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By R. E. Ray

In an effort to reduce the risks to underground miners of health hazards associated with exposure to high concentrations of diesel particulate matter(dpm), the Mine Safety and Health Administration(MSHA) published proposed rules in 1998 limiting dpm exposure in both underground coal and metal and nonmetal mines. The proposed rule for underground coal mines would require removal of 95% of dpm by mass, while the rule for metal and nonmetal mines would eventually limit total carbon exposure from dpm to 160 micrograms per cubic meter of air over an eight-hour shift. The comment period for both proposed standards ended on July 26, 1999.In this session, representatives from MSHA, the National Institute for Occupational Safety and Health (NIOSH), equipment manufacturers, labor and industry will discuss the impact of the proposed regulations on mine operations and worker health. Questions will be taken from the audience after brief presentations from each panelist. This paper provides a compilation of written summaries of each panelist’s opening presentation.

Jan 1, 2000

By H. Haselhuhn

Filtration of hematite ore slurries can be a bottleneck in some hematite processing plants due to inadequate filtration rates caused by the dispersion of fine particles. Flocculation of fine particles in the slurry decreases the specific cake resistance of the filter cake allowing for increased filtration rates. CO2 sparging of hematite slurry was shown to increase the filtration rate by altering the pH and the surface chemistry of the particles. It was shown that an increase in filtration rate of 278% can be accomplished by lowering the pH from 11 to 6.5 using CO2. This was attributed to increased flocculation of hematite and silica particles in the ore.

Jan 1, 2012

By Ovsei Volberg

Motion capture involves recording the position and global orientation of joint sensors of a real object, in most cases a real person performing some human activities. This information is usually recorded at uniformly spaced instances of time, or as it is often called frame-by-frame. Then the recorded motion data sets are processed and mapped into a skeleton hierarchy of a virtual, computer simulated human figure to control the motion of the virtual human in the computer simulation. In the first part of the paper we review several new techniques developed to facilitate the manipulation, noise reduction, storage and reuse of captured data, which have a potential to reduce the overall cost of motion simulation and improve its realism. In the second part of the paper we consider the real life problem of reducing a worker?s risk from being hit by underground mining machinery in a confined space. We formulate a set of requirements to motion editing for this particular task and analyze the limitation of existing techniques

Jan 1, 2000

By Peter Loehr

Full-face tunnelling machines were introduced into German coal mines 12 years ago. It was aimed to utilize these highly efficient systems to drive mine tunnels in rock so that the large demand for development work in some mines could be met. A characteristic feature of coal deposits in Germany - and particularly in the Ruhr Area - is a thick overburden strata. Access is therefore only possible through vertical shafts. A network of horizontal drivages leading from these shafts open the deposits between the different mine levels. The hardcoal-bearing formations are multi-folded and heavily tectonically stressed. Apart from a few extensive fault zones there are many single faults of different natures in the carboniferous strata. During the course of decades coal mining has penetrated to ever increasing depths. Nowadays coal is mined from depths of between 600 m and 1,200 m. The effects of ground pressure in connection with extremely varying rock strengths and high temperatures are particular difficulties which have to be overcome during drivage work. The first full-face tunnelling machines to be applied in the mines had originally bee deigned and developed for tunnelling projects. Not only the machines themselves, but also the back-up equipment had to be adapted to meet the special demands of German coal mines.

Jan 1, 1983

By Wallace W. Key

This report concerns types, quantities, specifications, and uses of non-metallic minerals as a basis for improving their supply, conservation, and utilization. Supply-demand details concerning mineral fillers, rooting granules, and roofing rock used in asphalt are incorporated in this report, along with highlights on production and sales of rooting, floor tile, and other related asphalt products of California. Comparable data for the United States are included. Although large quantities of commercially prepared mineral fillers are used in asphalt for paving and related applications in other States, addition of commercial fillers for these uses rarely is required in California because of the natural tines available. On the other hand, California manufacturers of asphalt products other than having utilize about 300,000 tons of asbestos, diatomite, limestone, mica, soapstone, and other nonmetallic minerals as filler, mainly for reeling and flooring. Also about 500,000 tons of roofing, granules is produced in California, most of which goes into roofing manufacture in California. In addition. A significantly large and growing tonnage of relatively coarse mineral aggregates Ire used on low-angle, built-up, asphalt roofs to produce in attractive surface and offer protection against the clements. Clearly ill minerals used in asphalt products manufactured in California come from local sources, except asbestos and mica--and there are indications that local deposits of those commodities could be utilized in some use categories.

Jan 1, 1966

By B. Cousins

Flotation reagents are critical to the optimum performance of flotation circuits. How a flotation reagent performs within the first few cells of a flotation train is a key indicator of how well it will perform throughout the entire circuit. A method to compare reagent performance was recently developed by Ashland Water Technologies. The procedure involves collecting a timed sample of concentrate from each cell and then measuring the volume of the settled solids. An estimate of the percentage of concentrate collected from each cell can then be mathematically determined, providing an understanding of the recovery changes in each cell. Data from trials at a coal flotation circuit are used to demonstrate the method's validity.

Feb 27, 2013

By John D. Watson

The results of extensive field tests of a new and powerful method of hard rock excavation are presented in this report.* The method, known by the acronym REAM (Rapid Excavation and Mining), employs high velocity, smooth bore cannons to efficiently deliver energy to the rock and has been demonstrated for underground tunneling, drilling, surface benching, scaling, and secondary breakage in hard granitic rock at the Hope Valley Mine test site in California. Solid projectiles made from inexpensive materials such as concrete or steel, and weighing from 8 to 12 pounds, are launched by conventional high speed cannons and impact the rock at velocities of 5000 feet per second--an impact energy of about 4 million foot pounds (Figure 1). The energy applied at peak pressures of nearly 2 million psi over a period of tens of microseconds breaks down the rock by a complex mechanism of crushing, spalling, and initiation and propagation of fractures produced by the interaction of successive impacts and free surfaces. The main objective of the tests during 1973 was a demonstration of controllability of the underground operation of a silenced cannon. To accomplish this objective a 90-mm cannon

Jan 1, 1974

By T. Yegulalp, R. Farrauto, A. Belova, M. Castaldi

Calcium oxide, with its ability to capture and store carbon dioxide, is emerging to become an important tool in carbon management. Calcium oxide can be used reversibly to capture carbon dioxide in situ and then be regenerated to produce a pure stream of carbon dioxide ready for sequestration; the Zero Emission Coal Alliance technology utilizes this property of calcium oxide to generate emissions-free electric power from coal. The reaction of calcium oxide with carbon dioxide resulting in thermodynamically stable carbonate is well understood; however, the efficiency of this reaction is limited by the diffusion of gases through bulk calcium oxide and through a layer of carbonate formed on the surface. In addition, the regeneration of calcium oxide is an endothermic reaction and is favored at high temperatures. The purpose of this paper is twofold: first, to address the diffusion limitation, a thin layer of calcium oxide, supported on a high surface area material, is studied thermogravimetrically to demonstrate the physical adsorption of carbon dioxide on calcium oxide. The adsorption is to take place at temperatures lower than required to form calcium carbonate.

Jan 1, 2007

By W. P. Barnett

In 1988, the U.S. Department of Energy's Pittsburgh Energy Technology Center identified three coal cleaning options for achieving flexible environmental control strategies aimed at reducing energy-related SO2 emissions. These are selective agglomeration, advanced froth flotation, and advanced cycloning. Each technology relies on maximum liberation of pyrite and other mineral matter through feed coal comminution to fine and ultrafine sizes. Research projects designed to expeditiously develop each of these technologies to the point of commercial viability were initiated. This paper will present the status of these projects and the application potential of each technology to coal beneficiation.

Jan 1, 1992

Jan 1, 1967

By J. W. Thompson

RAILROAD GRANT-MDIERALS. Diatomaceous or infusorial earth when found in such quantity and quality as to render lands containing deposits valuable therefor are mineral lands within the meaning of the mining laws and must be excepted from grants to the Central Pacific Railway Company. Central Pacific Ry. Co., In re, 45 Land Decisions, 223, p. 226. RAILROAD GRANT-CLASSIFICATION, If any evidence of minerals is found upon lands within a railroad grant and the showing is sufficient in the opinion of prudent and qualified persons to warrant further exploration and expenditure, with reasonable prospects of success, then the land can not be classified as nonmineral and is not subject to the grant to a railroad company. But where there is no present indication of minerals nor any geological evidence upon which to base a mineral finding, land should not be classified as mineral, or held for further classification and reserved from the railroad's grant, upon the surmise that future prospects might disclose evidences of minerals. Southern PacUl.c Ry. Co., In re, 45 Land Decisions, 326, p. 329. INDEMNITY SELECTION BY RAILWAY COMPANY, Under section 3 of the act of July 2, 1864 (13 Stat., 365), and the joint resolution of May 31, 1870 (16 Stat., 378), the Northern Pacific Railway Company could take coal and iron land within its primary or grant limits. It could not base an indemnity selection upon the claim that certain land was coal or iron in ;;haracter, as such land was not lost to it as part of the grant. But the company was authorized to select other lands in lieu of those lost because of their mineral character, but the word "mineral" did not include iron or coal, and, accordingly, the railroad company was entitled to take coal lands under its indemnity selection.

Jan 1, 1917

By A. D. Hahn

This report describes and gives the results of an examination by the Federal Bureau of Mines of ilmenite-bearing placer sand deposits in the 24-mile long valley of Otter Creek, Kiowa and Tillman Counties, Okla. Drilling and sampling was completed in three periods between October 1956 and September 1957. Mineralogic studies and mineral-dressing tests on recovery of ilmenite and other heavy minerals from composited samples of the sands were made in Bureau of Mines laboratories at Rolla, Mo., in 1957 and early 1958. Otter Creek rises in and drains the southwestern extremity of the Wichita Mountains, which are represented locally by knolls and ridges of gabbro and granite surrounded by plains floored with flat-lying Permian red beds. The valley fill consists of a basal sand-clay component, derived from weathering of the igneous rocks, and an overlying silt-clay alluvium. Ilmenite is present in significant quantity and recoverable grain size only in the basal sand-clay.

Jan 1, 1960

By Zoheir Khademian, Morgan Sears

According to the 2010–2019 Mine Safety and Health Administration (MSHA) accident report database, 91% of reported ground control accidents in US longwall mines were caused by roof instability. Gateroads are subjected to significant changes in loading conditions from the development to the longwall abutment loading phases. When combined with thinly bedded shale roof, found in many US longwall coal mines, the design of efficient roof support becomes challenging. In previous work, the bonded block modeling (BBM) of roof by UDEC was validated against field extensometer measurements in a longwall entry roof at a 180-m depth of cover. The BBM was shown capable of capturing delamination and buckling of shale roof, one of the main roof instability mechanisms in longwall mines. This paper presents the recent findings on the roof-support interaction using BBM models of the same longwall entry. The effects of cable bolts, roof bolt density, and strap support on potential roof instability are studied. Results demonstrate the potential for BBM numerical models to help understand the complex roof and support system interactions and to assist with optimizing gateroad support systems.

Feb 13, 2024

By S. Hardcastle

Tele-remote operation of production equipment from surface will change the design criteria for underground mines. And for ventilation, with machine operators on surface, conventional planning to dilute and remove pollutants can become redundant. Natural Resources Canada with industrial partners are investigating what will be the new environmental design criteria. Additional complications include new mining equipment being designed without standard services and mines’ desire to eliminate conventional auxiliary ventilation. Findings to date show the cooling of equipment’s hydraulic systems to be the most demanding element, especially in dead-ends and when stationary. Consequently, revised ventilation based heat control strategies for equipment are being developed for the automated mine of the future.

Jan 1, 2001

By David H. Searle

This paper will discuss the common trends existing in various Canadian jurisdictions for the closure and reclamation of mines. Included will be a discussion of the requirement to post security as well as its form and how security is calculated and refunded. Reclamation can no longer be left to the end of mine life. Progressive reclamation must occur throughout mine life and must be part of the mine plan from the beginning.

May 1, 2006

By Wilbur L. Webb

This publication reports on the design, fabrication and test of an Improved methane monitor system for compliance to 30CFR75.313. The system will Initiate automatic shutdown of mining machinery when excessive concentrations of methane are encountered. The prime consideration: In the design were small size, Improved accuracy and reliability, fast response and a transient resistant power supply capable of reliable operation from any mine power source. The power supply contains an internal battery that provides operating power to the detection system prior to mining machine start-up or after machine shutdown. This report documents the development program from conception through in-mine testing.

Jan 1, 1978

By Kazuya Naito, Nobuyuki Okamoto, Natsumi Kamiya

JOGMEC (Japan Oil, Gas and Metals National Corporation) became the first entity to sign an exploration contract for Cobalt-rich Ferromanganese Crusts (Crusts) with the ISA (the International Seabed Authority). The contract was signed on 27 January 2014, and 15 years exclusive rights for exploration activities had started in the contracted area, located in the North-Western Pacific Ocean. JOGMEC had already conducted basic scientific surveys around the contracted area from 1987 to 2012. Activities by JOGMEC that will be undertaken during the first 5 years of the contract include examination of geological and acoustic surveys, environmental baselines surveys, and undertaking basic studies of R&D in mining, processing, and smelting technologies. Geological surveys will include analysis of rock core samples, using BMS (Benthic Multi-coring System). Deep-towed TV Camera will be used to estimate the distribution of crusts deposit and to get basic environmental data of deep-sea megabenthos. Water sampling, marine sediment sampling, and installation of mooring systems on the seafloor will also be conducted as a part of environmental surveys.

Sep 1, 2014

By Jos. R. Guiteras

This paper is one of a series published by the Bureau of Mines on mining and milling methods and costs. It describes operations in the Alma district of Colorado in September 1937, supplemented by some additional data collected in July 1938. ACKNOWLEDGMENTS The author wishes to express his appreciation of the friendly cooperation extended him by the mine operators in the district. The greater part of the information was obtained from mine and mill superintendents to whom individual acknowledgment is made in the text.

Jan 1, 1940

By Thomas P. Mucho

Cable bolts are emerging as the newest ?twist? for roof support in U.S. underground coal mines. For decades cable bolts installed in underground metal mines in the United States and Canada used cement-based grouts for anchoring. The cement anchoring process, because of the time and expense for installation, made cable bolts impractical for use in coal mines. Today, the introduction of resin-anchored cable bolts provides a system more consistent with tradi­tional U.S. coal mine roof bolting practices and requirements. Expecta­tions are that the utilization of cable bolts for a number of U.S. mining applications will expand, particularly in coal mining.

Jan 1, 1998