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By R. W. Carn, D. Vincent

Environmental Considerations With significant increases in bulk coal movements through terminals, operators are under constant social and political pressure to reduce or remove environmental pollution problems incidental to their operations. To meet these requirements, both equipment manufacturers and terminal designers are endeavoring to design equipment and systems with stringent environmental controls. The most challenging environmental problems facing coal terminal designers and developers are terminal siting restrictions, dust control, and noise abatement. Terminal Siting Finding a suitable site can be a difficult problem because of public concern over coal dust or the impact of a terminal on the surrounding community or natural habitat of the area. Often the only suitable flat land available for terminal development is on a tidal estuary or salt water marsh with great environmental value. In many cases a period of four to six years of full environmental and social assessment has been needed. A recent example of such difficulties is the expansion at Roberts Bank, British Columbia, where environmental impact assessment studies and their public review took almost six years from initial expansion applications until the time of approval. Dust Control Modern coal terminal dust control techniques usually consist of water sprays at strategic locations to suppress dust. The application points include rail car or barge dumper, main conveyor transfers, perimeter sprays around stockpiles, stacker/reclaimer, ship-loader transfers, and loading spout. The water sprays may include a chemical wetting agent or surfactant to reduce the water requirement and increase effectiveness. Recently there have been advances with development of effective micro foam agglomerating agents. In these systems, a micro foam with very small bubble sizes is sprayed into the coal stream. The foam fills the interstices between coal particles and wets the coal fines. These systems have proven to be very effective and usually one application before stockpiling and one upon reclaiming will markedly reduce the coal dusting. Stockpile perimeter sprays can be operated either manually or at the sophisticated terminal, actuated by a computerized control system that senses key environmental conditions such as humidity, precipitation, and wind velocity. Most modern terminals collect the drainage from the stockpile area, remove the solids in settling basins, then recirculate the water to reduce water requirements and effluents from the site. Dusting of long-term storage stockpiles can be reduced by spraying the piles with chemical resin or latex binding compounds to seal the surface. These compounds also can minimize erosion of the pile by rainfall. Dust collection with air evacuation systems and cyclone or wet scrubbers can be used at key areas such as rail car dumpers, main conveyor transfers, and ship-loader spouts. The trend in dust control is away from dust collection since most dust collectors are high maintenance items requiring good operator supervision and servicing. Coal handling conveyors are usually open and uncovered. However, in areas requiring special attention they may be covered or even completely enclosed. Dust generation from terminal roads is often a significant amount of the total dust emitted from a terminal. To reduce this dusting, roadways where traffic is heavy can be paved or sprayed by water trucks. Speed limits can be enforced and use of tracked mobile equipment for stockpile handling rather than rubber-tired loaders is encouraged by authorities. Noise Abatement Terminals located close to residential areas are often faced with noise control problems. Noise can be one of the most difficult environmental problems to solve. Usually, use of electrically-powered equipment is encouraged to reduce noise levels. Rail car dumper houses can be totally enclosed to reduce both dust and noise emissions. Diesel locomotives can be fitted with special muffling devices. Green belts of trees surrounding a terminal or the ap-

Jan 7, 1983

By R. L. Derick

On a regular basis, mine personnel should obtain air samples directly from active underground areas as well as remotely from sealed locations. These samples provide mine officials with data relative to the makeup of the various atmospheres. Should conditions underground change, these results can provide a baseline that can assist officials in determining the extent of change. Relating the concentrations of individual gases to time, applying gases to equations, and examining their change over time are tools that have been successfully used to determine if a heating event exists and, if so, the extent of the emergency. These atmospheric status equations have either been developed for the mining industry or adapted from other industries. They serve as tools to assist personnel in determining the condition of underground mine atmospheres. As long as the problem area continues to be ventilated, certain gases, gas ratios, and equations can be used to determine if a fire exists, what type of material could be burning, and what quantity of coal is burning. Once the mine or the involved section has been temporarily sealed, gases, ratios, and gas-derived equations can assist personnel in determining how conditions within the sealed volume are changing over time. To alleviate potential explosions when fresh air is once again introduced into the sealed volume, equations and a diagram have been developed to predict the likelihood of an explosive atmosphere. Similarly, prior to commencing recovery of a mine or section, equations exist that can assist in determining if the fire will rekindle when air is reintroduced. This paper serves as an overview to remind and/or instruct readers about gas-sampling methodologies and gas analyses to assist in determining the status of underground atmospheres.

Jan 1, 2006

By R. L. Kloberdanz

Peruvian legislation requires the preparation of an Environmental Impact Study (EIS) for new and expanding mines/beneficiation facilities and the preparation and implementation of an Environmental Adjustment and Management Program (PAMA) to control and mitigate environmental impacts associated with existing mining/beneficiation activities. Shepherd Miller, Inc., developed guidance documents for preparing an EIS and PAMA for Peru's Ministry of Energy and Mines and presented workshops to Peru's mining industry on preparing an EIS and PAMA. This paper discusses the process and approach taken and the results.

Jan 1, 1998

By Gerald A. Muson, Fremont F. Clarke

"INTRODUCTION The use of scrap mica as an industrial raw material has grown rapidly during the past two decades. Demands by various industries for ground mica for use in the roofing, paint, rubber, plastics, and wallpaper trades as well as for less extensive uses in insulation, oil-well drilling, welding, pipeline enamel, decorative material, and for other purposes exceed present (1947) supplies.A small proportion of the raw material used comes from the Black Hills of South Dakota, where casual recovery has been practiced in the exploitation of pegnatite deposits for more valuable minerals. The annual production of scrap mica in the Black Hills for the years 1939 to 1946 is shown in figure 19. 4/Although small, this production of scrap mica materially augments the incomes of numerous operators.Volume production of mica would offer attractive opportunities for obtaining steady and more economical supplies of the rare minerals as byproducts. Appreciable supplies of beryl, lithia minerals, sheet mica, tantalite-columbite, and cassiterite could accrue. Furthermore, a stable scrap-mica production would complement the production of quality feldspar, for which the Black Hills pegmatites are noted, and would help balance the economy of pegmatite mineral production.Mechanical methods of separation are requisite to production of enough scrap mica to be generally profitable. Various phases of the characteristics end treatment of mica have been investigated by the Bureau of Mines. A bibliography of these reports is appended.In 1945 the Bureau of Mines conducted pilot-plant tests to recover scrap mica by selective screening of crushed pegmatite. More recently the problem has boon studied in the Pegmatite Research Laboratory to aid in developing technological methods by which scrap mica may be separated from crushed pegmatite."

Feb 1, 1949

By James S. Browning

[The objective of this project wan to determine the technical feasibility of recovering the associated copper, lead, and zinc from the pyrrhotite axe, of the Great Gossan lead, which has bon pined only for it:, sulfur and iron contents so far. The report constituted a description and discussion of small-scale Preliminary studies. This great pyrrhotite or body has strategic value, inasmuch it contains considerable quantities of zinc, copper, and lead, as well as the iron rend sulfur. The recovery of the: copper, lead, and zinc, associated with certain of the pyrrhotite ore bodies, could augment our domestic supply of these metals.]

Jan 1, 1953

By Roderick Eggert, Dipesh Dipu

We look at the empirical evidence of coal block auctions in India to understand how competitive intensity affects the bid amounts in common value auctions. The results suggest that competitive intensity measured through the number of bidders for a coal block is instrumental in determining the bidding outcomes. The presence of higher numbers of bidders in the auction leads to higher bids - every additional bidder causes the bid amount to rise by INR 142.67 per tonne of coal for auctions studied for 127 coal blocks from 2014 to 2023. The paper also examines the moderating and mediating effect of competition on bids and on excess of bids from the comparative market price of coal from alternative source of Coal India Limited. The results indicate that competitive intensity does not have statistically significant impact on the relationship between common value of coal blocks and bids, neither as a moderator nor as a mediator. The strategic behavior of the bidders has also been observed as bidders have been seen to bid in a higher than market price in order to outbid the competitors.

Feb 1, 2025

Jan 1, 1998

By J. R. Nettle

The development of a process for upgrading offgrade titanium metal by electrorefining in molten salt led to an investigation of the electrotransfer characteristics of selected metals when alloyed with the titanium to be refined. Previous tests on seven binary titanium alloys showed that the degree of transfer of the alloying constituent depends on the constituent and on the operating procedurese.5 This report describes tests on electrorefining ternary mixtures of titanium with selected metallic elements. Ten alloys were prepared from high purity titanium and 2-1/2 percent of each of the metal pairs selected from the same elements used in the binary study; manganese, vanadium, chromium, zirconium, tin, molybdenum, aluminum. Operating variables were similar to those investigated in the binary alloy study that gave minimum alloy metal transfer. The data presented indicate the transfer characteristics of the various metals and combinations tested relative to each other.

Jan 1, 1962

By Xiaodong Wang

A liquid metal flow generated by a magnetic field whose traveling direction is periodically reversed, the Reversed Traveling Magnetic Field (R-TMF) is studied. The modulation frequency ranges from 0 to 6 Hz. Ultrasonic Doppler velocimetry probes the generated fluid flow. Depending on the modulation frequency, a number of characteristic flow features are exhibited. A transition frequency (approximately 4 Hz) exists, above which the flow is no longer sensitive to the force modulation. Below this transition point, the amplitude of the velocity oscillation increases, and then below fm = 0.05 Hz, it saturates around a value close to that observed without any modulation. A theoretical model to obtain an analytical solution of electromagnetic force and to predict flow motion is developed, which is fairly in agreement with the experiments.

Jan 1, 2009

By Maurice Deul

This bulletin summarizes the work conducted under the Bureau of Mines methane control research program during the years 1964 to 1979. This research effort was directed toward improving existing methods and developing alternative methods of reducing the explosion hazard during mining. The research was performed in three general areas: (1) basic factors that control the emission of methane into coal mines, (2) methane control during mining, and (3) methane drainage in advance of mining. Topics discussed in this bulletin include the magnitude of the methane problem; the equipment and instruments developed; the geological, chemical and physical parameters that control the movement of methane in coalbeds; the direct method of determining gas content; the estimates of gas content from adsorption data; and methane drainage, through shafts, through horizontal boreholes, through vertical boreholes, or through slant holes. Improvements in ventilation, control of methane in gob areas, and water infusion are also discussed, as is the potential use of coalbed methane as a supplement to natural gas supplies. This bulletin provides a comprehensive source of information on the accomplishments of the Bureau's methane control research program, on the technology developed, and on the direction of further research.

Jan 1, 1986

By Tanner A. C, Harraway D. H

Various circuits were tried at Mount Isa Mines during the period 1959 to 19G3 with the objective of improving the differential flotation of galena and sphalerite. Many benefits and disadvantages of the various circuits were revealed. An analysis' of ore characteristics and their effect on flotation was made -and resullted in the design of a proposed circuit which is currently in the process of installation.INTRODUCTIONSince 1936 when lead-zinc sulphide flotation commenced at Mount Isa, at least three types of ore have been encountered.Each ore has presented problems to flotation metallurgists.The three types of ore are,1. partially oxidized upper level sulphide ore,2. Black Star ore from the lower levels with its carbonaceous fraction, and3. Black Rock ore which is similar to 2, but more free milling.In retrospect a number of the metallurgical successes of the past were short lived. Often flowsheets or 0perating practices were designed to solve a single metallurgical problem associated with the current ore being treated. As the ore changed the problem would vanish and the method originally taken to counter the problem could become unnecessary or deleterious to the treatment of the new ore. The general lesson learnt from-the past-is-that thetreatment of Mount Isa lead-zinc ore involves a number of equally major problems...

Jan 1, 1963

By Joan Weinberg

The real gross national product (GNP) expanded by 2.3% during the second quarter, down from the anomalous 4.4% growth rate in the previous 3 months. If the expansion continues through October, it will have lasted 5 yr and become the second longest in 40 yr.2 As in the first quarter, improvement in U.S. exports played a role in the continuing--albeit slow--growth. More than 2 yr of declines in the dollar relative to currencies of other industrial countries have contributed to a slight reduction in the trade deficit in real (volume) terms, as real net exports of goods and services rose $1.9 billion (table 1). Exports grew a strong 12.1% while imports, which had fallen the previous two quarters, rose 7.4%. Manufactured goods and petroleum products accounted for most of the second quarter import increase. The American Petroleum Institute estimates that the volume of crude oil and refined products imports in the first half of 1987 surpassed those in the same period last year by 7.5%, reflecting falling domestic production and higher than expected demand. Expenditure on durable goods--those that last at least 3 yr-by both consumers and producers also contributed to the second quarter expansion. Personal consumption of durable goods rose 9.0%, after having fallen the two previous quarters. Motor vehicle purchases accounted for most of the second quarter increase and the first quarter decrease. Sales of automobiles surged in the last quarter of 1986, as consumers rushed to capture the sales tax deduction that was eliminated on January 1. Sales fell in the first quarter of 1987, but have now moved closer to the trend line exhibited in the first three quarters of 1986. Automobiles accounted for half the 0.8% July gain in retail sales, and two-thirds of the 1.4% June gain. Producers durable equipment purchases also rose this quarter, accounting for the increase in nonresidential fixed investment.

Jan 1, 1987

The modern theory of sampling of particulate minerals essentially consists of a recent generalization of the procedures for applying and calibrating the formula usually known as ?Gy?s Formula? for sampling variance control, in which the central concept is a parameter called the liberation factor l. A model which can be experimentally adjusted was proposed by one of the authors several years ago, based on geostatistical considerations. This new model, which relates the liberation factor to the sizes of the fragments and mineral grains, solves the usual difficulties faced in the past, and permits predictions that are well verified in practice. Unfortunately, an older, arbitrary and less general formula is still widely used. The vast majority of today?s misapplications of Sampling Theory of Particulate Materials can be traced back to the use of this antiquated and generally incorrect model. Following a brief history of the models used for the liberation factor and a description of its main variable, the liberation size, and to illustrate the importance of proper modelling of l, this paper presents demonstrative calculations of the absurdity of the incorrect model using the particular case of gold mineralization as an example, followed by some more positive examples of application.

Jan 1, 2002

By D. O. Hamiltion

The ISMS program provided for the development and demonstration of equipment modifications in both conventional and continuous coal mining systems. This report describes activities during the demonstration of the conventional equipment and includes machine performance, results of data gathering, system evaluation, and recommendations for implementing improvements.

Jan 1, 1976

By David R. Peterson

This user's manual covers a set of 5 computer codes which were generated during development of a simulation of deep ocean mining operational economics. Table 1.1 provides a summary of these codes, and a more thorough description of each follows, In addition to the descriptions in this user's manual, internal documentation is provided throughout each code, except for the very simple ones, for ease of understanding or possible modification. The two major codes are MINER, which performs the deep ocean mining system operational simulation, and MSWEEP, which calculates the sweep and feed efficiencies for a set of collector paths generated by MINER. The standard operating procedure is to input the system and operating parameters to MINER, which computes a set of collector paths automatically and stores the information in the fife PATH.DAT. MSWEEP subsequently retrieves the collector path data in PATH.DAT, and uses it to calculate sweep and feed efficiency. Separating MINER and MSWEEP allows parmetric execution of MSWEEP without recomputing the collector paths with MINER. PIPEST, RESP, and OBSTCL are special-purpose codes described in more detail in the following documentation.

Jan 1, 1979

By Robert H. Peters

Groundfall accidents have been the leading cause of fatalities in the underground coal mining industry for many years. Statistics from the Mine Safety and Health Administration (MSHA) indicate that approximately half of the victims of these fatal accidents were in an area where no devices had been installed to support the mine's roof. This report was prepared by the U.S. Bureau of Mines to summarize the opinions of 268 coal miners, 29 rust-line supervisors, and 30 MSHA inspectors concerning why people go under unsupported roof, and how to prevent this behavior. Interviews were conducted at six minesites.

Jan 1, 1991

The mineralogy of nickel slags from the flash smelter of Western Mining Corporation Ltd. at Kalgoorlie was studied. Residual magnesium silicates in the sulphide concentrates raise the melting point of the slag and result in the formation of magnesium-rich olivines. Addition of lime lowered the melting point, and, in slowly cooled slags, resulted in the formation of a pyroxene.Magnetite and sulphides were also present in all slags.The converter slags contained an olivine near fayalite in composition, together with wiistite, magnetite, and a little sulphide.Accretions from the hearth of the flash furnace were largely composed of magnetite with subsidiary olivine similar in composition to those of the flash furnace slags.Wall deposits, however, were largely composed of nickel ferrite and nickel-iron olivines.

Jan 1, 1976

By P. M. Daling

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume II of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 2006

By R. L. Marek

The number of persons fatally injured in the California petroleum industry in 1932 was 24, a decrease of 6, or 20 percent from the number killed in 1931. The decrease in the number of fatalities occurring in 1932 caused the fatality curve of the California petroleum industry to reach its lowest point in 10 years. Changing conditions in the oil industry - reduced personnel, decreased active field development, and curtailed production - have undoubtedly caused a part of this decrease, but continued accident-prevention efforts by the industry have also contributed to the reduction in the number of fatalities for 1932. The Bureau of Mines has analyzed and reported annually the fatalities in the California petroleum industry for a period of 10 years. Figure 1 shows the trend of fatal accidents during that period. Fatality statistics for 1932 show that the drilling and producing, pipe line and transportation, and refining and natural gasoline divisions of the industry had fewer accidents in 1932 than in 1931, sales and marketing being the only division that showed an increase over 1931. The number of fatalities by divisions for 1931 and 1932, percent of total, and percentages of increase and decrease are given in Table 1.

Jan 1, 1933

By R. V. Ramani

One area of study in the Coal Mine Injury Analysis project was to illustrate and enhance the ability of mine safety management personnel to apply analytical techniques to injury experience data and to justify requests for funds for safety enhancement actions on a cost/benefit and other quantitative basis. Four volumes of this final project report detail (1) the objectives and scope of the mine safety management research, (2) the results of literature review, and case studies, and (3) models developed for mine safety management. The four volumes are titled as Volume III: Mine Safety Management, Volume IV: Analytical Techniques for Mine Safety Management; Volume V: Mine Safety Management Case Studies and Volume IX: Training Cost Model. This volume deals with the development of a microcomputer based training cost model (TCM) which can be used to analyze training cost implications of various types of training. The model has been developed using Aston Tate's dBASE III plus language. The computer program and a test run of the model are presented in this report.

Jan 1, 1993