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By Yuya Nakai, Kuniaki Murase, Kazuhiro Fukami, Atsushi Kitada, Ken Adachi

The resources of vanadium –titanium magnetite in China are very abundant, most of which are used to prepare titanium-rich materials. Titanium pigment, electric welding bar and titanium sponge are made from titanium-rich materials such as synthetic rutile and titanium slag etc. To fully utilize titanium resources, many production methods of titanium-rich materials were proposed. In this article, authors review on methods of preparing titanium-rich materials which are Electric Smelting Process, Reduction-rust Process, Selective Chlorination Process, Acid Leaching Process, and sum the advantages and disadvantages of them. Existing problems and possible tendency of production methods of titanium-rich materials are also discussed.

Mar 1, 2018

By Philip Nash, Jie Zhou, Joshua Blackketter

"Large ingots tend to have internal defects such as shrinkage cavities and porosities, which have to be closed during the cogging stage to ensure sound internal quality of forged parts. In this work, finite element methods were used to simulate open die forging passes, with varying parameters that affect the void closure behavior profoundly. Numerical models ware constructed in ABAQUS, DEFORM and FORGE using data taken from footage of the forging process and material mechanical data obtained from the Gleeble compression tests. Forging variables such as pass rotation, reduction per pass, and feed ratio were studied with intense attention paid on the special properties of H13 steel, so that this study can be applied to solve real world problem.IntroductionCenterline defect closure is a frequently studied but still challenging topic in open die forging industry. In practice, open die forging is employed as an effective hot forming process to make desired shape of metal products as well as to ensure center consolidation of internal defects which result from the casting process. Nowadays, remarkable large forgings have been more and more required to meet industries demand. However, the increase in ingot size has tended to result in considerable macrosegregations and shrinkage cavities or voids, which need to be worked thoroughly during the forging process; but the size of the products and limitations of manufacturing capacity, such as the press load, make it difficult to achieve adequate local deformation to close those defects. Therefore, choosing optimal forging parameters under given work condition to ensure good internal quality of forged products is critically important."

Jan 1, 2012

By J Meikle

A projected image is not always a true representation of a situation, or indeed an industry. This is often the case of the mining and minerals industry, which has frequently been portrayed in a negative light with a male dominance stigma attached. However, these issues can be combated for both the industry and its future, current undergraduate students, through undergraduate industry experience. In particular, vacation work enables female students to dispel many myths surrounding the industry and realise that the mining and minerals field offers career development for both genders. This paper will discuss how vacation work enables students to make important career decisions even before they have graduated. Industry experience provides undergraduates with the opportunity to gain practical knowledge relevant to their field of study. Additionally it allows students to observe the nature of the industry and the sacrifices necessary to advance careers. The prior insights into an industry are relevant to all students, but particularly female students, who might otherwise be dissuaded from a career in mining. This paper is written from the perspective of two female undergraduate students studying Mining and Minerals Processing Engineering.

Jan 1, 2006

By Patricia Curtis Petty

Thirty years ago, the appearance of a female mining engineer, geologist or miner in a company, union or mine environment would have been unthought of, unwelcomed and violently opposed. Twenty years ago, the intellectual perception of the news that women were interested in becoming mining engineers, geologists and miners had been accepted by the industry-but no one wanted to be the first to hire one of these exotic creatures. Ten years ago, those who had been most vehemently opposed to the philosophical idea of women working in these areas were faced with competent, productive engineers, geologists and miners-who only incidentally happened to be women-and began hiring them. Historically, of course, one can always find the isolated individual who worked in these areas-the first female graduate of the Colorado School of Mines with a mining engineering degree graduated in 1903-but the concept of woman as professional engineer was very slow in arriving in the United States. The few who worked as miners generally worked in small family enterprises, such as some of the coal mines in both Eastern and Western United States. Others accompanied husbands or sons into wilderness areas searching for gold and other precious metals.

Jan 1, 1984

By T. Brozell

"Communities near sand mines and processing facilities in Wisconsin have raised concerns regarding possible exposure to ambient respirable (PM4) crystalline silica. Fenceline PM4 (particulate matter captured with a 50 percent cut size of 4 micrometers aerodynamic diameter) crystalline silica concentration data were compiled at Fairmount Santrol Inc., Mathy Construction Inc. and U.S. Silica facilities. The long-term average PM4 crystalline silica concentrations ranged from 0.05 to 0.45 micrograms/m3 when sample values below the limit of quantification were treated as zeros. All of the long-term average concentrations were less than 20 percent of the Minnesota Department of Health’s and California Office of Environmental Health Hazard Assessment’s PM4 crystalline silica chronic reference exposure level of 3.0 micrograms/m3. The measured concentrations were consistently within the local background concentration range.Air Control Techniques P.C. compiled the sampling data using Thermo Fisher Scientific Inc. Partisol 2000i PM2.5 samplers meeting the requirements of 40 CFR Part 50, Appendix L. These samplers were adapted to capture particulate matter with a 50 percent cut size of 4 micrometers. The use of polyvinyl chloride filters allowed for crystalline silica X-ray diffraction analysis by NIOSH Method 7500. The combined use of adjusted PM2.5 filter-based samplers with Method 7500 crystalline silica analyses provided for a highly sensitive limit of quantification of 0.31 micrograms/m3 of PM4 crystalline silica.BackgroundIn 2005, the California Office of Environmental Health Hazard Assessment (OEHHA, 2005) adopted a 70-year chronic reference exposure level (REL) for PM4 (particulate matter having aerodynamic diameter of 4 micrometers or less) crystalline silica. The REL was extrapolated from occupational hygiene epidemiological studies, essentially all of which were based on in-plant PM4 crystalline silica measurements. No well-established ambient sampling technique for PM4 crystalline silica was available at the time that OEHHA adopted its REL. The personal samplers used for the National Institute for Occupational Safety and Health (NIOSH) Method 0600 in-plant sampling of employee exposure were designed for concentrations higher than ambient levels. The limit of quantification (LOQ) of PM4 crystalline silica on NIOSH 0600 filters was too high for the effective sampling of ambient air."

Jan 1, 2015

By Joseph M. Zigich

The Anaconda Minerals Company operates a molybdenite and copper producing mine and mill facility near Tonopah, Nevada. Included with the milling facility is a ferric chloride leach plant for removal of copper mineralization from the molybdenite concentrates. Discussed are the engineering and construction schedules associated with the leach plant. The chemistry associated with the process along with a description of the process flow, equipment, and operating parameters are contained in the paper.

Jan 1, 1983

By Y. Topkaya, R. E. Johnson, D. Buttinelli, B. R. Palmer, A. Geveci, L. Stoppa, C. Lupi, F. Pochetti

Representative samples of a composite mixture of three typical Cu/Zn complex sulphide ores, namely Black-, Yellow- and Altered-ore, from the Cayeli deposit in Turkey, were used for leaching tests in 2.2 M FeCl3, or 1 M CuC12-2 M NaCl solution in the temperature range from 313 K to 363 K (40O to 90O C), with and without the presence of an organic solvent for elemental sulphur, such as CCl4. The leaching rates of copper and zinc were quite high, as expected, in FeCl3 solution and complete recovery of both metals was obtained at the highest temperature when the solvent was present. However in CuC1, solution, extraction yields of the order of 95% only for Cu and Zn were achieved and the positive effect of the solvent was not clearly shown. The kinetics curves of Cu leaching by FeCl3 indicated a model of reaction rate depending on the particle surface, as in a chemically controlled reaction, in tests with the presence of CCl4. Without the solvent, or in CuCl2 media, the model of the diffusion controlled reaction seemed to prevail. Values of apparent activation energy, in both of the leaching processes, were determined and compared with those reported in literature.

Jan 1, 1993

By Jerry F. Fountain

Variations in ore grade, mineralogy, and copper pricing structures over the life of the Inspiration mine have mandated many modifications to the treatment methods to maximize process economics. In the 1970's, copper prices generally declined, while inflation, wages, and interest rates increased. A metallurgical treatment route had to be developed for this continuing economic climate which would be capable of minimizing labor, energy, and capital cost requirements. After many years of development, the patented "Ferric Cure" process was introduced to satisfy these requirements. This dump leach process for treatment of mixed oxide/sulfide ore includes: strict mineralogical control of ore placed for leaching, controlled leach pad construction, solution saturation and curing of the pads with higher acid concentrations, and, finally, rinsing of the cured pads for removal of dissolved copper. Leach solutions, high in sulfuric acid during the cure application and low in sulfuric acid during the rinse, contain sufficient ferric iron to enhance the leaching of chalcocitic sulfide minerals.

Jan 1, 1983

By Masanori Abe, Yoshitaka Kitamoto, Kazuhiro Nishimura

"Ferrite plating is a chemical processing which utilizes Fe2+ - Fe3+ oxidation to synthesizing polycrystalline films of ferromagnetic spinels (MFe20 4, M = Fe, Co, Ni, Zn, Al, Cr, TI, etc:) directly from an aqueous solution at 24 - 100°C. This low temperature process allows us to fabricate new ferrite film devices on · substrates of such non-heat-resistant materials as plastics, GaAs integrated circuits, and biomaterials. Synthesized from an aqueous solution the ferrite plated ·films are highly biocompatible. Thus various magnetic device and biomedical applications have been proposed and realized using ferrite-plated films. Ferrite-encapsulated polymer microspheres are applied to antibody carries for enzyme immunoassay, and also to toners/carriers for photocopying. Perpendicular magnetic recording media utilizing plated CoNi ferrite films are proposed. The low-temperature synthesized films of NiZn and Co ferrites are potentially used as soft-magnetic and/or insulating layers, respectively at high/microwave frequencies.IntroductionFerrite plating is a processing which facilitates the formation of crystalline spinel ferrite films with various compositions, (Fe, M)30 4 (M = Fe, Co, Ni, Zn, Al, Cr, TI, etc.), directly from an aqueous solution at 60 - 100°C [1]. This opened the door to fabricating novel ferrite-film devices using substrates of such non-heat-resistant materials as plastics and GaAs integrated circuits [2-4]; conventional ferrite film preparation techniques such as sputtering, vacuum evaporation, MBE, LPE, etc., require high temperatures(> -600°C) for crystallization of ferrites, which deteriorates the non-heat-resistant substrates. Recently we extended ferrite plating to be preformed at room temperature [5, 6]. This enables us to use as substrates such organic materials as biomaterials (e.g. enzymes) having very low heat-resistance."

Jan 1, 2000

By S Bright, M J. Masamvu, E K. Chiwandika, S Dandi, S M. Masuka

The depletion of high-grade hard and lumpy chrome ores has forced Zimbabwean ferrochrome producers to resort to low-grade friable ores that have an average of 28 per cent fines against a set limit of 12 per cent. Submerged open arc furnaces currently in use are associated with eruptions within the furnace because of the high amounts of fines, high energy consumption, as well as high SO2 and CO2 emissions. Traditionally employed agglomeration methods such as pelletising and the use of coke in the furnace have been discarded because of the pressure to lower operational costs and to achieve higher profit margins. This research aims to develop a method to incorporate lowgrade friable ore fines and unprocessed coal into production while lowering CO2 and SO2 emissions through a closed direct current (DC) arc furnace. The closed DC arc furnace could incorporate the friable ores and coal while maintaining above 90 per cent reduction rates. Preliminary findings also show that energy consumption could be reduced by up to 35 per cent by incorporating a pre-heating and pre-reduction system using the flue gases from the furnace. In the proposed circuit, the cost of production per ton of ferrochrome might be potentially lowered by an average of 30 per cent.

Jun 19, 2024

By R. G. Knickerbocker

A STURDY and consistent expansion of the metal industry occurred in 1947 exemplified by an increase of approximately 30 per cent in steel consumption over 1946. For this major reason, ferroalloy metals have seen their most useful and important peace-time year. The current domestic rate of consumption of high-grade ferroalloy ores, together with added consumption of new foreign producers as well as for eign nationals' restrictions on high-grade exports, makes very evident the increasing difficulties of obtaining sufficient high-grade ores. This accentuates the need for new and less expensive methods of production of ferro-alloy metals of higher purity from lower-grade domestic resources. As an important factor in preparedness, procurement of these high-grade, -critical ferroalloy minerals and metals for our nation's stock piles is a most important task. Also, this stock-piling can be the means of supplying incentive for the industrial development of the new metallurgical processes and plants necessary for the recovery of ferroalloy metals from our domestic low-grade deposits.

Jan 1, 1948

By P. R. Thomas

This paper addresses the relative long-term cost and resource position of new and existing ferrochromium production in selected Market Economy Countries (MEC'S). The market impact of new ferrochromium production in nations such as India and the Philippines and the continuing change in international trading patterns are also evaluated. This paper draws upon the data and analyses of a recent Bureau of Mines, Department of Interior, Minerals Availability Program appraisal that evaluated the cost and availability of chromite and ferrochromium production from the demonstrated resources of 80 producing or potential mining operations in 10 market economy countries.

Jan 1, 1984

By Yiling Zhang, Paul A. Salvador, Gregory S. Rohrer

"Photocatalysis utilizes solar energy to produce hydrogen by splitting H2O. When a thin film of photocatalyst TiO2 is supported on a ferroelectric BiFeO3 substrate (band gap ~2.5 eV), the TiO2/BiFeO3 heterostructure is capable of photochemically reducing Ag+ to Ag0 in aqueous solutions under blue light with enhanced efficiency. The observation of spatially selective silver patterns on surface of the heterostructure after reaction suggests that photogenerated electrons and holes in ferroelectric BiFeO3 are driven in opposite directions to reduce their chance of recombination. Comparisons of the amounts of reduced silver on TiO2 film grains with distinct phases/orientations show that the reactivity is mildly preferential on anatase TiO2 phase and does not strongly depend on crystallographic orientation of BiFeO3.IntroductionTitania (TiO2) is capable of photocatalytically converting H2O to hydrogen and oxygen under the irradiation of ultraviolet light. [1, 2] One of the limiting factors for titania to be used as an effective photocatalyst is its band gap. Because the absorption edges of rutile and anatase titania are at 3.0 eV and 3.2 eV, respectively, they can only absorb light in the UV portion of the spectrum, which is about 3% of the available solar energy. [3-5] This limitation has motivated attempts to modify the absorption edge of titania so that it can absorb visible light.One strategy is to substitute a portion of the titanium and/or the oxygen with other atoms. There are numerous reports on visible light absorption of titania by doping and co-doping of Cr, V, Mo, Sb, Fe, N, S, C, and F. [6-34] Another strategy is to add an adsorbed molecular species that absorb visible light and donate an electron or hole to the titania, such as organic dyes [33, 35, 36] and Ce3+/Ce4+. [37, 38]The strategy in the present work takes the approach of depositing a pure titania thin film on a visible light absorbing substrate BiFeO3 to induce visible light activity of the heterostructure. BiFeO3 is a semiconductor with a band gap of about 2.5 eV [39-41] and is photocatalytically active in visible light. [42, 43] It is also ferroelectric with spontaneous polarization along pseudo-cubic <111> directions of 6.1 µC cm-2. [44] The spontaneous polarization gives rise to internal electric fields that drive photogenerated charge carriers, namely electrons and holes, in opposite directions to reduce their chance of recombination. [45-47] Additionally, the separation of electrons and holes leads to the spatial separation of reduction and oxidation half reactions so that the back reaction of intermediates is also suppressed. Such charge carrier separation has been reported in TiO2/BaTiO3 heterostructures with UV light illumination. [48-51] The TiO2/BiFeO3 heterostructures in this work combine both advantages of the relatively narrow band gap and the internal fields in BiFeO3 to enhance the overall photocatalytic activity."

Jan 1, 2014

By Natalia Konstantinova, Georgy Novikov, Pavel Rekant, Goergy Cherkashov, Olga Bogdanova

The economic interest of oceanic ferromanganese crusts and nodules is determined by high grades of major, rare and earth rare elements in these types of marine minerals [1]. Modern oceanic ferromanganese deposits have a global distribution with the largest fields in the Pacific Ocean. The Arctic Ocean still remains a poorly explored region. The first ferromanganese deposits from the deep part of the Arctic Ocean were recovered almost at the same time in 2012 both in US and Russian cruises to the Chukchi Borderland (1) and Mendeleev Ridge (2). Preliminary results of mineral deposits from the first area were reported at UMI-2012 by James Hein et al. [2]. We present here the data of ferromanganese deposits from the Mendeleev Ridge.

Sep 1, 2014

By Alton G. Woody

Like so many installations of its type approaching middle age, the ore processing and shipping facilities in Puerto Ordaz, Venezuela, have taken a lot of twists and turns in their lifetime. The object of this paper is to lead you through these twists and turns and some of the reasoning for them. The need for additional sources of iron are in the United States became evident during the time of the second world war. An exploration team from U. S. Steel located further high quality direct shipping iron are in commercial quantities near Ciudad Bolivar, Venezuela in 1947. Basic decisions were made to develop these reserves for export via the Orinoco River through a new shipping port to be built at the confluence of the Orinoco and Caroni Rivers. The basic concept was for the ore to be loaded directly to ocean going vessels. This was something of a gamble since the basic economics depended upon successfully opening up the main channel of the Orinoco River to deepwater vessels, and the Bethlehem Steel mine in the same area was already working with shallow draft river boats and a transfer station on the coast. Always, the basic philosophy has tended to be to plan with expansion in mind. The original conveyor systems were 1.52 m (60 inches) wide with 200 idlers, whereas 1.07 m (42 inches) or 1.22 m (48 inches) wide conveyors could have carried any production foreseen at the time of installation. Stockpiles have been located and designed with room for expansion. Basic designs have had dotted line future expansion blocked in.

Jan 1, 1978

By André Mans, Frans B. Waanders

Current losses of Ferrosilicon (Fe-Si), which is used in the dense medium separation (DMS) of iron ore at Kumba Resources, Sishen, South Africa occur due to adhesion to the separation products and also by being present in the effluent stream, due to abrasion. The losses contribute greatly to the running cost of the plant and the purpose of this project was to determine the characteristics of the unused Fe-Si and then to characterise the changes that occur during storage and the use thereof. A Scanning Electron Microscope (SEM) and Mössbauer Spectroscopy (MS) were used to investigate the characteristics of the fresh and used Fe-Si. It was found that the biggest loss of Fe-Si was due to the abrasion of the particles during the DMS process, which resulted in the liberation of Fe and subsequent formation of an oxihydroxide froth. A possible change in magnetic properties was also observed, leading to further losses that could occur during prolonged use of the medium. No clear changes to the Fe-Si occurred during correct storage methods, as was initially thought.

Jan 1, 2003

By Roy W. Wright

Introduction The title of my paper is satisfyingly broad and allows me to touch lightly or dwell at length on virtually any aspect of mining, while endeavouring not to trespass on the subjects of other papers to be presented. However, at this stage in our world history when for the first time we are beginning to take conservation and the welfare of future generations more seriously, I want to concentrate mainly on the question of whether or not there will be the resources of minerals available to sustain mankind&apos;s progress in the generations ahead. Metals and the Population Problem The supply of raw materials is of course only one of the fundamental problems that will face future generations: if we assumed that the world population would continue to increase at the present explosive rate, then I believe we can say with certainty that other fundamental problems of much greater significance would arise long before a shortage of raw materials - or other substitutes -had any impact on the progress of mankind. Thus, I must start this paper with the assumption that some equilibrium in population will be arrived at before these other problems overwhelm the world. Will the Metals Run Out? At the 75th Anniversary Meeting of this Institute in March, 1947, Clinton H. Crane, President of St. Joseph Lead Co., prophesied that for the next 100 years there would be enough copper, lead and zinc for every essential need. He defined a need as essential where the qualities of the metal in that use were irreplaceable. Today, except for one or two cases such as lead in lead-acid batteries, few metals have qualities that cannot be provided either by another metal or by another material. It is more a question of what the engineer or manufacturer is prepared to pay for special qualities as compared with using cheaper materials and perhaps a less satisfactory design.

Jan 1, 1971

By Akira Yazawa

The composition of ferrous calcium silicate slag is located on the tie line between FeOx and calcium silicates in ternary FeOx-SiO2-CaO system. This slag has never been used as copper smelting slag because of high sulfidic copper solubility. However, when the dissolved copper in slag is just oxidic, as in direct white metal production or in converting process, this slag is quite attractive and can be regarded as the third copper smelting slag after fayalite and calcium ferrite slags. Based on the authors&apos; studies on phase separation thermodynamics and laboratory experiments, it was clarified that the oxidic copper loss in this ferrous calcium silicate slag become the minimum not only %Cu in slag but also the total copper loss when the amount of slag is taken into account. It has been proven that calcium ferrite slag is suitable for continuous converting where the dissolved copper is oxidic, but there exist some drawbacks such as limited solubility of silica, low lead removability and too high fluidity. To overcome these difficulties accompanying traditional slags, ferrous calcium silicate slag is the hopeful alternative. In view of the general trends of modem copper smelting processes, the interesting features of this new slag system are discussed.

Jan 1, 1999

By Asmo Vartiainen

Background of Direct-to-Blister Flash Smelting is discussed; especially slag chemistry relating to copper solubility, slag fluidity and impurity behavior. In December, 2000, Mini-pilot Flash Smelting test runs were carried out at Outokumpu Research Oy to produce blister copper from Chilean concentrate and white metal and from a mixture of them. Tested slag types were iron silicate slag, ferrous calcium silicate slag and calcium ferrite slag with different slag compositions and different concentrate/white metal ratios. The test runs were successful. The fluxing effect of copper oxide was clearly demonstrated and ferrous calcium silicate slags remained fluid on a very wide liquidus range. The distribution of arsenic between ferrous calcium silicate slag and blister copper is much higher than between iron silicate slag and blister copper. This successful test run with the new slag type offer new possibilities in Direct-to-Blister process design.

Jan 1, 2003

By Asmo Vartiainen

Background of Direct-to-Blister Flash Smelting is discussed; especially slag chemistry relating to copper solubility, slag fluidity and impurity behavior. In December, 2000, Mini-pilot Flash Smelting test runs were carried out at Outokumpu Research Oy to produce blister copper from Chilean concentrate and white metal and from a mixture of them. Tested slag types were iron silicate slag, ferrous calcium silicate slag and calcium ferrite slag with different slag compositions and different concentrate/white metal ratios. The test runs were successful. The fluxing effect of copper oxide was clearly demonstrated and ferrous calcium silicate slags remained fluid on a very wide liquidus range. The distribution of arsenic between ferrous calcium silicate slag and blister copper is much higher than between iron silicate slag and blister copper. This successful test run with the new slag type offer new possibilities in Direct- to-Blister process design.

Jan 1, 2003