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By D. A. Wilson

A process was developed on a laboratory scale in which a solid waste byproduct from refining of secondary lead was converted into three valuable products. Roasted lead blast furnace matte was leached with water to recover copper. This was followed by brine leaching to recover lead. Residues were finally smelted to yield pig iron. Copper was precipitated as cement copper and the lead product obtained was a mixture of pure 3PbO.PbC12.xH20 and Pb(OH)C1. Copper recovery was 89 percent and lead recovery was 96 percent.

Jan 1, 1967

A major high grade zinc deposit, Dugald River has fine-grained and complex mineral associations which provide considerable metallurgical challenges for both mineral dressers and downstream processors. A long history of metallurgical testing focusing on mineralogy and flotation concentrate production has shown that while separate lead and zinc concentrates can be produced at saleable grades, high levels of iron, and particularly manganese, are likely to place constraints on the marketing of zinc concentrate produced from deeper zones where coincidentally lode development is at its maximum. Testwork has focused on characterising the flotation response of ore types ranging from banded and stringer sulphides to brecciated ores in a variety of sulphide matrices. A high level of variability with lower than expected metal recoveries has been indicated across some of the higher grade brecciated ores. However, the dominant slatey breccia has generally provided the best results. Heavy media preconcentration testwork has been moderately encouraging and at this stage, although value adding downstream of concentrate production on-site is not seen as an economic option processing developments are being monitored on a broad front. Providing satisfactory means can be developed for handling manganese during downstream processing of the concentrate, it is not difficult to see a world-class operation emerging from the resource in the medium-term Future.

Jan 1, 1993

By R. C. Hartviksen

"The Drumbo Mine is a new gypsum mine located at exit No. 32 of Highway 401 between Woodstock and Kitchener, Ontario. The flat-lying 6-foot (1.8-metre) bed of gypsum is near the base of the Silurian Salina Formation, about 380 feet (116 metres) below surface. The mine is owned and operated by Westroc Industries Limited. A shaft, 12.5 feet (3.81 metres) in diameter, was drilled and then lined with a liner-sinking technique new to this continent. The shaft was completed in the fall of 1977. Gypsum production was started in December 1978, employing a conventional room - and - pillar method of mining.Historical BackgroundA brief mention of gypsum in the Drumbo area is included in a survey of the Ontario gypsum industry by Guillet. This occurrence was discovered in 1958 when National Gypsum conducted some widespread diamond drilling. Western Gypsum Products Limited acquired leases in 1960 and concentrated a drilling program in Blenheim Township near the village of Drumbo; 79 holes were drilled in an area of 1900 acres (770 hectares). Mining rights were then acquired for 170 0acres (690 hectares). A test shaft, 44 inches (1.1 metres) in diameter, was drilled to obtain a 50-ton (45-tonne) bulk sample. This opening will be used as an emergency escape way and for ventilation.Westroc Industries Limited, a wholly owned subsidiary of BPB Industries, has its head office at Mississauga, Ontario and operates gypsum board plants at Mississauga, Vancouver, Calgary, Winnipeg and Montreal. Other gypsum mines are at Windermere, B.C. and Amaranth, Manitoba."

Jan 1, 1983

By J. Smolensky, M. Paul

The Nordhalde is a waste rock pile resulting from uranium mining near Ronneburg, Germany. The pile contains over 27 million m3 of waste rock. Typical seepage water has a pH of 2.7 and a sulfate concentration of 10,000 mg/L. Geochemical investigations of the Nordhalde from 1993 to 1996 included drillholes, test pits, ABA and metals analyses, column tests, and a detailed review of the construction history of the pile. In 1996, eight drillholes were instrumented for monitoring oxygen and temperature. Monitoring continued for a fill year. Hourly temperature and pressure readings were taken by automated data recorder. Oxygen concentrations were measured three times per week, and periodic gas samples were obtained for complete analysis. The resulting data set is believed to be one of the most comprehensive of its kind. Effects noted elsewhere, such as thermal convection, are evident. However, unlike other data in the literature, the NordhaIde data shows a strong seasonal effect, with convection dominating oxygen transport only in the winter months. Analysis of the data allowed the amount of contaminants associated with ongoing and historical oxidation to be compared, and results were used to assess the potential effectiveness of proposed remediation measures.

Jan 1, 2000

The second annual student prize giving function of the South African Institute of Mining and Metallurgy was held in the Van der Byl Hall, University of Pretoria, on Thursday, 10th March, 1978. The main address (see opposite page) was given by Dr T. F. Muller, Chairman of Iscor.

Jan 1, 1978

By John C. LaScola, Gerald L. Finfinger, Michael A. Trevits

Methane gas is an ever-present problem facing the underground coal mining industry. Mine operators are mandated by law to maintain safe concentrations of methane gas within the mine environment. Ventilation is the method of choice used by all mine operators to reduce gas concentrations. When gas emissions are such that ventilation alone cannot control the gas, methane drainage methods must be applied. In the 1970’s, there was a concern that unprecedented gas emissions would be experienced as mine operators began new developments in the deep and gassy Blue Creek and Pocahontas No. 3 Coalbeds. Such concern was well founded as significant gas volumes are being emitted as these mining operations mature. In 1971, the U.S. Bureau of Mines began to tabulate and track the change in mine emissions. These data were extracted from the underground coal mine quarterly air quality-quantity inspections performed by the Mine Safety and Health Administration. At that time, approximately 6560 Mm3/d (231.7 MMcfd) of gas were emitted from 430 underground coal mines. It was determined however, that the mines emitting less than 2832 m3/d (100 Mcfd) contributed only 2.1 percent of the total daily gas flow. In 1988, underground coal mines emitted 8350 Mm3/d (294.9 MMcfd) from 487 mines. This report evaluates the changing nature of U.S. mine gas emissions over the last 18 years.

Jan 1, 1991

By Jesse L. Duke

Outline ?Understanding the context ?The Business, political, social and legal environment ?Recipes for Success (three Ps) ?Develop effective Partnerships/relationships ?Plan carefully ?Actively Manage the ?Process? Business Environment ?Nunavut?Impressive mineral potential ?Emerging diamond industry ?Dominated by Juniors ?NWT ?Maturing Diamond industry ?Emerging oil and gas industry ?Yukon ?Alaska Highway Pipeline ?Junior-dominated exploration and development ?Growing acknowledgement in Canada of the importance of northern resources ?Shift of thinking: north-south infrastructure (vs. East-west)

May 1, 2006

By Youliang He

Twin-roll casting is an integrated casting and rolling process that involves the continuous solidification of a melt and the plastic deformation of the solidified metal between two rotating rolls. Computer modeling is a valuable tool to help engineers understand the metallurgical process during twin-roll casting. However, commercially available software can only model either the fluid flow/heat transfer of the melt or the plastic deformation of the solid, but not both. In this study, an object-oriented finite element program was developed to simulate the steady-state fluid flow, solidification and plastic deformation of an A7,31 magnesium alloy in a horizontal twin-roll caster. The melt, the mush zone and the solid were treated as a generalized Newtonian flow in an Eulerian reference frame and different constitutive equations were employed to describe the material behaviours. The effect of operational parameters on the solidification process was discussed based on the simulation results.

Jan 1, 2010

By K. B. Young

Possibly the most complex fatigue problem associated with the development of the axial-flow 'gas turbine is discussed in its broader aspects from the metallurgical viewpoint. Reference is made to nodal patterns, interference diagrams, etc. The use of such data in analysis of a turbine :blade failure is illustrated. Special attention is given to the influence of some metallurgical variables affecting fatigue strength and, in particular, heat treatment is shown to have a pronounced effect on .the relative fatigue and creep strength properties of a nickel-chromium-cobalt base alloy suitable for turbine blade applications.

Jan 1, 1958

By A. K. Gangopadhyay

This paper discusses the effect of grinding media composition, mineral type and slurry environment on the wear rate of various grinding media (balls). Sufficient wear data have been obtained and correlated with the modes of wear determined from examination of the ball surfaces using scanning electron microscopy. Five modes of wear have been identified to be operative under certain slurry conditions for the various ball compositions studied.

Jan 1, 1984

By Antrekowitsch Jürgen

The recycling of residues from metal producing by-products has become a main field of interest in metallurgical investigations. Forced by a stricter environmental legislation and the resulting increase of landfilling costs, combined with the aim to recover as many valuable metals as possible, a lot of different processes have been developed in the last two decades. Because of the high yearly tonnage residues from the iron and steel industry like slags, dusts and sludges have moved in the center of interest. Dusts from the steel mill, containing heavy metal oxides and halides did not play a considerable role as secondary raw materials for a long time. They even contain a huge amount of leachable elements and compounds which cause noticeable problems in case of a dumping. Nevertheless, the implementation of a new landfilling regulation, including a prohibition of aboveground dumping without inertisation, caused a rising interest concerning recycling technologies for such residues. In addition, the zinc content of these dusts became higher and higher and began to play the most important role for the economy of dust recycling.

Jan 1, 2006

By Robert H. Richards

During tile summer of 1870, I had an opportunity to visit the laboratory of the late David Forbes, Esq., in London, and was much interested in a labor-saving device which he had attached to his agate mortar. The mortar was placed in the centre of a small table, and about ten inches to the right of the mortar, a post, perhaps two

Jan 1, 1879

By H. Lawson

The Mine Safety and Health Administration (MSHA) issued Program Information Bulletin P09-03in April of 2008, providing formal guidance on using programs that model the redistribution of stress during underground mining of coal. A key part of this guidance is visual observation and mapping of ground conditions. If a correlation between ground conditions and model output can be established, the model is considered to be verified, and can be used to guide mine design in similar ground. A simple scale is recommended for ranking observed roof, rib, and floor conditions. This paper discusses optimization and implementation of a ground condition rating scheme in the gateroads of a deep underground longwall coal mine. Roughly 80% of each gateroad length deteriorated in a fairly uniform manner. However, this manner varied between gateroads, as did pillar size. The implementation of a ground condition mapping program, similar to that recommended in PIB 09-03, was successful in characterizing the ground response to mining in gateroads of a longwall coal mine.

Jan 1, 2012

By S. R. B. Cooke, W. Philippoff, Donald E. Cadwell

[THE importance of contact angles in flotation has long been recognized, but little has been done to get quantitative relationships between the surface coverage of the mineral by the reagent, the length of the hydrocarbon chain, and the contact angle. It is well known that for a complete monolayer on the surface of a mineral the contact angle ? is determined only by the reagent&apos; and principally by the chain length of the hydrocarbon radical. Although for flotation the monolayer usually is regarded as being complete, early experiments of Wark and Cox2 showed that at very small concentrations of potassium ethyl xanthate the contact angle on galena changed in a continuous way from 0° to the equilibrium value of 60°. Further, Gaudin and Vincent&apos; showed a similar continuity using heptylic acid and sphalerite. This shows that with probably incomplete monolayers, ? varies with the degree of surface coverage. At the time these experiments were made it was impossible to measure the actual amount of surface coverage, especially since the decrease of the collector concentration in the liquor could be influenced by chemical side reactions. Through the use of the radioactive tracer method for the measurement of the amount of collector adsorbed on the surface of the mineral, Gaudin and Bloecher4 were able to determine accurately the actual surface coverage of dodecylamine acetate on quartz, but they did not measure any contact angles. It is believed that the relationship between the surface coverage and the contact angle is extremely important in flotation, especially as Gaudin and Bloecher showed that a 95 pct recovery is possible with a coverage of only 5 pct. Theoretical Considerations The work of adhesion W is the energy bound (in ergs per sq cm) when an interface is formed. It is determined by, the difference of the free surface energies (surface tensions) of the respective phases ?1 and ? 2 before contact and the interfacial free surface energy ?12 after contact. The definition of the contact angle permits the elimination of the unknown surface energy of the solid and hence the calculation5 of W from the surface tension of the liquid ? and the contact angle ?: [W = y (1 + cos ?)[1]] Consider a surface consisting of two components, identified as 2 and 3, 1 being the liquid. The amount of 2 in the composite surface is x, where 0 < x < 1. The respective contact angles with 1 and air are ? and ?3. The total work of adhesion of such a surface is the sum of the values of the components multiplied by their respective areas. A formal relation can be written: [W,,,=x•W2+ (1-x).WR[2] .] in which Wm is the work of adhesion of the composite surface. Eq 1 can be introduced into W2 and W3 but in the case of Wm some discussion is needed. If the two components are segregated, each component forming an integral part of the composite surface there is no physical meaning for a contact angle ?m, calculated from Wm, by using eq 1. If, on the other hand, the area of each patch of the components is small in comparison with, say, the diameter of the bubble used in measuring, it could be expected that ?m would have aphysical significance, because of the action of the surface tension of the liquid-gas interface tending to smooth out sharp corners. How small these patches would have to be is difficult to predict, but by using composite surfaces with microscopically]

Jan 1, 1952

By Samuel G. Bonasso

The article by Benavides and Schuster provides an in-depth study of this transportation alternatives for a four-mine complex in western Kentucky. The examination of aerial tramways was not undertaken as an alternative solution. We feel this is an oversight since industrial ropeways are competitive with both belt conveyance and overland truck hauling. In fact, there are aerial tramway system, operational today, which are 100 years old and operating with some original components. Maybe unfortunately, there are no fixed rules or guidelines whereby the most cost-effective means of transporting and handling material for a given situation may be selected. Each situation must be evaluated m the variables that influence the selection of the desired alternative can be clearly defined. However, there are in-place industrial ropeway system that have proven economically feasible over a range of 1.6-50 km (1-31 miles). The more difficult the terrain, the greater the cost efficiency.

Jan 1, 1984

By J. W. Downey, M. V. Nevitt

DURING the course of the present investigation of alloy phases involving transition metals, phases were found in the systems Os-Ta, Os-W, and Ir-Ta. The (Os, W) phase was also recently reported by Raub.1 Pertinent information is given in Table 1. The approximate composition range of sta- bility was determined metallographically on arc-melted buttons that were annealed 72 hr at 1200°C and water quenched. X-ray powder patterns were obtained with a 114.6 mm diam powder camera using filtered copper radiation. The composition for (Os, W) given by Raub (66 atomic pct W) is in agreement with the composition range reported here. However, the lattice constants reported by Raub are: a0= 9.913±0.007, c/a= 0.515. The reason for the discrepancy between the lattice constants reported by Raub and those given here is not known. Acknowledgments The authors wish to thank M. H. Mueller and H. W. Knott for assistance with the X-ray diffraction work, and R. A. Morris for the preparation of the alloys. This paper is based upon work performed at the Argonne National Laboratory under the auspices of the Atomic Energy Commission.

Jan 1, 1958

By Dae S. Young

A new probabilistic approach is introduced for slope stability analysis including adverse impact of blasting vibrations. The material strength within a slope area is randomized in this bi-variate joint probability analysis. To be a completely general engineering method, the new probabilistic approach employs the random variable transformation technique: the Hermite model of the Gaussian transformation function, which transforms the experimental histogram of strength values to the standard Gaussian variables. Because bi- normal joint probability is analyzed on the true probability region projected on the Gaussian transformed variable plane, it is an exact solution of slope stability based on the available sample data. Details of the probabilistic approach are given through a case study on an iron ore mine. The case study demonstrated that the probabilistic approach is effective and simple enough to be a routine engineering practice for slope analysis.

Jan 1, 1984

By Francisco Gallo

La transformación de una empresa no solo depende de la capacidad de compromiso y cambio de la alta gerencia, sino se relaciona con la adopción de una tecnología iexitosa que transmita a la organización, un conjunto de paradigmas, procesos y política que el tiempo amerita. En este sentido, el presente trabajo describe el desarrollo de la tecnología informativa en la empresa minera Atacocha a través de las áreas de actividad productiva y administrativa. Para ello, es necesario que la empresa realice ajustes en su organización, procedimientos y políticas, de forma que se pueda aprovechar la inversión de una tecnología. Asimismo, los impulsores del cambio deben hacer el esfuerzo de identificar los medios por los que las premisas sobre las que se basa el cambio y la instrumentación de los mismos, permitan ser absorbidas gradualmente por la organización.

Sep 13, 2001

By E M. Jones

On 26 June 2000 a hydraulic fill retaining barricade failed at the Bronzewing mine in Western Australia. The barricade failure resulted in the release of 19 000 m3 of saturated hydraulic fill into the mine, which caused the deaths of three miners. Following this tragic accident, the practices and procedures of mines using hydraulic fills came under intense scrutiny by regulatory bodies and mining companies. At this time, the use of hydraulic fill at NormandyÆs zinc/copper Scuddles mine was suspended and waste rock became the sole backfill material in use underground. By 2003, development of the mine adjacent to Scuddles, Gossan Hill had progressed to a point where a self-supporting fill material was required to enable full recovery of high-grade ore. Cemented hydraulic fill (CHF) was identified as the optimal fill type and work began on designing appropriate management procedures and controls to ensure the safe implementation. This work included definition of the fill properties, plant design and construction, reticulation system design, design of stope barricades and drainage systems and fill placement control and monitoring practices. CHF placement began on 16 July 2004 and has continued to date. Significant operational experience has since been gained in areas including plant performance, fill product quality assurance, barricade construction, stope drainage and in situ performance.

Jan 1, 2008

G. W. TRAER (author&apos;s reply to discussion*).-Prof. Parr&apos;s discussion develops two points, upon which it seems desirable to comment. First, as to putting through a large enough tonnage to secure economic operation. At each manipulation of each oven 1500 1b. (680 kg.) of coal will be charged and the resultant coke discharged from a like amount of coal. . Sixteen slabs will be discharged at each manipulation, each approximately 5 ½ in. by 11 in. by 6 ft. (14 cm. by 28 cm. by 1.8 m.). The operating schedule of a commercial plant, based upon our observations and calculations, indicates a "through put" of at least 12 tons of coal per day for each oven. We have made these figures conservatively and feel confident of materially exceeding them in a fully developed operating system. Our oven plant, with containers, will not cost as much as high-temperature plants of the same capacity. They do not require container equipment; but this is much more than offset by the cost of the great basal heat regenerative flues. Our operating requirements are quite susceptible to the application of mechanical devices and we believe our labor cost will be well within the necessary limit. Second, as to Fig. 1 in my paper, showing the specific gravity&apos; of the tar. It Was not intended to show that the specific- gravity of -the tar rises With decreasing heat, since of course the contrary is the fact. One of the curves shows the relation between temperature and specific gravity and the other the relation between temperature and- yield. Our consulting engineer prepared the chart according to his customary method for showing two dimensions.

Jan 1, 1919