Search Documents

By F. W. Wessel

This report summarizes Bureau of Mines laboratory tests of four tungsten¬-bearing materials of various grades, The test work has demonstrated that the dry reaction between sodium carbonate and scheelite is best conducted at 900° C. or a few degrees less. The sodium carbonate requirement, in addition to the stoichiometric equivalent of the scheelite, is in some inverse relationship to the grade of tungsten in the ore. Residence time and particle size exert a definite but minor control on the reaction. Pressure-digestion tests on an impure concentrate indicate the technical feasibility of extraction by this process. INTRDUCTION Over 100 years ago Oxland discovered that tungstic oxide could be removed from wolframite and converted to a soluble form by reacting the mineral with a soluble alkaline salt at elevated temperatures. He patented this discovery, and this patent 4/ since has been the basis for most tungsten extraction. Much literature exists on this process and its modifications, and the characteristics and possibilities of the reaction are quite well defined.

Jan 1, 1956

By Richard L. Rains

During this study in 1983, the U.S. Bureau of Mines examined one mine and five prospects in the Greenwater Valley Wilderness Study Area (WSA). No mineral resources were identified within the WSA. Principal mineral commodities in the WSA are gold and silver with minor lead, and zinc. Two properties have significance; sample analyses indicate the Salsberry Prospect may have gold-silver-lead-zinc resources, and the Graham Jem Mine may have gold resources. The likelihood for development is greatest at the Salsberry Prospect, although the only recorded production from the study area was from the Graham Jem Mine; in 1908 less than 1 ton of gold-bearing ore valued at $25,000 per ton was produced. Gold, silver, lead, zinc, and copper minerals in the WSA are associated with rhyolite dikes and quartz veins in Precambrian gneissic rocks, commonly concentrated in sheared zones along the dikes and veins. Although known to contain silver-lead deposits elsewhere, Precambrian Noonday Dolomite sampled inside the WSA contained no significant mineral values. Much of the WSA is covered by relatively unmineralized Tertiary and Quaternary volcanic rocks. The Bureau collected 140 rock samples at four adits, nine shafts, four trenches, and 33 prospect pits in the WSA. In 1983, 14 lone claims and one millsite within the study area were current. No patented claims, placer claims, or coal, mineral, oil and gas, or geothermal leases were in the WSA.

Jan 1, 1985

By J. H. Field

Results of studies by the Federal Bureau of Mines on a pilot-plant scale for removing hydrogen sulfide and carbonyl sulfide from gas mixtures by the hot carbonate system are given in this publication. Gases containing up to 10 pet. hydrogen sulfide and 48 grains carbonyl sulfide per 100 cu.ft. were treated. In most tests carbon dioxide also was present and was removed simultaneously with the sulfur compounds. Because the rate of absorption of hydrogen sulfide is much more rapid than that of carbon dioxide over a wide temperature range, selective removal of hydrogen sulfide occurred in the bottom section of the absorber near the point of gas entry. Hydrogen sulfide was removed to pipeline specifications with carbonate solutions by using split-stream flows in the absorber and regenerator.

Jan 1, 1960

By R. V. Ramani, C. B. Manula, A. Owili-Eger

PART 1 THE INPUT AND OUTPUT DATA AND THE MINE SCHEMATIC SHOWING THE FLOWS FROM COMPUTER SOLUTIONS FOR APPLICATION I

Jan 1, 1975

By A. T. Coumbe

This compilation of statistics covering competitive fuels consumed for heating of residential and commercial buildings is in response to numerous requests for data of this nature to show the relative changes in the demands for the different fuels in recent years. The figures presented cover the amounts of various fuels ant electric energy reported as used for heating dwellings and commercial buildings. However, the totals for gaseous fuels and electricity necessarily include amounts consumed for both cooking and lighting purposes, as these associated household uses could not be readily broken out. [ ] SOURCES OF FUEL AND POWER STATISTICS Liquid fuel: Mineral Market Reports of the Bureau of Mines covering annual Pales of fuel oil and kerosine. The fuel oil figures include grades 1 to h, reported as sold for space heating. Kerosine and grade 1 fuel oil delivered as range oil ore also included. Gaseous fuel: "Gas Facts" published by the Bureau of statistics of the American Gas Association. Thin source was used as It is believed that the data shown are representative of the actual market

Jan 1, 1953

By J. N. Greaves

Investigations were conducted by the U.S. Bureau of Mines to develop flowsheets for the recovery of tungsten and gold from four Alaskan scheelite-bearing ores. Basic gravity concentration and cyanide leach tests were performed on all samples. About 46 pct of the tungsten and 30 pct of the gold from one sample were recovered in a gravity concentrate containing 24 pet W03 (tungstic oxide) and 119 troy ounces per short ton (tr oz/st) Au. Froth flotation of the gravity concentrate resulted in separate tungsten and gold products with grades of 38 pct W03 and 2,720 tr oz/st Au and recoveries of 60 and 97 pet, respectively. Additional gold was recovered from the gravity and flotation tailings by cyanidation. Overall recoveries of tungsten and gold from this sample were 28 and 94 pet, respeetively. A flowsheet with mill design parameters was developed that consisted of (1) free gold and scheelite recovery by gravity methods and froth flotation and (2) fme-grained gold recovery by cyanide leaching of reground gravity and flotation tailings, followed by a carbon-in-pulp (CIP) circuit. Data were developed from the Bond mill work index, gold and tungsten flotation, conventional and high-rate thickening, cyanide leaching, and CIP adsorption tests.

Jan 1, 1989

By R. V. Ramani, A. S. C. Owili-eger

List of Numbers

Jan 1, 1974

By H. Tomlinson

This circular is one of a series of papers on coal mining methods and costs which being prepared by the United States Bureau of Mines for the purpose of making available to those interested in the industry a knowledge of the mining methods employed, the places here mechanical and hand loading are practiced, and coat data on the several operations pertaining to the removal of coal from the working faces and its transportation to the tipple for loading into railroad cars. Mining costs are governed by the relative efficiency of the mining method employed. The method is selected for Its adaptability to the local natural physical conditions such as the nature and thickness of the coal bed, its dip, the character of the coal, and the thickness of the overlying strata.

Jan 1, 1930

By Donelson A. Robertson

Literature was searched and cases of alleged water well damage were investigated. Occurrence of ground water in Appalachia is primarily in low yield, fractured, water table aquifers. Four test sites were chosen based on geographic and geologic diversity. Test wells were drilled at each site and base line data on water quality, static water level, and drawdown characteristics were obtained before surface mining commenced. Blast induced ground vibrations were measured at the surface by the wells at levels up to 5.44 inches per second maximum resultant particle velocity. Measurements made at the bottom wells indicated that vibrations were considerably attenuated at depths of 140 to 160 feet. No direct evidence of change in water quality or well performance was produced by blast vibrations, but removal of downslope support by excavation does cause lateral stress relief which permits the water-bearing fractures to become more open. This additional storage capacity causes the static water level to drop and for well-bore permeability to improve. Static water level recovers if sufficient recharge is available and well performance is improved.

Jan 1, 1980

By L. Keith Hudson

The purpose of this study is to provide data that demonstrates that the Alcoa flash calciner design can be used for the decomposition of AlCl3?6H2O to A1203. Heat and material valance data for calcination provides data on the partial pressure of HCl in the off-gases. Experimentally determined data for the HCl partial pressure, over solutions expected in producing alumina from clay by the hydrochloric acid process, show that HCl can be absorbed from the off-gases into process solutions to effect crystallization of AlCl3?6H2O.

Jan 1, 1979

By Richard J. Mainiero, Marcia L. Harris, James H. Rowland

In the past several years, there have been a number of blasting-related carbon monoxide migration incidents. In each case, there have been some common factors that appear to be related to carbon monoxide migration. Geology, heavy confinement of the blast, close proximity to the affected structure, and open pathways into the affected structure are just a few. Prince William County, VA is an area undergoing a boom in suburban development. In the year 2001, more than 4,050 new homes were constructed within the county.1 In the new housing development located in Bristow,VA, trench blasting was utilized to excavate proposed sewage and utility lines. On November 8, 2002, a trench blast was conducted for the installation of utility lines. Later that evening a carbon monoxide detector alarmed in a nearby house. The gas company and fire department sampled for carbon monoxide and measured 100 ppm and more than 200 ppm on the first floor and in the basement respectively. Subsequent efforts to prevent migration of CO into the nearby homes met with mixed results. The only reliable technique for protecting neighbors from CO appears to be the placement of CO monitors in the homes. The events are presented and discussed.

By Erik Bengtsson

Phenol was discovered in coal tar by Runge (1)1/ in 1834 and was isolated (2) in 1841 as pure phenol by distilling the tar, extracting with caustic soda, acidifying the extract, and fractionating the tar acids. Later, o-cresol was isolated (3) through careful fractional distillation of the tar-acid mixture. The m-and p-cresols distilled within a boiling range of about 1.50 c. and had to be separated by other means. Raschig (4) fractionated the tar-acid mixture to obtain pure o-cresol, sulfonated the mixture of m-and p-cresols, and treated the cresol-sulfonic acids with superheated steam at 1200 to 1300 c. to hydrolyze the m-cresol sulfonic acid, the p-isomer was not affected at that temperature. He also attempted to make use of the different crystallizabilities of the m-and p-cresol sulfonic acids (5). When treated with sodium bisulfate and sodium pyro-sulfate at 100° to 110° C. or with sulfuric acid (90/0) at 20° C., only the m-cresol was sulfonated (6). Hoffman-La Roche (7) treated the meta-para mixture with concentrated sulfuric acid at 40° to 100° C., when m-cresol and part of the p-cresol was sulfonated, and precipitated the m-cresol sulfonic add by diluting with water. The same sort of separation may be carried out by means of 80 percent sulfuric acid at 35° C. and 35 mm pressure (8).

Jan 1, 1950

By L. R. Burdick

Sulfur compounds have long been recognized as damaging pollutants of the air. A number of investigations have been made to determine the amount of such compounds existing in the air of various cities; moreover, some study has been given to the conditions affecting the concentrations. This paper summarizes published investigation and includes a bibliography on the subject. The methods of obtaining data have differed to the type of sampling, analysis procedure, hour of sampling, number of locations, and number of determinations made. Sampling methods include both the continuous type, covering a day or a number of days, and what can considered the ?snap? type, covering very short periods. Continuous sampling has, given data representing the average concentration at the location chosen but no information regarding variations from hour to hour, are none that might be said to represent the average for a city. The snap-sampling method, while not giving a true average for any one location or area, has in some instances made available date regarding variations of concentration during different hours of the day and at various locations or zones within the area chosen. Although the sulfur compounds in the air nay include sulfur dioxide, sulfur trioxide, hydrogen sulfide, and organic compounds of sulfur, most investigators report on the basis of sulfur dioxide. This gas unites with moisture to form sulfurous acid.

Jan 1, 1939

By J. F. Barkley

At the request of several Federal agencies, tests were conducted on a relatively recent type of anthracite -burning equipment named the Anthratube. This device, rated at 130,000 B.t .u. per hour, was designed to burn Pea-size anthracite automatically for steam or hot-water house heating and for domes-tic hot -water supply. ACKNOWLEDGMENTS The helpful cooperation of the Anthracite Institute and the manufacturers of the equipment, Axeman-Anderson Co., Williamsport, Pa., is gratefully acknowledged.

Jan 1, 1953

By G. E. McClelland

The Bureau of Mines investigated chemical methods for producing high- purity gold from precious-metal-bearing zinc precipitates and steel wool cathodes. Precious-metal-bearing zinc precipitates and steel wool cathodes are unrefined products from conventional cyanidation and heap leaching-cyanidation operations. The zinc precipitates contained 14,40 pct Au and 0.35 pct Ag. The precious-metal-bearing steel wool cathodes contained 20.65 pct Au and 4.84 pct Ag. The precipitates and cathodes were treated with dilute acid to solubilize the silver and/or base metals. The gold-bearing residue was leached in dilute aqua reqia to solubilize the gold. High-purity gold was precipitated from the aqua regia solution with oxalic acid, sulfurous acid, sodium bisulfite, and gaseous sulfur dioxide. The leaching-precipitation experiments recovered 99.9 pct of the gold. The gold precipitates ranged in fineness from 997 to 999 fine. The chemical refining method provides a viable technique for the smaller operator to produce high-purity gold without using pyrometallurgical refining methods.

Jan 1, 1985

By Sol Weller

The Fischer-Tropsch synthesis consists of the formation of long-chain hydrocarbons by passage of carbon monoxide-hydrogen mixtures over metal catalysts, usually based on iron, cobalt, nickel, or ruthenium, at temperatures in the range 180°-300° C., and at pressures of 1-15 atmospheres. Although the reaction has been known and studied for more than 20 years, the mechanism by which it occurs is still poorly understood. One approach to understanding is to consider the effect upon the course of the synthesis of variations in each of the important operating variables. Consideration of the experimental data pertaining to these variables may suggest an over-all picture describing the synthesis - a picture which, in turn, would have to be consistent with all the known facts. The first part of this paper will be concerned with such a consideration of operating variables; the second portion will discuss recent work pertaining to the role of metal carbides as intermediates in the synthesis.

Jan 1, 1949

By Fremont T. Johnson

Credited with production of more than 164,000 flasks Of quicksilver from 1876 to 1944, the Oat Hill mine has ranked third in output in the United States. During World War II, when the demand for mercury was high, this property was selected for diamond drill with the purpose of increasing ore reserves so that production could be maintained or, if necessary, increased. Although the existence of marginal-grade ore (fill material) left in the stapes and possibly of virgin ore of good grade had suspected in certain parts of the Oat Hill mine, no factual information to tonnage, grade, or location was available. In close cooperation with the Federal Geological Survey, the Bureau of Mines studied old records and the few available incomplete maps. Diamond drilling began in November 1943 and was completed in December 1944. Twenty-eight holes aggregating 8,121 feet were drilled, in only parts of the promising areas disclosed by the study of the data available. Detailed data on the work done by the Bureau as well as a brief history of the property and some operating details are described in this report.

Jan 1, 1949

By L. S. Breckon

This paper describes the methods and equipment used by the Utah Copper Co. in constructing a vehicular tunnel at Bingham Canyon, Utah, Completion and use of this tunnel for vehicular and pedestrian traffic permitted abandonment of the long-used county highway connecting Bingham and Copperfield. Expanding- operations of the Utah Copper open-cut mine, necessitated construction of a vehicular route away from the ore body. The site Of the tunnel is well beyond ultimate nit slopes and future mining operations. The tunnel not only diverts vehicular and pedestrian traffic is but also carrier, creek water, copper water, sewage, pipe lines, and. power and telephone cables between the two communities. The dimensions of the tunnel permit one-way traffic only. Traffic-control lights have been installed. Owing to the possibility of accumulation of carbon monoxide gas from automobile exhausts, automatic gas detectors has been installed at various stations. These detectors control the operation of a large exhaust fan situated at the upper portal of the tunnel.

Jan 1, 1940

By A. S. Swanson

In view of the necessity or increasing production of metallurgical fluorspar to satisfy wartime demands, 0, M. Bishop, former district engineer of the Bureau of Mines, L. W. Carrier and. J. S. Williams, senior geologist of the Federal Geological Survey, and E. H. Dawson, mining engineer of the War Production Board made a joint survey of the Illinois-Kentucky fluorite district in July 1942 to determine what steps should be taken to increase production. As part of their recommendations, a program for exploring the idle Klondike mine in Livingston County, Ky., was outlined. All the ore produced at the Klondike mine was mined above the 325-foot level, where some tonnage remains. Factors that influenced selection of the Klondike mine for exploration were favorable geological conditions, the state of mine development and the availability of pumping equipment and some usable mine and mill equipment. In December 1942, the Metals Reserve Co. leased the Klondike mine from the Salem Fluorspar Co.

Jan 1, 1949

By Potts J. D.

Installation of a horizontal air-blocking shelf around the inside perimeter of the surface mining drill deck shroud is proposed to improve dust capture. Without the use of this shelf, a strong Coand? effect airflow pattern results in dust leakage to the environment, especially at the shroud-to-ground interface. Bailing air exits the drill hole and travels along the drill steel to the underside of the table, where it fans out across the bottom of the drill table and continues down the sides of the shroud. This dust-laden bailing air then strikes the ground and fans out under gaps between the shroud and the ground. The proposed shelf prevents dust-laden air from striking the ground by redirecting it toward the center of the enclosure, where it can be captured. Laboratory tests demonstrated that the shelf reduced dust levels outside of the shroud by 81% under operating conditions consisting of a 1.9:1 collector-to-bailing-airflow ratio and a 51-mm (2-in.) gap between the shroud and ground. The shelf was 152-mm (6-in.) wide and was located at a height equal to 2/3 the distance measured from the bottom of the shroud to the bottom of the drill table. The air-blocking shelf was also capable of overcoming the adverse impact of vertical leakage along the shroud seams as long as this leakage was confined to an area below the horizontal plane defined by the shelf location.

Jan 1, 2008