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By Raymond W. Hiteshue, Sam Friedman, Robert Madden

Experiments were made in a semicontinuous unit to provide engineering data for designing experimental continuous systems . These systems would be used to study the hydrogasification of hvab coal and char (from lowtemperature carbonization ) to high - Btu gas . In experiments at 800 ° C and with a coal residence time of several seconds , yields of hydrocarbon gases increased from about 2,000 scf / ton of maf coal at 250 psig to 7,000 scf at 1,000 psig . With 15 minutes residence time , yields increased from 8,000 scf/ton of maf coal at 250 psig to 17,500 cubic feet at 1,000 psig . In all cases , small quantities of heavy oils were produced along with the gaseous hydrocarbons . Production of oils could be minimized with a corresponding increase in gaseous hydrocarbons by increasing the retention time of the volatiles within the hot zone . Yields of gaseous hydrocarbons from char were slightly greater than from coal under similar conditions . Although the hydrogasification reaction is very pressure dependent , substantial quantities of coal (40 to 60 percent ) could be reacted to gaseous hydrocarbons at pressures as low as 50 psig provided reaction temperatures were increased to 1,200 ° C. It was also demonstrated that a hvab coal could be hydrogasified continuously without incurring agglomeration . This was achieved by dispersing coal in a relatively large reactor with concurrent flow of hydrogen . At 1,000 psig and 800 ° C , it was possible to react about 35 percent of the coal and to produce a gas containing up to 52 percent methane .

Jan 1, 1964

By Herbert Cremer

The United States,-the largest nickel consumer in the world, produces virtually no nickel from domestic ores. Dependence upon outside nickel - sources and increasing strategic, importance of nickel focused the attention of the United States on deposits within its boundries. The most likely domestic sources of nickel are low-grade oxide and silicate deposits, such as the Cle Clum deposit, Kittitas County, Wash., and the Riddle deposit, Douglas County, Oreg. The Federal Bureau of Mines, Northwest Electrodevelopment Laboratory, Albany, Oreg. has been investigating electric smelting of low-grade oxide and silicate nickel ores. These smelting studies have been on selective reduction to produce low-carbon ferronickel. Selective reduction is based upon the relative reducibility of: nickel, iron, and chromium, in the order named, when the charge contains insufficient carbon or other reductants to reduce the entire quantity of these metals present in the ore.

Jan 1, 1954

By Leonard F. Heising

Domestic production of Metallurgical-grade manganese has contributed such a small percentage of the United States industrial demands that areas known to contain large tonnages of low-grade manganese ore have been investigated by the Bureau of Mines to reduce this country's dependence on foreign ores. A major source of low-grade manganese is the Cuyuna iron range in Minnesota. The entire Cuyuna iron range is covered by an overburden of glacial drift that, in some places, reaches depths of 200 feet or more. Prospecting and exploration must be guided by geophysical methods, drilling results, or projections of exposures found in operating mines because there are no outcrops near the productive parts of the range. Past drilling for the purpose of outlining iron ore generally was confined to the highly oxidized zones. Much of the manganese with which the Bureau of Mines is concerned occurs in thin-bedded unoxidized iron formations, too low in iron content to have been of interest to those seeking commercial iron ore. The primary objective of the core-drilling reported here was to obtain cores of different classes of manganiferous rocks and to determine whether or not the samples were amenable to beneficiation.

Jan 1, 1959

By J. M. Gomes

The Bureau of Mines, as part of an effort to maximize minerals and metals recovery from domestic resources, has investigated the feasibility of recovering heavy minerals as byproducts from sand and gravel, placer gold, and industrial mineral operations in northern California. Sand samples from about 50 locations were treated by gravity separation to yield heavy-mineral concentrates (black sands). Mineral compositions of the concentrates were determined by chemical analysis and mineralogical examination. Individual zircon, ilmenite, magnetite, platinum-group metals, thoria, and silica products were prepared from heavy-mineral concentrates by selective separation using low-and high-intensity magnetic, high-tension, and flotation equipment.

Jan 1, 1979

By Albert W. Deurbrouck

This report describes the preparation characteristics of the significant coalbeds in Russell County , Va . Almost 2 million tons of coal was mined in 1961 ; 75 percent of the coal was cleaned mechanically in preparation plants in the county . The coal of Russell County is ranked as medium- to high- volatile bituminous , contains small amounts of sulfur , and generally requires some cleaning to reduce the ash content to limits acceptable for metallurgical purposes .

Jan 1, 1963

The Government of New South Wales has granted approval for Hunter Valley Aluminium Pty., Ltd" and Alcan Australia Ltd. to proceed with the building of an aluminum smelter at Lochinvar and the expansion of a smelter at Kurri Kurri. Construction of the smelters is expected to start as soon as the consortium is finalized in early 1982. The smelters are part of a plan to increase Australia's aluminum capacity fivefold to 1.5 million tons by the mid-1980's. CHILE Construction of a $61 million lithium carbonate plant in northern Chile will be started in early 1983 by Sociedad Chilena del Litio Ltdao Production is scheduled to begin in 1984 with an initial capacity of 6,350 tons of lithium carbonate produced from a brine deposit. The firm is owned 55% by Foote Mineral Company, of Exton, Pennsylvania, and 45% by Corporacion de Fomento de la Produccion-CORFO.

Jan 1, 1982

By B. D. Hanson

An interactive computer program has been developed by the Bureau of Mines which enables the user to identify the effect of cutting system changes on relative dust generation for longwall shearer drums. The program simultaneously evaluates machine and coal seam parameters, and those parameters which the user can control. The user can change one or more of these parameters at a time to determine their effect on relative dust generation, cutting forces, and/or cost. The program is written in the BASIC programming language. A complete program listing is included along with user instructions and sample outputs. This program is a more comprehensive version of the relative dustiness index (REDI) program described in Bureau Report of Investigations 8979.

Jan 1, 1988

By Hillary W. St. Clair

This report describes a mathematical procedure for analyzing size distribution data by the method of moments. The method was applied to Andreasen's data on a variety of grinding mill products. It was found that the observed size distributions could be represented by gamma and beta distribution functions over a wide range of sizes. A computer program, written in BASIC, is described for calculating moments, distribution parameters, and the weight fraction in any size range.

Jan 1, 1969

By Arnold B. Hubbard

Automatic control instruments were utilized by the Bureau of Mines for routine assays of large numbers of oil shale samples and other bituminous materials. The standard Fischer assay method was automated by automatically controlling the heating cycles of a battery of 12 electric heaters with electronic controllers and programmers. The condensers were cooled with a modified automatically controlled refrigeration bath. The complete assembly consisted of 12 retort units, necessary control instruments, and the refrigeration bath. This equipment was capable of producing more consistent results than those previously obtained with the gas-heated retorts and of increasing the output of assays substantially with no increase in operating personnel.

Jan 1, 1965

By David B. Doan

This regional report covers 1993 mining and related activity in approximately 40 countries and territories of Canada, Latin America, and the Caribbean Basin. These countries of the Western Hemisphere, as with the United States, are endowed with a great variety of minerals, including metals, industrial minerals, and energy minerals. For most of these countries, such mineral production helps form foundations for their economies and earns export credits including hard currencies. Table 1 depicts an overall view of Latin America and Canada's production of its major mineral commodities in 1993; subsequent tables show the role of Latin America and Canada in world mineral production, trade, and import dependency on minerals from Latin America and Canada by the United States. Overall, the picture emerges of a rich mineral diversity throughout the hemisphere, attracting increasing interest and investment, and complementing the mineral resources of the United States.

Jan 1, 1995

By Will H. Coghill

This paper on milling methods and costs at a flat river (Mo.), mill is one of a series of information circulars on milling methods and costs which is being prepared by the United States Bureau of Mines, The mill under consideration treats 5,000 tons of load ore daily by table concentration and flotation. It is 25 years old, and yet it is a new mill. Research has been in continual progress at the plant since its beginning, and accordingly a day never passes without a record of change for advancement. The changes have been so orderly that no evidence of obsolete equipment remains.

Jan 1, 1932

By R. J. Tocher

Uniaxial testing was performed on coal specimens to determine the time-dependent response. The testing was carried out on coal from six mine sites throughout the Western United States and Pennsylvania. Testing configurations were varied to allow analysis of moisture dependency, stress level and specimen orientation. Several theories were presented for the behavior of coal due to moisture diffusion. Experimental results showed the correlation between the theories and the actual material response. Coal deformation was found to be highly dependent on the moisture level of the testing environment. Moisture migration causes drying and shrinkage which lead to progressive degradation of the material. The coal tested experienced a rebound if saturated after a period of drying. This type of time-dependent behavior overshadows the dependence on the applied stress level, which, however, still produces a noticeable creep behavior. Analysis of one series of creep test results was performed. A relationship was developed on the basis of a simplified rheological model to describe the coal response to uniaxial stress. Previous empirical formulations in the form of power laws were compared and their deficiencies pointed out.

Jan 1, 1980

By W. C. Holliman

This report on the characteristics of commercial aviation gasolines is one of a series of such reports. It presents compilations of' inspection data furnished on their products by 15 manufacturers of commercial grades of aviation gasoline and special data obtained in Bureau of Mines laboratories on 68 samples of these gasolines. Data are presented for 18 samples of grade 80, 20 of grade 91/98, 21 of grade100/130, and 9 of grade 115/145 aviation fuels. The gasolines are designated January 1948 production, although some of the samples actually were produced at a later date.

Jan 1, 1948

By F. S. LOTT

The number of petroleum refineries in the United States decreased from 399 on January 1, 1947, to 390 on January 1, 1948. On the latter date two additional refineries were under construction , a large one in New Jersey and a small one in Texas . This Crude oil charging capacity, based on complete facilities only , increased in 1947 from 5,569,482 barrels to 6,034,252 barrels per day , owing to material gains reported in all of the larger refining districts . great increase in effective capacity is only in part the result of the completion of major new units for crude-oil processing . Much of it is due to rearrangement and minor additions to existing facilities to permit more efficient and complete utilization . Recent experience has apparently demonstrated that many processing units are capable , with greater emphasis upon maintenance and precise controls , of sustained operations at higher volumes than were indicated in their old rated capacities . This situation doubtless has caused some upward revision in capacity data .

Aug 1, 1948

By Almon F. Robertson

The floor of Shady Valley, Johnson County, Tenn., is underlain by the Shady dolomite formation. In places the residual clay derived from this formation contains considerable manganese oxides. Nine properties in Shady Valley and two in Doe Valley were prospected by the Bureau of Mines from January 1943 to April 1943. The results obtained indicate that the ore bodies are small and spotty and, that the ore is not well-adapted to gravity concentration. The work of the Bureau was confined to the open end of the valley. One mile northeast of the Ham Greer property, Beaverdam Creek enters a rocky gorge, and it was believed that the few prospects in this area were of secondary impor-tance and, owing to the steep slope and general roughness of the terrain, that exploration with the rite', bucket-drill would be impracticable. A total of 4,398.5 feet was drilled in 131 holes. In addition, 235 lineal feet of bulldozer trenches were cut and 4.5 feet of test pits were sunk. The following nine properties were explored in Shady Valley: Bentley, Walker, Blevins, Scott, North Ham Greer, South Ham Greer, Lipford, Blackburn, and Steagall In Doe Valley, the Gerd Shoun and Brookshire properties were explored.

Jan 1, 1949

By Raymond B. Ladoo

Toward the end of 1920 , the average grades of ground feldspar offered to the pottery industry were so poor and so generally unsatisfactory that many of the largest consumers decided to take active steps for their own protection . A few of the potters made arrangements to grind their own feldspar , while others asked the Bureau of Mines to make a detailed study of the problem and to suggest methods of improvement . Accordingly such a study was undertaken, the partial results of which are outlined in this preliminary report . The outstanding features of the present feldspar industry which are of interest in this connection are stated below. (1 ) Many grinding companies do not own or control all or even a major part of their sources of crude material , but buy in job lots from many sources . (2 ) There is great need of more adequate engineering and chemical control over mines and mills . ( 3) ~ Out of date , inefficient methods and equipment for mining and grinding are in common use . (4) Little or no cooperation exists between feldspar producers , but on the contrary many feldspar companies are exceedingly secretive . This tends towards (a) preservation of obsolete methods ; ( b ) want of knowledge of the essential features of production , market requirements , and the relation between total milling and consuming capacities of the country; ( c ) inefficient and often mistaken trade practices ; ( d) unprofitable and even ruinous competition in dull periods . (5) The small size of many feldspar deposits precludes maintenance of an efficient organization at each individual mine . ( 6 ) Many of the best deposits of feldspar situated close to railroads are becoming depleted , which results in gradual lowering of grades , and increase in cost for better grades . (7) There is a lack of exact mowledge of the ceramic properties and behaviour of feldspar by some consumers , which results in ( a) purchase of feldspar on the basis of price alone , thus encouraging low production costs at the expense of quality , and ( b) inefficient and expensive cross- hauling of both crude and ground feldspar .

Jan 1, 1922

By A. W. Deurbrouck

This report describes the preparation characteristics of the significant coalbeds from which samples could be obtained in Webster County, W. Va. In 1964, approximately 825,000 tons of coal was produced in the county, of which 732,000 tons was mechanically cleaned in three preparation plants. The Sewell coal bed accounted for 94 percent of the coal produced. Twelve samples were collected from five coalbeds. Four of the samples would require upgrading to meet metallurgical requirements; two others of just over 8.0 percent ash would require some upgrading. In general the coalbed samples collected in the county were of medium-sulfur and medium-to low-ash content as received or after removal of the sink 1.58-specific-gravity material.

Jan 1, 1966

By E. H. Denny

Colorado coal-mine fatalities, which have gradually decreased since 1914, have shown a marked decline since 1924. Data on coal-mine fatalities in Colorado published by the U. S. Bureau of Mines5 indicate that the deaths per thousand 300-day workers have decreased from 9.13 in 114 to 6.14 in 1926, and that the deaths per million tons produced have decreased from 9.18 in 1914 to 4.98 in 1926. Table 1 gives fatality rates in Colorado and in the United States from 1914 to 1926 inclusive. [ ]

Jan 1, 1929

By Kenneth M. Earl

In its program of investigation of deposits of strategic minerals, the Bureau of Mines did some development drilling at the Douglas Deposit in an attempt to find an additional source of supply of copper. The deposit, which was opened in 1878, was worked until 1883 and is reported to have produced between 2 and 3 million pounds of copper. Heap-roasting and smelting and later gravity concentration were employed in ore reduction. Old slag dumps and tailing piles from these operations still remain. In 1917, the American Smelting & Refining Co., purchased the mine, and in June 1918 production was started in a 125-ton mill, using both tables and flotation. The mill was closed December 31, 1918, and soon after the milling plant Was dismantled and removed. The mine has remained idle ever since. The deposit occurs in a mineralized zone that follows the schistosity. The principal metallic minerals are pyrite) chalcopyrite, pyrrhotite) arsenopyrite, sphalerite, magnetite) slight chalcocitel and cuprite. To search for additional ore shoots and to prove the known ore shoot at depth, the Bureau of Mines drilled seven holes, which totaled 2,117.4 feet. No additional ore was developed by this work.

Jan 1, 1950

To determine the relative permeability of the soil a series of percolation tests were performed at the three locations of interest at Lanse, i.e., 3C, 03A and strip bank, and KA and KB at Kato. Soil cores were removed to 2, 8, 16, 24 and 32 inch depths with the thin wall sampler tube, each core separated from the next by about fifteen feet. Then two-foot-long thin-wall tubes were inserted into the 2, 8, and 16 inch deep holes and three-foot long tubes were inserted into the 24 and 36 inch deep holes. Each tube was tamped down about one inch further to assure a bottom seal; the tubes were filled with water and the rate of fall was measured. The test is similar to those done for septic tank percolation studies 6; but is not quantitatively related to Darcy's coefficient of hydraulic conductivity because the water can flow in three dimensions from the bottom of the tube. The measurements are dependent on the length of test, since the rate of fall is a function of the head. Therefore, it should be noted that the 24 and 32 inch deep tubes should give faster percolation rates because of the one foot greater head. At locations 03A and 3C the data show a sharp decrease in percolation at increasing depth, Table XV. However, the percolation at 03A and 32 inch depth is much higher than at 3C (0.2 vs. 0.01 inches/hour); the fragipan layer must be deeper at the 3C location since this area does experience a perched water table. On the strip bank the rates of falling head are randomly variable, appearing to be as much dependent on the particular location of insertion as on depth of placement. For example, water drained from the 16 inch tube as fast as it was added, probably into a sub-surface cavity or crevice. At Kato the tubes were more difficult to place because of interference of tree roots. For this reason 2 inch deep tubes were not inserted. These short tests at Kato were inconclusive, varying extensively when the tubes were moved. Field permeability tests were also performed in two (previously described) eight-inch diameter permeater tubes at Lanse and one at Kato. Because the soil is confined inside the tube, hydraulic conductivity can be calculated according to Darcy's flow equation. The high values reported in Table XVI experienced when the tubes were rewetted from a dry surface condition, enable us to conclude that infiltration is faster than the saturated permeability of the soil. In contrast to the falling head percolation tests, these permeability results do not show a high variation between locations.

Jan 1, 1972