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By W. G. Davenport

Chapter 1 showed that flash smelting is a key step in extracting copper from sulfide ores. It also showed that there , are two versions of flash smelting: (a) Outokumpu flash smelting, which uses oxygen-enriched air blast and injects dry feed downwards into a hot furnace (b) lncoflash? smelting, which uses industrial oxygen blast and injects dry feed horizontally into a hot furnace. This chapter describes Outokumpu flash smelting.

Jan 1, 2001

Role of Bubbles in the Action of Flotation Agents

Sep 13, 2010

By William H. Pomroy

The Bureau of Mines, through a 4-year program of combined in-house and contract research, has developed the necessary hardware and software technology to provide rugged, reliable automatic fire protection for surface mining mobile equipment. One element of this program was a continuing effort to help foster rapid mining industry acceptance of the technology by keeping end user costs reasonable. This report is an analysis of the economic impact of surface mining mobile equipment fires and the cost benefit of utilizing automatic fire protection systems to abate these losses.

Jan 1, 1982

This is the third in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The second report gave the same data for motor gasolines sold during the summer of 1936)4/ As was the case with the first cooperative gasoline survey, reports were received for some areas from only one company and in other areas from two companies that did not in all instances report on the same brands of gasoline. In still other areas reports were received from five or six companies on the same brands of gasoline. Thus, it can be seen that data on gasolines are unequal in regard, to the number of reports that were averaged in calculating the data shown in table 1. The data from the Pacific Coast were averaged by the Pacific Coast technical group before submission and are published exactly as they were submitted.

Jan 1, 1937

By Thomas M. Barczak

This report chronicles the historical development of longwall mining in the United States and speculates on future developments to the turn of the century. Five eras of technological development during the modern period are described and analyzed. These eras discuss the development of (1) mechanized extraction, (2) self advancing roof supports, (3) high capacity roof supports, (4) shield supports, and (5) system automation. Current trends are analyzed in terms of: longwall utilization, production capability, support capacity, face widths, and new technological developments. From these analyses, the future of longwall mining to the year 2000 is speculated. It is concluded that longwall mining will continue to grow in importance during the next decade and that the next major technological milestone will be the realization of a fully automated longwall mining system.

Jan 1, 1992

This is the third in a series of reports on properties of commercial motor fuels, made in accordance with a cooperative agreement between the Cooperative Fuel Research (C. F. R.) Committee and the Bureau of Mines of the Department of the Interior. The first report gave data on motor gasolines sold during the winter of 1935-36.3/ The second report gave the same data for motor gasolines sold during the summer of 1936)4/ As was the case with the first cooperative gasoline survey, reports were received for some areas from only one company and in other areas from two companies that did not in all instances report on the same brands of gasoline. In still other areas reports were received from five or six companies on the same brands of gasoline. Thus, it can be seen that data on gasolines are unequal in regard, to the number of reports that were averaged in calculating the data shown in table 1. The data from the Pacific Coast were averaged by the Pacific Coast technical group before submission and are published exactly as they were submitted.

Jan 1, 1937

By B. J. Moore

The Bureau of Mines has estimated helium resources of the United States at 727 billion cubic feet as of January 1, 1979. These resources are divided into four categories in decreasing degrees of assurance of their existence: (1) Helium in storage and in measured natural gas reserves, 185 billion cubic feet; (2) helium in indicated natural gas resources, 150 billion cubic feet; (3) helium In hypothetical natural gas resources, 186 billion cubic feet; and (4) helium in speculative natural gas resources that makes up the remaining 206 billion cubic feet. The identified helium reserves, which are made up of that in measured and indicated natural gas categories, are further divided into depleting, non- depleting, and stored classifications. The depleting resources are those that are associated with natural gasfields that are, or will be, produced for the natural gas they contain. All of the helium in undiscovered natural gas resources are included in this classification. These depleting resources comprise 600 billion cubic feet of the total resource base. The nondepleting helium resources are estimted tototal 88 billion cubic feet. There is 39 billion cubic feet of helium in storage in Cliffside gasfield near Amarillo, Tex.

Jan 1, 1980

By X Yang, B Wang, L Liu

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Huoqiu iron ore field in north-west Anhui province is located in the south-east margin of the North China Craton and hosts large iron resources. Orebodies are hosted in Neoarchean amphibolite facies metamorphic rocks, forming silicon-iron bands from north to south. The area is dominated by an Early Precambrian basement consisting of Neoarchean grey gneisses, amphibolites and metasediments. The gneisses are similar with assemblages of Trondhjemite-Tonalite-Granodiorite in compositions and intercalated with amphibolites. Igneous zircons from gneisses and amphibolites have U-Pb ages of 2.86 and 2.75 Ga respectively, which are interpreted as the crystallisation ages of their protolith. Zircons from amphibolite and gneiss have eHf(t) values of 2.4–15.5 and -3.0–1.5 respectively. The tDM2(Hf) model ages of the gneiss range from 2.87 to 3.14 Ga, which is consistent with tDM1(Hf) ages of amphibolite (2.84–3.16 Ga). The U-Pb-Hf isotopes thus confirm that the gneisses were generated by partial melting of amphibolite. Two granites produce two group Hf isotopic compositions. The older one (1916 ± 42 Ma) has eHf(t) values and tDM1(Hf) ages of -9.4–3.4 and 2.24–2.71 Ga respectively, whereas the younger one (1823 ± 41 Ma) shows a large variation in eHf(t) values of -18.1–12.5 and tDM1(Hf) model ages of 1.73–2.92 Ga. Geological and geochemical characteristics indicate that the Huoqiu banded iron formations are a Superior-type iron formation rather than an Algoma-type as previously considered.CITATION:Yang, X, Liu, L and Wang, B, 2015. Study on the Huoqiu banded iron formation, West Anhui Province, East China , in Proceedings PACRIM 2015 Congress, pp 649–656 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Natalya. N. Ankusheva

The problems of ore-bearing palaevolcanic structures in folded belts are actual because of their high productivity in nonferrous, ferrous and noble metals ores. Now relationships of location and conditions of formation for sulfide-massive and gold-bearing deposits are investigated very well in Urals. But carboniferous sulfide-barite mineralization, for example the barite veins in Arcaimsky palaevolcano are?nt studied enough now [3-5]. The purpose of this research is the studying of mineralogy and thermobarogeochemistry of barite from the hydrothermal veins. It will allow to determine the conditions of its formation and to compare it to the similar mineralization of others ore types.

Jan 1, 2006

By Michael M. Hamilton

U.S. Bureau of Mines personnel examined mines, prospects, and mineralized areas to determine mineral resources and resource potential in and adjacent to the North fork Smith RARE II study area. Most mineral resources identified in this area are in laterites, highly-weathered residual soil zones. In the RARE II area, resources of nickel, cobalt, chromium, and magnesium were identified at 15 laterite properties and chromium resources at one chromite mine. Other commodities include copper, gold, silver, and mercury (fig. 1). Approximately 1,100 lode and 1,200 placer claims have been located in or adjacent to the area. Most placer claims are for literites. There are no patented claims or mineral leases. Forty laterite deposits on 15 ,properties within the RARE II area (fig. 2) contain about 16 million tons of identified marginal reserves and subeconomic resources containing nickel, cobalt, chromium, an magnesium (table 1). Most deposits have keen explored and are currently claimed. California Nickel Corporation is developing laterites on Gasguet Mountain, within and adjacent to the southeastern and western parts of the study area. If this project proceeds to production, a laterite processing plant on Gasquet Mountain would enhance the minability of other deposits in the study area. The Climax, PFM, DF, and Stone Corral properties (fig. 1, nos. 1, 6, 9, and 23) have deposits of sufficient tonnage and grade to attract mining interest; resources at these properties are in and adjacent to the RARE II area.

Jan 1, 1983

By Frank B. Fulkerson

Aluminum production in the Pacific Northwest has a new potential for expansion and increased stability of operation. This new potential results from greater availability of power; lower freight rates on alumina and aluminum; good market prospects for the metal, including western aluminum market expansion following a decline in defense requirements in the 1950's; and possibility of developing bauxite deposits in the Pacific Basin as well as other mineral resources. INTRODUCTION This is a report of a special study by the Bureau of Mines of the primary aluminum industry of the Pacific Northwest. It outlines developments relative to the United States as a whole.

Jan 1, 1962

By J. Lovering, M. Allan

"INTRODUCTIONThe Afton Mines property is located 180 air miles east-northeast of Vancouver and nine miles west of Kamloops, a city of 60,000 people in south central British Columbia. The deposit is located adjacent to the Trans-Canada Highway at an elevation of 2,231 feet above sea level.Interest in the property dates back to 1898, when a 330 foot shaft was sunk on the Pothook claim immediately south of the existing operations. Since that time many companies and individuals have investigated the possibilities of the area but it was not until 1972 that Afton Mines Ltd. located a significant zone of copper mineralization. The feasibility study was completed in the period 1974-1975, by Teck Corporation Ltd., who control Afton through 50% direct ownership and 65% ownership of Isa Mines, who own a further 23%. Construction began in March, 1976. Ore production started in August, 1977, and the first ore was fed to the mill on December 8. This was the third mine to be brought into operation by Teck since 1975, the others being Newfoundland Zinc and Niobec.The orebody is a porphyry copper deposit which has undergone supergene alteration. It is 1,700 feet long in a west-northwest by east-southeast direction, 300 feet wide and dips at 55° to the south. The mineralization in the supergene zone, which accounts for two-thirds of the known deposit, is rather unusual in that the copper is present primarily as native copper and chalcocite. The grade is one percent with the distribution: 70% native, 25% chalcocite, and 5% chalcopyrite with bornite, covellite, and cuprite."

Jan 1, 1979

By J. P. McGee

The Bureau of Mines is doing research and development work on a coal-fired gas turbine plant initially developed by the Locomotive Development Committee, (LDC) of Bituminous Coal Research, Inc. The Bureau is redesigning the turbine blading and some of the auxiliary equipment, and is reerecting, the plant at the Morgantown (W. Va.) Coal Research Center. The present goal is a 1,500-hour run at virtually the same operating conditions used by the LDC in their final 1,100-hour test with the turbine. This will allow the Bureau to properly evaluate the new blade design. Erosion of the turbine blades (particularly the roots) by ash in the hot gases from the combustion of coal was the most serious problem in extended operation in earlier experimental work. New blades made of Stellite6 are being fabricated for the stator and rotor, and armored wear strips of titanium carbide will be inserted in the blades at the areas of probable maximum ash velocity and concentration. The trailing edges of the rotor and stator blades are being thickened and thinned, respectively, to induce the ash to travel to the casing and prevent it from returning to the base of the rotor blades. The first stage rotor and second stage stator blades are being removed to provide an annular space for maximum quantities of coal ash to centrifuge to the casing. Additional blades will be added to most of the rows in the stator to stop secondary flow of dust-laden gas toward the rotor. A contract has been awarded for fabrication of the new blades. The 1,500-hour run will be started as soon as the new blades are installed.

Jan 1, 1962

Coal has been mined in the central Appalachian coalfields of southern West Virginia, western Virginia, and eastern Kentucky for more than a century. The dwindling reserve base consists in large part of coal that would have been considered unmineable by earlier generations. Nearly every current operation is working on a property where coal has been extracted in the past, from seams either above, below, or both. NIOSH is conducting research aimed at helping mine planners prevent hazardous conditions due to multiple seam interactions. To-date, more than 300 case histories have been collected from underground mines, mainly from central Appalachia. This paper focuses on several of the more challenging situations that have been encountered, including: • Room-and-pillar development 20 ft (6 m) beneath full extraction workings at a depth of 1,000 ft (300m) of cover (Virginia) • Pillar recovery 45 ft above full extraction workings at 900 ft (270 m) of cover (Virginia) • Near-simultaneous room-and-pillar mining with pillar recovery with 40 ft (12 m) of interburden and 1,500-2,000 ft (450-600 m) of cover (Kentucky) • Longwall mining directly beneath main entries in overlying seams (West Virginia) • Some of these operations have been highly successful in overcoming the challenges, others less so. The lessons learned from their experience will help ensure that these and similar difficult reserves can be mined safely.

By G. A. Kordosky

The concept of selectively extracting copper from a low-grade dump leach solution followed by stripping the copper into an acid solution from which electrowon copper cathodes could be produced occurred to the Minerals Group of General Mills in the early 1960s.This simple, elegant idea has resulted in a technology by which about 2.2 million tonnes of high quality copper cathode was produced in year 2000. The growth of this technology is traced overtime with a discussion of the key plants, the key people and the important advances in leaching, plant design, reagents and electrowinning that have contributed to the growth of this technology. Some thoughts on potential further advances in the technology are also given.

Jan 1, 2002

By P. I. Page

In mineral exploration the place that yields the first significant result is marked and two questions are posed immediately. Where should the next sample be drawn and how big should it be? At present the answers are arbitrary and ad hoc. They depend on personal experience and sentiment?that is hunch. The thought processes involved in reaching the decisions are unsatisfactory and unsatisfying for professionals. This paper proposes guidance on choosing sample spacing and sample size. The guidance is obtained from the grades of the samples. The grades also imply the extent of influence of each sample assay. Thus sampling and assay are integrated. The integration is achieved by changing the unit of value in which assays and grades are expressed and by exposing meanings and functions of grade beyond that of measuring rock value. The proposals are extended to guide comminution of particle size in sample size reduction and to deal with the problem of erratic high assays. Also, elucidation becomes possible of the computation of a reliable figure for average grade as a statistical weighted mean.

Jan 1, 2005

By R. Gallinger

In 1997, a group of Canadian mining companies met to review the Mine Environment Neutral Drainage (MEND) program and to consider future activities. They concluded that (1) that Canadian industry and Natural Resources Canada (NRCan) should fund a small secretariat in Ottawa to support technology transfer in Canada and, (2) that it was important for industry to continue the momentum of MEND on an international scale. The need for the International Network for Acid Prevention (INAP) was strongly endorsed by consultants, company, university, and government experts from Australia, Canada, and the United States who convened in Vancouver in February 1998. The initial focus was the development of a solid knowledge base covering the collective experience of INAP?s members to promote the dissemination of successful practices, the identification of knowledge gaps, and the formulation of effective research proposals. The sharing of information on past successes and failures alone was viewed as sufficient justification for the formation of INAP. INAP was officially launched in October 1998, and is now an effective, industry-based initiative to globally coordinate research and development in the management of sulphide mine waste. Significant improvements in the management of sulphidic mine materials through knowledge sharing, research, and development of technology by INAP will reduce liability associated with acid drainage. This paper will explore the international efforts and activities of INAP

May 1, 2005

By R. J. Visintainer, W. L. Whitlock

"Difficulties with the sizing and operation of centrifugal froth pumps are common and the underlying fluid dynamics are complex. Design and selection often relies on previous experience, offering unreliable guidance for novel applications or unexpected problems. The current paper describes a program of extensive laboratory testing on froth handling centrifugal pumps, covering a range of flows, heads, speeds, viscosity, air content and froth stability. Variations in impeller vane design and the effectiveness of an airlock venting apparatus were also examined. The program resulted in a better understanding of centrifugal froth pump dynamics and insight for the troubleshooting of field applications.INTRODUCTION The Challenge of Pumping Froth In pumping mineral processing froth, the handling of large quantities of air within the fluid is often unavoidable. Efforts to reduce the amount of air present at the pump suction, while always recommended for improving pump performance, may have limitations. Some strategies may also carry an economic penalty, such as unwanted process dilution (e.g. due to water spray or injection), or increased capital cost of equipment due to oversized pumps, sumps and/or piping. Froth pumping losses fall into several categories, as described below and represented graphically in Figure 1. • Density effects: Entrained air reduces the pressure created by the centrifugal pump in direct proportion to the reduction in bulk density. This is not a true “loss”, since the head produced by the pump (in meters of froth), may remain unaffected. However, the reduction in pressure often leads to a corresponding increase in pump speed required to drive the system, which itself leads to increased NPSH required by the pump (NPSHR). Furthermore, by adding a gas phase, the overall volumetric flowrate is increased, assuming a fixed quantity of de-aerated liquid being handled. This leads to increased suction velocity which further reduces the NPSH margin by simultaneously increasing pump NPSHR and decreasing system NPSH available at the pump suction (NPSHA). • Viscosity effects: Increased viscosity introduces an additional factor in some froth pumping applications, such as oil sands bitumen froth. Losses result from increased shear stress within the fluid flow, which increase with flowrate. Viscosity also facilitates the formation of airlock by reducing turbulence and allowing individual bubbles to coalesce more easily within the flow stream. Finally, it increases pump NPSHR by increasing local pressure drop in the vicinity of the vane inlet edges. • Airlock effects: Also known as air binding, it occurs when air or gas coalesces within the pump suction or impeller passages and begins to collect there, held by buoyancy forces within the rotating flow field. In essence, the liquid “floats upwards” towards the pump suction against the outward directed centrifugal forces. The airlock acts as a blockage, with corresponding reductions in flow, head and efficiency. NPSHR also increases, due to increased velocity and distorted streamlines in the flow circumventing the blockage."

Jan 1, 2012

The Bureau has published much data on sulfur (4, 15, 23)3, most of it dealing with national or international aspects of the sulfur industry. Little information, however, is available on sulfur marketing in specific States or areas, Therefore, the Bureau has conducted a survey of the resources, production, consumption, and economic future of the sulfur and sulfuric acid industry in States of the Central and Southern Rocky Mountain area - Wyoming, Colorado, Utah, Arizona, and New Mexico - and in the Northern Plains States - North Dakota, South Dakota, and Nebraska, even though these States do not represent an economic or marketing unit. The purpose of this survey is to review the demand for sulfur and primary sulfur compounds that draws upon the natural resources of the region, to discover opportunities for better use of these resources, and also to analyze and evaluate the patterns of consumption, sources of supply, and other factors that affect the demand for these mineral products. While this survey stresses the economic and marketing phases of the industry, a complementary report (32) emphasizes the resources of sulfur in Wyoming, Colorado, Utah, New Mexico, and Arizona.

Jan 1, 1962

By L Olivier, R J. Lowther, J L. Lett, I Brunton

Hydraulic fracturing to precondition the orebody to enhance rock mass cavability is gaining acceptance in underground cave mining applications. Assisting cavability is becoming important as an increasing number of cave mines are being implemented in hard, deep and competent rock masses where clamping stresses are higher and cave column heights may be in excess of 1000 m. Propagating large caves to surface in such conditions can be challenging as risks such as slowed propagation and air gaps can develop during the process.Underground-based hydraulic fracturing is routinely used at Cadia East as a means of preconditioning the orebody to assist in cave propagation, fragmentation and seismicity reduction. This paper presents a summary of a surface-based hydraulic fracture program that was successfully implemented to assist in the propagation of the Cadia East Panel Cave 1 (CE-PC1) cave to surface through competent overlying rock masses. In this case study, the propagation of the CE-PC1 cave slowed as the cave grew past 750 m in height, initiating a Trigger Action Response Plan regarding the cave propagation rate. Surface-based hydraulic fracturing was subsequently used to stimulate the cave to propagate through the final 450 m to surface. The paper details the equipment, strategy, implementation and risk management involved in the program as well as the key learnings.CITATION:Lowther, R J, Olivier, L, Lett, J L and Brunton, I, 2016. Implementation of a surface-based hydraulic fracturing program to successfully propagate a large cave through hard, competent near-surface rock masses to achieve breakthrough, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 83–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016