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By Magella Pelletier

"IntroductionDepuis une vingtaine d'année, les nombreux travaux de géochimie effectués par l'industrie privée et les milieux gouvemementaux ont permis:• de découvrir de nombreuses zones minéralisées a valeur économique;• d'identifier et de vérifier certains patrons de dispersion géochimique au-dessu s de secteurs minéralises déjà connus;• de favoriser le développernent des techniques analytiques;• de forcer le développement d'une mise en carte des résultats d'analyse, qui soit plus adéquat afin de permettre une meilleure interprétation géochimique.L'une de ces cartes géochimiques qui permet le mieux de mettre en valeur les données analytiques et qui fut instaurée au debut des années 80, est la carte d'interprétation géochimique par pondération.Cette carte numérique semi-quantitative, qui est construite à partir des données de base et de l'importance des éléments indicateurs pour une substance donnée, permet d'identifier et de définir des zones possédants de fortes probabilités pour la recherché de sources minéralisées."

Jan 1, 1987

By V. I. Ryaboy, V. P. Kretov, I. V. Ryaboy

Attachment of collectors containing thioamide groups to sulfide minerals is interpreted as interaction between NH-acids and sulfides acting as solid bases with the formation of a donor–acceptor reagent–mineral bond. As the acid function of the reagents increases, their sorption optimum is observed to shift to a less alkaline region. The developed concept has enabled us to propose a method for calculating optimal pH values for the sorption of reagents on mineral surfaces depending on the acidity of the reagents and the pH value of the medium. Our estimates correlate well with the experimental data. We studied the spectra of the reagents containing thioamide groups and the spectra of copper salts and their surface compounds on an oxidised copper film, chalcopyrite, and pyrite using the infrared (IR) spectroscopy. Some effective applications are described of reagents containing thioamide groups in the flotation of copper, copper-molybdenum, and gold ores, both separately and in combination with other collectors. It is shown that the flotation performance is maximised by adding two- and three-component collector combinations, including collectors containing thioamide groups. In this case, the increase in the recovery of copper, molybdenum, and gold is up to 2-5% compared to conventional process conditions. A new, high-performing reagent containing a thioamide group is proposed. A commercial pilot batch of the reagent was produced and sent for flotation tests in gold ore applications. Keywords: Thioamide reagents, dialkyldithiophosphate, collectors, flotation, arsenopyrite, chalcopyrite

Jan 1, 2020

By M Sciortino, J Korczak, J Muinonen, A St-Jean

The Dumont deposit is a large (1179 Mt reserve), low-grade (0.27 per cent nickel) nickel sulfide project located in the Abitibi region 25 km west of Amos, Quebec. Royal Nickel Corporation (RNC) acquired the project in 2007 and has since taken the deposit through to feasibility. The disseminated nickel sulfide and alloy mineralisation is hosted within the serpentinised dunite subzone of the Dumont Sill; a differentiated, pervasively serpentinised, ultramafic sill of komatiitic affinity. Pentlandite ((Ni,Fe)9S8), heazlewoodite (Ni3S2) and awaruite (Ni2.5Fe) are the dominant nickel-bearing metallic phases and can be recovered by conventional methods (flotation, magnetic separation). Non-recoverable nickel is also present within serpentine and olivine of the silicate matrix.A detailed mineralogical program including 1420 QEMSCAN« samples and 4400 electron microprobe points was undertaken to increase the understanding of the nickel deportment in the various recoverable and non-recoverable phases in a spatial context across the deposit. A total of 105 metallurgical tests have been performed under a standard procedure which have linked the mineralogy to metallurgical performance. This has allowed the creation and modelling of geometallurgical domains on a block-by-block basis to understand the recovery variation and metallurgical performance throughout the deposit. Understanding the spatial variability of Ni deportment in recoverable and non-recoverable phases through mineralogy is the key to understanding metallurgical performance, thus unlocking the value of the Dumont deposit and other large tonnage low-grade ultramafic nickel deposits.CITATION:Sciortino, M, Muinonen, J, Korczak, J and St-Jean, A, 2013. Geometallurgical modelling of the Dumont Deposit, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 93-100 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By K. Noda

Tamano Smelter of Hibi Kyodo Smelting Co., Ltd. is carrying out a low cost production using a Tamano Type Flash Smelting Furnace (T-FSF), which is an improved version of Outokumpu Type Flash Smelting Furnace but without slag cleaning furnace and also by developing its own coke combustion technology. Coke combustion technology that is the basis of the system has been improved several times and, at present, it has evolved to a stage where it can be reproduced on the Computer guided system for Coke Combustion in the T-FSF (CCCT) using a general- purpose computer. This CCCT is featured by 'its trend control and predicting function, and an operator can freely control the operation parameters so as to control the operation flexibly. We have recently developed an overall energy reduction system covering the Smelting Plant to Sulfuric Acid Plant, which we call an Optimum Low Cost Operation System (OLCO) to reconsider the energy costs including coke, heavy fuel oil, and electric power. In this report, we would like to present the recent operation of T-FSF based on CCCT as well as the optimum energy operation utilizing OLCO system.

Jan 1, 2002

By J. Dubbert, T. H. Jones

"This paper describes a rib-control methodology that uses standing support to provide most of the lateral resistance to the rib. The method is analyzed, and its boundary conditions for rib control are described. In this method, an animal-fencing mesh product covers 80 percent of the rib surface and is sparsely bolted to the rib. Can supports or other similar stiff supports are installed primarily as roof support for the entry. As the rib spalls and dilates, the mesh catches the material and expands, pressing against the standing support. Mining proceeds, and vertical roof loads increase the normal force on the Can supports, causing friction at the top and bottom of the support to go up, thereby improving lateral resistance to rib swelling.At one mine in the western United States, this method has proved excellent at preventing the buildup of rib spall. It substantially reduces the number of bolts used for screen installation, improves installation efficiency, reduces manual labor and provides more rib coverage than many screening methods. Because standing support is typically part of the roof-control plan in longwall tailgates, no additional standing-support costs are incurred. IntroductionRib safety in underground coal mines is an oft-studied topic because ribs are high-hazard areas. An overview of early rib safety research can be found in Jones and Mohammed (2014). There is a significant difference between rib support and rib control. Support improves safety through the installation of strengthening elements, such as bolts and dowels, designed to reduce rib spalling. Although spall reduction is preferred, controlling how the rib fails is enough to ensure safety in some situations. Rib control uses external elements to provide confinement, thereby holding sloughed material in place, or to prevent falling rib material from striking mine personnel. This paper presents a study of a control method used on the pillar side of a longwall coal mine tailgate in the western United States."

Jan 1, 2015

By G. L. Oldright

"The various districts in the United States where complex lead-zinc ores occur are too well known to require description, there being hardly a mining State with any large amount of ores of either metal that is free from this problem. This paper briefly presents developments in the volatilization process, as applied to the treatment of such ores, since the data in Bureau of Mines Bulletin 211** were published. In that bulletin, among the many types of ore treated, examples are given of the treatment of lead-zinc ores by the chloride volatilization process for the separation of lead. An outline of the general process, with views of the rotary kiln, ore feeder, firing system (these three features resemble closely those of cement-kiln practice), dust chambers, and a Cottrell precipitator to remove the fume from the gas, are also shown in that bulletin, to which the reader is referred for the results obtained, and for practical details of operation. The small initial cost of a volatilization plant, and its adaptability for use in isolated districts were emphasized.In general, it was found that when an intensely oxidizing atmosphere was maintained in the furnace, a good lead-zinc separation could be made. Therefore, a heavy sulphide ore would have to be preroasted, and enough air would have to be admitted to obtain complete combustion of whatever fuel might be used.The work done by private companies and the bureau since the data for Bulletin 211 were obtained, indicates that the ores most immediately amenable to treatment by volatilization are of two types. The first is an oxidzed lead. silrer ore whose variable lime content makes it impractical to chloridize the ore for acidulated brine leaching, and whose base metal content makes treatment by cyanidattion unfeasible, The second type is the lead-zinc ore mentioned above, and is the one on which data are available for publication at present. This article Chows what ores of this latter type are amenable to treatment by volatilization, by giving briefly some of the more important physical and chemical properties an ore should preferably possess. Several examples are given from both laboratory experimental work, and from practice in the field, showing various phases of the volatilization process."

Nov 1, 1923

An important problem in mine operations is the classification of material as waste, low-grade stockpile, and ore. This classification must often be made with blasthole data that are widely spaced and that have sampling errors. Geo-statistical simulation techniques combined with basic economic principles allows a procedure for classification that maximizes expected profit. Geostatistical simulation methods (Gaussian, indicator, or annealing-based) allow the integration of hard and soft data in the creation of alternative, equally-probable, realizations of the mineral grade(s). At each location, for each realization, we calculate the "profit" if the block were to be classified as ore or waste The optimal classification is the one that maximizes expected profit (a Maximum Profit Se-lection (MPS) procedure). We discuss the theoretical justification of the method and implementation details. The use of blasthole data from different types of mineral deposits, that is, different levels of continuity, is considered. We also show the efficacy of the procedure with different levels of sampling error. The increased revenue due to the MPS procedure and improved sampling is shown. We show the geostatistical simulation procedure and the uncertainty in block grades that result from incomplete and imperfect sampling. The optimal classification is presented. Optimal block classifications are transferred to realizable dig-limits by hand-drawing polygonal boundaries. We compare the results of the proposed method to classification based on kriging. Limitations and areas of future work are identified.

Jan 1, 1999

By Albert L. Toenges

The production of coal from underground mines in Washington declined during the recent war owing to shortage of manpower, and coal was shipped to the Pacific Northwest from mines in the Rocky Mountain region. The movement of this coal into Washington required the use of railroad equipment that otherwise could have been used for transporting war materiel and personnel. Strip mining uses a minimum of manpower, and the development of coal areas in the Pacific Northwest that can be mined by the strip method should increase production in the area, thus releasing railroad equipment from the necessity of transporting coal long distances and also providing consumers with a lower-cost product. The development of a strip mine to supply the demand at low cost requires a large investment in heavy equipment. In order that the fixed charges due to large investment in plant and equipment may be kept at a minimum, large reserves of coal must be proved. A reconnaissance of an area near Toledo, Lewis County, Wash., indicated a large bed of lignite that could be mined by strip methods. The area is approximately midway between Portland, Oreg., and Tacoma, Wash. (refer to fig. 1), and the opening of a large mine in the area would supply fuel to these and other nearby centers.

Jan 1, 1947

By John M. Hird

Texas Gulf Sulphur Company's Lee Creek Mine has opened a major phosphate mining district in the Central Coastal Plains of North Carolina (Fig. 1). The ore deposit as it is now known was roughly outlined in 1961 by a Texas Gulf geologist using wire line exploration methods. Slightly uraniferous phosphate materials were detected by a slim-hole gamma ray probe run in numerous farmers' water wells penetrating the formations. A follow-up-core drilling pro- gram determined the economic ore limits to lie in the south central section of Beaufort County beneath 70 feet to 120 feet of unconsolidated sediments. The 50,000 acre deposit is known to contain over two billion tons of phosphate ore amenable to strip mining methods. A part of the deposit underlies several thousand acres of the Pamlico River estuary. The 90 million dollar capital investment plant built by Texas Gulf during 1965-66 included a strip mining operation using a 72-yard walking dragline, a three million product ton per year flotation concentrator, four fluid bed calciners, a sulphuric acid plant (acid for captive use), a phosphoric acid plant, and three solid fertilizer material plants. Shipment to domestic markets is by rail and truck and to over- seas markets by barge to a transshipment terminal at Morehead City, North Carolina. Early mining investigations were conclusive first that the phosphate ore could economically be recovered only by dry strip mining methods, and second that artesian ground waters in the formation (Castle Hayne limestone) underlying the ore would have to be controlled. This report will relate the application of ground water hydrology in depressurizing the Castle Hayne aquifer to facilitate dry strip mining at depths 130 feet below sea level at the Lee Creek Mine.

Jan 1, 1970

By Wang Yingmin, Xu Zhuyun

The optimum of general mine ventilation networks is very difficult and has a considerable significance. Based on the content model, this paper presents a more general nonlinear programming model whose number of variables equals that of independent meshes. The constrained conditions are linear inequalities only. The model is changed into an unconstrained problem with multiper method. The optimum results are computed with DFP algorithm and the Improved Golden section method is used in its linear searching. The computer program written in Quick BASIC is suitable to the optimum of any type of large mine ventilation networks with different regulating devices. The paper presents two examples for optimum of ventilation networks.

Jan 1, 1991

By Kenneth C. G. Heath

The paper point out the economics importance of the Torco process as lubricant and fuels of the motor in the mining. It is possible to envisage an arrangement in which TORCO would be used to treat a sulphide ore, the acid used to dissolve the metallic ccoper in the concentrate and the copper produced in cathode form by electrowinning. However, there are studies point out that it would be as profitable as conventional flotation, smelting and refining. To carry out full testing of the TORCO process on anyore would be expensive, involving sending several hundred tons to one of the pilot plants located in Johann esburg or Milan. Such pilot plant testing should & be considered as confirmatory rather than exploratory, and a good economic case for using theTORCO process would have to be made out based of mallet scale testing before in curring the larger expense.

Nov 20, 1969

By F. Q. Su

Underground Coal Gasification (UCG) is a promising environmentally acceptable clean-coal technology. A typical UCG system has two wells drilled from the surface into a coal seam with some separation of injection from production. The wells are connected underground by various linking techniques. After creating a combustion reactor in an underground coal seam, air and oxygen flow through the injection well. Heat energy and gases are collected from the production well. As gasification progresses, the combustion reactor is moved along the linking hole. Using this process, the fracturing activity inside the coal seam serves an important role for enlargement of the gasification zone because the surface area oxidization increases continuously by coal cracking. For effective coal gasification, fracturing activity must be controlled. Moreover, excess fractures inside the coal seam and surrounding rock can induce gas leakage, underground water contamination, subsidence, etc. Therefore, monitoring and control of fracturing activity in underground areas constitute key technologies for efficient and safe UCG. To monitor fracturing activity, we conducted laboratory and small-scale field experiments of UCG using acoustic emission (AE) measurements. UCG model tests were conducted for linking and coaxial types UCG models. Coaxial UCG systems are compact and are anticipated for application in underground coal seams having a complex geological structure. The UCG model consists of a coal block molded in a steel canister (20 liter capacity) with heat-resistant mortar, with a linking hole or a coaxial-hole passing through the coal block. During coal combustion, coal temperatures, production gas contents, and AE activity were monitored under the control of injection-air and oxygen flow rates. Results show that the combustion propagated inside the specimen along the linking hole. Many AE events were generated during coal combustion. The AE activity was related closely to temperature changes inside the coal block. This AE generation apparently results from crack initiation and extension around the coal combustion area under the influence of thermal stress. However, comparing the results from UCG models of linking and coaxial types, the gasification of the linking type model showed an average calorific value as high as 11.3 MJ/m3. The coaxial type yielded an average calorific value of produced gas as only 5.79 MJ/m3. In the coaxial type of UCG model, the combustion region was limited to the area around the coaxial hole. The AE activity was lower than in the linking type model. For small-scale UCG field experiments, linking and coaxial types were tested at an open pit coal mine in Hokkaido, Japan. Using a linking type UCG, 58.2 kg coal was processed in 39 h, with the calorific value estimated as 11 MJ/m3. However, the coaxial type UCG processed 7.0 kg coal in 9 h, yielding an estimated calorific value of 6.0 MJ/m3. These tendencies resemble those of results of laboratory UCG experiments. Results of these experiments demonstrate that AE monitoring is a useful tool to evaluate combustion reactors for efficient and safe UCG systems. To develop a coaxial UCG system, results show that fracture control around combustion reactors is indispensable.

Aug 1, 2013

By Virgil J. Stachura

The Bureau of Mines conducted a series of delayed blasting experiments at a West Virginia contour coal mine that resulted in smoother highwalls. The 17; were smoother due to reduced overbreak and inherently safer A, to reduced likelihood of rockfall. Reduced overbreak was accomplished by an increase in the highwall hole delays, which changed the effective delay pattern geometry and the direction of burden movement. The blast delays in the highwall holes were 50 to 100 ms longer than the mine's nominal design pattern (flat V, 17- by 42-ms surface delays, 200-ms in-the-hole delay). The burden movement was effectively changed from a 45* angle to 90* with respect to the highwall. The results of the blast delay changes were evaluated using terrestrial photogrammetry to generate vertical profiles at regular intervals. This evaluation showed that delay changes produced generally smoother vertical profiles.

Jan 1, 1984

By Noel N. Moebs

The coal wants at the Westland Mine in southwestern Pennsylvania consist chiefly of elongated, sandstone-filled channels with slickensided basal contacts. Tentatively identified as washouts, these channels are about 1,000 feet long and 300 feet wide, are erratic in occurrence and trend, and are difficult to delineate from the customary core drilling pattern. Roof conditions are hazardous adjacent to the washout contact, but roof stability is generally unaffected greater than 30 feet away.

Jan 1, 1981

By BARBOSA AMILTON, Denise C. R. Espinosa, David B. Dreisinger

Chelating resins can be used to recover important metals from different sources, and it is important to understand which resin is most suitable for each metal [1]. This review  benefits the mining industry because chelating resins can be used to recover metals from low-grade ores and mining tailings, increasing the industrial process efficiency [2–4]. Furthermore, the use of chelating resins in mining processes and mining tailings has the common problem of metals contamination, with iron being the main contaminant in low-grade ores and tailings. Understanding how contaminants decrease ion exchange efficiency is significant for industries [5

By A. Atta-Quayson

Since 2012, Ghana has been implementing local procurement regulations in the mining sector to broaden and deepen linkages between mining and other sectors of the economy. The regulations have been implemented in collaboration with the mining industry. This paper offers an in-depth analysis of how the local procurement regulations and related initiatives have been implemented so far. Primary data gathered with semi-structured interviews and secondary sources of data indicate a steady improvement in both in-country procurement and local manufacturing of inputs for the mining industry. There are, however, some challenges relating to tariff structure and support (financial and technical) for local suppliers and manufacturers to meet high standards and demands of the mining industry. This calls for a well-thought-out strategy and programme of activities to sustain and improve on progress made.

Feb 2, 2022

By Marcos Valdéz Córdova

El presente estudio señala el proceso de mineralización en el domo de Yauli a través de una revisión en el comportamiento de dominios estratigráficos, estructurales, intrusivos, metamórficos y distintos minerales de alteración hidrotermal. Asimismo se describe la geología, su estructura, la alteración de los intrusivos, la alteración de los silicatos metamórficos, la alteración de los mármoles y calizas dolimíticas, cuerpos, mantos y las vetas de reemplazamiento.

Nov 20, 1978

By B. B. Gottsberger

IT SEEMS strange that so many years after the pas¬sage of the first acts requiring registration or licensing of engineers, so few members of the mining branch of the profession are aware of what has taken place. Laws regulating the practice of engineering have now been passed in 19 states of this country, and in many others, such legislation has been proposed. That such laws are necessary for the protection of life, health and property, as is stated in most of them, is doubted by many. That the standing of the engineering profession will be improved by them is certainlyy open to question. That such laws are a welcome addition to the regulation of business by governmental agency, is not likely to be a general opinion. That once more, and in spite of appeals to engineers to interest themselves in affairs of government, an active minority has succeeded in imposing its will on a passive majority, seems but too true. However, the laws are there and information regarding them should be of use and interest to those most directly concerned.

Jan 1, 1921

By James R. Craig

The General Image Processing System (GIPSY) is being employed for the quantitative textural analysis of complex sulfide ores from the Southern and Central Appalachians and for the determination of liberation characteristics of the mineral constituents during grinding. Optical images from a microscope-mounted TV camera or from 35mm film are converted into digital images which are subsequently analyzed by GIPSY, a transportable image processing software package. Properties measured by GIPSY include spatial distribution of mineral constituents, grain sizes, grain shapes, grain orientation and mineral co-occurrences.

Jan 1, 1982

By B. K. Gorain

Barrick' s Buzwagi copper-gold deposit in Tanzania comprises oxide, saprock and sulphide mineralized zones averaging approximately 0.058oz/t gold, 0.13% total copper and 0.03% cyanide-soluble copper. A comparative evaluation of the project based on two potential flowsheet alternatives is presented. The first flowsheet included a gravityconcentration and carbon-in-leach (CIL) plant. The second flowsheet was based on a Gravity-Flotation-CIL plant, which proved to be more economically robust. Selective flotation of copper minerals to produce a saleable copper concentrate proved to be challenging. Detailed characterization of the Buzwagi deposit was carried out through understanding of ore mineralogy, mineral liberation, floatability and selectivity, reagent chemistry and regrinding issues. With this insight, a flotation concentrate of greater than 25% Cu was achieved, recovering a significant amount of copper minerals and tellurides. The overall economics of the project improved significantly with the addition of flotation. Leach tests on gravity and flotation tailings showed an overall increase in gold recovery of approximately 6% for a Gravity-Flotation-CIL plant compared to that for a Gravity-CIL plant.

Jan 1, 2007