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By E. H. Dudgeon

In order to make increased use of automation in copper smelting, it is evident that a useful first step .world be the accurate determination of the copper end point in the converter operation. After laboratory tests, the copper end points in a copper converter at Gaspe Copper Mmes Ltd. were determined without reference to melt samples or other observations. The results indicated that the rapid measurement of the S02 level in the gas released from the converter has potential as a new and independent method of determining the copper end point in converter operation.

Jan 1, 1966

By Carl Pelletier

The Sigma-Lamaque Complex is considered a lode-gold deposit characterized by narrow vein structures, which have been mined historically by underground methods. In addition to the narrow vertical structures, mining also took place on horizontal veins, ?North Dipper? veins and dykes mineralized with sub-horizontal veins and stringers. Over the 60 + years of production, mining took place to a depth of 1.8 km. The upper portion of the deposit was considered all but exhausted, when viewed from an underground mining perspective. The year 1998 is considered a turning point for the Complex when a small open pit was mined at Sigma. The resource evaluation methods used underground were applied to surface mining, which allowed small pits to be mined. The resource evaluation method considered only the narrow vertical structures and was not well adapted to open pit mining. As a consequence, resources were consistently under evaluated. It became clear that a new geological approach was necessary to more accurately define resources (i.e., what was being mined). In order to integrate all characteristics (geometry, mechanics and chronology) of this complex lode-gold deposit, a new geological model was proposed. Due to this new approach, dating to February 2000 and updated in December 2000, the reserves evaluated in the first 180 meters now stand at 15 million tonnes @ 2.61 g/t Au (1,265,350 oz). Those reserves cover an east-west corridor extending 1,500 m by 750 m.

May 1, 2001

By R. T. Jones

"Technical publications in the field of mining and metallurgy have existed for a long time. Recent developments in electronic publishing on websites make it possible to disseminate information more widely and cost effectively than before. Professional societies have an opportunity to serve their members and their industry by publishing high-quality peer-reviewed papers on their websites as well as in printed form. Older publications can be scanned, and optical character recognition can be used to provide searchable text. Various business models exist around this process. This paper outlines the approach used by the Southern African Institute of Mining and Metallurgy (SAIMM) to provide free open access to their journal papers and conference proceedings, as well as the work being done by OneMine.org to collect technical papers from a number of international societies and make them available to subscribers via a large database. An approach is outlined that should be of benefit to authors, readers, and society at large.INTRODUCTIONGeorgius Agricola (1494-1555) was not the first writer on the subjects of mining and metallurgy, but is well known as the author of De Re Metallica (‘of things metallic’ or ‘on the nature of metals’), a book that documents and illustrates the observations he made in the course of his extensive travels in the 1500s. Agricola wrote extensively about mining methods and metallurgical processes that were in place in the Middle Ages. The original Latin version of De Re Metallica was published in 1556, the year after Agricola died. It was translated into English by Herbert Hoover, a mining engineer and later President of the United States, and his wife Lou Henry Hoover, a geologist and classicist. The English version of De Re Metallica was published in 1912."

Jan 1, 2012

By D. H. Ryan, J. T. Graham, A. Navarra, J. A. Finch, S. Somot

Pyrrhotite (Po) is widely considered to be the most significant mineral in the self-heating of sulphides. It is therefore desirable to determine the amount of Po in mineral samples. This is commonly accomplished through x-ray diffraction (XRD) or quantitative evaluation of materials by scanning electron microscopy (QEM-SEM). This paper introduces another quantitative method based on Mossbauer analysis that requires limited sample preparation and has the additional potential to detect the sulphur/iron ratio within Po. The technique is explored using pentlandite/pyrrhotite mixtures.

Jan 1, 2009

By W. Leblanc, J. C. Marsh, D. Kettle, J. Tompkins, G. Hartley

"The Lingan Mine is the newest of the four operating collieries of the Cape Breton Development Corporation and is located on the east coast of Cape Breton Island. Development of slopes began in 1969 using four Dosco Roadheaders. Production commenced in October 1972, when a partial extraction section utilizing a continuous miner, loader and shuttle car was installed. A second Joy unit is scheduled to begin production early in 1973. This paper describes the production and development operations, the ventilation system and the equipment in use at the mine."

Jan 1, 1973

By Marcio Luis S. Godoy

The Salobo Project will be the first Vale operation to use an HPGR mill to process copper-gold ore. The mine is located in Para state, southeast of the Amazon region in Brazil. The circuit was designed to treat 12 million metric tons per year of finely disseminated sulphide ore with high hardness. The comminution circuit comprises a gyratory primary crusher, secondary crushing utilizing two cone crushers, two 2 x 1.5 m HPGR operating in closed configuration with 6 mm screens, followed by two 26 x 40 ft ball mills. The concentration circuit consists of two rougher flotation stages using mechanical cells, regrinding with vertical mills, three cleaner stages with columns and one cleaner scavenger stage in mechanical cells. The concentrate is dewatered, filtered and transported by trucks and train to the port, to be exported. The circuit was designed on the basis of data obtained from a comprehensive laboratory and pilot plant campaign. The ore variability was assessed through simulation using data from a drilling core characterization program. The start-up of the industrial plant is planned for 2011. This paper describes the main aspects of circuit design, as well as information related to the beginning of the project construction.

May 1, 2010

By S. G. Hardcastle

The effects of air velocity in promoting cooling through the evaporation of sweat generated when working at a high metabolic rate and/or in hot environments is well known. Many of the environmental heat stress indices consider the effect of air movement directly or indirectly within their determination, be it through the use of a specific instrument i.e. a wet-bulb globe temperature meter or Kata thermometer, or inclusion of in the calculation of a stress index, including the effective temperature, air cooling power, thermal working limit, ISO 7933?s predicted heat strain model. Within these models, ambient air temperature, relative humidity and barometric pressure are also considered in varying degrees to quantify an airstream?s capacity to evaporate sweat. Deep mine studies have shown cumulative increases in heat exhaustion rates with both decreasing air velocity and decreasing air cooling powers. However, despite a capacity to cool, the resultant cooling is very dependant on sweat production and its availability for evaporation; these are included where sweat rates and skin wettedness are considered. The first depends on hydration and physiological factors whereas the second is more an engineering factor related to the degree of clothing required. As sweat rates deteriorate with aging, the benefits of evaporative cooling potential can similarly be expected to be diminished. This paper continues to report upon on-going physiological studies exploring the potential for heat stress in deep underground mines through the simulation of mining activities in environmental chambers and a human calorimeter facility. The focus of this paper is to introduce preliminary data suggesting that increasing air velocity (0.5, 1.5 & 3.0 m/s) is beneficial for young subjects (22 ± 1 yrs), as indicated by lower core and skin temperature measures and heart rate during an intermittent work protocol, and then show a lesser benefit for older subjects (62 ± 2 yrs). Both subject groups performed the same task under the same environmental condition (35°C, 60% RH) wearing a standard mining ensemble. The study similar to others being performed under the Deep Mining Research Consortium funded research continues to provide evidence that a greater understanding of heat management processes is required and that worker education is critical as environmental measures and health and safety regulations may not be expected to include all demographic factors such as age, sex and health which are known to affect human thermoregulatory response.

Aug 1, 2013

By D. L. Morgan, J. A. Butterfield

"Geological data, production trends and current projects underway suggest that enough molybdenum will be available from more diversified sources to meet the world's growing demands. The growth in molybdenum consumption has been primarily related to its beneficial effects as an alloying agent in steel. This rapid growth has been deliberately fostered by stable prices, adequate supply and application research. The molybdenum industry is now in a process of change which has been seen in several other metals, such as aluminum and nickel. As supply sources have become more diversified, the market has become more competitive. The recent drop in consumption has led to excess production capacity, accumulation of substantial producer inventories and increased market uncertainties. While consumption is expected to increase in the next two to three years, it will take some time to absorb the excess capacity and inventory. The increased proportion of by-product capacity indicates that prices may become more variable. Producer discipline will be required to prevent serious price erosion in times of surplus. Future prices may not continue to increase with inflation. For the longer term, several factors favour the increased consumption of molybdenum. Engineering requirements are becoming more severe and molybdenum alloys can help to meet these changing needs. In addition, consumers can rely on a large and increasing supply of molybdenum. A 7 per cent growth rate in consumption can probably be sustained through the next decade, but new applications and reasonably stable prices will be needed to make this possible."

Jan 1, 1972

By W. H. MacLean, P. J. MacGeehan, A. J. Bonenfant

"The Norita deposit is an Archean volcanogenic-exhalative Fe-Zn- Cu sulphide accumulation of the distal type, consisting of six overlapping stratiform massive sulphide lenses, interbedded with exhalative cherts and thin pillow basalt flows, which formed down-topographic-slope from a mineralized hydrothermal discharge zone in the Norita rhyolite. The sulphide lenses are of two main types: channel-fill deposits such as the Main Zone and Main Zone West, composed of intricately layered pyrite-sphalerite-chert, which formed by the dynamic down-slope transport and re-deposition of sulphide exhaled from the vent zone; and stratiform lenses such as the Cu-rich A-Zone and A-Zone West, which formed even farther down-slope, in basinal depressions flanking the dome. Although rotated into a vertical position by folding, the sulphide lenses are otherwise essentially undeformed and contain a wide range of preserved primary sedimentary structures.Of prime importance in exploration has been the recognition that the formation of the distal sulphide lenses was controlled by submarine paleotopography, and that it is possible to approximate the sea-floor paleotopography using variations in the thickness and strike extent of the interbedded volcanic rocks. This has proved to be a major and successful exploration tool in the search for further sulphide mineralization in the mine, and offers prospects for use elsewhere in the district."

Jan 1, 1981

By A. Trusiak

"Increasing energy costs in mineral processing is making it necessary for tighter controls over various parts of the concentrating process. Continuous monitoring and control of critical process streams can be easily performed by today's many computer systems. Indeed, the list of successful applications of computers to grinding and flotation control continues to grow. The day is rapidly approaching when the use of computers within concentrators for either process control or simply metallurgical accounting will no longer be a luxury, but a necessity. The benefits from such applications far out weight the initial investment.This paper describes the current application of a process control system at Brunswick Mining in north-eastern New Brunswick. Emphasis is placed on the control of a CuPb flotation circuit, and the benefits derived-from this control.No. 12 Cu-Pb Flotation: The complex nature of the Brunswick flotation process has been described else-where. 1,2,3 Four final concentrates are eventually produced, these being a Zn concentrate assaying 53% Zn, a 30% Pb concentrate, a 20% Cu concentrate, and a bulk Pb Zn concentrate assaying 35% Zn and 17% Pb. The Cu concentate, Pb concentrate, and bulk Pb Zn concentrate are all derived from a primary CuPb concentrate assaying 26% Pb, 11% Zn and 1.8% Cu.The No. 12 CuPb circuit produces approximately two thirds of the total primary CuPb concentrate. No. 12 ore, assaying 3.5% Pb, 9% Zn, 0.25% Cu and 100 g/tne silver, is ground in two parallel grinding circuits. Each line uses a 3.2 x 4.2 meter rod mill in closed circuit with two parallel 3.2 x 3.9 meter ball mills. Ball mill and rod mill discharges are classified in two stages of cycloning. The secondary cyclone overflow, or flotation feed, is controlled at 65% passing 37 microns."

Jan 1, 1981

By B. D. Pandey, D. Bagchi, Premchand

During the separation and recovery of metals from the ammoniacal leach liquor of Indian Ocean nodules by solvent extraction-electrowinning (SX-EW) in close-loop operation, the copper electrolyte containing ~40g/L Cu, 20 g/L Ni and 180 g/L sulphuric acid is bled-off to control the impurities. The recovery of copper and nickel as powders has been examined from the copper bleed solution following partial decopperisation, crystallization of mixed sulphate of the two metals and aqueous hydrogen reduction. From the dissolved sulphate solution containing 17.68 g/L Cu, 18.83 g/L Ni and 0.03 g/L Fe, the copper powder was precipitated at initial hydrogen pressure of 26 bar in an autoclave in 90 min at 140 °C. The residual copper from the spent solution was removed as sulphide and nickel powder was then recovered (99%) in two stages from a solution of pH 4.5 at 40 bar pressure and 190 °C. However, 98% nickel recovery in one stage was achieved when hydrogen reduction was carried out from an ammoniacal solution in the pH range 9-11. Copper and nickel powders were produced from the bleed solution with acceptable purity and specifications suitable for P/M applications.

Jan 1, 2004

By N. Dahata

Earlier research has indicated that an addition of titanium master alloy to aluminum alloys, results in improved fillability, grain refinement and finer pores. B206 alloy differs from other alloys used in automotive industry, with lower titanium level. This paper examines the effect of alloy chemistry (copper and titanium levels) and grain refinement (A1-5`)oTi- 1%B grain refiner) on grain size, microstructure and microporosity in B206 aluminum alloy. In this study, characterization of grain size, microstructure and microporosity was carried out using light optical microscopy (LOM) and scanning electron microscopy (SEM). Results have shown that the addition of 0.05 wt % titanium resulted in grain refinement of B206 alloy. With an increase in titanium to 0.25 wt further grain refinement, much reduced pore size and uniform distribution of pores resulted. These results suggest that B206 with proper addition of titanium has a promise as an alloy for automotive casting.

Jan 1, 2007

By Rodolfo Zanella

Au/TiO2 catalysts prepared by deposition-precipitation with NaOH (DPN) (~3 wt%) and urea (DPU) (~8 wt%) were tested in crotonaldehyde hydrogenation at atmospheric pressure. There is no differences in activity (mole.gAu -1 s-1) and selectivity between both DPU and DPN samples for a given activation treatment. This is due to the fact that DPU and DPN samples exhibit similar gold particle size distribution, although the gold loading in DPU is much higher that in DPN. The DPU samples were reduced under H2 at different temperatures (120-500 °C) or under air at 300 °C with various flow rates, to vary the average particle size within a large range, 1.7 to 8.7 nm. The selectivity to crotyl alcohol (selective hydrogenation of the carbonyl bond) is high, 60-70 %, and almost constant as a function of the particle size. The selectivity to crotyl alcohol is also constant for conversions between 10 and 50%. These results suggest that the adsorption mode of crotonaldehyde is of ?3 or ?4-type. In contrast, the TOF depends on the gold particle size, it drastically increases when the gold particle size is ~2 nm. Our results are in agreement with former studies that suggest that the gold atoms involved in the hydrogenation process are those of low coordination.

Oct 1, 2003

By J. Pepin

When using alternating current submerged arc welding (SAW) to produce pipes from microalloyed linepipe steels, it is critical to balance penetration depth and deposition rates, in order to minimize the number of weld passes while still maintaining good heat affected zone (HAZ) microstructures and properties. A series of bead-on-plate (BOP) submerged arc welds were performed on X70 steel, using different waveform variable settings (i.e., balance, offset and frequency). Weld bead cross-section profile deposition and penetration areas were measured, and both Vickers hardness and Charpy V-notch impact testing were performed. Both single electrode and tandem electrode welds were evaluated.

Jan 1, 2011

By P. O. Parfitt

The Critical Path Method has proved its usefulness at Mcintyre Porcupine Mines Ltd. This paper illustrates the techniques of network construction and analysis, and the application of the method at the Mcintyre copper mine to various projects in the gold mine. C.P.M.'s use in a mill maintenance project is also discussed.

Jan 1, 1966

By J. C. Murray

Introductory: In dealing with a topic so large, one that involves such a multiplicity of details, and that also has certain controversial aspects, it is quite impracticable within the limits of this article to touch upon many most interesting phases and incidents. Also, to bring out the actual truth, it is necessary to make certain categorical statements. The writer believes that all such statements made here-under are supported by facts. Again, however, it is out of the question to cite all the proof. The writer, therefore, will gladly answer any pertinent criticisms or questions and thus supplement the unavoidable brevity of this paper. Controversial points will take care of themselves. Historical: For present purposes the history of gold mining in Nova Scotia may best be summed up in a very few paragraphs, in some of which the writer quotes freely from recent reports compiled by himself. The first material discovery of gold was made in the year 1860. As this and rapidly succeeding discoveries were looked upon as bonanzas, the claims were fixed at a size of 20 by 50 feet, and a yearly rental of $20 was charged. Later the claims (areas) were increased in size to 50 by 150 feet. In the year 1866 a temporarily successful company, so we are informed by a contemporary writer, owned a mill and mining plant worth $6,000. As this fact is cited with admiration, it is apparent that most of the mining and milling must have been done in a very primitive manner indeed.

Jan 1, 1926

By Gyeonghye Moon, Inhyeok Choi, Jyothi Rajesh Kumar, Jin-Young Lee

"This paper deals with the recovery of the tungsten and vanadium from spent SCR catalyst leach liquors by different hydrometallurgical methods. The first part consists of pressure leaching of spent SCR catalyst using caustic soda followed by metal recovery by liquid-liquid extraction. In a leaching process, the following experimental parameters were tested and optimized: NaOH, particle size of feedstock, temperature, and solid to liquid ratio. The optimum condition for leaching of tungsten and vanadium was under the following conditions: NaOH 3 mol/L, temperature 250°C, particle size <300 µm, and solid to liquid ratio 0.4. From these optimum conditions in this experiment, the dissolution efficiency of vanadium and tungsten was 91.5and 87%, respectively. Liquid-liquid extraction following commercial extractants were tested: TBP, Cyanex 272, D2EHPA, Aliquat 336, Primeme JM-T, Alamine 308, Alamine 304-1, and methyl-tri-octyl-ammonium chloride. The conditions for both valuable metal recoveries were optimized.INTRODUCTIONSelective Catalytic Reduction (SCR) catalyst has become the most effective to reduce nitrogen oxide (NOx) emissions from stationary segments such as power plants and waste incinerations around the world due to the reinforcing regulatory trend and emerging environmental issues (Forzatti, 2001; Spivey, 2002; Li et al., 2011).Currently, the most widely used SCR catalyst is V2O5-WO3/TiO2 system due to its great catalytic properties (Li et al., 2011; Marshneva et al., 1995; Marbergeret al., 2015). In general, the composition of the SCR catalyst used in the stationary application is 0.5 to 1 wt% of V2O5and 7 to 10 wt% of WO3(Marberger et al., 2015; Chen &Yang, 1992, Vuurman et al., 1991; Alemany et al., 1991). Currently spent SCR catalysts are treated as waste and disposed of in landfills. This causes a lot of waste of secondary resources of vanadium and tungsten. In terms of industrial value of vanadium and tungsten (Gupta &Mukherjee, 1990; Moskalyk &Alfantazi, 2003) and reduction of pollutant emissions, it should not be disregarded for their recovery for their material recycling from spent SCR catalyst. However, investigations for recovery of metal values from spent SCR catalyst has been rarely carried out."

Jan 1, 2017

By Tassos Grammatikopoulos

The St. Lawrence deposit is a large wollastonite skarn (ca. 9 Mt @ 41.3% wollastonite) adjoining the gabbroic-to-syenitic Leo Lake pluton in the granulite facies of the Frontenac Terrane of the Grenvillian Central Metasedimentary Belt. It occurs within a horseshoe-shaped horizon of quartzite, open to the east. The skarn extends over 1.2 km2, and comprises wollastonite-dominant, wollastonite-clinopyroxene, and diverse quartz-feldspar-sulphide (-titanite) layers, interbanded with, and strongly folded within, the quartzite. As in the world-class wollastonite deposits of the Willsboro district, New York State, no carbonate protolith is preserved and calcite is a negligible constituent of the mineralized zones. Wollastonite development is nonetheless ascribed to metasomatism of a metacarbonate unit by magmatogene, silica-rich, CO2-poor (XCO2 < 0.05) fluids, at P = 350 MPa and ca. 560 oC, or, alternatively, 550 MPa and ca. 630 oC. Several high grade zones, averaging >40%, but locally exceeding 80%, of translucent, white, tabular wollastonite grains, with lengths of 0.2 - 2 cm, have been delimited by drilling. Preliminary beneficiation studies yield high aspect-ratio and high-purity (low Fe and Mn) concentrates. St. Lawrence compares favourably to other known prospects and operating wollastonite deposits; having good chemical and physical properties, low iron content, and high aspect ratios (>20:1). In addition, the deposit has a favourable size and location, and will benefit from a low Canadian dollar. Canada currently has no wollastonite production.

May 1, 2002

By Seshadri Seetharaman, Nurni N. Viswanathan, Haijuan Wang

The present work aims at some process modifications in specified metallurgical processes, wherein CO2 can be used successfully as an oxidant for decarburization in steelmaking and applied in some non-ferrous metals production processes. During the decarburization of Cr-containing high alloyed steels, the present researchers investigated the possible use of CO2 instead of Ar-O2 mixture and could successfully decarburize the steel melt without significant loss of alloyed Cr to the slag phase. A mathematical model was developed based on the bubble formation accompanying the chemical reaction: C(molten steel)+ CO2(gas)= 2 CO(gas). The model predictions were tested by laboratory scale (1 kg) experiments carried out in an induction furnace and very good agreement between the model predictions and experimental results were observed. A national project has been sanctioned in China for the implementation of CO2 in decarburization of ferroalloys as well enable the addition of pig iron in the electric arc furnace process when the scrap supply is limited. New processes have been developed for the utilization of CO2 in the case of non-ferrous processes. A novel method of treatment of Al dross by leaching with water and capturing the evolved NH3(formed by the hydrolysis of AlN) has shown very promising results.

Jan 1, 2015

By Paul W. Kingston

In New Brunswick, during the 1970&apos;s, rocks of the Lower Carboniferous Windsor Group in the Moncton Basin of the Fundy Epieugeosyncline have been the target of intense exploration and drilling programs. Sylvinite ore was discovered in three structural basins of the Moncton Basin near Sussex through a drilling program sponsored jointly by the Federal Department of Regional Economic Expansion and the New Brunswick Department of Natural Resources. In 1973, exploration and development rights to the western end of the Moncton Basin were awarded to the Potash Company of America. One high-grade sylvinite unit, varying between 15 and 70feet in true thickness, with a strike length in excess of 5 miles, is located near the stratigraphic top of the assymetric, semi-diapiric, locally overturned anticline. Late in 1975, exploration and development rights to the Marchbank Syncline were awarded to International Minerals and Chemical Corporation (Canada) Limited. To date, a stratigraphic evaporite sequence, forming the semi-diapiric core of the syncline, has been shown to contain one major high-grade sylvinite unit averaging 70 feet in true thickness over a strike length in excess of 2 miles. Both properties appear to have potential considerably in excess of that revealed by the exploratory drilling, and both, because of numerous mineralogical, structural and stratigraphic similarities, are thought to be depositionally contemporaneous. Both potash deposits lie within 50 miles of the Saint John all-weather deepwater port, thus affording easy access to eastern and mid-western U.S. markets. Further opportunities for potash exploration in New Brunswick are considered excellent, as there are large untested areas with favourable geology and known potassium water anomalies and negative gravity anomalies occurring in the Moncton and Cumberland basins, and in the Central Basin of New Brunswick.

Jan 1, 1979