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By G. L. Oldright

The data in this paper were collected at the Trail smelter of the Consolidated Mining & Smelting Co. of Canada, Limited, through the courtesy of S. G. Blaylock, vice president and general manager; James Buchanan, smelter superintendent; George Murray, assistant smelter superintendent; and the staff members given in Paper XI, Report of Investigations 3243. INTRODUCTION This paper is the thirteenth of the series on Smelting in the Lead Blast Furnace, and the third of the series on Handling Zinciferous Charges. Tyro other papers have been written on the Rate of Descent of the Stock Column, and Formation of Accretions. These are Reports of Investigations 2963 and 3094, for the Tooele plant and the Bunker Hill plant, respectively.

Jan 1, 1934

Talk some about your background. Mining, particularly coal, runs in the family. I come from a mining family, one generation re-moved. Both of my grandfathers worked in the coal mines. My mother?s father had worked as a coal miner in the South Hills area of Pittsburgh after coming to America from Croatia. My father?s father (who died of black lung long before I was born) had been born in America and worked as a mine foreman and superintendent in mines just outside the Pittsburgh area. My father often talked about when, as a child, he accompanied his father underground on Sundays to check the mine pumps. While I never expected to go into mining, I often read some of my grandfather?s books on mining technology that my father had kept. I started college at Penn State and drifted into mining engineering as my third declared major. I was finally realizing the importance of a career choice. I?ve never regretted that decision. One of my children, Mark, has followed me into mining engineering, much to my surprise and pride. Evidently, he had been listening to the many conversations I had with friends and colleagues in the industry and never considered any other career path. He has since married another mining engineer, Kray Davis Luxbacher, so we truly have a mining family and can talk mining when we get together. My other children are in more mundane lines of work and rapidly tire of the mining discussions. I?ve worked for operating companies: Pittsburgh Coal Co. (then a division of Consolidation Coal Co., and a company I believe both of my grandfathers had worked for), Island Creek Coal Co., and a research organization: Occidental Research Corp. I am now with Glenn Springs Holdings Inc., dealing with legacy issues (primarily environmental) related to Occidental?s previous mining operations (coal and minerals). As such, I have a broad view of the industry and the critical changes that are shaping our industry.

Jan 1, 2008

By Michael V. Markel

This report summarizes work performed under USBM Contract No. J0100047 revealing the performance characteristics of a composite-type resilient screen deck. The ability of the composite to perform or compete with steel in noise attenuation and longevity was of interest. Tests were conducted at the River King Preparation Plant of Peabody Coal Company. This facility was chosen because it provided parallel process flow and met standard coal cleaning requirements. Comparisons could be made between the adjacent resilient and steel screen decks under similar operating conditions. Noise reductions of 1-6 dBA were realized in the near field. Although the test period did not determine resilient screen life, indications are favorable for their longevity.

Jan 1, 1981

By Neng-Wen Yu, Shau-Jun Zhu, Ji-He Wei

The desulfurization process by powder injection and blowing in the RH refining of molten steel and its mechanism have been considered and analyzed. Based on the two-resistance mass transfer theory and the mass balance of sulfur in the system, a kinetic model for the process has been developed. The related parameters of the model, including the mass transfer coefficients and the effective amount of powder in the molten steel being treated for desulfurization, have been more reasonably determined. Modeling and predictions of the process of injecting and blowing the lime-based powder flux under assumed operating modes with the different initial contents of sulfur and amounts of powder injected and blown in a RH degasser of 300 t capacity have been carried out using the model. The relevant circulation rate of the liquid steel and the powder injection and blowing rate were taken to be 100 t/min and 150 kg/min, respectively. The initial contents of sulfur in the liquid steel to be treated and the amounts of powder injection and blowing were respectively assumed to be 0.007, 0.006, 0.005, 0.004, 0.003, 0.002 mass-% and 10, 8, 6, 5, 4, 3 kg/t-steel. The total treatment time for desulfurization under each mode was set up at 24 min, equivalent to eight circulation cycles of the liquid steel to be treated. The results indicated that the predictions made with this model are in good agreement with some data of the industrial experiments and practice. Injecting and blowing the lime-based powder flux with the composition of 85 mass-% lime (CaO) + 15 mass-% fluorspar (CaF2) of 3-5 kg/t-steel, it is possible to decrease the sulfur content in the molten steel to ultralow level below (5-10)x10·4 mass-% from (60-80)x 10·4 mass-%. The total treatment time needed will appropriately be 12-20 min. Intensifying the powder injection and blowing operation and increasing the circulation rate of the liquid steel may effectively' raise the rate of the process in RH refining. The model may be expected to offer some useful information and a reliable basis for determining the reasonable process parameters and help in optimizing the technology of desulfurization by powder injection and blowing in the RH refining of molten steel.

Jan 1, 2000

Jan 1, 1891

By Eugene (Gene) Bounds

The Mining industry faces many challenges, one of which is the demand to communicate over a variety of media, be it visual, sound, voice, data or any combination. Over the years multiple infrastructures have been put in place to overcome environmental obstacles and address these communication needs. A mine is an aggressive environment for electronic equipment and as such only the best quality equipment can perform under those special conditions of e.g. temperature, dust and humidity. Siemens Canada and its partner LComm will discuss a mining solution using a unique combination of technologies based on fibre optics, standard communication interfaces, passive antenna infrastructure and wireless services. The presentation looks at maximizing the use of infrastructure, reducing costs, addressing difficulty of communications coverage above and below the surface and the capability to future proof the capital investment as new requirements and applications are identified. Discussion will address: Wireless voice, high speed data Data acquisition for process control from sensors Video for remote control and security Miner safety and location Timely receipt of large volumes of information

Apr 1, 2005

By H. A. Gorrell, S. R. L. Harding

"The potash beds in the Saskatchewan portion of the Williston Basin occur in the upper portion of the Prairie Evaporite formation of the Devonian Elk Point Group. They represent the late stage of a major evaporitic cycle. Two other evaporitic cycles are known in overlying beds, but these apparently never reached the stage of potash salt deposition. The basin in which salt deposition took place extended from the northwestern corner of Alberta southeastward across Saskatchewan into Manitoba, North Dakota and Montana. Deposition of potash salts was apparently restricted to the southeastern portion of the evaporite basin. On a regional basis, five major stratigraphie divisions of the potash-bearing strata have been made. Locally, several of these units may be divided into correlatable sub-units. The potash-bearing strata are separated and overlain by predominantly halite layers of varying thickness. Cross sections show the regional correlation of the potash-rich zones, and maps show the present distribution of the individual potash-bearing zones and the areas of richer development for each zone. The maps tend to substantiate the interpretation of considerable subsurface solution of salt and potash beds."

Jan 1, 1967

By Maísa Villela Freire

Refratários MgO-C encontram-se entre os mais adequados para o uso na linha de escória de panelas para aço líquido. Seu comportamento, nesta aplicação, depende de fatores termodinâmicos e cinéticos. Métodos de cálculo termodinâmico para avaliar o potencial de degradação de refratários MgO-C por escórias e pela atmosfera são revistos brevemente. Tais métodos envolvem, em geral, premissas importantes sobre a quantidade de materiais envolvidos. Para avaliar um método mais simples, foram escolhidos dois tijolos MgO-C e duas escórias típicas do processo da CSN. Estes tijolos e escórias foram caraterizados, neste trabalho. O método apresentado consiste na realização de cálculos de equilíbrio em que a principal variável é a fração de escória em uma mistura hipotética com o refratário. Para a composição do refratário foram empregadas (a) composição média e (b) composição da matriz do tijolo. Os resultados indicam que é possível realizar previsões iniciais quanto à reatividade do refratário e determinada escória de forma simples. Os cálculos, evidentemente, não substituem testes cinéticos e testes em escala industrial, em vista da complexidade dos sistemas em questão.

Aug 17, 2017

By Mark Flower

A 20L ignition test chamber has been used to test suspensions of 7 UK and world traded coals in air and O2/CO2 mixtures typical of oxy-combustion conditions. The coals varied in rank from sub-bituminous to bituminous and were tested in varying concentrations from the ignition limit to 400g/m3. Following each successful test the combustion residue was collected, weighed and analysed within a thermogravimetric analyser, allowing Q factors to be estimated. The ignition limit varied slightly in air, but was mostly around the 200g/m3 level. With the exception of Coal C, which was much harder to ignite, it correlated roughly with coal rank. The ignition limit changed significantly with O2 concentration when in mixed O2/CO2 gases. Only a few high volatile coals ignited in 21% O2/CO2 v/v, and then only with a 2500 J, rather than a 1000J, igniter. An increase in O2/CO2 levels to 30 or 35% gave ignition patterns similar to those carried out in air with a further increase to 40% having little additional effect. In addition the minimum ignition concentration decreased with increase in O2. Heterogeneous combustion or gasification of the coal by CO2 appears to be confirmed by comparing weight loss results for air and O2/CO2 mixtures respectively for an equivalent peak pressure rise.

Jan 1, 2009

By R. V. Typliski, G. J. Labarre

"Hudson Bay Mining and Smelting Co., Limited, Flin Flon, Manitoba, Canada, has developed a metallurgical wastewater treatment system employing two-stage lime neutralization, sludge recirculation and conventional mechanical thickening.Laboratory investigations, initiated in 1970, led to the construction of a pilot-scale minewater treatment plant, at Schist Lake Mine, in early 1971. This plant, treating 600 cubic meters/day wastewater containing 30-60 mg/l zinc, demonstrated metal extraction efficiencies of 99% under normal operating conditions.On the basis of this pilot work, a second pilot-scale treatment system was established in 1975 at the Flin Flon metallurgical plant to treat zinc refinery process waste water. Through numerous improvements, including automatic control equipment, the system has evolved to a full-scale operation capable of treating 800 cubic meters/ day wastewater containing 4-11 gm/l zinc. Treated effluent contains 0.2-20 mgll zinc. Hydroxide sludge produced returns to the metallurgical process for recovery of metals while clarified effluent discharges to waste.With the system, Hudson Bay Mining has achieved its original goal: the reduction of environmental contamination, while realizing ii return from metal recovery."

Jan 1, 1980

By Larissa Koroznikova, Steve Durkin, Patrick Bouwmeester, Michael Tuck

In currently used mining methods, blasting techniques often causes dilution of valuable ore and results in costly processing requirements. In the context of narrow vein mining of thin and highly concentrated orebodies there is a need of a mining method that can reduce dilution in order to remain economically viable. This research project explored the viability of a new mining technology, thermal fragmentation, in narrow vein mining. Thermal fragmentation technology uses a flame jet to produce extreme heat that spalls the surrounding rock to a strategically located drill hole, as an alternative to traditional blasting. This paper creates a net present value (NPV) model of a mining method using thermal fragmentation, as well as for an existing method used for narrow vein mining; comparisons and evaluations were made regarding the feasibility of the new technology. It was found that while overall costs for thermal fragmentation were relatively high, reductions in wages, haulage and processing costs, as well as increased productivity and ore recovery, meant that the new method would improve the financial performance of any operation. These results identify that there is an opportunity to introduce the thermal fragmentation technology to narrow vein mines within Australia, in order to lower costs and increase profit.

By Alichurch P. D

Perseverance nickel deposit is located at latitude 27¦ 491S, longitude 1200 42'E, 330 km north of Kalgoorlie, Western Australia. Gossanous outcrops were discovered in April, 1971, and after further detailed surface investigations, percussion drilling led to diamond drilling by June, 1971. Up to December, 1972, 127 diamond holes totalling 45,590 m were drilled to indicate 33 million tonnes averaging 2.2% Ni using a 1% cut-off grade. The deposit occurs in a lenticular ultra- mafic unit emplaced in metasediments locally forming the eastern flank of the Archaean green- stone belt trending NNW from Leonora to Wiluna. To the east a major strike fault separates the metasediments from gneiss; westwards there is a sequence of metavolcanics with further ultra- mafic units. Length of the lens is 3500 m and it attains a maximum width of 800 In. The eastern contact is moderately regular, but the western contact is prominently embayed. Local strikes are NNW, and dips are steeply W. A set of strike faults cuts the ultramafics and enveloping quartzites. These are normal faults, parallel to the major eastern fault, dipping 65-70¦W. They impart a serrated pat- tern to the sub-outcrop of the western contact. Massive serpentinite is the dominant rock in

Jan 1, 1973

By W Akpan

The Royal Bafokeng community in South AfricaÆs North West Province represents a unique case in Sub-Saharan Africa in terms of its positioning in the natural resource economy. It receives royalties directly from mining firms for the extraction of Platinum Group Metals, which include platinum, ferrochrome, rhodium and palladium. In 2007, royalty income of about R290 million (approximately US$32.2 million) was reported. Such direct revenues have enabled the community to invest in educational, medical and other social infrastructure, thus complementing governmentÆs social provisioning efforts. Indeed, the Bafokeng community owes its present-day modernisation efforts to mineral rights, and in particular, the legal-institutional arrangement that has enabled it to play an active role in South AfricaÆs lucrative extractive economy. However, the distribution of platinum wealth in this community is not only uneven, but also appears to have had little impact on the broader socio-economic conditions in the community. Despite claims by community leaders of heavy investment in education and skills development, the community continues to be faced with very high levels of unemployment, illiteracy, sprawling informal settlements, poor access to medical facilities and malnutrition. This paper examines the sociological paradoxes and contradictions thrown up by the approach adopted to involve community members in the mobilisation of mining royalties for developmental ends. The central argument is that the current æmodelÆ contradicts the communityÆs stated goals of using platinum wealth to drive up broad-based development and modernisation. This is mainly because it leaves out the vast majority of community members, who are uneducated and unskilled. The core analysis is based on pilot data from an ongoing study in the Royal Bafokeng community.

Jan 1, 2009

By Jedson Alessandro Damasceno

Atualmente, a maioria dos pátios utilizam recuperadoras com roda de caçambas para remover o minério das pilhas de estocagem. Tipicamente, estas máquinas são operadas manualmente, com todos os movimentos controlados por operadores, o que faz com que o processo seja totalmente dependente de sua experiência, tornando difícil manter o processo em operação ótima. Para alcançar uma melhor performance, foi implementado um sistema automático que controla todos os movimentos de recuperação. Um importante desafio encontrado durante a construção dessa solução foi a de estimar a taxa de recuperação em tempo real, uma vez que esta informação é essencial para o algoritmo que controla o movimento de giro da máquina. Uma medição real dessa taxa está disponível, mas, a balança localizada na lança fica distante da roda de caçambas. Em outras palavras, a medição real está disponível com um grande atraso (aproximadamente 13 segundos). Este delay é inaceitável para o algoritmo de controle que necessita de uma medida em tempo real da taxa de recuperação na roda de caçambas. Diante disso, foi necessário implementar um sensor virtual. Este sensor foi implementado usando um sistema neuro-fuzzy para estimar a taxa de recuperação em tempo real utilizando outras variáveis disponíveis, tais como a pressão na roda de caçambas e medidas de penetração obtidas por radares. As estimativas obtidas ficaram muito próximas dos valores reais, e este sensor pôde então ser utilizado pelo algoritmo de controle.

Aug 17, 2017

By Daniel I. Carey

Current and potential dragline reclamation usage was evaluated for the U.S. coalfields based on data gathered and analyzed during field surveys, literature reviews and contacts with manufacturers. It was concluded that current mining plans have been adapted to federal and state strip mine and reclamation laws in ways which limit the potential for dragline reclamation systems at active mine sites. At abandoned conventional contour mine sites in steep-sloping areas such as central Appalachia, however, it was found that dragline reclamation systems have great potential application and may be the only practical solution to many reclamation problems. Alternative dragline systems were examined for restoring abandoned sites, and it was concluded that a tower excavator system offered superior characteristics and should be evaluated and developed under field conditions. A testing program was developed to provide a framework for the monitoring and analysis of cost, production and environmental data during a field demonstration of a tower excavator system.

Jan 1, 1981

About 90 per cent of the pre-mining BIF-hosted iron ore resource of the Hamersley Province of Western Australia is of the Phanerozoic supergene martite-goethite type. The remaining ten per cent formed as supergene deposits at ~2000 ¦ 200 Ma, and were later modified by burial to form the Proterozoic martite-microplaty hematite ores. The supergene-metamorphic segment of this general unified model has been challenged by three recently published hypogene-based genetic models for the hematite ores, all requiring meteoric oxidation to produce the ore. The most recent and detailed, by Taylor et al (2001), is based on data from the small Southern Batter and North deposits of the Mount Tom Price mine. The authors proposed that during Stage 1 æoverpressured bicarbonate-saturated basin brines from the dolomite aquifer of the Wittenoom FormationÆ at 150 - 250¦C, dissolved free silica from BIF to produce a stratigraphically thinned, magnetite-carbonate-silicate-apatite rock. In Stage 2, meteoric oxidation of siderite to secondary microplaty hematite + ankerite, and magnetite to martite, at unspecified elevated temperatures and pressures, was followed by carbonate leaching (Stage 3). Finally, during Stage 4, weathering with removal of apatite, produced the typical low-phosphorus, porous martite-microplaty hematite ores of the Tom Price-Whaleback type. However, evidence of both microplaty hematite and martite reduced to magnetite, and of infill silica, apatite, and ferroan chlorite, with late-stage pyrite, in the pore space of martite-microplaty hematite ore, shows that the hydrothermal activity at Mount Tom Price is a post-ore event. Neither pyrite nor ferroan chlorite could resist the oxidation required to form hematite ore. Recrystallisation of microplaty hematite in these infilled zones to a typically coarser form than present in most of the normal ores, is a further supporting factor. A more credible, post-ore alternative to the hypogene genetic model is suggested here. Re-exposure to leaching by ground water of the metamorphosed ore deposits in the Phanerozoic resulted in the partial removal of remnant goethite. Localised modifications in the porous BIF/ore contact zones were driven by exothermic oxygen/pyrite/carbon reactions in the footwall Mt McRae Shale. Cool descending oxygenated meteoric water in the permeable ore horizons, acted as one limb of a thermal convective cell. In the other limb, heated reducing solutions rose through the permeable contact zones, to produce the observed localised modifications of BIF and ore. Expelled silica from the carbonatised BIF invaded adjacent porous ore to form erratic silicified ore zones, and to produce the local quartz vein systems found in the associated overlying BIF.

Jan 1, 2002

By Feng Wang, Guojing Shi, Yangyang Xie, Zizong Zhu, Qiang Wu

The coal chars from northwestern part of China are characterized with high reactivity and low strength after reaction. Four type of coke-making coals selected from northwestern part of China were studied by proximate analysis, ultimate analysis, vitrinite reflectance analysis, and FTIR with curve-fitting analysis to obtain information on their chemical composition and chemical structure. The results show that the studied coals have relatively high values of final contraction of coke residue index (x) and relatively low values of maximum thickness of plastic layer (y) and average vitrinite reflectance. Based on the curve-fitting analysis of FTIR spectra, the aliphatic carbon (Cal), the aromatic carbon (Car), and the molecular structural parameters such as CH2/CH3, fa, Hal/Har, and (R/C)u are determined. The results of curve-fitting analysis indicate that the studied coals are characterized by a large amount of oxygen-containing functional groups and aliphatic side chains.

Mar 1, 2018

By Griffith. F. E., Glei

"INTRODUCTION For many years protective grounding of electrical equipment has been advocated as a means of safeguarding equipment against damage and of minimizing shock hazards to persons. Several codes are in effect covering in considerable detail the items to be observed in obtaining effective grounding in and about industrial plants. Although the coal-mining industry does not have a comprehensive code of its own covering the grounding of electrical installations, a number of States and individual coal-mining companies have issued codes, standards, or rules that include certain requirements with reference to grounding. As early as 1916, 4/ and again more recently, 5/ the Bureau of Mines recommended grounding, particularly as a means of preventing shock to men working on or around electrical equipment.It is common knowledge among electrical engineers of public utility and mining companies that connecting a wire from the frame of a machine to a rod or pipe driven into the earth does not necessarily assure desired protection of surface equipment. In fact, it has often been found necessary to use several interconnected rods and to treat the surrounding earth with salt or other chemicals before the connection to earth would have sufficiently low resistance to give satisfactory results. Even these expedients have not produced the desired results in some localities. It has also been found that ground connections initially having a low resistance may attain high resistance during some seasons of the year. In spite of such difficulties with surface equipment, it has sometimes been assumed that a mining machine resting on the floor in a coal mine is grounded by virtue of its contact with that floor. It has also been assumed by persons endeavoring to comply with grounding requirements that a peg or rod driven into the mine floor would provide a sufficiently low-resistance contact with the earth to be satisfactory as an electrode for connecting the grounding wire from frames of equipment. That both assumptions may be wholly untrustworthy has been proved by the authors in actual tests with underground machinery."

Dec 1, 1943

By John B. Gayle

The Bureau of Mines has designed and constructed an experimental coke oven, using a commercial oven as a model where practicable. Because the rate of carbonization is important in determining the quality of the coke produced and may affect the "mount of pressure developed during carbonization, particular attention was given to those elements of the design that govern the heat transfer to the charge. The new oven deviates in design from most existing test ovens in that the charge is full width (17 inches), the heating walls ore constructed of 4-1/2-inch silica brick, and zoned, heat-input arrangements compensate for heat losses at the ends, top, and bottom of the charge. This report describes the oven, which was designed by H. S. Auvil and installed under his direction, at the Southern Experiment Station, Tuscaloosa, Ala., while he was supervising, engineer, Coke Section. It gives the results of a limited number of carbonizing tests. These results indicate that the main objective in designing and building this oven, that off duplicating commerical, slot-oven carbonizing conditions, has been accomplished; if coke-discharge conditions simulate commercial-oven conditions, the cokes from the experimental oven arc very similar to oven coke, in soma tests being fully as close is duplicate tests from a Angle batch of coke.

Jan 1, 1952

By Bruce F. Grant

This report discusses research being done by the Petroleum and Natural Gas Branch und the Applied Physics Branch of the Bureau of Mines to deter-mine the most effective uses of explosives in shooting oil and gas wells, as measured in terms of rates of production from the wells. An experimental investigation of the effects of detonating explosives in shallow holes drilled in rocks, chosen to be similar to those forming oil and gas reservoirs, forms the basis of this study. Records obtained from strain gages placed in the rock around the experimental shots permit determination of the generation and propagation characteristics of the strain wave. Water-injection tests made on the test holes before and after shooting allow the increase in fluid conductivity resulting from the shot to be determined. By rotating these data to the physical properties of the rock, and by conducting shooting experiments over the range of rock types common to oil and gas reservoirs, it is expected that relationships between the fluid conductivity and the properties of the explosive and rock can be developed and used for designing efficient shots for oil and gas wells. Four series of experiment.al tests were completed during the summer of 1949 and are described herein. The results of these tests confirmed the feasibility of the experimental approach and permitted outlining the plans for future research discussed in this report. This report is presented to acquaint industry with this research program and the progress to date, so that the Bureau may have the benefit of suggestions from interested readers.

Jan 1, 1950