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By Robert M. Miller, Judy Milligan

A computerized "Decision Support System" was used to evaluate an "Underground Platform Approach to Oil Recovery". Over a billion calculations were required to model the mine layouts; learning curves for shaft, tunnel, and well drilling scenarios; detailed cost, schedule, and resource data; complex oil production and material balance data; varying reservoir parameters; and complex oil pricing curves. Simplified "optimum" solutions were defined in terms of muck hoisting capacity, barrels of oil per day, and present worth. Complex "optimum" solutions were defined in terms of minimal exposure scenarios during development followed by shortest time to full production.

Jan 1, 1987

By David A. Smith

A new generation of reliable, stable, and easy to use bulk emulsions allowing application in tunneling and drift rounds has been developed. This new product group of bulk emulsions has been especially formulated for use in small-diameter holes and is a significant advancement in bulk emulsion technology. Reliable and easy-to-use bulk delivery equipment has been designed and developed to allow bulk emulsions to be used in a wide variety of shaft and tunneling applications.

Jan 1, 1987

By B. Law, M. Menabde, B. Baird

Blasor is a new mine planning tool which is being used in the long and medium-term optimization of multi-open-pit operations throughout BHP Billiton’s Base Metals and bulk commodities portfolio. It is not just a scheduler, nor even only a schedule optimizer—although this function lies at the heart of the tool’s functionality—but a pit development plan optimizer, used from ultimate pit design and process plant capacity sizing right through to mining phase design and optimal panel scheduling. The tool uses a mixed-integer-linear-programming optimization engine to determine when material should be excavated and where it should be sent to optimize discounted operating cash flow over the life of operation. The core software design concept of Blasor is to provide a tool which is intuitive and flexible enough so that a competent mine planner can perform a pit development plan optimization without assistance from optimization specialists. To this end, a generalized graphical user interface has been implemented which allows full configuration of the optimization problem, including the definition of all inputs and constraints, specification of the material flow topology, bin and destination class definitions and full specification of the economic model encompassing prices and costs. This paper describes the capability of Blasor and outlines the design concepts underlying its design philosophy.

Jan 1, 2007

Coal, America's most abundant fossil fuel, is expected to play a key role in our pursuit of energy independence. A substantial increase in coal exploitation will be required if we are to fulfill our future energy needs. It is essential that new developments continue if stable coal prices are to be achieved and maintained. The challenge of the mining industry is to continue these developments in the face of problems related to increasing labor costs, inflation and environmental restoration. With expectations of increased activity in surface coal mining, the U.S. Bureau of Mines has authorized this study to determine the preliminary economic and technologic feasibility of underspoil haulage in area strip coal mines and to identify geologic and geographic areas where such a system could be used. These objectives were met by literature search, data-gathering visits to several active area strip mines and by analyzing various haulage systems that were superimposed on three model mines. Potential advantages of such a system include: 1) improved mine design; 2) lower mine operating costs; 3) improved land reclamation; 4) lower manpower requirements; 5) lower mobile equipment requirements; and 6) smaller, less sophisticated maintenance facilities.

Jan 1, 1975

By Slobodan Radosavljevic

The polymetallic W-Pb-Bi-Ag ore from the ?Nova jama? ore zone of the Rudnik ore field have been investigated. Contact-pneumatolytic (skarn), pneumatolytic-hydrothermal, and hydrothermal mineralization phases are defined in this ore zone. The most significant mineralization phase that gave compact ore bodies is pneumatolytic-hydrothermal phase. A relatively pure Mo-free scheelite is the only tungsten-bearing mineral. Lead minerals are mostly presented by Pb-Bi sulphosalts and much less with galena. The image analysis coupled with Energy Dispersive Spectrometry (EDS) analysis on a Scanning Electron Microscope (SEM) was applied to the characterization of a W-Pb-Bi-Ag ore as an efficient tool for mineral quantification. Results of EDS (Energy Dispersive Spectrometry) analyses gave the empirical formulae: Pb1.91Ag0.05Cu0.08Bi1.93S5 for cosalite, Pb0.98Ag0.03Cu0.05Bi1.99S4 for galenobismutite and galena Pb0.99Ag0.03S.

Jan 1, 2006

By Euzebio De Oliveira

ONE of a recent batch of samples from the Serra da Baliza, in the state of Parana, Brazil, contained asphalt and a dark heavy oil; and workmen on the railway from Porto União to Uruguay discovered asphalt, coming from eruptives that outcrop along the Rio de Peixe. The occurrence f asphalt in the triassic eruptives of southern Brazil, however, has been known a long time, according to Dr. Gonzaga de Campos. It is generally believed that the Botacatú sandstone is always a hard vitrified rock, from the metamorphic action f. the overflowing eruptive contacts. In this region, however, the contact metamorphism is almost nil; the sandstone is slightly hardened in a narrow zone about 20 to 30 cm. wide. In many places, the sandstone is so friable as to be easily reduced to sand, which is used-.in, mortar for building in Guara-puava and Palmas. South and west from Porto União,. this bench of sandstone is about. 50 m. thick, and is capped by a heavy bed. f basic eruptives, many of which are amygdaloids. Dr. Geo: P. Merrill, after studying the triassic eruptives collected by the Coal Commission, reached the conclusion that. "All these rocks are of typical basalt-diabases, not in any essential different other than in structure. An interesting mineralogical phase is its paucity in olivine, which in many cases is completely lacking. Professor Hussak, who carefully studied these rocks and their accessory minerals, decided that in the dikes they are granular (diabase) and, that in the lava sheets, porphyritic (augite-porphyrite or melaphyre), and that the latter pass evidently to normal diabases and are always typical of effusive rocks. The examination f many slides from dikes and sheets leads us to adopt the opinion of Professor Hussak; the rocks of the dikes are of ophitic structure, while that of the sheets show a great variety f structure and may vary from almost granular to basaltic. The great paucity in olivine had been noted by Hussak, who classes as melaphyres, the porphyritic triassic rocks in Brazil which contain olivine.

Jan 4, 1921

By Walter O. Snelling

Discussion of the paper of WALTER 0. SNELLING, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 100, April, 1915, pp. 695 to 704. A. C. McLAUGHLIN, San Francisco, Cal.-It seems to me that Mr. Snelling's work, if it is what it appears to be, is one of the most important contributions to petroleum technology that has been brought out iii the last 25 years. If his end products are what they seem to be, he has made a discovery, which, in my judgment, will revolutionize the petroleum industry. As to industrially carrying out these processes I do not think there is the slightest difficulty, for I have had some work recently where crude oils were handled successfully at a temperature of 750°F. and pressure of 750 lb. per square inch. WILLIAM A. WILLIAMS, San Francisco, Cal.-What metal did you use, Mr. McLaughlin? - A. C. McLAUGHLIN.-Ordinary seamless tubing, extra strong. WILLIAM A. WILLIAMS.-Tests were made in Dr. Rittman's experimental plant at Pittsburgh, upon samples of residuum furnished by Mr. Bell, the residuum being the remainder of the crude oil after the lighter fractions had been removed. After the material had been run through Dr. Rittman's plant, yields of from 43 to 58 per cent. of material, boiling under 150°C. were obtained. The distillate had a peculiar odor, due to the presence of benzene, toluene, and other unsaturated hydrocarbons. W. N. BEST, New York, N. Y.-What is the difference between the Rittman and the Snelling process or system? WILLIAM A. WILLIAMs.-The fundamental difference is that reactions take place under relatively higher temperatures and pressures and with none of the oil present in its original or liquid state, while the reactions secured by Mr. Snelling and other investigators have been from the liquids in the presence of some vapors. Under such conditions as Mr. Snelling operates, the temperatures and pressures used are limited and the flexibility in the control of these variables is extremely limited when compared with the Rittman process.

Jan 1, 1916

By M. W. Robotham, H Wang

removal efficiency is analysed from a stochastic

Apr 1, 1995

By Steve Dillingham

Change occurs all of the time. In fact, it’s fair to say that change is a constant. Sometimes the change is inconsequential, but sometimes the change impacts us d i rectly and severely. Take regulations, for instance. Complying with regulatory requirements is just part of the job for those involved with explosives. But in recent years, it seems as if new or revised regulations in areas such as hazardous materials training, drug and alcohol testing, security issues, or local licensing/permitting standards are changing the way we operate on a recurring basis. Simply keeping track of all of these regulations has become a full-time job.

Jan 1, 2003

By Thomas J. Peters

A mineral survey of the Sill Hill RARE II area (No. 5304), covering 5,200 acres (2,100 ha) of the Cleveland National Forest, San Diego County, California, was conducted by the U.S. Bureau of Mines and the U.S. Geological Survey. This survey was in conformance with the Resource Planning Act (RPA) of 1974, as amended by the National Forest Management Act of 1976, to provide mineral resource information for study area classification. Bureau of Mines personnel made an economic appraisal of mineral deposits by searching pertinent geological and mining publications as well as U.S. Bureau of Land Management, U.S. Forest Service, and U.S. Bureau of Mines files and records. Known mines, prospects, and mineralized localities were examined during 1981, and sampling and mapping were done where warranted. The Geological Survey 'did geologic mapping, geochemical sampling, and geophysical surveys to aid this study.

Jan 1, 1983

By P. A. Croce

A total of 17 mine gallery fire tests (23 including sub-tests) were completed during this report period (10/1/76 - 11/30/77), directed at identifying a hazardous timber-set fuel-loading in a mine passageway that is otherwise free of combustibles. Results of these initial tests show that the capability of a particular fuel loading for propagating a fire is dependent upon the imposed ventilation air velocity and the ignition intensity, although this dependency needs to be better defined. It is also apparent that care must be taken when relating gallery test fire behavior to actual mine fire behavior, because of the restrictive length of the gallery. Present data indicate that some modification to the instrumentation scheme may be advantageous before proceeding with future tests.

Jan 1, 1978

By David L. Veith

This Bureau of Mines bibliography of U.S. and Canadian literature pertaining to revegetating coal-mined lands contains 805 references published from 1977 to 1984. Each reference is evaluated by keywords, providing the reader with a means of rapidly sorting through the references to locate only those dealing with the coal mining region and subject of interest. All references are annotated. Other sources of information are given, including Office of Surface Mining (OSM) and State reclamation agencies and other published bibliographies.

Jan 1, 1985

By John P. Hansen

Batches of red or brown iron ore concentrates, weighing 100 or 200 grams, were reduced with gaseous reductants in a laboratory-sized fluidized-bed reactor. Using a loss of weight technique, the rates of reduction were measured and the effects of temperature, gas consumption, and gas flow rates were determined. Below about 725° C the rate of reduction was controlled by the chemical reaction at the reduction interface having an activation energy of about 10 kcal/g mole. Above about 725° C the rate of reduction appeared to be controlled by the flow of the gaseous reductant and therefore to be directly proportional to the flow rate. Above 725° C, hydrogen reduced the iron ore much faster than carbon monoxide. In gas mixtures, carbon monoxide or nitrogen reduced the hydrogen partial pressure and lowered the reaction rate proportionally. When present in large concentrations, carbon monoxide had a serious inhibiting effect on the reduction rate, probably owing to carburization and sintering of the reduced iron.

Jan 1, 1970

By C. B. Manula

This report is volume 4 of at. eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment: The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation,' and ventilation. This volume of the final report describes the Roof Support subsystem of the Master Design Simulator. This model is based on popular roof support practices for different geological environments with related restrictions imposed by the Coal Mine Health and Safety Act of 1969. From geological sections, the model determines the anchor horizon for roof bolts and the density of roof support necessary. The roof support subsystem is tied to both the geology and reserves subsystem and the production subsystem of the Master Design Simulator, but can also operate as a free standing model. Several case studies are presented showing the application of the model. A detailed user's manual, including a program listing, is presented in the appendices.

Jan 1, 1974

By S. J. Duda

Procedures for detecting and locating seismic sources are adapted to the case of entrapped miners. During an emergency the entrapped miner is likely to generate seismic signals, by knocking against the walls of the shaft. With a seismic array station deployed near the disaster area, the seismic signals can be recorded. Two algorithms are presented for the location of the source from the arrival times of a seismic phase: The first algorithm produces one, most probable location, under the assumption of constant velocity of propagation of seismic waves in the medium. The second algorithm is similarly applicable, however without any restriction on the seismic velocities in the medium between the source and the array. While the first algorithm uses an analytic approach, the second one is based on a trial and error procedure. The second algorithm gives locations with arbitrarily high accuracies, depending only on the accuracy of arrival time measurements and on the compatibility of the true velocity distribution and the assumed velocity model. The algorithm is shown not to require under certain conditions direct .arrival time measurements, thus eliminating a potential source of errors in the location of entrapped miner.

Jan 1, 1973

By Charles L. Kusik

A study was conducted for the Bureau of Mines, U.S. Department of the Interior, to provide information which will lead to an increase in the recycling of mineral materials, in order to help conserve the Nation's mineral resources. Data were collected on energy requirements to recycle prompt industrial and obsolete scrap for nine metal commodities: Iron and steel, aluminum, copper, zinc, lead, stainless steel, titanium, tin, and nickel and nickel alloys. Major process routes for recycling were considered, starting from the first collection point through scrap preparation, transportation, smelting and/or refining to the molten metal, ingot, or other semi- finished form approximately equivalent to a primary metal of a similar composition. Available data for 1976 were collected on the amounts of each metal commodity recycled by major scrap categories. In addition, energy requirements were estimated for separating municipal solid wastes into four major categories: Refuse-derived fuel, and magnetic, aluminum, and glass cullet fractions. Finally, areas of research were identified to enhance recycling and/or increase the efficiency of energy use.

Jan 1, 1978

By R. L. Virta

Ball Clay -- Four companies - H.C. Spinks Clay Co. Inc. (owned by Lhoist Group), Imerys Group (formerly Kentucky-Tennessee Clay Co.), Old Hickory Clay Co. and Unimin Corp. - mined ball clay in four states during 2010. Production, based on preliminary data, was 910 kt (1.11 million st) with an estimated value of $42.9 million. That was a 10-percent increase in tonnage from 831 kt (916 million st) with a value of $37.7 million that was produced in 2009. Tennessee was the leading producer state with 61 percent of domestic production. It was followed by Texas, Mississippi and Kentucky. About 70 percent of production was airfloat, 20 percent was crude and 10 percent was water-slurried.

Jan 1, 2011

The transition from exploration to feasibility is a stage in the development of mineral resource projects that is frequently not handled well. The transition marks a point in the project development process where resource evaluation priorities change significantly from the discovery of mineralisation and the rapid assessment of the potential tenor of the mineralised system, to the detailed assessment of the deposit.   Information used in the exploration process tends to be of a qualitative or theoretical nature initially, but gradually becomes more quantitative in character as geological knowledge relating to individual prospects grows.   The transition from discovery and rapid exploration of a new deposit occurs at a relatively early stage in project development, coinciding with the first attempt to prepare a resource estimate for the deposit. Fundamental assumptions regarding both structural and grade continuity and uncertainty inherent in existing information need to be made so that they themselves may be addressed during the collection of additional data.   The effective commencement of feasibility studies involve the introduction of new accountabilities either as a result of appointment of a project manager, and through needing to be able to quantify: ò     the quality of data being collected for resource evaluation purposes; ò     confidence associated with resource estimates; and ò     the need to develop an audit trail for the project, required to make the resource evaluation decision-making process as transparent as possible.   Quality assurance is a concept to which exploration geologists have frequently had little exposure. Being able to demonstrate the quality of data used in feasibility studies is, however, a crucial component of the overall risk management and reduction.   Development of a transparent audit trail for data assists in demonstrating the quality of data which is frequently perceived to translate directly to confidence inherent in resource estimates.   Establishing procedures for geological data collection and management also provides a more reliable framework for making decisions that impact on project execution, again resulting in improved confidence in resource estimates and associated geoscientific data.   Regular, independent technical audits, in principle similar to audits conducted for the ongoing certification of standards compliant quality assurance systems, are a major, positive factor in effective project management and execution.   Information used in project evaluation, feasibility and development must be based on facts. Facts are effectively observations that are ideally made systematically, recorded in a systematic manner, and by being collected effectively are not subject to change.   Effectively managing the transition from exploration to resource evaluation, feasibility and project development involves recognising the nature of changes in the nature, detail and scope of geoscientific data required at each stage of project development. In doing so it is essential to: ò     recognise when the change occurs (as early as preparation of the initial resource estimate for a project); ò     accept that the change may not be gradual; and, ò     ensure that the project evaluation team is adequately resourced.   These objectives require recognition of the value of previous experience and the need to instill a true team approach amongst both staff and contractors associated with the project. Regular formal and informal communications between staff, contractors and other stakeholders in the project are an essential tool in ensuring personnel are aware of factors affecting their role in the project.

Jan 1, 2004

By Frank P. Frandina

The Heartland Corridor Clearance Improvement Project is part of a regional Public-Private initiative to allow double stack container trains a direct route from the Port of Norfolk through Virginia, West Virginia, Eastern Kentucky and into Central Ohio. The project involves clearance improvements to twenty-eight tunnels, twenty-one of which require structural modification. With construction of the first Package of tunnels just underway at press time, this paper summarizes the program implementation from design through the initial stages of construction.

Jan 1, 2008

By Slavoljub Makslmovic

One important element of the U.S. Bureau of Mines computer-assisted mining research program is the development of a reliable coal interface detection (CID) system. Several candidate CID concepts currently being investigated by the Bureau include use of natural gamma radiation (NGR), vibration, passive infrared, video, and radar. To help establish which CID sensor technologies need to be developed for a given seam, the Bureau has collected geological and mining practices data from over 460 underground and surface mines in the United States. Also, over 500 coal and rock samples have been obtained for laboratory analyses of ash content, sulfur content, heating value, and NGR. The Bureau's findings indicate that the immediate roof strata in 81% of the underground mines and 93% of the surface mines are made up of shale, draw slate, or claystone. The immediate floor strata in 88% of both the underground and surface mines consist of fireclay, shale, draw slate, or claystone. The results of the NGR testing indicate that the NGR method appears to be a potentially useful CID tool, provided that the immediate roof and floor are both composed of a high percentage of shale-type material.

Jan 1, 1993