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By H. Hearnden

Whereas in the past, ladles were simply a means of transferring molten products from furnace tapholes to points of discharge be they casting pans or waste dumps, the ladle is now becoming a more integral and versatile piece of equipment in the pyrometallurgical plant. The drive behind this development is the need for continuous improvement in performance where better, faster and cheaper means remaining competitive in the global market. This paper will explore the technologies available for the rendering of a costly and otherwise cumbersome piece of pyrometallurgical equipment more efficient and versatile in adding value to the final product. Essentially it all revolves around heat and more importantly the loss of it when tapping. The common practice is to move the molten product to its point of discharge quickly with the minimum of interruption to prevent skulling and hence the cost associated with clearing it. The advances in Oxy-fuel burners, AC or DC ladle furnaces, converters, gas purging and high velocity, bath injection systems has increased the versatility of processes and enhanced the potential for adding value to intermediate products through down stream practices such as granulation and atomisation.

Jan 1, 2004

By A. D. Davis

The historic Homestake Gold Mine at Lead, SD, was closed in December of 2001, after 125 years of operation. Since closure, the mine has been selected by the National Science Foundation as the proposed host site for the Deep Underground Science and Engineering Laboratory. Pumps in the 8000-ft deep mine were shut off on June 10, 2003. Post-closure flooding of the mine has resulted in rising water levels that reached the 5000-ft level in July of 2007. The rate of water inflow into the mine is about 750 gal/min. A plot of water level vs. time shows that the rise has not followed an exponential decay curve. When the pumps are turned on for dewatering, the rate of water-level decline will be monitored. Water in the Homestake mine contains arsenic derived from arsenopyrite. In samples of mine water, the median concentration of arsenic was below the surface-water aquatic life standard for beneficial use.

Jan 1, 2008

By J. Kretschmann, N. M. Smith, J. F. Brune, P. Goerke-Mallet

Coal production and coal use for electric power generation are diminishing worldwide. Germany will phase out lignite mining as well as lignite and hard coal-powered electricity generation by 2038. In the United States, coal production has dropped by more than 50% since 2006, including in key coal production states like West Virginia and Wyoming (EIA 2021). Closing mines and power plants across entire mining regions has significant socio-economic impacts. Existing industries must be focused on the post-mining economy by attracting new industries, and implementing job retraining programs for displaced workers, as former mining regions transition towards agricultural, industrial and recreational use. This paper examines the German “exit from coal” under the 17 UN Sustainability Goals and illustrates the complex procedures, interrelationships, risks, and rewards of the transition towards renewable energy sources, including wind, solar, hydrogen, and bioresources.

Mar 2, 2022

By Thomas T. Read

MINING, which is at least twenty centuries old, was at first, and long, wholly a practical art. Little more than two centuries have elapsed since the inception of the idea that general education and a knowledge of natural science would be of advantage to those engaged in the mining industry. Though schools of mining began to develop in Europe early in the eighteenth century the concept of educational preparation for technical conduct of the industry was slow in winning general acceptance in the industry itself. John Hays Hammond, in his autobiography, recalls that when he sought employment with a mining company after he had graduated from Yale and Freiberg he had to assure its executive, before being even considered for employment, that he did not consider that he had learned anything about mining. This was as late as 1880. Existence in the industry of a prejudice against education of the academic type is perhaps an explanation why inadequate provision has been made by the mining industry for the continuing education of technical employees after they enter employment, although engineering education prior to engaging in industry has now won general acceptance. I am familiar with the existence of "loop" courses for engineering graduates in metallurgical plants, of schemes for giving mining graduates "practical experience," and of the interest in vocational courses for workmen which sprang up in the period of labor shortage during and immediately following World War I (but which quickly died when the depression of 1921 again made experienced workmen available in sufficient supply), having been chairman of a committee appointed by the Mineral Industry Education Division to make a survey of existing provisions for post-employment training for engineers in our industry. The results of that survey, reported elsewhere, dearly indicate that it is inadequate as to amount; the aim of this paper is to present evidence for belief that it is also inadequate in quality. To avoid becoming too involved, no reference will be made here to post-employment vocational training for workmen, which is a subject differing so much from post-employment education for engineers as to require separate treatment. Neither will postgraduate education for metallurgical engineers be discussed, because a distinction must then be made between training for research work and for plant operation, whereas mining engineers engage almost exclusively in operations. Since the situation in the coal-mining industry has been discussed at several recent meetings, that also will be passed over, and what follows should be taken as a discussion applying exclusively to the metal-mining industry. PROFESSIONAL DEVELOPMENT In the operations field (both in mining and metallurgy) the work to which a beginner is assigned is seldom closely related to previous academic- education. The contrast is almost as great as between

Jan 1, 1941

By Thomas T. Read

MINING, which is at least twenty centuries old, was at first, and long, wholly a practical art. Little more than two centuries have elapsed since the inception of the idea that general education and a knowledge of natural science would be of advantage to those engaged in the mining industry. Though schools of mining began to develop in Europe early in the eighteenth century the concept of educational preparation for technical conduct of the industry was slow in winning general acceptance in the industry itself. John Hays Hammond, in his autobiography,1 recalls that when he sought employment with a mining company after he had graduated from Yale and Freiberg he had to assure its executive, before being even considered for employment, that he did not consider that he had learned anything about mining. This was as late as 1880. Existence in the industry of a prejudice against education of the academic type is perhaps an explanation why inadequate provision has been made by the mining industry for the continuing education of technical employees after they enter employment, although engineering education prior to engaging in industry has now won general acceptance. I am familiar with the existence of "loop" courses for engineering graduates in metallurgical plants, of schemes for giving mining graduates "practical experience," and of the interest in vocational courses for workmen which sprang up in the period of labor shortage during and immediately following World War I (but which quickly died when the depression of 1921 again made experienced workmen available in sufficient supply), having been chairman of a committee appointed by the Mineral Industry Education Division to make a survey of existing provisions for post-employment training for engineers in our industry. The results of that survey, reported elsewhere, clearly indicate that it is inadequate as to amount; the aim of this paper is to present evidence for belief that it is also inadequate in quality. To avoid becoming too involved, no reference will be made here to post-employment vocational training for workmen, which is a subject differing so much from post-employment education for engineers as to require separate treatment. Neither will postgraduate education for metallurgical engineers be discussed, because a distinction must then be made between training for research work and for plant operation, whereas mining engineers engage almost exclusively in operations. Since the situation in the coal-mining industry has been discussed at several recent meetings, that also will be passed over, and what follows should be taken as a discussion applying exclusively to the metal-mining industry. PROFESSIONAL DEVELOPMENT In the operations field (both in mining and metallurgy) the work to which a beginner is assigned is seldom closely related to previous academic education. The contrast is almost as great as between

Jan 1, 1941

By Thomas T. Read

MINING, which is at least twenty centuries old, was at first, and long, wholly a practical art. Little more than two centuries have elapsed since the inception of the idea that general education and a knowledge of natural science would be of advantage to those engaged in the mining industry. Though schools of mining began to develop in Europe early in the eighteenth century the concept of educational preparation for technical conduct of the industry was slow in winning general acceptance in the industry itself. John Hays Hammond, in his autobiography,1 recalls that when he sought employment with a mining company after he had graduated from Yale and Freiberg he had to assure its executive, before being even considered for employment, that he did not consider that he had learned anything about mining. This was as late as 1880. Existence in the industry of a prejudice against education of the academic type is perhaps an explanation why inadequate provision has been made by the mining industry for the continuing education of technical employees after they enter employment, although engineering education prior to engaging in industry has now won general acceptance. I am familiar with the existence of "loop" courses for engineering graduates in metallurgical plants, of schemes for giving mining graduates "practical experience," and of the interest in vocational courses for workmen which sprang up in the period of labor shortage during and immediately following World War I (but which quickly died when the depression of 1921 again made experienced workmen available in sufficient supply), having been chairman of a committee appointed by the Mineral Industry Education Division to make a survey of existing provisions for post-employment training for engineers in our industry. The results of that survey, reported elsewhere, clearly indicate that it is inadequate as to amount; the aim of this paper is to present evidence for belief that it is also inadequate in quality. To avoid becoming too involved, no reference will be made here to post-employment vocational training for workmen, which is a subject differing so much from post-employment education for engineers as to require separate treatment. Neither will postgraduate education for metallurgical engineers be discussed, because a distinction must then be made between training for research work and for plant operation, whereas mining engineers engage almost exclusively in operations. Since the situation in the coal-mining industry has been discussed at several recent meetings, that also will be passed over, and what follows should be taken as a discussion applying exclusively to the metal-mining industry. PROFESSIONAL DEVELOPMENT In the operations field (both in mining and metallurgy) the work to which a beginner is assigned is seldom closely related to previous academic education. The contrast is almost as great as between

Jan 1, 1941

By H. R. Wheeler

CREATION of a "committee on promotion of student interest in coal mining" has an encouraging implication for the coal industry. It is indicative that mining men, both in the field and in the educational centers, realize that the problems of the industry require the best talent available. Young men are being invited into coal on the premise that it needs them, that it offers opportunity for creative work and the realization of their objectives. In initiating a movement which purports to meet the objectives of any young man who spends four or five years of his life in college, the industry does so with a full realization of its obligations.

Jan 1, 1940

By Kenneth L. Cashdollar

The Pittsburgh Research Laboratory (PRL) of the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) conducted joint research on dust explosions by studying post-explosion dust samples. The samples were collected after full-scale explosions at the PRL Lake Lynn Experimental Mine and after laboratory explosions in the PRL 20-L chamber and the Fike 1-m3 chamber. The dusts studied included both high and low volatile bituminous coals. Low temperature ashing for 24 hr at 515°C was used to measure the incombustible content of the dust before and after the explosions. The data showed that the post-explosion incombustible content was always as high as or higher than the initial incombustible content. The MSHA alcohol coking test-was used to determine the amount of coked dust in the post-explosion samples. The results showed that almost all coal dust that was suspended within the explosion flame produced significant amounts of coke. Measurements of floor dust concentrations after LLEM explosions were compared to the initial dust loadings to determine the transport distance of dust during an explosion. All of these data will be useful in future forensic investigations of accidental dust explosions in coal mines or elsewhere. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health or the Mine Safety and Health Administration.

Jan 1, 2006

By Fred Fuchs

"Most deep foundation work is either unseen by the general public or viewed as an inconvenience in their daily lives. Hurricane Katrina changed that perspective for everyone in New Orleans — and many other people in the U.S. and abroad. The public and the government of south Louisiana, and the U.S. Army Corps of Engineers (USACE), all needed to restore trust in the system that protects their property and, more importantly, their lives. While much has been written about the failures of government agencies, in this case incredible solutions were devised and implemented despite daunting schedules and arduous conditions. These solutions were achieved through collaboration, and through the efforts of USACE, where the goal was to fi nd the most expeditious and effective design/build solutions. This disaster thrust the pile driving industry into the national spotlight. Boh Bros. Construction Co., L.L.C., along with numerous local and national heavy construction companies, subcontractors, material suppliers and government agencies, take pride in the milestones reached after Hurricane Katrina.The majority of New Orleans’ population lives below sea level. Historically, the city has been protected by a fl ood control system consisting of earthen levees and I-walls (steel sheet pile topped by vertical concrete wall). Rainwater is pumped out of the city over this protection system and into canals that feed into Lake Pontchartrain. On August 29, 2005, when Hurricane Katrina made landfall just east of the city, the levee system experienced a major failure of several I-walls lining the outfall canals, causing flooding of 74% of the east bank of the city. The counterclockwise rotation of the wind pushed the lake water onto the south shore, raising the level of water more than 10 ft (3 m). A failure of 450 ft (137 m) of floodwall lining the east side of the 17th Street Canal caused extensive damage. This breach prevented the use of the pump stations that outfall into the 3-mile (4.8 km) long 17th Street Canal."

Jan 1, 2008

By J. Shahabpour

"Abstract - Breccias with angular and rounded clasts of a late-mineralization, ""barren"" hornblende porphyry dike set within a comminuted matrix consisting of rock fragments and quartz, cemented by quartz and K-feldspar of hydrothermal origin is observed in diamond drill cores from the Sar Cheshmeh porphyry copper deposit. Studies of age relationship between vein types, phyllic-altered clasts and the breccia groundmass suggest that the brecciation is a late event. The breccia clasts record evidence of hydrothermal reaction between the clasts and fluids responsible for the brecciation.Formation of bornite, in the breccia clasts of the originally barren hornblende porphyry dike, and in the breccia matrix, along with the scarcity of bornite in the Sar Cheshmeh deposit itself suggest involvement of fluids which are later and of different composition from the fluids responsible for the known mineralization at Sar Cheshmeh. These later fluids may be related to a later plutonic event and suggest the possibility of a later, and concealed deposit."

Jan 1, 1994

By D. Limpitlaw

The origins of mine closure practice have influenced the way in which it is implemented by companies and regulators. Mine closure practices essentially started developing in the 1970s in countries with advanced economies and mature mining industries. In these settings, the emphasis was justifiably placed on restoration of the landscape and an attempt was made to return to the ?natural? pre-mining land cover. These practices continued to evolve and incorporated socio-economic and cultural aspects, especially after the Brundtland Report in 1987 and the subsequent Earth Summit in 1992. Today mining is increasingly occurring in remote parts of developing countries where there may be significant need for infrastructure such as roads, clinics, and schools. The costs of returning land to low (economic) value pre-mining use may be far greater than establishing a viable postmining land use that could potentially add value to the community and take pressure off sites for greenfield development elsewhere. Furthermore, natural resource limitations (such as topsoil availability) may limit the degree to which the historical land cover can be re-established. Establishing post-mining land uses may aid in mitigating the loss of employment that is inevitable when mines close. Stakeholder participation in establishing post-mining land cover and land use options is critical for long-term success. Similarly, third parties must be identified to support the development of the post-mining land use This paper draws on the experience of the authors in several developing countries and presents a case for maximizing re-use of mining infrastructure. The paper does not advocate the adoption of poor rehabilitation standards, nor or the wholesale destruction of land capability, but rather leaving key infrastructure in place for post-mining use that may support sustainable development.

Jan 1, 2014

By J Skousen, C E. Zipper

"Prior to the 1950s in the USA, surface coalmines were generally left without any reclamation. As government regulations advanced, mine operators were required to backfill the area and plant grasses or trees. After the federal Surface Mining Control and Reclamation Act (SMCRA) was passed in 1977 in the USA, mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after the mining. Common post-mining land uses in the USA are: agricultural uses such as prime farmland reclamation with crops, hayland and pasture, and biofuel crops forestry wildlife habitat building site development.Provisions and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were established. Post-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future.CITATION:Skousen, J and Zipper, C?E,?2014. Post-mining land use options in the Appalachian coal mining region of the USA, in Proceedings Life-of-Mine 2014, pp 153–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

By JURGEN KRETSCHMANN

The European climate and energy framework for 2030 is highlighting the reduction of man-made CO2 by increasing the use of renewable energy. In this spirit, Germany has decided to erase coal use as an energy source by 2038 completely. This strategy premises a feasible, responsible and sustainable post-mining management. The Research Institute for Post-Mining (FZN) at the TH Georg Agricola University in Bochum, Germany, has developed a holistic approach to meet post-mining challenges. In all efforts, the FZN aims to achieve the fundamental goals of the United Nations to deal with the resources of our planet responsibly and sustainably.

By Jürgen Kretschmann

The European climate and energy framework for 2030 is highlighting the reduction of man-made CO2 by increasing the use of renewable energy to mitigate climate change. In this spirit, Germany has decided to erase the coal use as an energy source by 2038 completely. Inevitably, this strategy promises a feasible, responsible, and sustainable post-mining management, because 200 years of coal mining have created numerous challenges necessary to tend to once the mining ends. Thus, the Research Institute for Post- Mining (FZN) at the TH Georg Agricola University in Bochum, Germany, has developed a holistic approach to meet these postmining challenges including further expertise present at our university. Here, the four strategic research pillars are (1) technical geoecology and hydrogeology to avoid and mitigate risks underground, (2) geomonitoring to evaluate and protect the surface, (3) industrial heritage preservation and engineering to secure and reuse brownfields such as mine sites, and (4) economic transformation planning of mining regions to enable a prosper future for generations to come. In all efforts, we aim to achieve the fundamental goals of the UN to deal with the resources of our planet responsibly and sustainably. Furthermore, we are synergizing increasingly with national and international networks in the interest of social, economic, and environmental stakeholders.

Jul 23, 2020

By M A. Harrington-Baker, J M. Trudnowski

Sulfate-reducing bacteria (SRB) have the ability to immobilise dissolved metals by precipitating them as sulfides, provided that a favourable biochemical environment is created. Such an environment includes the presence of sulfate, anaerobic conditions and the availability of organic carbon. If such conditions are engineered within a reactive barrier or field-bioreactor, most metals can be effectively removed. To demonstrate this concept, three passive SRB field-bioreactors were constructed in 1998 at an abandoned mine site in the vicinity of Butte, Montana, USA to treat acid mine drainage with characteristic elevated concentration of metals and low pH. Performance of the field-bioreactors, using aqueous samples, was monitored over 32 months until the project was terminated, field-bioreactors were decommissioned and solid matrix sampling of the reactive matter was performed. The most important analytical results are presented in this paper together with conclusions regarding the appropriateness of the field-bioreactors construction features. Only Zn, Cu, and Cd were being removed as sulfides due to SRB activities. Changes in concentrations of other metals (Fe, Mn, Al, As), which do not necessarily precipitate as sulfide, seemed to be affected by SRB only in an indirect manner by responding to increased pH caused by SRB activity. An innovative cellular containment system used for placing organic matter worked very well in preventing settling of the organic matter and ensuring uniform flow of AMD throughout the entire cross-section of the organic carbon with no preferential flow paths This demonstration was funded by the US EPA and was jointly administered by the EPA and the US DOE under DOE contract number DE-AC22-96EW96405. The project was implemented by MSE Technology Applications, Inc, Butte, Montana, USA.

Jan 1, 2003

By R. E. Dye

IF gold mining is to assume, or it might be better said to resume, a place of ' importance in the national economy of this country following the present war, then one must accept the thesis that gold will maintain the place it has for many generations held in the minds of men as a substantial and lasting emblem of material wealth-a metal in exchange for which men have always been ready to give up the possession of their worldly goods. The thought bas been advanced by some that gold is not necessary as a basis for exchange, that it has no real value anyway and, therefore, the world would wake up some morning to find that no one wanted gold and that, over night, its possession bad in some way ceased to be desired. Holding an equally extreme view there are those who advance the idea that, following the war, gold will in some mysterious way enjoy a fantastic increase in value. Neither of these extreme views can be successfully supported. To presume that by legislation or by general agreement gold would be or could be, over night, dethroned to the position of common stone is wholly beyond the realm of any possibility. The thought that this could come to pass is advanced by, and is attractive to, only those peoples who do not have gold and do r:ot have the means of producing it. To believe that the fundamental value of gold will suddenly change is likewise fantastic. I refer to the fundamental value, not the dollar price, of gold, for it cannot be denied that, with the colossal war expenditures now being made and with the huge national debts which are being piled up, there is a possibility, indeed per-haps a likelihood, that the dollar price .of gold may be revised upward. For the purpose of this discussion, however, that possibility is irrelevant and need not be considered.

Jan 1, 1943

By Geo. E. Cole

A GREAT deal of time and energy is now being devoted to the study of post-war reconstruction and rehabilitation, in spite of the fact that as yet we have not won the war in which we are presently engaged. If you feel that the study of post-war problems takes our thought away from the problem immediately before us, you may well query, "Well! What has all that to do with winning the war, our most urgent problem today?" The answer has been given by Principal James of McGill University, Chairman of the Cabinet Committee on Reconstruction: "Reconstruction is something which must be thought of in advance, partly for the purpose of recognizing exactly the influence of war-time activities, controls, and regulations on the post-war Canadian scene. Many people are acutely interested in this great problem. It is not that they are not interested in the war itself, or epochal events that are taking place from day to day. They have a vision of that future which they hope will be Canada's, and this vision inspires them to even greater efforts at the present time". The trend of events would indicate that changes, economic and industrial, after this war will be greatly out of line with those that followed previous wars in history, for the present struggle has involved every nation in the world. In the peace that will come, every engineer will have a task in bringing the most desirable order out of the most distressing chaos. We certainly are living in a changing world; we are witnessing geo-graphical and economic readjustments that no other generation in world's history has ever witnessed. And there is an opinion gaining strength in our Dominion, as in other lands, that after this war we shall live in a world in which our process of thinking and our very way of life will have to undergo drastic changes to cope with the new order of things. Sadly our world of today has had to revise the sublime vision that nation shall not lift up sword against nation, while salvage operations continue to beat ploughshares into tanks and the peaceful pruning-hook into a weapon for the deviltry of the commando.

Jan 1, 1943

By Tex M. Kubacki

In 2007, the University of Utah Seismograph Stations (UUSS) temporarily expanded its seismic monitoring network in Emery County, Utah, in response to the August 6 Crandall Canyon mine collapse that trapped six workers. In spite of this additional coverage, no seismic events were located in the area during a six-day period (gap) from August 8 to August 13. The Mine Safety and Health Administration (MSHA) ?Command Center Log Books? however, contain references to 16 instances of underground ?bumping? and ?bouncing? that occurred during the gap. When ground truth information provided by the log books is compared to the raw seismic data recorded by the UUSS network, the correlation offers insight into the chronology of mininginduced seismicity (MIS) in the aftermath of the collapse. The new research focuses on identifying and locating seismic events that occurred during the six-day gap using double-difference relocation techniques and correlating them with log book ground truth. Ten seismic events were identified in the vicinity of the mine during the six-day gap, ranging in magnitude from coda magnitude (MC) 0.5 to 1.4. Three of these events were amenable to location by double-difference techniques. The location of one of these events is directly confirmed by ground truth information from the log books. As a result of this new research, the accuracy of Crandall Canyon double-difference locations has been improved, and the number of events correlated with ground truth information has increased. The seismic events occurring in and around the collapsed area appear in two distinct sections of the mine?east and west of the center of collapse. It was originally reported that the post-collapse events occurred in episodic clusters. The first two episodes occurred to the east, followed in time by a cluster on the west, and then by a third episode on the east. With the addition of new events to the data set, this pattern is no longer as clear, although the events still occur in clusters. Only one MIS cluster was found to occur within the bounds of the minimum estimated collapse area (Pechmann et al., 2008).

Jan 1, 2012

By Richard B. Stein

Section 25 has been assembled to give the geological, mining, or metallurgical engineer an overview of some of the important downstream operations that typically follow mining activities. This subject is obviously too broad and complex to be covered in detail within this Handbook. However, the engineer will be interested to learn about the basic fundamentals, and especially how they might affect the economics of the total project from prospecting and mining through to metals recovery and marketing. In this way, it is hoped that the engineer will have a better overall appreciation for the technical and commercial prospects of a mining and metal-producing project.

Jan 1, 2008

By C. K. Leith

THE resolution presented at the Annual Meeting of the A.I.M.E., calling on Congress to provide now for postwar accumulation of mineral stock piles under Government control, expresses, I think, the nearly unanimous view of the mining industry. As a result of the trying experiences of the first World War, Mr. Baruch, in his report of Dec. 24, 1919, to the President, urged that steps be taken at once to ensure adequate supplies of raw materials for future emergency. In the twenty years that followed, the same program was vigorously urged on Congress by many individuals and agencies, public and private, including the Secretaries of War and Navy, many members of Congress, the Bureau of Mines, the Planning Committee for Mineral Policy appointed by President Roosevelt, the A.I.M.E., the Mining and Metallurgical Society, and others.

Jan 1, 1943