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By G. Lindkvist

Roasting of concentrates with high impurity levels is normally done in multiple- hearth furnaces where the concentrates are heated with oilfired burners in order to remove As, Sb and Bi before the final sulfide oxidation. Although it is a countercurrent heat exchange process it uses a lot of oil. In order to develop an energy saving, and from a working environmental point of view a less harmful process than the multiplehearth process, pilot-plant tests have been done in a two-stage fluidized bed for partial roasting. The test materials have been As-rich concentrates with 8-25 % As some 5b and Bi. The Cu-content was 0-28 %. The tests have been successful with <0.3 % As,in the calcine and with an elimination of 5b between 80 and 90 %. In order to achieve the proper conditions for good impurity removal, 1.e. right temperature,residence time and sulphur potential, the tests were performed in a special designed roaster. The roaster consists of two beds with the facilities for recirculation of calcine, preheating of the blast, and possibility to use oxygen enrichment. The construction makes it easy to control the reactions that generate the heat in the bed and reduce the amount of dust that passes through the cyclones. As two roasting steps are used, the possibility to obtain optimal conditions for impurity removal is improved and the calcine can either be smelted to a normal matte, or after being dead-roasted in the second stage, be leached in the normal way for gold extraction. The calcine was smelted with slag. The matte and the slag obtained had low quantities of impurities in the matte and a favourable distribution of impurities to the slag.

Jan 1, 1983

By Weibai Hu

Four methods to assess the relative flotability of fine coal have been tested: flotation with frother only, flotation with frother and collector, salt flotation, and timed-release analysis. A practical and simple criterion which combines the separation efficiency (capacity factor and kinetic rate constant (intensity factor) has been suggested. Five coal samples are chosen and tested. Based on test results, it is concluded that the flotability test with collector and frother is closer to practice, and, according to the suggested flotability criterion, coal fines can be classified into four categories of relative flotability: very easy, easy, moderate, and difficult.

Jan 1, 1987

It is a very great privilege for me to be able to address you tonight and I am deeply sensible of the honour which has been done me. I am equally sensible of the inadequacy of my training for the position of President of your Institute.May I say at once what a very great pleasure it is to have so many members from the mainland States visiting us here in Tasmania. We do hope that you will find pleasure and profit in your stay.Since the Annual Conference is always held in the vicinity of one or other of the great mining fields, it has become the practice for the Presidential address to review the history of the particular field and t(j) indicate its place in the economic structure of the country.I propose to follow this practice and to try and present to you a short picture of thÇ mineral industry as it has existed in Tasmania. None of the information is new it is available in diverse and remote geological reports and in publications such as Witham&apos;s Western Tasmania and the more recent Peaks of Lyell. The last composite approach was written twenty years ago by P. B. Nye and published as a Geological Survey Bulletin.I have enjoyed preparing this address because on occasion I find it refreshing to look back and see what was known and what was accomplished in the days when the going was a little tougher than it is now, and to speculate upon the reasons that drove men to do what they did. I shall therefore discuss the search for minerals in this State; the discoveries over the years; the elation with which the new fields are greeted; the disappointments attending some of them; the mines that have come and gone; and the...

Jan 1, 1958

By Cleo G. Rall

The method for determining the effective porosity of oil- and gas-bearing sands described in this report is a development of earlier methods (28)3/ devised by the Bureau of Mines. The apparatus bas been improved and made more convenient to use, but the procedure is essentially the same as that which has been in use for maw years. A tabulation at the end of the report gives the results of more than 4,800 porosity determinations for oil sands4/ in the fields of 13 States, A selected bibliography of references to articles containing descriptions and evaluations of various methods of&apos; determining porosity is included in this report. The method was devised and developed at the Petroleum Experiment Station at Bartlesville, Okla., as part of the Bureau&apos;s research on fluid-energy relationships and on methods of improving the recovery of crude oil from underground reservoirs.

Jan 1, 1954

By E Coffison, M Gibbs, C Bennett

The sustainable management of surface water associated with coal mining and coal seam gas projects is a considerable factor affecting the global competitiveness of these resource companies operating in Australia. Management of surface water can be costly, but effective water management and hence environmental stewardship enhances corporate social responsibility and the social license to operate. The surface water issues for the two industries are comparable, yet there is currently a lack of alignment between how Queensland, where the majority of AustraliaÆs coal seam gas projects are located, manages and regulates water on coal mine projects and coal seam gas projects.This paper provides a high level comparison of Queensland legislation and highlights the lack of alignment of this legislation regarding surface water management in these two industries. Through a case study, it looks at the surface water management process at a coal mine site based on the current legislation and principals of surface water management. QueenslandÆs lack of alignment in legislation regarding surface water management in these industries is understandable given the different development paths and time scales of the two industries. The coal mining industry has developed over a long period of time and the legislation has progressed in parallel, whereas, the coal seam gas industry is relatively new in Australia and the legislation has had to advance quickly. The lack of alignment between management of surface water for the two industries creates confusion among stakeholders and this adds complexity and additional transaction costs during the exploration, permitting and operational phases of projects, including landowners who may be affected.CITATION:Bennett, C, Coffison, E and Gibbs, M, 2013. Lack of alignment between regulation of surface water management in coal mining and coal seam gas, in Proceedings Water in Mining 2013 , pp 157-162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

By G Phillips

The Merlin project is situated 130 km south of Cloncurry in North West Queensland, Australia. It is located within the Pre-Cambrian Mt Isa Inlier and is grouped within the Eastern Fold Belt. The host rocks are metasedimentary rocks of the Proterozoic Kuridala and Staveley Formations adjacent to the Mount Dore Granite.Merlin zone represents part of the Mount Dore polymetallic deposit containing copper, zinc, silver, gold, lead, cobalt and most recently has been found to host molybdenum mineralisation. This is intimately associated with economic grades of rhenium, a naturally occurring metal that is an important component of high temperature aircraft engines. The host rock sequence is a 200 m thick zone of metasediments sandwiched between competent granite in the hanging wall and brittle quartzite in the foot wall. A distinct shear marks the contact between the granite and metasediments. The host rocks are comprised of three main rock types: black shale, phyllite and altered banded calc-silicate.Mineralisation dips to the east at approximately 45&#176; in a package of fine grained pelites and banded calc-silicates. The top 150 m of the sequence is typified by black shale and phyllite. The lower 50 m is typified by pink banded calc-silicate. The main molybdenite zone is located at and parallel to the pelite-calc-silicate contact. Down dip, the zone splits into two or three veins hosted by the calc-silicate rock suite and haloed by thin, steep dipping, stylolitic molybdenite veinlets.The deposit was discovered in 2008 by routine infill reverse circulation sampling conducted for the Mount Dore copper deposit. One hole penetrated below the main target Cu horizon and intersected visible molybdenite. During 2009 and 2010 a 50 &#215; 50 m diamond drill pattern delineated a total mineral resource of 6.7 Mt @ 1.3 per cent Mo, 23g/t Re, 0.3 per cent Cu (mostly Indicated Mineral Resource with minor Inferred Mineral Resource). The resource has been estimated using ordinary kriging within grade domains. Access to the deposit has commenced via a decline and production through the nearby Osborne flotation concentrator (70 km south) is expected in 2012. All facilities and resources are fully owned and operated by Ivanhoe Australia Limited, a public listed company on the Australian and Toronto stock exchanges.

Aug 22, 2011

By J. R. Tonry

In the grinding of dry non-metallic materials such as rocks, ores, gypsum, lime, and cement clinker, it is recognized that only a relatively small portion of the energy is utilized for actual size reduction, and the major portion of the energy used is converted into heat. As a result, heat is generated inside grinding mills imparting to the ground product a higher temperature than that of the mill feed. In some cases, as for instance in grinding cement clinker and gypsum into finished cement, it may be desirable to keep this temperature increase within certain limits, to avoid any change in the properties of the product and, because consumers may specify a maximum temperature of the finished product for reasons associated, with the tulimate use of the cement. The actual proportions of heat and useful work are somewhat indefinite. Some tests have indicated that nearly all the energy is converted into heat, and. other investigators have found that they could account for "everything except the noise." Investigations sponsored by the American Institute of Mining and Metallurgical Engineers, and carried out with an adiabatic calorimeter, indicated that a surprisingly high 19 percent of the energy might actually be used for size reduc¬tion. However, for the purpose of the following discussion it will be assumed that: (Fig. 1) 10% is lost in motor and gears 10% is lost by radiation and convection from the mill body 10% is used for size reduction, and. that 70% of the energy input leaves the mill as heat in the ground. product. A typical example (Fig. 2) would be a 7x22-ft tube mill operating in open circuit, driven by a 400 hp motor, charged with 77,000 lb of grinding media and producing 70 bbl or 26,300 lb of cement per hour. Reducing this cement from a clinker size of 96 percent passing a No. 16 mesh sieve to a specific surface of 3,230 sq cm per gm (Blaine) will increase the temperature of the cement approximately 143F above the temperature of the feed, as explained later. If the tempera¬ture of the clinker therefore is 125F, the finished cement will be 268F, which in some cases may be too hot. : When cement temperatures approach a range during grinding where dehydration of the gypsum becomes a problem, a logical consideration would be some means of reducing the temperature before it attains the range conducive to gypsum dehydration. Regardless of the varying degrees of heat generated within the mill or mills during grindingto various finenesses, consideration of the maximum safe limit for any type of cement being ground, which may vary fromplant to plant, govern in refining the mill circuit to obtain a safe temperature range. All plants are not necessarily required to do the same cooling job, and may or may not use cement coolers following the grinding circuit. (Not discussed in this paper). In the past, various means have been employed for controlling this temperature increase, Such means have included water cooling of the outside of the mill shell; equipping the shell with cooling fins; injection of moisture inside the mill; ventilation through the mill; and., in cases of closed-circuit grinding, drawing cooling air through the classifier; the purpose in all such cases being to remove heat from the grinding system.

Jan 1, 1958

By Wayne D. Gould

The Cities Service Company&apos;s Pinto Valley mine and concentrator lie about 6 miles west of the town of Miami, Arizona at an elevation of approximately 4,000 feet above sea level. The concentrator started its first ballmill in July 74 and all six were available by November. Every effort was made to reduce capital costs, consequently, each unit process was studied critically to eliminate excess capital costs without loss of efficiency. Equipment selection was made on the basis of proven dependability and operating costs rather than on low bids. The result is a very workable plant with some important innovations. The concentrator is nominally 40,000 tons per day. The flowsheet is typical with 3 stage crushing, single stage closed circuit grinding, flotation, regrinding of rougher concentrate and cleaning of the rougher concentrate. The major equipment list is: 1 60 x 89 Traylor Primary Crusher 1 84" x 20&apos; Stevens-Adamson Apron Feeder 3 7&apos; x 16&apos; Double Deck Tyler Screen 3 7&apos; Nordberg Standard Crushers 6 8&apos; x 20&apos; Tyler Screens

Jan 1, 1975

By João Batista Conti de Souza

A utilização de fundentes como fontes de CaO e MgO na carga de altos fornos é uma prática operacional bem conhecida e estabelecida pelos produtores de ferro primário na siderurgia mundial. As práticas podem ser encontradas nas literaturas através de trabalhos publicados onde são descritos e apresentados os respectivos benefícios obtidos. A muito que os produtores de ferro primário, pela rota alto-forno, tem se esforçado nos estudos e desenvolvimentos de cargas elaboradas alternativas através de acordos de cooperação técnica junto aos centros de pesquisas e universidades. Tais acordos visam a melhoria da performance dos aglomerados e dos reatores de redução. A dificuldade em produzir pelotas auto - fundentes, com garantia da manutenção das propriedades necessárias e que favoreçam o processo de produção de ferro primário via alto-forno, tem sido o desafio no que se refere á avaliação das diversas formas de amenizar os efeitos detrimentais da adição de fundentes, contendo altos teores do composto MgO, nas etapas do processo produtivo de pelotização, garantindo assim uma composição química, as características físicas e metalúrgicas do produto final (pelota queimada). O plano de pesquisa visou o desenvolvimento de um “novo produto”, pelotas de minérios de ferro auto - fundentes com alto teor de MgO com características superiores para suportar às solicitações impostas no próprio processo de sua produção, no manuseio e no atendimento às solicitações durante as etapas de redução e amolecimento e fusão nos altos fornos, quando comparadas ao uso em substituição as adições de fundentes ricos do referido composto.

Aug 1, 2018

By Raymond W. Hiteshue, Sam Friedman, Martin D. Schlesinger

The Bureau of Mines in cooperation with the El Paso Natural Gas Co. investigated the effect of high temperature and pressure at short residence times on the hydrogenation of a New Mexico coal to gaseous and liquid hydrocarbons . The study was made in a bench - scale semicontinuous unit at pressures of 500 to 6,000 psig , 480 ° to 1,000 ° C , and residence times of less than 1 minute to 15 minutes . Ammonium heptamolybdate was impregnated on the coal to furnish 1 percent molybdenum based on maf coal . Coal could be rapidly hydrogenated at elevated temperatures and pressures to yield large quantities of gaseous hydrocarbons and small quantities of lowboiling oils , high in single - ring aromatics . At 800 ° C and 6,000 psig and a residence time of 1 minute , the yield of hydrocarbon gas was 43 percent and of liquid hydrocarbons 9 percent , based on maf coal . With a 15 - minute residence time , the yield of gaseous hydrocarbons increased to 68 percent with a decrease in yield of oil to 6 percent . At higher hydrogen velocities , the yields of oil were much greater but contained large quantities of asphaltene . Low concentrations of molybdenum (0.01 and 0.1 percent ) or a high concentration of iron ( 1 percent ) were ineffective at 800 ° C , 6,000 psig , and short residence time .

Jan 1, 1964

By Simón D. Strauss

El presente texto señala los factores que han influenciado el comportamiento de los precios de los metales no ferrosos desde el fin de la Segunda Guerra Mundial. Tras la finalización de este periodo bélico, se dio una inflación que afectó los niveles de precios de todos los productos, alterándose los costos de cuatro de los ocho metales no-ferrosos en la industria minera peruana. Para ello, se realiza un estudio comparativo de los precios estipulados durante la Segunda Guerra Mundial con los precios vigentes al 31 de octubre de 1969. Asimismo se analiza los problemas básicos de oferta y de demanda, encontrándose que la demanda es mayor a la oferta, pese al descubrimiento de nuevas reservas del mineral. En consecuencia, tanto el avance científico y tecnológico como el desarrollo de la competencia son factores de importancia en la tasa de mercado actual que necesitan evaluarse constantemente.

Nov 20, 1969

By A. Nieto

This article is a review of previous discussions about underground mining method selection and classification with the purpose to clearly define and classify the two groups of variables (indicators) involved in the mining selection process: key deposit indicators (KDIs) and key mining method indicators (KMIs). This paper provides a simple and clear approach for the classification and selection of a feasible underground mining method based on a predetermined set of favorable deposit characteristics, which are defined as key deposit indictors (KDIs). This article also gives a summary of the key advantages and disadvantages associated with every underground mining method based on their key mining indicators (KMIs). The selection method given in this paper is based on defining field KDIs and comparing them to the KDIs that are favorable to every considered mining method. By cross validating a matrix of favorable KDIs, the paper presents a simple approach to rank several underground mining methods using a scale from favorable to less favorable accordingly to the ore deposit characteristics (KDIs). KMIs are used to further complement KDI rankings by analyzing every method’s KMI performance based on the expected productivity of the mining operation being considered. To further assist the reader through the selection process, this paper gives basic sketches representing each of the primary underground mining methods discussed in this paper. Each method is given using the same 3D isometric view as spatial reference to assist the reader with visual interpretation and comparison between methods.

Jan 1, 2010

By Valtemir Coelho Rodrigues

Nos últimos anos face a quantidade significativa de reparos gerais, parciais e emergenciais no revestimento refratário dos fornos em um curto período de tempo (média 02 fornos por ano), haviam paradas prolongadas dos fornos de cal para execução destes reparos onde era necessário prever todos os anos um alto valor para compra de cal, revestimento refratário e mão de obra de manutenção refratária. Afim de reduzir estes custos, aumentar a disponibilidade e produtividade dos fornos, foi feito um estudo e análise para detectar os problemas para serem tratados. Chegamos a conclusão que para aumentar a campanha dos fornos era necessário manter um ritmo estável de produção para evitarmos os choques térmicos no revestimento, treinamento da contratada e implantação do novo projeto para realização de limpeza dos canais o que eliminava o impacto de alavancas contra o revestimento, revisar o projeto o que mudaria a geometria e a composição de algumas peças refratárias, aperfeiçoamento dos monitoramentos do revestimento dos fornos para identificação mais rápido das ocorrências de problema de forma a permitir a aplicação de técnicas corretivas de maneira eficiente além de um intenso trabalho junto ao quadro operacional incluindo cursos e melhorias nos procedimentos que impactavam diretamente na operação correta dos fornos, além disso, melhorias significativas de manutenção contribuíram para melhor performance dos fornos de cal. É possível checar os resultados que este projeto proporcionou aumentando em 06 anos no mínimo a campanha dos fornos eliminando os reparos parciais e emergenciais realizando somente reparos gerais além da redução de custos.

Aug 17, 2017

By K. E. Harrison

The acid rain legislation has passed into law. This new law has caused the power generation community to investigate alternative methods to obtain compliance with the new legislation. One thing all of the power companies have concluded is the answer is not easy. Do we switch fuels to burn all low sulfur compliance coal? Maybe possibly only partial desulfurization by means of a dry sorbent system? Or, finally, maybe a wet scrubber system? Whatever the choice, the power community needs to investigate all of the alternatives. In 1988, ICF Kaiser Engineers, Inc. (ICF KE) responded to a request by the U.S. Department of Energy for the engineering development of advanced physical fine coal cleaning. ICF KE responded and was awarded a contract to conduct a multi-task program to develop an advanced flotation system to eliminate pyritic sulfur and retain as much energy as possible. ICF KE assembled a team that included members of industry, academia, and industry research organizations to conduct this multi-task program. The program includes sixteen (16) tasks. This team had personnel to help solve some of the anticipated problems and to provide industry prospective on the viability and commercial potential for any concepts proposed. The primary team consists of a major coal producer, Babcock and Wilcox, Eimco Process Equipment Company, and Virginia Polytechnic Institute and State University.

Jan 1, 1992

By Auã Kiahla, Tomi Kouvonen, Vinicius Miranda

Through numerical mathematical processing (Taylor’s approach and numerical derivation) the original data supplied by the accelerometer’s sensors was transformed into velocity and, after the data mining, a statistics residue analysis was applied in order to evaluate if the data from the prototype and from the traditional seismographs were similar. The data from each system was used to estimate the attenuation law and the results are shown in this paper

Feb 1, 2020

By Samuel Canchanya M

El presente trabajo señala la eficiencia de los métodos geoestadísticos en la industria minera a través de diversos ejemplos aplicados en yacimientos peruanos. En este sentido, los métodos estadísticos desplazan a los métodos tradicionales puesto que ofrecen mayor precisión, objetividad y eliminan la relativa accesiblidad de los depósitos minerales. Asimismo, el texto describe las diversas explicaciones de su aplicación en el campo de la ingeniería industrial, topografía, geofísica y batimetría en la industria del petróleo, al tiempo que refiere las causas de su escaso empleo como método teórica en la explotación de la industria minera.

Nov 8, 1984

By W. T. Isbell

Although the pressure to meet the heavy demand for lead still took precedence over new metallurgical developments in the field of roasting, smelting, and refining of lead in 1948 there nevertheless has been considerable activity in the experimental development of new processes and improvements as well as plans for the modernization of many plants both here and abroad. Increasing labor and material costs have stimulated the trend to greater mechanization, revamping of flow sheets, and construction of larger units wherever possible. Although there have been many serious labor stoppages in the United States, Mexico, and Europe, labor supply has improved in most plants even if it has fallen off in efficiency.

Jan 1, 1949

By G. Mawire

The extraction of scandium from its oxide with a task specific ionic liquid [Hbet][Tf2N] offers potential advantages of lower energy consumption, recycling of the extractant and reduced environmental impact compared to conventional methods. In this paper, the influence of reaction temperature, solid to liquid ratio and water to the ionic liquid ratio on the extraction of scandium from a synthetic scandium oxide (Sc2O3) system was studied. The influence of investigated parameters on leaching was very significant as approximately 98% scandium was extracted from its oxide after 72 h. Furthermore, the ionic liquid also selectively extracted 47% scandium after 48 h from a mixture of pure metal oxides containing oxides of tantalum, niobium, and scandium. The research demonstrated the potential of [Hbet][Tf2N] to selectively extract scandium from columbite processing tailings and other scandium bearing ores like Ixiolite, Heftetjernite and Tantalite which predominately contain tantalum and niobium.

By James C. Barker

Yttrium and rare-earth element. pegmatite dikes are associated with a peralkaline granitic and nephelene syenite complex near Dora Bay on southern Prince of Wales Island. Mineralized dikes were mapped and sampled during USBM investigations in 1987 and 1988. Coarse-grained pegmatite dikes, which emanated as late-stage magmatic fluids from the intrusion, further evolved into vein-dikes and ultimately silica-rich veins. The dikes can be traced up to two miles along a north-south zone. Lithophile elements exhibit a pronounced zonation in vein-dikes and veins that are distal to the Dora Bay complex with increasing values correlating with increasing distance from the complex. The pattern of mineralization suggests very late stage magmatic fluids containing the incompatable lithophile elements were injected into a preexisting north-south fracture zone. REE mineralogy exhibit fine-grained intergrowths of principally thalenite and bastnaesite with lessor monazite and eudialyte. Euxenite contains most of the columbium values and zircon is commonly associated with the dikes. Estimates of inferred and hypothetical resource tonnage range from 1.7 X 1C6 to 8.5 X 106 st for two deposits. Contained RED (including yttrium) averages 0.5 pct and ranges up to 2.0 pct. Deposits are of polymineralic composition and about half of this resource comprises the heavy yttrium subgroup.

Jan 1, 2011

By W. P. Haynes

ESTIMATED United States crude-oil production during 1943 established a new annual peak of 1,500,000,000 barrels, a daily average of 4,118,000 barrels. This would be an increase of 315,000 barrels per day, or 8 per cent over 1942 and 7 per cent over 1941, the previous peak. During the first ten months of the year, production jumped from 3,782,000 barrels per day in January to 4,400,000 in October. Available data for the last two months of the year indicate a leveling off of this trend, with daily rates slightly above 4,400,000 barrels.

Jan 1, 1944