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By W. M. Dressel

The objective of the research reported in this publication of the Federal Bureau of Mines was to devise a mineral dressing procedure that would concentrate zinc silicate minerals from certain deposits in southwestern Missouri. The best flotation results were obtained by batch laboratory flotation using sulfidizing agents and ethoxylated cocoamine. The flotation concentrate contained 70 percent of the zinc at a grade of 47.8 percent. Gravity concentration tests showed that 55 percent of the zinc could be recovered at a grade of 48.3 percent.

Jan 1, 1961

By R. G. Warncke, Stanley M. Walker

The United States Bureau of Mines was created by an act of Congress in 1910 as a governmental agency to work , on a national scale , toward reducing the huge annual loss of life in the production and processing of the Nation's minerals . From 1906 to 1910 , inclusive , nearly 2,500 miners lost their lives in 84 major explosion disasters , and more than 13,000 suffered fatal injuries from all causes in the coal mines of the United States . Also , conditions in the metal and nonmetal mines were proportionately hazardous during this period , and the total loss of life in all mines and quarries exceeded 3,000 annually and approximately 250,000 workers suffered serious injuries . Under these conditions it is readily understandable why Congress took notice of this " high cost of mining" , and from the investigations and hearings of the day emerged the Bureau of Mines charged with the prevention of accidents and the preservation of the health of all those engaged in the mineral industry; this has continued to be a most important part of the work of the Bureau . Throughout its existence the Bureau of Mines has had no legal authority of enforcement , except during war years , when enforcement necessary to the national security was given to it . The Bureau believes that persuasion , with factual evidence , is the proper and best way to obtain compliance with the safety suggestions made by its engineers and scientists . There is no panacea for accidents , nor will any single " approach " , instill safety consciousness in all workers , and without it accidents will occur --and occur again . To persuade men to work safely, numerous forms of appeal are required to reach the various temperaments of workers in many types of mines operating under diverse conditions .

Nov 1, 1949

Mining officials, as well as members of the Bureau of Mines staff, in their efforts to make mining safer are confronted from time to time pith complicated problems concerning solution of which there is a diversity of opinion. To reduce these differences of opinion as much as possible and to obtain a generally acceptable decision on any mine-safety question, the Director of the U.S. Bureau of Mines established the Mine Safety Board on June 1, 1924- *** to consider questions arising within any divisions of the Bureau that require a definition of tie Bureaus s collective opinion as to safety practices, safety devices, or safety methods for underground operations or open-pit mining. The approved2/decisions shall form the basis of teaching and policy for the Bureau.

Jan 1, 1935

By R. E. Peterson

Scrap iron is partially oxidized at elevated temperatures in the selective oxidation process to produce iron oxide and a dense residual metal of high purity. Investigation of the process was confined to converting automobile hulks into useful products. In one test series, compressed, sheared automobile scrap was processed at 1,000° C in a 36-foot-long rotary kiln at feed rates ranging from 300 to 1,200 lb/hr. Less fuel was required to maintain the temperature at the higher feed rates because of the heat generated from the burning of the combustibles and the oxidation of the iron. The bulk density of the residual metal exceeded 75 pounds per cubic foot. In an attempt to lower the quantity of contaminants in the residual metal, another test was designed using automobile hulks which had been prepared by ripping, a low-cost method of scrap fragmentation. Before oxidizing the ripped scrap approximately 62 percent of the total copper was removed in a tumbling, screening, magnetic separation and hand-sorting system. Cast iron made from the residual metal obtained by selective oxidation contained 0.15 percent copper; iron oxide scale obtained from the kiln averaged 0.13 percent copper. Pellets made from the scale demonstrated compressive strengths necessary for blast furnace reduction; lead and zinc were removed by volatilization when the induration was performed in a reducing atmosphere.

Jan 1, 1972

By H. R. Babitzke

To develop alloys suitable for use at elevated temperatures, columbium and tantalum were combined with tungsten, hafnium, vanadium, zirconium, and titanium, and the resulting alloys were evaluated with respect to fabricability, hardness, Electrical resistivity, strength at elevated temperatures, oxidation resistance, and bend transition. Of the 23 compositions tested, Cb-2OHf-5W-10Ti exhibited superior high-temperature properties. A recrystallized sample of this alloy was fabricable at room temperature, had a strength of 44,000 psi at 1,200° C, and had an oxidation rate of only 7.7 mg/cm2/hr at 1,000° C.

Jan 1, 1966

By Jan C. Still

The Glacier Bay subarea is that part of the Juneau Mining District (JMD) within Glacier Bay National Park and Preserve (GBNP). It is the western portion of the JMD and consists of the land between the Fairweather Range crest and the Takhinsha and Chilkat Ranges crests (excluding that land east of Excursion Inlet.) Figure B-1 shows the area. It is bounded on the north by the Alaska-British Columbia International boundary, to the south by Cross Sound and Icy Strait, and contains Glacier Bay. During 1975 -1977 the Bureau conducted a detailed study of the occurrences, prospects, and deposits in GBNP (B_4).2 This work was in cooperation with the U.S. Geological Survey (USGS) under the provisions of the Wilderness Act (Public Law 88-577). As a follow up to this earlier Bureau work, limited studies were conducted, during 1985 and 1986, as part of the JMD study. This report covers the most important aspects of the earlier studies and the 1985 and 1986 studies. ACCESS The Glacier Bay area may be reached through Gustavus airport, a paved strip which is serviced by scheduled jet airliners in the summer and air taxi services year-round. The airport is connected to Bartlett Cove (GBNP headquarters) by an all-weather road. No other roads exist in the area except a skid road to the LeRoy Mine and mill in the Reid Inlet area. Much of the Glacier Bay area is accessible through the salt water inlets and fjords which are part of Glacier Bay. Cruise ships, charter boats, and fishing boats visit these inlets and fjords during the summer months. Elevations within the area range from sea level to over 15,000 feet in the rugged Fairweather Mountain Range. More remote areas are accessible by small boat, foot, or helicopter. Glacier ice is a year-round hazard to navigation in Glacier Bay, and during the winter months some of the more northerly inlets are frozen.

Jan 1, 2012

By W. F. Watts

The U.S. Bureau of Mines has conducted research on methods to reduce and to measure diesel particulate matter (DPM) aerosols in underground coal mines. One objective of this report is to present findings from an investigation of the DPM reductions obtained by an engine-mounted integrated control system consisting of a dry system (DS) and a diesel particulate filter (DPF). Another objective is to present results from the usc of a size selective personal sampler to measure DPM concentrations in an underground coal mine. Bureau laboratory tests of the integrated dry system and diesel particulate filter (DS-DPF) have shown that DPM emissions can be reduced up to 97 pet with little change in gaseous emission concentrations. The DS-DPF is undergoing certification tests conducted by the Mine Safety and Health Administration (MSHA). Subsequent to passing all safety requirements, it will be tested in an underground coal mine. A baseline survey of DPM concentrations and aerosol size distributions in a cooperating mine was completed in August 1988. A prototype DPM personal sampler was tested during this survey. Based on results from this test, an improved unit has been developed. This unit is scheduled for extensive field testing by MSHA in 1989.

Jan 1, 1989

By James H. Cobbs

The purpose of this study is to investigate the application of boring equipment to the production of anthracite coal from steeply pitching beds. Both raise boring and augering equipment were considered. Previous studies (11) have indicated that boring equipment may have definite applications to the development of steeply pitching anthracite beds. This investigation was to carry forward previous work to determine the possible application of the two different types of equipment being considered. Previous conclusions have been substantiated by the results of this study.

Jan 1, 1975

By Russell R. Trengove

In order to extend or delimit the known ore reserves adjacent to the Comet Coalition property on the western slope of the Highland Peak Range about 8 airline miles west of Pioche, Nev., the Bureau of Mines undertook an exploration project of diamond drilling. Production figures from this property, formerly known as the Schodde, are not available, but it has been reported that small amounts of rich silver and gold ore were Shipped by wagon to a smelter in the Salt Lake valley during 1900-1910. Small shipments were reported for the period 1915-1927, also. A study of the Pioche District by the Federal Geological Survey in 1942 and 1943 was the basis for the exploration program of the Bureau of Mines in 1947 This program consisted of diamond-drilling three holes. The total footage was 2,967 feet. No. 1 hole was drilled 1,260 feet, a record depth for diamond drilling in the Pioche District. Silver-bearing lead-zinc sulfide ores are found in the Combined Metals limestone, known locally as the C.M. bed, These deposits have been formed by replacement of the limestone that is inclosed in the Pioche shale.

Jan 1, 1949

The STATE MINERAL SUMMARIES publication provides estimated data and summaries of mineral activities at the State level for 1990. Most of the estimates are based on nine months data. These summaries have been prepared in cooperation with State geological surveys or related agencies. Individual State summaries are published separately as State Mineral Industry Surveys and copies can be obtained from the appropriate State Activities field office.

Jan 1, 1991

By C. W. Huggins

The objective of this Bureau of Mines research was to compare the size distribution of respirable quartz collected at coal mines with that of several reference standards used to quantify quartz in coal mine dust samples. Particle size measurements were made on 23 samples and 4 ref-erence standards using a scanning electron microscope in the backscatter electron mode of operation, interfaced with an image analysis system. The Mine Safety and Health Administration provided the 23 respirable coal mine dust samples, which were collected at surface and underground coal mines in 7 States. The accumulated particle size measurements in-dicate three of the reference standards, minus 5-um Min-U-Sil, minus 5-um Supersil, and NBS 1878, would be preferred over the fourth, Silver Bond B, for quantitative quartz determinations in coal mine dusts by X-ray diffraction and infrared spectrometry.

Jan 1, 1985

By James J. Dowd

The investigation to evaluate the reserves of coking coal in the United States suitable for the manufacture of metallurgical coke is being made by the Bureau of Mines in three parts: (1) To estimate known (measured plus indicated) recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the fifth of a series of reports giving the results of studies by countless under part (1) of the investigation. (See appendix.) This report covers Westmoreland County, Pa., which comprises parts of New Kensington, Freeport, Elders Ridge, Pittsburgh, Greensburg, Latrobe, New Florence, Johnstown, Brownsville, Connellsville, Donegal, and Somerset quadrangles. (See fig. 1.) A short resume" of the chemical and carbonizing properties of the coals are included. Data on the coal beds in this county were obtained from mining companies, land companies, individual landowners, and other sources of authentic information. A base map for each bed in each quadrangle was made to the scale 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds up to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick. These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1951

Minerals are a fundamental component of the Nation" material and economic base. Without a continuous supply of minerals to meet growing and changing needs, the basic character of our society would be very different. The importance of minerals to the United States was reemphasized by the Congress in I970 when it enacted the Mining and Minerals Policy Act, which stated that it is the continuing policy of the Federal Government in the national interest to foster and encourage private enterprise in (I) the development of economically sound and stable domestic mining, minerals, metal and mineral reclamation industries, (2) the orderly and economic development of domestic mineral resources, reserves, and reclamation of metals and minerals to help assure satisfaction of industrial, security and environmental needs, (3) mining, mineral, and metallurgical research, including the use and recycling of scrap to promote the wise and efficient use of our natural and reclaimable mineral recources, and (4) the study and development of methods for the disposal, control, and reclamation of mineral waste products, and the reclamation of mined land, so as to lessen any adverse impact of mineral extraction and processing upon the physical environment that may result from mining or mineral activities.,.

Jan 1, 1977

By Claude W. Sill

In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of. Tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate; It seemed likely that the, same general procedure could be used in determining semimicro quantities of uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant its turn permits the use of the very stable indicator, ferroin, with its sharp color.., change and exactly reproducible blanks. Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Gleu. The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months.

Jan 1, 1952

By Roswell W. Prouty

As part of a general plan for control and economic utilization of the waters of the Missouri River Basin as well as development of its inherent power resources, the Corps of Engineers of the United States Army has under construction a rolled earth dam near the site of old Fort Randall in South Dakota. The dam is in Charles Mix and Gregory Counties on the Missouri River at a point about 922 miles above its mouth. It is approximately 125 air-line miles southeast of Pierre and 55 miles southwest of Mitchell, S. Dak. The storage reservoir to be formed by the dam will extend upstream for 150 miles and, at maximum operating pool level, will cover an area of some 107,000 acres. It will have a storage capacity of 6.2 million acre feat.

Jun 1, 1949

By J. J. Dowd

1. The Pittsburgh bed is the most important bed in Ohio County, and virtually the entire production of coal in the county comes from this bed. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of-coal in place, are estimated at 365 million short tons as of January 1, 1954. Of this total, 356 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1955

By R. R. Sayers

Mine operators and managers for a number of years have known that the maintenance of health among the workers has an appreciable financial value, In order to maintain the health, it has been found ne cessery to imow; 1. The health hazards existing in the industry as a whole and the specific hazard in the individual mine. 2. The physical condition of applicants for employment as well as that of the old employees. This can be determined only by systematic physical examination of all applicants and of regular employees at intervals of at least once a year thereafter. 3. All cases of sickness that occur among the workers. No operator or manager, or personnel, medical, or safety organization can control or prevent sickness without knowing where, when, and under what conditions the sickness actually occurs. In order to obtain information as to the hazards of industry, investigations have been and are being made of the effects of the condi- tions both in the field under usual working practices and in the laboratory. In the field several factors are generally present which affect the health. The effect of these factors may be determined by studying each of them separately in the laboratory. However, both the field and the laboratory studies are limited in value in that such studies usually have been made over a comparatively short period. While we have some information as to their immediate effect, we do not know to what extent extreme heat, humidity, the presence of dust or other health hazards are the cause of disability. Mortality statistics are probably the most easily available indices as to the hazards of industry. As an example, a study of such statistics among coal miners of Indiana shows a marked increase in the death rate in 1918.

Mar 1, 1923

By Daniel T. Rogers

The Bureau of Mines, in its alumina miniplant project to investigate alumina recovery from domestic, non bauxitic ores, has conducted research on the use of a hydrochloric acid leaching, gas sparging crystallization technology. An important element of this research is the efficient separation of undissolved, siliceous residue from AICI3 -bearing leach liquors by continuous, horizontal, countercurrent vacuum belt filtration. In an effort to calculate material balances quickly and to predict material balances based on different belt filtration configurations, the perfect-mixing-cells-in-series model (PMCS) for calculating material balances around belt filters was used. Because of the porous nature of the solids, the model produced erroneous material balances. Therefore a reliable model, the shrinking voids model, was developed postulating the presence of an unwashable voids liquor volume that decreases with decreasing liquor AICI3 concentration. This volume decrease postulation is equivalent to assuming that dilute liquors flow more freely, causing more voids liquor volume to become washable. Least-squares based computer programs are provided, which are useful not only in producing material balances from plant data but also in predicting balances for untested configurations using the same feed materials.

Jan 1, 1982

By G. L. Gates

The Bureau of Mines studied the scales formed in producing wells in the Wilmington field, California. The scales were primarily barium sulfate and resulted from the mixing of injected sea water and formation waters; there was excess sulfate in the injection water and the formation waters contained appreciable barium. After breakthrough, the produced brines were supersaturated with barium sulfate. Laboratory tests indicated that barium sulfate precipitated quickly When the supersaturated brines were agitated with crystals of barium sulfate and fairly rapidly when more sulfate solution was added. Precipitation occurred slowly on standing or under nonturbulent conditions. Both the apparent and equilibrium solubilities of barium sulfate in these brines were determined and compared with equilibrium solubilities in distilled water and sodium chloride solutions.

Jan 1, 1965

By Stephen A. Swan

Certain types of mobile surface mining equipment are required to be equipped with rollover protective structures (ROPS) capable of protecting the operator in case of a rollover accident. The Bureau of Mines has developed ROPS performance criteria for wheeled front-end loaders. This report reviews the development of rollover test procedures and subsequent testing of ROPS for 52,000-, 286,000-, and 390,000-lb gross vehicle weight (GVW) loaders. The program consisted of both dynamic (roll) and static tests to assist in the development of the ROPS performance criteria. Each test included extensive instrumentation and photographic documentation to fully evaluate the performance of the ROPS. Data summarizing side, longitudinal, and vertical force and deflections are included. The data indicate that for loaders in excess of 240,000 lb, GVW, a side force-to-mass ratio of 1.0 and an energy-to-mass ratio of 6.0 appear to be adequate criteria to protect an operator in the event of a 5400 rollover. For smaller machines, Society of Automotive Engineers (SAE) 11040 performance criteria provide adequate protection. Longitudinal loading, though not ad-dressed in previous ROPS performance criteria, was shown to be a potentially significant factor in ROPS failure. Longitudinal loading and energy criteria equal to 80 pct of side loading criteria are recommended.

Jan 1, 1988