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By E. C. Lane

For a number of years the Bureau of Mines has been studying crude petroleum from the producing fields of the United States, During the past year 10 crude-oil samples have been collected and analyzed from the producing fields of Pennsylvania and New York. This report gives the results of these analyses and for the purpose of comparison also analyses of samples of crude oils taken previously from some of these fields. This survey includes samples from normal producing properties as well as from properties using stimulative production methods such as water flooding and rapressuring. The outstanding feature of the survey is that the crude oils from tike various fields throughout this general area are similar in character and uniform in quality although they were produced from different sands and by various methods. Samples from fields in Venango County, Pa., however, appear to have a lower gasoline content than the others. This report includes two analyses reprinted from Bureau of Mines Bulletin 291.4/

Jan 1, 1938

By Richard P. Graff

Author?s note: Diversity in practice exists in the application of Generally Accepted Accounting Principles (GAAP) for purchase price allocations with respect to the recognition of Value Beyond Proven and Probable Reserves or VBPP, as defined by the Emerging Issues Task Force (EITF) in EITF 04-3: ?Mining Assets: Impairment and Business Combinations?. This diversity appears to arise from differing interpretations of what constitutes sufficient information to value components of VBPP in business combinations. Concerned with this diversity in practice, respected members of the mining community formed a working group which prepared an issues paper that discussed this diversity and provided recommendations for recognition and valuation of VBPP in business combinations. The working group then submitted this paper to the EITF, requesting further guidance be issued on the concept of VBPP. In conjunction with the submission to the EITF, the working group also provided this paper to the United States Securities and Exchange Commission (SEC) for review and comment. The EITF discussed this issue at its May, 2008 agenda committee meeting. However, it declined to add this topic to the EITF agenda for further consideration. Absent additional guidance on VBPP from the EITF, the working group submitted a proposed definition of VBPP to the U.S. Securities and Exchange Commission for its consideration. The following article, which is consistent with the issues paper that was submitted to the EITF and the SEC, discusses the components of and valuation techniques for VBPP. The correspondence with the U.S. Securities and Exchange Commission, which includes the proposed definition of VBPP by the working group, is attached as Appendix 1 to this article.

Jan 1, 2008

By Franz Walchshofer, Mark Kuchta, Nobuharu Isago, Ugur Ozbay, Wolfgang Dolsak

A series of in situ pull test were performed on a new design friction stabilizer bolt with the objective of determining its performance characteristics. The bolt is installed while drilling, thus improving safety and significantly reducing the installation time. An optional expansion element can be inserted into the bolt to provide an end-anchorage, which further increases the bolt’s capacity. In situ tests show that the pull capacity of the 2 m long new design bolt is about 15 tons. When installed with an expansion element, the pull capacity of these bolts becomes as high as 30 tons.

Jan 1, 2005

By T. Proietti, L. Mongiovì, L. Simeoni

Reliable estimates of the kinematic characteristics of movements are obtained by using a statistical model SSM. This model represents a useful tool for the management of alert and alarm systems. L'élaboration des données du déplacement médian d'un modèle statistique SSM opportun fournit des estimations fiables des caractéristiques cinématiques du mouvement. Le modèle peut être ainsi utilisé pour la gestion des systèmes d'alarme. Die Bearbeitung von Bewegungsdaten anhand eines geeigneten statistischen Modell SSM ergibt vertrauliche Abschätzungen der kinematischen Eigenschaften der Bewegung. Das Modell kann also für das Management von Alarmsystemen verwendet werden.

Jan 1, 2003

By William E. Eckard

Production of oil from a narrow shoestring sand presents problems unique in the oil industry. Especially important, from both an engineering end an economic standpoint, are the limitations imposed upon well patterns and spacings by the shape of the field. This report concerns a study of the Paola shoestring, Miami and Franklin Counties, Kane., where well density of 0.85 acre per well was not uncommon to insure profitable primary recovery in a reasonable time. However, such a great number of wells increased the operator's investment and reduced his profit considerably. It was the purpose of this study to investigate various well patterns and spacings applicable to water-flooding a shoestring reservoir and the effect of these factors upon recovery of oil and the most profitable operation of the pool. The designer of well patterns for a shoestring sand should evaluate carefully the edges of the shoestring, even though they may be considered too thin to drill. These comparatively thin edges contain large quantities of recoverable oil; moreover they are resaturated with oil as the pool is water-flooded.

Jan 1, 1951

By Woodcock J. T, Zhu T, Sparrow G. J

A lead-zinc-pyrite flotation middling was pressure oxidised to give residues containing iron hydroxy sulphates (a mixture of basic iron sulphate (BIS) and a hydrated iron sulphate (HIS)) and lead sulphate. Direct thiourea leaching of this residue gave over 90 per cent extraction of gold and silver, but thiourea consumption was high (56 kg/t) because of soluble iron(M) in the residue. Attempts were made to decrease the thiourea consumption by removing the water-soluble iron(M) or reducing it to iron(II). Water washing of the pressure oxidation residue removed most of the hydrated iron sulphate but little of the basic iron sulphate. Iron removal was only 12-20 per cent, depending on the number of washes, from one sample which was low in HIS, and 40-45 per cent in another which was high in HIS. Iron extraction was not appreciably increased by using dilute sulphuric acid (with or without additions of sodium sulphite), dilute phosphoric acid, or sodium chloride solution (150 g/L NaCI). Direct thiourea leaching of the water-washed residue gave over 90 per cent extraction of gold but only 49 per cent of silver, with a thiourea consumption of 27 kg/t. However, the application of a water wash followed by reduction of dissolved iron(III) with sodium sulphite in the presence of thiourea, and then thiourea leaching resulted in over 98 per cent extraction of gold and silver for a thiourea consumption of 26 kg/t.

Jan 1, 1991

By J P. Jona, S R. Poulson, C H. Gammons

Spatial and temporal trends in water chemistry in the acidic (pH ~2.6) Berkeley Pit lake, Butte, Montana, can be explained by a newly developed iron-cycling model. Key elements of this model include: subaqueous oxidation of pyrite and other metal sulfide minerals by dissolved ferric iron, producing Fe2+ as a by-product; re-oxidation of Fe2+ to Fe3+ in the epilimnion, assisted by A ferrooxidans; precipitation of secondary ferric minerals (schwertmannite, jarosite) in the epilimnion; and replenishment of the Fe3+ concentration of the hypolimnion by seasonal lake turnover and gravitational settling and re-dissolution of ferric precipitates. Pyrite oxidation rates were approximated by using published rate laws and information on the Fe3+ concentrations (~5 mmol) of the Berkeley Pit as a function of depth. The results indicate that subaqueous pyrite oxidation may be releasing as little as 6 + 106 or as much as 600 + 106 moles of H+ each year to the lake; the large range reflects uncertainty in calculation of the specific surface area of pyrite in the flooded pit. This helps to explain the observation that the pH and metal concentrations of the Berkeley Pit have not improved with time since mine flooding began in 1983. Vertical cycling of ferric iron in the pit lake permits pyrite oxidation to continue in deep water, even in the absence of dissolved oxygen. This hypothesis is supported by preliminary stable-isotope data.

Jan 1, 2003

By Thomas K. Matson

The coal reserve base in the Western United States is presented for coalbeds amenable to extraction by underground mining methods. The Federal Bureau of Mines has abstracted data on the quality and quantity of coal resources/reserves from numerous State and Federal publications and modified such data as necessary to allow computer storage and retrieval. Tonnages are compiled by State, county, coalbed, and rank, and allotted to sulfur categories by statistical apportionment. The coal reserve base in those States west of the Mississippi River, amenable to underground mining, is estimated to be approximately 131 billion tons. Of this total, about 30.8 billion tons are bituminous coal, 100.2 billion tons are subbituminous coal, and 126.4 million tons are anthracite. Lignite is not considered for underground mining in this report. Included in this report is a glossary of terms applicable to a classification system for coal resources and reserves as jointly defined by the Bureau of Mines and U.S. Geological Survey. The purpose of this system is to provide for direct comparison or compilation of various resource/reserve data.

Jan 1, 1975

By R. S. Fowkes

Jetstream pressure distributions and coal cutting rates were determined for a number of nozzles and under different operating conditions. The jetstrearn pressure distribution data were fitted to an assumed curvilinear equation by the utilization of a numerical least-squares technique with the aid of a digital computer. Subsequent manipulation of the approximation equation showed that the total force of the jetstream, rather than its maximum pressure or total kinetic energy per unit Lime, was the most significant quantity affecting the coal cutting rate. A shorter method for assessing the ability of a nozzle to cut coal was found.

Jan 1, 1968

By D. R. Spears

As part of its mission to develop technology to assure a continuing supply of minerals, the US Bureau of Mines has investigated the flocculation of a Stillwater, MT, chromite ore. The ore was flocculated at different solids contents and at different stirring speeds to determine the importance and effect of hydrodynamic factors. In acidic and basic pH, the chromite ore was flocculated with high molecular weight polyacrylamides differing in the degree of hydrolysis. Polyacrylamides were found to bind to chromite ore particles through hydrogen bonding. The anionicity of the polymer and the pH affected the degree of polymer-particle interaction, which in turn affected polymer conformation at the surface. A polymer conformation with many loops and tails was used to explain high flocculation efficiency. It was found that such a conformation could compensate for poor hydrodynamic conditions.

Jan 1, 1992

By D. A. Cormode

"INTRODUCTIONPine Point Mines, operated by Cominco Ltd., is located approximately 55 miles east of Hay River, N.W.T. by the southern shore of Great Slave Lake.The milling operation commenced in the fall of 1965 at a design capacity of 5,000 tpd. An addition which came on stream late in 1968 raised the nominal capacity to 8,000 tpd. Currently the milling rate is 11,000 tpd.The lead and zinc sulphides occur in dolomite host rock. Typical feed grades at present are 2% lead, 5.5% zinc and 5 % iron. When dolomite is present even in relatively minor amounts in the zinc concentrate, it presents serious treatment problems and causes inefficient operation of electrolytic zinc refineries.By 1972, it had become apparent that magnesium rejection in the form of dolomite was deteriorating because of increased plant throughput of less amenable ore. This paper will briefly outline the Pine Point zinc flotation circuit and will discuss the two phase program for reducing the magnesium level in the zinc concentrate. The program included changes and alterations to the flotation circuit and the construction of an acid leaching plant."

Jan 1, 1977

In 2001, 14,623 mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). This was an increase of 210 mining operations compared to 2000. Almost half (49%) were sand and gravel mines, followed by stone (29%), coal (15%), nonmetal mines (5%), and metal mines (2%).

May 1, 2003

By H. R. Babitzke

To develop alloys suitable for use at elevated temperatures, columbium and tantalum were combined with tungsten, hafnium, vanadium, zirconium, and titanium, and the resulting alloys were evaluated with respect to fabricability, hardness, Electrical resistivity, strength at elevated temperatures, oxidation resistance, and bend transition. Of the 23 compositions tested, Cb-2OHf-5W-10Ti exhibited superior high-temperature properties. A recrystallized sample of this alloy was fabricable at room temperature, had a strength of 44,000 psi at 1,200° C, and had an oxidation rate of only 7.7 mg/cm2/hr at 1,000° C.

Jan 1, 1966

The Bureau of Mines Minerals Information organization collects worldwide data on virtually every commercially important non fuel mineral commodity. These data form the base for tracking and assessing the health of the minerals sector of the U.S. economy. This data collection activity was instituted by the 47th Congress in an appropriations act of August 7, 1882 (22 Stat. 829), to place the collection of mineral statistics on an annual basis. The most recent authority for the Bureau of Mines Minerals Information activity is the National Materials and Minerals Policy, Research and Development Act of 1980 (Public Law 96-479, 96th Congress), which strengthens protection for proprietary data provided to the U.S. Department of the Interior by persons or firms engaged in any phase of mineral or mineral-material production or consumption.

Jan 1, 1984

Research 86 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information 2401 E Street, NW., Washington, DC 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1986

By Charles Will Wright

The purpose of this paper is to present briefly certain preliminary results of the study of mining methods by the United States Bureau of Mines; to show the relative importance of each method in terms of tonnages mined and man-hours consumed; to give to the mining engineers and particularly to the young student of mining a better understanding of the principal mining methods; and to indicate changes now in progress and to present suggestions for improvements in the art of mining. Questions of mine development and details of underground practice such as drilling and blasting, loading, hauling, hoisting, ventilating, pay systems and mine management are omitted, as these have been or will be discussed in other bureau publications.

Jan 1, 1931

By James A. Finch, Stéphanie Gélinas

"A colorimetric technique, originally developed for methyl iso butyl carbinol (MIBC) based on the Komarowsky reaction, has been extended to a wide range of common mineral flotation frothers. The procedure, which is briefly described, is shown suited to on-site determination in a series of industrial campaigns. Some frother observations are described, including: concentration evolution down a bank, distribution between pulp and froth phases, and a mass balance around a circuit. Minute amounts of frother in recycle water were also measured.The contribution of frother and alcohol by-products in the analysis was generally additive for plants using aliphatic alcohol type frothers and decoupled for systems using glycols. Typically, U250C (polyglycol) was used at higher concentration (>10 ppm) than MIBC (aliphatic alcohol) (<10 ppm) or F-150 (polyglycol) (<3ppm).The ability to monitor frother easily will help interpret gas dispersion behaviour and should permit further optimization of flotation cell hydrodynamics and chemistry. The capability to directly measure should help optimize the type, amount and location of frother addition, and to assess frother recycled with reclaim process water.INTRODUCTIONOwing to the lack of analytical methods, the task of determining frother concentration in plant flotation circuits is not routinely performed. Industrial sites seldom outsource analyses that are both costly and inconvenient, due to the necessity of shipping freeze-dried samples to remote testing facilities. A more direct colorimetric method has recently been demonstrated for the laboratory characterization of common industrial frothers (Gélinas and Finch, 2004). The approach, based on the Komarowsky reaction (Penniman et al., 1936; Coles et al., 1942; Duke, 1947), was previously described by Parkhomovski et al. (1976) for methyl iso butyl carbinol (MIBC). The reaction involves the interaction of the OH group of a higher alcohol, concentrated sulphuric acid, and salicylaldehyde, to yield coloured solutions with intensities that can be analyzed by UV-visible spectrophotometry."

Jan 1, 2007

By S. C. Sun

Pennsylvania has ample reserves of high-alumina clays which are potential sources of alumina, but many of these clays contain large amounts of iron, which makes them unsuitable for treatment by acid processes(1). The purpose of this investigation was to determine the optimum conditions for the selective hydrochloric acid leaching of iron (2-4) prior to the sulfuric acid extraction of alumina from Pennsylvania ferruginous high-alumina clays. This was accomplished by first testing the iron-bearing minerals and the clay minerals most often encountered in Pennsylvania clays to determine their rate of dissolution in hydrochloric acid solutions. The results of individual minerals were then based for leaching Pennsylvania clays with a 19% hydrochloric acid solution at the boiling point of the acid for approximately 30 minutes to achieve as high as 90% iron removal and only 2-5% alumina losses.

Jan 1, 1968

By W. Dziurzynski, S. Nawrat, A. Krach

The paper presents research on the influence of the goaf methane inflow on a fire. The problem was investigated by a computer simulation of a fire developing in a goaf. A relevant mathematical model of the fire was selected, which considered both burning of coal and methane. The combustion process is very sensitive on the oxygen and methane concentrations, which was indicated on graphs of the fire temperature evolution. Examples of computer simulation for various location of the fire were considerd. Analysys of results confirms the influence of the content of the goaf methane on development of fires.

Jan 1, 2003

By Ali Kazmi, Wern-ping N. Chen

A load rating procedure was performed to evaluate safe load capacity of the Port of Miami Tunnel (POMT), FDOT Tunnel No. 871071 SR 887. The rating procedure performed on a total of eleven stations beneath roadways and with fill depth less than the tunnel exterior diameter (42 ft). Calculations on tunnel sections passing beneath roadways were performed to evaluate the structural response of the sections subject to moving vehicular loads, dead load, and earth pressures. Ratings were performed in accordance with AASHTO and FDOT guidelines. The procedure considered two types of vehicles (HL-93 and FL-120) and two rating levels (Design level and Permit level). As part of HL-93 vehicle, Tandem load was also considered for rating, separately. For HL-93 and HL-93 Tandem, inventory and operating level ratings were performed. The results show rating factors are high. The minimum rating factor is 16.8 using Inventory truck HL-93. For Permit level using FDOT FL-120 truck the minimum rating factor is 6.9. As can be seen, rating factors are higher than comparable analysis for bridges. This paper explains how the procedure can be implemented for tunnels and evaluates the rating results.

Dec 1, 2022