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By Martin J. Gavin

The results of investigations of the oil-shale resources of the United States were first published by the United States Geological Survey in 1915.1 Other reports 2 have followed. These reports, investigations by private individuals and corporations, and the beginning of the development of an oil-shale industry in this country have aroused considerable interest in the possibilities of these shales as a commercial source of hydrocarbon oils. The Bu- . reau of Mines bas appreciated these possibilities, and since 1916 one or more of its engineers have given all or part of their time to investigations relating to the treatment of oil shales. A short pamphlet a containing general information on the possibilities of oil shale in this country, particularly the shales of the Rocky Mountain district, has already been published. This pamphlet gives methods for assaying the shales of oil and ammonia and contains a bibliography for the use of those desiring to search the literature.

Jan 1, 1924

By D. Pickering, R. Wharton

The deadline for meeting legal requirements relating to the sale of explosives in the European Union was 1 January 2003. The paper examines the range of materials that have already been certified by the different Explosives Notified Bodies as well as recent national and European Commission decisions relating to this work. The implications of enlargement of the European Union are also discussed as is the future role of the Great Britain Explosives Notified Body in certification and assessment.

Jan 1, 2003

By Joseph M. Pugliese

This work was done by the Bureau of Mines to provide quarry operators with an uncomplicated, first-approximation method for designing blast patterns, considering geologic structure, and to show the valid use of the technique by comparing drill and blast pattern dimensions used in the quarry with those determined by the presented method. The author visited 12 limestone and dolomite quarries in Ohio (Adam, Crawford, and Highland Counties), Wisconsin (Milwaukee, Racine, and Waukesha Counties), and Minnesota (Fillmore, Olmsted, and Wabasha Counties); observed the blasting practices; studied the major geologic features; and after discussion with the quarry managers, foremen, and blasters, compared the quarry blasting patterns with those as calculated by the empirical formulas (after R. L. Ash), with geologic structural considerations. When geologic structure such as bedding, jointing, folding, and caves, as well as explosive properties and field performance characteristics are accounted for in a manner suggested by the research, the presented empirical formulas may be used as a good first approximation. The included steps in planning a blast design and generalized blast patterns should be of help to the quarry operator. Design changes are recommended for those quarries where problems are occurring.

Jan 1, 1972

By R. G. McLusky

This paper analyzes the opinion in Bragg v. Robertson, 72 F.Supp. 2d 642 (S.D. W.Va. 1999), a case which threatens the future of surface mining in West Virginia and which will almost certainly result in new policies or rules that will affect surface mining everywhere. This paper addresses: (1) the jurisdictional bases of the action which relies on the federal surface mining laws to enforce a state mining program; (2) settlement agreements reached in the case that threaten to alter federal policies beyond West Virginia borders; (3) a programmatic environmental impact statement on mountaintop mining being undertaken by the federal government; and (4) an opinion by the Court outlawing excess spoil disposal in intermittent and perennial streams.

Jan 1, 2001

By J. W. Hawkins, K. B. C. Brady, K. Miller, J. Cuddeback

Remining of abandoned coal mines in Pennsylvania requires the implementation of pollution abatement and mining techniques called Best Management Practices (BMPs). Water-quality data from over 100 remining sites with more than 230 abandoned discharges were analyzed with respect to the types of BMPs employed to abate the pollution loadings of acidity, iron, manganese, aluminum and sulfate. Discharges exhibiting a significant decrease in acidity were most highly associated with sites where large volumes of alkaline materials were encountered (66.7%) or added (63.7%). The best results for iron loading were achieved with large-quantity alkaline addition (54.6%) and water handling systems (47.8%). Water handling systems (47.4%), daylighting (40.7%), and revegetation (40.2%) were associated with significantly lower manganese loadings. The decreases in acidity and sulfate loads associated with increasing the amount of alkaline material in the backfill indicates that the production of acid mine drainage can be retarded by adding large quantities of alkaline materials.

Jan 1, 2002

By J Deen, P Sterk, W Forsyth

Homestake Mining Company has made a firm commitment to develop a functional and cost effective perimeter blasting program. The goal of the program is to develop smooth, sound walls in all development ends. A good perimeter blasting method will improve safety, reduce waste rock handling, allow easier support installation and reduce scaling time. All the benefits will contribute to an overall reduction in total development costs.

Jan 1, 1997

Jan 1, 1997

By C. Navalkar

Systematic drilling & blasting techniques are currently being viewed in the mining & construction industry as a correct 8z scientific approach for optimization process in rock excavation, as drill & blast costs usually represent major share in total cost of production and also the environmental impacts plays an important role in designing of the operations. Designing a blast is a complex planning task, which for optimization, includes deciding the bench geometry with respect to the rock properties & geology of the area, capacity of the excavators, choice of explosives & detonation method, tiring sequence, etc. Optimization of blast design needs a detailed comprehensive study of all the above intersecting elements. Preblast & Post blast surveys are required for further improvements in blast designs. However, the choice of blast design depends upon the the requisite blasting results opted for and the cost you are ready to pay for the same. The blasting operation, in general, also involves numerous side effects namely, ground vibrations, fly rocks, dust, noise & gas pollution, air blast effect etc. Again these effects can be made tolerable up to a certain extent depending upon the limitations of the environmental obligations as may be specified by the concerned authorities.

Jan 1, 2001

Lime-enhanced carbothermic reduction may provide an alternative process for treating low grade chalcopyrite concentrates. To date, most research on lime-enhanced reduction has been on pure, synthetic sulfides. In this study, preliminary experiments were carried out on natural chalcopyrite using a thermal analysis system to assess the rate and extent of reaction at several temperatures and identify the major solid and gaseous reaction products. Calculations were performed to establish the thermodynamic limits of the reactions in the temperature range of interest in order to identify the potential conditions for processing chalcopyrite concentrate. The study found that finely ground chalcopyrite can be reduced carbothermically in the presence of lime at moderate temperatures and in a reasonable time to form metallic copper, with the sulphur reporting virtually entirely to calcium sulfide. At temperatures below about 750?770ºC calcium ferrite is the stable form of iron whereas at higher temperatures metallic iron is stable. Further work is required to demonstrate the reaction on a scale to obtain sufficient sample for evaluation of subsequent processing steps to remove the gangue material and iron products from the copper.

Jan 1, 2009

By D. Tao

The reverse cationic flotation is the most widely utilized flotation method for concentrating iron ore. In such a process quartz is often floated with ether amines (R?O(CH2)3?NH2) partially neutralized with acetic acid. However, it is well known that the cationic flotation of hematite does not work well if a certain amount of slime is present in ore slurry. To improve flotation performance, starch is often added to the flotation feed to selectively flocculate and depress the iron minerals and sodium silicate is used to disperse the silica gangue. The present study was conducted to improve the flotation efficiency of iron ore flotation by use of a new type of depressant for clay and iron minerals, i.e., GP clay binder. It is postulated that the GP clay binder minimizes slime adsorption on quartz and hematite particles by agglomerating clay particles to reduce their surface area. It is further theorized that the clay binder helps depress hematite flotation due to its unique chelating ability to iron ion. The results from this study clearly show that the GP clay binder is an effective depressant in iron ore flotation. When it was used as a substitute for corn starch, it increased concentrate grade from 60.78% to 67.67% and increased iron recovery from 71.96% to 72.90%. The combined use of GP clay binder with corn starch produced even better flotation performance, increasing concentrate grade to 67.08% and iron recovery to 78.15% simultaneously. Key words: Clay Binder; Depressant; Iron Ore; Flotation.

Jan 1, 2009

To build an effective entry roof beam, a roof bolting or supporting system must be of the ability of providing a clamping force to the bolted roof strata. Currently, two roof bolting systems are widely used to serve the purpose of providing such a clamping force. They are resin and mechanical anchorage bolting systems. Both numerical modeling and double shear testing results indicate that a greater pre-installed load or pretension of a roof bolting system is very critical for effective beam building. Although it?s generally accepted that a mechanical anchorage bolting system can provide a greater pretension than a resin anchorage bolting system does (Su and Poland, 2007 and Peng, 2008), no published field data are available to support such a conclusion. This paper analyzes the results of our field tests on both roof bolting systems, explains why one roof bolting system is better than the other under a typical roof condition, and finally discusses the effective means for coal mine operators to determine the best roof bolting system for their roof conditions.

Jan 1, 2011

By Daryl R. Tweeton

This Bureau of Mines publication provides information to assist in selecting a lixiviant (leach solution) for in situ uranium leaching. The cost, advantages, and disadvantages of lixiviants currently used and proposed are presented. Laboratory and field tests are described, and applications of geochemical models are discussed. Environmental, economic, and technical factors should all be considered. Satisfying environmental regulations on restoring groundwater quality is becoming an overriding factor, favoring sodium bicarbonate or dissolved carbon dioxide over ammonium carbonate. The cheapest lixiviant is dissolved carbon dioxide, but it is not effective in all deposits. Technical factors include clay swelling by sodium, acid consumption by calcite, and the low solubility of oxygen in shallow deposits. Laboratory leaching tests can provide useful data. However, they can be misleading if, for example, the ore is allowed to oxidize before testing or if distilled water instead of formation water is used for making solutions for permeability tests. Geochemical models presently are more useful for indicating trends in solubility than in reliably predicting concentrations.

Jan 1, 1981

By Gerald C. Dohm

INTRODUCTION After a mining company has discovered a mineral deposit, the problem is then how to mine and process that deposit the best way. The principal problem facing managers or engineers who must decide on mine plant size, equipment selection, and long-range scheduling is how one can optimize a property not only in terms of efficiency but also as to project duration. Mine opti¬mization is dependent upon the interaction of con¬tributing parameters which leads to maximizing the net present value (NPV) Realistic mine planning is the key, to the analysis. The process is to be used when evaluating undeveloped properties or when a complete revamping of existing facilities is scheduled The proc¬ess is not intended for detailed mine design but rather for property evaluation and feasibility studies. The derivation of the various input parameters will only be discussed to the point where a meaningful correlation can be made with the overall analysis. The interrelationship of the parameters will be the central point because most company guidelines and financial analysts have their own standards when deriving the various inputs. Assume that the data is totally acceptable and pro¬vides at least the following categories of information and guidelines- (1) mineral and waste inventory; (2) geologic, hydrologic, and geotechnical criteria; (3) topographic layout including property boundaries; (4) metallurgical flowsheet, recovery and design criteria; (5) access, water, power, and environmental base-line study; and (6) financial constraints (minimum rate of return, payback period, etc).

Jan 1, 1979

By Neyer David Cerna Flores

El desarrollo de proyectos mineros en espacios geográficos con históricos pasivos ambientales conlleva en la población un imaginario de contaminación extrema y consecuencias graves para la salud y el deterioro de su hábitat presente trabajo. Es este contexto Antamina desarrolla mecanismos alternativos para el manejo de los conflictos socioambientales de su entorno, los cuales buscan generar confianza entre las partes, disminuir los conflictos socioambientales y explorar conjuntamente propuestas de crecimiento y desarrollo sostenible. Por ello, el presente trabajo describe la experiencia realiza, donde los mecanismos utilizadoss basan su accionar en la atención de las preocupaciones, necesidades, intereses y concepciones de los grupos de interés sobre el desempeño ambiental de Antamina.

Sep 9, 2007

For the benefit of those of our members who are considerable holders of securities,but owing to their isolated situations are not in close touch with the metropolitan market and current quotations, we are publishing two very interesting graphs, showing the course of the bond and stock markets in New York over a long period. These graphs are furnished through the courtesy of the financial department of the New York Tribune.

Jan 11, 1919

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

By T. Grammatikopoulos, A. McKen, O. Christiansen

Vanadium mineralization occurs in oxide-rich horizons within layered metagabbro zones of the Sinarsuk deposit, West Greenland. The main oxide minerals are vanadiferous magnetite and ilmenite, comprising 30% to 90% of the rock volume and the ratio of magnetite to ilmenite ranges from 3:2 to 4:1. Ore microscopy shows that magnetite and ilmenite vary between 0.2 mm and 4.5 mm in grain size, but locally they are coarser grained. Grains are subhedral to euhedral and annealed suggesting that they will liberate very well upon grinding. Electron microprobe analyses indicate that magnetite grains are homogeneous and have a vanadium content, in different mineralized samples, ranging from 1.93 wt% to 2.68 wt% equivalent V2O5. Ilmenite hosts abundant and variably sized hematite lamellae, and it has vanadium contents ranging from 0.32 wt% to 0.59 wt% equivalent V2O5. Preliminary beneficiation of two composite bulk samples shows the samples can be beneficiated fairly easily using low-intensity magnetic separation at a coarse grind (106 microns to 600 microns) to yield a vanadiferous magnetite concentrate. The presence of hematite lamellae in ilmenite prevents recovery of a satisfactory ilmenite concentrate. The most likely beneficiation flowsheet would encompass a primary mill (SAG or rod mill), which would grind to about 600 microns, followed by a rougher magnetic separation stage. The rougher magnetic concentrate would be reground in a ball mill until suitable liberation is achieved. The reground material would then be cleaned in further LIMS stages. However, further laboratory testing is required to establish the final beneficiation program. This work demonstrates the value of mineralogical investigation in guiding and explaining the results of beneficiation processes.

Jan 1, 2002

One of the important directions of further increase of quality and efficiency of control of mining companies and branches is the creation of the operation and development monitoring systems of such facilities. The main purpose of these systems is to provide managers with reliable and timely information on the current state and typical tendencies of operation of the facilities under control. However until the present time no scientific and methodical ground for system monitoring of the mining companies and branches has been created. Therefore, the authors of the report have aimed to assess the current situation with regard to the researches in this field and to do analysis of the most important aspects and ways of solution of the issue under consideration.

Dec 6, 2010

By S. L. Lebo, J. D. Gargulak

Lignin, the second most abundant natural polymer and bi-product of the pulp and paper industry, has been commercially available in a number of forms since 1940. This growing industry is fueled by demand in traditional applications. Reagents that offer unique solutions in various mineral process applications are examples of advanced uses that also fuel growth. These applications include flotation reagents in fluorspar, bastnäsite and potash, as well as in the zinc pressure leach process. Due to the fact that no concerted effort has been made to find applications for modified lignosulfonates, it is quite possible that this natural material will find use in other benefication processes.

Jan 1, 2002