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The Kingsgate molybdenite pipes are considered on petrochemical data and field occurrence to be, possibly, epi-magmatic plutonic offshoots grading into hydrothermal bodies. There is reason to believe that the ore is derived from a highly acid granite of type similar to that of the tin bearing areas of northern New England. The mineralogy, microtextures and paragenesis of the ore are discussed.INTRODUCTIONThe Kingsgate Mining Field is situated in steep, heavily timbered terrain 18 miles E.N.E. of Glen Innes and 430 miles north of Sydney. Bismuth and molybdenum ores were discovered at Kingsgate (Yarrow Creek) in 1877. Subsequently some 50 pipes were developed yielding tonnages which at the peak of operations, 1905 to 1920, rivalled production from the rich deposits of northern Queensland.Attempts to revive the field have been made periodically and small parcels of ore have been forthcoming.' During World War II demand for piezioelectric quartz again focussed attention on Kingsgate but twinning and other imperfections of the quartz prevented all but a minor exploitation of the otherwise noteworthy crystals of this locality.There is reason to believe that the ore at Kingsgate is not exhausted through exploration and mining costs would probably be high due to the capricious nature of the pipes and to the irregular distribution of rich ore shoots within them.

Jan 1, 1962

By M. Abdellatif

Keywords: Magnesium, pyrometallurgy, Mintek Samples of crude magnesium produced by the Mintek Thermal Magnesium Process were refined in two stages. The first stage consisted of co-melting of batches of the crude metal and MgCl2-KCl flux (cleaning), followed by stirring at 30 rpm for 30 minutes and settling of the sludge (mixture of molten salt and solid impurities) from the magnesium melt. The operating temperature was 680?730°C. Most of the contained calcium and significant proportions of iron and silicon were transferred into the sludge phase, which left a metal containing, on average, 950 ppm Si, 470 ppm Fe, and 230 ppm Ca. In the second stage, small-scale refining tests were conducted on cleaned samples from the first stage, as well as on crude magnesium. FeCl3 was used as the refining agent. These tests were carried out at 715?760°C with various amounts of the refining agent. The refined metal was suitable for the production of various magnesium alloys, particularly AZ91D.

Jan 1, 2006

Microfluidic Solvent Extraction for Mineral Processing of Copper Leach Solutions

Sep 13, 2010

By M. D. Max, A. H. Johnson

INTRODUCTION Gas hydrates have considerable potential to be a major energy resource owing to their apparent abundance in Arctic regions and along continental margins throughout the world (Kvenvolden, 1988). Yet, the oil and gas industry has been slow to pursue this opportunity. The primary reasons for this are the large conventional reserve base for natural gas worldwide and the perception that gas hydrate will not be a viable resource for another twenty or thirty years. Gas hydrates are thus viewed as a potential resource for the distant future, but not a valid investment for the near term. This paper addresses both global gas markets and gas hydrate technology, and shows that the commercial development of gas hydrate could proceed rapidly enough to constitute a near-term energy resource. GLOBAL GAS MARKETS The proven worldwide reserves of conventional natural gas are truly enormous, totaling over 6,000 TCF according to BP (2004). Moreover, those reserves have nearly doubled during the past two decades and now represent 67 years of consumption at the current production rates of 80 TCF per year (Fig. 1). This reserve increase has occurred even as global production of natural gas has increased by 67% during the same two decades (Fig. 2). While declining conventional gas reserves are a concern in North America, especially in regions where established infrastructure exists to bring gas to consumers, large new discoveries continue to be made elsewhere in the world. Indeed, in many parts of the world (such as the Middle East and parts of West Africa), natural gas has been regarded as an essentially worthless byproduct of oil production or exists in stranded gas fields. Given this situation, pursuing unconventional gas resources that are inherently riskier exploration targets and more expensive to produce would appear to have little rationale from a business standpoint.

Jan 1, 2006

By A. K. Anyimadu

Ongoing development work on ultra-fine grinding for various applications at the Group?s concentrators has been conducted by Anglo Platinum over the last few years. Current potential applications for mainstream grinding and concentrate grinding are the subject of a group-wide research and development programme. The first 10 000-litre 2.6 MW IsaMill was jointly developed by Anglo Platinum, Xstrata Technology and Netszch for installation at the Western Limb Tailings Re-treatment project in Rustenburg, South Africa. The unit was commissioned in late 2003/early 2004,and has operated in an intermediate concentrate regrind application successfully since. This paper describes the operational performance to date, as compared with the original duty specifications and objectives. The first mainstream M10 000 IsaMill with a 3 MW drive will be operational in November 2006 at the Potgietersrus Platinum (PPL) ?Platreef? Sandsloot Concentrator in South Africa?s Limpopo Province. Keywords: Western Limb Tailings Re-treatment Plant, IsaMilling, Platreef, platinum, palladium, PGMs, tailings.

Jan 1, 2007

By Oswaldo Ortiz Sánchez

El presente trabajo describe la alternativa de uso del mortero de resina en la fijación de pernos de anclaje de las excavaciones mineras, consolidación y disipación de vibraciones en los cimientos de plataformas para la instalación de molinos, winches, tolvas, etc. Esta opción surge en respuesta al problema de reforzamiento con pernos de anclaje en ambientes con aguas corrosivas o en proceso de deformación acelerada en las excavaciones mineras, así como ante obstáculos de subsidencia de cimentación en plataformas, donde se encuentran instalados equipos de gran tonelaje, y que producen fuertes vibraciones durante su funcionamiento.

Jul 31, 2003

By Gonzalo Chávez

El presente texto describe la lixiviación de oro con tiourea como una alternativa viable para la recuperación de dicho mineral, así como para el medio ambiente. En este sentido, la lixiviación de minerales de oro con solución ácida de tiourea fue evaluada con el uso de carbón activado, re-extracción y electrodeposición, obteniéndose velocidades de reacción y recuperación similares a los obtenidos con cianuro.

Sep 12, 2011

By J. C. Vreugdenburg, B. A. Dippenaar, J. Muller, T. L. de Vries

Iron ore fines are agglomerated to produce sinter, which is an important feed material for blast furnaces worldwide. A model of the iron ore sintering process has been developed with the objective of being representative of the sinter pot test, the standard laboratory process in which the behaviour of specific sinter feed mixtures is evaluated. The model aims to predict sinter quality, including chemical quality and physical strength, as well as key sinter process performance parameters such as production rate and fuel consumption rate. The model uses the finite difference method (FDM) to solve heat and mass distributions within the sinter pot over the height and time dimensions. This model can further be used for establishing empirical relationships between modelled parameters and measured sinter properties. Inputs into the model include the feed material physical properties, chemical compositions, and boundary conditions. Submodels describe relationships between applied pressure differential and gas flow rate through the bed of granulated fine ore particles, combustion of carbonaceous material, calcination of fluxes, evaporation and condensation of water, and melting and solidification. The model was applied to typical sinter test conditions to illustrate the results predicted, and to test sensitivities to parameters such as feed void fraction, feed coke percentage, and the fraction of combustion heat transferred to the gas phase. A model validation and improvement study should follow, ensuring sinter test results are free from experimental errors by conducting repeated tests.

Jan 1, 2015

Sulfidisation Promotion Effect of Ammonium Sulfate on the Flotation of Copper Oxide Ores

Sep 13, 2010

By Aram Grigoryan

This paper addresses the challenges of designing the underpinning of major sub-way station with 4 operating tracks. No. 7 subway extension crosses under the existing 42nd street subway station on the 8th Avenue line. Understanding the history of the original construction, of the current structures and their condition were instrumental in developing a feasible underpinning design that is integrated with the design of the new tunnels. The existing 8th Avenue subway station has a lower abandoned level. Several alignments and corresponding underpinning schemes were studied. The design allows new tunnel construction under the station without interruption of station operations.

Abrasivity and wear resistance are not intrinsic properties of materials, but rather parameters describing the interaction between the wear part and the material exerting the wearing action. Moreover, wear or, at least, that part of the wear which is due to the cumulative effect of minute scratches, is linked to the hardness disparity concept. Abrasivity, in this context, is a relative concept, pertaining to a metal-rock pair, rather than to a rock. Based on this assumption, a methodology has been developed and checked against actual cases, enabling description of the abrasiveness of arock or the abrasion resistance of a metal through the ratio of comparable quantitative indicators. The paper describes the methods and provides examples of applications to practical cases(namely: rock cutting, excavation by means of tunnel boring machines (TBMs), rock crushing, and hydro-mill cutting).

Jan 1, 2012

By M. S. Ellis, D. J. Nichols

In 1999, 1,100 million short tons of coal were produced in the United States, 38 percent from the Northern Rocky Mountains and Great Plains region. This coal has low ash content, and has sulfur content in compliance with Clean Air Act standards (U.S. Statutes at Large, 1990). The National Coal Resource Assessment for this region includes geologic, stratigraphic, palynologic, and geochemical studies and resource calculations for 18 major coal zones in the Powder River, Williston, Green River, Hanna, and Carbon Basins. Calculated resources are 660,000 million short tons. Results of the study are available in U.S. Geological Survey Professional Paper 1625-A (Fort Union Coal Assessment Team, 1999) and Open-File Report 99-376 (Flores and others, 1999) in CD-ROM format.

Jan 1, 2001

By Phil N

A large number of experiments have been carried out by many workers on the recrystallization of deformed and subsequently annealed metals and alloys. Although observations on single crystals are of great importance in the study of the recrystallization textures of deformed and annealed metals, very little of this work deals with material in this form.Since, in deformed metals, the stress concentration is greatest at the grain boundaries and along the planes of slipping, it is to be expected that recrystallization will start in these regions. For example, in polycrystalline aluminium (1),:1: (2), copper (3), a-iron (4) and brass (5), (6), which had been deformed by cold-rolling, drawing, pressing or stretching and then annealed, the new grains first appeared in the boundaries of the original crystals, whilst in the case of cupronickel (7) and iron (8), recrystallization commenced along the slip planes of the deformed material. Deformed and annealed single crystals of aluminium (9) and cadmium (10) first start to recrystallize along slip planes and in deformation twins.The present work deals with the process of recrystallization of single crystals of lead after deformatjon by creep.Two factors enter into these experiments that were not met with in other work on this subject. Firstly, lead...

Jan 1, 1940

By . Jaime G Tapia Aguirre

La Unidad Minera Rosaura del Grupo Glencore fue considerada la mina subterránea más segura del país durante los años 2005, 2006 y 2007. Sin embargo, cuando el Grupo Glencore adquirió la concesión de Rosaura, el panorama minero era de una mina marginal, de bajas leyes. Por esta razón, el único metodo a ejecutar para hacer de Rosaura una mina rentable era el de utilizar un método masivo. Em ese semtido, el presente texto señala la operación de mina cone el análisis y conocimiento de causa raíz en la prevención de caída de roca.

Sep 12, 2011

Modelling and simulation are important aspects of flotation research, which may assist in the design of new circuits and the optimisation of existing ones. Flotation research in the AMIRA P9 project has developed a methodology for flotation plant modelling based on determination of cell (pulp) characteristics. froth characteristics, and ore floatability (using floatability components). The implementation of this methodology requires the determination of ore floatability, to which end a small flotation pilot plant known as the Floatability Characterisation Test Rig (FCTR) has been designed and then built and kindly made available to the AMIRA P9 project by Baker Process. The FCTR has a 2 tph capacity and consists of six 130 litre rougher/scavenger cells and six 50 litre cleaner/recleaner cells. The Mintek FloatStar pulp level control system is used to control the pulp level in all cells. A number of experimental procedures have been developed for using the FCTR to obtain the data required for the P9 flotation models. These procedures include how to determine the floatability parameters, Pi and mi, the bubble surface area flux, Sb, the mean residence of the pulp in the cell, t, water recovery. Rw, froth zone recovery, Rf, and the degree of entrainment, ENT. The flexibility of the FCTR allows it to be used in numerous flotation studies such as stream characterisation, reagent testing, grinding experiments, power studies, oxidation studies, and scale-up and simulation studies. This paper will describe the design and operation of the FCTR and the procedures that will be used to obtain data from the rig for modelling purposes.

Jan 1, 2000

By B Xiao, J Yang, H Chen

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Tuwu-Yandong Cu deposit, located in the East Tianshan mountains in the eastern section of the Central Asian Orogenic Belt, is the largest and economically most important porphyry Cu deposit in Xinjiang, China. It contains ~3 Mt of copper at an average grade of 0.46 per cent Cu and 0.2 g/t Au, with significant amounts of Mo and Ag. The deposit is mainly hosted in the Carboniferous Qi’eshan Group and plagiogranite porphyry, and is controlled by faults that are east–west-, north-west- and north-east-trending. Ore minerals in the Tuwu-Yandong deposit are dominated by pyrite, chalcopyrite and molybdenite, with minor bornite, chalcocite, magnetite, sphalerite and galena. Gangue minerals are mainly composed of quartz, sericite, chlorite, epidote, anhydrite, gypsum, muscovite, biotite, phosphorite, sphene, dolomite, actinolite, barite, albite and calcite. Based on the megascopic and microscopic textural relationships and mineral assemblages, five stages of hydrothermal alteration and hypogene mineralisation are recognized in the Tuwu-Yandong Cu deposit: the potassic stage, propylitic stage, phyllic stage, late veins stage and supergene stage. Most of the copper was deposited during the phyllic stage, along with less molybdenite.CITATION:Xiao, B, Chen, H, Wang, Y and Yang, J, 2015. Geology, mineralisation and alteration of the Tuwu-Yandong porphyry Cu deposit, north-west China, in Proceedings PACRIM 2015 Congress, pp 641–644 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By S. Kelebek

DETA exhibits a highly selective depressant action on pyrrhotite without adversely affecting the collectorless flotability of pentlandite and chalcopyrite in nickel-copper ores of the Sudbury region. A simplified Eh-pH diagram has been constructed to illustrate the extended stability of elemental sulphur and to explain the collectorless flotation of pentlandite and chalcopyrite. Cu and Ni ions, which are known to exist on the surface of pyrrhotite, promote the flotation of this mineral whether a collector is present or not. Thermodynamic calculations indicate that the action of DETA involves the sequestration of Cu and Ni ions from surfaces under a wide range of redox conditions; analysis of flotation test filtrate indicates as much as a 20-fold increase in the concentration of Ni and Cu ions. It appears that DETA may enhance the self-hydrophobicity of chalcopyrite and pentlandite by exposing more of the sulphur-rich surface sites for bubble contact in flotation. There are various possible explanations for its depression of pyrrhotite

Jun 18, 1905

By M. Feely, W. G. O'Keefe, C. O'Reilly, M. P. Holdstock

A petrographic and microthermometric study of fluid inclusions in the Kentstown Granite, crosscutting quartz (VI) and calcite+quartz (V 2) veins in the granite and calcite+quartz (V 2) veins in the overlying sediments was performed on samples taken from the borehole. Comparisons of the type 1, type 2 and type 3 fluid inclusion populations recorded in the present study with those from other Irish Caledonian granites strongly suggest a similar fluid evolutionary history. Furthermore, the low-temperature CaC12-rich brines (type 5) of this study, which must be syn- to post-Lower Carboniferous in age, have correlatives both in Irish Caledonian granites and in the Lower Carboniferous base-metal deposits of the Irish midlands

Jun 19, 1905

By John S. Ball

[A system of analysis for sulfur groups in petroleum distillates has been developed as one phase of the Bureau-of Nines investigation of the more economic utilization of the so-called "black oils" of Wyoming,. This problem is being studied by the Bureau of Nines under a cooperative agreement with the University of Wyoming at the Bureau's Petroleum Experiment Station, Laramie, Wyo. Wyoming black oils have high sulfur and asphalt content and usually yield only small percentages of straight-run gasoline. A more detailed description of the properties of black oilshas been given in a previous publication (3)3/. The preparation and properties of asphalts from those oils have been described (1, 2), end the effect of thermal cracking and the use of ordinary methods of treating wore discussed in one Bureau publication (4), Although these studies gave considerable insight into the properties and characteristics of black oil, it was thought t that a more fundamental attack would assist materially in the problem of sulfur removal.]

Jan 1, 1941

By S. H. Ash

THIS REPORT covers the second in a series of five projects into which the Conowingo tunnel system has been divided for geographical and practical reasons. It outlines the construction work contemplated-to sink two shafts on the line of the main tunnel that are designated the Nos. 9A and 11 shafts, to turn off from the No. 9A shaft the Lansford and Lykens laterals, and to drive portions of the main tunnel. An emergency pumping plant, consisting of 2 separate pumprooms, each containing 3 horizontal-type centrifugal pumps of 100,000-gallons-per-minute (g. p. m.) capacity, will be constructed at the No. 9A shaft. From the No. 11 shaft will be turned off the Trevorton lateral and portions of the main tunnel, which will connect with the section driven from the No. 9A shaft. Under the proposed project, the Lansford lateral will be driven for a distance of 2 miles, the Lykens lateral for a distance of 10.56 miles, and the Trevorton lateral for a distance of 20 miles. To drive the Lykens and Trevorton laterals for the distance indicated, several construction shafts and slopes must be sunk to permit efficient and safe construction.

Jan 1, 1955