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By Scott A. Stebbins

This Bureau of Mines publication presents a method for estimating capital and operating costs associated with the exploration, mining, and processing of placer deposits. To ensure representative cost estimates, operational parameters for placering equipment and basic principles of placer mining techniques are detailed.

Jan 1, 1987

By K. L. Paciorek

The primary objective of this program was to determine the toxic fume and fire hazard of elastomeric noise abatement materials with a limited effort expended on the evaluation of specific treatments applied to mine timbers. Under the conditions employed, for a dimethyl silicone rubber, formaldehyde presented the major toxic threat; acrolein was the main toxic species for both polyester and polyether urethanes and an acrylonitrile-butadiene-styrene resin; in the case of flame-retardant styrene-butadiene rubber compositions, hydrogen chloride, and in the case of PFA-treated timber, furfural, were the major toxic compounds. Of the materials studied, the flame-retardant styrene-butadiene rubbers presented the greatest toxic hazard. The generated data have been reduced to toxic load tabulations amenable to employment for potential hazard assessment.

Jan 1, 1982

By Daniel G. DiCanio

This report describes a computer-based model for estimating the tangible costs of injuries and deaths from work-related accidents in underground coal mines. The study undertook to identify and quantify the elements of accident costs, including field visits to coal mines, insurance carriers, and public agencies. The mathematical models developed for each tangible element of accident cost are presented in Volume I of the report. A listing of the computer programs which comprise the model and instructions for using the programs are presented in Volume II. Statistical distributions of mining family characteristics, data on 95 miners killed in underground accidents, and other basic data used to develop the model are presented in Volume III. Application of the model to a data base of 9,286 accidents which occured in underground bituminous coal mines during 1974 yielded a total of $56,900,000 in tangible costs to industry, mining families, and public agencies. Loss of income to the families of miners injured or killed in these accidents accounted for 47 percent of the total.

Jan 1, 1976

By R. M. Creamer

Attempts have been made to electroplate titanium and zirconium from aqueous, nonaqueous, and fused-salt electrolytes. Metals were produced only in fused-salt electrolytes, the major product being sponge metal. All other electrolytes gave only partial reduction of the metal ions. Fused alkali borate electrolytes containing titanium salts gave titanium boride powders and coatings of poor adherence. Some of the problems encountered in the deposition of these metals and some of the aspects of titanium and zirconium chemistry involved are discussed. INTRODUCTION Titanium and zirconium are both relatively light, noncorrosive metals with both military and civilian uses. This has led to intensive investigations into the metallurgy of these metals. Both metals are high in the Electrochemical Displacement Series and are difficult to prepare in a pure state. At present they are prepared by reducing their chlorides, using magnesium. Electrolytic reductions have resulted in the preparation of fine powders or sponge of variable quality. It is believed that a good process of electroplating these metals on a baser metal would result in a very desirable product. The objective of the research summarized in this report was to investigate methods of electrodepositing these metals, with the idea of producing uniform, coherent plates. Most of the work was concentrated on titanium, the more abundant of the two metals. A system developed for titanium should be applicable to zirconium owing to their chemical similarity. Information gained from these experiments may also be applicable to the electro-winning of the metal.

Jan 1, 1954

By H. W. Gillett, E. L. Mack

Prior to 1911 the literature on melting brass by electricity consisted entirely-save for some suggestions made in patent literature but not actually worked out-of a few observations by farseeing men ' on the theoretical advantages of melting brass and other nonferrous alloys in electric furnaces. Roeber was the first to see and clearly state the possible advantages of the electric furnace in brass melting. The same factors tha.t make it desirable to manufacture special steels in the electric furnace rather than in crucibles, he declared, apply to brass as well. He pointed out the possibility of using larger melting units, of eliminating crucible cost, of readily controlling the purity of the product. and of nearly eliminating the loss of zinc. "The replacement of the • old crucible process is sure to come," he said; "perhaps it will come in two years, but it will, necessarily, in ten years .... The inevitable advance along this industrial line will have great influence in the metal world and will also provide, in large cities, a new kind of load for the central station." The years 1905 to 1910 may be termed the purely theoretical period of the development of the electric brass furnace, though the Conley furnace was tried out e:xperimenta.lly about 1910 and a few heats were made in an induction furnace. 2 In December, 1911, the American Chemical Society held a symposium on mineral wastes, at which Bassett s discussed the zinc· losses that attend making brass in fuel-fired furnaces.

Jan 1, 1922

By A. W. Deurbrouck

The separations achieved by eight conventional cyclone washers have been evaluated to determine their performance when processing intermediate size coal of 28 mesh bottom size. The dense-medium cyclones provided efficient, sharp separations in treating feeds of up to 44 percent of near-gravity material at separating specific gravities ranging from 1.42 to 1,55 (one separation of a secondary feed was made at 1.63). Complete washability analyses are shown by sizes of the composite feed to these cyclones. The magnetite losses per ton of coal processed ranged from 0.6 to 2.0 pounds; however, of the eight plants reporting losses, seven indicated magnetite losses were 1.1 pounds or less per ton of coal processed.

Jan 1, 1972

By E. R. Palowitch

Coal wasted with mine refuse represents losses in overall recovery of merchantable coal to the mine operator and a concomitant reduction in domestic reserves of available coal. Fraser, Kelley, and Graham3/ in studying the available coal in mine refuse in the Pittsburgh district of western Pennsylvania have estimated that at least 1 ton of mine refuse is produced for each 10 tons of merchantable coal and that 20 percent of this mine refuse might be recovered as salable coal by mechanical cleaning. SUMMARY This investigation dealt with the mechanical recovery of coal from wine refuse by a dense-medium washery employing pulverized mine rock as the dense medium and operating at a rate of 175 tons per hour. Two types of mint refuse were tested: Freshly mined and that .which had been mined 2 years before and piled on a waste dump.

Jan 1, 1955

By Wiliam L. Crentz

The importance of Somerset County, Pa., as a coal producer is due in large measure to the presence reserves of low-volatile bituminous coals. Although many coal beds of minable thickness are present, the important reserves are to be found in those beds underlying the Pittsburgh bed. The Kittenning beds and Freeport beds, which are responsible for the bulk of the present coal production in Somerset County and contain the largest reserves to meet future coal requirements, are usually thin and entirely free from impurities. The Pittsburgh bed, which has been such an important coal deposit in the coal areas immediately west and south of Somerset County, is of secondary importance in this county. Although generally rather friable, Somerset County coals have enjoyed wide receptability as excellent coals and to some extent have been utilized in the metallurgical market.

Jan 1, 1951

By M. H. Kline

The Cranberry magnetite deposits occur in pre-Cambrian granite-gneiss, in a belt extending from 3 miles southeast of Cranberry, N. C., to about 6 miles southwest of Magnetic City, Tenn. The belt forms a curve) elongated to the north, approximately 26 miles in length. The Bureau of Mines investigation has been confined to the eastern part of the belt, comprising the area from Fork Mountain, Avery County, N.C., to the Hcupscup Knob prospects in Carter County, Tenn. The deposits were worked at least us early as 1820. The Cranberry Iron & Coal Co. and its successors operated the Cranberry mine intermittently for about 50 years until 1930, when operations were abandoned.

Jan 1, 1948

By W. J. Boone

Experimental determinations were made of vapor-liquid equilibria data for a helium-nitrogen-methane system. A mixture composition was chosen to approximate the crude helium to be produced Or conservation that will eventually be further refined to obtain pure helium. Although there are publications of studies of the vapor-liquid equilibria of helium-nitrogen, helium-methane, and nitrogen-methane binary systems, there is little indication of work done on the ternary system of helium-nitrogen-methane. The experimental data presented in this report supplement the information available for the binary systems. The equilibrium vapor-liquid data and equilibrium vaporization coefficients are presented in tabular form. Graphs are employed to show an extensive amount of the data.

Jan 1, 1963

By Jan C. Still

The Haines-Klukwan-Porcupine subarea of the Juneau Mining District (JMD) is located in the northern portion of the JMD and consists of the land between the Alaska-British Columbia boundary, the Chilkoot Valley, Glacier Bay National Park boundary, and extending south to the Davidson Glacier and the Chilkat Peninsula and Islands (fig A-I). This area was studied as part of the larger JMD study in a cooperative effort between the Alaska Division of Geological and Geophysical Surveys (ADGGS) and the Bureau during 1985 to 1988. Prior to this, during 1984, the ADGGS and the Bureau cooperated in a study of the Porcupine mining area and during 1981 to 1983 conducted separate studies in the area. Field work was conducted by foot, boat, truck, and helicopter. Figure A-I shows the Haines-Klukwan-Porcupine sub-area and shows the areas covered by previous Bureau and ADGGS studies. PHYSIOGRAPHY AND CLIMATE The physiography of the subarea ranges from gentle to rugged. Glaciers formed the major features in the sub-area and left "U" shaped steep walled valleys and rugged mountains. The Chilkat, Chilkoot, Klehini, Tsirku, and Takhin are the major rivers in the subarea. The higher mountains are glacier clad and some valleys still harbor glaciers that reach the valley floors. Lush forests and dense brush predominate up to timberline at about the 2,000-foot elevation. Low point in the subarea is at sea level in the area around Haines while the high point is 7,434 feet at: Mount Henry Clay in the Porcupine mining area.

Jan 1, 2012

By Daniel G. DiCanio

This report describes a computer-based model for estimating the tangible costs of injuries and deaths from work-related accidents in underground coal mines. The study undertook to identify and quantify the elements of accident costs, including field visits to coal mines, insurance carriers, and public agencies. The mathematical models developed for each tangible element of accident cost are presented in Volume I of the report. A listing of the computer programs which comprise the model and instructions for using the programs are presented in Volume II. Statistical distributions of mining family characteristics, data on 95 miners killed in underground accidents, and other basic data used to develop the model are presented in Volume III. Application of the model to a data base of 9,286 accidents which occured in underground bituminous coal mines during 1974 yielded a total of $56,900,000 in tangible costs to industry, mining families, and public agencies. Loss of income to the families of miners injured or killed in these accidents accounted for 47 percent of the total.

Jan 1, 1976

By Mohan K. Wali

Soil and vegetation development were studied on abandoned mine sites near Velva in Ward County, North Dakota. The sites studied were 1, 7, 17, 30 and 45 years old since abandonment; unmined sites were also studied to provide measures of comparison. Species diversity was the highest at unmined sites (114) and lowest at the I year old site (26); sites 7, 17,30 and 45 years old had 37, 52, 43 and 68 species, respectively. Stand ordination revealed that site ages were the most important in influencing species diversity and composition. Stand-environ-mental complex ordinations encompassing 53 variables showed topographic variables to be the most important followed by site ages. Rates of nutrient accumulations were as follows: organic carbon 13.1 g m-2 yr-1; nitrogen 2.5 g m-2 yr-1; phosphorus 0.01 g m-2 yr-1; potassium 0.49 g m-2 yr-1. Carbon-nitrogen ratios showed the widest range for 1 year old sites (5-40) but 70 percent of the 45 year old sites showed values below 15 which were com-parable to the unmined mixed grass prairie sites. Species distributional diagrams are provided to show their habitat preferences which may be helpful in formulating species prescriptions for revegetation.

Jan 1, 1982

This appendix contains the list of equipment, their corresponding number and their specifications with the quotations from the vendors/ manufacturers who can supply this equipment. The listings are arranged by process plant areas.

Jan 1, 1979

By Edward L. Wilson

A general computer program is given for the linear elastic static analysis of complex structural systems. These elements have special advantages for the analysis of massive underground structures such as mine structures and above ground structures such as arch dams. New finite elements are developed which are useful in the analysis of two and three dimensional solids. Examples are given which illustrate the accuracy of the elements. A description on the use of the program and a FORTRAN IV listing are given in the Appendices.

Jan 1, 1971

By O. C. Blade

This report on the properties of burner-fuel oils produced during 1956 was issued under a cooperative agreement between the American Petroleum Institute and the Bureau of Mines, United States Department of the Interior, at the request of the Oil-Heat Institute of America and the petroleum industry. This survey is the second for this type of fuel, the first being made in 1955. 2/ The surveys are conducted to provide information on the characteristics of burner-fuel oils now manufactured for sale. They are similar in pattern to the diesel-fuel surveys, conducted since 1950, 3/ and are not intended to conflict with but rather to supplement them. The importance of fuel oil has resulted in the need for more information by the petroleum industry, manufacturers of heating appliances, and consumers regarding the types and qualities of the fuels currently being marketed. Samples of burner-fuel oil typical of their manufacture during the early part of 1956 were analyzed by the refiners in accordance with instructions from the subcommittee on fuel surveys of the Automotive Research Committee of the American Petroleum Institute, Results of the analyses were transmitted to the Bureau of Mines where the data were studied and compiled as shown in the tables of this report.

Jan 1, 1956

By William Y. Mo

This Information Circular provides a detailed background documentation of how the Bureau of Mines projects U.S. mineral demand to the year 2000. These statistical projections serve as a quantitative basis for contingency forecasting of the low, high, and probable U.S. demand for nonfuel minerals by end-use categories and are published in the Bureau of Mines Mineral Commodity Profiles and Mineral Farts and Problems series. Aluminum is used as an example in this study.

Jan 1, 1980

By M. D. Aldridge

The results of a four-year research effort aimed at developing a practical and effective electronic system for monitoring safety conditions throughout a coal mine by displaying, at a central location, remotely measured parameters are described. This document reports on the design details of the sensor packages and the data processing program used in an experimental monitoring system. The results of special ventilation monitoring experiments and several sub-system considerations are also described.

Jan 1, 1974

By D. N. Nilsen

A mathematical modeling method was developed by the Bureau of Mines for the prediction of the principal equilibrium species in the solvent extraction of copper. The use of models for predicting the amount of metal extracted can reduce the amount of experimental work required to characterize a system for purposes such as optimization studies. Models were developed for the extraction of copper from ammoniacal sulfate and carbonate solutions with commercially available extract ants commonly used by industry. Results from laboratory shakeout tests compared well with predictions of the equilibrium concentrations of copper and pH values. For example, the loading of copper onto the solvent was predicted for most cases within ±S pct of the measured values, and the pH to with-in ±O.l pH unit in sulfate systems and ±O.2 pH unit in carbonate systems. Both mechanistic and empirical extraction equations were developed from laboratory data for copper and ammonia. The empirical-based models were slightly more accurate than were the mechanistic-based mod-els. Industrial level concentrations of the aqueous and organic constituents were used in this work. Independent variables included copper concentration, ionic strength, and initial pH of the aqueous phase; extractants, diluents, and their concentration in the organic phase; and temperature.

Jan 1, 1988

By Harold J. Bennett

The purpose of this study was to develop methods for the financial evaluation of mineral deposits. This includes the selection of the best alternative mining and processing methods and production rates. This was done by performing a financial evaluation through computer simulation using sensitivity and probabilistic risk analysis. The criterion used to measure the relative advantages of these investment and operating alternatives is the discounted-cash-flow rate of return. Included is a description of the theory and methods used in the probabilistic analysis approach, which is based on the premise that the expression of a range of values in establishing an estimate for a parameter is more realistic than the choice of a single value. Numerous simulations are made using randomly selected values of the input parameters resulting in a frequency distribution of the rates of return and their relative probability of occurrence. The sensitivity analysis method is described and combined with the probabilistic analysis to interrelate mineral reserves, capital investments, operating costs, and production rates. The ability to vary these input parameters on successive runs has permitted the selection of the best alternative mining and processing methods and production rates for a given mineral deposit. For illustrative purposes the evaluation of a mineral deposit was performed using three alternative mining and processing methods at three different quantities of resources and various production rates and prices. The computer program used in this analysis was written in FORTRAN II for maximum compatability and should run without modification on most computers having BK (8,000-word) core memory, a card reader, and printer (120 characters per line).

Jan 1, 1970