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By M. M. Fine

A process for simultaneously reducing and indurating iron are pellets was developed by Bureau of Mines laboratory research and confirmed on a continuous pilot plant basis. Moist iron are concentrate was balled, mixed with solid reductant, and heated at about 1,100° to 1,150° C. On a small scale, a variety of concentrates and fuels were utilized successfully. The pilot rotary kiln tests were limited to natural magnetite, synthetic magnetite, lignite, and anthracite. In both cases, partially reduced pellets with excellent physical properties were regularly produced with average analyses of at least 80 percent total iron and 60 percent or more metallic iron. These and other prereduced pellets were smelted in the Bureau's experimental blast furnace facility, Bruceton, Pa. With prereduced spheres comprising 85 percent of the burden, the coke rate was approximately half that with standard oxide pellets and production of hot metal was increased by 75 percent. Economic appraisal of the cost of making hot metal indicates that reduced pellets could be more profitable than any other iron raw material in both investment capital and daily cost of operation.

Jan 1, 1970

By Michael G. Mayer

Since its invention in 1859 various designs of lead batteries have evolved to meet commercial needs for traction applications and standby power. In recent years major developments have taken place in lead alloys and the chemistry and mechanical design of industrial lead batteries. These are reviewed in relation to their commercial application together with the new type of maintenance free gas re-combination lead-acid batteries which are opening so many new markets for lead.

Jan 1, 1990

By Bolmerm R. L.

This information circular describes the application of modern methods and equipment in sinking a vertical, 916-foot-deep by 16-foot-diameter, concrete-lined access shaft for the Harold D. Roberts tunnel near Montezuma, Colo. Although the access shaft was merely a construction facility to expedite completion of a 23-mile water-diversion tunnel, a circular shaft of this type would be equally adaptable for mine development or other purposes. Comparable sinking methods and equipment could be used for similar shafts within a wide range of sizes and depths. SUMMARY In addition to excavation and support of the basic access shaft to tunnel grade, the overall sinking project involved initial preparation of a surface site and plant, subsequent construction of a tunnel-level station and loading pocket at the shaft bottom, and ultimate conversion of the basic shaft into a hoisting and access facility for tunnel operations. The sinking period for the basic shaft approximated one year. Actual tunnel operations through the converted shaft began on April 3, 1958, approximately 19 months after the project was initiated.

Jan 1, 1961

By Ginger S. Evans

This report documents a preliminary hydrologic investigation of an area where longwall mining methods are to be used. The scope of work includes: determination of physical and chemical characteristics of major soil types in the area; determination of physical and chemical properties of surface water bodies; collection of geologic characteristics, including stratigraphy, structure, and detailed aquifer descriptions; collection of 10 years' meteorological data and installation of a weather station; and a detailed ground-water investigation that includes completion of observation wells, aquifer testing, water quality sampling, and analysis using a 3-D computer model. The Trescott model developed by USGS was used to simulate steady-state aquifer conditions. Input data from 8 multiple-completion monitor wells were used to model an area of approximately 10 square miles. Two layers, coal and overburden, were simulated, both confined. Model results showed good agreement with know piezometric data, desaturated areas, and flow from springs. The study area was found to have very low-yield bedrock aquifers with transmissivities ranging from 5 to 320 ft2/day for the coal (depths from 500 to 1,200 ft) and from 499 to 576 ft2/day and fractured sandstone units (depths less than 100 ft). Annual precipitation and recharge are very low, 10 to 11 inches and 0.25 inch respectively. The area has very high relief and large areas of rock outcrop. No perennial streams are present on the site.

Jan 1, 1983

By Glenville A. Collins

IN 1932, Horace Onyett at Oroville, California, built a practical floating washing plant along the general lines as now known, using a 24 in. by 12 ft. trammel; it was fed with a ½ yard dragline bucket, rated then at 200 yards per day. Onyett dubbed his plant a 'Doodlebug' which name has clung to this type of operation ever since. In general, the 'Doodlebug' dredge is the outgrowth of the depression of 1929, wherein many dirt contractors had surplus idle equipment and a few of them ventured to use it for placer mining. Many such plants were impractical and poorly designed and adapted often to locations not suited to the purpose. However out of the general idea came refinements until today dragline dredging has a very definite place in the gold production of the world. Many of the early operators, being mainly contractors without mining experience or technical knowledge of gold saving, geology, or mechanical design, naturally went through stages of trial and error until a workable unit became standard practice. Credit should be given Bodenson Iron Works of San Francisco, who did a notable job of pioneering and building of floating washing plants; also, to Lord and Bishop, contractors of Sacramento, who were among the early operators, and to several others who built and rebuilt their plants until the weak spots were strengthened to take the beating required, and yet deliver a high degree of efficiency.

Jan 1, 1945

By J. E. Ryan

General Description Due to the extreme cold weather experienced in Flin Flon during the winter months, thought and precaution were necessary in the design of the plant buildings. The machine shop, carpenter shop, drill shop, and coal plant buildings are similar in the building materials used in their construction. They are sided with two-inch shiplap, insulated with celotex and asbestos paper, and covered with corrugated iron on all side-walls. Roofing consists of 2 by 4 lumber on edge, laminated, and further covered by celotex and three-ply roofing. These buildings are heated by means of unit heaters. The heaters are primarily steam-heated radiators, through which the air of the buildings is circulated by electrically-driven fans. Our machine shop is located to the east of, but central to, the main operating buildings of the mine and plant, and is so connected by a net work of tracks as to be able to serve all portions of the entire plant conveniently. The building is divided into two bays, the main bay 53 ft. by 340 ft., and the east bay 24 ft. by 340 ft. The shop office and drafting room, a two-story annex 24 ft. by 30 ft., is located on the west side of the shop. The arrangement within the shop is such as to house conveniently the several departments, namely, heavy machine tool section, repair floor section, boiler shop heavy tool and floor section, blacksmith heavy tool and forge section, tool room, electric welding rooms, stock room, tin and copper shop, and electrical parts and armature winding and repair shop (see Figure 1). All the heavy tools, the repair floor section, and railway tracks are so located in the large open bay as to be fully serviced by an electrically operated 15-ton bridge crane, with a span of 50 feet and a travel the full length of the shop. A standard-gauge railway track, branched off the main line, penetrates the full depth of the building. This track lies along the extreme east side of the main bay, allowing easy entrance and movement of rolling stock and heavy machinery, loaded on standard flat-cars, to the repair floors in the main bay. Eight jib cranes, affixed to building columns, further facilitate the heavy repair work throughout the various shop divisions. Our light and heavy machine tools are standard equipment, not unlike tools used in mine, mill, and railway shops.

Jan 1, 1935

By Paul F. Kerr, Donald M. Hausen

Fine colloidal gold near Carlin, Nevada is disseminated in leached carbonate strata of the Roberts Mountains Formation in the Lynn "window" of the Roberts Mountains thrust fault. The ore body is generally stratiform and is more or less conformable to altered beds near the top of the formation, underlying Devonian limestones. Two sequences of mineralization are recognized: ( 1) an earlier base metal-barite assemblage related to early Cretaceous intrusives (121 ± 5 m.y.), and (2) a later low temperature Au-As-Hg-Sb assemblage of near surface emplacement. The earlier sequence consisting of sparse galena and sphalerite in barite with anomalous amounts of zinc, lead, nickel and copper, associated with dikes of dacitic composition, is of little economic importance. The later sequence of gold, realgar, cinnabar, and stibnite associated with extensive silicification and argillic alteration of limestone beds, has resulted in important deposits of gold. Argillic alteration of hydrothermally leached carbonate strata has provided the environment in which the most prominent gold deposition took place. Carbonate minerals in the limestone host rock have been replaced by microcrystalline quartz and chalcedony to form stratiform silica masses and recrystallized lenses of euhedral quartz. Zones of porous silicification are light gray to white, elliptical in shape, and more or less follow bedding. Silicification is bordered by argillic alteration and pyritization. Deposition of gold usually lies in a zonal pattern that encircles chimney areas of silicification.

Jan 1, 1968

By W. R. Chambers

A wide variety of mining conditions exists within the South Midlands Area and across this range of conditions more than one half of the mines are highly susceptible to spontaneous combustion. Two thick seams in which the greatest risk exists are described and illustrated. The different heatings which take place are categorized by the locations at which they occur in the mines: additional special cases not easily categorized by location are discussed separately. The discussion for each category of heating follows the pattern of: (i) the reasons why it occurs; (ii) when it arises the means by which it is fought, and (iii) the preventive measures taken in an attempt to avoid its occurrence. Relatively new factors which may affect the incidence of heatings are highlighted and suggestions are made which may assist in reducing the number of incidents in the Area. A new method of continuous sampling, analysis and recording is described and mention made of an original method of interpreting carbon monoxide results with the aid of the computer. The first results from this work show that an early warning is given of an adverse change in trend several weeks earlier than with the present methods. Lastly, suggestions are made about the direction in which research might proceed to assist in reducing the special hazards created by several features inherent in the present methods of mining.

May 23, 1905

By David Montgomery

The feasibility of building a calibrator for the DuPont D-100 audio dosimeter is discussed. The desired specifications are used as guidelines but the possibility of their relaxation is also considered. Commercially available equipment is surveyed and found to not satisfy the guidelines. Several alternate concepts are investigated, and recommendations for further work are presented.

Jan 1, 1974

By Roger L. Beals, George A. Tweedy

I. INTRODUCTION. THE results of the cyanide-operations, given in detail in the following paper, show the progress that is being made at the Minas del Tajo. The old pan-amalgamation process, in operation up to and including 1905, while paying a profit on high-grade ores, was no longer able to treat profitably the ores in sight at that time, hence an alteration in the process was imperative. The success of this alteration is eloquently expressed by the following data Pan- Amalgamation. Cyanidation. 1905. 1907. 1903. Tons treated, . . 51,387 53,983 69,300 Value per ton (U. S. currency),. $10.75 $8.39 $8.28 Extraction, per cent., 65.00 88.50 S7.45 Extraction, per ton. .- $7.00 $7.4.; $7.24 Total cost, per ton treated, 6.50 4.311 4.01 Profit, per ton treated, . . 0.50 3.07 3.23.;

Feb 1, 1910

By John R. McWilliams

The technological and economic pattern of the U. S. mining industry has undergone a rapid and continuing change since World War II. To provide realistic up-to-date cost data and to disseminate knowledge of technical developments, the Federal Bureau of Mines, with the cooperation of individual mining companies, is presenting a series of mining methods and costs reports similar to those it issued before 1939. Shaft sinking has always played an important part in mine development and [ration] and is an appropriate subject for this series of reports. Shafts [are] especially important in areas such as the Coeur d'Alene district of Idaho, where every major mine is served by one or more shafts and shaft sinking is in progress at one mine or and her almost continuously.

Jan 1, 1960

By A. C. Fieldner

This is the tenth annual report of research and technologic work conducted by the Bureau of Mines on the occurrence, properties, mining, preparation, and uses of coal and coal products. These annual reviews are guide's to the current work-and publications of the Bureau but do not replace the more complete reports published under the authorship of the individual investigators on specific problems in Bureau of Mines bulletins, technical papers, reports of investigations, and information circulars and in the technical press. The Annual Report of the Director of the Bureau of Mines to the Secretary of the Interior for the Fiscal Year ended June 30, 1945, summarizes the year's work on coal as follows: Coal and Coal Products The United States maintained its No. 1 industrial position in supplying fuel for war and in preparing for peace through more complete mining, improved preparation and up-grading of coal for special uses, and better utilization of coal in industrial establishments and homes.

Jan 1, 1946

By Edward A. McClatchie

A methane monitor that complies with 30CFR75.313 has been designed and fabricated using a novel pressure modulated infrared absorption technique. The methane monitor met or exceeded in performance all of its target specifications. The monitor was operated continuously during production mining for the entire duration (45 days) of the in-mine test; no failures occurred during the test. The monitor was regularly checked with calibration gas and no shifts in calibration were found during the in-mine test. Operating principles, performance data and electrical schematics are included in the report.

Jan 1, 1976

By Robert E. Wallhagen

The froth foam seal topping system is part of a system for remote sealing of mine passages using flyash transported pnuematically from the surface. Making the final 5 percent of the seal with a foamed-in-place fire retardant polyurethane reduces the required flyash volume by 50 percent and provides a more reliable seal. Foam components are held at the surface under proper conditions of temperature and pressure; then conveyed down the borehole through individual hoses and mixed at the bottom with a static mixer. The polyol component is pre-mixed with fluorocarbon-12 which, when released from system pressure in the mixer, boils and causes the foam to expand. Difficulties in handling this particular foam formulation are offset by a flame spread index well below the 25 level by ASTM E-162 normally required for under-ground applications. Isocyanate, polyol (TDI) and catalyst are conveyed to the downhole package by three separate lines. Five additional lines operate the valving and convey solvent so that the mixer and package lines can be flushed immediately after foaming. The eight-hose bundle is provided in segments of several lengths so that bore-hole depths can be matched. Cast-in-place plastic cylinders hold the bundle together and transfer the weight of the hose through a special quick-release clamp to the crane's wire rope. The downhole package and hose bundle are deployed using a specially designed winch and crane system capable of borehole deployment to 1500 feet.

Jan 1, 1977

Many USBM research and information products are available through the systems or formats listed below: Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219 3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button o your fax machine. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. CD-ROM: This USBM disk is updated quarterly and sold by GPO's Superintendent of Documents. For information on the latest product, please contact Rodger Wedgeworth, 202/501-9557. Internet/World Wide Web: Text and graphics. Access via PC-based browsing software such as Netscape or Mosaic. Universal Resource Locator (URL) is: http:/www.usbm.gov Internet/Gopher Server Text and tables only. Using Gopher client software, access via port 70 as follows: gopher.usbm.gov Internet System Administrator: webmaster@usbm.gov (or contact your local System Administrator).

Jan 1, 1995

By Osvaldo A. Bascur, Curt Heftier

The lack of integrated information including the Energy/Utility Suppliers with sufficient detail for analysis causes inefficient operation in metallurgical complexes including the Energy/Utility Suppliers . Defining the right context for information use is essential for sustainable operations. This being said, what are we doing to enable people to act upon information and to be aligned to optimize the use of resources like raw materials, energy, water and consumables for an entire metallurgical complex? Collaboration between all company entities is a key component of improving efficiency. Evolution of web technology and object modeling of enterprise assets enables collaboration across the whole business. Operational troubleshooting occurs more quickly as the organization acts on issues to reduce wasteful operation. This paper presents a real time software infrastructure with tools that give users the ability to sift through available data, transform data into information for business continuous improvement and optimization. We will introduce a new technology for analyzing real time data, information and events using multidimensional analysis of information to detect anomalies based on the statistics of the data classified by time events to reduce the information into action. A new paradigm for collaboration at a local and strategic level is proposed to enable the enterprise to become proactive in dealing with wasted time and products. Three examples from the industry will presented and their benefits highlighted.

Jan 1, 2011

By F Minz, P Lamberg, A Mwanga, C Lund, C Wanhainen, M Amiri Parian, J Rosenkranz

A geometallurgical model is currently built in two different ways. The first and the most common way relies on geometallurgical testing, where a large number of samples are analysed for metallurgical response using small-scale laboratory tests, eg Davis tube testing. The second, mineralogical approach focuses on collecting mineralogical information over the orebody and building the metallurgical model based on mineralogy. At Lules University of Technology, Sweden, the latter method has been adopted and taken further in four ongoing PhD studies. The geological model gives modal composition by the help of element-to-mineral conversion and Rietveld X-ray diffraction. Texturally, the orebody is divided into different archetypes, and liberation measurements for each of them are carried out in processing fineness using IncaMineral, a SEM-based technique. The grindability and liberation spectrum of any given geological unit (sample, ore block, domain) are extrapolated from the archetypes. The process model is taken into a liberation level by mass balancing selected metallurgical tests using the particle tracking technique. The approach is general and can be applied to any type of ores. Examples of ongoing studies on iron and massive sulfide ores are given.CITATION:Lamberg, P, Rosenkranz, J, Wanhainen, C, Lund, C, Minz, F, Mwanga, A and Amiri Parian, M, 2013. Building a geometallurgical model in iron ores using a mineralogical approach with liberation data, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 317-324 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Frank L. Hess

"New England" and "granite" if not synonymous are at least associated terms. Where there are granites that are not deeply eroded there are usually pegmatites, the most erratic of rocks, and of them New England has a full portion. Many of the New England pegmatites contain the rare alkalis - lithium, rubidium, and cesium. however, the same in homogeneity of the earth's crust that has made the New England pegmatites unusual, in that so many of them contain the rare alkalis, has likewise made the distribution of the rare-alkali minerals sporadic even in those pegmatites, and most contain only enough to furnish collectors with more or less ornamental and uncommon minerals. New England has long had numberless collectors of minerals, and the mineralogists of its various schools have published many papers on the pegmatitic minerals, including those of the rare alkalis, but none of the papers have dealt with estimates of quantities. In this paper we have tried to place the emphasis on quantity rather than on mineralogy.

Jan 1, 1943

By Richard G. Stearns

Extensive thick lignite apparently lies within 250 feet of the land surface in Dyer, Lake, Lauderdale, Obion and Tipton counties. Information on geology, land use, soils, groundwater and instability is compiled, along with a bibliography. A test and monitoring site was investigated at Fort Pillow Prison in Lauderdale County. Analyses were made of lignite, overburden, associated water and leachate. Lignite has high BTU (about 7800) and low sulfur (1.1% avg.). A year or more of data are presented on rainfall, water levels, and chemistry of surface water, groundwater, leachate and water from test pits. Main potential environmental problems are quality of surface water, and possibly shallow groundwater. The main aquifer of the region will likely be un-affected by mining. Low transmissibility of shallow aquifers will minimize lowering water levels of wells. Soil reclamation and conservation should be readily accomplished, Dangerous earthquakes have a low probability and mines are not significantly more hazardous than steep bluffs.

Jan 1, 1981

By Charles L. Harness

The barite industry has made notable progress since the days when barite was used only as an adulterant in white-lead paints and the only method of mining it was with pick and shovel. The following chronological record may serve to show how this heavy white mineral has grown in importance in the national exonomy and at the same time to indicate development of methods for obtaining it. 1845. - Barite first, mined in Fauquier County, Va., for use as an adulterant in white-lead paints. 1850 (approx.). - French settlers 60 miles southwest of St Louis, Mo., discovered barite; called it "'tiff;' meaning white. It was mined and shipped to St. Louis for use in paint.

Jan 1, 1946