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By Arcy R., D&apos George

The Bureau of Mines has developed, on a laboratory scale, a superior Eluex-type circuit for eluting and recovering uranium from ion exchange resins. The improved circuit differs from conventional Eluex practice in that a stage of uranium solvent extraction is coupled with each stage of resin elution rather than the elution and solvent extraction operations being conducted separately. The new system reduces the number of stages, retention time, and resin inventory in the elution circuit to one-fourth or one-fifth that in existing circuits. The system is applicable to both resin-in-pulp and moving-bed-type ion exchange uranium recovery circuits.

Jan 1, 1969

By Ronald A. Vary

This paper is one of a series prepared by the United States Bureau of Mines dealing with milling methods and costs. In view of the current revival of interest in gold mining, information dealing with practices and costs in the development of gold properties is apropos. Milling practice at a small gold property in the prospect stage is described where, with a small outlay for plant and equipment, development has been carried on for about 20 months on the proceeds of the mill operation with little additional expenditure. The paper shows about what may be expected as to costs at a small property operated under northern climatic conditions and with rigid economy throughout the plant.

Jan 1, 1931

By S. P. Kinney

[The blast-furnace operator is often confronted with the problem of determining the size of the materials which are used in the furnace burden. The statement is heard that the coke is larger or smaller or that certain ore is finer than that previously used. A screen analysis of the materials used gives a measure of the different sizes of materials in an aggregate. When one is fine and the other is coarse, the difference is obvious; but when the materials are of similar sire, it is more difficult to estimate the degree of finances or coarseness. In considering raw materials it would be desirable to be able to judge the size of the radio ideal materials entering the furnace and the burden as a whole, by one representative value, such as the average size of particle. Previous work by Perrott and Kinney3 developed a method for measuring the average size of particle in a mass of finely ground materials, and an attempt will be made to apply this method to the materials included in the blast-furnace charge and to the entire burden.]

Jan 1, 1930

By N. A. Eilertsen

This report describes field investigations conducted in 1953 of two occurrences of manganese and a separate magnetic anomaly in the Southern manganese district of Aroostook County, vicinity of Houlton, Maine -the Pierce deposits, in Hammond Plantation Township; the Burnham anomaly, also in Hammond Plantation; and the Nickerson-Farm prospect in Hodgdon Township. The manganese occurs in a thinly laminated sedimentary rock containing manganiferous carbonate interlayered with fine-grained metamorphosed sediment, rich in chlorite or hematite. The surrounding rocks are mostly dark gray-green slates. Samples composited for metallurgical testing from the Pierce deposits and the Nickerson-Farm prospect assayed 9.0 to 12.3 percent of manganese. More than 90 percent of the manganese could be extracted with sulfuric acid, but in most instances 30 to 40 percent of the iron was also extracted. Leaching tests indicated that, after being reduced in a hydrogen stmosphere at 600° C., about 85 percent of the manganese could be selectively extracted by a solution of ammonia-ammonium carbonate with iron extraction of only 14 percent.

Jan 1, 1958

By R. Hogg, J. M. Mutmansky, E. Kaya

"Characterization of the size, shape, chemical composition, and mineralogical content of mine airborne dusts generally requires a larger mass of dust particles than is typically collected using traditional sampling devices. In this paper, the general design of a passive dust collector is described and the field results are presented. The collector was constructed of galvanized sheet metal duct with a resin-coated honeycomb to provide an elutriation-type system for particle collection. Several versions of the collector were used in the field portions of the research.The dust samples collected from underground coal mines were found to possess angular particle shapes, relatively consistent size distributions, and elemental compositions that showed relatively little variation, at least for the more prevalent elements. In addition, the distributions of particles sizes obtained from the passive dust collector appear to be similar to those of samples collected at the same time in a conventional personal sampler except that the passive device seems to collect a larger quantity of coarse, nonrespirable particles. Conclusions on the suitability of this dust collector for collecting characterization samples are presented. In addition, the potential for using such a dust collection system for supplying dusts for biomedical research is discussed.INTRODUCTIONRecently, a considerable amount of research effort has been directed toward better understanding of the characteristics of the coal dust generated during the mining process. It is generally believed that dust characteristics play a significant role in the development of Coal Workers' Pneumoconiosis (CWP). In order to effectively protect coal workers from coal dust, it is important to understand the properties of dust, the mechanisms of generation and dust-lung reaction. Conducting research on dust characterization, dust control and the biomedical aspects of dust toxicology generally requires a large sample of airborne coal dust. Unfortunately, current dust sampling instruments are not able to meet this demand because only a few milligrams of dust are collected."

Nov 1, 1995

By T. OnIin, F. F. ApIan

"A study has been made of the surface properties of coals of differing ranks, in their natural state and as modified by the addition of collectors. The evaluation of their surface properties has been done by captive bubble contact angles, water and methylene iodide sessile drop contact angles, zeta potential, point-of-zero charge (PZC) shift, and flotation. .changes in the hydrophobicity of coal is a function of both the rank of the coal and the collecting reagent.INTRODUCTIONThe chemical and physical properties of a raw coal will determine its response to a given beneficiation process. .For such processes as flotation, filtration, flocculation, dispersion, handling, dust supression and agglomeration, however, it is also necessary to consider the surface properties of the coal and mineral matter constitutents of the raw coal. In the case of a specific particle to be floated, it is also necessary to consider the properties of the coal as modified by the addition of some reagent designed to modify (usually increase) the hydrophobicity of the coal surface. General properties of the coal have been well summarized by Van Krevelen (1) and Elliott (2), while the data for the surface properties of coal are much more scattered in the literature (see, e.g.: Parekh and Aplan (3), Gutierrez-Rodrigues et al. (4), Aplan (5), Arnold and Aplan (6), Hogg and Chander (7) and Rosenbaum and Fuerstenau (8)). While a knowledge of the inherent surface properties of a sample are important, of much greater practical significance are the properties of the particle in the presence of a reagent, such as a collector, designed to enhance the hydrophobicity of the particle. This study will focus on the surface properties of coals of various ranks in the presence of a variety of collectors."

Jan 1, 1989

By Michael S. Miller

In 1987, 1988 and 1989, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the Sperry Creek Wilderness Study Area (OR-003-035; 5,600 acres) and the Gold Creek Wilderness Study Area (OR-003-033; 13,600 acres), plus an additional area (OR-003-033; 2,180 acres) adjacent to the Gold Creek Wilderness Study Area. The wilderness study areas and the addition are south of the Malheur River and are about 20 miles east of Juntura, Oregon. The wilderness study areas and the addition are underlain by volcanic rocks, predominantly basalt and rhyolite flows, breccias, and welded ash-flow tuffs. Lacustrine deposits containing diatomites occur mainly at the east side of the Gold Creek Wilderness Study Area and addition. Alluvium lies along the Malheur River, in terraces and fans south of the Malheur River, and along the floors of some creeks. Shear zones and faults have offset the rocks and provided channels for eruption of volcanic rocks and epithermal mineralization by hot springs.

Jan 1, 1989

By Thomas V. Falkie, R. Venkataramani

Table

Jan 1, 1972

By Philip E. Sanker

The Bureau of Mines conducted small-scale batch and semicontinuous tests on the reduction of zinc sulfide with iron according to the reaction ZnS + Fe ? FeS + Zn to determine reaction kinetics in the temperature range 1,000° to 1,400° C and to investigate the potential use of a scrap iron reductant. Batch tests indicated that a temperature of at least 1,300° C with a 1:1 mole ratio of Fe to ZnS is needed for good zinc recovery. Semicontinuous tests were conducted, using four zinc concentrate samples, containing various percentages of copper, cadmium, and lead, which were reacted with iron and iron contaminated with iron oxide and tin in an externally heated graphite furnace. Analysis of the zinc metal and FeS matte reaction products showed cadmium to be entirely in the zinc metal, copper to be in the FeS matte, and lead to be about 60 pct in the zinc metal and 40 pct in the matte. Tin reported to the matte, and none was detected above the O.OS-pct level in the zinc. Sulfur dioxide was not detected in the offgas when up to 20 pct of the iron was replaced by Fe203.

Jan 1, 1976

By A. L. Engel

This report is a compilation of preliminary and, in some cases, more extensive concentration experiments by the Federal Bureau of Mines on low-and medium-grade fluorspar ores from three localities in Nevada and one in California. The work was done on samples obtained from Shoshone mine, Nye County, Valery mine, Pershing County, and the Broken Hills mine, Mineral County, all in Nevada, and Dirty Weather mine, Inyo County, Calif. These investigations were made to aid in the development of domestic fluorspar resources, in line with the Bureau's long-established program of conservation of mineral resources. The treatment methods employed in the experimental work described included simulated or "heavy-liquid" gravity concentration of coarse minerals and comparatively fine-grained minerals, and flotation concentration of finely-ground minerals. These methods were attempted in order to beneficiate the ores and produce concentrates which could be marketed readily, with as high a recovery rate as possible, while using simple treatment methods suitable for small-scale operation.

Jan 1, 1961

By Paul W. Jeran

Subsidence over a series of longwall panels undermining sloping terrain in southwestern Pennsylvania was monitored to verify the Bureau of Mines subsidence prediction model for the northern Appalachian coal region. Comparison of the field data to model output shows close agreement. Vertical movements over each panel ceased with the mining of the adjacent panel. Horizontal movements were significantly affected by topographic slope. The distribution of horizontal strains over each panel were similar, with a zone of compression occurring over the center of each panel. The zones of compression were flanked by zones of tension toward the rib. The magnitude of the tensions were affected by the slope. The strains developed at the completion of each panel were not significantly altered by the mining of subsequent panels.

Jan 1, 1988

By M. M. Wong

A brief investigation was made to determine the feasibility of electro-refining beryllium in a KCI-LiCI-BeC12 bath. Thin, platelike crystals of beryllium metal were produced by electrolyzing technical-grade beryllium metal beads (about 94-percent purity) as the soluble anode. Operating cell conditions were: Temperatures of 450° to 600° C.; an inert atmosphere; bath compositions of (1) 38.1 mol. percent KC1, 54.8 mol. percent LiCl, and 7.1 mol. percent BeC12 and (2) 36.7 mol. percent KC1, 52.7 mol. percent LiCl, and 10.6 mol. percent BeC12; cell voltages of 0.30 to 0.80; and initial cathode current densities of 50 to 435 a./sq, ft. Current efficiencies ranging from 87 to 96 percent were obtained. Qualitative spectrographic analyses of the metal products indicated that impurities were reduced. This technique offers the possibility of producing a grade of beryllium purer than that now generally available, which may have better mechanical properties.

Jan 1, 1960

By John A. Johnson

Tests ere conducted at the Mount Weather testing adit of the 57 Bureau of Mines on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. Equipment Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is mace of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.

Jan 1, 1939

By Frank E. Cash

Since ventilation adequate in quantity as well as quality is of paramount importance to the health and safety of men working underground in coal mines, mining officials, employees, and State inspection departments should give it the closest possible attention. MINING LAW OF ALABAMA The law governing, and regulating the operation of coal mines in Alabama was enacted in 1911 and amended or revised in 1923, 1925, 1930, and 1935. The original law and subsequent revisions were progressive steps in safeguarding the health and safety of underground employees.

Jan 1, 1939

By John A. Breslin

This publication provides an historical overview of research undertaken by the U.S. federal government over the last 100 years to improve the health and safety of our nation?s miners. Federal research efforts began with the establishment of the U.S. Bureau of Mines (USBM, or the Bureau) in 1910. They have continued over the past century, even after the Bureau?s closure in 1996. It is hoped that this publication will give the reader an appreciation for the work of mining health and safety researchers over the past century, and of the miners served by this research. Although not a comprehensive history, this report highlights the key organizational changes made within the Bureau and the federal government that affected mining safety and health research. Some mention is also made of Bureau research not directly related to mining health and safety. Note that the work classified as safety and health research has varied over the last century. For example, before 1970 the Bureau separated mining research and safety and health research. At that time, mining research included ground control and methane drainage because they had direct implications for mine safety. Explosives research was also reported separately from health and safety, even though permissible explosives research was obviously related to safety. Therefore, where budget figures from the Bureau are mentioned in this report, it is often not possible to separate safety and health research from other types of research. This history is generally chronological, with a few exceptions. Because of their prominence and direct links to Bureau research, most of the Public Health Service mining studies completed before 1970, when NIOSH was established, will be discussed in a single section, even though the work spanned many decades. Likewise, for convenience, the brief histories of the Bureau?s mining research centers are located in one section.

Feb 1, 2010

By J. B. Stephenson

The Bureau of Mines, under an interagency agreement with the Department of Energy (DOE), investigated the feasibility of hardfacing the critical surfaces of valves and similar devices by chemical vapor deposition. The purpose of this research was to increase the wear resistance of these components for use in the abrasive and erosive environment of coal gasification units. Tungsten and molybdenum coatings were produced on nickel-plated carbon steels and stain-less steels by hydrogen reduction of the metal hexafluoride at 325° to 600° C. Titanium nitride coatings were produced on low-carbon steels by the reaction of titanium tetrachloride, hydrogen, and nitrogen at 1,000° C. Titanium carbonitride coatings were produced on low-carbon steels by the reaction of nitrogen, hydrogen, and methane at 900° C. Tungsten, molybdenum and titanium nitride coatings were formed on 6-, 10-, and l2-inch (0.15-, 0.25-, and 0.30-meter) ball valve seats for evaluation in the low-Btu coal gasification pilot plant at the Morgantown Energy Research Center, Morgantown, W. Va.

Jan 1, 1979

By John A. Johnson

[Tests were conducted at the Mount Weather testing adit of the Bureau of Mines4/ on the effectiveness of spraying water along the outside of the drill steel as compared with standard wet-drilling practice. The spray equipment used in the tests was designed primarily for the control, in quarries, of dust from dry drilling with solid type drill steel. EQUIPMENT Spray equipment is made in sizes to fit different drill steel but is alike in design, the only difference being in the diameter of the ring and the number of spray holes. The device is made of cast steel and has a coating of Stellite on the inside edge that comes in contact with the drill steel. It looks like a garden spray, except that the spray holes point in only one direction.]

Jan 1, 1939

By C. E. Coleman, Joseph D. Davis

During some distillation experiments conducted by the Bureau of Mines in cooperation with the Trent Process Corporation it was observed that amalgams of heavy petroleum oils and finely pulverized coal tended to produce a denser coke than that obtainable from the coal when retorted alone . Even anthracite coal when retorted with oil yielded a coke . This led the writers to believe that by mixing a lowrank coal ( sub-bituminous or even lignite ) - with asphaltic oil and retorting it, a coke suitable for domestic fuel could be made . Thus there was contemplated the production of domestic coke and the utilization of a low- grade oil in one operation . - In order to decide on the practicability of this process , it was necessary to know the value of products obtainable by such a method , as compared with those obtained by separate distillation . A laboratory method was therefore devised , and while it was realized that no small - scale testing apparatus for destructive distillation gives results that are directly applicable to commercial - scale operations , by keeping distillation conditions uniform for comparative tests , results were obtained valuable for purposes of comparison . The plan was to distill mixtures of coal and oil in a laboratory retort , and then distill the constituents separately under the same conditions . The comparative quantities of products yielded were thus directly obtained , and their quality was determined by analysis . The following are the main points investigated : ( 1 ) Quantity and quality of coke ; ( 2 ) Quantity of oils boiling below 221 °C . ( gasoline stock) and oils boiling at 221 to 300° C . ( kerosene stock) ; and ( 3) Quantity and quality of gases .

Jan 1, 1922

By C. A. Herbert

The mine of the Alpha Portland Cement ..Co., Iroaton, Ohio, ..working in. a. bed of limestone 96 feet thick at a depth of approximately 510 feet below the surface, has established a won¬ derful safety record, having operated 6 years—frcra September 21, 1926,. to September 21, 1932 - without a lost-time accident. This mine, with 61 to 86 employees (average 68) and daily output of 1,000 to 1,200 tons of limestone, operated 1,041 days during the 6-year period, or the equivalent of 578,894 man-hours of exposure. ...... ... . Immediately above the limestone is a 20-foot .bed of hard..sandstone.. At present about 10 feet of limestone is left up as. a roof and.about. 42 feet is being extracted. Of the lower portion of the bed it is believed that about. 25 feet. ..immediately below . the .present workings is suitable for cement and will be extracted later. The mine workings are reached by two rectangular concrete shafts, one a 2-compartment hoisting shaft and the other a 2-compartment air and escape shaft- In the latter shaft one compartment is used as an airway and the other, as a cage compartment fo.r a man and material cage. .. . - . The tipples at both the air shaft: and. hoisting shaft are-of steel. The.ground landings at both shafts are fenced in with hand-operated gates in front of the cage compartments.- The two shafts and the crushing plant, which .is.a part of the hoisting shaft-tipple structure, are adjacent to the mill buildings. The rock is hoisted on self-dumping cages in 4 ton capacity, end-gate, steel cars. An electric hoist with automatic overwind device is used at both the main shaft and air shaft. The controls for the main hoist are in the tipple where the engineman is stationed and from which point he has an unobstructed view of both the ground, landing and the cage coming into the dump.

Jan 1, 1933

By Paul M. Tyler

The alkali metals , sodium and potassium , and more particularly sodium , occur abundantly in chemical combination with other elements . The elements themselves are available in metallic form but are so active chemically that they oxidize rapidly in contact merely with the air . Potassium will even catch fire spontaneously in air , and both the metals will decompose water with explosive violence . Inasmuch as they are almost as soft as wax they are not suitable for the structural or other mechanical uses characteristic of ordinary metals , and consequently the uses of these elements even in the metallic condition are based upon chemical rather than physical qualities . Sodium metal is used largely as a commercial reducing agent , but potassium metal is rarely found outside of chemical laboratories . Numerous salts and other compounds of these elements enter largely into world trade and are commercially very important , but none of these compounds except sodium peroxide and sodium cyanide are made economically from the metals . Sodium is generally considered as rather an uncommon metal , but in point of annual tonnage produced it is far more important than mercury , magnesium , molybdenum , bismuth, cadmium, cobalt , gold , silver , or the various rarer metals .

Apr 1, 1932