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By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT: As part of an overall study of properties and processes influencing consolidation of oil sands fine tailings resulting from different extraction processes, self-weight consolidation tests were per-formed. Fourteen 2 m and 1 m high standpipe tests were instrumented to monitor the rate and magnitude of consolidation of seven fine tailings materials. Tests provided valuable information about the variation of consolidation related to differences in fine tailings material properties that result from a change in bitu-men extraction process (caustic versus non-caustic). In addition, the effect of adding a coagulant to caustic fine tailings was measured. Test results are presented and discussed in terms of consolidation rate long-term volume decrease, compressibility, and downward drainage. Non-caustic fine tailings had fasterinitial consolidation, which is important in tailings ponds for reducing storage capacity and returning decant water at a faster rate to the extraction plant. Similar results were obtained for caustic fine tailings with a coagulant addition. However, long-term settlement of the different fine tailings appears to con-verge to a similar value over time because it is then governed by effective stress.

Jan 1, 2011

By S. M. Smouse

Total world energy consumption is projected to continue its strong growth of recent years. Because coal is the most abundant fossil fuel, it will likely remain an important energy source, particularly for power generation, into at least the early years of the next millennium. Clean coal technologies are available today that can economically reduce air pollution, primarily SO2 NOx and particulates, and for the higher efficiency technologies, CO2, from power generation. U.S. Department of Energy analyses show that the adoption of clean coal technologies could decrease carbon emissions worldwide while creating a strong export market with attendant creation of jobs in the U.S.

Jan 1, 1998

By J Zhou

Based on the mineralogical characteristics and mineral processing techniques required, gold ores can be classified into 12 types, including gold placers, quartz vein-lode ores, oxidized ores, silver-rich ores, iron oxide copper gold ores, porphyry copper gold ores, iron sulphide ores, arsenic sulphide ores, antimony sulphide ores, bismuth sulphide ores, telluride ores and carbonaceous sulphide ores. The bulk mineralogy and gold deportment of each ore type is different and may have a significant impact on ore processing and metal extraction. This paper summarizes the bulk mineralogy and gold deportment in some major types of gold ores and discusses the potential impact of gold deportment on gold metallurgy.

Jan 1, 2011

By J. D. Miller

Fluid flow phenomena and therefore the flotation efficiency of air-sparged hydrocyclone (ASH) flotation are strongly dependent on the operating and design variables such as air flow rate, slurry flow rate, underflow and overflow opening areas, percent solids in the feed, reagent levels, particle size, ASH length, etc. Time-averaged multiphase flow characteristics, as deter-mined by x-ray CT and described in a previous publication, are used to understand and explain the steady-state ASH flotation of quartz. A detailed parametric study of quartz flotation by a nominal 2-inch diameter air-sparged hydrocyclone (ASH-2C) revealed the influence of these variables on the flotation response which is discussed in terms of the multiphase flow characteristics. Thus, a phenomenological description of quartz flotation has been established to assist in the further development and utilization of the ASH technology.

Jan 1, 1995

By J. F. McIlwain

As part of its goal to minimize the requirements for critical materials, the Federal Bureau of Mines has investigated the consolidation of an iron-base superalloy (20 pct Cr, 5 pct each Ni and Mn, 1 pct each C, W, Mo, and Cb, and the balance Fe) and its modifications by powder metallurgy (P/M) techniques. Vacuum-atomized, prealloyed powder was used. Consolidation was by sintering of cold-pressed alloy powder, or by forging plus rolling or extrusion of canned powder. Several commercial lubricants were evaluated in the pressing operation. At 50-tsi compacting pressure with up to 3 wt-pct lubricant, green strengths did not exceed 1,000 psi. Powder sintered just below the solidus temperature attained a tensile strength of 69,000 psi and 4 pct elongation. Liquid-phase sintering produced higher densities, lower tensile strengths, and nil ductility. Canned powder was forged and rolled at 1,200° C, yielding a 100-hr rup¬ture strength of 9,800 psi at 815° C and a room-temperature tensile strength of >130,000 psi at 6 pct elongation. Heat treatment of modified P/M iron-base alloy containing 0.63 pct C resulted in a 100-hr rupture strength of 17,000 psi. Oxidation resistance at 805° to 815° C of the forged and rolled P/M iron-base alloy was similar to that of the cast iron-base alloy and supe¬rior to conventional stainless steels.

Jan 1, 1981

By W. M. Lupton

"Internal grinding mill entries are routinely done by mill personnel during scheduled maintenance periods. Reasons for entry include mill liner life profiles, liner inspcections and replacement and grinding media investigations. These entries require employees to adhere to safety regulations and policies including special permitting, testing, procedure-following practices and the wearing of proper personal protective equipment.A realized semi-autogenous mill entry safety hazard is the unpredicted breakage and occasional shattering of large diameter grinding media while personnel are inside. This was a concern to both media user and supflier. American Barrick's Holt McDermott Mine has improved mi l operational procedures and the media manufacturer has assisted by their developments to essentially eliminate this problem.This paper presents the improvements instituted; and the author's wish to communicate this potential hazard to other large diameter SAG ball users or potential users.INTRODUCTIONAmerican Barrick' s Holt McDermott mine is situated on Highway 101, some 70 kilometers northeast of Kirkland Lake, Ontario, 120 km east of Timmins and 90 km northwest of Rouyn Noranda, Quebec. The mine draws 160 employees from these surrounding areas to extract and process the underground ore, and recover near 60,000 ounces of gold per year. The mill department is completing it's fifth year of operation this spring.The company and the employees are proud of the safety improvements realized over the short history of the mine. Post accident/incident reviews and pro-active safety awareness programs have substantially reduced the mine's accident frequency and severity to date.One of the mill department's objectives is to provide a safe working environment for mill personnel, which includes the interior of the grinding mills."

Jan 1, 1993

By NEHA PANDEY, Sunil Kumar Tripathy, ARIJIT BISWAS

Due to the growing market of Electric Vehicles (EVs), there is a rise in battery demand. Nickel can be used as a potential element in cathode for lithium-ion batteries. Nickel can provide thermal stability, high energy density, and conductivity in cathodes of lithium-ion batteries. Low-grade chromite overburden from Sukinda mines contains less than 1 wt% of nickel, which can be utilized to extract nickel. Recovery of nickel from such low-grade overburden can help in value addition. The present study provides deeper insight into the aspects of extraction of nickel product derivatives (NPDs), mainly mixed hydroxide product (MHP), through the hydrometallurgical route. The current study focuses on extracting nickel and cobalt from a mine overburden with 0.41% nickel with major silicate gangue. MHP can be processed further for nickel sulfate production, a potential raw material for cathodes in EV batteries. The study discusses a process flowsheet to recover nickel and cobalt from overburden through atmospheric leaching with pre-calcination. It is observed that the step of pre-calcination improves the effective recovery of nickel from overburden. The leaching reactions are effective at a temperature of 90 °C and 1 atmosphere pressure. The orthophosphoric acid was used as a lixiviant for the selective recovery of nickel and cobalt from overburden. Recovery of nickel and cobalt obtained at optimum conditions is 84.0% and 39.9%, respectively. The iron impurity in the leachate solution is 1.27%. It is concluded that the process with pre-calcination along with acid leaching is effective for extracting nickel and cobalt at atmospheric pressure.

Dec 28, 2023

By Robert N. Roby

The Hornsilver lead-zinc property was examined by the Bureau in 1942 and again in 1944. A project was started on the property in April 1946 and completed in January 1947. Silver was first discovered in this district in 1883, and while complete production records are not available, it is known that a substantial tonnage of high-grade silver ore was shipped before 1887. All of the ore was mined from surface or near-surface workings. When the high-grade oxidized ore was exhausted, the district became inactive and remained so until the 1920's. In 1928 and 1929 some activity was shown in the district, but the Hornsilver mine was not reopened until November 1937. Between 1939 and 1946, the mine produced about 16,000 tons of ore of 531 ounces of gold, 283 ounces of silver, over a million pounds of load, and nerdy 2 million pounds of zinc. The property is now controlled by the Era Mining & Development Co., which has acquired the Last Chance and Ella groups of claims, in addition to the Hornsilver mine.

Jan 1, 1948

By Donald L. Everhart

The National Uranium Resource Evaluation (NURE) program since 1974 has been designed to accomplish a comprehensive coverage of the 48 conterminous States and Alaska to evaluate the total uranium resources of the USA. This resource base includes both ore reserves and potential resources. Techniques include airborne radiometric and magnetic surveys, by hydrogeochemical surveys, surface and subsurface geologic studies, and the application of improved geochemical exploration and resource assessment methods (Table 1). In brief review, the current status of each of the five basic NURE elements is as follows: In the Aerial Surveys, in the conterminous 48 states, the flying has been completed in 89 of the NTMS 10 x 2° NURE quadrangles, and is in progress in 39 more (Figure 1). Complete quadrangle data have already been open filed for 46 additional quadrangles, for a total of 174 for which data gathering is either complete or in progress. In Alaska, the flying is complete in 42 quadrangles, and quadrangle data have been open filed for 34 more, for a total of 76 (Figure 2).

Jan 1, 1979

By Claudio Luiz Schneider

Não existe na literatura formal uma descrição dos ensaios de caracterização necessários para a correta determinação de parâmetros de balanço populacional para escalonamento pelo método de Austin. As rotinas envolvidas são normalmente aprendidas em Universidades e Centros de Pesquisa que contam com engenheiros e/ou pesquisadores especificamente treinados para estes experimentos. Isso faz com que estes sistemas modernos sejam pouco utilizados na engenharia e restringe sua aplicação. Este artigo tem por objetivo estabelecer os procedimentos envolvidos na caracterização de processos de moagem e fomentar a utilização de técnicas modernas de escalonamento de moinhos de bolas nas empresas.

Aug 16, 2017

By Rogério Ruiz

Atualmente os fabricantes de equipamentos e empresas de engenharia utilizam, na sua maioria, experiência em projetos anteriores para o dimensionamento de silos, chutes, pilhas de estocagem e outros equipamentos de manuseio e estocagem para a indústria mineira. O objetivo deste trabalho é apresentar uma metodologia eficiente e mundialmente reconhecida para a solução e prevenção de problemas de fluxo de sólidos, utilizando método científico e comprovado. Os principais testes laboratoriais para obtenção de propriedades de escoamento dos materiais serão descritos. Os testes necessitam de pequenas quantidades de amostras representativas do material e os parâmetros levantados alimentam a metodologia de análise de escoamento de sólidos ou softwares de simulação numérica, e são essenciais para a correção de equipamentos defeituosos ou dimensionamento de novos equipamentos.

Aug 1, 2018

By John S. Berber

To improve the economics of low-temperature carbonization of coal, the Bureau of Mines is conducting research on the upgrading of the product tar to marketable chemicals. This report describes experiments on the catalytic hydrodealkylation, followed by catalytic vapor-phase oxidation of the dealkylate to phthalic and maleic anhydrides, of mixed residues from the urea adduction of lignite-neutral oil fraction and on the catalytic thermal dealkylation of high-boiling tar acids. The hydrodealkylation experiments were conducted at pressures from 1,000 to 1,750 psig and at temperatures from 600° to 1,000° F. The oxidation was, in all cases, at atmospheric pressure and 9500 F. Maximum yield of maleic anhydride, based on the liquid feed to the hydrodealky1ation unit, was 12.2 percent at 750° F and 1,500 psig; that of phthalic anhydirde was 6.9 percent at 650° F and 1,500 psig. Maximum yield of combined anhydrides was 18.8 percent at 650° F and 1,500 psig. The non-dealkylated feed material, upon oxidation, yielded 8.9 percent and 3.8 percent maleic anhydride and phthalic anhydride, respectively.

Jan 1, 1967

By M. Proulx

"RÉSUMÉ Le diagramme ternaire Al2O3-Sr-Y est un nouvel outil servant à l’exploration de gisements de sulfures massifs volcanogènes (SMV) archéens. Le diagramme permet de discriminer entre les roches volcaniques à minéralisations à zinc dominant (domaine Zn+) et celles à minéralisations à cuivre dominant (domaine Cu+), ainsi que les roches volcaniques ayant subi une chloritisation hydrothermale pouvant aboutir à la formation de chloritites associées aux cheminées d’altération (domaine Cl+). Ces trois domaines délimitent des zones d’influence géochimique ou d’empreintes hydrothermales résiduelles ou fossiles produites par les cellules de convection hydrothermales générées par des magmas. Le diagramme permet aux sociétés d’exploration de déterminer de façon peu coûteuse la fertilité potentielle des roches volcaniques archéennes en ayant recours à leurs bases de données et aux résultats de leurs analyses de terrain, sans aucune manipulation des données. Le diagramme ne s’applique pas aux SMV aurifères.ABSTRACT The tertiary diagram Al2O3-Sr-Y is a new tool to explore Archean volcanogenic massive sulphide (VMS) deposits. The diagram can be used to discriminate between the volcanic rocks where zinc is the dominant mineralization (Zn+ domain) and the rocks where copper is the dominant mineralization (Cu+ domain), as well as the volcanic rocks that were subjected to hydrothermal chloritization that could have led to the formation of chloritites associated with alteration chimneys (Cl+ domain). These three domains define the zones of geochemical influence, or residual or fossil hydrothermal footprints produced by hydrothermal convection cells generated by magmas. Exploration companies can apply the diagram to determine, at low cost, the potential fertility of the Archean volcanic rocks by using their databases and the results of their field analyses, without any data manipulation. The diagram does not apply to gold-bearing VMS deposits."

Jan 1, 2015

By Sam S. Arentz

Storm King Mines began with the concept that the resource potential of thick and steeply pitching seams of the Grand Hogback region of Colorado could be mined profitably. Two large tracts of private land (fee coal) were acquired; approximately 23.8 km2 near Glenwood and 16.2 km2 near Meeker. Figure 1. Although both properties have substantial coal reserves, one has several distinct advantages in developing a competitive mining operation. Table 1 illustrates these advantages. Among the most important considerations from an economical point of view are proximity to railroad, highway, labor force, quality of coal, seam thickness, and source of water. As can be seen, Storm King Mines' property is adjacent to the main line of the D & RGW Railroad, 1-70, and the Colorado River. The cities of New Castle, Glenwood Springs, Silt, Rifle, Carbondale, and Parachute are within short commuting distances and have available skilled labor.

Jan 1, 1983

By Witold J. S. Ostrowski

The shaft structure being part of an underground mine, depends on programned functional duties, and on geological and hydrological conditions. The majority of Canadian metal mine shafts are in hard competent igneous rocks, which are in an elastic state of equilibrium around the excavation. Others penetrate soft sedimentary or very weak water-bearing rock formations in which the equilibrium varies from plastic to hydrostatic. Knowledge of how to interpret the underground conditions, determine acting forces and design proper structures is essential for the production and safety of the future mine.

Jan 1, 1973

By James M. Tantalla, Roderic A. Ellman, W. Allen Marr, Scott R. Bamford

"Construction of the powerhouse for the Willow Island Hydroelectric Project required a 100-ft deep excavation inside the limits of a cofferdam and embankment-seepage cut-off wall through soil and rock adjacent to the Ohio River. Portions of the rock had preexisting weak plans and slickensided surfaces with low frictional strength. Stability analyses were performed for critical sections of the excavation to evaluate the stability of the soil slopes and rock cuts using buckling, tension crack, and limit equilibrium analysis techniques. Loading conditions included the 100-yr and intermediate floods, normal pool, sudden drawdown, and seismic design conditions.Stability analyses indicated adequate factors of safety for soil slopes and for rock cuts through the landside embankment sections. However, the results of deep-seated stability analyses through the rock supporting the riverside cellular cofferdam indicated unacceptable factors of safety. Consequently, the riverside portion of the excavation required measures to increase stability. Long, high-capacity rock anchors and deep dewatering wells to lower the site piezometric head were chosen for this purpose.Thirty high-capacity rock anchors were installed on the upstream, riverside, and downstream sides of the cofferdam rock cut. Required rock anchor loads varied from 1,968 to 2,074 kips. The designed anchors consisted of multiple, seven–wire strands with up to 59 strands per anchor. Bond lengths used an allowable bond stress of 100 psi based on the rock bond measured with pull-out tests. Maximum bond and anchor lengths were 50 ft and 140 ft, respectively. Measurements of forces in selected strands and displacements of the excavation showed excellent performance."

Jan 1, 2017

By Donald C. Strimbeck

The Bureau of Mines, U.S. Department of the Interior, is conducting research and development on a coal-burning gas turbine. This work includes the development of (1) turbine blades resistant to coal ash erosion, (2) equipment to feed coal under pressure to a turbine, (3) an efficient combustion system, and (4) equipment to remove coal ash from the gases that drive the turbine. Initial emphasis is being placed on testing the first turbine ever equipped with blades designed specifically for use with coal as the fuel. Operating tests with this turbine are now in progress. This paper describes the Bureau's coal-burning gas turbine development program and progress on this operating test.

Jan 1, 1964

By Philip W. Johnson, Charles D. Haynes

"Abstract - The coalbed methane industry has become a prominent source of domestic natural gas, with its technology having evolved over the past 30 years. Whereas most coalbed methane wells are able to produce without major interruption over their economic lives, wells operating in an underground mining area are subject to being mined-through. If mine-through occurs, the productivity of the well is at least compromised, and may even be terminated. The economic consequences of mine-through may be relatively simple if mineral ownership and extraction rights are common for the coal and coalbed methane. However, if ownership is not common and a superior coalbed methane lease exists, the coalbed methane ownership must be compensated for lost production caused by mine-through. This paper presents a relatively straightforward method to calculate the value of the lost production caused by the mine-through. It uses technology from mining and petroleum engineering, as well as simple economics and financial management techniques.Sommaire - L’industrie de la production de méthane houiller est aujourd’hui une source importante de gaz naturel domestique dont la technologie a considérablement évolué au cours des trente dernières années. Bien que la plupart des puits de méthane houiller peuvent être mis en production durant l’entièreté de leur vie utile sans interruption majeure, les puits implantés en périphérie de mines souterraines sont sujets à être recoupés par ces dernières. Un tel recoupement peut compromettre, ou même mettre fin à la production d'un tel puits. Les conséquences économiques du recoupement par une mine souterraine peuvent être relativement simples quand les droits miniers et les droits d’extraction sont détenus en commun pour le charbon et le méthane houiller. Si toutefois ces droits ne sont pas détenus en commun et qu’il y a eu octroi d’une concession de méthane houiller de qualité supérieure, les détenteurs du méthane houiller doivent être compensés pour la perte de production résultant du recoupement par une mine souterraine. Cet article présente une méthode relativement simple pour calculer la valeur des pertes de production suite au recoupement par une mine souterraine. Cette méthode fait appel aux technologies de l’industrie minière et pétrolière ainsi qu’à des techniques simples d’économie et de gestion financière."

Jan 1, 2006

By A. B. Fly

This paper presents the equipment and techniques developed to mine subsurface mineral deposits through 16 inch bore holes entirely by hydraulic methods. Use of this equipment for excavating large cavities in oil and water well producing zones is discussed. Results of surface experiments using high pressure jet streams of water to determine the cutting rates of materials are outlined. Various basic shapes of subsurface excavations that can be mined with the equipment are illustrated and discussed. An example of the cost of mining by this method is presented. Problems encountered in the field operations led to the development of a new explosion type slurry pumping system and related slurry handling equipment.

Jan 1, 1969

By Erle C. Donaldson

Bureau of Mines engineers examined the chemical and biological treatment of sewage water designed in one case for reuse and in another for subsurface injection. In the first case discussed, approximately 6 million gallons per day of sewage are treated by the activated sludge process followed by tertiary treatment that includes ion exchange. The renovated water is used in the industrial complex. Liquid industrial waste is sent to a waste disposal facility where it is treated for injection into a deep subsurface formation. In the second case, a community of 3,000 people is using a lagoon sewage treatment system followed by subsurface injection of t- treated effluent. Subsurface disposal is used to avoid growth of algae and weeds in a nearby lake to which the treated effluent was originally discharged. The renovation of municipal water for reuse provides a source of water for industries in a semiarid region and may also provide a source for domestic use in densely populated regions where domestic water requirements have priority over industry needs. In addition both waste treatment systems provide examples of the use of subsurface waste disposal to avoid pollution of surface streams.

Jan 1, 1971