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By Henry E. Hilliard

The production, use, and emission of vanadium in the United States has been traced for the year 1991. Consumption was 3,300 tons2, exports 1,285 tons, and imports 2,013 tons. About 98% of production was used in metallurgy; the remainder was consumed in chemicals, including catalysts. Total emissions to the environment in 1991 were estimated at about 3,100 tons, including emissions due to the combustion of coal and petroleum products. Emissions resulting from the production of ferrovanadium were 130 tons, and emissions from the production of steel about 6 tons. Dissipative losses, defined as losses that occurred during use or as a result of wear, were estimated to be no more than 3 tons. Disposal losses were estimated to be about 4,600 tons. Most of these losses were steel products that contained 0.1% or less vanadium and mayor may not have been recycled. When these products are recycled by the steel industry, vanadium ends up in the steelmaking slag and does not return to vanadium use cycle. Worldwide emissions due to anthropogenic and natural sources were briefly reviewed. It was concluded that industrial emissions were about three times greater than emissions from natural sources.

Jan 1, 1994

By John L. Nieber

This information circular describes a computer program called VARSAT2D, a comprehensive unsaturated fluid flow simulator developed by the U.S. Bureau of Mines. VARSAT2D solves for either a vertical or horizontal, transient or steady-state solution in variably saturated, heterogeneous, anisotropic porous media using the Galerkin finite-element approach. Simplex triangular elements are used. Moisture retention characteristics are described by specifying either the Brooks and Corey, Brutsaert, or Van Genuchten power functions, with hysteresis described using the Maulem independent domain model. Boundary conditions may include any combination of time-varying seepage, pressure along solution domain, boundaries and/or at internal node points, unit hydraulic gradient at the lower boundary, and a uniform source and/or sink. This program should be a welcome addition for mining and environmental hydrologists, researchers, and engineers interested in modeling unsaturated fluid flow.

Jan 1, 1994

By R. D. Westervelt

IN JULY 1954, the first iron ore from the deposits in the Knob Lake vicinity was mined and shipped to Seven Islands. The beginning of the production may well be the greatest advance in Canadian economy in the past fifty years. In 1955, the Canadian iron ore output was more than twice that of 1954, an in-crease due principally to the iron ore shipments from the Knob Lake area. Previous to this, Canada's iron production was 1.85 per cent of the world's output. Now, this percentage has risen to approximately 5.5 per cent and shows every indication of increasing further as the production rate from the area is increased. In 1955 the Iron Ore Company of Canada shipped over 7 million tons of iron ore and expects to ship over 10 million tons in 1956. Present facilities may be enlarged to handle up to 20 million tons per year. If the expected I 0 million tons per year are exported, Canada's iron exports will be second only to her wheat and newsprint exports. Before production began from the Knob Lake deposits, years of development were necessary in the area. Geologists spent several summers mapping the general area in order to unravel the complicated stratigraphy and petrology. Particular attention was paid to the mapping of the iron formation and all stages of alteration from fresh iron formation to ore were observed.

Jan 1, 1957

By Dolf W. Fieldman

Most recently the geologic setting of the mineral deposits in the Silver Cliff district is described by William M. Sharp in ?Geologic Map of the Silver Cliff and Rosita Volcanic Centers, Custer County, Colorado?, (U. S. G. S. Map I- 1081). The discussion will relate only to the southern half of the Silver Cliff volcanic center and differences in geologic interpretation, which are largely structural, will be pointed out as they arise. Only the manganese/silver zone of the Kate Area will be discussed in detail.

Jan 1, 1980

By Paul L. Broughton

"IntroductionThe coal deposits, all of lignite rank, of economic interest in Saskatchewan are associated with the Ravenscrag Formation (Paleocene). Several Cretaceous formations have less significant lignite accumulations (Broughton, Irvine and W'hitaker, 1974). The Swan River Group (lower Cretaceous) and Judith River Formation (upper Cretaceous) have the only coalbearing strata in the shallow subsurface of central Saskatchewan. The Swan River Group coalfield is relatively small and underlies only 15 sq km of the surface approximately 40 km south of La Ronge, Saskatchewan. An estimated 36 billion short tons are within 45 m of the surface. No reserve estimates are known to have been calculated for the coal-bearing Judith River Formation exposed at the surface in the vicinity of the South Saskatchewan River valley in west-central Saskatchewan. Although no coalfields have been delineated, lignite beds up to 1.8 m thick have been intersected in test holes. The coal-bearing upper Cretaceous and lower Tertiary strata of the northern Williston Basin extends the full width of southern Saskatchewan for 650 km, and from the United States border 120 km north to 50° latitude (Fig. 1). Only the coalfields of the Ravenscrag Formation, because of their economic interest, will be considered further. There are four major coalfields. They are, from east to west: Estevan, Willow Bunch, Wood Mountain and Shaunavon (Cypress) coalfields. Cumulative lignite seam thickness for each basin is 10 -15 m (Figs. 2 and 3). The origin of each coal basin, resource calculations, seam stratigraphy, and mining activity are discussed. Regional Setting The Williston Basin is an ellipsoidal depression in the Precambrian basement, centered in western North Dakota and marginal to the exposed craton of northern Saskatchewan and central Manitoba (Fig. 1). The sediments of the basin range from Cambrian to Pleistocene in age and have a maximum known thickness of 4614 min western North Dakota. A maximum of 3200 m is recorded in southern Saskatchewan. Most structural deformation is late Cretaceous to early Tertiary (Paleocene) in age, coinciding with the Laramide Orogeny. The pre-Laramide Williston Basin, with a depocenter near Williston, North Dakota, began developing during the middle Ordovician, or possibly earlier."

Jan 1, 1985

By R. S. Dean

The possibility of cheap electric power for a number of mining areas in this country has suggested to many the idea of electric smelting of nonferrous ores in small units at or near the mines. The electric smelting of nonferrous ores was tested fairly thoroughly 20 years ago by United States Bureau of Mines and by others, and the fact that it did not achieve continuing workable success in any instance is sufficient proof that it offered no advantages at that time.

Jan 1, 1937

By Thomas H. Heine

"The Rabbit Lake uranium deposit is located at 58° 11’00”N.. 103°42'36""W., close to the west side of Wollaston Lake, and approximately 800 km north of Saskatoon. The orebody is hosted by Aphebian Wollaston Group rocks, initially deposited as a series of shallow-water marine sediments consisting, in part, of carbonates and possible saliferous petites. Metamorphism during the Hudsonian Orogeny, peaking at about 1850 Ma, recrystallized the sediments to upper amphibolite grade paragneisses. This was accompanied by partial anatexis. The waning stages of Hudsonian orogenesis appear to be marked by minor granitic intrusive activity.The post-Hudsonian period was marked by a long interval of physical and chemical erosion, resulting in the unroofing of the Wollaston metamorphic complex. The entire region underwent extensive lateritic weathering under tropical to subtropical conditions. Carbonates were especially vulnerable and, in the Rabbit Lake area, suffered extensive solutioning with accompanying formation of collapse breccias. Old zones of weakness also underwent periodic reactivation.It was during this period that uranium was leached from the surrounding meta-sediments by oxidizing meteoric waters, and transported into the karsted and fractured rocks of the Rabbit Lake doline.Athabasca Group sediments eventually covered the deposit, their diagenesis taking place at about 200 °C and 900 bars. This allowed the partial to complete recrystallization of the initial mineralization, resulting in a minimum age of 1281 ± 11 Major ""first""-generation pitchblende. Periodic fault/fracture reactivation modified the hydrologic regime within the deposit, resulting in episodic mobilization and recrystallization of pitchblende and other uraniferous species. This is clearly shown in the open pit at the present time: uranium is being mobilized and recrystallized on damp pit walls as bayleyite and liebigite due to the modification of the hydrologic system by mining activities.The uranium mineralization occurs mainly as fracture fillings, coatings, and impregnations within breccia zones and intensely altered metasediments. Lesser mineralization is intimately associated with phyllosilicates which form the matrix of a carbonate-col/apse mega-breccia. The primary ore mineral is pitchblende, consisting of five generations, and from which a large suite of secondary uraniferous minerals have formed. On a gross scale the metal content of this deposit appears to be simple, consisting almost exclusively of U, but minor Ni, As, Cu, Se, Fe and Co are also present. The eastern limit of the mineralization is defined by a vertically-dipping microgranite dyke - breccia complex, containing high-grade uranium values. The orebody is truncated to the west and at depth by the Rabbit Lake reverse fault. Minor mineralization occurs as fracture fillings in unaltered plagioclasite in the footwall of the ore body. Precipitation of uranium from solution could have taken place by a number of processes. A mobile reductant (methane, carbon dioxide, etc.) may have been generated from graphite present in some of the host rocks of the orebody. Sulphides are also a common accessory and may have aided in the formation of a reducing environment. Phyllosilicates may have acted as adsorbants for uranium, allowing for its fixation. This metal has also been incorporated into the phyllosilicates themselves."

Jan 1, 1986

By K. Adham, C. Lee

The demand for nickel is continuing to exceed inventories, and producers are working vigorously to increase capacity. Many nickel processes utilize the fluidized bed technology for its fast heat and mass transfer, excellent temperature control and low maintenance. The following four nickel applications of the fluidized bed technology have been commercialized: I) Sulfide ore roasting; II) Nickel sulfide (matte) roasting; III) Nickel oxide reduction; IV) Nickel chloride pyrohydrolysis. This paper examines the issues surrounding the application of fluidization technology to the above processes, from the stand point of the engineer modeling the process and designing the key equipment, based on the historical success stories and the fundamental principles of flow sheet synthesis. Using the available data in open literature, typical flow diagrams (with convenient bases of 1 t/h feed or product) are developed to illustrate the relative flow rates and to highlight the key features of each application. In addition, some historical background information is provided for each process with supplemental notes with regards to our company's involvements.

Jan 1, 2005

By D. E. Cameron

The Cannon mine, located in north-central Washington is mining gold hosted in silicified Eocene-age arkosic sediments arrayed along a regional strike-slip fault system. Branches of the Eagle Creek fault have broken the Chumstick Formation into blocks and wedges, and have caused intense deformation of stratigraphy in the mine. Mineralization at the Cannon mine (B-Reef) and O-Reef (L-O mine) is a bulk silicification with high grade cross-cutting veins containing principally electrum, silver sulfosalts and pyrite in a gangue of quartz, adularia and calcite. Orebodies have very irregular shapes, but tend to follow stratigraphy and high-angle pre-mineral fault breccias and splays developed adjacent to the major faults. Both B-Reef and O-Reef occur at significant bends in the regional trend of major fault strands. Mean gold grades decrease upward from near sea level to the 300 m elevation at the Cannon mine. A new discovery, the A-Reef is hosted by a moderately dipping structure which is at a low angle to bedding. Fluid inclusion studies of B-Reef ore zones indicate dilute ore-bearing fluids boiled at temperatures between 185 and 2850 C at a depth of 1 km. Many ore zones are bounded by sheared mudstone and claystone and a much broader halo of argillic alteration comprising illite, smectite and sericite. Trace and major element analysis by ICP-ES for 33 elements, LECO for S, Hg by CVAA and gold by AA-FA shows dispersion patterns hundreds of meters outward from the known orebodies in the Cannon mine. Geometric mean comparisons, hierarchical R-mode cluster analysis and single element spatial plots show that Hg, As, Sb, S and K/Al compose a suite of elements which are significantly dispersed away from, and increase toward mineralization. Ba, Ca, Na, Mn, V and Zr decrease toward mineralization. The suite is more selective than gold with respect to known mineralization within the exploration area.

Jan 1, 1992

By Lowell L. Patten

The Federal Bureau of Mines participated with the National Aeronautics and Space Administration and Martin Marietta Aerospace in developing, building, and testing a portable X-ray fluorescence spectrometer for use as an analyzer in mineral-resource investigative work. The prototype battery-powered spectrometer, measuring I1 by 12 by 5 inches and weighing only about 15 pounds, was designed specifically for field use. The spectrometer has two gas-proportional counters and two radioactive sources, 109Cd and 55Fe. Preliminary field and laboratory tests on rock specimens and rock pulps have demonstrated the capability of the spectrometer to detect 33 elements, to date. Characteristics of the system present some limitations, however, and further improvements are recommended.

Jan 1, 1982

By D. Randolph Berry

The U.S. Bureau of Mines awarded a contract to Foster-Miller Associates, Inc. (FMA) to provide recommendations on the safest, most practical methods for complying with new regulations requiring that all underground coal miners have a self-contained, self-rescuer (SCSR) -a device capable of supplying, in an emergency, 1 hr of self-contained oxygen (no breathing of mine air). This report develops information and recommendations which could be used during the early stages of nationwide compliance, especially in the areas of inspection, testing, and underground storage of SCSRs. Volume I contains an Executive Summary, Introduction, Definitions, Recommended Guidelines for District Managers and Mine Operators, and a Storage Plan Checklist and Sample Form.

Jan 1, 1981

By A. Brown

THIS P APER has been pre-pared as a progress report on Mines Branch investigations into problems of ground stress in certain co al mines of Western Canada. As such, it should be considered as a companion report to the one ( 1) presented to the Mining Society of Nova Scotia in 1956 and which dealt with similar investigations in the coal mines of Eastern Canada. For the past 50 years, dynamic incidents in the form of 'bumps' and 'outbursts' have been occurring in the coal mines of the Inner Foot-hills belt of tl1e Canadian Cordillera. As these phenomena generally become more frequent with in-creased thickness of overburden, a limiting depth of mining of 2,500 feet has been set (2) for estimating recoverable reserves of coal. If such a view were accepted, from a long-term viewpoint very large resources of coking-grade ?coal -in a part of the continent deficient in such coals -would not be available to the nation. The terrain in which these in-6dents take place may be described in geological terms as being dominated by pronounced structure in strata ?consisting of a large proportion of highly indurated rocks. The Geological Survey of Canada has co-operated by carrying out structural studies (3) at the mines, supplemented lithological by stratigraphic observations.

Jan 1, 1958

By Richard L. Unger

The Bureau of Mines entered into a cooperative agreement with an eastern Kentucky coal mining company to comprehensively redesign the flow of equipment and supplies throughout its underground mines. Items were tracked from delivery to the warehouse and from surface storage areas to their final usage locations underground. Three underground mines were visited, and a great variety of tasks were videotaped for subsequent laboratory analysis. Of particular interest were tasks that required manual handling of the supplies or equipment components. Activities such as handling daily supplies (concrete blocks, rock dust, and cross- beams) and handling or lifting the continuous miner power cable were determined to be the most hazardous. Recommendations to the company included redesigned surface storage areas to facilitate the use of forklift vehicles to load the underground supply cars. Designs were also developed for different mechanical- assist devices to help in unloading the supply cars underground and to handle equipment maintenance tasks underground. Additionally, the videotapes of the underground manual handling tasks became the basis for simulating those activities in controlled laboratory conditions. This testing will contribute to developing guidelines for proper lifting techniques for low-seam coal mines.

Jan 1, 1986

Classification within the Inferred Resource category is based on geological judgement and the balance of extrapolation versus interpolation that the Competent Person is prepared to accept. These resources are typically drilled at spacings well in excess of the geostatistical range and at a density that is non-uniform. In many cases, a substantial proportion of the available data will be historical, and should be considered with more recent data sources. The provision of a robust geological model will increase the confidence in any resource estimate, and should be viewed as a critical component. The definition of Inferred Resources is of great importance to vein gold projects, since Indicated and Measured Resources generally require costly underground development for delineation. Indeed, many gold vein operations possess substantial quantities of Inferred Resources (>75 per cent) in their resource inventory both at project start-up and during production. This contribution explores a number of the key issues when using the Inferred Resource category and presents four recent case studies.

Jan 1, 2006

By Corby G. Anderson

In the majority of industrial operations recovering gold and silver by hydrometallurgical means, cyanide is the predominant lixiviant. However, as an economic alternative, production of massive quantifies of silver chloride was done on an industrial scale in the nitrous-sulfuric acid pressure leaching of a refractory precious metals concentrate. This proven process required no cyanide. Thus, because of the large volumes encountered during day-to-day plant operation, the need for efficient and low cost methods of silver chloride precipitation, reduction and materials handling was mandatory. As such, this paper covers the evolution of plant scale precipitation, filtration, washing, reduction and control of silver chloride processing. As well, an in-depth description of the unique leaching system is included.

Jan 1, 1998

By Roy J. M. van Lier

In industrial aqueous solutions, germanium generally occurs in trace amounts amid high concentrations of other metals, such as zinc, copper and iron. Separation of germanium from these metals as well as its isolation from gallium and indium pose a real challenge to the hydrometallurgist. After a brief discussion of the aqueous chemistry of germanium, this paper reviews the flowsheet of the Apex Mine in Utah. The Apex property was the only mine in the world to be operated primarily for production of gallium and germanium, but apparently closed due to great operating difficulties. Several process variants proposed for the treatment of the Apex ore, including bioleaching methods, are addressed. Following a more general description of the behavior of germanium in hydrometallurgical zinc processing streams, available technology for its recovery from aqueous solutions is summarized. Precipitation, solvent extraction, ion exchange, electrowinning, ion flotation and liquid-membrane separation are all outlined in terms of the aqueous chemistry of germanium. Finally, the production of high purity germanium dioxide and metal is briefly discussed

Jan 1, 1995

By F. E. Block

The reaction between calcined dolomite and ferrosilicon has been studies with the aim of developing a continuous process for magnesium production. Small-scale tests were made in vacuum retorts similar to those used in the vacuum retort process as developed by Pidgeon (1)2/ and operated during the period of World War II in several Government-owned plants. Factors investigated with respect to the silicon efficiency were the reaction temperature, reaction time, amount of excess dolomite in the charge, and effect of adding sodium silicate to the charge to serve as a binder. Additional laboratory tests were made to study the reaction at elevated temperature but at atmospheric pressure. Silicon efficiencies exceeding 80 percent were found to result when operating in the temperature range from 1,750° to 1,800° C. for periods of 20 to 30 minutes.

Jan 1, 1956

By J. E. Tiffany

A stick of explosive is a package of stored energy that can be released when needed to blast rocks, coal, and other materials; but, unlike fuels such as coal and gasoline, its potential energy is self-contained, there being enough oxygen within the package to complete the almost instantaneous reaction. When an explosive is ignited or detonated, the solid or liquid materials of which it is composed are converted rapidly into highly heated gases, which, if free to expand, would have a volume many times larger than that of the original explosive. At the instant of explosion these gases occupy only the volume of the shot hole and are therefore produced at a very high pressure, which causes the material that is being blasted to be broken or disrupted. In blasting coal efficiently the proper placement of the shot hole and the confinement of the explosive therein are both of prime importance. When these are not adjusted properly, only a small amount of the energy is expended in bringing down coal, consequently the balance of the energy tends to be expended by the emission of a flame into the working place that may lead to a gas or dust explosion. Permissible Explosives Defined The term "permissible explosive", as applied by the Bureau of Mines to explosives it has approved for use in blasting in coal mines, embraces not only the requirement that the explosive, when used, shall be similar in all respects to the basic sample that passed all the tests necessary for its admission to the published permissible list, but also that the explosive shall be used under certain prescribed requirements.

Jan 1, 1938

By R. W. Dougherty

From time to time interest has been evidenced in transporting coal with water in pipe lines. About the year 1895, United States patents broadly covering a method of pumping coal with water through pipelines were granted to W. C. Andrews. His process was used to some extent in pumping anthracite culm and waste back into the worked-out portions of the mines. About 1905, W. T. Donnely was granted patents relating to pumping anthracite silt away from the breakers. From about 1913 until 1924, a British engineer, Gilbert G. Bell, used a short pipeline to convey coal with water from barges on the Thames River to the Hammersmith Electricity Generating Station, London. Minus 5-inch coal was transferred 660 yards through an 8-inch pipe. Some trouble was experienced with fine coal, which tended to plug the line. Bell made several proposals to transport coal by pipeline overland from the Midlands to London, a distance of about 100 miles, but these were never adopted. This survey is concerned mainly with the problems presented by actual pipeline transportation of coal with water. It is assumed that the coal will have been processed to remove most of the abrasive impurities by conventional methods prior to introduction into the line, and that it has been crushed to the required top size. Dewatering at the discharge end of the line is considered part of the conventional cleaning process. There still remain many pump-performance and behavior of water-coal mixture problems that can be solved only by actual performance tests. It is recognized that the distribution of coal to other than very large users is not changed. Large storage areas would be required to supply seasonal markets. Large users, such as power plants and heavy industries, could be supplied by branch lines directly to the point of use, It is also recognized that pipe lines might not be able to carry a full range of sized coal to meet market demands in many areas.

Jan 1, 1951

By J M. Santini, I C. A Streimann

Arsenic is a naturally occurring element in the environment and is toxic to biological systems. Arsenic can exist in the environment in the following redox states, arsenite (+3), arsenate (+5), arsine (-3) and elemental (0) (Oremland and Stolz, 2003). Arsenic is released into the environment by natural and anthropogenic activities such as rock weathering and ore mining, respectively. Such activities result in the release of the soluble inorganic arsenic oxyanions, arsenite and arsenate. The redox state of arsenic in the environment is influenced by a number of factors including, redox potential, pH and microorganisms (Irgolic et al, 1977; Genc-Fuhrman, Tjell and McConchie, 2004). Recently, the ability of microorganisms to influence the cycling of arsenic in the environment has attracted much attention. Microorganisms that can oxidise arsenite and reduce arsenate have been isolated and the mechanisms of arsenic metabolism are currently being investigated. The differences between arsenic resistance and arsenic metabolism are being revealed. The role of microorganisms in the release of arsenic into the environment is of particular importance with arsenic contamination of waters causing the death of millions of people worldwide, due to the consumption of contaminated water (Vasken Aposhian et al, 2003; Islam et al, 2004).

Jan 1, 2004