divisés par le nombre de valeurs R additionnées. Selon les analyses choisies, les facteurs D imitent les signatures de la roche ou des gisements minéraux. Les rapports V peaufinent les interprétations des types de roches et dirigent vers des emplacements de gisements."

Jan 1, 2016

By Patrik Bloemer

Reliable and accurate furnace bath level data during the melting process is invaluable for good decision making and furnace optimization, while obtaining such information rapidly and safely on a regular basis is of paramount importance. This paper shows how a melting process problem was identified as a concern, how a solution was sought and how a real-time measurement system was tested by simple modification to an existing temperature sampling manipulator. Also how, with furnace power on or off, taking reliable hot heel, fill and running levels could be used to assist melting control, aid decision making and improve safety.

Jul 30, 2018

By F. G. Miller, E. B. Wilson

In 1972, coal mine productivity was in steady decline and labor and maintenance costs were spiralling upward. Yet, despite this sad state of affairs, nowhere in the US at that time was there a comprehensive and coordinated coal research and development plan in the offing. The Bureau of Mines had not yet been charged with such a responsibility, and industry was content to rely on machinery manufacturers for innovations. It was during this period that Bethlehem Steel Corp. determined that a new approach to coal mining research was needed for the industry as well as for the company itself. After studying Bethlehem's own mining practices, the state-of-the-art of mining research elsewhere, and development work by manufacturers, a comprehensive research package was presented to company management in late 1972. The ideas and experience of many operating and management personnel in the company contributed to the formulation of the final plan as approved.

Jan 10, 1976

By T Tan, C P. Holmes, C E. Hartford

Transportation of iron ore from the mine to the plant is critical to business success. Ore from the mine may have to be transported across states, countries and even continents to get to the processing plant or export facilities, and ultimately to the client. Numerous transportation steps may result in potential logistical difficulties. Companies are continually seeking ways to increase production rates, decrease delivery times and reduce operating costs. Transportation cost is a major component of the total cost of mining iron ore and therefore requires effective use of transport systems.Bottlenecks in iron ore transport systems, due to material handling issues, can result in loss in profit in the order of millions of dollars per hour. Bottlenecks can be seen anywhere in the transport system where the desired flow rate cannot be achieved. These bottlenecks occur for various reasons such as increasing throughput in a transport system originally designed for a lower throughput resulting in plugged transfer chutes, changing material characteristics (eg finer material, increased moisture content), changing to a new type of material or blend that again alters handleability, or changes in operational philosophy due to equipment availability or process utilisation.Stockpiles may have limited live capacity such that an adequate amount of ore may not be readily reclaimed when required (eg to fill a complete train’s railcars). In bins and hoppers, material may discharge through a central flow channel resulting in the formation of a stable rathole, which can then collapse causing material to flood the downstream system and cause significant downtime for clean-up (eg railcars beneath train load outs). In transfer chutes, bottlenecks can be caused by pluggages or downtime required for the change-out of liners due to excessive wear. In ship loading, long settling or de-aeration time, or material exceeding its transportable moisture limit (TML) may result in further bottlenecks. These bottlenecks all have associated costs because of the need to address their causes and because of the lost opportunities for throughput.This paper will discuss how bulk material technology and proper understanding of material flow characteristics can be applied to mitigate bottlenecks. It will discuss how to predict potential bottleneck locations through a scientific method of analysis and evaluation to determine if an increase in throughput of an existing transport system is possible, as well as whether or not a new material will flow reliably through an existing system.CITATION:Hartford, C E, Holmes, C P and Tan, T, 2015. De-bottlenecking iron ore transportation from mine to plant, in Proceedings Iron Ore 2015, pp 393–398 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Robert H. Carpenter

Molybdenite mineralization occurs in the hood zone of the Questa mine aplite-porphyry intrusive, one of the three sil ica-rich intrusive5 occurring along the east-west trending Red River Trench that crosses the northerly trending Sangre de Cristo Mountains in north-central New Mexico. The Trench is located immediately north of the circular Gold Hill positive block between the Red River and Cabresto Creek drainages. The aplite-porphyry bodies intruded a mid-Tertiary volcanic section consisting of lower andesites, overlain by latites and rhyolites. They occur largely in the andesites and were emplaced mainly by metasomatism rather than by sloping. Hydrothermal alteration occurs both as blanket propylitization in the volcanics and sericitization and kaolinization in the porphyries and as halo-type alteration outward from veins and shear zones resulting in strong biotization in the volcanics and sericitization and kaolinization in the aplitic rocks. Mineralization consists of: ( 1) molybdenite- quartz veinlets; (2) banded molybdenite, quartz veins frequently with biotite and potash feldspar along the walls and occasionally with minor lead, zinc, and copper sulfides and with fluorite and carbonates when again reopened; ( 3) high grade molybdenite locally along shear zones; and ( 4) molybdenite paint along joint and fracture surfaces. The mineralization was associated with faulting that resulted from numerous periods of gravity adjustment along the Trench and was controlled by the major shear systems that trend northeast, east-west and north-south to northwest. Molybdenite has been well oxidized in nearsurface exposures to ferrimolybdite and the molybdenum-bearing ferric hydroxide, akaganeite. The oxidation of the abundant pyrite within the veins and shear zones and of the alteration pyrite in the volcanics resulted in a low pH environment under which the acid molybdate ion released by oxidation was fixed either in the ferrimolybdite or the akaganeite molecule in the veins and shear zones or in the soils. Little has been lost in the runoff.

Jan 1, 1968

By Albert L. Toenges, Louis A. Turnbull, Alonzo W. Quinn, J. M. Schopf, Arthur Neale, R. F. Abernethy

"INTRODUCTION The fuel requirements for industrial and domestic consumers in New England, in normal times, are supplied almost entirely by fuel oil, anthracite, and bituminous coal. A shortage of these fuels occurred during the war. This shortage was caused by (1) The diversion of oil to military uses; (2) the use of railroad and boat facilities that ordinarily would transport coal for the transportation of war materiel; (3) the inability of coal mines to apply the increased demand for coal which resulted from the conversion from oil to coal by domestic and industrial consumers; and (4) the increased demand of war industries for coal. Because of this critical fuel situation, an investiga¬tion was made of possible sources of fuel nearer to points of consumption in New England. Meta-anthracite, which is a satisfactory fuel for some purposes, had been mined in Massachusetts and Rhode Island many years ago. However, the introduction of freer-burning anthracite and bituminous coal into New England markets resulted in the abandonment of these mines.The coal mined in the vicinity of Portsmouth on Aquidneck Island, Newport County, R. I., had been used successfully for smelting copper ore and for fuel. It is reported that this coal is less graphitic than the material mined at Cranston near Providence, R. I. The coal is meta-anthracite and does not burn freely. However, improved equipment for burning coal has been developed, and if minable reserves of meta-anthracite should be found, methods of burning it probably could be devised.The purpose of this investigation was to determine sources of additional fuel. Since meta-anthracite mined at Portsmouth had been used with some success, an investigation was undertaken to determine the characteristics and continuity of the beds in this area."

Apr 1, 1948

By Bureau of Mines Staff

Coal research and related activities in 1964 by the Bureau of Mines resulted in many advances in the production, preparation, and utilization of this valuable natural resource. Mining research during the year was marked by work on hydraulic mining, coalbed degasification, mine drainage control, mine sealing, strip-mine rehabilitation, and quenching of mine-refuse fires. Bureau research continued to produce information leading to increased safety in underground mining. Such research included roof and rib control via bolting and bonding, pressure monitoring of coal and mine rock during mining operations, and development of safety devices for detecting conditions leading to roof falls. Other safety work was continued on methane detectors, coal-dust suppression, and mine venti lation equipment and techniques. Mine explosion and explosives research, mine equipment and materials, safety rule modernization, and safety education and training of mine workmen were continued. Coal storage and preparation work in 1964 ranged from freezeproofing of lignite for rail shipment, through washability studies of coals and washing equipment, to research on new ways to remove ash and sulfur from coal. Electric power production, which ,accounts for a major portion of the market for coal, received further study. Unique power generation systems, inc luding coal-burning gas turbine and megnetohydrodynamic generators, were intensively investigated. Conventional power systems were improved through continuation of work on furnace performance, powerplant stack gas purification, and engineering and boiler water service.

Jun 1, 1965

Approximately half of all the fuel energy used in the United states is now pro-vided by oil and natural gas. A persistent and rapid growth in energy demand during the last 3 decades has been absorbed largely by the liquid and gaseous rather than solid fuels. In 1948 the energy provided by coal was substantially the same as in 1920. Meanwhile, the use of oil and natural gas each had increased fivefold. On a per capita basis, the change is more significant. Coal consumption has dropped from about 6 tons per person to 4-1/2 tons, while oil has increased from 4-1/3 barrels to 14-1/3, and natural gas from 7,500 cubic feet to about 35,000. These facts would have only academic interest if the United States had unlimited supplies of all fuels. However, while the Nation's reserves of coal are adequate to meet our needs for centuries, those of oil and natural gas appear limited. It is obvious, therefore, that the security of our liquid-fuel position would be greatly enhanced if the supply could be based in an increasing degree on solid fuels, such as coal and oil shale, which make up more than 95 percent of our fuel reserves, instead of natural oil and gas. In addition, this would create new employment and help to stabilize the market for coal, which may be facing comparatively bleak prospects in the near future unless its position with respect to other fuels is improved.

Jan 1, 1950

By B. Simser, T. Butler

Glencore’s Nickel Rim South Mine, located in Sudbury, Ontario, Canada, is a primary/secondary blasthole operation with ore zones lying between 1,100 and 1,700 m below surface. One of the main benefits of the primary/secondary mining method in high stress ground is that up to 50% of the mining will take place in secondary stopes that should be in a yielded rock mass state. Every future secondary mining stope begins as a primary stope abutment pillar. As with many mines, the stress loading history and rock mass conditions can vary considerably in space and time. Safe mining practices cannot allow for an assumption that the planned secondary stopes are indeed yielded. An incorrect assumption can result in mining development and stoping taking place in high stress ground rather than the expected yielded rock mass conditions. This can result in higher levels of seismicity than expected and incorrect ground support recommendations in areas where workers could be exposed. Seismic monitoring is the mines’ premier tool to track the actual rock mass response to mining. Yielded zones have a reasonably clear seismic signature/pattern over time that is visible in the collected data. The ability to accurately locate small magnitude seismic events can help define and delineate different stages of rock mass failure. The vast majority of the seismic data recorded by the microseismic monitoring system is below moment magnitude (Mw) 0.0. Examples are provided showing how small seismic events (Mw < -1.5) can help provide feedback from the rock mass deformation that allows the ground control engineer to gain a better understanding of how the rock mass is responding to mining processes.

Apr 26, 2022

By John P. Wagner

The details of a three-phase study (total time period of 12 months) entitled ?Fire Alert Systems for Metal and Non-Metal Mines,? are presented. Phase 1 consists of a state of the art survey on fire detection devices and gas sensing techniques. Phases 2 and 3 include laboratory screening and systems concepts testing on various detectors classified as products of combustion, optical view-field and contact (or thermal) types under incipient and flaming combustion conditions. Recommendations for a mine fire detection system to protect shaft, sealed off or mined out (from spontaneous combustion of sulfide containing ores and cellulosic materials), and fuel storage areas are also included. me principal problem area noted during Phase 1 study is the high expected occurrence of false alarming of products of combustion detectors (POC") subjected to normal mining operations---diesel vehicles and equipment and shot firing or blasting operations. Simultaneous gas sensing of either the ratio of CO/NOx or CO2/NOx with detection of one or more fire signatures (smoke, radiant energy, or heat sensing) is the recommended approach to discriminate against these operations.

Jan 1, 1975

By Paul M. Tyler

This paper presents one of a series of digests of foreign mining legisla- tion and court decisions that is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Switzerland has been prepared from the best information available in ashington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consuler officers, to whom it is being referred through the courtesy of the Department of State. Sitzerland is a small country in which little mining is done, yet it has a voluminous body of mining legislation. There are two salt-mining districts in Switzerland; that at Bez, Canton of Vaud, belongs to the Canton but the deposit is worked by a private company; and those at Schweizerhalle, Rheinfelden and Ryburg are worked by a joint stock company formed by the Cantons interested. Iron ore is mined at Gonzen, Canton of St. Gallen, and large beds of gypsum are worked, mainly for domestic consumption. In general, however, although many kinds of minerals are said to have been found in Switzerland, mining operations are irreguler end relatively unimportant. Even during the world war only about 2,500 persons were employed in mining establishments and most of these were in under round stone quarries. On the other hand, the republic comprises 22 Cantons, of which 3 are divided, making 25 units, and in the absence of generel Federal legislation, each of these units virtually has its own distinct mining la Under these circumstances, it is obviously inadvisable to review the mining lars of Switzerland in the same detail as those of other countries which Lave been digested in this series. For the lars of individual Cantons, as well as for a more comprehensive summary of the Swiss legislation as a whole, the reader is referred to a recent German publication." Many of the statements in the present paper can be traced to this source. Acknowledgment is also made of the brief analysis published by anot..er German authority..

Jan 1, 1933

This manual provides basic practical instruction on the inspection of driven piles. It covers the essential components of pile driving, such as the pile driving hammer, hammer accessories, the pile and soil, and frequently encountered test methods in an uncomplicated, yet knowledgeable, and practical manner. Insight is given into the methods of installing the foundation, dealing with the cranes which do the lifting, the hammers which do the driving, the leads that guide the hammer and pile, the compressors which provide the external power when required, and finally prevalent analysis tools and testing instrumentation and procedures which enable you, the Inspector, to do your job. This DFI Inspector&apos;s Manual for Pile Foundations will help the Pile Inspector who has limited knowledge of pile foundations. Perhaps this Inspector has been pressed into service at a moments notice; a few helpful hints and suggestions to him are desperately needed and he can look here for the basics. It is also useful for the experienced Pile Inspector as a reference guide. However, this manual is not a detailed check list of every possible scenario and detail which could ever be encountered. There are other sources available which give more detailed descriptions (and should be consulted by the Inspector when appropriate; a list of this additional reference material is provided and suggestions made in appropriate chapters of this text). The current manual is more a brief "textbook overview" with some of the more important aspects given at least some emphasis so that the Inspector has some direction and hopefully helps to produce a safe, yet economical, foundation.

Jan 1, 1997

By Peter Zhang, Todd Minoski, Gabriel Esterhuizen, Jack Trackemas, Berk Tulu, Morgan Sears

Longwall mining is a highly productive and efficient coal mining method used in the USA. During longwall retreating, the belt entry must be maintained stable, and any roof fall in the belt entry would jeopardize mine safety and substantially interrupt the continuous production of coal in the longwall face. Past experience of longwall mining has shown that belt entry stability was the greatest challenge in longwall ground control, and the occurrence of roof falls in belt entries was largely associated with high horizontal stress. To properly support the roof in the belt entry, it is important to understand how longwall-induced horizontal stress changes affect roof stability in belt entries and to strategically install supplementary support to prevent any potential roof falls. Researchers from the National Institute for Occupational Safety and Health (NIOSH) performed horizontal stress measurements in the immediate roof of the belt entries for two Pittsburgh seam longwall panels oriented unfavorably to high horizontal stress. Hollow inclusion cells (HICells) were installed in the immediate roof at the intersection in each of the belt entries, and stress changes were monitored as the longwall face was approaching and passing the intersection. Numerical models were set up to calculate the longwall-induced horizontal stress changes in the roof at the monitoring sites. With the verified model, investigations were made of how horizontal stress is concentrated and relieved in the belt entry roof near the face under different panel orientations. Both measurements and modeling results showed that high horizontal stress is concentrated in the roof in the belt entry within about 15 m outby the face when a longwall panel is unfavorably oriented to the major horizontal stress. The study demonstrated that longwall-induced differential horizontal stress can be used as an indication of the degree of horizontal stress concentration. Roof support strategies are discussed on how to maintain the stability of belt entry under high horizontal stress concentration.

Jun 14, 2022

By Frank Rieber

EVERYONE is familiar with the story of the poor Indian and his leaking tepee. He couldn&apos;t repair the leak while it was raining, naturally. And when it wasn&apos;t raining, where was the incentive? Even if this traditional Indian was apochryphal, his counterparts are certainly alive today, and operating on a world-wide scale. - A recent issue of the Wall Street Journal, for example, carried an impassioned letter from an old cocoa planter, who wants the world to know why the price of cocoa has gone skyrocketing. For years, he says, British and American interests have bought cocoa at the cheapest possible price and, incidentally, from growers willing to sell at that price. Between them, they didn&apos;t put enough money back into the business, either to fight disease in the cocoa groves or to plant new cocoa trees. Until new trees are planted and come into bearing, we will be paying exorbitant prices for our cocoa, and getting less of it.

Jan 1, 1948

The following situation was submitted as an ethics case study for inclusion in the Journal. To the best of our knowledge, they are based on actual circumstances encountered in the field. Blowing the Whistle Protecting Confidentiality or Doing the Right Thing? This case centers around a construction job and involves a contractor, subcontractor/blaster, and a farmer/homeowner who lives near the job site. It is essentially a study of professional ethics versus morality, our professional code of conduct versus what is right or wrong.

Jan 1, 2007

By John Relser

The production processes that are developed in the mining and minerals industry are manufactured to be exposed to very aggressive environments. Chemical, abrasion, and impact expose structures and equipment, steel or concrete, to a significant deterioration. This causes damage and adds high costs to operations that can be reflected in the destruction of equipment and structures in the arrest of the production process, which becomes very costly. Also, there is the potential for personnel accidents, which would require large sums of compensation for an employee, thus directly harming the image of the mining operation and company. Manufacturers of paints and coatings that have major centers for research and development (R&D Labs) distributed globally have developed high-tech products for durable protection from the elements for structures and equipment used in the mining industry. The difference between these paintings and coatings and what is normally known as conventional paints (e.g., those called domestic or decorative), is its chemical composition, structured around polymeric components that have highly resistant, chemical and physical properties to cope with extreme conditions to which they are exposed. With this, and only this, longer life of components can be achieved for equipment and structures used in the production processes of the mining industry. Today, in addition to the important features mentioned, some manufacturers of the paints and coatings dedicated to this highly modernized process have invested large sums of money in developing new products that add operational elements to the painting process. These coatings provide added value and significant performance to companies mining operations and that we can describe in three fundamental concepts:

Feb 1, 2014