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By R. C. Buehl

A pyrometallurgical process for recovering manganese from open-hearth furnace slags or low-grade manganiferous iron ores is described. The slag or ore is smelted in a blast furnace to produce spiegeleisen; the speigeleisen is then blown with air in a basic converter to give an oxide slag. This slag product contains 60 to 75 percent manganous oxide and may be considered a synthetic manganese ore. In the smelting operations coke rates for five test periods ranged from 3,255 to 4,130 lb per ton of spiegeleisen. The recovery of manganese in the spiegeleisen varied from 60 to 76 percent. Recovery increased to 83 percent when the open-hearth slag feed to the blast furnace was diluted with a high-? grade iron ore sinter to facilitate smelting. In blowing the spiegeleisen a cyclic procedure was developed that gave nearly 90 percent recovery of manganese in the slag product (synthetic ore) yet prevented excessive contamination of the slag by phosphorus and iron. The overall recovery of manganese was about 75 percent when iron ore sinter was used with the open-hearth slag in the smelting step. The metal remaining after oxidizing the manganese from the spiegeleisen contained approximately 3.5 percent phosphorus. It was refined in a basic converter by blowing with air in the presence of lime" A high--grade iron and a basic phosphate slag were produced.

Jan 1, 1965

By J. A. Ruppert

The Bureau of Mines investigated methods of refining iron-contaminated zinc to marketable quality and developed a laboratory-scale process in which aluminum, added as a refining agent, reacted with the iron, forming solid Fe2Al which floated to the surface of the melt. Solids were separated by both filtration and centrifugation, using a unique type of "dipping" centrifuge devised during the work. Typical zinc recovery was 95 percent, and iron content of the metal was lowered from 0.37 to 0.02 percent.

Jan 1, 1967

By Oliver Bowles

The use of fire as a source of heat was the first step from primitive existence toward modern civilization, and heat has performed functions of inestimable importance throughout the ensuing ages. The first commercial steam engine invented in 1698 demonstrated that heat was an important source of power, and heat has since become the motivating force for railroad trains and steamboats as well as for machines in multitudes of factories. Aside from its function of supplying power, heat is an agent of vast importance in chemical reactions and engineering processes. Because of the high temperature of steam under pressure, losses by radiation from boilers and pipes become excessive unless the radiating surfaces are covered with insulating materials. Insulation is important also for hot-water pipes and many other types of equipment from which heat may radiate. Radiation losses from heated surfaces increase rapidly

Jan 1, 1943

By Xintan Chang

MFIRE is a computer simulation program that performs normal ventilation network planning calculations and dynamic transient-state simulation of ventilation networks under a variety of conditions. The program is useful for the analysis of ventilation networks under the influence of natural ventilation, fans, fires, or any combination of these. MFIRE simulates a mine's ventilation system and its response to altered ventilation parameters such as the development of new mine workings or changes in ventilation control structures, external influences (varying outside temperatures), and internal influences (fires). Extensive output enables detailed, quantitative analysis of the effects that the alteration will cause to the ventilation system. The program was developed at Michigan Technological University (MTU), Houghton, MI, with support from the Bureau of Mines. A personal computer (PC) version of the program was completed under contract for the Bureau by MTU. The purpose of this report is to document the installation and use of the PC version of the program MFIRE.

Jan 1, 1990

By Roger M. Sherman

[Investigation of mine land characteristics, evaluation of irrigation systems, and evaluations by the mining industry, determined that irrigation is a feasible method for aiding revegetation of coal mined lands in western arid and semi-arid regions. The various regions studied displayed a commonality of characteristics which enables, independent of the site or region, the recommendation of solid set irrigation. Irrigation should be supplemental by complimenting natural precipitation and be should implemented on a temporary basis.]

Jan 1, 1980

By Daryl R. Tweeton

The Bureau of Mines is investigating possible applications of geophysics to monitor leachate during in situ mining. Tomographic reconstruc-tion of seismic or electromagnetic crosshole data appears applicable. The tomographic program BOMTOM (Bureau of Mines tomography) was written and then used to investigate reconstructions with synthetic travel time data. The calculations confirmed that without constraints, crosshole data do not provide unique solutions. The solution is not determined solely by the data, but is also influenced by the velocity guesses starting the iterative solution procedure. The effectiveness of constraints in combatting nonuniqueness was examined. The requirement that the velocity not vary laterally at the top and bottom of the pixel grid was effective. This constraint is realistic when the top and bottom of the grid represent dry and saturated re-gions, respectively. Limiting the maximum velocity improved reconstructions, but may not be applicable in practice. BOMTOM uses the simultaneous iterative reconstruction technique (SIRT) with straight ray paths. The program is efficient in use of memory, and can be run on a personal computer. A source code in FORTRAN is listed. A source code in BASICA and compiled executable codes in both languages are available from the Bureau's Twin Cities (MN) Research Center.

Jan 1, 1985

By Gordon R. Sima

This contract is concerned with feasibility studies, design and fabrication of a prototype hand-held test instrument and a machine-mounted test Instrument for measurement of electrical shock hazards of mining machines. This report presents the proposed and detailed design of the hand-held test instrument and the machine-mounted test instrument. Theory of operation of each instrument is discussed and includes the operating parameters.

Jan 1, 1976

On September 4, 2007, Mine Safety and Health Administration, in alliance with the International Union of Operating Engineers and the International Association of Bridge, Structural, Ornamental, and Reinforcing Iron Workers, presented the first annual Mine Construction Maintenance and Repair?s Safety Contractor of the Year Award to Artisan Contracting, Inc., of Cape Girardeau, MO. Eligible contractors located throughout the United States were nominated. Artisan Contracting was nominated by Illinois Cement Company located in LaSalle, IL. Illinois Cement Company is a Division of Eagle Materials Inc., located in Dallas, Texas. Mr. Larry Frankum President of Artisan Contracting Inc., stated, ?While it is gratifying to receive a wonderful award such as this, we must not forget how fragile a good safety record is. We must constantly remain diligent in pursuit of maintaining safe work sites.?

Feb 1, 2008

By Oliver Bowles

"Underground operation.In its broader sense the term ""mining"" is applied to all processes whereby raw materials are taken from the earth to be used as sources of mineral products. In a more restricted sense ""mining"" is applied to underground operations as contrasted with open pit work designated as quarrying. The tern is used in the restricted tense in this paper; for it relates to the exploitation of limestone deposits by modern methods of underground operation rather than by open pit methods.Present tendency toward miningIt may seem to some readers that a paper on mining limestone will find little general interest among lime plant operators, for only a limited number of them have yet resorted to this means of procuring raw materials. It is noteworthy, however, that a growing tendency exists toward underground operation, for one by one quarry owners are faced with increasing difficulties in open pit operation. It seems desirable, therefore, for operators to keep closely in touch with this gradual change in process, to inquire into the underlying causes, to compare costs, and to study the effects of the change in method on subsequent steps in calcining the stone to produce lime."

Mar 1, 1924

By D. Pennington

Ground-water levels and subsidence have been monitored over a longwall panel of a deep coal mining operation located in western Pennsylvania. The monitoring network includes eleven ground-water monitoring wells completed to measure water level changes in separate shallow and deep aquifer zone-, and 50-foot surveyed subsidence stations parallel and perpendicular to the panel centerline. Monthly monitoring data were collected during the premining, mining, and postmining tine periods. Aquifer testing and borehole geophysical logging were conducted during premining, and post-mining conditions to document any changes in aquifer properties and ground-water flow patterns. Results indicate ground-water declines were located with respect to the mining face and mined longwall panel. Dewatering of the deep aquifer zone caused a significant water level decline in deep wells; however, the shallow aquifer zone was isolated fro major impacts by an aquitardal layer during, the, one-year period. Transmissivity data were greatly impacted by fracturing, in the highly anisotropic aquifer system. Borehole geophysical logging indicated changes in ground-water flow patterns and zones of increased fracturing from subsidence.

Jan 1, 1984

By P. L. Russell, M. E. Volin, F. L. C. Price, D. H. Mullen

Tin deposits in Catron County, New Mexico, were explored by the Bureau of Mines under authority of the Strategic Minerals Act of August 1939. The investigation covered both lode and placer deposits and was later extended to deposits in Sierra County. Six of the known deposits were examined by E. D. Gardner, supervising engineer of the Southwest Experiment Station of the Bureau of Mines, and S. G. Lasky, a geologist of the Federal Geological Survey, in June and July 1939. It was recommended that the more promising occurrences be explored by test pitting, trenching, and sampling. Field work, under supervision of M. E. Volin, began in September and continued through December 1939. The area was mapped by Carl Fries, Jr., of the Federal Geological Survey, in 1939 and 1940. The La Cruz Development Co. acquired control of the Squaw Creek placer claims in 1942 and began active sampling and development preliminary to large-scale operations. The result of this work showed a considerably higher tin content than that found by the Bureau of Mines in 1939. Because of this report and reports from other parts of the district that large-scale operations for the production of tin from lode deposits were possible, it was recommended that the Bureau of Mines resample parts of Squaw Creek and conduct a mill test of lode material to determine whether a concentrate could be made that was high enough in tin and low enough in iron to be acceptable in American smelting practice. This work, under the supervision of Paul L. Russell, was begun in November 1942 and completed in January 1943, during which time the Sierra Metals Co. acquired control of a large area in Sawmill Canyon. At the suggestion of the Federal Geological Survey and the War Production Board, which had reason to believe that a great deal of commercial material existed on certain flatlands and gully slopes, the project was extended to include test pitting and sampling of those areas. This work was completed in February 1943.

May 1, 1947

By Laurel A. Powers

The Bureau of Mines process for recovering Ni and Co from low-grade domestic laterites uses a reduction roast followed by an ammonia, ammo-nium sulfate leach. This investigation examined the waste streams of the process for their potential environmental impact and focused on the laterite residue produced. The U.S. Environmental Protection Agency's extraction procedure (EP) toxicity tests and column leaching showed that leachable metal concentrations would be low enough so that the residue would not be considered a hazardous waste under present definitions. Under nonacid leaching conditions, about the same amount of metal was extracted from laterites as from their residues, and the leachates were similar to water samples from an undisturbed laterite deposit. Washing tests on the laterite residue showed that ammonia and ammonium sulfate concentrations were reduced according to equilibrium stage calculations, resulting in residues that would be acceptable for revegetation. With water washing only, the residue would not be considered a hazardous waste even though significant amounts of Ni and Co were absorbed from entrained leach solution onto the residue. Washing first with fresh leach solution and then with water prevented this absorption and thus improved the overall metal recovery.

Jan 1, 1983

By A. Renton Amell

The rate of dissolution of U02 was measured in acid solutions similar to those used for in situ leaching, with S04 of 10-1.82 to 10-4 M, Fe(III) of 10-2 to 10-4 M and pH's of 1.1 to 2.3. The dependence of dissolution rate on pH was small and inconsistent, probably reflecting the combined effects of a very weakly polar oxidizing complex, probably FeSO4+, and a nearly neutral U02 surface. Differences in the state of the U02 surface may explain this variability as well as contrasts between these results and results reported in other work. Changing either S04 or Fe(III) concentrations significantly affects dissolution rates. Increasing low sulfate concentrations in solutions containing 10 2 M Fe(III) at pH 2 results in formation of FeSO4+. In such solutions, rates increased with (S04)/(Fe(III)) up to 1:30, thereby indicating that the oxidation of U02 by FeSO4 is more rapid than by Fe3+. However, the dissolution rate decreased at higher (SO4)/ (Fe(III)), due either to sorption of SO42- on the UO2 surface or to formation of other less reactive sulfate complexes such as Fe(S04)2 or FeHSO4+ However, Fe(III) concentration is the dominant factor in determining solution rates. The rate was directly proportional to ferric iron concentration, indicating that the rate-determining step of the dissolution reaction is a single-electron oxidation by a ferric complex. Dissolution rates were lower in solutions of 0.1 and 1.0% H202 (0.029 and 0.29 M) than at similar concentrations of ferric iron because of formation of an insoluble surface coating of uranium peroxide, UO4?4H20. This phase may limit the value of hydrogen peroxide as an oxidant in lixiviants, not only by its very low solubility, but perhaps also by filling pores and reducing permeability in the ore body.

Jan 1, 1978

By Jane Applegate

This report documents efforts to design, develop and test a training approach which would assist front-end loader operators in the acquisition of skills and awareness to reduce the probability of their involvement in accidents in the mining environment. The goal of this project was to prepare and use (on a trial basis) a training method and materials which would be generally applicable to any loader and surface mining operation while at the same time, be adjustable by mine personnel to meet the specific needs of each mining operation. This effort resulted in the Front-End Loader Training System, a structured, performance-based training approach with diverse instructional aids and classroom and on-machine training experiences. Validation of the System at a large western mine demonstrated the utility and flexibility of the training approach and materials.

Jan 1, 1983

By C. A. Geffen-Fowler

This report, sponsored by the Bureau of Mines, presents the results of an examination of the safety of the Blind Shaft Borer (BSB) shaft sinking system and an alternative modified BSB design concept in comparison to conventional shaft sinking technology. Detailed study of the two systems was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the BSB systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the two BSB systems was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that both BSB systems are safer than conventional shaft sinking. The potential risk of conventional shaft sinking operations could be reduced by over 30%, on the average, with the use of the original BSB system, and by an average of about 10% with the modified BSB. Design change recommendations to further improve the safety of these systems include better fire suppression systems, improved man haulage systems and more compact hydraulics. An operational safety manual was also developed for the modified BSB system.

Jan 1, 1981

By F. D. Cannon

"In metal and nonmetallic mineral mines during the 15-year period 1911 to 1925, 30.17 per cent of all fatalities and 16.57 per cent of all injuries were caused by falls of rock or ore from the back or roof or from the wail; 1.24 per cent of the fatalities and 11.05 per cent of the injuries were caused by rock or ore while loading at the working face; 6.66 per cent of the .fatalities and 2.49 per cent of the injuries resulted from men falling down 3 chute, winze, raise, or stope; and run of ore from chute or pocket caused 1.48 per cent of the fatalities and 1.93 per cent of the injuries.3 Hence, accidents due to falls of men and material caused. 39.55 per cent of the fatalities and 34.05 per cent of the injuries in these mines. Accident prevention can best be assisted by each company's preserving complete records of accidents classified according to cause and rate per thousand or 10,000 shifts. A systematic method of recording accidents and the employment of graphs or charts will be helpful to the company safety department in analyzing the cruses of accidents. The purpose of this publication is to analyze data on accidents caused by falls of men and material in metal -mines of the United States, and to suggest methods of preventing or reducing such accidents."

Jun 1, 1929

By Donald W. Mitchell

Studies were made in the Bureau of Mines Experimental coal mine to evaluate the effectiveness of a few extinguishing agents and techniques for controlling a fire on a simulated mining machine. The investigation showed that water containing an alkali-metal salt or a surface-active (wetting) agent was more effective than water alone. For close attack, fog applications was the most effective technique studied; high rates of agent application controlled the fire more quickly than low rates. The ability to control the fire increased as the distance of attack decreased. Dry powders controlled the fire when applied by shovel but not when applied airborne by rock-dust distributor or by hand fire extinguishers. Dry alkali-metal salt powders (potassium and sodium bicarbonates and sodium tetraborate) quenched the fire more readily than limestone dust. In each instance the finer powder, the greater its effectiveness. In an open ventilated entry, smoke and hot gases backed against the air currents. An airspeed of 230 feet per minute was required to permit approach to within 10 feet of the fire. At lower airspeeds, approach could be made by extending the brattice across the bottom two-thirds of the entry, by pushing the smoke ahead with water sprays, or by discharging dust from a rock-dust distributor. In a dead-end entry, the fire was approached to within 30 feet by coursing fresh air along an airtight line brattice; however, it was safer, easier, and less time-consuming to attack the fire from a fresh-air base 100 feet away with a solid stream or by high-expansion foam; the latter method was more effective.

Jan 1, 1961

By R. S. Dean

The function of the Metallurgical Division is to conduct investigations relating to the treatment of mineral products from the state in which they are mined to the refined metal or other unfabricated product. These investigations include scientific and practical studies of ore dressing, covering the crushing and grinding of ores, separation by gravity, flotation. and magnetic methods; the hydrometallurgical treatment of ores, including cyanidation and amalgamation of the precious metals; the smelting and refining of copper, lead, and zinc, as well as the rare metals; and steel-melting practices from the raw ore to the finished steel. The object of this work is to conserve natural resources and eliminate waste by furnishing information on current methods of metallurgical practice. making fundamental studies of metallurgical processes, and developing new processes to the point of demonstrating their practicability. The Division is made up of sections devoted to the several phases of this work, each section being headed by an investigator capable of supervising his particular work. The work is carried on at the experiment stations and field offices or in the field, whichever seems best suited for the work in hand. The following, projects should be mentioned as particularly outstanding among those consummated successfully during the year: 1. Application of the type of chemicals known in the textile industry as wetting-out agents to flotation and agglomeration of ores, particulary soluble salts such as sodium and potassium chloride which must be treated in saturated brine. 2. Demonstration or a linear relation between surface and coercive force in magnetic minerals and Its application to magnetic separation and to the determination of grinding efficiencies and other metallurgical data which require surface determination at very fine sizes. 3. Pilot-plant demonstration of the practicability of the reduction of iron ore by natural gas and conversion of this direct iron into steel by direct melting and by forging and rolling before melting. The structure and properties of the iron so produced were studied in detail. This report covers the fiscal year July 1. 1934, to June 30, 1935.

Jan 1, 1936

By R. S. Dean

The function of the Metallurgical Division is to conduct investigations relating to the treatment of mineral products from the state in which they are mined to the refined metal or other unfabricated product. These investigations include scientific and practical studies of ore dressing, covering the crushing and grinding of ores, separation by gravity, flotation, and magnetic methods; the hydrometallurgical treatment of ores, including cyanidation and amalgamation of the precious metals; the smelting and refining of copper, lead, and zinc, as well as the rare metals; and steel-melting practices from the raw ore to the finished steel. The object of this work is to conserve natural resources and eliminate waste by furnishing information on current methods of metallurgical practice, making fundamental studies of metallurgical processes, and developing new processes to the point of demonstrating their practicability. The Division is made up of sections devoted to the several phases of this work, each section being beaded by an investigator capable of supervising his particular work. The work is carried on at the experiment stations and field offices or in the field, whichever seems test suited for the work in hand. The following projects should be mentioned as particularly outstanding among those consummated successfully during the year: 1. Application of the type of chemicals known in the textile industry as wetting-out agents to flotation and agglomeration of ores, particulary soluble salts such as sodium and potassium chloride which must be treated in saturated brine. 2. Demonstration of a linear relation between surface and coercive force in magnetic minerals and its application to magnetic separation and to the determination of grinding efficiencies and other metallurgical data which require surface determination at very fine sizes. 3. Pilot-plant demonstration of the practicability of the reduction of iron ore by natural gas and conversion of this direct iron into steel by direct melting and by forging and rolling before melting. The structure and properties of the iron so produced were studied in detail. This report covers the fiscal year July 1, 1934, to June 30, 193b.

Jan 1, 1936

By Lawrence H. Roth

Past failures of coal refuse embankments have resulted in more intensified efforts in inspections of coal refuse sites. Inspections, however, are mainly qualitative and time consuming. In August 1975 CH2M HILL was awarded a contract to identify, develop, and test a rapid system for monitoring coal refuse embankments to aid in inspections. The rapid monitoring system developed uses convergent and vertical photography from conventional fixed-wing aircraft. The system was tested on an active landslide and on two coal refuse facilities using both black and white and color infrared film. Field tests showed the system was capable of accurate measurement while providing qualitative data through photointerpretation. The accuracy of the system allows it to be used to monitor coal refuse embankments, tailings dams, major earth dams, and natural slopes. Bibliographies of literature reviews in the area of past coal refuse embankment failures, monitoring instruments and methods, and photogrammetry are included.

Jan 1, 1977