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By J. P. Allen

Cobalt, nickel, and manganese can be recovered quickly, cleanly, and selectively from cobalt-rich manganese crust by leaching in dilute acid solutions in the presence of hydrogen peroxide. Common selective precipitation methods can then be used to recover these metals from the leach liquor. The leaching reaction produces only oxygen as a byproduct, and the waste residue from leaching was tested and found to be non-hazardous under existing EPA specifications. The leaching process is effective in either fresh water or seawater. This research is a part of the Bureau of Mines program to identify the mineral resources of the Exclusive Economic Zone and devise methods for recovering their valuable components.

Jan 1, 1990

By James S. Wroth

The Act of Congress approved June 25, 1926 (Public Act 424, 69th Congress), authorized joint investigations by the U. S. Geological Survey and the U. S. Bureau of Mines to determine "the location, extent, and mode of occurrence of potash deposits in the United States." The particular deposits selected for exploration were the extensive rock-salt formations underlying large areas in western Texas and southeastern New Mexico, from which potash salts had been identified in the cuttings and sludges from oil wells drilled with cable tools. The evidence of these sludge samples was qualitative only and beyond definitely proving the presence of potash salts in the salt beds, gave little clue to the possible size, richness, or extent of the potash occurrences.

Jan 1, 1929

By C. M. Campbell

The Inconceivable Wealth propaganda goes on apace. Premier King, at Vancouver, has stated that we still have, untouched, natural resources, "beyond the wildest dreams." Principal Currie, in an address before the Canadian Society in New York said that Canada's resources, "are as yet merely scratched and it is not possible to compute her almost fabulous natural wealth." Mr. Meighen, in the last election campaign announced that, "under the providence of God, Canada is more richly endowed, perhaps, than any other country in the world." Four years ago a despatch was sent to Premier King "on behalf of" this Institute advising him that "Inconceivable Wealth" in minerals in this country was assured. This was made as a statement ~f "incontrovertible fact." Specifically, this despatch stated that this wealth was on such a scale that the mining industry would in the future lead all others in this country. This inventory is still in effect as far as this Institute is concerned.

Jan 1, 1926

By P. N. Anyalebechi

"The effects of solidification rate, initial melt hydrogen concentration, and grain refining on porosity formation in aluminum alloy 2024 have been investigated with unidirectionally cooled laboratory-size ingots. The ingots were prepared from melts containing hydrogen concentration of 0.059-0.27 cm3/100 g and solidified at 0.2-37 °C/s. As expected, the amount of porosity, average pore size, and pore number density increased with increase in melt hydrogen concentration and decrease in solidification rate. However, the effect of solidification rate was greater at the very low melt hydrogen concentration (0.059 cm3/100 g). These results are consistent with reported effects of solidification rate and melt hydrogen content on porosity formation in other aluminum alloys. Interestingly, addition of grain refiner slightly increased the amount of porosity and the average pore size, especially at solidification rates above 1°C/s. IntroductionIn shaped castings and wrought products fabricated from ingots, billets, bars, or slabs of aluminum and its alloys porosity formation is a problem. This is because it compromises their tensile strength, fracture toughness, and fatigue properties [ 1-18]. The pores are usually the crack initiation and propagation sites [6,8,9] and the largest pores tend to dictate the fatigue life of the aluminum products [9,10,14]. Porous regions within an aluminum product probably yield first due to the reduced tensile load bearing capacity, causing the concentration of the strain near the voids which subsequently results in premature fracture. In aluminum alloy ingots, billets, bars and slabs porosity formation is particularly problematic because of its persistence through fabrication and potential for reappearance or exacerbation during subsequent thermal treatment processes before and/or after fabrication [19]. In fact, persistence of microporosity is a serious problem in large thick plates of wrought aluminum alloy products that must be rolled from correspondingly large direct-chill or electromagnetic cast ingots. Some of these thick plate products are machined into large aircraft components that are required in service to withstand multi-directional stresses and to possess high fatigue strength, fracture toughness, resistance to stress corrosion cracking, and strength in the short-transverse direction [1,20]."

Jan 1, 2011

By R. Feenstra

In the course of time, an increasing number of investigations on jet cutting all kinds of material, such as rocks1, 2, 3, metals4, 5, and wood6 have been reported to serve various applications. This paper deals with one particular application of jets, viz deep-well drilling for hydrocarbon exploration and production. A number of papers have been published on this subject 7, 8, 9, some of which refer to jets purposely containing abrasives, termed 'jetted particle drilling'7. Since such abrasives complicate fluid handling considerably and do not appear to be absolutely necessary for making hole we have restricted ourselves to conventional drilling fluids. A large part of our investigation has been performed with the aid of three laboratory-type drilling machines, which permit tests on both micro-bits (12 in) and full-scale bits (62 - 9 5/8 in). In view of the application of jets in deep wells, care has been taken to simulate hydrostatic pressures as they exist in the field on the hole bottom. These have been found to have a major effect on the bit-penetration rate for various drilling fluids. Following experiments with single nozzles, laboratory bits have been designed, improved further and developed for field use. Field runs on 9 5/8 in bits, using conventional equipment and pumps, served to verify the feasibility of the jet drilling concept. Further efforts are evidently needed to evaluate the jet drilling method. It is encouraging that one of these10, a field test programme, is supported by a number of oil companies jointly. Such a combined effort is of paramount importance to evaluate and develop this new method of drilling to its full potential in a reasonable period of time. This paper aims to contribute to that ultimate goal.

Jan 1, 1974

By Arthur E. Morris

Fifty years ago when Professor Yazawa began his career, the field of process simulation and modeling was in its infancy. Since then, tremendous progress has been made in our ability to model metal production flowsheets from mine to refined metal. This progress has come about by parallel developments in basic understanding of process chemistry and in computational techniques, This paper will review the progress made in process understanding and modeling in lead, zinc, and copper metallurgy from its inception to the present, and the role of Professor Yazawa's work in furthering this progress. Specific examples will be given for the sintering of lead concentrates, slag fuming, zinc concentrate roasting, flash smelting of copper, and pyro-extraction of zinc. Factors limiting further progress will be described.

Jan 1, 2003

By A. E. Back

A method has been developed in the laboratory for successfully treating titaniferous magnetite ore from the deposit at Iron Mountain, Wyo. The ore is roasted with 15 percent sodium carbonate to convert the vanadium to a water-soluble form and fix the soda for the subsequent electric-smelting step. Approximately 90 percent of the vanadium is recoverable in a product assaying 80 percent V2O5. The leached calcine is briquetted and smelted in a graphite-lined electric-arc furnace. Substantially all of the titanium is recovered in a soda slag, assaying 60 percent TiO2 and 2 percent Fe, which can be upgraded to 75 to 80 percent TiO2 by leaching with dilute sulfuric acid. The upgraded slag could be utilized for the production of titanium dioxide pigments or titanium tetrachloride. About 90 percent of the iron is recovered as pig iron, containing only minor amounts of vanadium, titanium, and sulfur. The high TiO2 slag compares favorably with slag containing about 70 percent TiO2 being produced by the Quebec Iron & Titanium Corp. at Sorel, Quebec. The data obtained from this investigation indicate that a feasible process has been developed for treating Iron Mountain ore, and larger-scale testing is warranted to develop engineering data for the ultimate utilization of this deposit as a source of titanium, iron, and vanadium. There are adequate supplies of basic raw materials, electric power, water, sodium carbonate, coal, and petroleum products within fairly short distances of Cheyenne and Laramie, Wyo., the nearest cities and probable plant- and labor-supply points.

Jan 1, 1952

By K. C. Vincent

In the course of, investigation of domestic manganese-mineral occurrences, examining engineers of the Bureau of Mines collected 2-ton lots of ore from properties in the Cleveland-district, Idaho. As only one of the ores was high enough in grade for direct marketing to-producers of ferromanganese, ore-dressing concentration methods were investigated to determine their amenability to treatment. High-grade ore. (38.7 percent Mn) from the Idaho Manganese Mining Co. was taken from a replacement deposit in limestone consisting of several horizontal beds 1 to 5 feet thick, about 1 mile northeast of Cleveland. The manganese minerals occur as an intimate intergrowth of manganese oxides, containing minor amounts of limonite, ?quartz, and calcite as rather fine inclusions. However, the major contaminants are claylike products of rock decomposition, which can be eliminated by thorough washing of the ore at relatively coarse sizes. The Hot Spot property is 1 mile south of Cleveland. The ore occurs as a replacement deposit of medium-grade- ore in limestone, .The sample taken by the Bureau of Mines assayed 26.0 percent Mn. The manganese minerals consist of nodules, principally pyrolusite with some psilomelane and manganite embedded in wad.' The low-grade wad, containing manganese and siliceous minerals in intimate association, was easily rejected by washing.

Jan 1, 1952

By T Baumgartl, L Zhou, D Mulligan, L Huang

The rapid production and accumulation of mineral processing wastes in the environment can present serious threats to environmental quality and human health. Phytostabilisation with native plant ecosystems is, in many cases, a preferred option for rehabilitation of mine waste storage facilities. However, much of the literature has focused on species selection in short-term experiments to test their suitability under the often extreme chemical conditions in the wastes without addressing the fundamental requirements – ie hydrogeochemical stabilisation and functional root zones. As a result, successful examples of phytostabilisation of mine wastes such as base metal tailings have been rare, especially if success is defined as meeting the completion criteria of non-polluting and sustainable land system at rehabilitated sites. Conventional capping options to isolate reactive tailings/wastes by using physical break and/or sealing layers are often not reliable in the long term (particularly under semi-arid climatic conditions) and, in many cases, they may not be feasible in the field due to the large areas to be covered and the lack of adequate suitable materials at mine sites. By using sulfidic tailings as an example, we have proposed a new paradigm for phytostabilising mine wastes – ecologically engineered pedogenesis in tailings involving accelerated physical, chemical and biological weathering of tailings minerals to achieve hydrogeochemical stabilisation and the development of soil functions, soil horizons and functional root zones.Ecologically engineering functional root zones firstly requires controlling geochemical reactivity in the wastes (ie hydrogeochemical stabilisation), which can cause polluting effects in the root zone and plant toxicity. By means of ecological engineering, in situ weathering of primary minerals (eg pyrites) in tailings may be accelerated by adding functional materials (eg functionalised biochars and organic matter) in the waste slurry during the process of deposition. This will remove or diminish key risk factors (eg potential acidity in tailings and elevated soluble heavy metals) in the solid phase, before placing growth media for reconstructing root zones and transplanting/sowing target plant species. However, much of the acidity, soluble metals/metalloids and other salts would be transported out of the solid phase into the wastewater, which can be addressed by on-site water treatment facilities during mine operation. The trajectory and state of engineered pedogenesis in the weathered tailings may be manipulated to provide specific soil horizons within future root zones that are dynamically evolved toward fully functional soil subsystem within rehabilitated plant ecosystems.CITATION:Huang, L, Baumgartl, T, Zhou, L and Mulligan, D, 2014. The new paradigm for phytostabilising mine wastes – ecologically engineered pedogenesis and functional root zones, in Proceedings Life-of-Mine 2014 , pp 663–674 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By F. R. Jones, B. W. Taylor, A. R. MacPherson, L. J. Lamb

"The Lake St. Joseph Iron Deposit is in Northwestern Ontario. Exploration to date by Steep Rock Iron Mines Limited has indicated an ore reserve of 683 million long tons. Metallurgical investigations have proved that suitable oxide pellets and/or superconcentrates can be economically produced from this ore. Studies of the Lake St. Joseph iron ore deposits have covered the period 1956-71, and have embodied applications of the improvement in mining and processing technology over this period. Market demand in the early 1960's for high-grade oxide pellets as a replacement for natural iron ores for the blast furnace first drew attention to the potential of the Lake St. Joseph deposit. The current market trend toward utilization of sponge iron to replace steel scrap as feed to electric furnaces and cupolas now suggests that the deposit can better be exploited as a prime source of superconcentrates."

Jan 1, 1972

Strips of AA6111 automotive alloy were cast on a horizontal single belt strip casting simulator, Pure copper and carbon steels substrates plasma sprayed with different coatings for improving the strip surface quality, were used as chill moulds, Experimental studies revealed that a graphite coating provided the greatest benefit in achieving good surface quality. The interfacial heat fluxes during solidification of AA6111 strip were calculated by the IHCP method (Inverse Heat Conduction Problem). Temperature variations and cooling rates within the strips were then calculated through numerical simulations based on the time-dependent heat fluxes obtained by IHCP, The effects of casting parameters, including casting temperature and strip thickness, on interfacial heat fluxes, cooling rates and microstructures, were investigated, Although the maximum interfacial heat fluxes on the chill copper substrate were much higher than the results obtained from the steel substrates, the solidification times of the melts were mainly determined by strip thickness. Very fine equi-axed grains were obtained for both 1.2mm and 2.5mm thick strips thanks to the rapid extraction of heat, and effective grain refinement.

Jan 1, 2005

By Kevin P. Plucknett, Z. Memarrashidi

"In the current work, factors influencing the corrosion mechanisms of TiC and Ti(C,N) based cermets are reviewed. Cermets were typically prepared with 30 vol.% of metal binder, in the form of various in-situ reaction-formed Ni3Al alloys. Commercial WC-Co hardmetals were also examined as baseline materials. The assessment of corrosion involved a variety of electrochemical measurements, including open circuit potential and potentiodynamic polarisation. The corrosion potential and current density were determined, following Tafel extrapolation, allowing estimation of the corrosion rates. Post-corrosion characterisation involved scanning electron microscopy analysis and associated energy dispersive X-ray spectroscopy of the sample surfaces. It is demonstrated that the primary corrosion mechanism for this type of cermet is dissolution of the metallic phase during oxidation attack, and thus this response can be expected to increase with the amount of binder in the cermet, although degradation can be subtly affected by composition (i.e. alloy composition, C:N ratio, impurities in the ceramic phase, etc.) and test procedure (i.e. aerated vs. de-aerated electrolytes). It was observed that addition of N content into the ceramic phase is beneficial to the corrosion characteristics of TiC based cermets, through significant refinement in the grain size of the hard phase. Similarly, elimination of impurities, such as W in selected TiC powders, also improves the corrosion resistance.INTRODUCTION Cermets are prepared using the combination of a hard, high elastic modulus ceramic phase with a ductile, high toughness metallic binder. This pairing of hard and ductile components ensures wide application of cermets in demanding wear environments. These materials are consequently used industrially in both bulk and coating form. The most common example of such a composite system is based on the use of tungsten carbide with a cobalt-based binder (WC-Co), which has been widely examined over the past 80 years. However, while WC-Co has been shown to exhibit an excellent combination of high strength and wear resistance, the corrosion and high temperature properties of this material are relatively poor. In addition, WC-Co possesses a high density (~13–14 g/cm3), which makes it a less desirable option when the component mass is a design factor (i.e. use in aerospace). In particular, the aqueous corrosion response of WC-Co limits its use in wear environments where combined corrosive degradation may occur (i.e. tribo-corrosion scenarios). Alternate cermet systems are therefore being actively developed due to these performance limitations."

Jan 1, 2017

By F. Baczek, S. S. Rocks, D. Chaiko, C. Eyzaguirre, S. Asihene, T. Walters

The majority of efforts to improve primary copper sulfide leaching have focused on solution chemistry, temperature, O2 pressure, ultra-fine grinding, the use of catalysts, etc. Historically, very few studies have focused on the solid/solution interface. A new, patent pending approach to catalyzed, copper sulfide leaching has been discovered by FLSmidth that enables manipulation of the 2-D semi-conductor properties of chalcopyrite surfaces to the benefit of higher electrochemical reactivity. Copper dissolution rates are then further accelerated by incorporating a Stirred Media Reactor (SMRt) into the process. By using minute amounts of Cu2+ to "pre-activate" chalcopyrite, leach times have been reduced from >20 hours with incomplete Cu dissolution to <2 hours with 98+% Cu dissolution at 80°C. The pre-activation process takes only minutes to complete at temperatures of 80°C or less. The total atmospheric leaching process, incorporating the pre-activation and Stirred Media Reactor is compatible with existing SX/EW processes. Results of batch leach testing are presented and possible mechanisms are discussed.

Jan 1, 2015

By I M. Platten, Y Xie, R-M F. Bell, S C. Dominy, L E. Howard, R C. A Minnitt

For any resource evaluation program, the collection and processing of representative samples for assaying is critical. Sampling, sample preparation and assay protocols must be designed to suit the style of orebody in question. The a priori need is for the characterisation of mineralisation type(s) and domain definition. The proportion and size of gold particles has a direct impact on the effectiveness of sampling protocols employed. Mineralogical studies focusing on gold particle deportment, size and distribution are required. Key issues are the presence of gold particle clustering and proportion of coarse versus fine gold. High-resolution X-ray computed tomography (HRXCT) is a radiographic technique that produces high-resolution 3D computerised models of in situ objects based on density distribution. The ævirtualÆ specimens are made up of voxels, the 3D equivalent of pixels each assigned a grey value based on X-ray absorption. This paper presents the results of recent research on the imaging of in situ particles in coarse gold-bearing ore samples from the Nalunaq mine, southern Greenland. The samples used were previously well-characterised through mineralogical and metallurgical testing, and serve to test the HRXCT methodology. Gold particle size and distribution in the context of the sampling liberation diameter was investigated.CITATION:Dominy, S C, Platten, I M, Howard, L E, Xie, Y, Bell, R-M F and Minnitt, R C A, 2012. Determination of the sampling liberation diameter in a high-grade coarse gold ore by high-resolution x-ray computed tomography, in Proceedings Sampling 2012 , pp 161-170 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By E. Swartzman

This paper presents a general re-view of the various methods of briquetting coals, with and without the aid of a binder, with special reference to the production of a suitable briquette from Nova Scotia 'fines' for re-blending with industrial coal. From the economic and technical viewpoints, either small stoker-sized briquettes made with about 4 per cent asphalt in standard low-pressure double-roll presses, or briquettes made without binder in high-pressure double-roll presses, appear to be the most reasonable solution at present.

Jan 1, 1959

By E Corpuz, J Weissman, S Winter, R Evans

The surface-to-inseam (SIS) directional drilling technique has been utilised at Oaky Creek Coal for more than a decade to predrain both the Oaky No 1 and Oaky North mining areas. The cumulative drilling program constitutes a total of 140 lateral and 200 vertical holes, and 405 km of lateral drilling.The use of SIS gas drainage has been successful with the following site-specific benefits being recognised:ability to drain German Creek seam gas contents to residual gas levels of new mining areas within an 18-month period from commencement of well productionstructural geological verification of the mine design well in advance of development mining occurring in an areaability to conduct successful predrainage of the overlying Aquila seam to reduce subsequent goaf emissions.Appropriate and up-to-date geological knowledge during the design and drilling process is a significant influence to achieving success. Vertical production wells need to be located in a position that is most effective to remove water from hole. The lateral hole should not include intersections with significant geological structure.SIS drilling provides continuous seam roof/floor data to help define seam geometry and locate geological hazards with high accuracy. In faulted ground and with variable seam gradients, SIS data can resolve geological ambiguities from seismic sections and enhance seam correlation that would otherwise be available only from discrete and closely-spaced infill vertical exploration drilling.Here, we review some examples of SIS configurations and practice to highlight key learnings in drilling long inseam holes (up to 1900 m per arm) ahead of development and mining. Aspects on prerequisites, evolution of network design, tolerances and drainage outcomes in a variety of geological situations are discussed as technical basis towards a viable and effective SIS drilling program.CITATION:Corpuz, E, Evans, R, Weissman, J and Winter, S, 2015. Surface-to-inseam (SIS) drilling at Oaky Creek coal mine – SIS design aspects and drilling environment, in Proceedings The Australian Mine Ventilation Conference, pp 93–104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By Reichmuth, Donald R.

Most brittle solids are relatively weak in tension and this weakness can be very significant in determining their performance in structures and excavations. Consequently, accurate knowledge of the tensile strength of brittle materials has long been recognized as important. In the past, measurements of the tensile strength of materials such as concrete, ceramics, and particularly rock have been hindered by problems encountered in fabricating test specimens and in accurately loading them. These difficulties have resulted in a scarcity of published tensile strength data. This can be readily seen in tabulations such as Wuerker&apos;s "Annotated Tables of Strength and Elastic Properties of Rocks.

Jan 1, 1968

By J. Markussen

The Falconbridge Matte Leach Plant was based on leaching Ni-Cu matte with strong hydrochloric acid in rubber lined equipment. It operated from 1968 to 1983 as a precursor to Nikkelverk&apos;s present C12 Leach. The process comprised two S.X. systems. NiC12.4H20 crystallization, crystal drying, NiC12.H20 pyrohydrolysis and HC1 gas recovery. The naphtha fired fluid bed pyrohydrolyzer produced granular NiO, subsequently reduced with H2 to granular nickel for sale. The development and operation of the pyrohydrolyzer are described

Jan 1, 1991

By Oliver C. Ralston

Fluorescence is of growing interest to the mineral industry because certain minerals may be detected thereby and because, as shown in figure 1,4/ many minerals (natural or synthetic) are needed in tubes and lamps. The use of fluorescent lighting is expanding, and large numbers of lamps of many sizes and shapes are being made and used in works, factories, stores, offices, homes, and in photography. Fluorescent tubes, as distinguished from clear tubes filled with neon, argon, or other rare gases through which a current of electricity passes, fluoresce owing to specially, selected and prepared minerals placed in the tubes. Luminous chemicals and paints also contain special minerals and are used in similar applications; therefore, these also will be considered in this report. Although the quantity of minerals (in tons) that are used for fluorescent purposes is small, and probably will continue to be so, this use is significant because it exemplifies a requirement for "pure" minerals in which a trace of contaminant as" minute" as one part in ten million may distinguish between the acceptance or rejection of a particular material. This extreme purity makes synthetic minerals almost essential, and natural mineral&apos;s are now little used.

Jan 1, 1944

By Jeffrey M. Listak

The Bureau of Mines has conducted a rock mechanics study to monitor deformation of near-seam strata above a longwall panel in the Pittsburgh Coalbed. The primary goal was to determine the height of caving immediately behind advancing longwall face supports. This study, although site specific, provides information on the caving mechanism associated with longwall extractions so that strata behavior and its interaction with longwall face supports can be better understood. Two holes were drilled, approximately 550 ft apart along the center line of a longwall panel, from the surface to the coalbed approximately 650 ft below. Various downhole geotechnical instruments were used to monitor strata deformation. In addition, surface elevation surveys were conducted to differentiate between surface and subsurface activity. This report discusses the caving characteristics of the strata as the longwall panel approached and passed beneath the boreholes. Physical property data are also presented to demonstrate the relationship between caving behavior and local geology. Data show that immediate caving of strata above the longwall face occurred at a height less than 23.5 ft and that strata behavior above longwall extractions is highly dependent upon lithology, with major disturbances occurring at weak lithologic zones.

Jan 1, 1986