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By J. H. Stears

This Bureau of Mines report presents information on the use of steel supports in U.S. coal mines, including accident statistics for a 3-yr period and a survey of present applications and problems. It also contains a summary of available steel arch configurations and a description of steel support design criteria for ground control applications.

Jan 1, 1984

By George K. Clement

Manual estimating method through use of equations, factors and curves for preparation of feasibility type estimates for capital and operating cost of mining and primary beneficiation in the United States and Canada of various types of minerals occurrences, except fossil fuels, using state-of-the-art technology. User should have basic estimating experience in the mining industry and/or related fields. Primary usage of this handbook will be for the preparation of preliminary estimate within a reasonable degree of accuracy with relative small amounts of hard input data. Output may be used to determine if a more finite type of estimate should be produced.

Jan 1, 1978

By K. W. Edwards

The formulation of a theoretical basis for the evaluation of in-situ coal through the use of geophysical logs is outlined. This involved the development of an approach to the interpretation of resistivity in environments having multiple conductive and non-conductive components. Utilizing this approach and other conventional interpretation techniques, a program was developed yielding accurate determinations of the in-situ percentages of coal, water and ash for the evaluation of coal deposits. Basic information obtained from the CWA program can be utilized in numerous aspects of total mine planning . Some examples of the practical application of this method are included.

Jan 1, 1978

By Broggi Andrea

Condensates produced by SiO(g) and CO(g) have a crucial importance in silicon production. Condensation will follow the reactions 3 SiOðgÞ+COðgÞ→ 2 SiO2 + SiC and 2 SiO ðgÞ→Si+SiO2. Solid compounds generated during silicon production contain Si, SiO2 and SiC in different microstructures and amounts. In industrial systems, condensates limit the SiO(g) escape to the off-gas system. On the other hand, they can block the gas flowing from the high temperature zone, hence the necessity of studying an optimized condensation process. This review discusses SiO(g) condensation and its interaction with CO(g). The report gives an overview of the condensates found both at laboratory and at industrial scale. The two main compounds are the Si–SiO2 and the SiOx–SiC mixtures. The hypothesis on the mechanism of formation of SiC–SiOx condensates is presented through a wide selection of performed works. The advantages and disadvantages of the former experimental procedures are discussed.

By Swan. J. D.

Repairing and replacing equipment damaged by corrosion and abrasion is a major cost throughout industry, especially in the coal mining industry. Careful study of corrosion and abrasion, and their causes and effects, often leads to the selection of alternative materials which can provide economies. What, actually, are corrosion and abrasion and how do they contribute to the cost of operating a coal-preparation plant? Furthermore, what can be done to alleviate corrosion and abrasion problems and thereby reduce operating costs? These questions will be answered in the following discussion, which will describe the destructive action of corrosion and abrasion and give several methods for controlling corrosion and abrasion losses, These methods include the substitution of stainless steel for carbon steel, the use of corrosion inhibitors, and the use of design to eliminate corrosion and abrasion. Examples will be given illustrating the benefits that have resulted in plant tests when these methods of controlling corrosion and abrasion were used.

Jan 1, 1970

By Robert C. Edmiston

"Further, we search for the veins by observing the hoar-frosts, which whiten all herbage except that growing over the veins, because the veins emit a warm dry exhalation which hinders the freezing of the moisture, for which reasons such plants appear rather wet than whitened by the frost," Georgius Agricola, De Re Metallica, 1556 In view of Agricola's statement, made in 1556, the concept of using the heat released by oxidizing sulfides as an ore guide can hardly be considered a product of twentieth-century technology. In fact, thermal exploration has received relatively little attention in modern times compared to other potential field geophysical methods. There have evolved, however, two basic approaches to thermal exploration for subsurface heat sources. These are 1) the measurement of surface temperatures by infrared, thermal imagery and 2) the measurement of geothermal gradients in exploratory drill holes.

Jan 1, 1974

By Pengfu Tan

A thermo-chemical model of the copper P-S converter and a viscosity model for the converter slag have been developed to predict the behavior of magnetite in the converter slag, amounts of slag and matte, compositions of slag and matte, volume of the bath, bath temperature, slag blow endpoint determination, SEMTECH OPC signals, and the viscosity of converter slags. The predictions of bath temperature, slag and matte compositions, and magnetite content in the slag have been validated by the industrial data. The effects of fluxing strategy, returns and skim charges, oxygen enrichment, and temperature on the magnetite formation in the slag have been predicted and discussed. The effect of oxygen potential, SiO2/Fe in slag, detection of slag blow endpoint, and temperature on Fe3O4 content in converter slag, slag viscosity, liquidus temperature of converter slag and skimming operation has been modeled and discussed as well. Some applications of the industrial operations have been presented.

Jan 1, 2009

By I. James, R. J. Durrheim, M. S. D. Manzi, O. Valeshin, J. Lepine, L. V. Socco, C. Colombero, A. Malehmir, M. K. Rapetsoa, M. Sihoyiya

The FUTURE project aims to enhance seismic surveying in South African mining by integrating advanced acquisition technologies. In this paper, we detail surface and underground seismic surveys at the South Deep gold mine as part of the project. Surface seismic acquisition used co-located broadband micro-electromechanical sensors, one and three component recorders connected to geophones, distributed acoustic sensing using a straight fibre optic cable, along with a 6 ton broadband seismic vibrator operating with 4–180 Hz linear sweeps. In addition, underground surveys employed a combination of straight, and helically wound fibre optic cables, cabled-based and nodal sensors, along with a 500 kg drophammer mounted on a skid steer bobcat. The surface and underground seismic arrays were time synchronised using a GPS-time transmitter to allow for accurate seismic data recording in a GPS-denied environment. Results show the efficacy of these techniques in acquiring high-resolution seismic data, revealing detailed subsurface geological structures and mineralisation down to 3500 m below ground surface. Surface data revealed clear seismic reflections corresponding to the Black Reef and Ventersdorp Contact Reef. An underground P-wave velocity model exhibits low velocity anomalies that are associated with fracturing, while a P-wave reflection stack section shows significant reflections and a degree of faulting below the tunnel floor that was not observed on the surface reflection seismic data. We highlight the potential of these technologies to enhance safety, efficiency, and sustainability in mining. This study sets a benchmark for future reflection seismic surveys, paving the way for safer, more efficient, deep mineral exploration and extraction practices.

Jan 12, 2025

By J. Paraszczak

Metal mining at great depths presents a number of serious challenges for mine operators. Among them is the high demand for fresh air required to cool down mine openings, evacuate noxious gases and contaminants and provide sufficient amounts of oxygen for miners. At the same time, modern mechanized mines extensively use diesel-powered load-haul-dump (LHD) machines, trucks and other mobile equipment. These vehicles not only emit exhaust gases and diesel particulate matter (DPM), but constitute an additional source of heat. As mine regulations get steadily more stringent with regard to air quality, the use of diesel engines has an additional adverse impact on ventilation costs. In this context, the present paper examines possible alternatives for diesel power trains, both those commercially available and those in development. They are reviewed with regard to their principles, required infrastructure, stage of technology development and progress. The questions of their flexibility, practicality and economic viability are also addressed. Finally, their possible benefits and potential for implementation in the conditions of deep metal mines are discussed. The paper concludes with short- to medium-term predictions concerning promising drive alternatives for vehicles destined to operate in deep metal mines.

Jan 1, 2009

By J. R. Hamke

THE WILLISTON basin is the largest known sedimentary basin on the North. American continent. Two-thirds of this large basin lies within the United States in Montana, North Dakota, and South Dakota. Less than 10 years after the first commercial oil discovery in North Dakota in 1951, the petroleum became one of the largest industries in the three-state area. Crude petroleum is now the most valuable mineral resource in the area. In 1960, the basin produced 39 million barrels of worth $100 million at the wellhead. Most of the 137 oil pools covered to date are in Paleozoic carbonates at depths ranging from 3,000 to 13,000 feet. The major producing fields, centered on the Cedar Creek anticline in Montana and the Nesson anticline in North Dakota, produce from depths below 6,000 feet. This report presents descriptions of all phases of the Williston basin petroleum industry, including leasing, exploration, geology, drilling, production, transportation, and refining. Engineering, physical, and production data, maps, and crude petroleum analyses for 137 separate oil pools are included.

Jan 1, 1966

By B. Simser, T. Butler, A. Hall

The longterm future of Glencores’ mining operations in the Sudbury basin area of Ontario, Canada likely depends on mining deposits at depths below two kilometres. To gain a better insight into the rockmass response to mining, a geological scouthole program has been implemented at Glencores’ Nickel Rim Deep and Onaping Depth Project to gain insight into rockmass conditions ahead of the devel-opment face. The scouthole program involves drilling long (up to 600 m) subhorizontal boreholes drilled ahead of the development end and collecting data about the rockmass conditions from various geophysi-cal and mechanical tools (in addition to conventional core logging). Once all data has been collected and the borehole is available, seismic sensors are installed up to 450 m down the hole as part of the micro-seismic monitoring program with the leading sensor always located ahead of the development end. The recorded seismic data is used to provide realtime insight into the rockmass response to mining. On May 20, 2017 a flurry of seismicity with a maximum moment magnitude (Mw) of 0.7 occurred causing damage to the ramp heading. Data from the microseismic monitoring system had indicated that conditions at the development end were changing prior to the rockburst. A back analysis of the scouthole data indicated a clear anomaly in the rockmass at the location of the rockburst. The scouthole data also provided sufficient information to suggest that once this anomalous zone was exited, mining conditions would improve. With the microseismic monitoring system providing realtime information from the rockmass, the area was re-habilitated and ramp development continued successfully. Details of the rehabilitation and adjustments to the ramp development are discussed. Some correlations between the scouthole data and recorded micro-seismicity are also presented.

Apr 26, 2022

Approximately half of all the fuel energy used in the United States is now pro-vided by oil and natural gas. A persistent and rapid growth in energy demand during the last 3 decades has been absorbed largely by the liquid and gaseous rather than solid fuels. In 1948 the energy provided by coal was substantially the same as in 1920. Meanwhile, the use of oil and natural gas each had increased fivefold. On a per capita basis, the change is more significant. Coal consumption has dropped from about 6 tons per person to 4-1/2 tons, while oil has increased from 4-1/3 barrels to 14-1/3, and natural gas from 7,500 cubic feet to about 35,000. These facts would have only academic interest if the United States had unlimited supplies of all fuels. However, while the Nation's reserves of coal are adequate to meet our needs for centuries, those of oil and natural gas appear limited. It is obvious, therefore, that the security of our liquid-fuel position would be greatly enhanced if the supply could be based in an increasing degree on solid fuels, such as coal/and oil shale, which make up more than 95 percent of our fuel reserves, instead of natural oil and gas. In addition, this would create new employment and help to stabilize the market for coal, which may be facing comparatively bleak prospects in the near future unless its position with respect to other fuels is improved.

Jan 1, 1950

By Ronald D. Rothchild

This report describes the results of a study of longwall ignition hazards and specific suppression systems to minimize each of the major hazards. The major ignition hazards were identified by conducting a literature search and conversing with knowledgeable individuals in the United States mining industry. Three classes of potential ignition suppression systems are discussed: triggered suppression systems for face ignition, passive suppression systems, and control of ignition hazard in the gob. The triggered suppression systems included protection for the shearer, head and tail gates, welding equipment, and the shearer power cable. Passive systems include improved ventilation and water sprays, and charges in the shearer head. Gob protection can be improved by isolating the gob from working areas and by introducting inerting agents into the gob.

Jan 1, 1976

By Giorgio De Tomi, Ricardo Tichauer

Mineral exploration is a critical step for success in mining. However, small-scale mining often ignores exploration best practices. This paper introduces the Tichauer-DeTomi Matrix, a tool for assessment of geological uncertainty in small-scale mining. This matrix, which measures the level of compliance of exploration programs in small deposits with industry best practices, has been applied to three small mining projects in Brazil: an artisanal gold mine in the Amazon, a small-scale manganese mining venture in the Northeast, and a small manganese deposit in the Southeast. The application of the matrix resulted in indexes that reflect the actual level of maturity of the mineral exploration program in each project. Therefore, the matrix has shown potential to be an effective tool for assessment of the geological uncertainty remaining in small-scale mineral projects, as well as to identify priority exploration activities for reduction of risks associated with the geological uncertainty. As a risk assessment tool, the TichauerDeTomi Matrix may be helpful in promoting investment and sustained development in and around small mines.

By Constantine C. Popoff

This report reviews and analyzes, by a simple analytical and logical reasoning, the conventional methods of reserve computations of mineral deposits described in various domestic and foreign publications. It brings together, formulates, and evaluates the principles underlying interpretation of exploration data; and ties such principles to the proposed classification of methods. The material is discussed in sufficient detail to allow general application.

Jan 1, 1966

The original manuscript of section 2 of this series of miners' circulars devoted to accident prevention in bituminous-coal mines was completed in September 1944. At that time roof bolting had been tried with some success in the lead-mining district of south-eastern Missouri, but information on the subject was so fragmentary that it was not included as a method of roof support. References to roof support in bituminous-coal mines, therefore, were confined almost entirely to conventional timbering methods. In 1947 the Bureau instituted a research program and intensive study of the general problem of roof control, which emphasized roof-bolt application. The rapid increase in mechanized mining following the close of World War II provided the impetus for the Bureau's roof-control investigations, because the vertical supports used with conventional timber restricted the maneuverability of mechanical face equipment, and the industry wanted to explore every possible method of eliminating interference with the production cycle to gain full advantage of mechanized mining. Moreover, the accidental dislodgment of vertical supports greatly increased the roof-fall hazard. As roof falls have killed and seriously injured more mine workmen every year than any other cause or classification of injury since records have been kept, the Bureau assumed this investigative leadership with the prime objective of substantially reducing the annual toll from falls of roof, including falls of rib and face.

Jan 1, 1958

By Qingwen Shi, Brijes Mishra

The abstract discusses the use of numerical simulations to investigate roof fall in underground mines. It highlights the advantages of the discrete element method (DEM) in simulating large strain problems and fracturing processes, while acknowledging its computational limitations for large-scale problems. The study presents a 3D numerical model coupling the finite difference method (FDM) and DEM to simulate laminated roof failure in a coal mine. The model represents the laminated roof with bonded particles and discontinuities, while the surrounding rock is represented by continuum zones. The research analyzes the fracturing of the laminated roof as the entry advances, demonstrating the coupled method's ability to reproduce laminated roof failure.

Mar 17, 2022

By Paul E. Rosten

Introduction This papers describes some of the latest improvements that have been incorporated or planned by the Cleveland-Cliffs Iron Co. to reduce operating costs and improve pellet quality. The Cleveland-Cliffs Iron Co. operates and manages mining, beneficiation, and pelletizing operations in Michigan, Canada, and western Australia. This paper deals with the grate-kiln pelletizing operations at Republic, Humboldt, Tilden, Empire, and Pioneer in Michigan, and the Adams and Sherman in Ontario, Canada. Table I characterizes each operation in regard to location, ore type, pellet capacity and date that pellets were first produced. All of the operations with the exception of Pioneer and Tilden, utilize downdraft-two-pass grate cycles of drying followed by preheating. Pioneer utilizes an all-downdraft, three-pass grate cycle which consists of three drying zones followed by the preheat zone. The Pioneer and Tilden cycles have been described previously (Lindroos and Koski, 1966; Villar and Dawe, 1975; Koski, 1977). Tilden utilizes a three-pass grate cycle with a stage of updraft drying, followed by two downdraft drying stages. Recuperation systems which supply hot gases to a drying zone from second stage cooling were designed and fur¬nished for Tilden I. Tilden II will be identical. Empire IV will also be furnished with a recuperation system. The Adams grate¬kiln system was retrofitted with a recuperation system. This paper will summarize some of the efforts that are in effect or planned for grate-kiln pelletizing systems to: (1) reduce operating and maintenance costs, (2) reduce energy requirements, (3) improve product quality, and (4) meet environmental standards.

Jan 1, 1981

By Albert W. Scragg

"THE ADMINISTRATION DEPARTMENT consists of six sections, all with their own supervisors, reporting to the superintendent of administration. Although each of these sections is uniquely separate, they all work together, in one department, to provide very necessary services.1. Accounting 2. Purchasing 3. Warehousing 4. Data Processing 5. Inventory Control6. Office ServicesThis department, which now numbers 108 people, had its birth in an office over a hardware store in downtown Timmins in 1964. Initially, only basic accounting and purchasing functions were performed and these, of course, were on a very small scale. The growth of the administration department is a function of the growth of the company."

Jan 1, 1974

By C. W. Davis

During the second year of its existence, the Ore-Testing Section has actively prosecuted work in the standardization of testing methods, in conducting routine tests and analyses for other Government agencies, and in the determination of recommended processes for the treatment of representative ores from mining districts. Close cooperation has been maintained between the members and units of this Section and those of other Sections, J. A. Woolf and J. B. Clemmer have continued to act in an advisory capacity and R. E. Head has contributed valuable assistance in the microscopic examination of ores and metallurgical products that did not respond readily to standard treatment methods.

Jan 1, 1938