Search Documents

By Sidney Katell

This report covers the period January 1963 through December 1963; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fifth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from the following sources:

Jan 1, 1964

By Liming Yuan

A computational fluid dynamics (CFD) study was conducted to model effects of coal properties on the potential for spontaneous heating in longwall gob (mined out) areas. A two longwall panel district using a bleeder ventilation system was simulated. The permeability and porosity profiles for the longwall gob were generated from a geotechnical model and were used as inputs for the three dimensional CFD modeling. The spontaneous heating is modeled as the low temperature oxidation of coal in the gob using kinetic data obtained from previous laboratory scale spontaneous combustion studies. Heat generated from coal oxidation is dissipated by convection and conduction, while oxygen and oxidation products are transported by convection and diffusion. Unsteady state simulations were conducted for three different US coals and simulation results were compared with some available test results. The effects of coal surface area and heat of reaction on the spontaneous heating process were also examined.

Jan 1, 2008

By Stephen A. Hare, O&apos

Powder metallurgy processing of commercial Raney nickel powders was examined. The typical angular particle shape, in conjuction with aluminum present in a eutectic phase, facilitated interlocking leading to excellent green strength after compaction. Density and porosity as influenced by the compacting pressure were studied over the range of 37.5 to 207 meganewton per square meter (MN/m2). Sintering in an inert atmosphere from 575° to 850° C caused a volume increase which is attributed to a solid state reaction between Al and Ni2Al3 phases. The reaction is 3Al + Ni2Al3 ? 2NiA13. A thermal pretreatment of 70 hours at 700° C was required to prevent this reaction from occurring during sintering. Density and porosity as a function of compacting pressure and sintering temperature were determined after a thermal pretreatment of the powder.

Jan 1, 1976

By B. W. Haynes

With the national focus on energy, the combustible fraction of urban refuse is being extensively considered as a fuel supplement for coal in the generation of heat and power. The objective of these analytical studies by the Bureau of Mines was to determine the concentration of major, minor, and trace elements in the combustible fractions collected at various locations in the Bureau's urban refuse recycling pilot plant located at College Park, Md. The samples processed through the plant were submitted by various municipalities that are considering resource recovery as an alternative to landfill or other means of disposal. Twenty-five elements were determined in samples from six geographic areas and were compared with element concentrations found in typical coal samples.

Jan 1, 1977

By J. G. Walters

This report presents the results of an investigation in Which the chloroform solubilities of coals and chars are related to rank, temperature of thermal treatment, time at a given temperature, vacuum thermal treatment, plasticity, oxidation, blending, and mass spectral analyses and molecular weights of the extracts. It was found that the quantity of chloroform extract obtained from chars can be altered by creating a vacuum above the charge during preparation of the char, increasing the time at temperatures within the plastic temperature range, and by utilizing different rates of heating to attain a given temperature. Relationships found between the chloroform solubilities of chars produced at temperatures within the plastic temperature range and the relative fluidities in this temperature range indicate that the chloroform-soluble portion of the char is a significant component of the plastic mass. Chloroform-extract yields from chars made from blends of coals cannot be calculated from chloroform-extract yields obtained from chars made from the component coals.

Jan 1, 1967

By Lloyd A. Morley

Two mine electrical power system simulations are presented. The first is a batch processed procedure capable of modeling a single mining machine consisting of a number of motors operating under various loads. These loads are the mechanical torque loads present at the motor shaft. The second simulation is a more flexible tool for modeling entire mine electrical power systems~ Detailed analyses of bus voltages, transmission-line power flows, and machine behavior are possible. This simulation operates interactively and the power system is configured as the user responds to program generated questions and requests. Development of the theory behind the programming, as well as detailed explanations of the models, is presented. Examples are provided to demonstrate simulation capabilities.

Jan 1, 1978

By E. S. Burnett

The temperature entropy (T, S) chart? of thermodynamic properties of nitrogen herewith presented is a complete (1949) revision and a considerable extension of similar charts prepared by the author for use of the helium section of the Bureau of Mines about 25 years previously on the basis of inadequate data then obtaining. During the interval since that early effort, much experimentally determined information on nitrogen properties and behavior has been published, which now permits a more nearly accurate layout and more extensive charting of these relations.

Jan 1, 1950

By S. C. Termes

The Bureau of Mines conducted research on the flocculation of various minerals with insoluble cross-linked starch xanthate (ISX) to determine its potential as a beneficiation technique for low-grade, highly dissem-inated ores and for selective desliming. Covellite, chalcocite, pyrite, pyrrhotite, chalcopyrite, bornite, sphalerite, galena, and molybdenite fines flocculate with ISX. Floc formation, floc size, and settling rate are dependent on pH, with the pH dependence differing for each mineral. Quartz is not flocculated by ISX. Experiments to obtain selective flocculation of sulfides from quartz were attempted. Good selectivity was only obtained for the bornite-quartz system. postflocculation separations resulted in flocculated bornite in grades as high as 92 pet. Evidence is presented that the flocculation of many of the sulfide minerals with ISX may involve covalent bonding of the xanthate group to lattice metal site(s).

Jan 1, 1983

By M. E. Volin

The Buckeye manganese deposits are in Stanislaus County, Calif., about 33 miles south of Tracy. From 1917 to 1919 the deposits produced 13,370 tons of ore reported to average 46 percent manganese and 14 percent silica. The deposits are confined to two areas of' development, known as the north mine workings and the south mine workings, about 700 feet apart horizontally. Mineralization occurs chiefly as rhodochrosite and psilomelane interbedded in cherts of the Franciscan formation. As a part of the Bureau of Mines program of investigation and development of domestic mineral deposits, a development project was started November 25, 1940, and completed June 27, 1941. The Federal Geological Survey cooperated by mapping the topography and geology and logging the drill cores. The program included road and. trail building, trenching, underground excavation, diamond drilling, and sampling. The following pages mention the location, brief the history, and note the physical .features of' the district. Mine workings are sketched, the deposit is described, and the plan of the project is noted. The work performed by the Bureau of Mines is explained in the concluding pages with a summary of the drill-hole logs.

Jan 1, 1949

By Thomas Fraser

IN a Nation-wide appraisal of coking-coal reserves and of the feasibility of expanding them by upgrading marginal coals, it is natural that the Pittsburgh region of Pennsylvania should be considered first. Here, where the American iron and steel industry started, the Pittsburgh coal bed is of paramount importance. The use of coke in iron blast furnaces is said to have begun with the discovery that good blast-furnace fuel could readily be made by a simple method of coking Pittsburgh coal. To the present time, the prosperity of the steel industry has depended largely on utilization of this great coal reserve and the cheap transportation afforded by the Monongahela River system. OBJECT AND SCOPE OF INVESTIGATION The initial project in the study of upgrading marginal coking coals was laid out in this area, which contains large reserves of Pittsburgh coal contiguous to the Monongahela and its navigable tributaries. Much of the Pittsburgh coal remaining here is known to have a high sulfur content. The problem of reducing the sulfur to meet metallurgical requirements already has received much attention, and it is considered to be one of the most difficult technologic problems in the field of coal washing.

Jan 1, 1950

By Dean C. Holt

This work was done to appraise the potential of titanium minerals in known titanium- bearing placer deposits and potential titanium- bearing placer areas in western Montana . Reconnaissance studies were made of more than 225 stream areas . Churn drilling and other placer exploration techniques were used in sampling eight deposits . The sampling results indicate that areas containing more than 10 pounds of ilmenite and other titanium- bearing black - sand minerals per cubic yard occur in the Bitterroot , Upper Clark Fork , and Jefferson River drainages . The chief source for the constituents of the black sands appears to be the Idaho batholith , and the highest black - sand concentrations are generally found near the source . Sample testing methods include gravity and magnetic separation and visual microscopic as well as chemical and radiometric analyses on deposits sampled in detail .

Jan 1, 1964

Real economic growth for 1988 may fall short of the 3.3% projected by the U.S. Department of Commerce in August 1988 be-cause the summer drought and intense heat in many areas curtailed output more severely than expected. The economy grew at an average annual rate of 3.0% for the first three quarters of the year, slowing in the second and third quarters. Export growth, which occurred even as the dollar edged up com-pared with other industrial country currencies, was an important factor in the expansion. Notable gains were posted in sales of machinery, computers, aircraft, chemicals, and telecommunications equipment. Imports increased, but not as much as exports, and the U.S. trade position was still much improved from that of 1987. Personal consumption expenditures grew slightly faster than the economy as a whole. Purchases of consumer durables showed notable strength in the first half of 1988, but slowed down in the third quarter. [ ] Despite the moderate rise in interest rates, business spending for new plant and equipment also rose and contributed to 1988 gross national product (GNP) growth. Both new business investment and export demand spurred orders for U.S.-made machine tools. Orders for machine tools for the first 8 months of 1988 were almost triple those for the corresponding period in 1987.

Jan 1, 1988

By P. J. McDonough

The Bureau of Mines designed and tested a hardware-software system for measuring on-line corrosion rates of materials in a rod mill in operation. Currents ranging from 10-6 to 10-3 A and potentials in I-mV increments were converted to a digital signal. The digitized data were frequency-modulated and transmitted from a rotating ball mill to an FM receiver, where they were decoded by computer and then processed in real time using assembly language software. This design approach would allow accurate measurement and control of systems where signals of small amplitude and large ranges are present.

Jan 1, 1988

By Guy A. Johnson

This Bureau of Mines report summarizes the results of efforts to develop reasonably priced, reliable mine shaft fire and smoke protection hardware for metal and nonmetal mines. The hardware was incorporated into a viable prototype system that would minimize fire and smoke hazards. The design of the system had to be sufficiently flexible to be utilized in a wide variety of metal and nonmetal mine shaft and shaft station configurations. As a result of long-term, rugged field tests, an improved (second generation) system was developed. The hardware is now commercially available.

Jan 1, 1978

By Robert W. Freedman

Vacutainers are employed by the Bureau of Mines and the Mining Enforcement and Safety Administration for sampling mine air and other atmospheres containing fixed gases, low-molecular-weight hydrocarbons, and products of combustion. Tests were conducted to study shelf life of evacuated samplers prior to sampling and also to check the stability of sampled gases prior to analysis. An unexplained phenomenon, slow accumulation of carbon monoxide in evacuated samplers, occurred after a few weeks' storage; levels were low but increased with time and could pose a problem for critical applications. Accordingly, attempts to halt CO release by additional means of treatment were made, and storage at low temperature was found to be effective.

Jan 1, 1978

By S. M. Shelton, R. B. Fisher, M. M. Fine

"INTRODUCTION The Batesville manganese district lies in the southern part of the Ozark region, mostly in Independence County but partly in Sharp, Izard, and Stone Counties of north central Arkansas.Oxides, carbonates, and silicates of manganese are found in the district. 4/ Carbonate ores have been mined from time to time, but the reserves of potentially commercial ore are chiefly black manganese oxide minerals.The district has produced manganese ore for many years. lip to and including 1933, 160,804 long tons of ferruginous manganese ore (10 to 35 percent manganese) and 140,277 long tons of metallurgical ore (35 percent or more manganese) were shipped;./ most of it was wad orThe term ""wad ore,"" used locally to designate the soft, clayey de¬posits of oxide ore, is a partial misnomer. The ores contain a soft, low-specific-gravity mineral of indefinite composition, which can be designated as wad, but coarse and fine particles of psilomelane and hausmannite, with a smaller proportion of braunite, pyrolusite, and indefinite manganese silicates, are also present. Large and small lumps of high-grade, hard manganese oxide minerals are found, frequently embedded in a soft, black matrix of fine particles of manganese oxides mixed with gangue."

Jul 1, 1942

By Robert B. Fulton

Summary of data and estimates for 52 fluorspar properties in the following 13 foreign countries: Mexico Thailand China (PRC) Morocco Tunisia Italy Spain South Africa France United Kingdom Kenya Namibia Federal Republic of Germany Data includes deposit type, resource tonnage and grades, mining and beneficiation methods, annual production, fluorspar products and by-products, manpower requirements, capital and operating cost estimates. For operating properties, engineering and cost data have been developed for present and anticipated levels of production. Hypothetical operations have been assumed for undeveloped deposits.

Jan 1, 1984

By B. J. Arnold, F. F. Aplan

"The captive bubble and sessile drop contact angle techniques have been used to evaluate the hydrophobicity of petrographically identified coal macerals. The magnitude of the contact angle on vitrinite is shown to be a function of coal rank ( %C, %0 and % vitrinite reflectance), increasing with increasing rank to a maximum for low volatile bituminous rank coals then decreasing for anthracite. The least data scatter is found when vitrinite reflectance is used as a rank parameter. Contact angles measured or estimated for other discrete macerals, indicate a variation in hydrophobicity based on coal type. These data correlate well with known flotation results. Coal is a heterogeneous mixture of plant remains and associated minerals that have undergone chemical and physical changes by biological and geological processes. These plant remains form coal macerals, discrete organic entities in the coal which have characteristic chemical and physical properties. As the differing chemical nature of each maceral will affect its behaviour in processes such as carbonization the separation of macerals during coal preparation may provide an important asset in coal utilization.Separation of some of the macerals based on specific gravity has been achieved in the laboratory, and by Sun and Cohen , in a study of two Pennsylvania bituminous coal preparation plants. It was indicated that the lighter exinites report almost exclusively to the clean coal while the denser inertinites are concentrated in the higher gravity fractions. The Longwy-Burstlein process6 took advantage of the difference in hardness or friability of the macerals by using impact breakage followed by screening to remove the more friable vitrain,clarain and fusain. The remaining durain, often high in spore content, was then recrushed. The re-mixed fractions produced the optimum size for obtaining the best coke strength for a particular coal.Separation or concentration of rnacerals by froth flotation largely depends on differences in the hydrophobicity of the macerals. Sun and Cohen 5 . indicated an order of decreasing floatability as exinite, vitrinite and inertinite, while a Russian study (as cited by Brown 7 ) showed that vitrains floated more readily than the duller types. More recently, Hirt and Aplan8 showed that 'pseudovitrinite' floats somewhat faster than does vitrinite while fusinite floats very slowly. Olson and A plan found that vitrinite floated easily while substantial quantities of the non-floated coal contained fusinitic material. Burdon noted that vitrinite is more floatable than semifusinite, and Sarker et a/. 11 have shown that vitrinite is selectively concentrated by froth flotation and oil agglomeration. Sun indicated that flotation, based on his calculated floatability index, should decrease in the order clarain, vitrain, fusain and durain; while Horsley and Smith 13 indicated the decrease to be: vitrain, clarain, durain and fusain. These differences can be attributed to the specific coals used in each study and to the individual macerals composing each coal type within a given coal."

Jan 1, 1989

By A. Gene Collins, Cynthia A. Pearson, Cathy J. Waters

The chemistry of selenium and tellurium is discussed , along with a method of preparing a synthetic oilfield brine , an oilfield brine sampling method , and methods for determining selenium and tellurium in complex oilfield brines . Selenium either can be reduced to the elemental form with sulfur dioxide and determined semiquantitatively by color comparison of the red amorphous form or can be converted to selenite and determined quantitatively by reacting it with 3,3 ' - diaminobenzidine and obtaining its spectral absorbance at 420 mu . Tellurium can be reduced to the elemental form with hypophosphorous acid , and the spectral absorbance of its red hydrosol can be measured at 400 mu . Less than 0.05 mg / 1 of selenium and 0.1 mg / 1 of tellurium can be determined by the described methods .

Jan 1, 1964

By Lars Osen

The Bureau of Mines investigated (1) the effect of torsion on yield and ultimate strengths of bolts when the torsion is applied first and tensile load is applied independently of torsion and (2) various methods of increasing the tension-torque ratio and/or narrowing the data spread of the tension-torque relationship. A special torsional attachment was fabricated to attach to a universal testing machine to independently subject rock bolts to combined tensile and torsional loads. It was found that initially installed torsion is nullified during tensile loading and the tensile yield and ultimate strengths are not significantly reduced. Lubricating various components of a bolt assembly or using hardened washers will improve the tension-torque relationship during conventional installation; however, the torsional load is not nullified during this type of loading. Hence, a bolt is subjected to a combined stress throughout the loading cycle; the yield point will thus be lowered compared with the pure tensile yield if care is not taken during installation to stay below the torsional yield.

Jan 1, 1966