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By Walter D. Holland

LFE Environmental performed an Industrial Hygiene survey of the Paraho Oil Shale Mining and Processing facility in Anvil Points near Rifle, Colorado, on August 6 and 7, 1975. This survey consisted of an investigation of the underground operations for diesel emission contaminants and of the above ground work areas for all inhalation contaminants other than silica dust. Samples were collected to investigate the following contaminants: respirable dust, total dust, NO2, NO, H2SO4, formaldehyde, CO2, S02 and CO. None of the determinations of contaminants in the underground operations indicate air concentrations exceeding their standards. The results for the samples collected above ground indicate only one operation where the employee's exposure exceeds the standards. It is a welding operation where the standards for total dust and lead are exceeded. Since the survey the employer has installed an exhaust ventilation system which has significantly reduced the welder's exposure.

Jan 1, 1976

By R. H. Moore

The data for diffusion in dilute binary alloys with the Solvents Ag, Cu, Ni, Fe. Al. and Pb hare been correlated as a function of atomic volume. Linear equations of the form: Q = b - a log V are obtained with constants "a" and "b" ciuirac-teristic of each solvent metal. In most cases. 3-d In recent years measurements of diffusion coefficients in solid binary alloys. using small concentrations of radioactive isotopes. have resulted in accumulation of highly reproducible data. Such and 4-d transition elements correlate on separate straight lines from those which serve to correlate the non/ransition elements. The data for the uon-transilion elements diffusing in silver and copper liave been fitted by least-squares analysis. It is concluded that the size and charge effects which determine the magnitude of the activation energy for diffusion are a function of atomic volume. systems represent the simplest possible examples of chemical diffusion since solute interaction effects can be neglected and Kirkendall-like phenomena do not occur. Generally it is found that thc diffusion rate of the solute is within an order of magnitude of the diffusion rate of the solvent. The differences have been attributed to the effect of size and to electrostatic interactions between the solute and solvent atoms.

Jan 1, 1965

Goodenough and Fergusson Islands, in eastern PapuaNew Guinea, lie in an area of crustal extension on the western end of the Woodlark Basin seafloor spreading system. The islands are made up of a number of mountainous domes of complexely deformed basement, and these are intruded by large bodies of granodiorite. The domes are bounded by curved shear zones and faults dipping outwards at angles of around 25 to 45¦. The cores of the domes contain lower crustal rocks of eclogite and granulite facies, these rocks have undergone retrograde metamorphism in the outer sheared zones. Movement indicators on the shear zones indicate a complex moverm.-It geometry which does not fit the models proposed by earlier workers. These dome-like structures are similar to the metamorphic core complexes of the western United States Cordilleran region, however there are a number of aspects which do not fit with the models proposed for the development of metamorphic core complexes. Uplift of the metamorphic basement probably resulted from a combination of forces associated with the extension of the crust and the intrusion and emplacement of granodiorite plutons.

Jan 1, 1990

The 31st annual American Hall of Fame Awards Banquet and Fundraiser sponsored by the Mining Foundation of the Southwest (MFSW) will be held at the JW Marriott Tucson Starr Pass Resort on Saturday, Dec. 7, 2013. Each year, one living inductee, two Medal of Merit recipients, honorees from mining?s past, an industry partnership award, as well as a special citation, are recognized by the MFSW for their respective contributions to the mining industry. James D. Toole, past president and chief executive officer of Southwest Energy LLC, will be the Hall of Fame inductee, guest of honor, and featured speaker at the awards banquet. Toole founded Southwest Energy LLC in 1973 and is credited with introducing innovative explosive technology, providing even greater value to its mining customers. Medals of Merit will be awarded to Joseph M. Keane, principal metallurgical engineer for SGS Metcon Research/KD Engineering, and Sean D. Dessureault, associate professor at the University of Arizona. Keane is recognized for his metallurgical expertise, especially in design development and pollution abatement. Dessureault is recognized for his advanced mining research, with more than 25 journal publications, and his entrepreneurship as the founder and chief executive officer of two mineral-related companies. To honor mining?s past, the hall of fame will induct Bartolomé de Medina for his invention of the patio process for recovering silver; Ben Williams for his management of the Copper Queen Mine in Bisbee, AZ; Charles E. Mills for his contributions at Morenci and Inspiration Copper and founding Apache Powder Co. and The Valley National Bank; John S. Finlay and Edwin B. Royle for their invention of the mucking machine; and Louis Caryl Graton for his ore deposits research and teaching economic geology at Harvard University.

Nov 1, 2013

By A. V. Faiberg

Currently, the interest to conditioning of cyanide-bearing recycled solutions with high-grade of base metals, in particular, copper has significantly grown. This can be explained by two major factors. Firstly, there are strict regulations on cyanides amount in tails and higher cost of detoxification processes. This problem can be easily solved during the ore treatment using the conditioning of solutions and water recycling. Secondly, the presence of other metals minerals which react with cyanide during gold leaching resulting in high cyanide consumption. The presence of copper is a major problem. Many copper minerals react with cyanide with the formation of cyanide complexes-Cu(CN)2-, Cu(CN)32- and Cu(CN)43-. One mole of copper consumes 2-4 moles of free cyanide. Availability of cyanide-soluble copper minerals has deleterious effect on gold leaching (gold recovery, cyanide consumption, tails detoxification, efficiency of gold elution and electrowinning). The precipitation of copper from the solutions improves gold recovery by CIL. The removal and recycling of cyanide allowed the reduction of cyanide addition to the process. The recycling of spent cyanide-bearing solutions based on the removal of copper and the return of cyanide bound in complex compounds for leaching process is an optimal way of solving the problem of gold-bearing copper ores treatment. By using the technology, an adverse impact onto gold recovery process is eliminated and at the same time reducing the cyanide consumption. Today, processes and methods of high-grade copper leaching solutions conditioning before and after gold recovery have been developed, which combine two ways of copper recovery: as a saleable product and cyanide to recover gold and reduce total operating costs. They are Cutech, MNR, SART, Cyanomet, AuGment, Vitrokele, Hannah and Cyanisorb. At the same time, these technologies have not been studied enough and described in literature. Data on parameters and operating conditions as well as introduction is not available. The conditioning technology of recycled solutions developed by IRGIREDMET JSC allows copper to be recovered as high quality concentrate and at the same time free cyanide regeneration in the recycled solution which is amenable to gold leaching. This technology was commercialized at a mine in Kazakhstan in 2008. The removal and recycling of cyanide does not require additional cyanide and is cost-effective. More cost-efficiency is achievable through selling copper concentrates, closed water cycle without the detoxification of effluents and enhanced gold recovery by CIL and cathode quality.

Sep 1, 2012

By Ralph H. Nafziger

The Bureau of Mines, in cooperation with the Idaho National Engineering Laboratory, has electroslag melted a V-5Ti-5Cr alloy using a fused CaF2, flux. The alloy is a candidate for use in future fusion reactors. One objective of this research was to evaluate the feasibility of the electroslag melting process in separating simulated radioactive isotopes from the V alloy to demonstrate recyclability. Small amounts of Ca, Y, and Mn were added as surrogates for radioactive isotopes. Results showed that this vanadium alloy can be electroslag melted satisfactorily. The impurities added intentionally were removed or decreased successfully. Among the major alloying constituents, Cr was retained but there were some Ti losses. The latter may be controlled with process refinements. This research suggests that the electroslag melting process could be a suitable method for recycling V alloys after use in future fusion reactors, or for processing other reactive metal alloys with more immediate applications.

Jan 1, 1996

By M Akhtar, E Jak, M Shevchenko

This article presents an overview of the experimental phase equilibria studies of S-containing systems (Ni-Sn-S, Cu-Sb-S, and Cu-Sn-S) and As-containing systems (Fe-Sb-As and Fe-Sn-As). These systems improve the prediction capabilities of FactSage in a 20-component ‘Cu2O’-PbO-ZnOFeO- Fe2O3-CaO-SiO2-S-(Al2O3-MgO-CrO-Cr2O3-Na2O)-(As, Sn, Sb, Bi, Ag, Au, Ni, Co) system for complex pyrometallurgical operations during both refining and recycling. Experiments involved equilibration at predetermined temperatures (300–1200°C) with or without preheating, followed by rapid quenching in a brine. Quenched samples were then directly measured using an electron probe microanalyser. For the Ni-Sn-S system, liquid phases (NiS- and SnS-rich mattes and liquid metal) and solid phases (Ni1+xSn, SnS, Ni3Sn, FCC-Ni, Ni1-xS, NiS2, Ni3Sn4, SnS2, Sn2S3 and β-Ni3S2) were observed. A new Ni3Sn2S2 phase was found to melt incongruently. For the Cu-Sb-S system, liquid metal, matte, FCC-Cu, digenite, Sb, CuSbS2, Cu3SbS3 and Cu3SbS4 phases were observed. For the Cu-Sn-S system, liquid metal, matte, digenite, SnS and Cu3Sn phases were found at liquidus.

Jun 17, 2024

By Eduardo de Paula Silveira, Carlos Vinícius Domingos de Carvalho, Roberto Parreiras Tavares, André Afonso Nascimento, Honicássio de Souza Ferreira, Afrânio Márcio Costa

Modelos de transferência de calor possibilitam o conhecimento de espessura da camada solidificada e temperatura da placa, essenciais para alterações no processo visando melhoria de qualidade. Neste estudo foi desenvolvido um modelo pelo método 2½ D, que consiste em acompanhar em toda extensão da máquina uma secção transversal da placa, ajustando as condições de contorno para cada região. Medições de temperaturas superficiais e de espessura da camada de aço solidificada da placa foram utilizadas para validação do modelo. O modelo foi adequado para as condições de contorno e parâmetros da máquina de lingotamento contínuo de placas da Gerdau Ouro Branco visando fornecer subsídios para a melhoria da qualidade superficial e interna das placas.

Oct 1, 2019

By Jose Bengoa

Low metal prices and environmental restrictions are always a challenge for copper smelters operation and its productivity. Thus, in order to reduce production costs and control gas emissions, improvements of the Teniente Converter (CT) operation were made at 110 Smelter Plant of Southern Peru Copper Co., 110, Peru, and the main objective was to increase its capacity for smelting copper concentrates without affecting normal operation. The present work corresponds to a recent study conducted during the normal industrial operation of the Teniente Converter in this plant and, it shows the effect of increasing air oxygen enrichment from 28 to 34% on its productivity. The results show an increasing of concentrate smelting rate from 800 to 1370 tpd and hence a notorious improving in copper production, and practically no effect on the refractory consumption. The increment of the concentrate throughput, increases also the SO2 concentration and the sulfuric acid production, showing the effort done by this operation in order to accomplish the environmental Peruvian regulation.

Jan 1, 2003

By Manuel Cabrera Melendez

Actualmente las explotaciones en la pequeña minería producen exclusivamente minerales de alta ley puesto que cubre el costo de los fletes y las maquilas, dejando de lado los minerales de alta ley. En esta perspectiva, el texto plantea una alternativa técnica y económica que mejore las condiciones anteriormente planteadas a partir del uso del carbón activado para así beneficiar los yacimientos de baja ley y optimizar el desarrollo minero aurífero de nuestro país. Así también la tecnología del carbón activado reduce los costos de operación puesto que se da una versatilidad del tratamiento de minerales, genera mayor recuperación del oro y mejora su productividad.

Nov 24, 1986

By H. EI-shall

Bench top centrifuge is used to study the consolidation behavior of phosphatic clays. A mathematical model (based on first order kinetics) is developed to describe the relationship between the void ratio (at any time) and the effective stress. Permeability of the sediment as a function of the void ratio is also described. The obtained data are compared with that obtained by other consolidation testing methods. Centrifuge results indicate that consolidation data may be developed in a short period of time (hours) as compared to days or weeks when other techniques are used.

Jan 1, 1995

By S. J. Pearce

There are a number of methods for determining relatively small quantities of sulfur dioxide in air. However, those methods require fairly elaborate apparatus and laboratory facilities. Frequently in industrial hygiene surveys it is desirable to have a simple arrangement to obtain "on the spot" determinations. This has been accomplished for concentrations of sulfur dioxide of hygienic significance by using the midget impinger and decolorizing a starch-iodine solution.

Jan 1, 1948

By B. R. Mohal, F. F. Aplan, S. Chander

"The wetting behavior of coal has been determined in the presence of nonyl and octyl series of nonionic surfactants containing polyethoxy groups of different sizes. The wetting behavior was determined by a modified Walker technique and contact angle measurements. The results show that the wetting rate of coal varies with coal rank, structure of the hydrocarbon chain and number of ethoxy groups in the hydrophilic group of the surfactant. A close relationship has been observed between the wetting rates and the short-time advancing contact angles.INTRODUCTIONNonionic surfactants are used in many applications to improve wettability of solids. They can be used as dispersing agents [ 1 ] or dust suppressants [ 2-5] and to control the flotation, flocculation, filtration and, flowability of particulates. This study was undertaken to study the effect of a series of nonionic surfactants on the wetting behavior of coal. Two series of surfactants, namely, ethoxylated nonyl and octyl phenols were used. The nonyl phenol series con tains a linear hydrocarbon chain containing nine carbon atoms (CH3 ( CH2 )8-C6H4- ( OC2H4 ) n, where n is the number of ethoxy groups) . The octyl phenol series contains a branched hydrocarbon chain containing eight' carbon atoms ( ( CH3 ) 3CCH2C ( CH3) 2-C6H4- ( OC2H4 ) n ).Initial wetting rates — modified Walker techniqueWalker et al. [ 6 ] developed a sink test to determine the wettability of coal particles. In this technique, coal particles are dropped individually onto the surface of surfactant solutions of different concentrations, and the most dilute concentration in which coal would sink ""instantaneously"" is determine& This technique is a variation of a procedure initially developed by Draves and Clarkson [ 7 ] to determine the effect of surfactants on wettability of cotton fibers."

Jan 1, 1989

By Dave J. Porter

Si bien, los proyectos son el camino para que una organización minera cumpla con su estrategia, la gran mayoría de su historial de cumplimientos son un fracaso puesto que el impacto del proyecto no es tan rico en sus etapas y las organizaciones mineras no pueden cumplir con su visión y estrategía. En ese sentido, el presente texto señala la importancia de una adecuada gestión de proyectos para que la organización minera cumpla con su estrategia. Así, la madurez de la gestión de proyectos es un indicador de éxito continuo y requiere de visión, compromiso en las etapas iniciales, ya que sus ganancias son difíciles de cuantificar.

Apr 1, 2012

The coal resources of the Singleton- Muswellbrook area of New South Wales are of major importance to Australia, and are likely to play a significant role in meeting the expanding demands for energy in many countries of the world. Coal resources of 45 thousand million tonnes of which 15 thousand million tonnes lie at a depth of less than 200m have been estimated. The history of coal mining in the area commenced in the mid 1800's and has been one of fluctuations in production but of rapid expansion in more recent years. It is destined to become the largest coal producing area in New South Wales. Coal is being won from the area by strip mining, open pit mining and by underground means. The techniques involved are described. The area is well endowed with infra- structure such as modern towns, railways, road- ways and access to port facilities. Production of both coking coal and steaming coal is expected to rise significantly within the next 25 years. A large proportion of the State's anticipated increased production to between 117 and 177 million tonnes by the year 2000 is likely to come from this area.

Jan 1, 1979

By Mark A. Koestel

Cobalt-sulfide mineralization can he found in potentially economic quantities where permeable, basal Cambrian formations "pinchout" against Precambrian pal eotopographi c highs. These environments are common around the Saint Francois Mountains of southeastern Missouri and they share many similarities with the geologic environments of Zambia and Zaire in South Africa. Exploration for this type of deposit involves test drilling targets identified by trend analysis from past drilling, geophysics, geochemistry and a comprehensisve study of regional geology and isopach maps. Innovative ideas, new exploration concepts and insoluble residue geochemical methods may provide the necessary "edge" needed to complement basic geologic understanding leading to ore discovery.

Jan 1, 1987

By P. Somasundaran

Three major types of solution chemical equilibria involving flotagents (Le. flotation reagents such as collectors, frothers and modifiers), minerals and solution play a crucial role in determining the behavior of complex flotation systems. Minerals of phosphates (apatite and francolite), tungsten (wolframite and scheelite) and associated carbonates (calcite and dolomite) are sparingly soluble in aqueous solution and form dissolved mineral species in bulk solution. Such dissolved species interact with mineral solids, often resulting in surface conversion of the minerals. In addition, they can interact with various flotagents and lead to surface or bulk precipitation and loss of selectivity in the flotation. Relevant solution equilibria of such sparingly soluble minerals and their interactions with oleic acid and structurally modified reagents were determined in this study using a multi-pronged experimental approach. Methods to manipulate and control the solution chemical equilibria and thus achieve selectivity in flotation systems are discussed.

Jan 1, 1990

By C. V. Davis

In the lnvestlg::ìt1on of mAthods for aSS8.7ing platin",. conducted by the Bureau ot MinAs, reoent experiments have d~velopad tha~ with ce..tain orei, especially when thr, quantity Of platinum 1s eonlidarablfl, nit'!le acid w111 not etfßct a iepard-Han of platinum and pa11adium. 'lhe following m;lthod has been found to be accurate and to reiu1 t in a complete S''lun''ation of' th~3:l metals. It is therefo 1" '!eeommei:ed that 1 t ba followed rath::r- than the method of separation with nitrio acid, givèn in Technical Pape'! 270.* At line 22, pagi 14, of that paper, bAglnnlng with ~tarm th,~ metals '.'ith dilute¡ nitrio acid," strikE out the rest of the paragraph, and substttutt~ the pro_t cedure g1 ven below. ?lunder and Thuringer.. have developed mnt¡iods for th"i sflparation of palladium from all the platinum metals exoept platinum bj m ,ans of dlmethy- 19lyoxlme. They state that the~ is no action for several hours if an excess of dimeth¡lglyoxime is added to an aqueous solution of ohloroplatinic acid in the cold, alio that only on boiling is the platinum pTecipi ated ¡~d than only PST't of the platinum i srenoved from the sUut1on. They found that palladium 1s p~ecipi tated quati tat! vely in the oold as (CaH 4N40 Pd) which is insoluble tn water, dilute hydroohlorio acid, dilute acetIc aofd or in 50~ ethyl alcbhol. All of their pT'90ipi tations we~p Carl". ied out ~hile the solutions were being heated. This caused a pal"tia~recipltation of the platinum along wi th the

May 1, 1922

By P. Kobylin, K. Haavanlammi, K. Valkama

"Base metals and precious metals can be recovered from a nickel matte or nickel concentrate using the Outotec nickel chloride leaching process. The raw material is leached with hydrochloric acid and the metals are recovered by solvent extraction, where ammonia is used to control the pH. Ammonium chloride is regenerated to ammonia and the side product of this step is calcium chloride solution. The regeneration utilizes either calcium oxide or calcium hydroxide. The calcium chloride solution is used to convert sulfuric acid into a hydrochloric acid solution while producing pure gypsum as a side product. The regeneration and reuse of ammonia and hydrochloric acid in this process will have a positive impact, from the point of view of both operating costs and environmental sustainability. This paper concentrates on the test work and technical concept development performed by Outotec to implement and develop chemical regeneration and recycling into a vital part of the nickel chloride leaching process.INTRODUCTION According to a nickel market analysis, the nickel market is expected to grow in the future. Main driver for this growth is the increase in stainless steel consumption as the living standards are equalizing globally. The expected increase in the amount of electrical cars and the need for nickel in the batteries of electrical cars also gives potential for the increased need for nickel in near future. At the moment the use of nickel in nickel-cobalt-manganese (NCM) and nickel-cobalt-aluminium (NCA) Li-ion batteries is in the range of 14 ktpa. It is estimated to increase to the level of 90 ktpa by 2025. In every era of the nickel industry, Outotec has been constantly developing new processes to create environmentally sustainable and economically viable processing routes. The Outotec® Nickel Matte Chloride Leaching process is a great example of a process that is flexible regarding raw material and could also treat nickel raw materials that are difficult for smelters. Outotec’s main options for pyrometallurgical nickel treatment include the Outotec® Direct Nickel Flash Smelting process (DON) and the Outotec® Ausmelt TSL process. The DON process is operated in Boliden Harjavalta Nickel Smelter in Finland. Ausmelt process is in use for example in Daye nonferrous plant in China. In the Outotec® Direct Nickel Flash Smelting Process, a sulphide nickel concentrate is processed in an Outotec Flash Smelting Furnace (FSF). Producing concentrates and processing them by Outotec Direct Nickel Flash Smelting to matte followed by hydrometallurgical refining offers a reliable route from concentrate to product. In the DON process, high-grade matte with low Fe content is produced in the FSF and the valuable metals in the slag are recovered in an electric furnace (EF). The Outotec® Ausmelt TSL process can use a large variety of raw materials (concentrates, secondary material and scrap metal) as feed. Fuel and oxygen are injected into the furnace through TSL (Top Submerged Lance) and this enables efficient smelting. Both Flash Smelting and TSL plants produce nickel mattes, which can be refined with Outotec hydrometallurgical processes."

Jan 1, 2017

By Robert Maes, Robert de Strycker

The Cu-Sn-As systeM was studied in the region near the Cu-42 and (214-As binary diagrams, where reactions in the solid state appear, resulting from the decomposition of the y(Cu-Sn) phase and from the formation of the 7 phase (Cu,As). The techniques used were microscopic observation, thermal analysis by dilatometry, and X-vay diffraction. The formation of the 7 phase gives rise to a ternavy pevitectoid veaction; the decomposition of the y phase gives rise to five transitional reactions. The temperatures of almost all these reactions could be determined; in the most favorable cases , the accuracy of this determination was of 11.5-C. The 7 phase is stabilized by tin additions, the arsenic atoms being replaced by tin atoms up to 35 pct; this has allowed the preparation of pure j) phase and the confirmation, by extrapolation, of the conrposition of this compound in the Cu-As diagram. In the first part of this work, the solidification reactions in the Cu-Sn-As phase diagram were studied. In the copper corner, the structure of the alloys presented the evidence of reactions in the solid state: on the one hand, all the alloys containing the y phase of the Cu-Sn diagram showed, under the microscope, that this phase had formed different decomposition products after complete solidification; on the other hand, the appearance of the 7 phase of the Cu-As diagram necessitated the introduction of a peritectoid formation reaction. The study of the decomposition of the y phase has been done by preparing about forty alloys that were homogeneous y at high temperature. The formation of the 7 phase has been studied by means of a few alloys with a composition near the homogeneity field of this phase at room temperature. The part of the Cu-Sn phase diagram of interest for this study is represented by Fig. 1, with the phase designation which will be used in the remainder of this paper; it is drawn after Hansen and Anderko.' The Cu-As diagram has already been presented in Part I of this work; the significant features of this study are the existence of the arsenides CusAs and Cu5Asz, and the formation of a compound CUEAS, designated as the 7 phase, by a peritectoid reaction at about 325°C. EXPERIMENTAL METHODS The fundamental technique for the investigation of this part of the Cu-Sn-As constitution diagram was microscopic observation; the greatest part of the observed alloys has also been subjected to thermal analysis by dilatometry; a few selected alloys have then undergone an X-ray analysis by powder diffraction. Alloy Preparation. The alloys were prepared from the same products as in Part I of this study: cathode copper, arsenic with a purity better than 99.5, and tin with a purity of 99.98. The fusion of the ternary alloys was realized from

Jan 1, 1967