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By Ronald Branstetter

Gaseous and particulate exhaust emissions from 20 diesel engines in service at five underground mines were measured with high accuracy instrumentation. The engines that were tested were checked for faults or maladjustments. The vehicle and engine maintenance organization was studied at each mine and an idealized maintenance program was devised. Faults were induced in a new diesel engine to determine their effect on the characteristics of the exhaust emissions. The results, conclusions and recommendations from this investigation are presented in this final report.

Jan 1, 1983

By Thomas J. Peters

In 1979 and 1980, the U.S. Bureau of Mines and U.S. Geological Survey conducted a mineral survey of the 15,600 acre (6,310 ha) Freel Peak RARE II area (No. 5271) in the Lake Tahoe Management Unit. This study by the Bureau of Mines indicates that potential for economic mineral resources in the area is slight. The only mineralized structures in the area consists of two quartz veins. One quartz vein, at the Mountain Top Mine (fig. 1), located by Fred Denner in 1932, is estimated to contain 2,000 tons (1,800 t) of silver and copper-bearing resources. Chip samples from the vein averaged 0.61 oz silver per ton (20.91 g/t), and 1.59 percent copper. The narrow vein is not economically mineable. The other quartz vein is poorly exposed and contains traces of molybdenum. A second reported molybdenum occurrence could not be substantiated.

Jan 1, 1982

By Paul E. Loustaunau

This report describes a project in which three structured underground coal mine equipment operator training programs were developed. The project was carried out in two parts. In the first part, a research study was conducted to determine how on-the-job training is currently conducted in industry, and to determine the overall effectiveness of current on-the-job training. In addition, the possible application of the principles of social learning theory to on-the-job training was investigated. In the second part three prototypes on-the-job training programs were developed for shuttle car operation, roof bolter operation, and continuous miner operation. These programs were carefully structured to eliminate the shortcomings of current industrial on-the-job training identified in the research study and incorporated the application of relevant principles of social learning theory. The programs are prototypes which underground coal mine training personnel can use as models to develop their own customized equipment operator training programs.

Jan 1, 1983

By R. B. Schluter

Magnetite pellets were simultaneously reduced and indurated on a laboratory scale in order to determine the effects of temperature, induration time, degree of metallization, and sulfur content upon the physical and chemical properties of prereduced pellets. The reductants were commercially-pure tank gases. Among the findings were these: 1,100° C is the minimum temperature that will produce acceptably hard pellets using carbon monoxide as the reduc-ing gas. Prolonged treatment time improves the pellets' crushing strength, but the rate of improvement falls off sharply after 2 hours' induration. At 1,120° C, 75-percent metallization produces the maximum crushing strength; there was no corresponding peak at 900° or 1,050° C. Sulfur in the furnace atmosphere lowers the required induration temperature. A few tenths of 1 percent sulfur in the pellet increases the sintering rate of metallic iron in pellets by forming a liquid FeS phase that facilitates iron transfer.

Jan 1, 1968

By E. L. Garton

Michigan is becoming one of the important oil-producing States of the country. The amount of crude oil produced within its boundaries has increased from only 4,000 barrels in 19253/ to nearly 16 million barrels in 19935.4/ The Bureau of Mines method of crude-oil analysis and classification-indicates that the oils from the several producing fields are predominantly paraffin-intermediate-base, wax-bearing crudes. In general, they will yield 25 to 35 percent of highly paraffinic gasoline and about the t- me amount of kerosene and gas-oil combined, 7.2 to 15 percent of lubricating oil stock, and 20 percent of residuum with a carbon residue or about 6 to 7 percent. In addition, there appears to be some correlation between certain properties of the crude oils and both the geographical location and geological structure of the oil-producing areas within the State. These general conclusions are based on the analytical data presented in this report, which is one of a series of papers that record the general characteristics of crude oil from the many producing fields of the United States. This report discusses briefly the oil fields of Michigan and the characteristics of the crude oils produced from them. The analyses of 15 samples are given. These samples were obtained from 13 fields in 9 counties in the lower peninsula and represent crude oils produced from the Berea sandstone, Upper Traverse and Traverse limestones, and the

Jan 1, 1937

By Edward L. McHugh, Stanley M. Miller, Jeffrey K. Whyatt

The point estimation method can be applied to the safety factor (SF) equation for any specified rock slope failure mode (such as plane shear, step path, or wedge) to obtain reliable estimates of the mean and standard deviation of the SF probability distribution. A gamma probability density function is recommended for modeling this probability distribution, because it allows only for positive values and is flexible enough to provide symmetrical shapes and right-skewed, exponential-type shapes for the SF distribution. The mean and standard deviation define this distribution, which then can be integrated numerically from 0 to 1 to obtain the probability of sliding, PS (portion of the SF distribution where SF < 1.0). The overall probability of failure, PF, for the potential slope failure mass is the joint probability that the rock discontinuities are long enough to allow kinematic failure (PL) and that sliding occurs along the rock discontinuities (PS); that is, PF = PSPL. This method for estimating the probability of sliding is extremely efficient computationally, and thus, expedites slope stability simulation routines used by NIOSH software to stochastically describe rock slope behavior and assist the engineer in designing catch benches for large rock slopes. Enhanced bench design translates into increased operational efficiency and safer working conditions in open pit mines and quarries.

By C. J. Wilhelm

The disposal of brines produced with crude petroleum and natural gas has been a long-continuing problem to oil and gas operators as well as to farmers and stock-raisers in the vicinity of producing fields. An impartial appraisal of conditions pertaining to the problem of brine disposal leads to the conclusion that study of the technical consideration, with proper weight given to the economic and social factors, is the most desirable approach to this problem. Brine disposal is a problem of such magnitude in certain areas in the State of Kansas that in August 1934 a cooperative agreement was made between the Kansas State Board of Health and the U. S. Bureau of Mines for a cooperative technical study of methods of brine disposal.

Jan 1, 1935

By E. Shekarchi

A year after the Soviet Union invaded Afghanistan and replaced President Amin with their choice, President Karmal, Afghanistan remained in turmoil. In some respects, the political and economic situation in Afghanistan was no better by the end of 1980 than it was preceding the December 1979 invasion. The Government faced widespread and growing alienation and resistance, virulent factionalism within the ruling party, and an acute shortage of material. The mining sector of the country did not fare better either; the only raw material produced in a significant amount was natural gas, which was exported mainly to the Soviet Union. No statistics on production of other minerals and materials were available by yearend. Most of Afghanistan&apos;s gas production was from the Hodja-Gugerdag Field, southeast of Shibarghan. The gas flow from this field had been about 300 million cubic feet per day since 1961. An estimated 230 to 250 million cubic feet per day of Hodja-Gugerdag&apos;s production was moved by pipeline across the Amu-Darya River into the Soviet Union. Most of the remainder was transmitted eastward to a 105,000-ton-per-year fertilizer plant and an electric power station built near Mazar-i-Sharif with Soviet assistance. After the Soviet invasion, the second gasfield, Djar-Kuduk, in the Shibarghan area, was brought under production. This field, which will produce about 200 million cubic feet per day, consists of four gas zones in the Jurassic and lower Cretaceous zones between 3,000 and 8.500 feet deep. The gas has a high hydrogen sulfide content, with considerable carbon dioxide, A new treatment plant was built at Djar-Kuduk by Soviet technicians under a turnkey contract at the end of 1980. It is believed that most of the Djar-Kuduk&apos;s initial flow will be sent to the Soviet Union.

Jan 1, 1982

By Travis Q. Lyday

Mineral production in Fiji, a group of 322 volcanic islands and atolls of Melanesia in the southern Pacific Ocean, continued to be dominated by gold. However, the Fijian mineral sector remained a minor factor as a source of export earnings, Government revenues, and employment, generating only 1% of the gross domestic product (GDP), estimated as $1.2 billion.2 The largest and most important mining operation was the Vatukoula gold mine on the north side of Viti Levu, the main island. The Vatukoula Mine has been in prduction since 1932, producing about 3.8 million troy ounces of gold and 1.3 million troy ounces of silver to date. In April 1983, the large Australian mining firm, Western Mining Corp. (WMC), assumed operation of the mine in a joint venture with Emperor Gold Mining Co. Ltd., which operated the mine previously. The WMC takeover of the mine management was expected to bring in additional capital and technological expertise in order to modernize operations, increasing both efficiency and output. During the year, rate of recovery was only about 75% of the gold contained in the ore and only 40% of the contained silver. Mining at the Vatukoula Mine was done using bath opencut and underground methods, with about 60% of the ore mined attributed to the underground operations.

Jan 1, 1985

By Damon C. Gray

This report contains a recommended program of acoustic research to be conducted by the U. S. Bureau of Mines. The program is directed toward the abatement and control of machinery noise in underground coal mining operations. The study conclusions and specific problem areas which led to the definition of the recommended program are also briefly described.

Jan 1, 1971

By Michael E. Meadows

The results of tests to determine the .regional applicability of four synthetic unit hydrograph models are presented. The SCS curvilinear (Haan), SCS single triangle, Williams and TVA double triangle unit hydrograph models were tested on 271 events from 38 USDA experimental watersheds in 14 physiographic provinces. Though inconclusive due to the limited number of events analyzed, the results indicated a regional tendency for each model, with the SCS curvilinear unit hydrograph method generally performing best overall. It outperformed the SCS single triangle by predicting better shape; they differed less than 2 percent in time of peak and peak rate predictions. The Williams model performed well at Oxford, Mississippi and Coshocton, Ohio, which suggests it may be applicable to surface mined lands within the Northern and Central Appalachian Plateau and Texas coal producing regions. The TVA model is applicable to the Appalachian Plateau, specifically the Cumberland Plateau. A second test using only the SCS curvilinear unit hydrograph on 11 small watersheds and 50 events was conducted to investigate the effect of the excesss rainfall pattern on simulation results. A Green and Ampt infiltration model was coupled with the SCS unit hydrograph model to determine if peak rate and timing errors noted in the regional test could be minimized with an alternate to the SCS curve number model for determining infiltration losses. The results confirm the curve number model is the better approach to determining the excess rainfall pattern for unit hydrograph simulation.

Jan 1, 1983

By J. P. Morris

An experimental blast furnace in normal operation was quenched by substituting cold nitrogen for the hot blast air. More than 2,200 samples from the stack, bosh, and hearth were taken; 500 of these were selected for detailed analysis. Deductions are made as to the patterns of burden movement and gas flow; the reduction of iron oxides, including a comparison of ore and sinter; and the behavior of sulfur above the smelting zone. Metal and slag beads from the bosh were analyzed, as were samples from the hearth metal and slag. A brief description of a petrographic examination of the quenched burden is included.

Jan 1, 1963

By E. L. Garton

Michigan is becomining one off the important oil-producing States of the country, The amount of crude oil produced within its boundaries has increased from only 4,000 barrels in 19253/ to nearly 16 million barrels in 1935.4/ The Bureau of Mines method of crude-oil analysis and classification indicates that the oils from the several producing fields are predominantly paraffin-intermediate-base, wax-bearing crudes. In general, they will yield 25 to 35 percent of highly paraffinic gasoline and about the tame amount of kerosene and gas-oil combined, 12 to 15 percent of lubricating oil stock, and 20 percent of residuum with a carbon residue of about 6 to 7 percent. In addition, there appears to be some correlation between certain properties of the crude oils and both the geographical location and geological structure of the oil-producing areas within the State. These general conclusions are based on the analytical data presented in this report, which is one of a series of papers that record the general characteristics of crude oil from the many producing fields of the United States. This report discusses briefly the oil fields of Michigan and the characteristics of the crude oils produced from them. The analyses of 15 samples are given. These samples were obtained from 13 fields in S counties in the lower peninsula and represent crude oils produced from the Berea sandstone, Upper Traverse and Traverse limestones, and the

Jan 1, 1937

By J. G. Kirby

The number of petroleum refineries in the United States continued to decline during 1954, and according to the Bureau of Mines annual survey there were 326 refineries with a total daily throughput capacity of 8,420,630 barrels, as of January 1, 1955. The increase in capacity for the year was 413,733 barrels daily, while the number of refineries declined 11. The capacity of the average refinery to process crude oil increased during 1954 from 23,759 barrels daily to 25,830. Breaking down the crude-oil capacity increase, by refining districts; 32 percent was installed at refin¬eries located in the Texas Gulf Coast district, 25 percent in the East Coast district, and 13 percent in both the Louisiana Gulf Coast and the California districts. The Appalachian No. 1, Texas Inland, and New Mexico refining districts reported declines in capacity during the year. Additional crude-oil capacity under construction, January 1, 1955, totaled 146,800 barrels daily. Included in this total are 4 new refineries, 1 each in California, Minnesota, New Mexico, and Washington. In addition to the&apos; new facilities, equipment producing 1.49,550 barrels daily is being replaced.

Jan 1, 1955

By Doris M. Hyde

The Government of Belize maintained strict control over spending in 1982 as a means of protecting its import-dependent economy against the effects of a general worldwide recession. The modest economic performance was not expected to differ substantially from the $152 million2 gross national product (GNP) estimated for 1981. Exports and reexports were expected to decline in 1982, partly as a result of the Mexican peso devaluation. Imports were also expected to decline slightly in 1982, but the overall trade deficit was projected some-what higher than the $44 million experienced in 1981. On September 21, 1982, Belize became an independent state. As a result, the new Government became eligible for assistance from international organizations such as the International Monetary Fund, the International Bank for Reconstruction and Development (World Bank), and the United Nations Development Program (UNDP). Belize&apos;s independence from its former status as a colony of Great Britain was marred somewhat by the unsettled territorial dispute between Great Britain and Guatemala. Guatemala declared Belize was a part of Guatemala and. therefore. refused to recognize it as an independent state. Negotations between Great Britain and Guatemala continued without resolution.

Jan 1, 1984

By J. J. Jakosky, D. H. Zellers

"IntroductionThe Bureau of Mines has been conducting experiments in underground communication during a period of several years, and a brief summary of what has been done is as follows:During 1919-1920, investigations were conducted with the geophone. This instrument was used extensively during the World War for detecting enemy digging and mining operations, by means of the vibrations transmitted through the earth strata.A preliminary investigation using short wave-length (200 to 300 meters) radio equipment carried out jointly with engineers of the Westinghouse Electric & Mfg, Co. during 1922.The step was to investigate ground conduction signaling, (called T.P.S. in Signal Corps parlance)."

Nov 1, 1924

By Murray Greyson

A number of tests were made with various methanation catalysts in fixed-bed, conventional fluidized-bed, and multiple-feed, fluidized-bed equipment to develop catalysts and processes for methanation of synthesis gas. The results show: 1. Methanation reactions may be carried out in 1-inch, bench-scale equipment at high synthesis-gas throughputs with good temperature control of the reactions if a multiple-feed type of fluidized-bed design is used. 2. Nickel is superior to iron as a catalyst for the methanation of synthesis gas, unless the process is considered in terms of a combined operation that produces both gaseous and liquid products. 3. Techniques of catalyst preparation determine, to a large extent, the process life of nickel catalysts, and these techniques must be thoroughly investigated before any conclusions can be reached. 4. Enough data are available to indicate that the sulfur concentrations in synthesis gas that is used for methanation are extremely critical, and maximum process limits should be carefully evaluated.

Jan 1, 1955

Mineral production was of little significance in the country&apos;s economy, and Bangladesh was not a world-ranked producer of any mineral commodity during 1977. Natural gas was the most important mineral exploited; however, reserves were sufficient to allow for much greater production, Economically, Bangladesh made some progress in 1977-782 in its struggle against poverty, underdevelopment, and rapidly increasing population. The gross domestic product (GDP) grew 8%, mainly owing to a 13% increase in food grain production, the key economic indicator in this highly agricultural nation. GDP at current prices dropped slightly in Fiscal Year (FY) 1976.77 to $6.6 billion3 and rose to $7.2 billion in FY 1977.78. The population rose from 81 million in FY 1975-76 to about 85 million in FY 1977-78, resulting in an increase of per capita GDP from $83 to $85 during the same period. The high annual population growth rate, over 3% in 1976 and about 2.8% in 1977, was recognized by the Government as the main problem facing the country. Average density was 525 people per square kilometer. A similar density would have the entire world population living within the continental United States.

Jan 1, 1981

By Orlando Martino

This regional report covers the mineral industries of Canada and 40 countries and territories in Latin America and the Caribbean Basin. Also included is a brief description of the mineral potential of Antarctica. The Latin American region encompasses an area twice that of the United States. Latin America and Canada have a rich and diversified endowment of mineral fuels, metals, and industrial minerals. Tables 1 and 2 provide a summary view of Latin America and Canada&apos;s output of its major mineral commodities in world mineral supply in 1991 (revised) and 1992. Table 3 shows the relative importance of a selected group of minerals produced in Latin America in the world mineral economy.

Jan 1, 1994

By Thomas C. Mowatt

Chemical and petrographic studies were carried out on selected tin-bearing rock samples of contact-metasomatic origin from the Cassiterite Creek and Brooks Mountain areas, Seward Peninsula, Alaska. The tin content of rocks ranged from 0.39 to 8.9 pct. Leaching with a 20 pct hydrochloric acid solution released from 19.3 to 67.9 pct of the tin. Cassiterite was not observed in the rock samples. These results are significant with regard to tin recovery and reserve delineation in these and similar occurrences. Part of this leachable tin may be associated with metasomatic borate minerals.

Jan 1, 2011