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By Walter I. Enderlin

To economically extract ore from great depths in the earth while sustaining an acceptable working environment will require the development of new technology and equipment, involving large capital expenditures. Moreover, careful analysis and advance planning will be required. But, the literature is lacking in data pertaining; to the thermal properties of various host rocks and to quantities of heat generated by various underground heat sources. This types, of data is required to forecast nine heat loads during advanced planning and design. This thesis sets forth a practical method for evaluating underground sources of heat in deep mines and provides an improved information base. Moreover, seven topics for further research are recommended. The heat sources considered are: wall-rock, ground water, adiabatic compression, equipment, service lines, blasting, metabolism, curing of cement, and oxidation of sulfides and timber. Seven deep metal mines with high production rates and high heat loads were visited to obtain data necessary to assess their thermal environments. Mine records were examined, wall-roc:, temperatures were measured and a survey of the mine ventilating air and mine drainage was performed. Also, the thermal conductivity of wet and dry specimens of the host rock were measured in the laboratory. Data analysis disclosed that rock heat and adiabatic compression account for stout 60 per cent of the mine heat load at depth. Equipment currently contributes approximately 20 per cent; however, to offset increasing costs with depth, increased mechanization is anticipated. The treat from ground water averages 19 per cent and the contribution from blasting, metabolism and cement is negligible. Also, approximately [0] per cent of the increase in the enthalpy of the ventilation air is in the form of latent heat. Moisture, however, did not significantly affect the thermal conductivity of the rock specimens measured in the laboratory. Also, from the data, it is evident that a negative correlation exists between the thermal conductivity of the host rocks and the per cent of the heat load derived from the wail-rock. Furthemore, steady state heat flow renditions may be assumed in airways where there has been no major changes in the ventilation system for a period of two years or more. Under these conditions, the author found it more convenient and reliable to compute heat influx using the steady state equation for heat flow into a cylinder, rather than Carrier's method for transient heat flow, which is so often used.

Jan 1, 1973

By R. A. Busch

Sludge ponds of fine coal, fine soil, and water created behind large piles of coarse coal waste can present hazardous conditions; this is a Bureau of Mines report of the subsurface physical property data developed on the fine coal waste materials that make up the core areas of two typical coal waste impoundments. These data will help define more completely the engineering properties of this problem area of the structures. Additional calorific, chemical, and mineralogical data were obtained on the coal waste materials to determine possible uses or development of byproducts. The possibility of extracting alumina from coal ash was also investigated.

Jan 1, 1975

By John A. Organiscak

The Bureau of Mines conducted a survey of eight shearer longwall operations to identify factors that affect respirable dust generation from longwall roof supports. The longwalls surveyed were in coal seams located in different geographic regions of the United States. Data were collected on mining (geologic) conditions, support design, operational characteristics, and amount of respirable dust generated from roof supports. Analysis indicated that mining conditions are the main factors that affect the generation of dust during roof support movement. Both roof strength and depth of cover above the coal seam showed relationships with the amount of support dust generated. Several practices are currently employed to effectively control roof support dust; however, some of these controls are limited. More research and development is needed to improve dust control technology for longwall roof supports.

Jan 1, 1985

By A. J. Martin

The Tri-State, or Joplin, zinc and lead mining district in south- western Missouri and adjoining, parts of Kansas and Oklahoma is one of the great mining districts of the world. It is in flat-lying or gently rolling agricultural country near industrial centers and coal, oil, and gas fields. The nearly horizontally, lying bedded rocks in which the ore bodies are found were originally limestone but are now largely chert containing minor percent- ages of dolomite and other minerals. The ore occurs in nearly vertical fis- sure zones, large and small, and in blanket (sheet-ground) deposits. The mining depth ranges from surface diggings to $50 feet. The average tenor of the ore mined, in recent years is much lower than that of ore produced in other large zinc and lead districts of the United States. Mining and mill- ing costs are low because of the shallowness of mining, amenability of ores to concentration, efficiency resulting from long experience of management and labor, and other factors. The operators comprise many small and medium-size producing companies and partnerships, as well as individuals and a few larger producers. About 7,000 men are employed in the mines and mills during normal industrial activity. The concentrates produced are sold f.o.b. the mill bins to local representatives of smelting companies at prices quoted on the Joplin market. The productive life of the district began with the discovery of lead near Joplin in 1848, but output was not large until after mining for zinc began near Granby in 1871. In most of the intervening years through 1945 the district produced more zinc than any other field, and it generally ranked third or fourth in the United States in lead production. Figures compiled from sources given later in this paper show a total output for the district from the beginning through 1945 of 20,755,020 tons of zinc concentrates and 3,334,057 tons of lead concentrates valued altogether at $1,110,058,581 in the mill bins. The output, in terms of recoverable metals, was 10,609,408 tons of zinc and 2,529,121 tons of lead, valued in all, at the average yearly market prices of the metals, at $1,691,282,419. During the 39 years (1907-1945) for which complete figures are available, the annual output of the district fluctuated from 23 to 66 percent of the total United States mine output of zinc and from 5 to 18 percent of the total lead; the averages for the period were 40 percent for zinc and 11 percent for lead. peak yearly production was attained in 1926, with an output of 423,800 tons of recoverable zinc and 102;117 tons of lead. Since that yoar the production rate has trended downward, accentuated at first by the depression in the thirties and later ameliorated somewhat under the stimulus of heavy demand and higher metal prices during World War II; the output in 1945 was 139,274 tons of recovorablo zinc and 23,556 tons of load. The above figures show the groat contribution made by the Tri-State district in the past toward the country's supplies of primary zinc and lead, cspecially zinc. However, the district's production is expected to decline both in quantity and in proportion of total United States mine output unless important discoveries are made. Ore exposed in mine workings and extensive exploratory drilling done in recent years within and without the productive The

Nov 1, 1946

By Galen G. Waddell

Dilation and contraction of the rock surrounding horizontal access open-ings of a deep mine were analyzed during stope advance to determine what type of measurements, made with relatively inexpensive instrumentation, would best reflect the rock behavior. A variety of instruments, mostly mechanical extensometers, were used. Detailed descriptions are given of Down-the-hole extensometers, floating rockbolt clusters, transit surveys, and other instruments and measuring techniques. Although all of the radial-deformation-rate graphs illustrated useful rock behavior data, the most informative graphs were compiled from data procured with the radial extensometers that penetrated, to various depths, the rock around the access openings. An analysis is given of measurement data on the rock around lateral drifts and across and adjacent to the nearly vertical vein of the Star mine, Burke, Idaho. Several useful relationships were found between the rock deformation rate and the stoping process. Information was produced on the elastic state of rock around an underground opening, effectiveness of stope support, rheology of rock, zone of influence around stopes, effectiveness of rockbolts, axis of maximum strain in a plane perpendicular to the long axis of the lateral, and other phenomena. This information could be of particular value in determining location, design, and support of underground openings.

Jan 1, 1966

Develop a user-friendly, personal computer-based numerical modeling program that performs structural analyses of underground tabular deposits, making these readily available to the mining industry. Background When ore is extracted from an underground mine, the overburden weight is redistributed to unmined areas, recompacted gob zones, and artificial structures such as packwalls and/or cribs. This redistribution of stresses continually changes throughout the mining cycle and can be especially complicated when multiple-seam mining is involved. Numerical mine structural analysis methods provide a way of calculating the redistribution of overburden stresses and the resulting loading for any given area of an underground mine, thus enabling engineers to design safer and more productive mines. In 1973 Crouch and Fairhurst developed a mine structural analysis computer program called MINSIM. This computer program was based on the three-dimensional displacement-discontinuity approach, a subvariation of the boundary-element method. In 1979 Sinha expanded MINSIM's capability to provide an analysis of parallel multiple seams. Sinha called his program MULSIM. During 1984 and 1985, the Bureau of Mines upgraded and completely restructured MULSIM into what is now called MULSIM/BM.

Jan 1, 1990

By D. Harrington

Every few weeks United States newspapers of 25 or 30 years age ran scare-heads telling of some mine disaster, which was a first-page attraction for a day or two and then was forgotton until another disaster occurred a few weeks later. Interspersed with these disasters were the so-called sniping mine accidents, causing the death of one or two mine workers. The summation of all types of mine fatalities usually exceeded 3,000 a year. In the period 1906-10, inclusive, there wore 84 major explosion disasters (or about 17 per year) in united States coal mines; the fatalities resulting from those disasters numbered 2,388 for the 5-year period. These frightful catastrophies helped to cause the total number of fatalities in our coal mines for the 5 years (including the fatalities from major explosions) to reach the enormous total of 13,288, an average of 2,658 per year. In addition, some hundreds of other typos of mining accidents swelled the annual fatality list to upwards of 3,000. This admittedly deplorable condition created so much Nation-wide comment that Congress was impressed with the necessity of having something done by the Federal Government with a view to trying to halt at least sonic of the excessive loss of life in our mines; in consequence, the Bureau of Mines was created and began to function in July 1910.

Jan 1, 1935

By Raymond Derzay

This publication is intended to be of value to the mineral industry in establishing and maintaining effective programs for preventing noise-induced hearing loss. Factors involved in this loss and the need for and the requirements of an effective hearing conservation program are discussed. The legal and legislative history of compensation for hearing loss is briefly reviewed. A review of statutes is not attempted since several States have recently modified) or are in the process of modifying their laws regarding permissible noise exposures) required hearing protection) and/or compensation for hearing loss. A review of other aspects of the problem of industrial noise in terms of medical, physiological) and psychological frames of reference is included. A hearing conservation program is described in detail. Appendixes detailing the names and addresses of a few equipment suppliers are included. References are provided for those who may wish to delve more deeply into the medical, technical, and scientific considerations of noise and its effect on man.

Jan 1, 1972

By G. W. Elger

This report describes pilot-plant studies and an economic evaluation of a process developed by the Federal Bureau of Mines, Albany Metallurgy Research Center, to produce synthetic rutile from a rock-type ilmenite concentrate. In this process, ilmenite blended with coke and lime is smelted in an electric arc furnace to separate most of the iron as salable pig iron and to form a titania-enriched slag of low iron content, which is treated with oxygen and titanium pyrophosphate. The titanium oxides are converted to crystalline rutile; the phosphate glass contains most of the associated impurities. The treated slag is ground and leached with sulfuric acid to liberate rutile crystals, which are concentrated by physical methods. In pilot testing conducted to obtain data for a cost estimation, a synthesized product containing about 88 wt-pct TiO2 and less than 2 pct FeO was extracted from a rock-type ilmenite concentrate containing about 45 wt-pct TiO2. The estimated fixed capital cost (on a mid-1975 basis) of a plant producing 500 tpd of synthetic rutile is $28,290,100. Based on 330 operating days per year, the estimated operating cost for this process is $351 per ton of synthetic rutile. The estimated selling price of synthetic rutile made from rock-type ilmenite is $344 per ton, based on a credit of $160 per ton of pig iron and a 20 pct interest rate of return on investment after taxes.

Jan 1, 1976

By James S. Browning

The Bureau of Mines conducted laboratory batch and small-scale continuous selective flotation tests of barite-fluorspar ores from two deposits near Marion, Ky., to determine the technical feasibility of recovering commercial grade fluorspar and barite concentrates. The lignin sulfonate-sodium fluoride method of floating the fluorspar successfully produced acid-grade fluorspar concentrates. Flotation of the barite from the fluorspar tailing using petroleum sulfonate collector yielded concentrates suitable for use in compounding oil-well drilling mud. The fluorspar and barite recoveries were about 82 and 85 percent, respectively.

Jan 1, 1963

By Charles B. Kenahan

A summary of Bureau of Mines research on utilization and disposal of solid wastes is presented, accompanied by an extensive bibliography of related publications. The Bureau's Solid Waste and Materials Recycling Program is directed toward four main areas of research, development, and demonstration: (1) extraction of mineral, metal, and energy values from urban refuse; (2) upgrading and recycling of automotive and related ferrous and nonferrous scrap; (3) utilization and stabilization of mine, mill, and smelter wastes; and (4) recovery and reuse of values from industrial waste products. A contract and grant program that supplements the in-house research and aids in the training of manpower in management of mineral-, metal-, and energy -based solid wastes is also discussed. This publication is an updating of Bureau of Mines Information Circular 8460 issued March 1970.

Jan 1, 1971

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski County, Ark., has been given in Report of Investigations 4251. The factual data obtained during the project are reported in a series of Reports of Investigations beginning with No. 4251, of which this is the eighth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate half-township map. The description of each half township is no followed by a description of each deposit developed in that half township. The 14 half township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project, except the deep holes drilled to test the geophysical anomalies. The locations at those holes show on figure 13 in volume I. The descriptions of the deposits developed are followed by complete detailed logs at the drill holes. Many at the widely spaced exploratory holes did not discover bauxite of minable thickness and gra.de. The pertinent information obtained from the widely spaced exploratory drill holes has been summarized and tabulated, and a table for each halt township is given with the discussion covering that area.

Jan 1, 1948

By James H. Scott

Well-logging techniques that have been used to evaluate various types of mineral deposits are discussed briefly, and many pertinent references are cited. Information is categorized by mineral commodity to make it easy to determine what logging techniques have been used for evaluating specific metals and nonmetals. Part 1 discusses logging techniques applied to deposits of the following metals: aluminum, antimony, beryllium, boron, copper, iron, lead and zinc, maganese, mercury, nickel, silver and gold, tin, tungsten, and uranium. Part 2 covers the following nonmetals: coal, evaporites, fluorspar, oil shale, rock salt, and sulfur. Separate bibliographies are given for English and foreign language references.

Jan 1, 1974

By L. A. Neumeier

A refinement of the tungsten-cobalt phase diagram is presented for compositions to 85 at. pct cobalt and for temperatures to the solidus. Preparation of alloys by powder metallurgy methods is described, and the results of studies made by a combination of techniques involving microscopy, X-ray diffraction, thermal analysis, and dilatometry are discussed. The existence of u-W6Co7 is confirmed (rhombohedral D85 structure). The W6Co7 phase forms periectically at 1,685'115° C by reaction of liquid with primary W; the peritectic melt is at 71 at. pct cobalt. The homogeneity range of u-W6Co7 extends to both sides of the ideal stoichiometric ratio, through a compositional range of about 5 at. pct. The compositional limits for u-W6Co7 vary slightly below 1,471°±5° C, the temperature of the eutectic reaction forming u-W6Co7 plus a. The eutectic composition is at 79 at, pct cobalt. The existence of WCo3 is confirmed (hexagonal D019 structure). WCo3 forms peritectoidally at 1,093°±5° C by reaction between a and u-W6Co7 and exists over a narrow homogeneity range of 0.5 to 0.6 at. pct. The solid solubility of cobalt in tungsten is low (maximum 0,9 at, pct cobalt) and results in contraction of the tungsten lattice. Tungsten is extensively soluble in a-Co at higher temperatures; the a-Co lattice is expanded by the presence of tungsten in solid solution. There was no indication of the formation of a o-phase nor of any intermediate phases other than WeCo7 and WCo3. The WeCo7 and WCo3 phases are compared with similar phases in other systems.

Jan 1, 1967

By C. H. Riggs

This report describes the development, oil recovery, and potentialities of productive formations in the Hall-Gurney field, Russell County, Kans. It is presented as part of a general program to aid and promote increased recovery from petroleum reservoirs. The report is based on studies of well logs, drill cuttings, and oil-and water-production histories of individual wells and leases. The geological interpretations follow closely those in published literature with only slight local modifications. Oil and water analyses, made at a Bureau of Mines research center, were supplemented by many analyses obtained from oil-producing and service companies. The Hall-Gurney field, in south central Russell County, Kans., (fig. 1) was discovered in 1931 but was not developed extensively until 1941. By 1960 the rate of oil production from the field had declined to the extent that many wells were abandoned. In some areas natural productive forces have effected good recovery. However, in other areas inefficient waterflooding, both natural and accidental, has adversely affected recovery potentialities.

Jan 1, 1963

By James R. Kerr

Although metallurgical benefits of processing metals in a vacuum or reduced atmosphere have been realized for a hundred years, the problem of creating a vacuum in the range from 10-0 to 10-4 mm. of mercury in a moderately sized furnace chamber has been difficult to solve. The demand for these and lower pressures, with the advent of World War II, for separating the fission-able uranium isotope from its stable twin by the electromagnetic process, gave impetus to developing pumps capable of delivering extremely low pressures. With the release of data by the Atomic Energy Commission on methods of securing high vacuum in large equipment, steel companies took the initiative, and the growth of the vacuum-melting industry was assured. Vacuum-induction melting of steel in the United States began on a small scale in early 1945 and in 10 years grew to 60,000 pounds per month or 720,000 pounds per year. The years following 1954 showed tremendous expansion, culminating in 1958 in a capacity of more than 36 million pounds.

Jan 1, 1962

By Robert J. Timkp, James D. Noll, Peter Hall, Robert Haney, Linda McWilliams

Diesel particulate matter (D PM) samples from underground metal/nonmetal mines are collected on quartz fiber filters and measured for carbon content using National Institute for Occupational Safety and Health Method 5040. If size-selective samplers are not used to collect D PM in the presence of car-bonaceous ore dust, both the ore dust and D PM will collect on the quartz filters, causing the carbon attributed to D PM to be artificially high. Because the D PM particle size is much smaller than that of mechanically generated mine dust aerosols, it can be separated from the larger mine dust aerosol by a single-stageimpacto1: The SKC D PM cassette is a single-stage impactor designed to collect only D PM aerosols in the presence of carbonaceous mine ore aerosols, which are commonly found in underground nonmetal mines. Howeve1: there is limited data on how efficiently the SKC D PM cassette can collect D PM in the presence of ore dust. In this study we investigated the ability of the SKC D PM cassette to collect D PM while segregating ore dust from the sample. We found that the SKC D PM cassette accurately collected D PM. In the presence of carbon-based ore aerosols having an average concentration of 8 mg/m3, no ore dust was detected on SKC D PM cassette filters. We did discover a problem: the surface areas of the D PM deposition SKC D PM cassettes, manufactured prior to August 2002were inconsistent. To correct this problem, SKC modified the cassette. The new cassette produced, with 99% confidence, a range of D PM deposit areas between 8.05 and 8.28 cm2, a difference of less than 3%.

By George T. Motock

In Germany the extraction of lithium and its salts has been handled mainly by units of the two major concerns - Metallgesellschaft A, G. and Deutsche Gold und Silber Scheide Anstalt, both with headquarters in Frankfurt. Zinnwaldite, which belongs to the mica group, is the major source of the lithium-containing raw material in Germany. Lepidolite and amblygonite also are used when available, but they are imported, as there are no major deposits of these two minerals in Germany.

Jan 1, 1946

By W. C. McBee

Technology for the preparation of densifiable sulfur concrete (sulfapave) materials has been devised by the Bureau of Mines. The materials are intended as new construction materials for use in corrosive areas where conventional materials fail. A series of modified sulfur cements were developed, which can be used in combination with dense-graded aggregates to prepare sulfapave materials with excellent corrosion-resistant properties. The materials can be mixed, laid, and compacted into place with conventional hot-mix asphalt pavi.ng equipment. Mixture designs utilizing 5-to 30-pct-modified sulfur cements and dense-graded aggregates gave material properties ranging from rigid to flexible. Laboratory corrosion tests in sulfuric acid showed no material loss or deterioration of physical properties over a 1-year test period in concentrations ranging from 0 to 60 pct at ambient temperatures. Preliminary results on field testing the materials for durability to weathering, corrosion, and traffic have been excellent, with no evidence of failure in the materials.

Jan 1, 1985

By Anthony M. Opyrchal

This Bureau of Mines study assesses the economic significance of the Florida phosphate industry to selected counties in Florida, the State of Florida, and the Nation: it also includes a brief survey of the industry's international impact. Based on forecasts of Florida phosphate production in 1981, and using constant 1977 dollars. estimates are given for 1981 for regional and national output the value of this output, income, and employment created by the phosphate industry in Florida, Federal, Stale, and county tax revenues generated by the State's phosphate industry are also estimated for 1981. The concentrated impact of the phosphate industry on certain areas of Florida and on the State?s regional industries is examined using economic base analysis complimented by an industrial complex approach. The industry's impact at the Stare and national levels is examined through input- output analysis. In addition, an attempt to forecast for 1990 the effects of constraints on phosphate rock mining as a result of economic conditions and other factors is included as an appendix to the report. Also discussed is the phosphate industry's importance to the U.S. balance of trade: U.S. agricultural production. Including forward linkages; the U.S. sulfur industry; and the phosphate industry's importance to the production of fluorine and uranium by- products from fertilizer manufacturing.

Jan 1, 1981