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By Normal Seidle

This report (rind related Appendices) provides a description of the functional design specifications and related rationale for development of a training system for dragline equipment operators. Phase I activities involved a delineation and detailed analysis of specific behavioral requirements for successful dragline operation. Following the field data collection effort, job/activity/task descriptions were formulated into training requirements which can be achieved by a trainee with training hardware having specific functional capabilities. The training system analysis integrated the training requirements and the trainer functional capabilities into recommendations which configure a total training system. The objective of the training system described in this report is to provide new operators of dragline equipment with the requisite skills and knowledge to assure cost-effective development and an adequate supply of our human resources.

Jan 1, 1975

By Fun-Den Wang

This report presents theoretical studies and experimental work dealing with the detection of dangerous roof and pillar conditions in underground mines through measure¬ment of temperature differences on the surface of the mine opening. The theoretical work is directed at modeling the circumstances where a loose slab of rock might be detected. The experimental work provides input data for the theoretical models. At the beginning of the project, little was known by the authors of the conditions that would permit detection of a loose slab of rock or coal by measuring the surface temperature differences. The U.S. Bureau of Mines had found that there were detectable surface temperature differences on the roofs and pillars of mines. The Bureau contracted with Colorado School of Mines to measure temperature profiles around mine openings in an effort to learn if the temperature differences they had detected were directly related to loose pieces of roof and pillar rock. The Bureau was principally interested in learning if loose rock could be found in coal mines by measurement of surface temperature differences with an infrared thermometer.

Jan 1, 1972

By W. C. Babcock

This report covers Phase V of .a continuing program to apply a new liquid membrane process called coupled transport to the recovery pf metals from hydrometallurgical leach solutions. During this phase of the program, a membrane system of moderate scale was constructed and field-tested at the Exxon Highlands Mine and Mill Co. site near Douglas, Wyoming. The test unit contained four hollow-fiber membrane modules, each with 100 ft2 of membrane area. In the field tests, about 1000 gallons per day of leach solution was processed. The unit was operated on the leach solution for about 50 days. Leach solution entering the unit contained 100 ppm uranium. This concentration was reduced to about 5 ppm by coupled-transport treatment, and the uranium was concentrated to about 2 wt% as a uranyl carbonate product. Under these conditions, a transmembrane uranium flux of about 2.5 lb/ft2-year was obtained. An economic analysis showed that the cost of recovering uranium from this leach solution via coupled trans-port is about $1.20/lb. At higher concentrations of uranium in the leach solution this cost is reduced. For example, at 1000 ppm the cost of uranium recovery is about $0.30/lb.

Jan 1, 1983

The Bibliographic Data Base contained in the present volume is the result of a literature search conducted as one task of the Bureau of Mines project concerned with research in borehole assay technology. The data base includes articles, symposia, books, corporate and government reports, patents, and other literature concerned with some aspect of borehole logging, from January 1969 through December 1975. Occasional updating to keep the data base current is anticipated. The remainder of the intro¬duction will be devoted to the explanation of the organization of each entry, along with the translation of terms and abbreviations used in the text. Each entry contains six sections. These include an ID code, a title, an author section, a source section, an abstract, and a descriptor section. The first item listed in an entry is the ID code. This serves to identify an entry. It consists of the first six characters of the first author's (or editor if no authors are involved) last name, along with the last two digits of the year of publication. A letter sometimes follows the year of publication to assure a unique alphanumeric code. For example, if an author named Wilson writes more than one piece of literature in a given year (for example, 1972), the ID code for the entries identifying these pieces of literature would be identical. Therefore, to allow for unique ID codes, the first piece would he identified as "WILSON 72,', the second piece as "WILSON 72A", the third "WILSON 72B", and so on.

Jan 1, 1976

This Bureau of Mines publication contains the texts of the four papers presented at the May 6-7, 1980, seminar on the role of overburden analysis in surface mining. Coverage includes the geologic distribution of pyrite and calcareous material and its relationship to overburden sampling, overburden sampling and analysis, use of soil-overburden data in mine planning and development, and minesoil classification.

Jan 1, 1981

By P. M. Daling

This report, sponsored by the U.S. Bureau of Mines, presents the results of an examination of the safety of the impactor shaft sinking system in comparison to conventional shaft sinking technology. Detailed study of the impactor system was also performed to identify and recommend design changes for optimum safety conditions. A comparison of the impactor machine and its support systems with conventional shaft sinking was made on the basis of relative risk levels. Risk incorporates measures of both the frequency and the potential consequence of accidents. A safety evaluation of the component operations of the impactor shaft sinking system was performed using a Failure Modes and Effects Analysis (FMEA) methodology. The results of this analysis show generally that the impactor shaft sinking system is safer than conventional shaft sinking. The potential risk of conventional shaft sinking operations could be reduced by an average of over 35 percent with use of the impactor shaft sinking system. Design change recommendations to further improve the safety of the impactor system include a revised fire suppression system, improved access to and from the operator cabs, reliable noise attenuation measures, and improved communication systems. An operational safety manual was also developed for the impactor shaft sinking system.

Jan 1, 1982

By E. J. (Kirk) Conway

The objectives of this project were to: (1) determine the extent to which maintainability design concepts and principles have been applied to the design of underground coal mining equipment, (2) try to assess its impact on productivity and personnel safety, and (3) develop maintainability guidelines to enhance the design of new or rebuilt equipment. An equipment design review was completed at ten operational coal mines. The purpose was to identify design approaches and features that enhanced and degraded the maintenance process. Mine management, safety, and maintenance personnel were also interviewed to identify machine specific design problems. Six original equipment manufacturers were visited and the procedures used to enhance the maintainability of Their equipment discussed. Volume I of the Final Technical Report presents an overview of procedures and protocol used and a summary of the findings. Volume II includes the maintainability design guide for mobile underground mining equipment.

Jan 1, 1988

By W. H. Somerton

Many oil-producing formations contain significant amounts of clay. Because of the large surface area and reactivity of such surfaces, the response of the formations to various recovery processes may be dominated by the reactions of fine-grained minerals, including clay minerals, in the formations. Thus, the success or failure of enhanced oil recovery (EOR) methods may be controlled to a large extent by the amount and nature of these minerals in the formations to which the methods are being applied. One of the deterrents to the successful application of chemical EOR methods is the loss of chemicals injected into the formation, to non-oil recovery processes. These chemical loss processes include adsorption onto mineral surfaces, chemical reactions with rock and fluids in the formations, possibly leading to precipitation and plugging of the formation, and trapping of chemicals in parts of the rock structure so that they become unavailable for displacing oil. Chemicals that may be injected include surfactants, polymers and caustic solutions which react with organic acids in the crude oil to produce surfactants in-situ. These losses are most pronounced in fine-grained reservoir rocks containing substantial amounts of clays.

Jan 1, 1984

By L. C. IlsLey

In January, 1922, a conference relative to trailing cables for use with permissible mining machines was held at the Pittsburgh Experiment Station of the U. S. Bureau of Mines. At this conference it was recommended that the bureau take steps to investigate the rubber-sheathed type of cables and to bring about the establishment of a list of approved cables. Effective until such time as a complete investigation could be made, the bureau asked the several manufacturers holding approvals for mining machines to recommend cables for use with their machines. In general the cables recommended were tentatively approved. Due to the lack of available personnel, no actual tests of cables were made until mid-1927. Meanwhile a field investigation of trailing cables was made at 20 mines of three coal companies in western Pennsylvania, and samples of cables were obtained from the manufacturers for laboratory tests. Twenty-five samples of the concentric-type cable, representing the product of five manufacturers, were obtained for the tests. These cables were of four sizes, as follows: 3 cables of No. 2 B & S gage, 17 cables of No. 3 B & S gage, 3 cables of No. 4 B & S gage, and 2 cables of No. 6 B & S gage.

Jan 1, 1929

By Felix duBreuil

The present sampling procedure for evaluating the rock dusting conditions in a coal mine is time consuming. This study considers means by which this procedure could be simplified. Surveys were conducted in six coal mines in Pennsylvania to determine the in¬combustible content of the deposited dust. Some 2,000 samples were analyzed and statistically evaluated. It is suggested that the mean incombustible content could be obtained with fewer samples and smaller samples without greatly increasing the sampling error.

Jan 1, 1972

By E. D. Eastman

There are three researches upon the specific heat of water vapor by the method of explosion that are sufficiently advanced in technique and suitable in plan to justify careful study of their results , with the double purpose of fixing the best available experimental values and indicating the attainable accuracy of the method. These three researches comprise the work of Pier , Bjerrum , and Siegel.5 The work of earlier date than Pier's suffers from obvious inaccuracy of measurement , while the experiments more recent than Siegel's , such as those of Womersley6 , of Bone and his collaborators , and of Maxwell and Wheeler , 8 are for the most part not well designed for the accurate determination of the heat capacities in question . Some of the errors to which they are especially subject have been discussed by David and by David and Thorp.

Sep 1, 1930

By Wils L. Cooley

The report covers several aspects of mine safety ground systems, primarily for underground coal mines. The design of a combined ground fault-ground check monitoring system is presented. An analysis is made of grounding systems for dc shuttle cars. Complete resistance data and results of physical inspections of self-salting ground rods are presented. A detailed resistance and economic analysis is presented for the use of composite materials for building inexpensive and effective ground beds in high-resistivity areas. The desireability of penetrating the coal seam with a borehole safety ground is investigated. A report is made of a Mine Substation Grounding and Bonding Workshop.

Jan 1, 1980

By E. G. Davis

This report summarizes an investigation to determine the occurrence and recoverability of heavy minerals in sand and gravel operations in the Southeastern United States. A total of 61 samples from 34 sand and gravel operations in Alabama, Georgia, South Carolina, and North Carolina were studied. Heavy minerals, in amounts ranging from 3 to 400 pounds per ton, were found in all of the samples. Eighty percent of the samples contained 20 to 40 pounds per ton of heavy min¬eral. Valuable heavy minerals, in order of decreasing amounts, were ilmenite, kyanite, zircon, rutile, and monazite. Large-scale concentration tests were made on five samples from four major producers. Gravity concentration by Humphreys spirals and tables resulted in bulk heavy mineral concentrates that graded from 82 to 98 percent total heavy minerals. Mineral recoveries ranged, in percent, as follows: Ilmenite 60 to 95; zircon 96 to 100; kyanite 37 to 77; rutile 89 to 100; and monazite 96 to 100. Separation studies on the gravity concentrates showed they would respond to high-tension and high-intensity magnetic separation techniques to produce individual mineral concentrates. The recovery of each individual mineral from fractionation of the heavy mineral gravity concentrates, in percent, was: Ilmenite 77 to 94; rutile 41 to 68; kyanite 62 to 79; zircon 49 to 83; and rare-earth products, monazite and xenotime, 42 to 96. The grade of each mineral concentrate was: Ilmenite 51.1 to 68.7 percent Ti02; rutile 93.7 to 94.3 percent Ti02; kyanite 55 percent A1203; zircon 58 to 61 percent Zr02; and rare-earth products containing 73.8 to 90.8 percent monazite and 4.8 to 12.7 percent xenotime.

Jan 1, 1971

By J. R. Nettle

The development of a process for upgrading offgrade titanium metal by electrorefining in molten salt led to an investigation of the electrotransfer characteristics of selected metals when alloyed with the titanium to be refined. Previous tests on seven binary titanium alloys showed that the degree of transfer of the alloying constituent depends on the constituent and on the operating procedurese.5 This report describes tests on electrorefining ternary mixtures of titanium with selected metallic elements. Ten alloys were prepared from high purity titanium and 2-1/2 percent of each of the metal pairs selected from the same elements used in the binary study; manganese, vanadium, chromium, zirconium, tin, molybdenum, aluminum. Operating variables were similar to those investigated in the binary alloy study that gave minimum alloy metal transfer. The data presented indicate the transfer characteristics of the various metals and combinations tested relative to each other.

Jan 1, 1962

By D. E. Kirby

In line with the Bureau of Mines' goal of providing technology to maintain a supply of minerals adequate to meet national economic and strategic needs, a method for recovering chromite from lateritic materials was investigated. Laterites are a large resource of Ni, Co, and Cr, critical metals of which the United States has insufficient domestic sources. A roast-leach method was developed by the Bureau to extract nickel and cobalt from domestic laterites. A concurrent effort was made to recover chromium from either unprocessed laterites or the leach residues. This report characterizes laterites and laterite leach residues. It describes a chromite recovery procedure using conventional industrial beneficiation equipment for sizing, low-intensity magnetic separation, and gravity concentration. Concentrates containing 20.0 to 22.4 pct Cr (29.0 to 32.7 pct Cr203) and with a 1.6:1 to 1.9:1 Cr-Fe ratio were recovered from laterites and residues containing 1.3 to 2.5 pct Cr with recoveries exceeding 50 pct. Because of their low grade and fine size, these concentrates would be suitable for preparing chromium chemicals. The direct beneficiation of laterites for chromite recovery resulted in the minerals containing nickel and cobalt concentrating in slime products. No iron oxide coproducts of acceptable grade were recovered from either laterites or residues.

Jan 1, 1982

By Thys B. Johnson

The mine system analysis and evaluation study presented in this report was part of the U. S. Bureau of Nines' Tertiary channel project conducted under the Heavy Metals program. The Badger Hill pit, located on the west end of the San Juan Ridge area, near Nevada City, California, was the site of the Bureau's field work. The objectives of this study were: (1) Determine potential alternative mining systems for some of the large tertiary channel gold-bearing gravel deposits, and (2) Identify areas of technology where further investigation would be merited because of their potential inclusion in a mining system for such deposits, The study involved the development of a mineralized block inventory, an economic block inventory, determination of optimum ultimate mining limits and a preliminary economic mining system evaluation. Computer programs were developed and utilized for each of the study phases stated above. The sampling program conducted at Badger Hill by the Bureau Delineation Group together with confidential drill hole data provided by the San Juan Gold Co. formed the basic gold values and distribution information from which a deposit model was developed. The deposit was divided into minable block units and net economic values were assigned to each block for various configurations of both open-pit and underground mining methods based on cost and performance data provided by the various Bureau of Mines Research Centers. A number of controllable variables such as: (1) Mining method (open-pit and underground), (2) depth of mining cut, (3) production rate and (4) equipment type and capacity were evaluated. The prime measures of effectiveness on which the mining systems where judged were discounted cash flow rate of return and maximum utilization of natural resources. The analysis showed that underground mining of the Six-Mile Tertiary channel gold-bearing gravel deposit under consideration was uneconomical and did not permit maximum recovery of the resources within the channel. It was also apparent that mining the Six-Mile Deposit for gold alone is uneconomical or at best marginal at a gold price less than $80 per ounce. The analysis showed that the potential for an economic mining operation within the Six-Mile Deposit exists when the gravel resources of the channel are considered together with the gold. It was determined that the highest rate of return would be realized with a 20-year open-pit mining operation yielding 745,000 ounces of -gold and 55 million cubic yards of usable gravel.

Jan 1, 2012

By E. R. Maize

This report is the third of a series on convergence of roof and floor in coal mines and subsidence of surface that accompanies it. The first papery dealt with extraction in a mechanized mine (Montour 10) having relatively short rib lines that retreat rapidly. The second 6/ dealt with extraction in a mine (Crucible) in which coal was loaded by hand and in which the rib lines were long and slow-moving. The present report deals with a mine (Gibson) in which conditions approximated those in the Crucible mine, except that the distance between room centers was considerably less and the pillars were narrower in consequence. Moreover, the average cover was less and the studies were made under the steep hillside of a stream valley compared with a gently rolling surface over the portions of the second mine studied. Gibson mine lies in the east-central part of Washington County, Pa., approximately midway between the Montour 10 and Crucible mines on a north-south line. A cooperative agreement covering the work was made with the Hillman Coal & Coke Co. through W. L. Affelder, vice president. This paper describes the methods used in the investigation, gives excerpts from the data obtained, and offers such generalisations as appear to be justified.

Jan 1, 1940

By Allen S. Smith

Analysis of the helium content of a natural gas presents more than the usual difficulties encountered in applying the thermal-conductivity method because of the relatively small amounts of this inert as present and the wide variation in the other constituents. However, the numerous advantages of this method and its adaptability to Continuously recording and control instruments make it worthy of consideration. A specific application of the method described yields quantitative results only when used with gas mixtures of known qualitative compositions which Vary within predetermined limits. Periodic analyses for the helium content of a producing gas well may be conveniently made by an absorption method, and a continuums analytical method is not necessary for this purpose. Natural gas containing 1.75 to 1.90 percent of helium produced from Government-owned wells is processed in the Amarillo (Texas) Helium Plant of the Bureau of lanes. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company. As complete recovery of the helium in the raw material is not economically practicable, the processed gas contains 0.1 to 0.3 percent of helium, depending upon conditions of operation. Production is checked against the helium removed from the gas, which before the installation of the thermal-conductivity apparatus was calculated from the analysis of a cumulative sample of the processed gas. As conditions of operation affect the residual helium content to a large extent, a composite sample was an uncertain index of the efficiency of the process.

Jan 1, 1934

By J. Dean Warner

From 1984 through 1987, the Bureau of Mines investigated numerous prospects and new discoveries of columbium, rare-earth elements (REE), uranium, zirconium, and other metals associated with the multi-phased peralkaline granite at Bokan Mountain, southeastern Alaska. This report summarizes the mineral evaluations and estimates indicated and inferred resources for those prospects containing significant tonnage and grade. A total of approximately 96.2 MM lb Cb205 (43 pct of the tonnage at a grade exceeding 0.125 pct Cb205), and 11.8 MM lb U308, 27.9 MM lb Th02, 133.0 MM lb Y203, 637.6 MM lb ZrO2, and 241 MM lb REO are estimated to be contained within nine deposits totalling 37.8 million tons (at least 80 pct of resource tonnage also exceeds 0.5 pct Y203 + REO). Generally, half of the REO content is composed of the heavy yttrium subgroup. Several deposits also contain beryllium and tantalum; 2.1 MM lb of Ta205 and 8.9 MM lbs of BeO were estimated. These estimates would likely be substantially increased with additional exploration. Four deposit types were investigated; shear zones and fracture-related deposits, pegmatites, mineralized dikes, and placers. Mineralized dikes contain most of the beryllium, columbium, tantalum, yttrium, zirconium, and REE resources, whereas shear zones and fracture-related deposits (Ross-Adams mine) contain the principal of the uranium resource. Pegmatites are similarly mineralized as are dike deposits, and contain low levels of gold. Placer potential is suggested, but no deposits were found.

Jan 1, 2011

By Max L. Glenn

As part of its goal to minimize requirements for mineral commodities through conservation and substitution, the Bureau of Mines conducted research to develop molybdenum as a potential substitute for superalloys containing the strategic and critical materials, nickel, chromium, and cobalt. Since molybdenum requires protection from oxidation at high temperatures, several complex oxides of the spinel and perovskite structure were investigated to determine which possessed the greatest potential for use as oxidation-barrier coatings. Two spinels (MgCr204 and MgA1204) and five perovskites (BaHfO3, YCrO3, NdCrO3, BaZrO3, and LaCrO3) were selected for testing. Various high-temperature prop¬erties that are important for oxidation-resistant coatings were examined, including diffusion rates of oxygen and molybdenum, recession (vaporization) rates, hardness, erosion resistance, sinterability, reactivity with molybdenum, and ease of application. From the evaluation of high-temperature properties, two spinels (MgCr204 and MgA1204) stand above the other oxides as possible coatings for molybdenum. However, laboratory coatings of MgCr204 at 1,360° C (2,480° F) are equivalent or inferior to currently available MoSi2 coatings; laboratory coatings of MgA1204 may be comparable under limited conditions to currently available MoSi2 coatings at the same temperature.

Jan 1, 1979