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The Bureau of Mines Minerals Information organization collects worldwide data on virtually every commercially important nonfuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. This data collection activity was instituted by the 47th Congress in an appropriations act of August 7. 1882 (22 Stat. 329), to place the collection of mineral statistics on an annual basis. The most recent authority for the Bureau of Mines Minerals Information activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress), which strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1985

The Bureau of Mines Minerals Information organization collects worldwide data on virtually every commercially important nonfuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. This data collection activity was instituted by the 47th Congress in an appropriations act of August 7. 1882 (22 Stat. 829) to place the collection of mineral statistics on an annual basis. The most recent authority for the Bureau of Mines Minerals Information activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress), which strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1987

By Yeonuk Choi, Patrick R. Taylor, Lyle Cunningham

Laboratory experiments have been performed to evaluate the potential for metal removal and recovery from river bed tailings by ferric chloride leaching. The lead, zinc, silver and other metals in the river bed occur due to the old method of dumping mill tailings into rivers. This was practiced prior to the introduction of tailings impoundments. The effects of the leaching method, leaching time, pulp density, ferric chloride concentration, and leaching temperature on the rates and recoveries of lead, zinc and silver were studied. The effects of pulp density and leaching temperature were significant on the extraction rates of lead, zinc and silver. The lead content in the leached tailing was reduced to 0.023 percent, when using an 353O K leaching temperature and 0.384 g of FeC13/1 g of sample.

Jan 1, 1992

By Petri Bryk, John Ryselin, Rolf Malmstrom, Jorma Honkasalo

THE theoretical possibilities for the realization of flash smelting have been known for a long time. Calculations concerning the same can be found in previously published literature,1 and suggestions for its accomplishment in practice are described in patents on the subject. Likewise a smaller number of practical test results are known. Autogenous smelting is closely connected with flash smelting, since in flash smelting techniques it is possible to use the heat evolved by oxidation of the sulfides for the smelting process to such an extent that under certain conditions smelting can proceed without additional fuel. However, in the event that insufficient heat is available from the oxidation of the sulfide concentrates, then additional heat may be supplied by preheating the air, using oxygen enriched air, on burning additional fuel with the concentrate.

Jan 6, 1958

By Barbara C. Williams

U.S. Bureau of Mines researchers conducted field studies at an abandoned copper-gold mine tailings impoundment. Pore water quality was analyzed in the vadose and saturated zones. Three statistical procedures were employed to summarize the variability within and between the two zones. The results indicated that linear combinations of those variables reflecting sulfide oxidation and aluminum-silicate weathering best summarized the variability in each zone, and that the zones were most different on the basis of sulfide oxidation variables. The geochemical computer code WATEQ4F was used to assess the solubility status (saturation index) of minerals. Saturation indices of sulfide oxidation and aluminum-silicate weathering minerals were different in the two zones. It was demonstrated that the statistical analyses produced similar and complementary results to the geochemical code.

Jan 1, 1992

By Y. Q. Zhang, Y. Luo, S. S. Peng

Burrier pillars in underground coal mines could eventually be subjected to a water head due to the build-up of mine water in the old workings. The water head could not only act ns a force to destabilize the pillar, but it could also cause seepage flow through the pillar and its surrounding strata. Excessive seepage flow could induce piping failure that, ill turn, could accelerate the mechanical failure process of the barrier pillars. In this paper, a finite element simulation approach was employed in the evaluation of the barrier pillars. Both the stress distribution and the seepage flow pattern in and around a barrier pillar have been simulated numerically. The effects of ground stress on rock permeability to water seepage has been taken into consideration in these simulations,

Jan 1, 2002

By D. H. Yardley

GEOCHEMICAL investigation of trace elements in surface materials was begun near Ely, Minn., in 1953 along the basal contact of Duluth gabbro with Giants Range granite (Fig. 1). This article presents data on the distribution of copper and nickel in till and in stream sediments in the area and proposes an explanation for the types of distribution found. The Duluth gabbro, one of the world's largest basic intrusives, intrudes rocks which range in age from Keewatin to middle Keweenawan. Within the test area the gabbro is in contact with granite except for short sections where it is in contact with remnants of iron formation. Sulfide mineralization occurs within the gabbro, near and parallel to the basal contact for a distance of several miles. Schwartz and Davidson1 have described the geologic setting of the mineralization.

Jan 7, 1958

This paper discusses the recently com- pleted TBM-driven pressure tunnel at the Sand Bar Hydroelectric Power Project. The Sand Bar Project is a diversion scheme situated on the middle fork of the Stanislaus River in the Western Sierra Nevada, California, U.S.A. As part of the project, a 5.6 km long and 3.71 m diameter unlined pressure tunnel was bored by a Jarva TBM at the average rate of .37.5 m/ day. This report deals with construction aspects of the tunnel, including TBM performance, lining design, and remedial support measures. Correlations between TBM performance, geologic conditions, and rock properities are made, and the Contractor's mode of operations are discussed. Advance rate prediction, and the impact of these excellent advance rates attainable in hard rock using the new machines are discussed.

Jan 1, 1987

By H. Landsberg

SUBSIDENCE caused by mining operations has been a matter of interest for the mining engineer for just 111 years, since the Belgian Committee for study of subsidence in the city of Liege submitted its first report in 1825. This interest is fairly expressed in the enormous amount of literature that has since appeared on this subject. A bibliography, probably far from being complete, which preceded this study as a pre-liminary survey, comprises more than 800 titles. In spite of this fact the problem remains today as acute as it has ever been. The questions of as good a recovery as possible of the national resources, the safety of the operations, and the protection of private and public property are the important angles from which to look at the problem.

Jan 1, 1936

By Y. Lizotte

This paper describes the design and implementation of the dispatching system at LAB Chrysotile Inc.'s Black Lake Mine Operation, Quebec, Canada. The initial system uses a computer in a passive role, to record and display information in ongoing operations. Simulation studies were undertaken at McGill University to assess various heuristic dispatching rules which can be program- med and inserted into the dispatching system. The computer can then suggest to the operator where a truck should be sent to maximize productivity or improve fleet efficiency. The study stresses the importance of considering the effects of implementing computerized systems on those individuals who must use these systems in their daily work. The roles of individuals from the industry and the university in this joint project are also highlighted.

Jan 1, 1987

By John D. Kalasky

Continuous mining has revolutionized the coal industry but intensified the problems of earlier mechanization. From the installation of the first miner, it was recognized that face ventilation would be one of these problems. To establish an efficient work cycle for the equipment being used, conventional mechanized mining provides four or more development faces. Continuous mining, relying on a single machine, requires only one face, although more than one can be driven alternately by the same machine. In gaseous areas mined by the older methods, the intermittent rate of exposure allows time for the face to bleed off or be cleared, and the width obtained with conventional units makes it possible to hang a brattice line almost to the face. Continuous mining increases the ventilation hazards; there is no margin of time, and very limited space.

Jan 9, 1959

By N. Arbiter, J. Steininger, C. C. Harris

Power consumption and operating variables in air-liquid systems for a wide range of operating conditions in the turbulent region have been correlated by two dimensionless groups involving the power ratio and the flow number. The form of the correlation was developed by considering flow balances related to the air-liquid composite density in the impeller zone. Data for two phase air-liquid systems, both from literature and from the present investigation, has been correlated with high statistical significance. Two phase solid-liquid and three phase gas-liquid-solid systems have also been correlated. The quantification of power requirements in the agitation of liquids is well established.1 Rushton, Costich and Everett have shown that, for mixers operating in the fully turbulent region with no vortex, the power number

Jan 1, 1964

By Walter E. Dean

Deep-sea manganese nodules are considered to be potential ores of manganese, nickel, cobalt, and copper. Considerable time, effort, and funds have been applied to the study of the distribution of nodules on the seafloor and the location of economically important areas, but less effort has been spent in understanding the origin of nodules. Most theories that have been proposed to explain the origin of manganese nodules have been based on inorganic processes. It is not by coincidence, however, that the area considered to be most economically feasible is, in the zone of high biological productivity in the eastern equatorial Pacific Ocean and underlain by siliceous biogenic sediment. The genesis of manganese nodules and the concentration of many trace elements are related indirectly, and possibly directly, to the activities of organisms.

Jan 1, 1983

By Toomey P. T

In many open cut coal mines, rivers and large creeks can cause planning and operating difficulties, both in the terms of the more obvious location of the current watercourse, but, and sometimes more importantly, past meandering of the watercourse. Prevent and past flow regimes may have deposited large alluvial sequences within the current mining areas. The presence of groundwater within the alluvium further complicates the planning and operating practices.A situation exists at Saraji Mine in which alluvial sediments overlie a massive sandstone sequence which in turn lies at about one metre above the coal seam. The problems encountered include high levels of groundwater ingress to the pit, highwall instability, and an unacceptably high rate of blast hole collapse (prior to charging with explosives). Other aspects of the dragline stripping operation were also affected.

Jan 1, 1992

By R. D. Deister

The Buick concentrator represents state-of-the-art technology in automated digital process control operation utilizing a centralized computer. The process control strategies implemented at Buick are no longer new to the industry, but the successful application of these developments is still rather unique in North America. Productivity improvements, determined to be a direct result of the process control developments, are the primary topics of this paper. Emphasis is placed on metallurgical benefits including both lead and zinc recoveries; lead concentrate grade; and reductions realized in reagent consumptions, operating costs, and personnel. A detailed description of the concentrator, along with a history of the process control development and a more in-depth discussion of the control strategies implemented at Buick can be found in the references. (The Buick flowsheet is depicted in Fig. 1).

Jan 1, 1987

A week-long educational program and two-day symposium on applying the fluidizing reactor to the minerals industry drew more than 100 engineers to the University of Arizona at Tucson several weeks ago. The educational program, intended for engineers who will work closely with the reactor, attracted registrants from all sections of the U. S. and Canada. Meeting at the College of Mines on February 23 for a full week of intensive classwork, the engineers ploughed in with enthusiasm. Eight hours daily of lectures and laboratory work were followed by a generous helping of homework supplied by Professor Sigmund L. Smith, who directed the course. The study program was completed on Friday and the following Monday marked the start of a symposium of technical papers covering a wide variety of operations and new ideas.

Jan 4, 1959

By R. J. Sweigard, R. V. Ramani

Three case studies were undertaken to investigate the role of land use potential evaluation in reclamation planning and to determine the impact of regional differences on final land use plans. The three surface mines studied were representative of operations in the Appalachian, Interior, and Northern Great Plains provinces. The scope of the investigations included a survey of regional characteristics, a detailed investigation of the mining operations and site conditions, and an assessment of local land use planning activities in the area of the mines. Special attention was given to key factors that presently determine the use of reclaimed land. Also, for each case study, the postmining land use potential was evaluated using site planning principles. Specifically, the environmental, economic, and social impacts of several potential postmining land use plans were considered.

Jan 1, 1987

By K. V. S. Sastry, A. J. Hunt, K. D. Lofftus

Sol-gel processing is rapidly becoming an important process for producing such advanced materials as high activity catalysts, fiber optics and ceramic precursors. These materials can be tailor made with properties unique to sol particles as well as the gel aggregates by controlling production of the sol, the formation of the gel, and the removal of the interstitial fluids. This paper presents colloidal and kinetic principles of sol generation and gel formation. Hydrolysis of alkoxides provides the best means of controlling sol production and electrostatic stabilization enables the formation of the most homogeneous gels. Gelation occurs by hierarchial aggregation which produces inhomogeneities much larger than the sol particles. Colloidal and kinetic principles can be applied to reduce the size of the inhomogeneities and obtain high performance transparent insulation and new ceramic composites.

Jan 1, 1990

By E. E. Carpenter

(San Francisco Meeting, September, 1915) BELIEVING that the results accomplished in the mill of the Churchill Milling Co., Wonder, Nev., during the fiscal year ended Sept. 30, 1914, will be of interest, I am presenting the more prominent facts and figures showing the progress made in treating this ore with especial reference to tonnage, supplies, costs, and extractions. The mill is situated at Wonder, Nev., in the Wonder mining district, 55 miles east from Fallon, Nev., the nearest railroad point. All supplies are hauled this distance by freight teams, this method of transportation having been found more reliable for continuous service than trucks, the price paid for hauling being slightly under one cent per pound. In this mill are treated the ores of the Nevada Wonder Mining Co. ,

Jan 6, 1915

By K. C. Ko, M. K. McCarter

Experimentation with seismic velocity measurements at Kennecott Copper Corp.'s Bingham mine disclosed that some recognized slide areas are characterized by low velocity profiles. A new traverse technique employed during the investigation allows rapid and precise measurements of a quantity referred to as "apparent velocity." This value is a weighted average of the actual velocity in the overbreak zone near the surface and in the intact rock at depth. The low points on the velocity profile are apparently the result of lower actual velocities and deeper overbreak in less competent material within the slide zones. Experience verifies the usefulness and practicality of the technique in delineating adverse areas prior to detectable failure. The technique may be employed as a rapid and economic means of slope stability surveillance in large open pit mines.

Jan 1, 1973