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By L. Cui

A new flotation collector, benzyl arsonic acid, was used for the flotation of ilmenite. ESCA, Auger spectroscopy, and chemical analysis were used to investigate the correlation between the variation in surface constituents and the flotation recovery of ilmenite. Experiments indicated that, as the ratio of surface Ti ions/surface Fe ions increases, flotation recovery increases. pH regulation with an inorganic acid was found to be effective in changing the ratio of surface ions, and, hence, the flotation recovery.

Jan 1, 1986

By Carlini G, Ibba R

The KSS Lead Plant (Kivcet - SNAMPROGETTI - SAMIM) of Por tovesme, owned by Nuova Samim (the sector-head Company for non ferrous metals and derivatives owned by ENI), has been operating since february 1987. This plant is based on the Soviet Kivcet licence and testwork carried out on the pilot plant of VNIITSVETMET in Ust Kameno gorsk fed by the Nuova Samim's concentrates. The plant is com pletely automatized using the most advanced technologies and it is operated by nineteen people on shift work, including all ancillary units and lead decopperizing-casting. The expected performance of the plant has been confirmed and improves day by day in relation of the operating experience, thanks to the new conceptual design of the furnace. Due to the remarkable flexi bility of the process, the integration of the lead plant with the other plants of the metallurgical complex of Portovesme rro-#4 (Electrolytic Zinc Plant, Sulphuric Acid Plant, Imperial Smel ting) has shown all the economic advantages. The lead content in the ambient air, detected by the monitors, either in the working area and on the ground outside the complex, is widely Pb W" below the stricter new limits recommanded by the E.E.C. (Economic European Community) rules and by the Italian law. The whole process is carried out in equipment completely closed and under suction and it does not require manual operations with exposure to the lead. The production cost is much lower than that performed by the traditional technology. This advantage permits wide margin to consider investment to replace the traditional technology.

Jan 1, 1989

By T. Sterry Hunt

THERE are about sixty bodies which chemists call elements ; the simplest forms of matter which they have been able to extract from the rocky crust of our earth, its waters, and its atmosphere. These substances are distributed in very unequal quantities, and in very different manners. As regards the frequency of these elements in nature, neglecting for the present those which constitute air and water, and confining ourselves to the solid matters of the earth's crust, there are a few which are exceedingly abundant, making up nine-tenths, if not ninety-five hundredths, of the rocks so far as known to us. The elements of which silica, alumina, lime, magnesia, potash, and soda are oxides, are very common, and occur almost everywhere. There are others which are much rarer, being found in comparatively small quantities. Many of these rarer elements are, however, of great importance in the economy of nature. Such are the common metals and other substances used in the arts, which occur in nature in quantities relatively very minute, but which have been collected by various agencies, and thus made available for the wants of man. It is chiefly of the well-known metals, iron, copper, silver, and gold, that I propose to speak to-night; but there are two other elements not classed among the metals, which I shall notice for the reason that their history is extremely important, and will, moreover, enable us to comprehend more clearly some points in that of the metals themselves. I speak of phosphorus and iodine. You all know the essential part which the former of these, com- * An address before the Polytechnic Association of the American Institute, during the meeting of the American Institute of Mining Engineers in New York. Printed in this volume by request of many members.

Jan 1, 1873

By V. A. James

The new electrolytic copper refinery situated at Copper Cliff, Ontario, has been in operation for over a year and a half. This plant is operated by the Ontario Refining Company, Limited. The associated companies behind the enterprise are the International Nickel ?company of Canada, Limited, the American Metals Company, Consolidated Mining and Smelting Company of Canada, Limited, and Ventures, Limited. The plant was an outgrowth of the rapid development of copper resources in the nickel-copper ores of the Frood and other great mines in the Sudbury district, and of the desire to have all primary production units grouped together as compactly as possible. Starting anode furnace operations in June, 1930, and electrolytic refining on July 1st of that year, after a record-breaking construction programme completed in only fifteen months, the plant soon settled into its stride and the usual starting-up difficulties were .rapidly overcome. The rated capacity of the plant, namely, twenty million pounds of refined copper per month, has, of course, never been reached, due to depressed business conditions and latterly to the world copper agreement limiting production. It may be said, however, that the present installation has proved its ability to produce in excess of its rated capacity, and with relatively minor additions to plant and equipment that capacity can be doubled. Owing to the severity of the winters, when temperatures of from 20 to 40 degrees below zero are to be expected, the building of this refinery involved a number of problems in insulation, layout, ventilation, etc., which were rather unusual in copper-refinery construction.

Jan 1, 1932

By Zhihe Dou, Yan Li, Qiuyue Zhao, Guozhi Lv, Yan Liu, Hongliang Zhao

"Abstract: How to reduce carbon dioxide emissions has become a vexing problem, meanwhile, there exist high energy consumption and low efficiency problems in the existing CO2 capture and storage technologies. For CO2 comprehensive Utilization, this paper researches a new technology of absorbing the CO2 emission with high alkaline calcium or high alkaline wastewater sludge mineralization of calcium and invent a core device for multi-level jet carbonation. The industrial test has been carried out in China Xinyu slag Engineering Co., Ltd. The wastewater flow is 150m3/h in the pilot scale. The prepared calcium carbonate has a whiteness greater than 90%, particle size less than 150nm. The mineralization of aluminum exhaust with waste carbide indicates that the CO2 absorption rate is greater than 99.0%, CO2 concentration in the exhaust gas is lower than 0.08%, the purity of mineralized calcium carbonate is greater than 99.0% and particle size is less than 100 nm.InstructionAccording to the statistic data from IEA (2009), the carbon dioxide discharge from fossil fuel consumption in China has exceeded it in the US by the year of 2007, China, has become the largest emitter of carbon dioxide all over the world. Meanwhile, the economic scale is still on an increasing trend in the next 50-100 years, leading to a continuous increment in carbon dioxide discharge. According to the international energy agency forecasts, the energy-relative CO2 discharge in China will rise to 11,615 million tons, 91.3% higher than it in 2007. In the year of 2012, the CO2 gross discharge has reached 10,000 million tons, obviously higher than the predicted value. It is a tremendous task to reduce the emission. Non-ferrous metals industry is one of the largest emitters of carbon dioxide among the industrial circle, the whole industry might discharge a huge amount of carbon dioxide (over 600 million tons), in which the electrolytic aluminum industry is the largest energy consuming industry and CO2 emitter. At present, the CO2 discharge has focused by the whole world due to the environmental problems it causes; meanwhile, supplement of new carbon source is needed due to the exhausting oil and coal resources, so that various countries in the world are attaching importance of the recycle and purification of CO2. Many countries are studying on the cyclic utilization of carbon dioxide. Gas CO2 is mainly applied in chemical, pharmaceutical raw materials, beverage filling agent, refrigerant, inert medium, solvents, pressure source, the welding protective gas, antioxidant and fire extinguishing agent, etc. Solid CO2 is mainly applied in penicillin production, fish, cream, ice cream and other food storage and transportation at low temperature, etc. nowadays, such methods as absorption method, membrane separation, adsorption, etc. are widely used to recycle CO2, with such problems as high investment cost and technical constraints etc."

Jan 1, 2014

By Anthony J. Peach

With the new generation of so called "Super TBM", we would all expect to witness the implied super-performance. In some instances this is occurring, but one must ask why is it not occurring in the majority of applications? For hard rock TBM related projects, we are observing a decrease in the volume of projects in the previously traditional areas such as North America and Western Europe and an increase in Asia (Hong Kong, Indonesia, China, Korea etc). As a consequence less experienced contractors are acquiring the latest ultra high power equipment, without the knowledge necessary to achieve optimum performance. The interdependence of TBM and muck removal systems has been assessed with emphasis on the emergence of the continuously extending conveyor technology, as a means of achieving dramatic productivity increases. The Australian system assessed here at the time of drafting this paper holds the world record tunnel excavation production of 2,166 metres. A little considered aspect of the adoption of conveyors is the associated improvement in safety.

Jan 1, 1995

By T. Takayama Filho

Votorantim Metais Zinco is a smelting facility which produces SHG zinc, zinc alloys, sulfuric acid, liquid SO2, copper sulfate, cadmium metal and silver concentrate. It is located at Juiz de Fora, Minas Gerais State, Brazil. This facility has been operating since 1980 and its current capacity is 95,000 tonnes of zinc per year, using mostly imported sulfide concentrates.The plant uses the conventional roast-leach electrowinning (RLE) process, in which iron is removed from the circuit as jarosite. The residues generated by the RLE process, which amount to about 200 t/day (dry weight), were until 10 years ago, deposited in tailing ponds having no impervious lining. More recently, jarosite and other wastes have been deposited in a properly built reservoir, but this is reaching its maximum capacity. In order to decommission these disposal operations and to reclaim the sites in an environmentally acceptable manner, Votorantim Metais concluded in 2004 a rehabilitation project for the old tailings pond and prepared detailed plans for managing the current and future disposal of jarosite-bearing residues. This paper describes the procedure for removing iron from the hydrometallurgical circuit and discusses the past and current status of the residue disposal sites, as well as the future challenges related to the environmentally acceptable handling of iron residues.

Jan 1, 2006

By L. Zhang, Y. Zhou, H. Wang, C. Mo

Fluorination of magnetite (Fe₃O₄) by NH₄HF₂ was investigated using simultaneous thermogravimetry and differential thermal analysis (TG-DTA), and observing the morphology and phase changes using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray diffractometry (XRD). The results indicate that fluorination with the involvement of oxygen begins at room temperature, peaks at 178.40C, and is completed at 2000C with the formation of only (NH₄)₃FeF₆. On heating, (NH₄)₃FeF₆ gradually releases NH₄F by the formation of NH₄FeF₄ at 2590C, then (NH₄)0.18FeF₃ at 3270C, and finally FeF₃ with minor FeF₂ at 4000C due to the partial reduction of Fe (III) to Fe (II). At 5500C, FeF₃ is oxidized to FeOF/Fe₂O₃.

Dec 13, 2022

By M. O. Pekguleryuz, D. S. Aydin

The high temperature oxidation and ignition resistance of Mg-(0-6) wt% Nd alloys have been investigated via isothermal and continuous heating experiments conducted in air atmosphere. Alloy composition is observed to be effective in low levels (~ 0.5 %) in the ignition temperature (Ti) of the alloys; the Ti of pure Mg increased from 630 °C to 770 °C with 0.5 wt% Nd addition. However, no noteworthy improvement was achieved with further additions up to 6 wt% Nd. The initial microstructure was observed to determine the oxide structure on the surface due to the differing oxidation behavior of the phases (a-Mg + Mg12Nd intermetallics). It has been found that the formation of a Nd-depleted region at the subsurface due to extensive Nd oxidation at the oxide/intermetallic interface lowers the protective ability of the oxide scale.

Jan 1, 2015

By M. M. Kulkarni1

Kaolin clay is used as a filler and pigment in various applications such as paper, paint, rubber, plastics, adhesives, ink and ceramics etc. Major mineral content in crude kaolin clay is kaolinite along with some accessory minerals as quartz, hematite, mica, feldspar, anatase, rutile, illemnite etc. The Fe and Ti bearing minerals play very important role in determining quality of the kaolin, as these minerals impart yellow, pink or darker color to the white kaolin. Conventional beneficiation methods used in kaolin processing are de-gritting, classification and sodium dithionite bleaching, which improves the optical properties of kaolin, wherein reduction of color imparting constituents such as Fe2O3 and TiO2 is marginal. In the present study, these coloring impurities are separated using selective adsorption of water-soluble polymers. Degritted kaolin samples after passing through 45 micron sieve is used in the study for selective flocculation by polyacrylamide based polymers. The effect of pH, zeta potential, and polymer dose on the reduction of impurities is studied. Analytical tools such as XRF, XRD, SEM, and TEM techniques are utilized and results are discussed in detail.

Sep 1, 2012

By Jheison Lopes dos Santos

O presente estudo teve por objetivo principal produzir um cerâmico composto de alumina, nióbia e fluoreto de lítio de forma a otimizar o uso do forno na etapa de sinterização. Para isso, ponderou-se a respeito da necessidade ou não de utilização de um patamar a 1000°C utilizado em estudos anteriores. Além disso, buscou-se diminuir a temperatura de sinterização, assim como o tempo de permanência em tais temperaturas. O composto cerâmico (Al2O3–4%Nb2O5)–0,5%LiF foi sinterizado a três temperaturas diferentes (1200, 1250 e 1300 ºC), com tempo de patamar de 1h. Foi realizado ensaio de Arquimedes para analisar sua densificação e determinar sua densidade. As fases formadas nessas temperaturas foram identificadas por difração de raios-X. Os resultados mostraram que a maior densificação foi obtida para a maior temperatura, de 1300 ºC. Foi possível observar também que um patamar de apenas 1h na temperatura de sinterização de 1300 ºC apresentou igual densificação a de outros trabalhos, com tempo de patamar de 3h. Este fato sugere que a temperatura tem maior influência na sinterização do que o tempo de permanência. Verificou-se ainda que as mesmas fases foram formadas nas três temperaturas investigadas, sendo tais fases as mesmas detectadas em trabalhos anteriores com patamares maiores. Isso mostra que o prolongado tempo de 3h no patamar de sinterização apenas favorece o crescimento dos grãos, bastando apenas a permanência de 1h para alcançar os resultados desejados e com grãos menores.

Oct 30, 2017

By M. J. Ferrante

Relative enthalpies of high-purity disodium hexatitanate (Na2Ti6013) were measured at the Bureau of Mines to provide new thermodynamic data needed to advance the technology of materials. Measurements from 298.15 to 1,478 K were made by drop calorimetry with a copper block. Tabulated values are listed for the standard relative enthalpy, heat capacity, en-tropy, and Gibbs energy function between 298.15 and 1,500 K. Enthalpy data are also given in equation form and are combined with thermodynamic data from the literature to derive values of standard enthalpies of formation, Gibbs energies of formation, and logarithms of the equilibrium constants of formation. Similar calculations were made for the reaction of Na20 with Ti02.

Jan 1, 1986

By P. Bevilacqua

In this paper the possibility to complete the copper recovery and to enrich in PVC a mixture of plastic granules obtained by grinding electrical cables are investigated. The recovery of a large part of the copper still present among the plastic granules was possible by means of a mechanical screening, the finer polymeric fraction was collected, at the same time. In order to complete the copper polymer separation the following techniques were employed. Counter current separation in water, static dense medium separation with zinc chloride solution and copper extraction with nitric acid and subsequent electrolytic deposition. A Tri-Flo® dynamic dense medium separator was employed in order to separate the lighter polymeric fraction, from the heavier polymeric fraction, mainly PVC. Water or a salt-water solution was employed to feed the separator device.

Jan 1, 2014

By W. J. Spat

Political risk is an integral part of the mining business in Northern Andean countries. Peru, Ecuador, Colombia, and Venezuela all have a higher than average political risk compared with other South American countries. Successful operations in such contexts require: 1. Good political risk information; 2. A thoroughgoing political risk management plan; and 3. A strategy to deal with political risk perception on the part of the investing public. Obtaining quality political risk information, developing a political risk management plan, and addressing political risk perception are the foci of this work.

Jan 1, 1999

By R. C. Gabler

Effective recycling or disposal of flue dusts is a continuing problem, particularly for secondary smelters treating low-grade Cu scrap. The Bureau of Mines investigated a variety of flue dust treatment approaches and demonstrated the technical feasibility of a bench-scale alkaline method that includes leaching, cementation, precipitation, and roasting. Flue dust was leached at room temperature with an alkaline solution of (NH4)2C03 and NHpH to solubilize ZnO and Zn metal. Some copper, lead, tin, and most of the zinc were dissolved in the leach step. Copper, lead, and tin were recovered in the cement product. The Zn in the flltrate was precipitated by pH adjustment to neutral using CO2 injection. The Zn salt was flltered from solution and roasted to give high-purity ZnO. The leach residue, enriched from 4.3 to lOA pct Sn, could find a ready market; the metallic cement product can be recycled back to the copper converter; and the high-purity ZnO product can be sold in several markets, leaving no material for disposal. The possibility for recycling of reagents, lower energy demand, and low environmental impact make this method economically and environmentally attractive for recycling secondary copper smelter flue dusts.

Jan 1, 1988

By G. Coetzer

"Prior to operating a non-recovery coke pilot plant, it was critical to ascertain coal cake stability during the loading of a 1 m3 coal cake into the oven. Various compaction parameters were verified and established on a small laboratory-scale compaction machine to obtain a coal cake of acceptable stability. These parameters include cake density, cake surface moisture, transverse strength (force applied perpendicular to the original compacted coal cake layers), and applied force to the coal cake. This work determined the behavioural characteristics of the coal while being compacted either with a full-sized or a 1/3-sized compaction plate in a 9 kg capacity mould. Two different coals were evaluated, namely Waterberg semi-soft coking coal (sscc) and Oaky North hard coking coal.The target wet cake density of 1 100 kg/m3 (79% of 1 400 kg/m3 relative density) was achieved for Waterberg sscc, with a particle size d50 varying between 0.6 mm and 1 mm, utilizing the 1/3-sized compaction plate in the laboratory-scale set-up, with 11.6% surface moisture and 92.2 t/m2 commercial equivalent applied force. For Oaky North hard coking coal, a wet cake density of 1 189 kg/m3 (85% of 1 400 kg/m3 relative density) was achieved at a surface moisture content of 12.3% and at a lower applied force than that for Waterberg sscc, i.e. 78.5 t/m2.Coal cakes of acceptable strength, and therefore sufficient stability for further processing, were obtained for all materials evaluated during this study.Further studies should be conducted to determine the effect of zeta potential during the compaction of coals.IntroductionExxaro Resources has successfully installed and commissioned a world-class stamp-charging horizontal 1 t electrically-heated pilot-scale coke oven at its Metallurgy Services facility. Prior to operating the coke non-recovery pilot plant, it is essential to ascertain coal cake stability during the loading of a 1 m3 coal cake into the oven. The design of Exxaro’s pilot plant is such that the coal cake is pushed inside the oven by means of a pusher plate, rather than through a ‘spoon’ feed mechanism, such as is found in industrial horizontal coke ovens. The pusher plate loading mechanism dictates that the coal cake should possess high stability and inherent strength during loading into the oven, owing to frictional forces exerted by the oven floor. In order to obtain a coal cake of acceptable stability, various compaction parameters needed to be verified and established on a small laboratory-scale compaction machine."

Apr 1, 2019

By Wm. Snow, J. R. Wallace, E. P. Duchemin

"GeneralA NOT INCONSIDERABLE proportion of the Canadian economy is dependent on the coal mining industry. This is particularly true of the eastern portion of Canada and especially so of the ( authors') province of Nova Scotia. Much has been said about the trying economic straits of the coal industry in Nova Scotia ( 1), faced, as it is, with difficult mining problems, with considerable distance from large markets, and with •competition from other (and usually foreign) fuels. It is of particular interest, at this time, therefore, to discuss one of the larger outlets for coal -that of the production of metallurgical coke.Scope of PaperWhile the title of this paper indicates that it deals with Metallurgical Coke in Canada, the authors beg leave to treat the Canadian industry very briefly and to deal specifically with coal, •coke, and smelting problems with which they are familiar, namely, the operation of the Dominion Steel and Coal Corporation in the Sydney, N.S., area. No mention is made of metallurgical coke for use in the •many foundries in Canada or in the non-ferrons metallurgical industries.Coal and Coke StatisticsA few statistics of the total output of .Canadian coal, production of metallurgical coke, and similar figures for the Dosco holdings (Sydney area only) are shown in Table I."

Jan 1, 1955

By K. A. du Preez, P. J. van Staden, M. van Rooyen

Mine-impacted water, including acid mine drainage (AMD), is a global problem. While precipitation of dissolved metals and neutralization of acidity from mine-impacted water is accomplished relatively easily with lime addition, removal of sulphate to permissible discharge limits is challenging. This paper presents a high-level comparison of four sulphate removal technologies, namely reverse osmosis, ettringite precipitation, barium carbonate addition, and biological sulphate reduction. Primarily operating costs, based on reagent and utility consumptions, are compared. Each process is shown to be subject to a unique set of constraints which might favour one over another for a specific combination of location and AMD composition. Access to and cost of reagents would be a key cost component to any of the processes studied. The total cost calculated for each process also depends on the type of effluents that are allowed to be discharged.

Oct 1, 2021

NEW MEMBERS The following list comprises the names of those persons who became members during the period Feb. 10, 1919, to Mar. 10, 1919. ALLEN, ROLLAND CRATEN State Geol., Appraiser of Mines, Lansing, Mich. ALTMAYER, MAURICE ERNEST, Ingenieur des Arts et Manufactures, 145 Rue de la Pompe, Paris, France. AUSTIN, CHARLES L., Assayer, Highland Boy Mine, Utah Cons. Min. Co., Bingham Canyon, Utah. BARTLETT, ARTHUR J., Chief Engr., Louisville Coal & Coke Co. Goodwill, W. Va. BOIES, ORLOW W., Research Chem., Roessler & Hasslacher Chemical Co., 1632 Tenth St., Niagara Falls, N. Y. BRAGG, G. A., Mgr., Experimental Copper Leaching Plant, Mellon Inst. of Industrial Research, Thompson, Nev. BRUSCANTINI, GIOVANNI, Min. Engr., Gen'l Mgr., Sindicato Minero de Cuba, Box 370, Santiago, Cuba. COLONY, R. J Instructor in Geol., Columbia University, New York, N. Y. DAVENPORT, FRANK B., Cons. Engr., 806 Coal Exchange Bldg., WiIkes-Barre, Pa. EATON, S. FORD 120 E. 85th St., New York, N. Y. EBY, J. H., Min. Engr Box 433, Spokane, Wash. ENGELHARDT, EDWARD A., Mgr., Surinaamsche Bauxite Mij, Paramaribo, Dutch Guiana, S. A.

Jan 4, 1919

By Norimasa Yamasaki, Masao Kurosaki

"The effects of plating conditions on the crystal orientation of electrodeposited zinc were investigated by varying elecyrolyte flow rate and current density. Precipitation of the Zn (00 • 2) basal plane is promoted at lower current density and higher flow velocity. Effect of the flow velocity on the mass transport was evaluated based on the polarization measurement in which Cu was used as the tracer. As a result, it has been clarified that the crystal orientation of electrodeposited zinc can be uniquely arranged by the overvoltage (iU0.5) that can be simply calculated by considering -the current density and boundary layer thickness. At the same time, the electrode potential during electrodeposition that can be calculated by using a model based on the competitive reactions of hydrogen reduction 'and zinc reduction exhibits an extremely good correlation with the crystal orientation of electrodeposited zinc.Introduction Electrogalvanized steel sheet has better surface properties than hot-dip galvanized steel sheet, and is used in home electric appliance and automobile applications. Factors such as crystal morphology, crystal orientation and surface roughness have a large influence on its appliance, formability and corrosion resistance [1-3].Electrolysis, condition, bath composition and alloying elements are reported as factors that affect the crystal orientation of the electrogalvanized coating. Factors that can be controlled on time in the production site are electrolysis condition that-is current density and plating solution flow velocity.Some studies[4-6] report that the crystal- orientation of the Zn(00 • 2) plane is increased by promoting, the mass transfer of zinc ions in the plating solution or decreasing the concentration overvoltage, but did not investigate in detail the plating solution flow conditions in the plating cell nor quantitatively determine the effects of both current density and plating solution flow conditions on the crystal orientation of ' electrodeposited zinc."

Jan 1, 2000