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By Michel Gauthier, Pierre Marcoux, Gaétan Morin

"The recent opening of Muscocho's gold mine at Montauban, as weil as the discovery of several new copper-gold showings of a similar nature near the confluence of the Saguenay and St , Lawrence has revealed the existence of a new metallogenic gold province which is located within supercrustal units of Helikian age within the Grenville Province. Three metalliferous belts have been identified, each one of which is related to a series of SW-NE trending faults. The first is located in southeastern Ontario and southwestern Quebec. The second extends from the Balmat-Pierrepont mining district of New York State up to the Lac St. Jean region of Quebec, and includes the Montauban camp. The third follows the St. Lawrence river in Charlevoix County and along the north shore of the Gulf of St. Lawrence.The gold mineralization which is present in the central portion of the Grenville Province is of two types: either stratiform or vein. Deposits of the first type, of which the Muscocho is the type locality, are economically the more interesting of the two. Not only is this mineralization stratiform, but also shows a distinct affinity to AI-rich, Mg-rich or calc-silicate-rich bands. As is the case with the Bousquet and Hemlo regions of the Superior Province, they are associated with layers which are rich in sillimanite and occasionally staurolite. A second parallel between the Bousquet and Montauban deposits might be the presence of manganesian gamets, which have been recognized at the two localities. Some of the mineralization in the central Grenville Province is located within thin bands of iron formation which are rich in arsenic.The stratiform gold deposits of the central Grenville Province are of exhalative origin and are located within a volcano-sedimentary terrane. It is probable that a part of the gold present in these Helikian deposits have been derived by remobilization of Archean mineralization. The vein showings form as a consequence of the remobilization of the Helikian strata during the Grenville metamorphism,"

Jan 1, 1985

By F. Q. Cheng

Despite the successful industrial practice to recovery KCl by flotation, the adsorption state of collectors at KCl salt surfaces is still not fully understood. In this paper, the captive bubble contact angle measurements at KCl and NaCl crystal surfaces in their saturated solutions are reported. The influence of different collectors and their concentration are considered. The results show that both cationic and anionic collectors produce a hydrophobic state at the structure breaking KCl salt sur-face, with finite contact angle values of between 30o and 40o. In contrast, the contact angle at the structure making NaCl salt surface is zero at all collector concentrations, suggesting that no collec-tor adsorption occurs, a supposition that is supported by results from molecular dynamics simulation (MDS). Further, it appears that the presence of surface defects such as edges and corners promote the adsorption of collectors at the KCl surface, and that the flotation is achieved by bubble attachment at the edges/corners of KCl particles with the formation of aeroflocs.

Jan 1, 2014

By F. E. Buch

THE Smelter is designed for a production capacity of 10,000 short tons of blister copper per month, when operating on the present concentrate grade. The Smelter lay-out is shown in Fig I. The major units of equipment comprise two reverberatory furnaces, three 13 by 30 ft Peirce-Smith converters, two straight line casting machines, one being served by a 13 by 30 ft holding furnace and the other by a ladle tilting quadrant, two converter ,aisle cranes and two converter blowers. The plant is compact and the general arrangement of standard gauge railway tracks and conveyor belts provides for a smooth flow of incoming materials and metallurgical products. Concentrate is received by conveyor belts and fluxes in standard railway trucks. The local track system is covered by an electric trolley locomotive. The Smelter treats a wet (10 pct moisture) flotation concentrate containing approximately 53 pct total copper and 0.9 pct oxide copper. The predominating minerals are chalcocite, chalcopyrite and bornite accompanied by small quantities of malachite and cuprite. The gangue is highly siliceous and requires limerock as a flux. Metallurgy would be straightforward were it not for the necessity for eliminating k bismuth which occurs as an impurity in the ore along with the copper. Directly or indirectly most of the Smelter problems can be traced to the necessity for bismuth removal. Copper recovery, based on new copper treated, averages 97.5 pct. GENERAL DESCRIPTION Flotation concentrate, containing to pct moisture, is conveyed from the filter plant to the smelter storage bins by conveyor belts, the material being weighed in transit by a revolving drum type of weigh-hopper manufactured by Samuel Denison and Son, Ltd. The weigher consists of a steel drum with dished ends carried on a horizontal shaft and rotated by an 8 hp squirrel-cage motor through a worm and spur reduction gear. A feed mouth in the drum permits of filling and discharging. The whole unit is supported on a framework resting on weighing levers, which in turn connect to transfer levers, thence to an indicator of the steelyard type situated 16 ft from the centre line of the drum. The indicator is of the "Denison" patent equilibrium controlled ticket stamping type, insuring mistake-proof records by a combination of electrical and mechanical movements which prevent the operator from printing until the cover enclosing the steelyard is closed and until the poise-weights have been set correctly to the weight of the hopper and contents. The machine is capable of weighing 30 short tons at a time but the usual load is 28 tons. After obtaining the gross weight the drum is rotated and discharged into a receiving bin situated below it. The empty drum is weighed and the net weight re-

Jan 1, 1947

By Leming Ou, Longsheng Yi, Qiming Feng, Yiping Lu, Qing Shi, Kun Liu, Guofan Zhang, Yanfei Chen

"Three important components of stirred tanks involved in energy consumption, the impellers and baffles, were investigated to intensify the agitation pretreatment on the flotation of nickel ores. Flotation tests revealed that the stirred tanks with two impellers had an advantage over those with one impeller in intensifying agitation pretreatment, and the higher agitation speed led to better flotation performance of nickel ores. Installation and removal of baffles were also employed in the stirred tanks, and flotation tests demonstrated that with baffles, the flotation grade increased significantly. These agitator design improvements were used to demonstrate that the energy supplied to the system significantly influences the flotation recovery and that if the energy consumption of the agitation pretreatment is ideal, flotation efficiency can be improved. Data from full-scale operations backed up these results.INTRODUCTIONThe flotation recovery of nickel-copper sulphide ore at the Western China nickel mine has historically been difficult due to the presence of large amounts of serpentine minerals (Feng, et al., 2012). Many studies reported that serpentine minerals tend to have a positive potential at pH values up to 9.5, while sulphides (such as pentlandite and chalcopyrite) have a low isoelectric point(Feng, et al., 2012). Serpentine minerals can form surface coatings on negatively charged sulphides surface due to electrostatic attraction when they interact with each other, which may also reduce collector adsorption and increase the hydrophilicity of the sulphide particles. In order to improve the flotation of nickel sulphides, sodium hexametaphosphate, sodium silicate, carboxymethyl cellulose (CMC), and other agents are used to disperse serpentine coating from sulphide surfaces in the flotation of the Jinchuan deposit and other nickel ores in China ( Kirjavainen and Heiskanen, 2007; Lu, et al., 2011). However, it is difficult to improve of the sulphide flotation due to the high dosage and the lack of selectivity."

Jan 1, 2018

By Louis C. Brichta

The Capital Mine is one of, the more important zinc mines in Lawrence County, Mo. Owing to the urgent need for additional zinc during the war and the available facilities for the treatment of zinc-lead ores at the property, the Bureau of Mines examined the mine during July and August 1942 and selected it for further investigation by churn drilling, which was accomplished in the fall of 1943 and spring of 1944. At the conclusion of the drilling on the Capital holdings, the Greenland property, immediately south, was investigated by drilling two additional holes. Results of the investigation are presented in this report.

Jan 1, 1948

By May J. R

Exploration, including research, has fuelled the enormous expansion of the Australian mineral industry in the last three decades. Analysis of success and failure in exploration and research has therefore potentially powerful lessons and messages which may be used to influence the future shape and direction of the mineral industry. Research has been an integral part of organised corporate mineral exploration since its beginnings in Australia in the 1930s. In corporations, the activity generally called project generation or new project development is the main expression of exploration research but mostly it goes unidentified and poorly documented except perhaps when a successful discovery is made and reported on. The competitive nature of exploration means that extended and detailed analysis of corporate exploration research across the industry is impossible to achieve.

Jan 1, 1992

By Dário Freire Arrais

Atualmente, há uma grande preocupação em criar materiais cada vez mais sustentáveis, dentro desse contexto, encontra-se, o compósito de matriz polimérica adicionado de fibra natural. Dentro dessa classe de fibras, uma das mais utilizadas é a fibra de bambu, a qual apresenta um grande desafio devido a dificuldade para a sua obtenção ultrapassando o comprimento crítico de utilização, que é em média 200 mm. Fibras com essa dimensão são consideradas longas, sendo utilizadas principalmente para a confecção de compósitos como carga de reforço dentro da matriz. Logo, é de fundamental importância determinar métodos simples de obtenção das fibras para se obter melhores resultados diante da finalidade do compósito. Esse trabalho visa apresentar de forma clara processos mecânicos e químicos para se obter fibras de bambu curtas, particuladas e longas, apresentando o seu potencial mecânico através de ensaios mecânicos. Ao realizar ensaios químicos e mecânicos, os procedimentos que apresentaram melhores resultados em relação a fibra ensaiada natural foram a mercerização a 5% de NaOH em solução aquosa e acetilação por uma hora a 100ºC.

Aug 16, 2017

By I. E. Odom

The rare magnesium-lithium clay mineral hectorite occurs at many places in the McDermitt caldera of Nevada-Oregon. Commercial development of several high purity deposits began in 1986. The hectorite was precipitated in a lake environment formed after collapse of the McDermitt caldera. Hectorite beds and lenses are associated with volcaniclastic sediments, limestones, dolomites, zeolites and locally sandy bentonites. The high purity deposits appear to be associated with hydrothermal areas. The hectorite consists of extremely small flake-shaped crystals, and Ca is the predominant exchangeable ion. Its color ranges from white to light green. Commercial uses developed to date include high brightness magnesium aluminum silicate products, organophilic clays, pulp retention, and ceramics. The MAS is used as a suspending agent, binder, stabilizer and thixotrope in aqueous solutions for cosmetics, household cleaners, pharmaceuticals and miscellaneous industrial applications. Organoclays are used in printing inks and paints.

Jan 1, 1992

By Fred D. Wright

Some new equipment for drilling vertical holes, cleaning blast holes, hauling explosives, and conditioning Diesel exhaust gas has been developed. at the Bureau's Experimental Oil-Shale mine near Rifle, Colo, The equipment has application, not only in oil-shale mining, but in many of the country's underground mines in which room-and-pillar methods of mining are employed. This report presents the Bureau's experience in testing the following equipment in the Experimental Oil-Shale mine: 1. A four-drill benching jumbo for drilling 23-foot vertical blast holes 2. A jet borehole blower for efficient cleaning of deep, vertical blast holes. 3. An explosives truck equipped with two compartments to provide safe conveyance for dynamite and detonators. 4. A mobile, electric substation to provide switching equipment, low-voltage and overload protection, and transformer facilities to remote locations in the mine. 5. A chemical conditioner for scrubbing the exhaust gases from Diesel-powered equipment used in underground operations. 6. Other units of equipment which have been tested at the Experimental mine.

Jan 1, 1951

By Yujing Jiang, Xuezhen Wu, Bo Li, Tomomi Iura, Gang Wang

"Yielding bolt has been widely used for rock reinforcement in mining and civil engineering in high stress conditions. However, the interaction mechanism of yielding bolt and matrix mass is still not clear at present, and no analytical model is available to predict its reinforcement effect quantitatively. In this paper, the mainstream yielding rock bolts were reviewed firstly. After that, a coupling model is proposed to account for the interaction between yielding bolt and matrix mass. Based on the plane strain axial symmetry assumption and the incremental theory of plasticity, equilibrium equations and compatibility equations of matrix mass, and also the response of yielding rock bolt are deduced theoretically. The proposed method was programmed in Visual Basic development environment, and a semi-analytical solution for the coupling model is achieved. The reinforcement mechanism of yielding bolt in conventional tunnelling is clearly demonstrated through an illustrative case study. The reinforcement effect of yielding bolt is estimated quantitatively, and the distribution of axial force along the bolt is presented. In addition, the validity of proposed method is verified by numerical simulations. INTRODUCTIONHigh stress in surrounding rock mass can cause serious stability problems such as massive squeezing in soft rock and rock burst in hard rock. It is observed that many conventional rock bolts failed when experiencing large displacement, which implies that they are too stiff to sustain large deformation and dynamic conditions (Stillborg, 1994; Hoek et al., 1995). Yielding bolt, which can also be called energy-absorbing bolt, has been widely used for rock reinforcement in mining and civil engineering for these conditions (Neugebauer, E., 2008). This paper focuses on the static reinforcement effects of the yielding bolts with analytical method and numerical simulations."

Jan 1, 2015

By John W. Korczak

The use of geological and grade block models has been standard practice in mine design for many years now, with a wide range of software available for creation and analysis. Although geotechnical parameters are of vital importance to mine planning there is very little in the way of commercially available systems for integrating geotechnical data into the mine planning and design process. Sirovision is a new technology developed by the CSIRO (Commonwealth Scientific and Industrial Research Organization) in Australia for automated, safe and accurate 3D mapping of geological and geotechnical features. Datamine has integrated this capability into its product range so that Sirovision has become an integral part of the day-to-day mapping, mine geology and geological / geotechnical modeling in both open pit and underground mine environments. This is the first integrated underground application of Sirovision from Datamine collaboration with Xstrata Nickel at the Nickel Rim South Project. This paper discusses the role of Sirovision in collecting the raw data required for geological and geotechnical analysis and the interpretation in a quick, safe, auditable and reproducible manner.

May 1, 2009

By Webster S. Anderson

The design, development, and testing of hydraulic props to provide a lightweight, high strength, recoverable unit is described. Modifications in design incorporating threaded components resulted in the development of a lightweight hydraulic prop fabricated from aluminum alloy tubing. This new design facilitates interchange and replacement of component parts, and the physical properties of the material are not changed as they are when welding is required. The new prop is 65,000 pounds and has a maximum load capacity of a lower weight-to-load capacity ratio than the hydraulic props now available.

Jan 1, 1967

By Stephen C. Tadolini, Robert Hawker, Peter Mills, Colin Grubb, Tom Meikle

"In unfavorable strata conditions, it is often necessary to install additional long tendon support as part of a primary support cycle. Although these support systems provide the required additional stability to the roadway installation does have a significant effect on the rate of development. To overcome the slow cure time of Portland cement-type grouts, the use of two component resin systems, such as polyurethanes and urea silicates, have become favorable. However, concerns over low modulus and creep properties has led to the development of a two-component grouting medium that displays the properties of traditional cable grouting materials with the rapid reaction times of pumpable resin systems. This paper describes product testing, application, surface trials, underground trials, and full-scale applications of the Tekthix System in a dynamic underground environment. INTRODUCTION Single-component cement grouts have been used to anchor long tendon supports for many years. They range from high- to low-slump Portland cement and can be slow-setting to fast-setting grouts. However, current cement grouting systems, which includes the grout and equipment, have some disadvantages: 1. Low-slump grouts require pumps that can handle a thick, high-viscosity grout, so choice of pumps is limited. 2. Pumping distance is limited with current cable bolt grout pumps; operators often tend to add water to allow pumping long distance, which adversely impacts the quality and strength of the material. 3. Fast-setting grouts tend to cause issues with pump and line blockages due to the reduced working life of these single-component materials."

Jan 1, 2017

By AIME AIME

THE revised program for the San Francisco meeting, with assignment of the various papers to the several sessions is now available and is printed below : MONDAY, OCT. 7 . General Meeting, 11-12 A.M. Chairmen: Frederick W. Bradley and E. A. Hersam. Opening of the session by the Chairman of the San Francisco Section-E. A. Heraam. Address of welcome by the President of the Institute- Frederick W. Bradley. Address: The Mining problems of the West--Charles W. Merrill.

Jan 1, 1929

By Liu Jie

Refractory iron ore deposits in China have various genesis and complicated types, the nature of which is poor, fine-disseminated and complex. Therefore, refractory iron ore could scarcely be separated and utilized by traditional mineral processing technology at present. It is necessary to explore deep reduction technology to change the characteristics of refractory iron ore and to use effectively the iron resource. And deep reduction technology is that on the condition of higher reduction temperature than that of magnetic roasting and stronger reducing atmosphere, the iron oxides from iron ore was reduced to metallic iron particle that is easy to dissociate. And then production from deep reduction is easily separated by magnetic separation and iron powder production was obtained finally. Deep reduction technology for Lingyang iron ore from Jilin, China, as the refractory iron ore, was studied in this paper. The influences of such main factors as reduction temperature, time and coal content were investigated. The results showed that the Metallization rate of reduction product was up to more than 90% under optimum conditions, and then higher iron grade and recovery of reduction iron powder were obtained from subsequent magnetic separation. Furthermore, the deep reduction mechanism in the system was studied by the means of XRD and SEM analysis for reduction production and Physical Chemistry of Metallurgy. Analytical results indicated that during deep reduction, the size of iron particle from deep reduction materials was increasing as reduction temperature rising and reduction time extending. The growth of metallic iron particle from deep reduction production was divided into such three stages as reduction nucleation, deep reduction and growth of metallic iron particle.

Sep 1, 2012

By L. M. Demers, D. C. Kuhn, N. El-Ayouby, C. F. Stanley

"Oxygenated metabolites of arachidonic acid (MJ are produced by the alveolar macrophage (AM) and have been shown to mediate inflammatory reactions. We therefore assessed the production of eicosanoids by AM harvested from the lungs of rats ex· posed to a bituminous coal dust for 2 wk in an inhalation chamber in order to determine if AA metabolism was altered in a manner that may promote an inflammatory response in the lung. Exposure to coal dust resulted in a 66% increase in the number of AM harvested, an increase in thromboxane A2 (TxA;i) and leukotriene 84 (LTB,j) production to 222% and 181% of control values, respectively, and a decrease in prostaglandin E2 (PGE:i) production to '62% of control values. In AM harvested from rats allowed to breath clean air for 2 wk following coal dust exposure, PGE2 production returned to control levels but TxA2 and LTB4 production remained elevated. The TxA2 synthesis inhibitor UK 38,485 reduced TxA2 production in dust-exposed AM both immediately and 2 wk following exposure. Thus, exposure of rats to coal dust significantly alters the metabolism of AA in AM, with potentially important aspects of AA metabolism remaining altered even after a 2-wk recovery period. Based on the established role of eicosanoids in inflammatory and fibrotic processes, these results suggest that the alteration of AM eicosanoid production as a result of the inhalation of coal mine dust may be an important factor in the pathophysiology of coal workers' pneumoconiosis.The authors are grateful to Joan Greenwood and Barbara Scheetz for their excellent technical assistance and to Brenda Pavone for the preparation of the manuscript. This research was supported by the U.S. Department of The Interior's Mineral Institute Program administered through the Generic Mineral Technology Center for Respirable Dust under grant 1135142.Request for reprints should be sent to Douglas C. Kuhn, Ph.D., Department of Pathology, The M.S. Hershey Medical Center, Hershey, PA 17033.INTRODUCTIONPulmonary alveolar macrophages (AM) are activated by foreign particles and microorganisms that enter the small airways (Kass et al., 1966; Herscowitz, 1985). This defensive reaction involves phagocytosis, lysosomal enzyme release, and the generation of reactive oxygen species by the AM (Snella, 1986; Rich et al., 1987). A number of agents, including phorbol esters, zymosan, adenosine diphosphate, organic hydroperoxides, and calcium ionophore, have been shown to activate the AM in vitro (Badger, 1986; Marshall and Lands, 1986; Snella, 1986). The AM response to these activators appears to be mediated in part by the oxygenated metabolites of arachidonic acid (AA) (Bertram et al., 1988; Demers et al., 1987; Mcleish et al., 1987).The AM may metabolize AA through cyclooxygenase- and lipoxygenase- catalyzed pathways to produce a variety of eicosanoids including prostaglandin (PG) E2, thromboxane (Tx) A2, leukotriene (LT) B4, LTC4, LTD4, and several hydroxyeicosatetraenoic acid derivatives (HETEs) (Willis, 1970; Camp et al., 1983; Poubelle et al., 1986). The production of these eicosanoids may enhance the. defensive ability of the challenged lung since they stimulate chemotactic cell recruitment to the site of invasion, enhance extravasation of circulating immune cells, and promote local vasodilatation. However, continued stimulation of the AM population, with the consequent production of proinflammatory eicosanoids, may ultimately enhance the disease process by contributing to chronic bronchoconstriction, fibrosis, and the persistent release of toxic oxygen species."

Jan 1, 1990

By Kenneth G. Thomas

Since approximately 2003 we have witnessed the unprecedented escalation in commodity prices. Coupled with economic chaos following the 2008 economic downturn this has caused difficulties in controlling schedule, capital costs and operating costs for mining projects. Once again escalation has returned to commodity prices fuelled by growth in the BRIC countries especially China and Brazil. This is further exasperated by the missing generation of skilled technical personnel not graduating from universities in the 1980s and 1990s owing to depressed commodity prices. This paper examines the six tenets for successful project implementation.

Jan 1, 2011

By Larry B. Fiske

Elimination of dust and processing of fines for both thermal and metallurgical coals is addressed. The efficiency of treatment with lignosulfonates compares favorably to oil in thermal coal. Effect of treatment with various lignosulfonates upon cokability of metallurgical coal was determined by Free Swelling Index, Gieseler Plasticity and Arnu Dilatation.

Jan 1, 1992

By George Mandarakas, Johan van Zyl, Karl-Heinz Becker

The world’s climate today has changed compared to 10 or 20 years ago. Many countries face water shortages; water sourcing for mining activities has become harder to secure. ESG’s focus on the industry has made us more aware of the need to preserve and responsibly use the water needed for wet processing in our milling and sorting activities. In a recent greenfield project in South Australia, 10 Gigalitres per annum would be required to process 5Mtpa of magnetite [1]. Published information indicates that the mining industry consumes approximately 12 EJ per year—or 3.5% of total global final energy consumption globally [2] or 3.33 trillion kilowatt hrs. This energy consumption is significant, considering the critical role mining plays in extracting and processing essential minerals for economic development and human progress. The perception of the mining industry is that not only does it consume significant power, but it also consumes a lot of the freshwater in the world. In fact, it consumes approximately 5% [3] of the total freshwater demand. According to the Intergovernmental Panel on Climate Change (IPCC), by 2050, 60% of the world’s population will be living in countries that are classed as water-stressed [3]. As more and more emphasis is placed on renewable energy sources, the amount of water used in mineral processing will increase because more and more raw materials require a water-intensive process. This increases the pressure on the mining industry to try and find water-saving initiatives. As part of this review, recent advancements in magnets have enabled magnetite processing facilities to achieve between 30 to 40% dry gangue material rejection before the wet beneficiation process (grinding and sorting). This reduction in energy consumption allows the reduction of energy consumption. Secondly, there is less material ground in the mills, which requires less water for mineral downstream processing.

Feb 1, 2025

By A. R. Sorta, D. C. Sego

ABSTRACT Temperature, solute, texture, and thixotropic effects on time domain reflectometry (TDR) measurements of water content in oil sands tailings are investigated. Results indicate that TDR water content measurements are influenced by temperature, residual bitumen, and percent clay in the tailings. A correction of 0.03–0.10/ °C must be applied to the apparent dielectric constant (Ka) to account for the effect of temperature. The Ka-volumetric water content relationships of slurries differ significantly from the commonly used Topp calibration equation. The age of the tailings and the addition of phosphogypsum did not influence TDR water content measurements.

Jan 1, 2013