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By H. Meseck

Dynamic pile test methods to establish the bearing capacity of driven piles were developed in the USA more than 20 years ago. In the Federal Republic of Germany, the first dynamic pile tests were carried out at the end of the 70's. Today dynamic pile tests are successfully used to establish the integrity and bearing capacity of driven and bored piles. The Institute of Foundation Engineering and Soil Mechanics at the Technical University of Braunschweig has developed its own method of measuring and evaluation for the execution of dynamic pile tests. The principles of the dynamic pile tests, the measuring and evaluation plant as well as the experience gained with it in the examination of cast-in-place piles are presented in this contribution.

Jan 1, 2010

By Davis Myers

OVERVIEW ?A summary of population demographics data ?Potential impact of Baby-Boomer, Generation X, Millennial demographics in the mining workforce ?Planning with constrained resources Age Cohorts ?Baby Boomers: born 1946 -1965 ?Booming economy, TV, cold war, JFK, Vietnam ?Generation X: born 1965-1980 ?There was always space travel ?PC?s, Black Monday, Challenger, Desert Storm, fall of Berlin Wall ?Millennials: born 1980-2000 ?There was always the internet ?IM, Facebook, Sept 11, Columbine

Nov 1, 2011

By R. S. Handy

THE properties of the Patiño Mines and Enterprises Consolidated, Inc., a New York corporation, are near Llallagua in the department of Chayanta in the west central part of Bolivia, South America, about 80 miles southeast of Oruro and 250 miles southeast of La Paz, the largest city in Bolivia and its virtual capital. The properties are accessible by railroad from three points on the west coast-from Mollendo, Peru, across Lake Titicaca, from Arica by way of La Paz, and from Antofagasta, Chile. The latter route, although the longest, is recommended by the companies as affording a more gradual introduction to the high altitudes; the mine being 13,000 ft. above sea level. The company operates its own railroad from its properties at Uncia to Machacamarca on the Chile & Bolivia R. R., a distance of 60 miles. This railroad is well equipped and well operated, and its location among the mountains surrounding Uncia represents excellent engineering skill. In fact all of the railroads, although they are of only a meter gage, are remarkable for the excellence of their construction, the arrangement of their dining and sleeping cars and the precision of their operation. There is only one drawback to rail- road and hotel accommodations and that is the absence of heating facilities, which does not seem to affect the natives but keeps a tenderfoot's teeth chattering continually. The company is a consolidation of the Patiño company, owning properties at Uncia, with the Compafiia Estanfera de Llallagua, a' Chilean corporation owning contiguous properties at Llallagua. Before the consolidation these companies were deadly enemies, and there still remain at the surface plant at Uncia the fortifications and underground defences provided during the warfare between the two factions. Also, in the Azul, or "Blue" tunnel at the junction line between the two properties is a strong steel barricade still bearing marks of the bullets fired during the various armed tilts between the workmen of the two companies. The headquarters for the mining operations and the milling plant have been moved since the consolidation from the original location at Uncia to the Llallagua side of the mountain, where the Chilean company's operations were carried on. The historic old town of Uncia, with its massive stone buildings of Spanish design, is a wreck, while the Llallagua side is being rapidly built up with modern structures.

Jan 1, 1929

By W. D. Ryan

The American public has at all times been prone to discuss important questions that call for consideration and adjustment. Debatable subjects upon which sides may be taken always receive unusual prominence, but other questions equally important may be neglected. The real "paramount issue," calling for remedial action, is the ever-increasing number of deaths caused by preventable accidents. This matter demands the attention of the entire American people; the importance of accident prevention can not be overemphasized, and in many phases of American life, especially among the mining and allied industries, far too little real attention has been given the importance of conserving life and limb by accident prevention. ACCIDENTS COMPARED TO WAR AS A CAUSE OF DEATH Harry T. Hoffman, Wyoming labor commissioner, writes the following: It is one of the peculiar complexes of this rapidly moving age that we all stand aghast at the horrors of war and view with appar- ent indifference the greater havoc of industrial peace. Did you ever stop to think that approximately twice as many people were killed by accidents in the United States in 1929, as there were American soldiers killed in the entire period of the World War? Every employer and every worker should be thoroughly aroused over the tremendous toll levied against industrial forces by accidents which are largely preventable and develop a faith in safety efforts that will fire them with a zeal as pronounced as that of their religion or their patriotism. Let us remember safety-first to the end that the workman shall live to enjoy the fruits of his labor; that his mother shall have the comfort of his arm in her age; that his wife shall not be untimely a widow; that his children shall have a father; that crip- ples and helpless wrecks who were strong men shall no longer be a by-product of industry.

Apr 1, 1931

By Fábio de São José

Sistemas de moagem são projetados baseando-se, entre outros parâmetros, no consumo de energia das rotas existentes. Consideram-se custos com energia um desafio para a indústria mineral, pois a maioria da energia disponível ao processo é inevitavelmente absorvida pelos equipamentos e somente uma menor porção é destinada à fragmentação desejada. Hoje, a maioria das teorias utilizadas na avaliação do desempenho energético parte dos estudos de pesquisadores como Fred Chester Bond. De acordo com Bond, Work Index (WI) é um parâmetro representativo da resistência à moagem do minério, servindo para medir o consumo de energia na fragmentação e para comparar o comportamento de diferentes minérios. Estudos recentes comprovam que o WI de materiais em mistura pode ser medido, geralmente, com alto desvio devido às diferenças existentes de moabilidade de cada tipologia. Este trabalho consistiu na determinação do WI de minério de zinco silicatado com elevações nos teores de esfalerita (ZnS) e galena (PbS), devido à avanços na lavra, minério composto unicamente por willemita e suas misturas. Valores encontrados mostraram que a presença significativa de minerais de classes distintas daquele predominante na frente de lavra pode influenciar na determinação de parâmetros importantes para o processamento mineral. Amostras foram fornecidas pela Votorantim Metais Zinco.

Aug 8, 2018

By Dany Pelletier, Yeves Breau, Ahmed Bouajila, Claude Gagnon

"In flotation circuits, direct measurement of the volumetric flow rate delivered by electromagnetic flowmeters is often difficult to obtain particularly due to piping and flow constraints. However, on-line material balance calculation could offer a reliable alternative to flow rate sensing. This paper describes an on-line material balance software package as applied to a copper flotation circuit for mass flow rate estimation mainly based on the output of an x-ray fluorescence onstream analyser. Rule-based procedures for the management of the main calculation modules are designed and integrated to a Comdale expert system. Attempts to diagnose the flotation process from mass flow rate data are also discussed.INTRODUCTIONThe need for improved process diagnosis, control and optimisation has become more evident for the mineral processing industry in the last decade. Therefore, new process variables need to be inferred or measured particularly in highly multivariable processes such as flotation. This process is subject to a wide variety of disturbances mainly generated by frequent and sometimes abrupt changes in physical and chemical characteristics of the ore and due to some irregularities in manual process operating procedures.A flotation circuit scheme is always a complex network counting more than two dozens of slurry streams. Information about those streams (%solids, metal content analysis, and flow rates) are important for process diagnosis, performance evaluation control and optimization (1,3).On-line sensing instruments such as x-ray fluorescence (XRF) on-stream analysers (OSA), gamma density gauges and electromagnetic flowmeters have been developed for the measurement of those variables. Unlike the other variables, stream flow rates could be determined by different ways:"

Jan 1, 2000

By Frank B. Fulkerson

Aluminum production in the Pacific Northwest has a new potential for expansion and increased stability of operation. This new potential results from greater availability of power; lower freight rates on alumina and aluminum; good market prospects for the metal, including western aluminum market expansion following a decline in defense requirements in the 1950's; and possibility of developing bauxite deposits in the Pacific Basin as well as other mineral resources. INTRODUCTION This is a report of a special study by the Bureau of Mines of the primary aluminum industry of the Pacific Northwest. It outlines developments relative to the United States as a whole.

Jan 1, 1962

By John R. Craynon

Science and Sustainable Development Each of the ?pillars? of sustainable development are directly impacted by mining. We need science to understand exactly how mining contributes to each. Overview of presentation ? History of mining and sustainable development ? Role of stakeholders in measuring/accepting contributions of mining to SD ? Identified ?shortfalls? in understanding mining and SD ? Science needs

Aug 1, 2013

By J. Hart, P. W. Conrad, S. Rosenthal, R. A. Hogan

The Mining Engineering Department at Montana Technological University (Montana Tech) has a new Mine Safety and Health Administration (MSHA) approved program for Part 46 and Part 48 mine health and safety training. The training program will utilize the facilities and faculty from Montana Tech’s Mining Engineering and Safety, Health, and Industrial Hygiene departments to provide superior mine health and safety training to the mining industry. The faculty of each department includes professionals with experience in safety training and the mining industry. The training program incorporates adult learning techniques and extensive hands-on activities in all training modules. The instruction will exceed MSHA requirements. The resources available on Montana Tech’s campus will be utilized to strengthen the training program providing the mining industry with a world class mine health and safety training program.

Feb 1, 2023

By Filippo Leoni, Wesley Schmutzler

"The LPV-111 East Back Levee Improvement Project lies along the Gulf Intracoastal Waterway (GIWW) in Orleans Parish of New Orleans, La., and is an essential component of the New Orleans Hurricane Protection System. The Hurricane Protection Office of the U.S. Army Corps of Engineers (USACE) attributed failure of the New Orleans East levees system to overtopping, erosion and subsequent breaching of LPV-111 along the GIWW, as well as other sections of flood protection during Hurricane Katrina in 2005. The existing levee suffered extensive damages from Hurricane Katrina, such that the USACE elected to provide earth stabilization and to rebuild the levee sections. Due to the adverse geotechnical properties of the foundation soils, the Corps deemed ground improvement necessary to stabilize the new levee and to limit its footprint. Wet Deep Mixing Method (DMM) was selected as the most suitable technology for this task.ChallengesDesign: This reach specifically protects East New Orleans and the Bayou Savage National Wildlife Refuge, the largest urban wildlife refuge in the U.S. and home to several threatened or endangered species of birds as well as many reptiles, amphibians and small mammals. The Corps chose DMM due to the sensitivity of the protected marshlands and because the method limits the footprint of the raised levees. The increase in the load bearing capacity of the treated soil significantly decreases the footprint necessary to attain the required height increase. This limitation required the new levee to have steep slopes, drastically increasing the surcharge on foundation soils characterized by overall poor geotechnical properties (soft clays and peats). The design also considered the increased horizontal stresses on the levees due to the extreme storm surges during a hurricane.The design of the 1.6 m diameter (5.25 ft) DMM elements called for overlapping them to form a double auger element that formed buttresses perpendicular to the levee alignment. The contractor installed the buttresses at a maximum on center spacing of 4.7 m (15.5 ft). One additional double auger DMM element was midway between consecutive buttresses at the centerline of the levee to further help prevent settlement (Figure 1)."

Jan 1, 2013

By Basil B. Zavoico

The World War I1 spread to Russia on June 22, 1941, when the German Armies began their invasion. The Soviet industries, which were already engaged in a tremendous armament program, further accelerated the flow of munitions, and equipment and supplies for all purposes not directly military were either entirely eliminated or reduced to an absolute minimum. With the occupation by German armies of the Dniepr and Kharkov industrial regions, this trend was necessarily further accentuated. The oil industry of Russia, in consequence, was left to rely more and more upon itself, its own very limited manufacturing facilities, extensive repair shops and probably much used equipment out of order stacked in the warehouses. All evidence available to date points to the fact that the new situation not only did not affect the production either quantitatively or qualitatively, but, on the contrary, caused a larger flow of much needed fuels to the country's war machine, primarily by renaissance of both management and labor. The oil industry of the Soviet Union, left to depend entirely upon itself for equip ment and supplies, and even for new workers and technicians to replace those called into the services, did and is still doing a good and effective job. Since it could not hope for new equipment and parts and could not blame any other industry for the delays in delivery, it dragged out old machines from storage and repaired them in its own machine shops. Often such stored and used equipment was but slightly defective, waiting for some small part from factories in Central Russia, plants that now were either in German hands or entirely converted to the manufacture of munitions. More particularly, instead of the pipe that could not be taken to the Caucasus from Central Russia, casing reclaimed from abandoned or submarginal wells was used, or pipe from the abandoned or but slightly used pipe lines; and this practice is being continued even now on a large scale, to create an ample reserve for the duration of the conflict. Indirectly such a development was even an improvement on pre-war days, when many wells about to be completed had to wait for weeks, even months, for the arrival of new pipe, all blame then being placed outside of the industry on the factories in Central Russia. For the purpose of reclaiming equipment and pipe still usable, special crews were organized. The war also caused much quicker adaptation of certain American practices and introduction of many emergency measures, such as: removal of derricks upon completion of wells and the use of drilling equipment mounted on skids for rapid transfer from location to location—both of these practices, while standard in the U.S.A., being new in Russia; installation of simplified surface pumping units; substitution of wooden bearings in the surface pump equipment; completion of wells in the Ural-Volga district, where formations are hard and tight throughout the sedimentary column, without either casing or

Jan 1, 1942

By Basil B. Zavoico

The World War I1 spread to Russia on June 22, 1941, when the German Armies began their invasion. The Soviet industries, which were already engaged in a tremendous armament program, further accelerated the flow of munitions, and equipment and supplies for all purposes not directly military were either entirely eliminated or reduced to an absolute minimum. With the occupation by German armies of the Dniepr and Kharkov industrial regions, this trend was necessarily further accentuated. The oil industry of Russia, in consequence, was left to rely more and more upon itself, its own very limited manufacturing facilities, extensive repair shops and probably much used equipment out of order stacked in the warehouses. All evidence available to date points to the fact that the new situation not only did not affect the production either quantitatively or qualitatively, but, on the contrary, caused a larger flow of much needed fuels to the country's war machine, primarily by renaissance of both management and labor. The oil industry of the Soviet Union, left to depend entirely upon itself for equip ment and supplies, and even for new workers and technicians to replace those called into the services, did and is still doing a good and effective job. Since it could not hope for new equipment and parts and could not blame any other industry for the delays in delivery, it dragged out old machines from storage and repaired them in its own machine shops. Often such stored and used equipment was but slightly defective, waiting for some small part from factories in Central Russia, plants that now were either in German hands or entirely converted to the manufacture of munitions. More particularly, instead of the pipe that could not be taken to the Caucasus from Central Russia, casing reclaimed from abandoned or submarginal wells was used, or pipe from the abandoned or but slightly used pipe lines; and this practice is being continued even now on a large scale, to create an ample reserve for the duration of the conflict. Indirectly such a development was even an improvement on pre-war days, when many wells about to be completed had to wait for weeks, even months, for the arrival of new pipe, all blame then being placed outside of the industry on the factories in Central Russia. For the purpose of reclaiming equipment and pipe still usable, special crews were organized. The war also caused much quicker adaptation of certain American practices and introduction of many emergency measures, such as: removal of derricks upon completion of wells and the use of drilling equipment mounted on skids for rapid transfer from location to location—both of these practices, while standard in the U.S.A., being new in Russia; installation of simplified surface pumping units; substitution of wooden bearings in the surface pump equipment; completion of wells in the Ural-Volga district, where formations are hard and tight throughout the sedimentary column, without either casing or

Jan 1, 1942

By James L. Coburn

Leaching is defined as a form of extraction in which a valuable constituent is removed from a solid body by mass transfer to a solution which, for the purpose of this discussion, is considered to be an aqueous medium. Historically, leaching has been applied to the recovery and purification of many elements. This paper, however, is directed toward the recovery of copper, uranium, vanadium, and precious metals included in the following systems: 1. The leaching of copper minerals, sulfides and oxides, by acid or by ammoniacal leach solutions with or without an oxidant. 2. The leaching of gold and silver, either native metals or as minerals by an oxygen-containing alkaline cyanide solution. 3. The solubilization of certain uranium and vanadium minerals by oxygen or oxidant-bearing lixiviants. Many other systems of this general type exist, but from a production standpoint, these three systems account for most of the major values recovered by leaching.

Jan 1, 1975

By John J. Sammarco

The U.S. Bureau of Mines has developed a regulated, intrinsically safe, rechargeable power supply for portable electronic equipment for underground use. The regulated output is ideal for microprocessor power requirements and is suited for operation in hazardous environments. Two rechargeable, sealed batteries are contained within the power supply. Provisions are made to use an external source of power if these batteries fail. Provisions are also made to charge these internal batteries when needed. The circuit is composed of three main circuits: the main regulator circuit, the input protection circuit, and the output protection circuit. The main regulator circuit provides remote voltage sensing, current sensing, fault monitoring, and internal thermal protection. The input protection circuit checks for excessive input current and low battery conditions. The output protection circuit contains two overvoltage detection devices. Schematics, a parts list, and a calibration procedure are provided in this report to enable readers to fabricate the power supply.

Jan 1, 1989

By Werner Wenzel

Whisker growth during the reduction of iron ores The phenomenon of whisker growth can be observed in a number of solid-state crystallisation reactions, which, apparently, appear in6 the first instance as though they are two independent processes. From such reactions, one can find the whisker type of crystallisation on solid bodies. These examples show, that the whisker growth is neither due to certain crystal forms with predetermined temperature and pressureranges, nor to parameters, which, ad hoc, are necessary for the crystallisation. In all cases the whisker formation seems to depend on nucleation and the availability of crystallizing material in direct environment of such a nucleus, under given parameters of a system. One can generally state, that the research of whisker growth with the aim of establishing proper physical laws, to determine the foundamentals of whisker formation and whisker growth, is at present under active study. We can conclude that, although a great number of hypothesis have been proposed; no concluding theory has yet been arrived at. In the institute for ferrous metallurgy of the technical university of Aachen, research works are undertaken to find an explination to various metallurgical phenomena through help of whisker growth which was observed under varying conditions of iron ore reduction. This was possible by using refined microscopic techniques through which the whisker growth on solid oxyde substrates is detected. This refined technique combines the latest methods of surface examination with the help of stereo-scan-electron-microscope and proper and carefull preparation of surface to be stereo-scanned.

Jan 1, 1971

By D Gerrard, J Begelhole, J Gerber

The Iron Magnet deposit has been mined since 2007 when Arrium (then OneSteel) commissioned the magnetite concentrator to supply feed to the pelletising plant in Whyalla. The concentrate quality requirement for the customer required consistent product with minimal variability. In the early stages of operation, it was identified that the feed variability introduced significant changes in the concentrate quality, which was outside the acceptable customer limits.In 2011, a geometallurgical regression model was developed that allowed for the estimation of concentrate quality produced from the feed material. This was based on a laboratory-scale Davis Tube Recovery (DTR) test performed on the feed material. The objective of the project was to characterise the raw ore in the pit to allow for blending prior to crushing. By blending the feed to the concentrator, minimal concentrate quality variation within the plant was achieved. The orebody was divided into geometallurgical classes, called ore types, based on the mineral texture and magnetic mass recovery. Each geometallurgical class consisted of material with similar metallurgical performances. For each individual blast pattern, the ore was grouped into the geometallurgical classes and a composite sample was created. The composite sample was put through the laboratory-scale DTR test and the results were used to estimate the metallurgical performance of the material.The characterisation process and feed pile build methodology was applied in early 2013 and went through an optimisation and streamlining phase. Since the implementation of the geometallurgical characterisation process, the plant has seen a significant reduction in concentrate variability and measurable throughput gains. The characterisation process has also increased the amount of material that is now classified as ore.CITATION:Gerber, J, Gerrard, D and Begelhole, J, 2015. Geometallurgy of the South Middleback Ranges magnetite deposit – predicting plant performance from the pit, in Proceedings Iron Ore 2015, pp 555–560 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Pablo Hadzeriga

There are two places in the world where potash, trade name for potassium chloride, is economically recovered from naturally occuring brines by solar evaporation. One is at the Dead Sea and the other at Wendover, Utah. American Potash and Chemical at Trona, California recovers potash from natural brines, but uses fuel to accomplish evaporation. Under proper meteorological conditions the use of solar evaporation might be desirable from the economical standpoint. Of course, this may not be true when, if by artificial evaporation, a group of very valuable salts are recovered. This is the case of the American Potash operation at Trona. Solar evaporation has its limits. The working temperature is low. We may say, just to cover most areas of the world where solar evaporation may be practical, that it will take place between 18°C and perhaps around 45°C. In most cases the average working temperature expected will be around 25°C.

Jan 1, 1963

By L. E. Porter

The demand for crude oil on the Pacific Coast during the year 1945. was so acute that the California crude supply had to be augmented by tank-car imports from the Texas and Rocky Mountain fields. Crude imports reached a high of 64,800 bbl. per day during June, with a total of 14,259,000 bbl. imported during the first 11 .months. The U. S. Navy also implemented the crude output from California pools by drilling and completing approximately 300 wells in the Naval Petroleum Reserve No. 1 (Elk Hills), from which an established production of 65,000. bbl. per day was reached in late February and maintained until Aug. 17, 1945, when it was reduced to its preprogram level of 15,000 bbl. per day. Even with the conclusion of the Pacific war on V-J day (Aug. 14), the military petroleum product requirements have permitted little material reduction in output of California crude to prewar rates. During the year, a total of 327-760,000 bbl. of crude was produced, or 19 per cent of the total crude production within the United States during the same period, as compared with 310,996,000 bbl. or 18.4 per cent of the nation's crude production in 1944.

Jan 1, 1946

By L. Allan White

Instrumental analysis is an indispensable tool to many phases of research on rare-earth metals and their compounds; therefore, the development of new and improved instrumental techniques is essential. This report describes an emission spectrometric analytical method using direct-current carbon-arc excitation of various rare-earth-oxide mixtures. Lanthanum oxide serves the dual purpose of an internal standard and a constant major constituent. The versatility of the method was demonstrated by three different applications: (a) Analysis of complex rare-earth concentrates; (b) determination of impurities in high-purity rare-earth oxides; and (c) detection of rare-earth elements in other types of matrices, such as those resulting from beneficiation of rare-earth ores. The average error of analysis in the concentration range of 0.2 to 10.0 percent was 14.6 percent for a group of complex synthetic mixtures of rare-earth oxides. An average error of analysis in the concentration range of 0.05 to 0.50 percent was 21 percent for a group of high-purity rare-earth oxides.

Jan 1, 1959

By Michael Gauna

An evaluation and analysis of a coal pillar bump in a West Virginia mine indicated that the pillar bump occurred because of the unique combination of controlling factors. The pillar?s development stability factor of 2.6, based on Mark-Bieniawski strength and tributary loading, would typically indicate an adequate pillar size for long-term main entries. A combination of multiple-seam mining geometry and geological conditions resulted in stress concentration leading to the coal pillar bump. No high extraction mining had been performed in the area and the overlying works appeared to have adequate stability factors. However, it was interpreted that long-term flooding had softened the overlying pillar system and rendered all but the largest pillars ineffective. Contributing factors include large overlying pillars transmitting stress through the approximately 60 ft of interburden and the failed pillar?s location at a transition in the immediate roof from shale to hard, massive sandstone. Other contributing factors include sandstone channeling forcing the development section to mine the pillar smaller than surrounding pillars in an attempt to avoid the channel, the relatively high overburden of 1,100 ft, and the pillar?s position in the bottom of a trough within the coal horizon. Pillars subjected to similar conditions on the other side of the section did not fail where the roof was composed of shale, even though the roof exhibited evidence of high stress concentration. An analysis was undertaken to determine appropriate pillar size for future mining. The conditions were evaluated by investigating mine historical conditions, assessing pillar bearing pressures, and using Lamodel 2D coupled with traditional Mark-Bieniawski pillar strength and tributary area loading stability factors to determine the stress levels for the pillar. Recommendations for future pillar sizes were based on the critical load bearing capacity identified by the analysis. To date, no further pillar bumps have occurred.

Jan 1, 2008