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Accurate hematite solubility data are required to construct predictive solution chemistry models for complex hydrometallurgical solutions. These data are useful in understanding Fe(III) speciation and precipitation in a variety of hydrometallurgical processes. Hematite solubility data were generated in 10 to 70 g/L H2SO4 solutions and at temperatures from 130 to 270°C, using specially modified titanium autoclaves. These measurements represent an improvement over previous experimental data because of better in-situ filtration of the sample aliquots, the approach to equilibrium via hematite dissolution, and the inhibition of Fe(III) reduction on titanium surfaces. Fe(III) reduction was particularly studied to evaluate the inflationary effect of Fe(II) on hematite solubility measurements. Chromate was found to reliably inhibit Fe(III) reduction on titanium. Finally, the generated hematite solubility data were used to construct a solution chemistry model using the OLI software.

Jan 1, 2006

By K. Muehlenbachs, J. U. Stemler

"Abstract - The Boston deposit is a recently discovered Archean lode-gold deposit located approximately 700 km northeast of Yellowknife, in the southern portion of the Hope Bay volcanic belt. Primary H2O-CO2-NaCl fluid inclusions associated with gold mineralization at Boston are of low salinity (4.6 ± 1.4 eq. wt.% NaCl, n = 182) and contain pure CO2. Homogenization temperatures of liquid-phase inclusions average 270° ± 33°C (n = 141), but some fluid inclusion assemblages contain coexisting liquid- and vapor-phase inclusions that homogenize near critical conditions, suggesting phase separation. In these groups, liquid-phase inclusions homogenized at 299° ± 25°C (n = 24), and vapor-phase inclusions homogenized at 338° ± 28°C (n = 18). These temperatures overlap within error, and a median temperature of ~320°C is taken as representative of trapping conditions within the veins. An approximate pressure of 2-3 kbar was estimated from fluid inclusion isochores at this temperature. Stable isotopic compositions of carbonate minerals from the mineralized zones range from -4.7‰ to -3.1‰ in d13C, and from 11.2‰ to 12.8‰ in d18O; quartz ranges from d18O = 12.8‰ to 14.9‰; and pyrite ranges from d34S = 2.1‰ to 3.5‰. The d18OH2O, d13CCO2, and d34SH2S values of the fluid calculated from these minerals at 320°C are 6‰-9‰, -2.4‰ ± 0.6‰, and 1.5‰ ± 0.5‰, respectively, and are intermediate between metamorphic and magmatic compositions. A unique source for the fluids cannot, therefore, be constrained from these data. Petrographic and geochemical data for the Boston deposit are consistent with data from other Archean lode-gold deposits worldwide, implying that the Boston deposit formed in a similar environment and from similar types of fluids. These results suggest that the Hope Bay volcanic belt may represent a major new mesothermal gold belt in this part of Nunavut. Sommaire - Le gîte Boston a été récemment découvert à environ 700 km au nord-est de Yellowknife dans la partie sud de la ceinture volcanique de Hope Bay, il s’agit d’un gîte d’or filonien d’âge Archéen. Les inclusions fluides primaires de H2O-CO2-NaCl associées à la minéralisation aurifère du gîte Boston présentent une faible salinité (4.6 ± 1.4 eq. pds.% NaCl, n = 182) et contiennent du CO2 pur. La température d’homogénéisation des inclusions à phase liquide est en moyenne de 270° ± 33°C (n = 141), mais certains assemblages d’inclusions contiennent des phases liquides et gazeuses coexistantes qui s’homogénéisent dans des conditions quasi critiques, suggérant qu’elles résultent d’une séparation de phase. Dans ces groupes, les inclusions de phase liquide s’homogénéisent à 299° ± 25°C (n = 24) et les inclusions de phase gazeuse s’homogénéisent à 338° ± 28°C (n = 18). Ces températures se recoupent à l’intérieur des limites de l'erreur de mesure, et nous considérons qu’une température médiane de ~320°C est représentative des conditions de piégeage dans ces veines. Les isochores permettent d’estimer une pression d’environ 2-3 kbar à cette température. La composition des isotopes stables des carbonates dans les zones minéralisées s’étend de -4.7‰ to -3.1‰ pour d13C et pour de 11.2‰ à 12.8‰ pour d18O; les valeurs de d18O pour le quartz varient de 12.8‰ à 14.9; et les valeurs de d34S dans la pyrite vont de 2.1‰ à 3.5‰. Les valeurs de d18OH2O, d13CCO2, et d34SH2S du fluide calculé à partir de ces minéraux à une température de 320°C est de 6-9‰, -2.4‰ ± 0.6‰, et 1.5‰ ± 0.5‰ respectivement, reflétant des conditions intermédiaires entre des compositions métamorphiques et magmatiques. Il n’est donc pas possible d’identifier une source unique pour ces fluides à partir de ces données. Les données pétrographiques et géochimiques du gîte Boston sont similaires à celles d’autres gîtes d’or filoniens ailleurs dans le monde, ce qui implique que le gîte Boston s’est formé dans un environnement similaire à partir des mêmes types de fluides. Ces résultats suggèrent que la ceinture volcanique de Hope"

Jan 1, 2006

By Robert S. Schechter

A minitest, consisting of an injection/production well and at least two observation wells designed to detect the arrival of injected fluid leached minerals, and nonideal flow, is considered in this report. The test goals are to determine the susceptibility of the host formation to uranium leaching, kinetic parameters to scale the process, and to facilitate site restoration. This report considers permeability and mineral heterogeneities and other oxidant-competing minerals. To circumvent these nonidealities, which obscure the results, methods of interpretation have been proposed and tested by a computer simulator. In complex cases, clear-cut methods of interpretation were not found; but in every case the design of a test most susceptible to interpretation has been considered. The minitest is operationally simple and can be completed in a short time. With the correct design and interpretation it can return information to evaluate economics, ensure satisfactory leachate performance, scale to larger operations, and to identify restoration problems.

Jan 1, 1983

Stellite-6 coatings were formulated on two Ni-base superalloys, namely Superni 75 and Superni 600, by a shrouded plasma-spray process, and the oxidation behaviour of these coatings has been investigated in air and in an aggressive environment of Na2SO4- 60%V2O5. Accelerated oxidation tests were conducted in a silicon-carbide tube furnace under cyclic conditions at an elevated temperature of 900°C for 50 cycles. Each cycle consisted of 1 h heating and 20 min cooling in air. A thermogravimetric technique was used to approximate the oxidation kinetics. The corrosion scales were characterised by XRD, SEM/EDAX and EPMA analysis. It has been observed that the coatings nearly followed the parabolic rate law of oxidation. Overall weight gain conceived in air was just 51% of that in the aggressive environment in the case of coated Superni 75, whereas in case of coated Superni 600, the cumulative weight gain in air was found to be one-third of that in the Na2SO4-60% V2O5 atmosphere. Furthermore, the coating showed very good adherence to both of the substrates during the course of air oxidation, whereas some superficial cracks were observed near the edges of the specimens during the molten salt induced oxidation. XRD analysis revealed the presence of phase-like CoO, CoCr2O4 and Cr2O3 in the oxide scales, which are reported be protective against high-temperature oxidation. The XRD results were further supported by SEM/EDAX and EPMA.

Jan 1, 2005

By Manuel Sierra Lopez

Southern Perú Copper Corporation sucursal del Perú es una empresa de propiedad del Grupo México, realiza actividades minero metalúrgicas en las regiones de Moquegua y Tacna, explotando las unidades de producción de Toquepala y Cuajone siendo utilizado el método de explotación de Tajo abierto. Además Southern Perú Copper Corporation cuenta con una fundición de cobre ubicada en la Ciudad de Ilo y un patio puerto de donde se traslada los ánodos y cátodos de cobre a los mercados internacionales. Southern Perú, mediante su política de Responsabilidad Social Empresarial (RSE), viene desarrollando diferentes programas y proyectos; los cuales, buscan contribuir con el desarrollo del territorio mediante el fortalecimiento y desarrollo de capacidades técnico productivas.

Sep 1, 2017

By D. J. Donaldson

The PAL process for recovering nickel from laterite ore requires large volumes of thick abrasive slurry to be raised lo high temperature (245°C+) and pressure (40 atm.+). Flow diagrams of the process typically result in facilities that have serious operating and reliability problems. Most of the problems can be attributed to using multiple pump stations to raise the slurry to autoclave pressure, large amounts of flash and live injection steam to heat the slurry to autoclave temperature and several steps of flash cooling to lower the temperature and pressure of the abrasive autoclave slurry down to atmospheric conditions. It is proposed that operating and reliability problems of PAL facilities can be mitigated by using Tube-in-tube heat exchangers and "float type" positive displacement pumps. The subject paper describes an innovative application of such equipment in the facility design of the PAL process. Keywords: Nickel, Laterite, PAL, Heating, Slurry

Jan 1, 2004

By A. J. Sinclair, N. Champigny

"The Cinola gold deposit in the northern Queen Charlotte Islands, British Columbia, is in a clastic sequence consisting of a lower shale of the Late Cretaceous Haida Formation and an overlying interbedded sequence of pebble conglomerate and coarse-grained sandstone of the Middle Miocene Skonun Formation. Both formations are intruded by a stock and dykes of porphyritic rhyolite. Two K-Ar model ages indicate mineralization and probably porphyritic-rhyolite intrusion at about 14 Ma (middle Miocene). A splay of the Sandspit fault system constitutes the footwall on the west of the deposit.The Cinola deposit can be classed as Carlin-type based on features such as (1) small particle size for gold, (2) Tertiary age of mineralization, (3) element abundances (e.g. high Hg), (4) dominantly argillic alteration, (5) a structural setting associated with major faults, (6) porosity of the host rock and (7) spatial and possibly genetic association with felsic intrusions. Gold is widespread and occurs mainly as grains of< 0.5 11-m in silicified sedimentary rock, and in quartz veins. Locally, coarse > 100 11-m particles of native gold occur in quartz veins, especially in strongly brecciated porphyritic-rhyolite. Ore minerals are mainly pyrite and marcasite, but include small amounts of chalcopyrite, sphalerite, galena, pyrrhotite, cinnabar, tiemannite (HgSe), rutile, magnetite, hematite and limonite in addition to native gold and electrum. No silver minerals have been found; silver was found in gold particles in amounts varying from 6.2 to 24.2 weight per cent. Alteration products are sericite, illite, kaolinite and chlorite, with abundant quartz of several stages.The host rocks, specifically the Skonun Formation, formed as an alluvial plain facies in a braided river system discharging into a marine basin in early Middle Miocene time. During the Middle Miocene, this sequence was intruded by a rhyolitic stock. The highly porous and permeable Miocene clastic sequence apparently provided an optimum setting for the development of a large geothermal system, the energy for which probably derived from the rhyolite stock. Mineral deposition followed a well-defined paragenesis, which, from oldest to youngest, is: (1) precipitation of iron sulphide minerals, and early quartz; (2) several stqges of quartz veins, with deposition of sphalerite succeeded by galena, chalcopyrite and visible gold. Micron-size gold was precipitated throughout these two stages of mineral deposition. Argillitization of the host rocks probably in part coincided with the mineralization and continued during cooling of the geothermal cell.In-situ reserves have been estimated at 41.1 million metric tons averaging 1.85 g Au/tonne using a cutoff grade of0.86 g Au/ tonne."

Jan 1, 1982

By Hans Lundberg

Jan 1, 1927

By Ronald H. Church

The Bureau of Mines tested & ground penetrating radar (GPR) system in the central Florida phosphate district. to determine the feasibility of utilizing GPR technology for subsurface cavity detection. The test area is located in karst topography where sinkhole development is prevalent. State regulations require subsurface drilling of damsites to identify underground anomalies; however, this method is not totally accurate in locating subsurface cavities that could lead to sinkhole development. An electromagnetic method of identifying anoma-lous subsurface conditions could reduce or eliminate the possibility of dam failure due to sinkhole development. The Bureau devised a GPR system that successfully penetrated over 50 ft of overburden and gave recognizable radar return signals characteristic of a rock-cavity interface.

Jan 1, 1986

By J. Trow

Dowsing is really IESG which inductively locates electric gradients (dv/dx) on the flanks of SP anomalies. "Sensors" are in one?s head. The "meter" consists of one?s body, limbs, and two $.69 welding rods. The method was calibrated near Mamainse Point, Ontario, where IESG-negative chalcopyrite-bornite-chalcocite-native copper ores reveal mineral zoning related to the IESG-positive Keweenaw fault, down which oxidizing solutions moved. In Michigan, the IESG-positive Keweenaw fault suggests that oxygen-bearing solutions from the Jacobsville Sandstone moved downward to oxidize hydrothermal sulfur to produce native copper, and to supply sufficient water to satisfy Walter White.

Jan 1, 1992

By M. Deutsch, E. González, M. Williams

"Uncertainty exists in ultimate-pit limits due to geologic variation and unpredictable economic landscapes. In this work, we show how this uncertainty affects the ultimate pit and how it can be analyzed to improve the mine planning process. A stochastic framework using geostatistical simulation and parametric analysis was used to model the effects of geologic and economic variations on ultimate-pit limits and overall project economics. This analysis was made possible by a new pit optimization implementation that can be automated and set up to calculate ultimate pits for hundreds of different scenarios in a matter of hours. Quantifying ultimate-pit uncertainty early in the mine planning process allows mining engineers to make informed decisions regarding infrastructure placement and to mitigate the possibility of incurring substantial costs to relocate critical mine facilities. Resumen ¦ Existen dudas sobre los límites del pit final por causa de la variación geológica y lo impredecible de los paisajes económicos. En este trabajo les mostramos como esta incertidumbre afecta el pit final y como puede ser analizada para mejorar el proceso de planificación de la mina. Se usó un marco estocástico con simulación geoestadística de análisis paramétrico con el fin de poder hace la modelación de los efectos de las variaciones geológicas y económicas en los límites de pit finales y proyectos económicos en general. Este análisis fue posible gracias a una nueva implementación de optimización de pits que puede ser automatizada y configurada para calcular pits finales para cientos de escenarios diferentes en cuestión de horas. La cuantificación temprana de la falta de certeza en pits finales durante el proceso de planificación permite a los ingenieros de minas tomar decisiones informadas en lo que respecta a la ubicación de infraestructura y en la mitigación de posibles costos sustanciales por causa de la reubicación de instalaciones clave de la mina."

Jan 1, 2015

By Robert E. Wallhagen

This report describes the results of a four year investigation into improved face ventilation systems for underground coal mines. The objective was to experimentally determine configurations for a diffuser fan system and a water spray (spray fan) system which will provide a maximum reduction in face methane concentrations without causing an increase in methane concentrations at the operator&apos;s position. The experimental evaluation was performed in full scale mock-up mine entries, simulating continuous mining operations in both a six foot and four foot coal seam complete with normal ventilation, water sprays, and methane emission. A limited study was also performed to assess the effect of scrubber discharge location on methane concentrations in the face area. The results indicated that diffuser fan and spray fan systems that were designed to augment the natural airflow pattern in the entry could provide a factor of 3 to 5 reduction in average methane concentration at the face, compared to a mining machine with just conventional water sprays. The properly designed diffuser and spray fan systems also significantly reduced the total methane present in the entry. A properly designed dust scrubber discharge can reduce face methane levels by a factor of two.

Jan 1, 1977

By Margaret Anne Stephenson

While the concepts of Aboriginal title share a similar jurisprudence in both Australia and Canada resource development regimes on Aboriginal title lands differ significantly. In Australia, the process is the right to negotiate with mining proponents. In Canada, the process is the duty to consult with government regarding mining projects. This paper compares and assesses the processes for ?consultation and negotiation? with Indigenous peoples when development actions (particularly in the context of mining resource development) impact Indigenous property rights and how agreement making can be progressed. This paper will question whether the resource development processes afford Indigenous people?s property rights full respect when mining developments on Indigenous lands are proposed.

Aug 1, 2013

By C. D. M. Chisholm

IN discussing stope filling, or backfilling, at the Sullivan mine, at Kimberley, B.C., a brief description of the problem will first be presented. The Sullivan orebody is a replacement in quartzite, with the ore con-forming, for the most part, with the bedding. The dip of the vein, apart from local irregularities, averages about 15 degrees near the outcrop in the southwest section of the mine, and steepens to almost 40 degrees at the northeast end of the mine. The thickness varies from a few feet to over 200 feet at the widest sections. The mineable length along the strike has averaged about 4,000 feet between the 4,600 and 3,900 levels-the section under discussion in this paper. To date, 28,000,000 tons of ore have been mined by the room-and-pillar method. Prior to 1930, all ground opened up had been supported by ore pillars, left during mining operations. From that time, the recovery of the ore from these pillars has been given serious consideration. Backfilling, as being carried on today, is the result of this study and is being done for two reasons: (1) to allow extraction of the ore pillars, and (2) to minimize subsidence of the hanging-wall rock, except where forced caving is found desirable. PRELIMINARY DEVELOPMENTS LEADING TO BACKFILLING When the Sullivan orebody was first opened up, early in the century, there appeared to be low-grade sections of the vein sufficient in extent to serve as permanent support for the roof. However, as mining extended into sections of the vein that showed continuous ore over greater areas, wooden cribs, filled with waste and low-grade ore, were erected. In some stopes, these cribs were as large as 40 ft. by 100 ft. in plan and from 50 ft. to 60 ft. in height, but it was soon realized that this method of support was inadequate. As mining progressed, it was found necessary to leave ore pillars, which eventually became the sole system of support. At first, these pillars were left at irregular intervals, but later they were laid out at definite locations on the mine plans, and these locations were adhered to as closely as mining would permit.

Jan 1, 1941

By E. Knell

COM Energy, Inc., a subsidiary of Occidental Petroleum Corporation, has constructed a 1.6 million hectoliter-per-year COM plant in Jacksonville, Florida. COM will be distributed to customers in the region as a substitute for fuel oil presently burned in boilers and kilns. As the market for COM grows, COM Energy, Inc. expects to build additional units both in this country and overseas. This paper addresses the overall status and technical aspects of the project, focusing on the facilities for COM production and utilization.

Jan 1, 1982

By H. Dolezal

A laboratory study of acid-ferrous sulfate treatment of low-grade manganese ores from the Cuyuna range, Minnesota resulted in 93-percent extraction of manganese as manganese sulfate with consumption of 3.8 pounds of H2S04 per pound of extracted manganese. Two types of ore were treated in consecutive stages. The first are contained carbonate minerals of manganese and iron, both soluble in H2S04 solution. The second ore contained manganese oxide minerals, insoluble in straight acid solution but soluble in the ferrous sulfate solution obtained from treating the first ore. Leaching data were obtained by countercurrent percolation of coarse (minus-1/2-inch) ore particles at room temperature and by agitating minus-65-mesh ore particles in heated solution. Extraction of manganese and acid consumption were the same, but the percolation leach required 6 days compared with 1 hour for hot agitation. Variations in the size of ore particles treated, leaching time, acid concentration, solution temperatures, and method of applying ferrous sulfate solution to the oxide ore were studied. The effects of several reagents for removing iron from solution and improving filtration were also studied.

Jan 1, 1959

By M. J. Dailey

This paper is one of a series being prepared by the United States Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The property of the Silver King Coalition Mines Co. is situated in the western past of the Park City mining district, Utah, about 1 ½ miles southwest of the town of Park City, The elevation at the collar of the main shaft is 8,137 feet above sea-level.

Jan 1, 1930

By Osvaldo A. Bascur, Curt Heftier

The lack of integrated information including the Energy/Utility Suppliers with sufficient detail for analysis causes inefficient operation in metallurgical complexes including the Energy/Utility Suppliers . Defining the right context for information use is essential for sustainable operations. This being said, what are we doing to enable people to act upon information and to be aligned to optimize the use of resources like raw materials, energy, water and consumables for an entire metallurgical complex? Collaboration between all company entities is a key component of improving efficiency. Evolution of web technology and object modeling of enterprise assets enables collaboration across the whole business. Operational troubleshooting occurs more quickly as the organization acts on issues to reduce wasteful operation. This paper presents a real time software infrastructure with tools that give users the ability to sift through available data, transform data into information for business continuous improvement and optimization. We will introduce a new technology for analyzing real time data, information and events using multidimensional analysis of information to detect anomalies based on the statistics of the data classified by time events to reduce the information into action. A new paradigm for collaboration at a local and strategic level is proposed to enable the enterprise to become proactive in dealing with wasted time and products. Three examples from the industry will presented and their benefits highlighted.

Jan 1, 2011

By Kimio Itagaki

The distribution behaviours of the VA elements between the gas, slag and matte phases in copper smelting were evaluated on the basis of the thermodynamic data, most of which were determined by the authors. The distribution is basically dependent on the process factors such as temperature, the content of the element in charge, the amount of the waste gas and degree of vapour saturation with the elements. The thermodynamic quantities such as the activity coefficients of the VA elements in matte, the activities of iron and copper, SO2 or 02 potential and the distribution ratio of the elements between the slag and matte phases seriously affect the distribution, and the behaviours in various smelters could be explained systematically and reasonably by considering the changes in these quantities, In oxidation smelting at PSO2= 0.1 to 1 atm, the proportion of arsenic and bismuth in gas is predomi22t for the arsenic and bismuth distributions in both smelting and converting stages. The degree of vapour saturation has serious effect on the distribution, and sufficient contact between gas and matte phases is desirable for transferring arsenic and bismuth into gas phase.The elimination of antimony by means of vaporization is not significant. In reduction smelting at po2 = 10-11 atm, the proportions of arsenic and antimony in the gas phase are quite small, but the proportion of bismuth does not change significantly.

Jan 1, 1983

By Walter Crooke

Regenerative hot-blast stoves are now in general use in all parts of the world, and are so well understood and appreciated, that I need not take up your time with an account of their history and introduction into the United States. My object in writing this paper is to give you a short description of a stove that is now being very favorably received and adopted here (see drawing). The stove was first introduced into this country in 1887 by M&apos;Clure & Shuler (now M&apos;Clure & Amsler), who have the management of the patent right in the United States. The English design had to be modified to suit the exigencies of American blast-furnace practice, which, in many respects, widely differs from our English experience. In the first place, the fire-bricks used in America expand to an extent unknown in England, and it became necessary to make special provision for this by increasing the number of cross-walls, and by leaving a space at the top of the stove through which the lining could expand. The expansion laterally was, however, more difficult to provide for, as the combustion-chamber in the center, being the hottest part of the stove, must necessarily expand more than the outer walls, and therefore tend to squeeze up the flue-openings. On first introducing these stoves to American ironmasters, a feel ing seemed to prevail that a " four-pass " stove did not utilize the whole of its surface. They also had an idea that the " two-pass " stove let the burning gas go before all the duty had been extracted from it; so that it was found neceseary to design a stove of a special character to suit their wishes. Hence the "three-pass" chimney top stove now before your notice, the advantage claimed for which is that each stove is independent, requiring no underground chimney flue or stack, and can be erected at a very light cost. The working of these stoves has proved to be very successful wherever they have been introduced.

Jan 1, 1891