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By J. J. Webb

At Kerr-McGee's Galatia Mine in southern Illinois, the need for safe and efficient longwall moves prompted a detailed planning effort. Galatia Mine operates two longwalls on separate coal seams with different geologic conditions. An overview of the longwall move planning as related to manpower training, roof control, ventilation, transportation, equipment recovery and setup will be discussed. The impressive safety record achieved during each of the longwall moves at Galatia Mine verifies that health and safety planning does play a major role.

Jan 1, 1994

By Chee S. Theng

As the 2016 president of the Society for Mining, Metallurgy & Exploration Inc., I am pleased to present the 2016 issue of the Transactions of the Society for Mining, Metallurgy & Exploration Inc., Vol. 340. A significant portion of the contribution that we make as a professional society is the publication of professional and technical papers that accelerate the advancement of scientific knowledge and enable the transfer of technology. Communication within the mining community is the key to a successful society. This technology exchange continues a tradition that dates back to the 1871 meeting of 22 mining engineers in Wilkes-Barre, PA, that resulted in the founding of the American Institute of Mining, Metallurgical and Petroleum Engineers (AIME). Those individuals envisioned that these transaction volumes “would form a most valuable and greatly needed addition to our professional literature.” This volume fulfills that pledge. The 2016 Transactions contains some of the most interesting research and insights from the past year and features an international slate of authors spanning industry, academia and government. Papers include the latest findings from the U.S. National Institute for Occupational Safety and Health (NIOSH) and special-issue articles on process development testing. The 2016 Transactions consists of a total of 65 technical papers, encompassing all 21 papers published in 2016 in the Technical Papers Section of Mining Engineering (Vol. 68) and all 27 papers published in 2016 in Minerals & Metallurgical Processing (Vol. 33). Additionally, this volume contains 17 papers that are being published for the first time in this issue. The papers presented in this volume were written by some of the most distinguished professionals in the industry worldwide. All of the technical papers were peer-reviewed. The process of review and publication requires much hard work by authors, reviewers and our publications staff. As the 2016 president of SME and on behalf of all our members, I would like to extend our gratitude to all whose volunteer efforts contributed to the publication of this volume.

Jan 1, 2016

By Emily Wortman-Wunder

As the 2012 president of the Society for Mining, Metallurgy, and Exploration, Inc., I am pleased to present the 2012 issue of the Transactions of the Society for Mining, Metallurgy, and Exploration, Vol. 332. A significant portion of the contribution that we make as a professional society is the publication of professional and technical papers that accelerate the advancement of scientific knowledge and enable the transfer of technology. Communication within the mining community is the key to a successful society. This technology exchange continues a tradition that dates back to the 1871 meeting of 22 mining engineers in Wilkes-Barre, PA, that resulted in the founding of AIME; those individuals envisioned that these transaction volumes “would form a most valuable and greatly needed addition to our professional literature.” This volume fulfills that pledge. The 2012 Transactions is the third Transactions to take advantage of new publication technologies. It is available solely as an online subscription. The new format better suits the way this material is used and, ultimately, better enables the transfer and dissemination of knowledge. The 2012 Transactions contains some of the most interesting research from the past year, including a paper on the uranium boom in Namibia, work on improving the safety of coal pillar extraction, ways to improve the optimization and efficiency of various mine activities and the newest research from the U.S. National Institute for Occupational Safety and Health (NIOSH). The 2012 Transactions consists of a total of 67 technical papers (550 pages, including index), including all 18 papers published in 2012 in the Technical Papers Section of Mining Engineering magazine (Vol. 64) and all 31 papers published in 2012 in Minerals & Metallurgical Processing (Vol. 29). Additionally, this volume contains 18 papers that are being published for the first time in this issue. The papers presented in this volume were written by some of the most distinguished professionals in the industry worldwide. All 67 technical papers were peer-reviewed. The process of review and publication requires much hard work by authors, reviewers and our publications staff. As the 2012 president of SME and on behalf of all our members, I would like to extend our gratitude to all whose volunteer efforts contributed to the publication of this volume.

Jan 1, 2012

By John F. Papp

Chromite is used both as a metallic and nonmetallic mineral. Chromite ore is used as the source of chromium by the metals industry and is used, without chemical alteration, in the refractory and foundry industries. Chromite ore is also the source of chromium for the chemical industry. On average worldwide far more chromite ore is used by the metallurgical industry than by any other industry. Thus, although the primary purpose of this chapter is to describe the nonmetallic uses of chromite, the metallurgical uses must also be discussed in order to provide a complete description of this commodity.

Jan 1, 1994

By H. S. Puttanna

Bound water plays an important role in the processing and utilization of numerous materials and mineral processing systems. The fundamental nature of this near surface bound (vicinal) water is yet to be understood in its complete detail. The objective of this paper is to use dielectric measurements to characterize the bound water near hydrophobic and hydrophilic oxide surfaces. It is anticipated that a combination of dielectric property measurements and characteristic relaxation times will allow for more effective analysis of the interfacial water.

Jan 1, 1992

By S. E. Phillipson

Slickensides cause potentially hazardous ground conditions in underground coal mines. Investigations by MSHA’s Roof Control Division indicate that many slickensides represent bedding plane faults and drag folds that formed during coal bed decollement, a style of faulting that occurs in shale units above coal seams. These slickensides formed in response to regional tectonic compressional stresses, rather than by differential compaction, and are parallel to folds and thrust faults. This paper relates slickensides in the Appalachian, Illinois, and Black Warrior basins to the structural grain of the Appalachian Mountains, provides descriptions of slickensides, and advocates geologic mapping as a predictive method for identifying areas with adverse ground conditions.

Jan 1, 2003

By E. F. Young

An integrated steel company is an industrial complex ranging from raw materials mining, through pyrometallurgical smelting and refining, and hot shaping, to product finishing and coating. Within this complex is a great variety of operations which use vast quantities of water, and a variety of water uses which can result in pollution of many different types. The industry has recognized most of its problems for some time, and has spent a great deal of money and effort in reducing and eliminating pollution. A recent survey by AISI showed that the industry has spent, within the last 15 years, two hundred forty millions of dollars on water pollution control, and has authorized spending eighty-seven millions more on this type of non¬productive facilities. While much still remains to be done, I think the record to date is one we can be proud of. In this presentation, we will attempt to outline a number of the water pollution problems encountered in an integrated steel company and to show what types of corrective action have been and are being taken, using Jones & Laughlin Steel Corporation as an example.

Jan 1, 1968

By B. T. Field

Pyroprocessing systems range from low temperature dryers to high temperature reactors. The materials and process requirements cover a broad spectrum. It is not the intent of this paper to do a detailed examination of individual processes and equipment, since that can be found in a multitude of other sources; rather it is the intent of this paper to examine the key process variables and offer empirical guidelines to assist in a user?s overall evaluation.

Jan 1, 1998

By Y. Guan

The dissolution behavior of silver and copper from silver/copper alloys in ammoniacal solutions has been investigated using a rotating disc. Oxygen was used as an oxidant. The effect of composition of alloys, concentration of lixiviants, stirring speed and temperature on the overall dissolution kinetics has been studied. Silver / copper alloys of three compositions were used in this study. The atomic percents of silver in these alloys were 76.9, 46.9 and 24.1. The results on the rate of dissolution obtained for these alloys have been compared with that of pure silver and copper under the same testing conditions. A particular emphasis has been given to the galvanic effect on the overall dissolution rates.

Jan 1, 1993

By A. Anani, K. Awuah-Offei

"Accounting for changing duty cycles in equipment matching maximizes equipment utilization and productivity. The objective of this study is to investigate if the optimal number of shuttle cars for a particular panel width is optimal in different segments of the panel. In this study, discrete event simulation (DES) is used to determine the optimal number of cars that maximizes productivity in each segment. Data from a real-life mine is used to validate the model. The study shows that the optimal number of cars for the entire panel may not be optimal for some of the defined segments. INTRODUCTION Fleet optimization is important for efficient mine management. Deploying the optimal fleet minimizes the capital and operating expenditure for particular operating conditions and production targets. In an operating mine, with an already existing fleet, deploying the optimal fleet maximizes productivity or minimizes production cost with the available resources. Hence, a lot of research has focused on how to determine the optimal fleet size for a mining operation, given particular operating conditions. Mine managers and engineers have successfully used discrete event simulation (DES) to determine the optimal fleet size in mines (Michalakopoulos, Roumpos, Galetakis, & Panagiotou, 2015; Awuah-Offei, Osei, & Askari-Nasab, 2011; Ben-Awuah, Kalantari, Pourrahimian, & Askari-Nasab, 2010; Govinda Raj, Vardhan, & Rao, 2009; Yuriy & Vayenas, 2008; Kwame Awuah-Offei, Temeng, & Al-Hassan, 2003). In most cases, the published work on this topic involves determining the number of hauling units to be matched to a loading unit. Many of these examples involve truck-shovel optimization. There are, however, some underground mining examples. For instance, we recently concluded work that involves fleet optimization in underground room and pillar (R&P) coal mining (Awuah-Offei & Anani, 2015). Generally, when DES is used in fleet optimization it involves three steps: (1) Build a valid model of the mining system capable of predicting the required outputs with varying fleet composition; (2) Design and conduct experiments that vary the fleet composition across all feasible options; and (3) Determine the optimal fleet based on the results of the simulation experiments. A major decision in the first step is which outputs should be modeled. Some examples in the literature include productivity, unit cost, loader utilization, queue length, and hauler waiting times (Awuah-Offei et al., 2011; Govinda Raj et al., 2009; Kwame Awuah-Offei et al., 2003). Often, more than one of these outputs are simulated and considered as the objective function of the optimization."

Jan 1, 2016

By Armando Alatorre

The Republic of México is the world's largest producer of celestite/strontium carbonate and natural sodium sulfate. It is also a significant producer of flourspar, barite, graphite, sulfur, feldspar, salt and gypsum. New production may be brought on stream for borates, wollastonite, garnet, calcium carbonate and others. The country covers a geographic area of approximately 2 million square kilometers (760,000 square miles), and is divided into seven geological/geomorphological provinces. Less than 20 percent has been explored in detail for either nonmetallic or metallic minerals. This leaves large areas available for the discovery of world-class industrial mineral deposits. In addition to new deposits of those minerals currently being produced, there is exploration and development potential for borates, magnesite, rare earths, nepheline syenite, heavy mineral sands and numerous others.

Jan 1, 1995

By Gareth Mainwaring

The Cross Harbor Freight Movement Project is currently in the Environmental Impact Statement phase. The scheme is addressing alternative solutions to transport freight across the Upper Bay of New York Harbor, from New Jersey through to Brooklyn, Queens and Long Island. Amongst the alternatives being assessed are two tunnel options; from the north shore of Staten Island through to Brooklyn, and from Jersey City to Brooklyn. These tunnels are approximately 30,000 feet in length, and with up to17,000 feet under the Harbor, would make it one of the longest undersea crossings in the world.. The paper addresses the development of the project, from the Major Investment Study through to the current EIS, and describes the tunnel schemes that are being taken forward. The geological conditions that will be encountered, proposed construction methods, and the ventilation issues associated with such major undersea tunnels will all be described.

Jan 1, 2003

By Fathi Habashi

SOLVENT EXTRACI ION involves two operations: 1) Extraction The metal values in the aqueous phase are extracted by agitation with an organic solvent immiscible in that phase. The two phases are then allowed to separate; the aqueous phase is discarded or recycled and the loaded organic phase saved.

Jan 1, 1970

By R. Asmatulu

According to Darcy's law, the rate of filtration should increase with increasing pressure drop across a filter cake. In centrifugal filtration, the driving pressure is created by the centrifugal forces applied in the free water on the surface of a filter cake. However, the pressure drop can become negative when the free water surface disappears, which makes it difficult to achieve low cake moistures. In hyperbaric centrifugal filtration, this problem is overcome using air pressure to restore the pressure differential. In the present work, various mineral and coal fines have been subjected to hyperbaric centrifugal filtration tests. The laboratory tests show that the moistures of various mineral fines, such as copper and zinc concentrates, phosphate, talc, kaolin clay, and precipitated calcium carbonate, can be reduced substantially below that achieved by conventional centrifuges. Similar promising results have also been obtained with various coal fines in laboratory and pilot-scale test programs and in full-scale plant demonstrations.

Jan 1, 2012

By Richard B. Muter

1. Coal Preparation Terms (General) 1.1 Coal preparation-collectively, physical and mechanical processes applied to coal to make it suitable for a particular use. 1.2 Run of mine (ROM coal)-coal produced by mining operations, before screening, crushing, or preparation. 1.3 Raw coal-coal that has received no preparation other than possibly screening or crushing. 1.4 Raw coal feed-raw coal supplied to a plant or machine, in which it undergoes some form of preparation. 1.5 Coal cleaning-the treatment of coal to lower the mineral matter content (ash). 1.6 Cleaned coal; clean coal-coal produced by a cleaning process (wet or dry). 1.7 Middlings-a product of coal preparation that, by reason of its ash content, is intermediate between coal and discard. It follows therefore that the relative density of middlings is intermediate between those of coal and discard. Middlings may be reprocessed. 1.8 True middlings; bone comparatively high ash particles so nearly homogeneous that their quality cannot readily be improved by crushing and recleaning. 1.9 False middlings; interbanded middlings-middliigs in which the particles consist of bands of coal and shale, and from which the coal may be liberated by crushing 1.10 Refuse-waste material in the raw coal which the cleaning process removes. (See also discard; dirt; stone, No. 1.12). 1.1 1 Reject-the material extracted from the feed during cleaning, for retreatment or discard. 1.12 Discard; dirt; stone--the material extracted from the raw coal and finally discarded. 1.13 Recirculation-the operation in which the whole or part of a product from a process is returned to the feed to the process, e.g., the return of the crushed overflow from a screen to the screen feed for rescreening. 1.14 Foreign coal-coal received at a preparation plant from a colliery other than that to which the plant is attached. 1.15 Imported coal-coal coming from a foreign country, or other state within the country. 1.16 Low-grade coal combustible material that has only limited uses owing to undesirable characteristics (eg., ash content or size). 1.17 Segregation-partial separation of a previously mixed material into its constituents, occurring as a result of differences in either particle size or relative density. 2. Cleaning Characteristics 2.1 Washability-amenability of coal to improvement in quality by cleaning. 2.2 Float-and-sink analysis-the division of a sample into relative density fractions with defined limits, the proportions of the fractions being expressed as percentages of the total sample, commonly with an indication of the ash percentage (and other characteristics, if required) of each fraction.

Jan 1, 1991

By P. Otto, G. Borm, Th. Dickmann, F. Amberg, R. Giese

Based on many years experience, the well approved Tunnel Seismic Prediction System (TSP) has been substantially enhanced for online geological prognosis in underground construction. The method provides high resolution seismic images of the rock mass ahead of a tunnel face via an array of standard anchor rods. These contain3D-geophones and can routinely be installed during the excavation process. A further outstanding feature of the system is the newly developed high frequency repetitive seismic source which can easily be fixed at a tunnel boring machine. A user-friendly software package enables online data acquisition, processing, 3D-visualization, and interpretation.

Jan 1, 2001

By Leonard G. Austin

INTRODUCTION Run-of-mine (ROM) coal generally falls into two major groups: that from underground mining (continuous mining machines) and that from strip mining. Continuous miners produce a finer product and strip mining a coarser product that is crushed to produce the desired size. Further size reduction depends on the proposed use or uses for the coal. For example, for pulverized coal power plants as a rough general rule, the coal is ground or pulverized to 80% less than 200 mesh (0.075 mm) before it is blown into the boiler furnace as a coal-air suspension. For solvent-refined coal processes, the desired size is about <30 mesh (< 0.60 mm); in fluidized bed uses, the coal is typically < 8, in. (< 1.6 mm); for Lurgi pressure gasifiers, the desired size is 1 to 2% in. (25 to 63 mm). Coal preparation plants typically work with a coarse size fraction of 6X 1/14 in. (150X32 mm). The past decades has shown a steady increase in the tonnage of coal cleaned, 1 but it seems probable that the next decades will produce much wider applica- tion of deep coal cleaning before use and that the stages of crushing and pulverization from ROM coal to end use will be integrated with coal cleaning processes. Since different cleaning processes work better with different ranges of coal size and the degree of cleaning possible is intimately connected with the size of coal, a systems design engineer will need as much information as possible concerning the size distributions produced by different types of machines and how these can be modified by different ways of operating the machines. In general, the following questions will be of concern: 1.What type of crusher or grinder is best, or most satisfactory, for reducing a given feed size and type of coal to a desired product size? Frequently, the desired product is smaller than some nominal size, but with as few fines as possible, or the fraction in some size range has to be as high as possible. 2. How big does the machine have to be for a given throughput rate? 3. How much electrical energy (or its equivalent) is required per ton of product? 4. How does the size distribution vary with change in throughput rate, and is a control scheme necessary or desirable? 5. Can the size distribution be readily varied if desired? 6. What is the optimum way to operate a machine in a given system? This section will emphasize certain general principles which guide us in answering these questions. PARTICLE SIZING Since particle size and size distribution are the raw information with which we work, it is worthwhile to review the terminology used. In this regard, see

Jan 1, 1991

By R. R. Rollins

Conventional methods of controlling abandoned mine fires include: loading out, inundation, fire barriers, flushing, and surface sealing. This paper describes a proposed fire-control technique utilizing a new explosive fragmentation method. An impervious barrier is created by using explosive energy and strategic emplacement in boreholes drilled from the surface. Blast round design, average fragment size, and impermeability of the fragmentation barrier are discussed. This barrier, created by the blasted floor rock, could also be used to fill in the open space in abandoned mines for subsidence prevention or control.

Jan 1, 1989

By Charles Kimbell, L. Nahai, E. Shekarchi

INTRODUCTION AND SUMMARY World mineral trade during 1960 to 1984 has shown substantial changes both in value and tonnage. Although fuel commodities dominated total mineral trade during this period, this paper will focus attention primarily on nonfuel minerals. Brazil and Australia, modest producers of iron ore in 1960, have become dominant producers and exporters, together accounting for about half of major iron ore exports in 1984, far surpassing traditional export suppliers such as Sweden. Australia has also become the largest producer and trader of bauxite and alumina, and worldwide alumina trade has increased at the expense of bauxite trade. Similarly, shipments of ferroalloys have increased more than shipments of ores such as those of chromium and manganese. Canada, retaining its first rank in world export of zinc, has become also the leading source of potash and sulfur in world trade, and South Africa has been the dominant factor in chromite, manganese and their respective ferroalloys. Developing countries&apos; share of world copper trade has increased, with Chile maintaining first rank, but developed industrialized countries have continued to dominate production and trade of lead and zinc. Phosphate, sulfur, and potash have been the principal crude nonmetallic minerals traded worldwide. Looking to the near future, dramatic increases in export of iron ore, phosphate, potash and sulfur are not envisaged. Bauxite exports will continue to decline relative to alumina but at a slower rate than in the recent past. Zinc concentrate will continue to be exported but lead will be traded more as metal than as concentrate. For iron and steel, there will be some production shift from traditional producers to certain developing countries and recently industrializing developing countries such as Brazil, India, the Republic of Korea, and Taiwan. In the following sections dealing with specific commodities, it should be understood that information is presented only on the major forms of each commodity that move in trade, and only for a selected group of countries for each commodity or major form of each commodity. Thus, totals shown or mentioned generally represent only the totals of figures presented here and do not include estimates for minor forms of material or for countries that are not listed. However, the data provided is regarded as sufficiently complete to reflect major patterns and trends, and exclusions are there- fore not seen as affecting conclusions that may be drawn from the material provided. FUEL AND NONFUEL TRADE Values of Fuel and Nonfuel Trade The value of world export trade in major mineral commodities (ores, concentrates and scrap, crude minerals, iron and steel, nonferrous metals, nonmetallic minerals and mineral fuels) in 1983, the latest year for which comprehensive data are available, was reported by the United Nations in May 1985 to have totaled over 514 billion current U.S. dollars (Table 1). This was 79% of the historic record high of nearly $649 billion ,current dollars set in 1980, but almost 18 times the current dollar value reported for 1960. [1/] The value of these 1983 exports in constant 1960 dollars was $164 billion (Table 2), only 66% of the record 1980 high of almost $250 billion, and only about 5.7 times the 1960 dollar level.

Jan 1, 1986

By T. R. A. Davey, J. W. Sherman, B. J. DiSanto, G. Bjorling, G. S. Stacey, J. T. Cullom, R. L. Bird, S. E. Woods, J. C. Blair, Jorma Honkasalo

Most pyrometallurgical processes take place at high temperature with rapid chemical reactions when the elements and compounds are usually liquid or gaseous. Smelting. The classical method of obtaining a metal from its ore or concentrate is to smelt it in a furnace. The initial letter "s" of this word implies that, in addition to the physical process of melting, a chemical change also occurs. This is usually the reduction of metal oxide to metal by carbon or through a series of processes involving oxidation and reduction. Since solid-solid contact would not be sufficient to give a high rate of reaction, most smelting reactions occur by medium of two reactions involving solid-gaseous contact: where M represents a metal. The commonly preferred unit for carrying out these reactions is the blast furnace,1 which is a vertical shaft of refractory brick or water-cooled steel in which lumps of metal oxide and coke are fed at the top, and an air-blast is injected through tuyeres (water-cooled pipes) in the bottom. Molten metal is withdrawn from a pool at the bottom of the furnace, while N2, CO, and CO2 gases leave the top of the furnace, carrying some fine dust or fume with them, which

Jan 1, 1985