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By W. P. Huleatt, R. B. McCulloch

"The Big Four zinc-deposit, directly above the north bank of the Green Mountain Reservoir on the Blue River, Summit County, Cole., was discovered in 1937 by the present owner, Walter McDaniel, who lives on the property. Mr. McDaniel, together with members of his family, have worked the mine on a small scale since its beginning and have shipped quantities of sorted high-grade ore to the International Smelting Co. at Tooele, Utah, and the Combined Metals Corp. at Bauer, Utah. More recently, parts of the nine have been operated by lessees.The property had been examined previously by the Federal Geological Survey, and the geological report was made available' to the Bureau of Mines.The Big Four mining claim was located in 1937 by Walter McDaniel and his wife Frances,- who had been prospecting in the vicinity since 1933. The discovery of the high-grade zinc deposit caused considerable excitement, as it had not been regarded as a mineralized area.Mining was begun in 1937 and carried on until 1944 by Mr. and Mrs. McDaniel with the help of a few hired miners. During 1944, parts of the mine were leased: to various parties Who produced small quantities of ore but did no development work.Shipments during 1941 .totaled 752 tons; during 1942, 387 tons; and during 1943, 510 tons. From the beginning of 1944 to April of that year, 98 tons wore produced and shipped to Utah,Since the lessees began operations, a grade of 30 to 35 percent zinc has been maintained by careful sorting. No production has been recorded for 1945.The Big Four mine is situated on Colorado State- Highway 9 between Dillon and Kremmling on the south face of Green Mountain overlooking the Green Mountain Reservoir, a Federal irrigation project on the Hue River, Green Mountain rises 1,600 feet above the general level of the valley to an altitude of 9,408 feet and the surrounding terrain, i s correspondingly mountainous and rugged."

Apr 1, 1946

By Fred N. Kissell, Natesa I. Jayaraman

Introduction This paper describes a recent Bureau of Mines research project that resulted in a simple procedure for reducing the dust exposure of longwall shearer operators. This project involved the development and testing of a water spray and passive shield system to hold dust against the face and away from the shearer operators. This system is known as the Shearer- Clearer.

Jan 1, 1981

By G. W. Birge

As a part of its overall program of coal carbonization, the Bureau of Mines is studying the coking properties of coals that may be used for metallurgical purposes. The objectives of this study were given in detail in a previous report.2/ The inherent suitability of coal for metallurgical use depends primarily on (1) chemical composition, (2) preparation characteristics, and (3) carbonization behavior. The first two factors, as well as the available reserves, are considered in selecting coals for carbonization tests. The selection of coal beds in Westmoreland County for coking tests was based, in part, on estimates of the coal reserves by Dowd,3/ who estimated the recoverable reserves in beds 28 inches or more thick, in thousands of tons, as follows: [ ]

Jan 1, 1957

By L. M. Pidgeon, K. T. Aust

There has been considerable interest in the possible use of titanium in magnesium alloys.' Zirconium has shown some promise in this connection2 and its general similarity with titanium suggests that the latter might act in a similar manner. A literature survey revealed that quantitative data on the Mg-Ti system was unavailable. Several patents3 have claimed that titanium additions from 0.2 to 4 pct to magnesium alloys were possible, but no mention was made as to the form in which the titanium existed in the alloy. Kro114 succeeded in introducing only traces of titanium into magnesium by bubbling TiCl4 through the metal under argon or by reacting it with sodium titanium fluoride. The application of theoretical data given by Carapella5 based on Hume-Rothery's principles, involving atomic size factor, crystal structure, valency and the electro-chemical factor, suggests that a Mg-Ti alloy is a favorable case, and the system appeared to warrant experimental examination. Experimental Procedure and Results THERMAL ANALYSIS If titanium is appreciably soluble in magnesium, a change in the melting point of the magnesium might be detectable using standard cooling curve methods. Magnesium was melted in graphite crucibles under an argon atmosphere, the assembly being enclosed in a silica tube. Graphite thermocouple protection tubes served also to stir the melts. The apparatus was very similar to Fig 1, with the addition of a refractory and baffle system to prevent undue heat losses from the top of the crucible. Chromel-alumel thermocouples were calibrated using Al of 99.97 pct purity. Dominion Magnesium Limited sup- plied redistilled high purity magnesium of the analysis given above. Titanium was added in three different forms: 1. Titanium powder —100 mesh, from the Titanium Alloy Manufacturing Co., Niagara Falls, N. Y. 2. Sheet titanium from the U.S. Bureau of Mines, produced by Mg reduction of TiCl4. 3. Magnesium —50 pct titanium master alloy from Metal Hydrides Inc., Beverly, Mass. The melting point of the high purity magnesium used was measured experimentally as 651.0°C. More than a dozen tests were conducted using titanium from the three sources referred to above, in calculated additions up to 20 pct titanium, at temperatures between the melting point and 1000°C and holding periods up to 6 hr. In no case was evidence obtained of solubility of titanium in magnesium, using inverse-rate and time-temperature curves. The melting point of the magnesium was unchanged within the accuracy of measurement, namely -+0.5°C; and no other thermal arrests were detected. Metallographic investigation of the thermal analysis billets indicated that the titanium additions were apparently mechanically entrapped in the magnesium in segregated areas. Consequently, these samples were not analyzed for titanium. The master alloy proved to be a mechanical mixture of titanium particles in a magne- sium matrix. These results indicated that the titanium solubility, if such existed, could not be obtained by the usual thermal methods. X RAY DIFFRACTION INVESTIGATION In an effort to detect solubility of titanium in magnesium, samples were investigated using both the Debye-Scherrer and the Focusing Back-Reflection methods. Filings from samples of the thermal analysis billets and from pure magnesium were annealed in argon one hour at 350°C to relieve mechanical strain. Measurements made of the interplanar spacings showed no difference between the Mg-Ti samples and pure magnesium. The interplanar spacings could be measured to within 0.0002A, and the greatest variation found was 0.0004A, in the back-reflection method. The diffraction lines for magnesium were not shifted by the titanium additions indicating that the solid solubility of titanium in magnesium is of a very low order—less than 0.5 pct. From both diffraction methods, a d or interplanar spacing of 0.817A was obtained for the redistilled high purity magnesium. This latter value is not given in the standard X ray diffraction cards for magnesium metal or vacuum distilled magnesium. Theoretical calculations for a close-packed hexagonal space lattice for magnesium indicate that the planes {2134) should give a line which was found. The relative intensity for this reflection at 0.817A is slightly less than that at 0.870k for magnesium. SOLUBILITY OF TITANIUM IN LIQUID MAGNESIUM The Mg-Mn system was examined by Grogan and Haughton6 who were

Jan 1, 1950

By Thierno FALL

This paper describes the study of the work-roll during the hot rolling process thanks to a 3D model built with the Finite Element Method (FEM). In terms of computational cost, that method needs high resources compared to 1D model which are mostly used. However, the 3D model is built to have a better understanding of the work-roll thermal and mechanical behavior during the hot rolling process. The thermal model shows that the highest temperature reached during rolling are within the range of 500°C and 600°C. The thermal field input used to simulate the mechanical behavior of the work-roll shows a biaxial thermal stress state, in the circumferential and axial planes. However, a peak of radial stress is observed in the backup zone. It did not generate plastic strain but could influence the fatigue behavior of the work-roll.

Oct 1, 2019

By Raymond O. Dannenberg

The Bureau of Mines conducted laboratory and full-scale tests to develop a process for improving the flotation characteristics of lime-treated waste water produced by the Kennecott Copper Corp., Magna, UT. Unknown substances in the waste water reduced the flotation efficiency of the metal sulfides. An estimated annual loss of 795,000 lb Cu, 232,000 lb Mo, 5,625 tr oz Ag, and 617 tr oz Au would result from recycling the total flow from the lime treatment plant to the flotation mill in an effort to conserve water and reduce associated expense. The tests indicated that aeration or treatment with activated carbon significantly improved the water quality. The improvements in molybdenum recovery averaged 8 pct for carbon, 11 pet for activated carbon, and 16 pct for combined aeration and activated carbon. The combination of the two processes produced water quality as good as or better than normal feed water.

Jan 1, 2011

By Xiao Huang, Jean-Francois Thibault, Ali Merati, Prakash C. Patnaik

Single-crystal nickel-based superalloys are the current state-of-the-art technology for the manufacture of turbine blades. This technological improvement of the turbine blade has brought a considerable increase in its cost. Repair and overhaul of service stressed single crystal turbine components is an economic necessity for life cycle cost reduction of engines since the cost associated with replacement is significantly higher than its counterpart polycrystalline component. This paper will first review the recently reported research in developing repair technologies used for DS and SX components. These techniques repair the crack or defect while at the same time ensuring that the mechanical properties do not deteriorate and, more importantly, that the single-crystal microstructure is not jeopardized. It will then be followed by a brief overview of the research conducted and initiated by the authors with regards to the repair of single crystal alloys.

Jan 1, 2004

By Alexandre Schultz Rizek

Esse projeto visou a substituição do sistema de controle instalado por um padrão RUSSULA, sistema esse que controla um laminador de barras e de rolos de 500.000 toneladas/ano na Usina Presidente Vargas da CSN em Volta Redonda, RJ/Brasil. Juntamente com o sistema de controle, RUSSULA forneceu um novo posto de operação para a cabine central, com novas telas de operação, sendo um posto “touch”. Equipado com controladores Siemens S7-400, IHM Wonderware InTouch, acionamentos ABB ACS800 e DCS800, o sistema se apresentava ineficaz, exigindo a otimização do processo, aumento de produtividade, diminuição de paradas, diminuição de perdas metálicas e maior confiabilidade no controle, o último através das ferramentas RUSSULA implementadas no software, como por exemplo detecção automática de sucata, controle de tração, controle de laço, rastreamento do material no laminador, otimização de corte das tesouras e barra fantasma.

Aug 17, 2017

By Bern Klein, Randy Blaskovich, Reem Roufail

"Morphology is a tool that is rarely used for mineral breakage mechanism evaluation. Ground particles are typically assessed for their size distribution. They are also visually analyzed using image analysis. However, image analysis is not a comprehensive evaluation of the particle surface texture. It evaluates particle’s size parameters such as area, diameter, and perimeter amongst other features. On the other hand, morphology analysis takes the particle assessment to another level of detail. Morphology analysis evaluates particles’ roundness, elongation and angularity that would indicate the degree of roughness of the particle. According to Roufail and Klein (2009), rougher surfaces are generated due to breakage along grain boundaries – intergranular breakage. Mill operation, particularly mill speed, dictates the dynamics in the mill. Stirred mills are known to break the particles via abrasion under standard operation. However, if the dynamics of the grinding media in the mill are changed, the particles could be more exposed to impact and compression loading that would lead to a different mode of breakage.In this paper, the effect of material properties and mill operating conditions on particle morphology will be studied. Hard non-sulfide versus soft sulfide minerals are compared, namely quartz and galena, respectively. Extreme mill speeds are tested covering the range of 1000 to 2000 rpm for a 4-litre Netzsch (ISA) mill. In addition to particle size distribution, micro-analysis is executed in the form of morphological analysis using a tested manual roughness point counting technique.INTRODUCTIONGrinding in general and stirred milling in particular are processes that are used to break particles to liberate metal-bearing minerals for further separation downstream. The energy required to achieve the target particle size versus maximum possible liberation has been studied intensively and it is usually the breaking point for the grinding system chosen in a process flowsheet. Operating conditions are dictated by the energy consumption. Becker et al. (2001) related different forms of energy such as input, specific, volume/mass specific energies to stress intensities and final product fineness. Other research studies focused on energy input in a stirred mill (Zheng, Harris and Somasundaran, 1996)."

Jan 1, 2011

By W. G. Sandell, L. C. Bauerle, K. C. Dean

"INTRODUCTION As a part of the wartime activities of the Bureau of Mines, metallurgical services were extended to other Government agncies engaged in purchasing and stock-piling some of the more critical and strategic materials. At the request of Dr. Alan M. Bateman, special representative of the Metals Reserve Company, metallurgical studies were made on three samples of oxide tin ore from, the States of Zacatecas and Guanajuato, Mexico. The samples were submitted for testing by A. Porraz of the Financiera Miners, S. A., institution Financiera, Edificio Guardiola, Despachos 500-507, Mexico, D. F.The samples as received were marked Nos. 1, 2, and 3 and described as follows:Sample 1. - Origin: Mining camp ""El Naranjo,"" municipality of Sombrerete, State of Zacatecas, Mexico. This sample was partly concentrated by washing and as received was all minus 10-mesh in size.Sample 2. - Origin: Deposits in Sierra. Fria and Juan Cherey, municipality, of Jerez,State of Zacatecas, Mexico. This sample represented run of-mine ore.Sample 3. - Origin: Mine ""La Frontere, "" Ranch of San Pedro del loya, State of Guanajuato, Mexico. This run-of-mine sample was low in tin content but came from a highly mineralized tin field."

Jun 1, 1947

By M I. Roberts

As Australia’s mining industry painfully retrenches, mining executives and managers strive to remain viable by seeking significant productivity increases directly through process improvement and indirectly by improving leadership and workplace culture, the most powerful determinant of productivity. Culture is the combination of people’s attitudes and behaviour, together with leadership values and focus.Comprehensive new and automated data collection and management systems promise much for improving productivity, yet despite rapid advances in measurement and sharing of data, the use of data can reduce productivity unless behavioural aspects are considered and designed as part of implementation. This is because systems drive behaviour that in turn shapes attitudes to determine culture.Experience from many mine sites and other industries in three countries confirm that the most powerful drivers of people’s behaviour are the Measurement-Analysis-Reporting system and business leadership.This paper discusses fundamentals of practical, statistically valid process measurement, analysis and reporting systems before discussing associated leadership considerations for sustained improvement in safety, productivity, employee retention, leadership, accountability and commercial returns.The key to productivity improvement is improving core processes and important support processes. In turn, the key to process improvement is identifying the major process components and their interaction by measuring and then analysing their variation and level of performance. Understanding variation is often neglected yet is usually highly significant. It is essential that the fundamentals of statistically valid yet practical process and data analysis are understood and incorporated into system design to ensure productive, informed behaviour.The design and use of Measurement-Analysis-Reporting systems influences behaviour most profoundly and determines people’s effectiveness. Behavioural aspects are detailed by focusing on six primary drivers of human behaviour and five basic systems for managing businesses. These are integrated in a seven-step process and productivity improvement methodology that combines statistical, analytical, systems and behavioural factors.The paper includes development, implementation and tracking of a project plan for improving management and leadership systems to drive aligned behaviours. This key leadership responsibility is essential for improving performance to get the most from capital while providing people with the opportunity to develop greater autonomy, which is essential for self-discipline, responsibility, initiative and accountability.CITATION:Roberts, M I, 2015. Integrating measurement, systems and leadership to build safe, productive cultures, in Proceedings Third International Future Mining Conference, pp 73–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Baisheng Nie, Longlong Yang, Tao Yang, Wenjie Jia

"Gas adsorption in coal is an exothermic and physical process. Temperature might change during the dynamical process. In order to get the temperature variation of gas adsorption process, the experiment system which can test the temperature variation and analyze the thermal effect was established. Gas adsorption experiments under different conditions were done by using the test system. The results show that temperature increases during the adsorption process. It is an exothermic reaction process. Also, the temperature variation and the variation gradient increase with the increasing of equilibrium pressure. The temperature variation value is smaller if the experiment temperature is higher. The paper will provide basic experimental data for explaining gas adsorption mechanism better.INTRODUCTIONChina is the largest coal producer in the world while it also has the most serious coal mine disasters. According to the statistics, there are nearly a thousand coal mines in China including more than 110 the key state-owned mines risking to happen coal and gas outburst. Hundreds of coal and gas outburst occur each year which often causes serious casualties and economic losses (State Administration of Work Safety, 2007). With the continuing exploitation of the coal resources, the depth of the Chinese coal mines increases about 100 meters every year which causes the situation of gas accident becoming more and more serious (Xie et al., 2006).At present, the real mechanism of gas adsorption, desorption and the diffusion process in coal and the influence factor of it are not so clear. And because of the limit of prediction method and the technological level caused gas accident prevention theory and technology not so valid."

Jan 1, 2015

By H. Wu, V. Izaxon

Intensive ventilation is required during the excavation of a mine opening and the subsequent exploitation of the mineral resources. The exchange of heat between the ventilation air and the rock mass has a major influence on the thermal regime of a mine, especially in the initial segment of the airway. In frozen ground, heat flow into the rock mass from the ventilation air can result in the eventual thawing of the permafrost, which can result in roof-rock instability. This paper presents a mathematical analysis of the dispersion process of ventilation-induced heat by thermosyphons placed on the surface of the mine. The principal uses of thermosyphons in the Arctic are to reduce the ground temperature to prevent potentially unstable permafrost from thawing and to increase the bearing strength of the material. The mathematical model of the physical problem, generally known as "the Stephan problem," takes into account the varying thermo-physical properties of air and the frozen and thawed rock mass, the thermal properties of the freeing fluid in the thermosyphons and the phase change of water. Finite-difference techniques were employed to determine the temperature isotherms around the thermosyphons. It was found that two rows of thermosyphons on a 10- x 10-m grid provide an acceptable design spacing for reducing the ground temperature around the mine airway.

Jan 1, 1997

By Stewart R. D, Lawrence W, Youl M. J

The trend towards contracting by major coal mining companies such as BHP Coal and MIM Ltd is examined. Reasons why this trend is occurring are discussed and the concept of partnering is examined. Two case studies are given: the Mt Owen Mine in the Hunter Valley, NSW and the South Walker Creek Mine in the Bowen Basin, Queensland.

Jan 1, 1997

By Alphonso Cornejo, Galen H. Clevenger

This bibliography was compiled in connection with an investigation of the Caron process for the treatment of manganese - silver ores , conducted by the T. S. Bureau of Mines in cooperation with the Netherlands East Indies Government . The object of this investigation was to develop a practicable method for treating the refractory manganese- silver ores found in these two countries . The results of the work will be published as a bulletin of the Bureau of Mines . This bibliography summarizes the available information on the subject previous to the investigative work embodied in the forthcoming bulletin, and may be useful to those metallurgists or others conducting work along this line .

Mar 1, 1923

By J. Raath, A. J. Fischmann, C. Spagnuol, E. D. Brooks

This paper demonstrates the use of Clean TeQ Water’s ATA® rapid dewatering technology as an alternative approach to the tailings paddock buttressing method which is currently being implemented. ATA® is a three-component system where the tailings stream is separated into fines and coarse fractions utilising a hydro-cyclone. The results from the pilot demonstrated that the use of ATA® offers significant advantages, including higher homogeneity in the buttress, higher permeability, and faster settling rates.

Apr 8, 2026

By S. Demetrio

China has a traditional segment of Copper Smelters with its own Chinese technology, typically small in size from 20.000 to 50.000 tCu/a, and they are responsible for the processing and production of more than 600,000 tonnes of blister copper per year. For occidental experts, like one of the authors, it is not so easy to believe that they are profitable, because the size and the use of old Blast Furnaces, but they are with simple and effective production lines. The authors are convinced that China has a good alternative to improve theses old copper production lines with small innovative changes in its process arrangement, jumping to higher level technology, more efficient in production, productivity and cost, assuring copper as a raw material for the country and its high speed development. The key to improve that the traditional Chinese Copper Smelter is white metal as an extra raw material as a first step doubling the copper production from raw materials and the complete replacement of concentrates by white metal (WM) in a second step increasing it four times or more as the final goal. It is not so difficult nor expensive to make it happen, but there are a couple of questions for implementing this innovation in the copper smelter industry: 1 - Will the old fashioned mentality be open to this new direction for China being the biggest copper consumer on one side, and the biggest copper Primary Producers on the other hand? and 2 - Will they be open to follow this "win-win" strategic way for both ends of the copper market? We don't know if anybody will take up the challenge to improve it but our responsibility as a consulting expert and a university professor is to put the alternative on table for others to decide whether to implement it.

Jan 1, 2007

By James A. Voigt

The efficient separation of metal species from aqueous streams by precipitation techniques requires 'a fundamental understanding of the various processes that occur during precipitation. These processes include particle nucleation, particle growth by solute deposition, agglomerate formation, and agglomerate break-up. The application of the population balance approach has been used to develop a kinetic model that accounts for these competing kinetic processes. The usefulness of the model is illustrated through its application to the precipitation of yttrium hydroxynitrate, YHN. The kinetic parameters calculated from the model equations and system-specific solution chemistry are used to describe several aspects of the effect of pH on the precipitation of the YHN. Implications with respect to the simultaneous precipitation of more than one cation type are also discussed through use of example systems: The effects of solution chemistry, precipitator design, and solvent choice are considered.

Jan 1, 1996

By H. C. M. Gordon

MR. A. D. BADOUX: I have listened to Mr. Gordon's excellent paper with great interest, as I personally have gone through some of the experi­ences he has so clearly depicted. In particular, there were a good many times when we were greatly exercised in our minds as to whether we were justified or not in closing-off certain sections in the Allan mine. The difficulty in these cases arose from the fact that a peculiar smell could be detected in these sections but at the same ti me there was no positive evidence of spontaneous combustion either from heat being apparent or from the possible indications of fire getting any worse. It was suspected that the small percentage of -carbon monoxide that could be obtained by analysis in the air in these sections, and also the peculiar odour, were emanating from the coal itself, and, in order to verify this, bore-holes were drilled in the coal and the gases released from these bore-holes were analyzed. They were found to contain carbon monoxide. After quite a considerable length of time this contained carbon monoxide gradually diminished and finally could not be detected when analyzing such samples of gas. It was our intention to follow this matter up further, as such an occurrence of carbon monoxide is practically unknown, but the sections in which these occurrences were found had to be abandoned. Mr. Gordon referred t0 a case of spontaneous combustion in the Allan . mine, and I may say that, although the section in which that occurrence took place was travelled and carefully examined every day by the colliery officials, yet nothing unusual was noticed until the fire actually took place. This tire was the cause of a slight explosion.

Jan 1, 1938

There are many compelling reasons why correct sampling schemes should be standard practice in the mining industry, yet there are numerous examples where poor sampling practices are known to exist in the business yet permitted to continue. It is not just technical issues that can be ascribed to the reasons for the continued use of incorrect methods. This paper proposes non-technical reasons why incorrect sampling practices continue, and identifies potential ways to overcome them.

Mar 1, 2010