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By W. L. Falke

Research was conducted to develop methods on a laboratory scale for recovering manganese from manganiferous slimes and limestones . The procedure is a low- temperature modification of the carbamate process , in which manganese is dissolved and the valence reduced by treating slimes and limestones with controlled amounts of sulfurous acid . Manganese ( II) hydroxide is precipitated and leached with ammonium carbamate solution , and manganese carbonate is separated by warming the leach solution . A major portion of the reagents is regenerated and recirculated . About 75 percent of the total manganese in manganiferous slimes , and from 50 to 75 percent of the total manganese in manganiferous limestones , are recovered as manganese carbonate containing 45 percent manganese .

Jan 1, 1964

By E. R. Bauer

This report presents the results of a cooperative study between BethEnergy Mines Inc., Ebensburg, PA, a central Pennsylvania coal mining company, and the U.S. Bureau of Mines to investigate longwall development entry roof instability. In-mine mapping of geologic and deformational features was conducted to reveal the major ground control problems encountered during gate road development. In addition, mining-induced pillar load monitoring was used to indicate development loading on variously dimensioned gate road pillars and to determine if pillar yielding occurred. Finally, visual observations of a variety of roof control methods were used to determine the most effective support elements for controlling cutter roof failure.

Jan 1, 1992

By J. A. Organiscak

The Bureau of Mines recently investigated dust generation and methane liberation during half-and full-web cutting at a double-drum shearer longwall face. This study was conducted to ascertain the health and safety aspects of wider web shearing at longwalls. Results from these underground tests showed that deeper web cutting reduced dust generation and methane liberation per ton of coal mined, while significantly improving shearer production rates. When cutting with the airflow (head-to-tail cut pass) full-web cutting decreased dust generation per ton by 16 pct at the shearer and 6 pct at the tailgate, with an increase in shearer production rate of 72 pct. Methane liberation per short ton also deere~sed by 36 pet at the shearer and 22 pct at the tailgate. Full-web cutting against the airflow (tail-to-head cut pass) decreased dust generation per ton by 41 pct at the shearer and 37 pct at the tail-gate over half-web cutting, with an increase in shearer production rate of 61 pct. Methane liberation per ton also decreased by 35 pct at the shearer and 41 pct at the tailgate. These improvements for full-web cutting are a reflection of improved cutting efficiency (less dust and methane produced from cutting) and less new face area exposed per ton of coal mined (less methane liberated from face per short ton of coal mined).

Jan 1, 1988

By G. E. McElroy

Ventilation-pressure surveys are required to determine the rates of pressure losses in various parts of mine-airway systems. These may be determined directly by differential pressure measurements or deduced from absolute pressure measurements, Despite the confusion caused by its inverted nonlinear scale, the altimeter has special application to pressure surveys in mines in which only small differences in elevation are involved, as is true for most of our large bituminous-coal mines in these, the judicious use of information obtained by pressure surveying can result in greatly improved working conditions as regards health and safety and, in many instances, can yield large financial returns. The main purposes of this report are to discuss methods of using altimeters for pressure surveys and to present the particular methods of making surveys and calculating the results of surveys used by the Mine Ventilation Section of the Bureau of Mines.

Jan 1, 1957

By A. C. Fieldner, G. W. Jones

Tests were made at the Government Fuel Yard , operated at Washington , D. C. by the Bureau of Mines , Department of the Interior , in order to determine and improve the adjustment of the carburetors on the trucks used for transporting coal from the Fuel Yard to the different Government buildings in Washington . The tests were made possible through the hearty cooperation of G , S. Pope , engineer in charge of the Fuel Yard . Joseph Burrows and A. E. Foote of the garage department assisted during all the tests and supplied information on the mileage obtained by the trucks for the months preceding and succeding the time the tests were made . The Mack trucks used range in capacity from 2-1/2 to 7-1/2 ttoonnss .. The majority of the carburetors were Stromberg G- 3 type , as shown in Table 2. During the winter months , when the demand for coal is heavy , from 30 to 35 trucks are used . At the time the tests were made , only about ten of the trucks were in daily use , owing to the small demand for coal during the summer months , and scarcity due to labor conditions . Samples of the exhaust gas were taken on the trucks kept in service for summer hauling in order to determine the carburetor adjustment as used . Changes were then made to a more economical adjustment wherever possible , without sacrificing flexibility of operation and power . In every case the adjustments were maintained for maximum power , but were adjusted to the leanest position to give that power . In all but one case the carburetors were found to be adjusted too rich for maximum power and economy . These results are considered in detail in a later part of this report .

Jun 1, 1923

By Lloyd A. Morley

The primary goal of this research report is to discuss safety considerations involved in the use of lead-acid batteries for traction purposes in underground coal mines. In order to arrive at the objective, the topic of battery safety has been divided into two specific areas. The first deals with the fact that batteries emit hydrogen gas during and after the charge cycle. Hydrogen gas can be the source of dangerous explosions or mine fires. The second major topic deals with the electrical nature of the battery and battery-charging systems, which also provides a source of mine fires as well as electrocution hazards. In addition to the discussion on battery safety, a literature review has been undertaken to acquaint the reader with some basic concepts inherent to the battery usage process. The result of this research is a set of design specifications and procedural recommendations directed at improving the safety factors inherent in any underground battery usage scheme.

Jan 1, 1977

By Edward D. Thimons

Several types of inflatable stoppings, developed under Bureau of Mines contract for use as mine air barriers during underground production, have been tested by the Bureau. All of the stoppings tested showed significant internal leakage initially but, in all but one stopping, the leaks were sealed with limited effort The stoppings were tested underground in two western noncoal mines under production conditions. The results from the Colorado molybdenum mine showed the stoppings to be generally unsatisfactory for daily mine usage if they are deployed near blasting areas or in locations where near-perfect air seals are required. They were very susceptible to blast damage and seldom were better than 90 percent efficient as air barriers. However, stoppings tested in the New Mexico uranium mine were located substantially distant from any blasting. Because slight leakage past the stoppings was acceptable, they proved very satisfactory in that application.

Jan 1, 1976

By Allen S. Smith

Analysis of the helium content of a natural gas presents more than the usual difficulties encountered in applying the thermal--conductivity method because of the relatively small amounts of this inert gas present and the wide variation in the other constituents. However, the numerous advantages of this method and its adaptability to continuously recording and control instruments make it worthy of consideration. A specific application of the method described yields quantitative results only when used with gas mixtures of known qualitative compositions which vary within predetermined limits. Periodic analyses for the helium content of a producing gas well may be conveniently made by an absorption method3/ and a continuous analytical method is not necessary for this purpose. Natural gas containing 1.75 to 1.90 percent of helium produced from Government-owned wells is processed in the Amarillo (Texas) Helium Plant of the Bureau of Mines. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company4/. As complete recovery of the helium in the raw material is not economically practicable, the processed gas contains 0.1 to 0.3 percent of helium, depending upon conditions of operation;- Production is checked against the helium removed from the gas, which before the installation of the thermal--conductivity apparatus was calculated from the analysis of a cumulative sample of the processed gas. As conditions of operation affect the residual helium content to a large extent, a composite sample was an uncertain index of the efficiency of the process.

Jan 1, 1934

By P. Kovalchik

The Bureau of Labor Statistics (BLS) classifies hearing loss as a separate illness category. Hearing loss accounted for 11% of all illnesses in 2005 (U.S. Department of Labor Bureau of Labor Statistics, 2006a). According to occupational data for coal mining provided by the Mine Safety and Health Administration (MSHA) from 2000 to 2005, operators that exceeded 100% noise dosage were from only seven types of machines: auger miners, bulldozers, continuous mining machines, front end loaders, roof bolters, shuttle cars (electric) and trucks (Title 30 CFR Part 62, 2000-2005). Roof bolting machine operators rank second among all underground machine operators that exceed 100% noise dose. There are approximately 600 underground coal mines with 3,930 roof bolting machine operators (U.S. Department of Labor, Mine Safety and Health Administration, 2005; U.S. Department of Labor Bureau of Labor Statistics,

Jan 1, 2008

By F. B. TOUCH

This bulletin deals with a topic that is exceedingly wide, and will doubtl~ be under consideration and discussion so long as there are enough known deposits of oil and gas remaining in the earth to make their revelopment profitable. The Bureau of Mines has repeatedly called attention to the importance of protecting oil or gas sands from the encroachment of water, and the purpose of this paper is to summarize existing knowledge of methods and devices. Water may gain access to an oil-bearing formation from several sources-from water sands above or below those. containing the oil, or by encroaching through the oil sands as the oil is withdrawn. In short, it may enter a well from the "top, bottom, or side." Such ingress of water is a most serious detriment to the recovery of oil from the ground. As the art of drilling and developing oil properties has progressed, increasing thought, labor, and money have been expended on various methods, devices, and equipment for arresting the migration of water from its normal subsurface position into the porous strata containing valuable oil or gas accumulations. At an early stage in the oil-field development of California, it became evident that considerable modification of accepted drilling practices was necessary in order to meet the conditions imposed by the poorly consolidated shale, clay, sand, and bowlder beds penetrated, as well as the hard layers of sandstone and calcareous shale, which vary greatly in thickness, hardness, and frequency. These hard streaks are commonly called " shell," and are so reported in the well logs. As deeper and deeper territory was prospected, drillers from the older fields of the Ea,st, as well as from Texas and Louisiana fields, took part in the operations. Xhe practice evolved was thus based on the wide experience of a most cosmopolitan group of men who, considered as a group, were not hampered by being limited to the knowledge of the practice at any one locality.

Jan 1, 1918

By Oliver Bowles

The exingencies of a world war have brought home to the American public, especially the people of the. Eastern States, the urgent need for conserving fuel. Transportation problems in the East have created an unprecedented situation wherein fuel-oil supplies are greatly restricted, and the consequent increase in demand for coal further complicates the problem of transporting and storing that commodity. People should awaken to the need for utilizing every possibly means of conserving to fuel, even to the extent of reducing the temperature in their homes.

Jan 1, 1942

By R. L. Grant

Study of the ignition of firedamp by explosives and the phenomena that underlie it is one of the long-term investigations of the Bureau of Mines. This report is the third in e series by the Explosives Branch summarizing the progress made at Bruceton in this study. The first paper described preliminary work on small, carefully controlled cannon shots the second discussed the results of suspended shots.5/ In this paper, experiments are described and interpreted that extend and support the concept of ignition presented previously. ACKNOWLEDGMENT The authors wish to thank Bernard Lewis, former chief, Explosives and Physical Sciences Division, and Guenther von Elbe, former chief, Physical Sciences Branch, Explosives and Physical Sciences Division, for their guidance and constructive interest.

Jan 1, 1954

By William H. Pomroy

Spontaneous combustion fires involving high-sulfide-content ores are a relatively infrequent yet serious safety hazard in mining. They are also the cause of lengthy mine shutdowns because they typically occur in areas of a mine where abundant fuel material is present but which are inaccessible for fire fighting. This Bureau of Mines report describes research to design, fabricate, and test in the laboratory and field a system that warns of spontaneous combustion fires in metal mines. Overall performance of the detection system was found to be satisfactory, in that the system was capable of reliably detecting low levels of combustion products believed to indicate the preflaming stage of spontaneous combustion in metal mines. Installation of similar systems in mines with a high risk of spontaneous combustion is recommended. Principal operating problems and recommended corrective actions are also discussed.

Jan 1, 1987

By J. L. Eakin

The Bureau of Mines determined agents that are effective in foaming heavy brines and oil from gas wells in severe concentrations of sodium chloride, in severe concentrations of calcium chloride, or in moderate oil-brine mixtures. Dynamic foam tests were designed to select the more effective foaming agents. Numerous foaming agents were tested in concentrated simulated brines, in oilfield brines having varied concentrations of ions, in heavy natural brines, and in a commercial brine generally used as a reservoir pressure-balancing fluid. Several agents were detected that could perform efficiently in the field under the most severe saline conditions. Agents that promote foaming in oil-brine mixtures were also determined.

Jan 1, 1965

By W. P. Huleatt, R. B. McCulloch

"The Big Four zinc-deposit, directly above the north bank of the Green Mountain Reservoir on the Blue River, Summit County, Cole., was discovered in 1937 by the present owner, Walter McDaniel, who lives on the property. Mr. McDaniel, together with members of his family, have worked the mine on a small scale since its beginning and have shipped quantities of sorted high-grade ore to the International Smelting Co. at Tooele, Utah, and the Combined Metals Corp. at Bauer, Utah. More recently, parts of the nine have been operated by lessees.The property had been examined previously by the Federal Geological Survey, and the geological report was made available' to the Bureau of Mines.The Big Four mining claim was located in 1937 by Walter McDaniel and his wife Frances,- who had been prospecting in the vicinity since 1933. The discovery of the high-grade zinc deposit caused considerable excitement, as it had not been regarded as a mineralized area.Mining was begun in 1937 and carried on until 1944 by Mr. and Mrs. McDaniel with the help of a few hired miners. During 1944, parts of the mine were leased: to various parties Who produced small quantities of ore but did no development work.Shipments during 1941 .totaled 752 tons; during 1942, 387 tons; and during 1943, 510 tons. From the beginning of 1944 to April of that year, 98 tons wore produced and shipped to Utah,Since the lessees began operations, a grade of 30 to 35 percent zinc has been maintained by careful sorting. No production has been recorded for 1945.The Big Four mine is situated on Colorado State- Highway 9 between Dillon and Kremmling on the south face of Green Mountain overlooking the Green Mountain Reservoir, a Federal irrigation project on the Hue River, Green Mountain rises 1,600 feet above the general level of the valley to an altitude of 9,408 feet and the surrounding terrain, i s correspondingly mountainous and rugged."

Apr 1, 1946

By R. V. Higgins

Tarner (1),3/ Muskat (2), and Schilthuis (1) have presented methods of calculating oil recovery by the expansion of dissolved gas with and without return of gas to the reservoir. Although electronic computers have eliminated the tedious and time-consuming calculations (4) required by each of these methods, many petroleum engineers do not have access to electronic computers. For these engineers a short method is presented that uses the Tarner method as a base. Moreover, for engineers who have access to computers and have not as yet prepared a program, the short Tamer method requires less computer time than the long iterative methods. In the proposed short method, no plotting of the calculated data is required to determine a point of intersection described in the original Tarner presentation, as only one calculation is needed to determine the value sought, or two calculations if greater accuracy is desired.

Jan 1, 1960

By Jeffrey S. Walker

Abandoned underground mine openings are susceptible to collapse because of the mining methods used, the character of the overburden, and the typically large, wide entries with minimal roof support. The final effect of the collapse of the underground workings is surface subsidence. To reduce the probability of subsidence, methods to backfill the mine void with various types of materials have been developed. This U.S. Bureau of Mines report describes the available technologies for subsidence abatement and discusses their operation and application. The basis of these abatement methods is the replacement of the mined material with mine waste. Backfilling of mine voids is the most common method of stabilization used to abate subsidence and protect surface structures. Hydraulic flushing and grouting, using remote methods from single or multiple boreholes, are the most often-used methods for the placement of backfill material. Other subsidence abatement techniques are available and may be more appropriate under different conditions. These other techniques include pneumatic stowing, either by in-mine or remote methods, and various point support methods that do not completely fill the mine void and are used for the protection of small areas of the land surface and surface structures.

Jan 1, 1993

By E. A. Loria

High-quality sheet of electrowon molybdenum was attained by a sequence of procedure on pressed and arc-melted crystalline powders. The procedures included high-temperature, high-vacuum sintering treatments and the use of metal deoxidizers instead of carbon to improve the mechanical properties of the molybdenum sheet. Rolled sheet 60 mils thick was evaluated by tensile and bend tests, hardness measurements, microstructures, and recrystallization treatments. After stress relieving, yield strength ranged from 85,000 to 110,500 psi (0.2- percent offset) and ultimate strength ranged from 87,200 to 117,250 psi with 4.5- to 25-percent elongation observed for arc-melted sheet, and 5.0- to 23- percent elongation observed for powder metallurgy sheet. In room temperature bend tests the sheet yielded plastically, indicating that the ductile-brittle transition point was below room temperature. The diamond pyramid hardness (DPH) of the molybdenum sheet changed from 214 to 293 DPH for the stress-relieved condition to 177 to 185 DPH for the fully recrystallized condition. The brittleness of recrystallized molybdenum, reported by other investigators as characteristic of sheet prepared from commercial-grade hydrogen-reduced powders, was not in evidence. Recrystallized tensile specimens pulled at room temperature had an average elongation of 31 percent.

Jan 1, 1966

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Jan 1, 2012

By A. J. Miscoe

A unique machine for inducing bending fatigue in wire ropes was built at the U.S. Bureau of Mines' Pittsburgh Research Center. This machine can produce nine levels of degradation through repetitive cycling of long samples of wire ropes of the types used in the mining industry. This report provides an analysis of the results of the first wire rope to be fatigued on this machine. These results have indicated that as a wire rope accumulates bending cycles, its strength first decreases because of wear and then in-creases due to cold working of the wires. As the amount of cold working increases, more and more of the embrittled wires break and the strength of the rope decreases rapidly. In this test, application of several of the regulatory retirement criteria to various sections of the rope suggests that there may be some inconsistency among them.

Jan 1, 2010