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By R. C. Ku, R. G. Davies

The stress-strain behavior of Fe-C and Fe-Ni solid-solution alloys has been investigated at 25°C. It is found that the rate of solid-solution strengthening is dependent upon the strain at which the yield stress is measured, the macroyield stress being much more concentration-dependent than the microyield stress. In fact the addition of nickel does not lead to any increase in the microyield stress of iron. The primary effect of increasing the carbon or nickel content is to increase the slope of the stress-strain curve in the microyield region; this effect has been correlated, by means of transmission electron microscopy, with a decreased ability of the dislocations to cross-slip. It is concluded that the Mott-Nabarro theory is a good description of true solid-solution hardening in these and other iron-base alloys. A.LL theories of the solid-solution strengthening1-4 indicate that the flow stress of an alloy increases both with solute concentration and "misfit" between the solvent and solute atoms. The functional relationship between strength, solute concentration, C, and misfit depends upon the particular theory. Mott and Nabarro1,2 and Schoeck and Seeger3 both predict a linear increase in strength with concentration, while Fleischer4 indicates that the strength should be proportional to C1/2; there are in the literature experimental observations to support both these compositional dependencies.1'8 The experimental evidence used to support the theories is the change in macroscopic yield stress (strain, e, = 10-3) with composition. However, recent investigations have revealed that solid-solution strengthening in a Cu-Al single crystals7 and in Fe-V polycrystal-line" alloys depends upon the strain at which the flow stress is measured; a flow stress in the microplastic range (e = 10-6 to 10-5) is much less concentration-dependent than the macroyield stress. Since the theories of solid-solution strengthening are concerned in particular with the stress to move a dislocation in a dislocation-free matrix, they should only be compared with microyield-stress data; it will be shown that in a material deforming homogeneously the microyield stress (e = 10-6) is approximately the stress to move through the matrix those dislocations which have been nucleated by stress concentrations such as particles or grain boundary ledges.9-11 In contrast, the macro-yield stress is more complex in that it is affected by several phenomena: dislocation multiplication, dislocation interactions, and the ease of propagating slip across grain boundaries. For example, it is experimentally observed that when long-range order12'13 or solute effects10 restrict cross alip the grain boundary

Jan 1, 1967

By William H. Lyon

In 1950 the Program Staff of the Department of the Interior undertook an exploratory study in the projection of energy requirements of the nation. This work was reported in Bureau of Mines Information Circular 7582 by H. J. Barnett. In that preliminary study Mr. Barnett, after exploring the nature of the energy economy in some detail, evolved a method for estimating how much energy will be required in the future, based on estimates of trends in efficiency of energy utilization in specific applications, the physical output of specific energy-consuming industries, size of the population, productivity advances in the economy at large, consumer preferences, and other factors. Considerable new information was developed regarding the nature of energy demands and the possible levels of requirements for each fuel under various assumed business conditions. The study analyzed the interrelationships, including substitutions, among the fuels and emphasized the need for viewing the energy economy as an integrated albeit complex whole. This exploratory study showed a need for a single comprehensive statistical re-port that would assemble and show in a uniform manner the diverse published statistical data on energy commodities now scattered through many publications. A particularly important need was for a set of historical statistics showing the production and consumption of all energy on a B.t.u. basis. As the prospective size and nature of the future energy requirements of the nation are matters of continuing importance, this report was prepared to assist further investigations of the subject. In this report the authors undertake to assemble and present in tabular form, on a uniform basis, the production and use of each of the fuels and electric energy in the United states for three census years -1929, 1939, and 1947. The year 1947, rather than a later year, was selected because it is the most recent year for which census data are available showing the consumption of fuel by each of the manufacturing industries. It is hoped that making data for these 3 years available in one re-port will provide the needed statistical background for further studies of fuel requirements and supplies.

Jan 1, 1951

By Izabelle Lannes Salgueiro Ferreira

O presente trabalho tem como objetivo mostrar o Programa da Qualidade desenvolvido na Gerência de Laminação a Quente da Votorantim para aperfeiçoar o sistema de gestão da qualidade. Tendo como base a melhoria no método de análise dos parâmetros de processo e produto, foi identificada a oportunidade de desenvolver um modelo integrado com a finalidade de coletar resultados dos parâmetros produtivos de forma instantânea, obtendo o controle online do processo e produto. A implantação do ProQuali possibilitou a realização de análises de campanha para produtos críticos pela equipe técnica e auxiliou a equipe operacional na tomada de decisão online durante o processo. Com isto foi possível evidenciar uma evolução significativa nos principais indicadores do laminador: índice de rendimento metálico (RM), utilização (IU) e geração de produtos não conforme (NC).

Oct 30, 2017

By Cintia Braga

O processo de retificação é empregado na fabricação de componentes que requerem excelente qualidade dimensional com elevado acabamento superficial. O desempenho deste processo depende muito das condições de lubri-refrigeração produzidas pelos fluidos de corte, que são utilizados para amenizar os problemas que afetam a integridade superficial das peças, como queima e danos microestruturais, e também proporcionar melhor desempenho do processo e aumento da vida útil do rebolo. Entretanto, os fluidos de corte são uma das fontes mais problemáticas na manufatura, pois são produtos nocivos ao meio ambiente e a saúde humana, e aparecem como elemento determinante para a otimização do processo de fabricação. Desta maneira, este projeto visa analisar o comportamento do fluido de corte integral comercial em comparação com formulações biodegradáveis (óleos de soja e milho) no processo de retificação cilíndrica externa de mergulho no aço ABNT 4340 temperado e revenido com dureza média de 52 HRc. A avaliação do desempenho dos fluidos consistiu na análise da integridade superficial (rugosidade, microestrutura e microdureza) e no desgaste do rebolo. Os resultados comprovaram a eficiência dos óleos vegetais e viabilidade do uso no processo de retificação, proporcionando melhoria na eficiência do processo e contribuindo para uma manufatura ecologicamente correta.

Aug 7, 2018

By Altair Lúcio de Souza

A laminação de tiras a quente com laminadores Steckel tem como característica um perfil de temperatura mais baixa nas pontas sendo este um dos motivos que geram cargas de laminação muito mais altas nesta região. A carga de laminação elevada tem como consequência no processo a geração de desvios de planicidade e o alto risco de rompimento do material nos passes finais de laminação. Este trabalho tem como objetivo demonstrar os benefícios da utilização da estratégia de Tapering para a laminação de tiras de espessura fina em laminador Steckel. Foi feita a comparação das cargas de laminação do material laminado e o acompanhamento dos resultados de planicidade obtidos antes e depois da implantação desta função. Ao fim do trabalho verificamos que a estratégia de Tapering é essencial para o processamento de materiais finos com laminadores Steckel.

Jul 30, 2018

By Leonardo Lúcio de Araújo Gouveia

Este trabalho objetiva o estudo da influência da adição de fibras vegetais de bambu e cana-de-açúcar nas propriedades mecânicas do concreto. Para este trabalho foram confeccionados corpos-de-prova cilíndricos e prismáticos nos quais foram adicionados 2% e 5% em volume das fibras à massa do concreto. Após a cura, conforme NBR 5738 (2003) [1], os mesmos foram testados via ensaios de resistência à compressão conforme NBR 5739 (2007) [2], resistência à tração por compressão diametral, conforme NBR 7222 (2011) [3], resistência à tração na flexão conforme NBR 12142 (2010) [4] e módulo de elasticidade estático, conforme NBR 8522(2008) [5]. Verificou-se após os testes que todos os concretos produzidos atenderam a resistência mínima a compressão de 20 MPa, recomendado pela NBR 6118 (2003) [6] para fins estruturais. Foi observado um aumento da resistência à compressão em relação à mistura padrão. O concreto com adição de fibras de bambu apresentou melhor resistência mecânica em relação ao concreto com adição das fibras de cana-de-açúcar e ao concreto sem adição.

Aug 7, 2018

By Wellington Fernandes Junior

O uso de blocos de solo-cimento é considerado um método construtivo mais barato do que o convencional, visto que uma das matérias-primas, o solo, é abundante. Soma-se a isto, o fato de não haver uma destinação correta para o resíduo proveniente da fabricação de papel. Visando redução de custo de produção de tijolos de solo-cimento e uma alternativa sustentável para aproveitamento do resíduo, a proposta do presente trabalho é avaliar a incorporação do resíduo da fabricação de papel na mistura solo-cimento para confecção de tijolos modulares prensados com dimensões de 30cmx15cmx7cm. Foram testadas diferentes proporções de solo e resíduo e mantendo sempre a mesma massa de cimento. Foram realizados ensaios de absorção de água e resistência à compressão aos 28 dias de cura. Os resultados foram analisados a fim de verificar a viabilidade da incorporação do resíduo nos tijolos em maior quantidade possível, obedecendo as exigências impostas pelas normas regulamentadoras de blocos de solo-cimento. Foi concluído que a incorporação do resíduo, em quantidades adequadas, é viável na produção de tijolos de solo-cimento, reduzindo o custo da produção, além de diminuir os impactos ambientais com o destino correto do resíduo.

Oct 30, 2017

By Alexandre Gonçalves Andrade

Com a queda na qualidade dos minérios de ferro das minas da região de Minas Gerais, torna-se cada vez mais necessárias maiores energias de moagem para a retirada de impurezas, tais como SiO2 e PPC (perda por calcinação). Este fato implica em maiores superfícies específicas do minério de ferro para a etapa de filtragem, com consequente perda de produtividade e aumento da umidade final da torta formada. Assim sendo, existe grande impacto deste teor de umidade na etapa de aglomeração (taxa de crescimento de pelotas) e na perda de produtividade dos fornos de endurecimento. Como alternativa para a redução do teor de umidade da torta do pellet feed na etapa de filtragem, avaliou-se a utilização de auxiliares de filtração (surfactantes) nas etapas de filtragem e pelotamento, tanto em teste em escala piloto e industrial.

Aug 16, 2017

By A M. Lechner, S Arnold, M J. Gillespie, P D. Erskine, D R. Mulligan, A T. Fletcher, A Gordon

Mine ecological monitoring schemes are often conducted only to address compliance and in some cases do not have the sufficient statistical power or understanding of ecological systems to assess, quantitatively, the meeting of rehabilitation targets or mine impacts. Monitoring schemes for rehabilitation commonly rely on analogue sites or premining baselines (reference sites) to assess whether rehabilitation sites are ecologically similar and thus successfully rehabilitated. In the case of monitoring for mine impacts, if the impacted sites diverge from reference data, the site is considered to be impacted. Fundamental to any monitoring scheme is testing the sampling design to ensure that it can detect these differences if they are present through adequate sample sizes (ie statistical power). However, a good understanding of the ecological system is required to ensure that differences detected are ecologically significant. Modelling ecosystem properties can provide a quantitative understanding of how ecosystems change over time and space, in response to natural environmental variations and thus aid in determining significant ecological differences. Furthermore, modelling methods can be used to predict future ecosystem states. Within the ecological literature, guidelines for robust statistical monitoring designs and modelling methods exist but are not routinely being used in the mining industry. This paper uses simple examples to discuss: problems with current compliance monitoring methods; importance of robust statistical techniques; and how modelling can assist rehabilitation assessment and guide monitoring schemes. The aim of this paper is to describe general monitoring and modelling methods that could be potentially used for mine site monitoring and closure assessment. These methods are often considered by mining companies as an extra expense that provide little practical benefit, and the domain of academia; however, engaging these methods may be more cost-effective in the long-run than conducting untargeted monitoring schemes that give no confidence to regulators on whether rehabilitation criteria have been met. Furthermore, monitoring programs in mining contexts provide a good opportunity to better understand long-term ecological patterns and test the application of more rigorous modelling approaches as the life of many mines tends to be greater than ten years.CITATION:Lechner, A M, Arnold, S, Fletcher, A T, Gordon, A, Erskine, P D, Gillespie, M J and Mulligan, D R, 2012. Embracing modern ecological methods - Monitoring and modelling for mine closure, not compliance, in Proceedings Life-of-Mine 2012 , pp 25-32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By Luis Noval García

El presente texto describe la importancia de la explotación de yacimientos carboníferos. Para ello, revisa la potenciación del PROCARBÓN como institución mediadora entre productores y consumidores donde se establecen reglas adecuadas a la realidad económica del Perú.

Jan 1, 1986

By S Watson, L Martinez

Mine projects are complex opportunities that demand a constant assessment of uncertainty, ie risk and upside potential. This is because the value of a mine project is typically influenced by many underlying economic and physical uncertainties, such as metal/mineral prices, metal/mineral grades, costs, schedules, quantities, and environmental issues, amongst others, which are not known with much certainty at the beginning of the project. But, is uncertainty an enemy or an ally of the mine planner/analyst? To answer this question, this paper first assesses and elaborates upon the general concept of uncertainty. It then looks at the different sources of uncertainty in a mining project, such as the orebody, costs and product price uncertainties, and their effect on the final project value. Next, a general?review?of current mine evaluation techniques highlighting their limitations when dealing with uncertainty is made. Finally, an extended evaluation and risk management framework that addresses the existing uncertainty in the (greenfield/brownfield) mine evaluation process is proposed. One important characteristic of this framework is that it uses and manages uncertainty in order to generate additional value to the project; this is done through operational and managerial flexibility, which allow mine planners to minimise/maximise project risk/upside-potential giving a more realistic estimate of the projectÆs market value - this is shown in practical and simple examples occurring at different stages of a mine project, such as exploration and operation. Final conclusions are provided at the end.CITATION:Martinez, L and Watson, S, 2012. Uncertainty - An important source of (additional) value for mine projects, in Proceedings Project Evaluation 2012 , pp 131-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By H. J. Chalmers

THE H.B. MINE and concentrator are located in the Nelson Mining Division of British Columbia, on the north side of the Sheep Creek valley about seven miles southeast of the town of Salmo. It is an operation of The Consolidated Mining and Smelting Company of Canada, Limited (Cominco), which has its metallurgical plants at Trail, about 25 miles west. The property was originally staked about 1907 by Horton and Benson, whose names are commemorated in the designation "H. B." Up until 1927, a considerable amount of development work was done in the upper levels by various companies. Cominco purchased the ?property in 1927 and carried out intermittent work until 1946. Following this, an extensive surface diamond drilling programme and a subsequent underground exploration were undertaken. Sufficient ore was outlined 'to warrant the construction of a 1,000: ton concentrator. This was started in April, 1952, and completed by the spring of 1953. However, because of adverse base metal market conditions, operation was deferred until May, 1955.

Jan 1, 1957

By W L. Daniels, C Stilson, C Zimmerman

Mineral sands mining for ilmenite, rutile and zircon has disturbed over 1000 ha of prime farmland in Virginia (USA) since 1997 and additional areas are likely to be disturbed in Virginia and North Carolina (USA) over the next 15 years. Full-scale mining operations at the Old Hickory Project in Virginia were initiated in 1997 by Iluka Resources Inc. and restoration protocols have continued to evolve in response to a variety of economic, technical and social issues. Early on, the return of these lands to agricultural row-crop production was complicated by vertical stratification of tails + slimes and lateral variability in soil physical conditions in the reclaimed pits and by limited topsoil return. Virginia Tech and Iluka have worked cooperatively with all stakeholders for over 20 years to review the pre-existing research base, conduct new and innovative site-specific research and thereby provide reasonable expectations of post-mining soil productivity levels. In 2004, Virginia Tech, Iluka Resources and a local leaseholder (Carraway-Winn family) agreed to jointly manage a 45 ha research demonstration farm where the long-term effects of alternative soil reconstruction practices are being rigorously monitored for both row crops (corn and wheat) and forage production. All mined land crop yields are also compared to an adjacent undisturbed exceptional quality prime farmland soil. Row crop yields between 2005 and 2010 were significantly above county average yields (regulatory target level) and approximately 75 - 80 per cent of undisturbed adjacent prime farmlands. The state regulatory authority has recently relaxed its position on the necessity of topsoil return versus use of topsoil substitutes based on appropriate on-site research results and the ability of the reclaimed soils to meet comparative local county crop yield targets. This cooperative effort allows all clientele groups to objectively assess the post-mining productivity of these mined lands while providing an invaluable educational opportunity for the mining industry. CITATION:Daniels, W L, Stilson, C and Zimmerman, C, 2012. Development of effective rehabilitation protocols for mineral sands mining in Virginia, USA, in Proceedings Life-of-Mine 2012 , pp 97-104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By G. Deschênes

Silver minerals are known to have slow leaching rates and low overall extraction and require a high concentration of cyanide and a long retention time to maximize leach extraction. Their response to cyanidation is considered mild to moderately refractory, largely due to complex mineralogical compositions. New research on improving the dissolution of silver minerals in cyanide was performed using high-purity minerals, as well as a high-grade ore sample from the Kupol property, owned 75% by Kinross Gold. The high-purity silver minerals studied in the leach investigations included acanthite, stephanite and pyrargyrite, which were also the predominant silver minerals in the Kupol ore sample. Dissolution of silver from acanthite produced only 37% extraction in 48 hours of leaching with 500 ppm NaCN. Analysis of the leached acanthite surface showed appreciable formation of polysulfide species, which can interfere with silver leaching. Adding lead nitrate into a pretreatment stage increased the acanthite silver extraction to 86.2%. No polysulfide species were formed with the addition of lead nitrate from the surface analysis. Cyanidation of stephanite and pyrargyrite produced very low dissolutions of silver, only 12.6% and 10.4%, respectively, in the absence of lead nitrate. Silver extraction from stephanite improved to 98% by adding lead nitrate directly to the leaching stage, whereas pyrargyrite required a pretreatment with lead nitrate to extract 83.2% Ag. With the addition of lead nitrate, the mineral surfaces had a PbO species and minor amounts of Pb(OH)2 and antimony was oxidized on the stephanite and pyrargyrite surfaces during leaching. There was a much greater concentration of Sb(V) on stephanite relative to pyrargyrite. Therefore, lead forms a redox couple on silver mineral grains and favors the oxidation of silver minerals. The high-grade Kupol sample assayed 22.6 g/t Au and 359.3 g/t Ag following treatment by gravity separation. Gold and silver extractions from the Kupol sample were 94.5% and 82.9%, respectively, using 500 ppm NaCN and 250 g/t lead nitrate. The findings to improve the extraction of silver from the ore sample with lead nitrate addition were congruent with those to improve the extraction of silver from the individual high purity minerals. Pretreatment did not, however, improve gold or silver extraction significantly with the ore sample.

Jan 1, 2011

By Paul B. Valenti

The Nevada Moly Operation of Anaconda Minerals Co., (a molybdenum/copper ore body) was initiated in 1978, with a contract to Bechtel Civil and Minerals Inc. for construction of a mining and milling facility near Tonopah, NV. Ground was broken on the concentrator portion of the project in August 1979$ with a multi-phased startup of the mill beginning in June 1981. Processing design tonnage of 20 000 t/d (22,000 STPD) was reached in early 1982. Major pitfalls of rapid design and implementation of engineering, construction, and startup are considered. The operation of the concentrator including SAG milling, ball milling, bulk rougher flotation, copper/moly separation, moly regrinding and cleaning, thickening, and product loadout are discussed.

Jan 1, 1983

By E. A. Sondreal

The Bureau of Mines investigated the use of lignite char for producing carbon disulfide; CS2 production rates were as high as when wood charcoal was used as raw material. The maximum space velocity for CS2 produced in the bench-scale study was 9,280 hour-1, reacting sulfur and lignite char at 792° C. The reaction temperature and the temperature at which the char was carbonized were the two most important factors in determining CS2 production rates. Increasing the carbonization temperature in nitrogen from 400° to 900° C advanced the temperature at which carbon disulfide was first produced from 550° to 850° C. The average activation energy for reacting chars with sulfur was 44,000 cal/g mole. The reaction was first order with respect to the partial pressure of sulfur. Increasing the rate of sulfur admission caused a decrease in rate of production at otherwise similar conditions. Rates were not affected by either char size or sodium carbonate catalysis. High space velocities at moderate temperatures using inexpensive lignite chars could offer an economic advantage in the manufacture of carbon disulfide provided that yields were attractive.

Jan 1, 1967

By E. F. Foerster

The Bureau of Mines used a diphenyl ether calorimeter to determine the heat contents of natural and synthetic blast-furnace slags. For solid slags, enthalpy (HT-H298) at 1,448° to 1,680° K ranged from 282.1 to 348.5 cal/g (±3 percent); liquid slag values were 400.1 to 514 cal/g (±3 percent) in the temperature range between 1,626° and 1,890° K. Experimental results for liquid slags were 14.3 to 16.2 percent higher than the enthalpies calculated from thermodynamic tables; values for solid slags ranged from 5.3 percent lower to 3.9 percent higher than calculated values. Experimental results for liquid synthetic slags ranged from 14.9 to 24.3 percent higher than the calculated enthalpies; values for solid synthetic slags were from 1.0 to 3.4 percent higher.

Jan 1, 1967

By Thomas M. Nasiatka

Tests with a high-pressure water jet were conducted in the steeply pitching Roslyn No. 5 bituminous coalbed in the Roslyn No. 9 mine, Roslyn, Wash., to determine the feasibility of extracting coal from pillars and from a solid coal face in development without drilling and blasting. During pillar mining, using a hand-held monitor, the best results were obtained with a 0.150-inch- diameter nozzle, a water pressure of 3,500 psi, and a flow rate of 38.5 gpm.3 The rate of mining and productivity were 0.74 ton per minute and 16.6 tons per man-shift, respectively. During development mining, using a monitor mounted on a roof jack, the best results were obtained with a 0.148-inch-diameter nozzle, a water pressure of 4,500 psi, and a flow rate of 40.0 gpm. In one section of the mine where the coal was relatively hard, the rate .of mining and productivity were 0.10 ton per minute and 5.7 tons per man-shift, respectively in another section of the mine where the coal was relatively soft, the rate of mining and productivity were 0.51 ton per minute and 8.3 tons per man-shift, respectively. The tests showed that hydraulic mining methods were more productive than conventional mining methods in pillar mining. In development the productivity of hydraulic mining depended primarily upon the coal hardness. Compared with conventional methods, hydraulic mining methods were less productive where the coal was relatively hard and equally as productive where the coal was relatively soft.

Jan 1, 1963

By C. R. McClung

"Molybdenum, in the form of molybdenite, is a common byproduct of many copper mining and concentrating operations. Contrary to most copper sulfide minerals where recovery is principally liberation controlled, the recovery of molybdenite is much more complex with fully liberated particles commonly lost to tailings. It is this complexity that facilitated the necessity for a geometallurgical investigation of molybdenite from the Bingham Canyon deposit. The aim of this investigation was to determine the effect mineralogy and/or mineralogical attributes (i.e. morphology, angularity, liberation, size) have on the recovery of molybdenite in the processing circuit. A set of samples was collected from the ores and products produced by Rio Tinto Kennecott’s Copperton Concentrator. All samples were analyzed using normal polarized reflective light, Mineral Liberation Analyzer (MLA) and X-ray diffractometery (XRD) techniques. The results of this investigation revealed the presence of two distinctly different types of molybdenite, which have been identified as the two polytypes of molybdenite, i.e. hexagonal (2H) and rhombohedral (3R). The 2H polytype occurs as textbook-shaped particles in quartz-molybdenite veins that are located in the core of the Bingham Canyon deposit. The 3R polytype occurs as disseminated, “ball”-shaped particles with a dull or frosted appearance along the margins of the mineralized intrusive body or central core. Concerning their metallurgical behavior each type exhibits unique metallurgical properties that are consistent with those reported in the published literature. For instance, the 2H polytype is easily ground and kinetically “faster” floating with surface attributes that are amenable to higher rates of recovery. This commonly results in the production of a high quality molybdenum concentrate under normal operating conditions common to most copper concentration operations. In contrast, the 3R polytype is difficult to grind and kinetically “slower” floating with surface attributes that less amenable to recovery under normal operating conditions. Therefore, in deposits with higher concentrations of the 3R polytype, modifications to the normal operating parameters may be necessary to improve the recovery of molybdenum. Finally, a preliminary investigation into the metal budget of porphyry Cu and Mo deposits indicates that a positive correlation may exist between the total economic metal budget and the polytype content. For example, higher concentrations of the 3R polytype appear to be more prevalent in Au-enriched porphyries versus Mo-enriched porphyries. This observation may also serve to help explain why it is easier to obtain high rates of recovery in Mo ± W-rich deposits, which contain little to none of the 3R-polytype. Consequently, the potential for the metal budget of a porphyry deposit to be used as an indication of the molybdenite polytype present, as well as its impact on the economics (exploration) and/or on the processing circuit (plant design) could exist. In conclusion, this investigation highlights the necessity of understanding the mineralogical properties or characteristics of molybdenite and/or other economic mineral(s), as these can and will have a direct impact upon the performance and plant optimization."

Jan 1, 2016

By K. Darcovich

The wettabilities of agglomerates made from coals of several different ranks were measured by the adhesion technique. Oil levels from 0 to 10% by weight were used. As was expected, it was found that higher-rank coals are more easily oil-wetted and that the surface properties of the agglomerates correlate with agglomeration recovery and ash removal data.

Jan 1, 1992