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By G. B. Goodman, W. H. Pailes, P. D. Kaplan, I. Stachura, V. Castronova

"The risk of developing silicosis in underground coal miners, tunnel workers and some foundry workers is well-known. These persons generally develop the classic form of the disease over a prolonged period of time. Workers involved in abrasive blasting of bridges and those polishing tombstones have been reported to develop an acute form of silicosis within a few years of commencing exposure. Not well-appreciated is the potential for development of acute silicosis among drillers at surface coal mines. We report the case of a 33-year--old man who worked primarily at surf ace drilling, developed acute silicosis within three years of beginning exposure, and who initially responded dramatically to corticosteroid therapy. CASE REPORTThe patient is a 33-year-old white man who worked as a rock driller at a quarry and also at surface coal mines in western Pennsylvania since 1975. Prior to 1983, much of his work was done with a wet process in which water was applied to reduce dust generation. After 1983 he worked primarily as a driller at a surface coal mine using a dry process. He never wore a respirator. He described the dust as being so dense that he ""couldn't see anything.- In August 1986, he presented to his local physician with a complaint of pleuritic chest pain and shortness of breath. A chest x-ray film was obtained showing only a few p and q opacities. He continued working and these symptoms subsided, but the patient noted the onset of progressive weight loss. By May 1987, he had lost approximately 50 lb. In addition, he suffered profound malaise, dyspnea, migratory chest pain and arthralgia, fevers and drenching night sweats.A course of erythromycin therapy given in the hospital resulted in only fleeting improvement. Studies for Legionella and Mycoplasma infections were negative, as was a tuberculin skin test. The patient was transferred to Allegheny General Hospital in Pittsburgh on June 4, 1987.There was no history of serious medical illness, including tuber¬culosis. The patient admitted to smoking between I and 1 1/2 packages of cigarettes daily for 2 1/2 years prior to May 1987 when he stopped smoking. He denied intravenous drug abuse, homosexual activity or receiving transfusions of blood or blood products.On physical examination the patient was a thin, febrile white man who appeared chronically ill. Bilateral axillary and cervical lymphadenopathy was present. Chest examination showed restricted expansion and bilateral crackles. Examination of the heart and abdomen disclosed no abnormalities."

Mar 1, 1992

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

By Nick Derick

The continued growth of steel production in the Western States is contingent upon the development of new iron ore sources. Recent development of economical techniques for concentrating and agglomerating taconites has focused attention on the low-grade magnetite deposits near Atlantic City, Wyo., as potentially important sources of iron ore for blast furnace smelting. Therefore, the Federal Bureau of Mines has made comparative evaluations of blast furnace burdens that incorporate pellets produced from Atlantic City concentrates. The Bureau also has evaluated the relative effect of Utah coke on blast furnace performance, using a high-quality Eastern coke as a basis for comparison. This work was done in the Bureau's experimental blast furnace at Bruceton, Pa. Tests determined the maximum wind rate that could be used while a continuous stock movement was maintained in the furnace. The furnace was operated at wind rates ranging from 800 to 1,400 std. c.f.m., them maximum limit of the blowers for the 1.75 in.-diameter tuyeres used. Using a normal Utah ore burden and Utah coke, the furnace went into a tight hanging condition with a wind rate above 950 std, c.f.m. Using the experimental pellet burden again with Utah coke, the wind rate could be increased to 1,000 std, c.f.m. and probably to 1,050 std. c.f.m, before tight hanging occurs. This represents an increase of 5 to 10 pct. in the wind rate. The experimental results indicate an accompanying increase of iron production, as much as 8 pct.

Jan 1, 1961

By Bernard Porter

The rate of the heterogeneous reaction between reactor-grade yttrium and lithium fluoride in lithium fluoride-yttrium fluoride mixtures was measured using a quartz spring balance. At 950° C the magnitude of the rate of reaction is 10-5 grams of yttrium/cm2-sec. The heat of activation for the reaction is 38.3 kilocalories per mole of LiF. A surface-controlled mechanism is proposed in which LiF is adsorbed on the yttrium metal surface. An activated complex is formed when additional LiF reacts with the adsorbed LiF-metal site. The activated complex then decomposes to the products) which are lithium metal and YF3. The importance of the reaction in the electrowinning of yttrium metal from fluoride electrolytes is discussed.

Jan 1, 1967

By G. M. Kintz, E. H. Denny

Although some engineering colleges recognize the importance of instructing young engineers in industrial safety , the different institutions handle this instruction in various ways . It is believed that a recent industrial safety course , conducted at the Colorado School of Mines through the cooperation of this school and the Bureau of Mines , U. S. Department of Commerce , presents some unusual features that are of interest to other schools and to the mining public .

Sep 1, 1930

By Wing G. Agnew, Albert E. Long

"SUMMARY AND CONCLUSIONSTests conducted at Mount Weather indicate that clear water is the best bit coolant and cuttings-removal medium for diamond drilling. All of the mediums tested did show that drilling speed increased when drilling with the faster feed ratios (greatest pressure on the bits). In no case, how¬ever, did the increased drilling speed amount to over 16 percent, and even in a long hole the slight increase in drilling speed would be more than offset by the extra time consumed in setting up.Bit wear was excessive when lubricating agents were used, the most footage per bit was obtained when drilling with clear water in the normal manner, and the next best footage was obtained when drilling with circulated water containing no lubricating agent. The diamonds showed little or no wear in any of the bits, and all bits cut well throughout the tests. They were only taken out of service when erosion of the cast metal had progressed to the point where the diamonds were about to roll out. The lubricating agents evidently hold some of the cuttings in suspension, which in turn help to cut the rock but also wear the metal of the bit.No hard-matrix bits were tested, and it is possible that one or more of the lubricating agents might increase the efficiency of such a bit by keeping it sharp and doing away with the necessity of sharpening by sand blasting. Some tests are planned with hard-matrix-type bits and the same lubricating agents used in the tests under discussion, but it is realized that any drilling advantage gained by the bits sharpening themselves may but at least partly offset by excessive wear of the Pump parts."

Jan 1, 1945

By L. W. Kelly

The purpose of this circular is to show that, under the conditions prevailing in the Stony Point mine, wooden bolts were just as satisfactory as steel bolts or conventional timbering, with a reduction of approximately 80 percent in cost of material. This one fact alone is enough to justify an experiment with wood. This circular will show that production records have remained constant with both wooden and steel roof bolts. INTRODUCTION The successful use of steel roof bolts is now an accomplished fact in the coal industry, but the use of wooden bolts in place of steel is a rarity. The first experiment with wooden roof bolts was mane in 1949 in the Rio Verde mine, Norton Coal Corp., Nortonville, Ky.2/ This experiment was successful; the company obtained excellent results, but operations in the mine were suspended before enough time had elapsed to prove the value of wooden roof bolts conclusively. It is obvious that, if wooden roof bolts could be used in place of steel bolts or conventional timbering-methods, every mine operator would use word, as the cost is only a fraction of the other two methods. The Stony Point experience has proved conclusively that, under certain conditions and with a certain type of roof, wooden roof bolts can be used successfully.

Jan 1, 1952

By Harry W. Campbell

A mineral survey by Bureau of Mines personnel identified no mineral resources or mineral occurrences with development potential at prospects in the Mecca Hills Wilderness Study Area (WSA). Bentonite occurrences are in Skeleton Canyon and Surprise Canyon. Sand and gravel occurrences are numerous in and near the WSA. Much of the Mecca Hills WSA was leased for oil and gas exploration in 1983. No current mining claims or other leases were found in the study area. The Skeleton Canyon Clay Mine yielded clay to seal irrigation canals, Clay to seal ponds was also mined from the Red Top Clay Mine west of the USA. A sand and gravel pit south of the study area (near Box Canyon Wash) supplied material for local construction projects. A commercial sand and gravel pit was operating in 1983 near the mouth of Thermal Canyon 4 miles west of the WSA.

Jan 1, 1984

By M. A. Mahtab

This report describes the procedures used by the Bureau of Mines for obtaining attitudes of joints surveyed with a borescope in inclined boreholes. An algorithm for computing the dips and azimuths of the observed joints is presented. The algorithm is used to solve an example problem. A computer program based on the algorithm is listed. It is hoped that the procedures described here will be useful in treating large quantities of data obtained from comprehensive borehole surveys.

Jan 1, 1973

By F. B. Tough

"INTRODUCTION Organizations formed for the purpose of conducting conservation work in oil fields, in order to conserve and prolong the supply of crude petroleum are rare and novel. Such an organization is the Rocky Mountain Petroleum Association, Denver, Colo, As our production of petroleum can no longer keep with the consumption, the plan of organization, character of work, and results obtained by this association are well worth considering. It is hoped that the results achieved in the Wyoming fields will serve to stimulate similar organizations among operators in the state or other oil fields of the United States, The Rocky Mountain Petroleum Association, Danvers Colo., was formed in May, 1919. It comprises the Midwest Refining Co,. The Ohio Oil Co., and the Continental Oil Co. These three companies entered into a cooperative agree¬ment with the Federal Bureau of Mines whereby $30,000 would be spent under the direction of the bureau, which agreed to furnish competent men, and to furnish the work and expenditure of funds. Although the financial burden for the first year's work, now drawing o a close, was carried by only three companies, they stipulated their desire that the benefit of the work should accrue to the industry, and that the personnel employed should be as zealous to assist one operator as another, without regard to whether ha was contributing to the support of the work or not."

Apr 1, 1920

By A. Wahab Khair, S. Jung

"This paper deals with the fracturing process of laterally confined blocks of coal subjected to impact indentation. During the test, blocks of coal with approximate dimensions of 10 in. x 10 in. x 6 in. were laterally confined to predetermined equivalent in-situ stresses and then subjected to an impact indentation by dropping coal cutting bits (various shapes) attached to a known weight from a known height. During the test a number of parameters, namely surface strains (using strain gages), penetration depth (using L.V.D.T.) and acoustic emission characteristics were measured. After the test, the fractured surfaces were photographed with the aid of a camera attached to a microscope. The fracture, its intensity and extended zone within the coal blocks were mapped using sonic techniques. By correlating measured parameters, fractured zones under a given set of test parameters were identified and characterized.INTRODUCTION To improve the understanding of basic failure mechanisms in coal cutting, a better knowledge of fracture and crack regions caused by the indentation in coal is needed. This study reports the detailed experimental procedure used in fracture analysis of indentation experiments on coal specimens using the Acoustic Emission (A.E. hereafter) and sonic techniques. The relationship between microcracking and the inelastic deformation of rock was confirmed by a series of experiments in which the A. E. generated by the cracking in the rock specimen were recorded and the number of events were compared to the strain measurement. (Scholz, 1967).According to fracture mechanism theory, crack initiation in brittle materials such as rocks begins from ""flaws"" either pre-existing or induced by the indentation process itself. Rocks are pervaded by natural cracks and pores, from which numerous possibilities for crack initiation arise (Lindquist, Lai and Alm, 1984)."

Jan 1, 1989

By E. D. Gardner

"In recent years efficient safety organizations have been considered essential at all well-managed metal mines. Statistics from numerous mines throughout the country show that the expense of operation of these safety departments is repaid many times by the saving due to fewer accidents. Men trained in first aid, mine rescue and fire-fighting are important parts of the safety organization at most mines. It is more desirable, however, to lay stress ma accident prevention and fire precautions rather than on first aid and fire fighting. Both of these phases of safety work have been well developed in the Globe Miami district. The co-operative mine rescue organization* in this district under Orr Woodburn, is one of the best in the country. Mine rescue teams are kept trained at all the mines and the oxygen breathing apparatus is constantly maintained in good condition. Miners are also trained in first aid, and are offered incentives to make themselves proficient both in mine rescue and first-aid work.The Old Dominion Company is among the leaders in the safety movement in the Globe-Miami district. The safety department at this mine was established January 1, 1914, and has been developed to a high degree of efficiency. W. G. McBride, general manager of the company, takes an active part in the safety work and has given Albert Talon the safety inspector, his active support in developing the organization. The success of the department is dos largely to the ability, tact, and personality of the men directing the work.The following description of the establishment and operation of the safety organization at this mine was prepared from information supplied by Mr. Tallon."

Jun 1, 1921

By H. W. Leavenworth

Research was conducted by the Bureau of Mines to develop a technique to grow metallic fibers from a sulfide mineral. In this research, chalcopyrite (CuFeS2) was made sulfur deficient, and the remaining sulfur partitioned to the iron in the mineral to liberate metallic copper, or to the copper to liberate metallic iron. The metals formed on the surface as fibers and in the interior as spherical particles. Fiber growth is very fast. Lengths of 3 to 4 cm form in a matter of minutes, and the diameter of individual fibers is less than 1 µm. The mechanism of fiber growth is explained, and the reactions are reversible as predicted. Copper fibers can be made to grow from the surface at 400° C or to dissolve back onto the solid surface and be replaced by iron fibers at 625° C. Growth and dissolution can also be controlled to form copper/iron duplex fibers.

Jan 1, 1974

By M. M. Jones

Natural brines are potential domestic resources of minerals. The brines of Searles Lake, CA, for example, contain an estimated one-fourth of our current reserve of tungsten. A key to Bureau of Mines research to recover this critical mineral is the ability to quantitatively measure concentrations of particular constituents in the large number of brine samples and process solutions produced under a multiplicity of test conditions. This paper describes procedures used to determine arsenic, boron, phosphorus, silicon, and tungsten in these solutions by simultaneous inductively coupled plasma spectrometry. A variable in-ternal standard method was used to compensate for tungsten interference on the other analytes in tungsten concentrates, and matching standards were used to determine tungsten in raw brine. Other solutions were analyzed using normal techniques. Analytes were determined down to 1 mg/L with an average precision of 2.5 pet relative standard deviation. Accuracy, estimated using synthetic solutions and by comparison with values obtained by other methods, averaged about 2.5 pet. The methods were rapid, required little sample preparation, and provided the needed sensitivity.

Jan 1, 1985

By E. C. Tarpley

The Federal Bureau of Mines has studied solvent extraction as a means of concentrating the mineral components in coal. Solubilities of a number of American coals were determined using abietic acid as a solvent. The effect of rank on solubility was investigated, and maximum solubility was found with coals of intermediate rank. Vitrinite is the most soluble petrographic component; fusinite, micrinitc, and exinite are nearly insoluble. Spore exines also have a low solubility. Abietic acid is a hydrogen donor and reduces pyrite to ferrous sulfide. Mild hydrogenation of high-molecular-weight fragments of the coal structure to those of lower molecular-weight probably contributes to the solvent action. Even where solubility of the coal substance exceeds 90 percent, contamination of the mineral matter with coal makes identification of the mineral components difficult. Further separation might be possible by the application of float and sink techniques to the residue. INTRODUCTION Work n the solvent extraction of coal is conducted to recover commercially useful products and to characterize coal;. and obtain information on their structure. Some coals, particularly those of low rank, contain waxes, resins, and humic acids which can be removed by solvent extraction and find varied industrial uses. In World War II, solvent extraction of coal was conducted on a commercial scale in Germany to obtain a low-ash feed material for hydrogenation and to produce electrodes carbon for the aluminum industry.4 5/

Jan 1, 1960

By Alan D. Hartman

The U.S. Bureau of Mines, under a Memorandum of Agreement with the American Society of Mechanical Engineers (ASME), established design criteria for a facility to melt residues from municipal waste combustion. This facility, which is available to potential users on a cost-sharing basis, is also applicable to a variety of inorganic waste materials from smelting or melting operations. The design consists of a mechanical feed handling system, electric arc melting furnace, fume-offgas handling system, and thermal oxidizer for final offgas treatment. Screw conveyors and a bucket elevator deliver up to 2,000 lb/h of minus I-in material to a three-phase electric arc melting furnace. This unique 800-kV?A furnace has a water-cooled shell and roof to minimize interaction of the melt with the refractory lining. The volume of the hearth below the slag taphole is approximately 1.2 st of steel. The furnace is sealed, allowing atmosphere control within the furnace and fume duct by nitrogen or inert gas injection. A jet-pulsed baghouse removes particulate from the offgas and serves as an acid gas scrubber. The clean offgas is heated to 1,800° F for 1 s in a propane-fired thermal oxidizer before being vented to the atmosphere.

Jan 1, 2010

By Wm. W. Odell

A study of certain gas making and fuel problems peculiar to the gas industry of California has been made by the Bureau of Mines. The work was done at the request of, and in cooperation with The California Gas Research Council 2, for the purpose of obtaining basic information on the gas-making fuels available to California, and their applicability to the present and future needs of the gas industry in that State. The data obtained have been applied in outlining a construction program, and indicate the possibilities in efficiently utilizing fuels in making gas by other than the oil-gas process. This paper presents an outline of the study and a summary of the principal results obtained, with some of the more important conclusions and recommendations based on this data. Gas is produced in California by processes which are both unique and different from those common to other parts of the United States. The bulk of the manufactured gas is made in and distributed from two main districts which are centers of population - namely, the Los Angeles district and the San Francisco Bay district. The gas manufactured in the Bay district is, almost exclusively oil-gas, whereas that produced in the southern part of the State, where natural gas is available, is mostly mixed natural gas and reformed-gas, but oil-gas is the chief product when the supply of natural gas is inadequate. Practically all of the gas companies are equipped with oil-gas generating apparatus, and anticipate using it in the future. As the continued use of the oil-gas process to the exclusion of all other processes, depends upon a continued supply of oil at a low cost, and the prospect of obtaining such low-priced oil in the future is somewhat uncertain, the questions have arisen: What will the future gas-making process or processes be? When will it be necessary to make plans for the installation of different gas generating equipment, and what will that equipment comprise?

Jan 1, 1926

By R. H. Fernald

In investigating general problems that relate to the fuel resources of this country, and in testing fuels belonging to or for the use of the Government, the Bureau of Mines has given considerable attention to the efficiency and economic value of producer-gas power plants. Government inquiries during the past eight years not only have shown a very low fuel consumption per horsepower-hour for these plants but have demonstrated conclusively the possibility of utilizing commer- cially low grades of bituminous coal, lignite, and peat in plants prop- erly designed for the use of these fuels. The anthracite plant has been recognized as a commercial possibility for several years, although the cost of the fuel used has in general restricted these plants to com- paratively small units. The commercial development of the producer-gas power plant in the United States has been largely within the past six or eight years. In 1909 the United States Geological Survey published in a bulletin entitled "Recent Development of the Producer-Gas Power Plant in the United States" a list of producer-gas power-plant installations. The data presented in that bulletin showed a strong development in this field and led to much conjecture as to the future of this type of power. Owing to the extensive introduction of the steam turbine, however, many persons predicted the almost immediate doom of the producer-gas plant. In addition to the inroads made by this formida- ble rival, the interest of the gas-engine enthusiasts became centered to such an extent in the oil engine that the gas producer was relegated to second place by many and absolutely abandoned by some. During the past three years the belief of many who were formerly firm be- lievers in the gas producer has been that this type of power has reached its height of development in this country and that from a commercial standpoint it can no longer be regarded as a complete success. This feeling of commercial decadence has become so general

Jan 1, 1913

By M. C. Simmons, Boyd Gutorie

Desulfurization experiments at the Petroleum Experiment Station of the Bureau of Mines at Bartlesville on virgin light distillates obtained from some ‘high-sulfur’ crude oils have shown that the octane numbers of the original distillates are increased on the average about one unit, that the octane numbers of distillates with 4 ml. tetraethyl lead are increased 2 to 3 units, and that the The Petroleum Experiment Station, at the request of the Petroleum Administration for War, instigated and has in progress an investigation of crude oils of the United States to determine their possibilities for yielding straight-run distillates suitable for use as base or blending stocks to produce high octane aviation gasoline. One phase of this investigation deals primarily with so-called ‘high-sulfur’ or ‘sour’ crude oils by seeking to determine the effects of sulfur removal upon the virgin distillates prepared from these crude oils. To date, virgin distillates from several ‘high-sulfur’ crude oils from Texas, New Mexico, and Oklahoma have been prepared and desulfurized in pilot-plant distillation and desulfurization units at the Petroleum Experiment Station. The properties of the undesulfurized and desulfurized distillates were determined and compared to show the effect of sulfur removal. Results of these investigations showing the suitability of these crude oils as sources of virgin naphtha aviation base stocks have been prepared and forwarded to the Petroleum Administration for War and other approved persons. The following preliminary summary is presented to acquaint those interested not only with the present results of the investigation of several ‘high-sulfur’ Texas, New Mexico, and Oklahoma crude oils, but also to give some basic information as to certain sulfur compounds, especially their identification in straight-run distillates, their depressing effects upon the octane numbers of leaded fuels, the benefits obtained by their partial and complete removal, and some of the processes being used to effect their removal.

Nov 1, 1943

Vanadium, molybdenum, and a titanium-10 percent vanadium alloy were evaluated for their susceptibility to stress corrosion cracking in a number of corrodents. Tests were conducted utilizing conventional U-bend techniques with subsequent evaluation in a pneumatic constant-load apparatus. Vanadium and molybdenum were generally resistant to stress corrosion cracking in the media studied. U-bend specimens of vanadium showed evidence of stress corrosion cracking in 6 li hydrochloric and 18 li sulfuric acids; however, tensile stress specimens exposed to these solutions did not exhibit stress cracking. Similar results were obtained when U-bend specimens of molybdenum were immersed in 10 percent formic acid. Titanium-10 percent vanadium alloy was susceptible to stress corrosion cracking in 10-percent (2.85 li) hydrochloric acid solution. Heat treating the alloy greatly reduced its corrosion rate and its susceptibility to stress cor-rosion cracking in this medium.

Jan 1, 1965