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By Hugh D. Olmstead

Typical operations necessary to develop oil and gas reservoirs are reviewed, including exploration, drilling, cementing, completion, work over, sand control, stimulation, enhanced recovery and production. The role of industrial minerals in these operations is described. Some of the opportunities and problems affecting increased use of industrial minerals in drilling and stimulation are discussed.

Jan 1, 1983

By R. M. Hernandez

The Bureau of Land Management (BLM) constructed four passive biochemical reactor systems (BCRs) to treat mining influenced water (MIW) in the Bunker Hill Superfund area near Coeur D?Alene, Idaho between 2002 and 2003. Initially, the BCRs operated very effectively. However, in the past couple of years, the zinc removal effectiveness of the four BLM BCRs has declined [1]. The central objective of this study was to characterize the microbial communities and substrate present within the BLM BCRs and to use these factors to propose strategies to promote sustained sulfate reduction levels. Microbial communities were characterized by quantifying total bacteria and sulfate reducing species. Substrate was characterized by quantifying the percent organic, acid soluble organic, acid insoluble organic, and bioavailable material within the BCR. The results suggest the depletion of bioavailable organic substrates is the primary cause of the decline in zinc removal and not the microbial community structure. The ability to assess the amount of bioavailable organic substrate and microbial community is important to the understanding of the sulfate reducing capacity of the BLM BCRs and developing strategies to facilitate performance enhancement of the current BLM BCRs. The characterization of organic substrate and microbial community structure are also important to improving design of future passive treatment systems for mining influenced waters.

Jan 1, 2010

By R. V. Ramani

In this paper, the application of the concepts of reliability engineering to the evaluation of longwall system performance is illustrated with data from an operating longwall face. A number of cases are analyzed to highlight the impacts of longwall equipment, geological conditions and outby haulage on systems reliability and availability.

Jan 1, 1988

By S. S. Peng

Since the introduction of shield supports in 1975, safety and production in U.S. longwall faces have improved considerably. Many faces had a daily production of up to 8,000-10,000 tons and productivity reached 600 tons per man-shift. But a longwall face requires expensive equipment which slows down the growth rate of the percentage of longwall production. Among the equipment cost the shield support accounts for 50-60%, a very large proportion. Therefore, it will have a large impact on the growth of longwall mining in the U.S. to reduce the support cost (1).

Jan 1, 1988

By Harry Verakis

Electronic detonator systems are an advance in technology beyond conventional electric detonators for initiating explosives and blasting agents. Their use is widening into the mining operations of the U.S.A. Each electronic detonator system differs in design, construction, operation, and testing features and each system is different than “conventional” electric detonators. There are benefits of electronic detonator systems which serve to improve blasting safety. With the introduction of electronic detonator systems for mine blasting, issues were raised about the application of MSHA regulations for shunting and circuit testing. The MSHA regulations for surface and underground mine blasting operations address the use of “electric” detonators. Although electronic detonators are initiated by an electric pulse or current, their design is unlike “electric” detonators. To resolve the issues of shunting and circuit testing with respect to MSHA regulations, a technical and field evaluation of electronic detonators was made and the results are presented.

Jan 1, 2005

By Celeste Powell

Liquid carbon dioxide can be used as a replacement for organic solvents in the extraction of anionic PGM complexes from an aqueous phase. This can be achieved only if highly carbon dioxide-soluble chelating agents are developed because conventional chelating agent-metal complexes, such as trioctylamine-gold chloride, are not soluble in liquid carbon dioxide (although trioctylamine is CO,-soluble). Our novel CO,-soluble chelating agents have a fluorinated tail and a conventional amine head group. Both the chelating agent and the chelating agent-metal complex are soluble at ambient temperature at pressures between 7-35 MPa. Equilibrium constants in the 105 range have been measured (in Freon 113, a low pressure screening liquid for carbon dioxide), indicating that these compounds will strongly bind the metal chloride. For example, 93% of Pt-chloride was extracted into Freon 113 using a 3.5:1I ratio of a double-tailed fluoroalkyl amine chelating:metal chloride. 88% recovery of Pt-chloride into liquid carbon dioxide was achieved using the same chelating agent at a 3.5:1 ratio.

Jan 1, 1999

By D. G. Chedgy

This article presents a novel design, called the Climax High Capacity Processor (HCP), for pre-combustion cleaning of coal. This design is particularly suitable for the plant capacities of 400 -660 TPH. The HCP is different from the conventional designs with an equivalent throughput in three major aspects: 1) the use of one large capacity HM cyclone to separate coarse and intermediate raw coal in a single circuit; 2) the elimination of the conventional secondary magnetics recovery system by use of the high efficiency Climax magnetic separators; 3) the use of "single line" piping with a minimum requirement of ancillary devices. In comparison with conventional designs with similar capacity, the HCP plant costs much less in capital investment, operation and maintenance.

Jan 1, 1997

By S. J. Root

The mineral processing industry supplies raw materials to a wide variety of manufacturing sectors. Large companies such as Ford, Microsoft, and Johnson&Johnson have pledged carbon neutral supply chains in the coming decades, leaving suppliers to reevaluate their energy sources [1–3]. National Renewable Energy Lab [4] has partnered with over 700 organizations with similar goals in mind. The energy needs are broad in scope in the mineral processing industry. Generation IV of nuclear reactors, which is currently under development in both the private and public sector includes a class called microreactors like the small modular reactor XEnergy plans to install at Dow Chemical’s Gulf Coast facility by 2023 [5]. As the name implies, these are smaller than the utility scale nuclear power plants in operation today, and are intended to be more versatile. A specific reactor core design, along with modules could be selected to fit a certain application without needing to design a greenfield power plant. Basic water cooled designs could easily supply shaft work, electricity, and low grade process heat to a facility. More advanced designs, such as molten-salt-reactors and high-temperaturegas-reactors can achieve higher temperatures needed for ore roasting. Similarly, these reactors could produce hydrogen by high temperature electrolysis to use as combustion fuel and reducing atmosphere in blast furnaces.

Feb 1, 2023

By L. P. James, W. W. Atkinson

Utah has produced about 31.7 kt (1 billion oz) of silver, more than any state in the United States except Idaho. Several high-grade ore systems in Utah, where the mines are now closed, occur within large polymetallic limestone-hosted districts related to plutonic complexes. These mines fed several major lead smelters for nearly a century. Interaction of magmatic chloride-rich fluids with carbonate rocks localized significant bonanzas within these districts. A low sulfidation state was produced in the fluids by their passage through limestones. The Bingham openpit mine has also yielded more byproduct silver than other porphyry copper-molybdenum-gold systems. Away from exposed intrusive rocks, some large silver-only systems occur in Mesozoic sandstone and in caldera-related veins in volcaniclastic rocks. Thick permeable latest-Proterozoic basement metaquartzite sequences present beneath western Utah may have been important, as perhaps they were in the Coeur d'Alene district of Idaho, in providing chloride and silver-rich ore fluids. However, it is clear that specific Tertiary magmatic events played an essential role in the evolution of the Utah silver-rich metallogenic province. The largest silver districts in the state are genetically related to Tertiary porphyritic plutonic rocks.

Jan 1, 2003

By Harold L. Lovell

The areas of application, the limitations imposed by water chemistry as well as the advantages and disadvantages in the use of limestone for the treatment of coal mine drainage have recently been described by the authors (1),(2), (3). The process has been demonstrated in continuous, full-scale operation to yield a treated water meeting specifications established by the Pennsylvania Sanitary Water Board and containing excess alkalinity. Their final pH levels are usually less than seven, a condition which avoids consumption of excess neutralization reagents, but which occurs with lime-based processes and results from unwanted side reactions. Operating experience has been cited by Calhoun (4) using ferric waters while others (5), (6), (7), (8), (11), have reported on related research efforts. Despite the advantages including ?the relative simplicity, and minimal costs of the process, there have been very limited industrial applications of mine drainage neutralization with limestone. Although any treatment of these waters may be considered as a temporary control measure (9), the lack of feasible, immediate alternatives, the extensive magnitude. of the waters and the high cost of treatment requires that optimum processes should be utilized and that operating experience in their use be developed as is feasible. This paper will review treatment experience with a ferrous water of moderate pollution loading .

Jan 1, 1972

By Robert M. Cox

Surface mining of coal in the South developed into a major industry during the 1960's. The economic significance of the industry is much greater than is readily apparent when one considers only the value of the coal mined. The abun-dant supply of relatively inexpensive steam coal for electric power generation that has been derived from the surface mines has provided the foundation for the industrial expansion that has occurred throughout the South. The region, in gen-eral, has enjoyed the benefits of plentiful low cost electric power. However, re-cent political decisions, at all levels of government, threaten to destroy or severely curtail the surface mining of coal and eliminate the economic advantages once enjoyed by the region. These political decisions are rapidly changing the basic rules of operation and fundamental economics of surface coal mining. Recent changes, resulting from the enactment of environmental and health and safety laws and various bureaucratic rules and regulations, have had a three-fold effect: 1) Greatly increased operating cost, 2) increased lead times for mine development, 3) limited potential reserve base for future mining. Also current legislative proposals are casting a shadow of uncertainty over the future of all coal mining operations that has created serious delays and in-creased cost for the expansion of the coal industry necessary to meet our project independence goals. Technology Surface mining is the safest and most economical way to produce raw materials from the earth's crust. It also affords a more healthier working environment for the individual miner. Surface coal mining now accounts for more than 60 percent of the annual coal production in the South. Surface mining of coal requires the removal of the overburden to expose the

Jan 1, 1977

By Barry Hunsaker

I cannot help but be reminded, as I stand here today, of my boyhood years and heritage, both of which are inextricably tied to this very valley and are, in a: bay, apropos of the theme of this Keynote Session. I remember the scarcity of people. For example, 48, 000 in Phoenix and 436, 000 in the State in 1930 and 65,000 in Phoenix and 499, 000 in the State in 1940. Today Phoenix boasts a population of over 500, 000 and the State a population of 1, 500,000. I remember the' lack of facilities, goods and services, including gas and electric power. I recall stories of my grandfather who had the freighting or teaming contract to haul all the supplies and generating equipment, by wagon mind you, up the old Apache Trail to Roosevelt Dam. . .a three day trip from the nearest railhead which, by the way, was not Phoenix, for it did not merit a railhead on those days, but the village of Maricopa approximately 25 miles south of Phoenix. I remember chopping firewood, heating wash water on an open fire in a No. 3 wash tub at the rear of the house and doing my school homework by the light of a kerosene lamp just 25 to 35 years ago within what is now a large metropolitan area

Jan 1, 1965

By Robert A. Bauer

Introduction A longwall mining demonstration currently in progress in the Herrin (No.6) Coal Member near Benton, Illinois, involves the extraction of three adjacent panels by the longwall method. The first panel was completed in May, 1977. The Illinois State Geological Survey is involved in this project for two reasons: (1) to detail the geology of the roof and relate the geologic features to the behavior of the roof during mining operations, and (2) to study the nature and occurrence of coal balls (carbonate petrifactions of peat) encountered during this demonstration. General Geology of Area The stratigraphic sequence of beds immediately above the No. 6 Coal in this area, ranging from oldest to youngest, is: gray shale (Energy Shale Member), black carbonaceous shale (Anna Shale Member), and argillaceous limestone (Brereton Limestone Member) (figure 1). In some areas of the mine, where one of these units may rest directly on the coal, one or more of the members is absent from the stratigraphic sequence. The nature of roof for the area is shown in figure 2. It is greatly exaggerated in the vertical direction. The Walshville Channel, 11.3 km west of this mine, was a river at least in part deposited at the same time as the coal. The gray shale wedge on top of the coal, which thins away from the channel, is thought to represent an overbank deposit of mud from the channel. The next layer deposited on top of the gray shale, and on the coal not covered by gray shale, is the black carbonaceous shale, believed to represent a mud deposited in a brackish environment. The area where the roof lithologies change rapidly from one shale to

Jan 1, 1977

By D. A. Robbins

The application of remote sensing for environmental measurements is already being utilized. Aircraft mounted imaging spectroscopy has been utilized to evaluate areas of historical mining operations as well as active mine sites. To the extent that remote sensing can provide more sensitive, cost effective, and timely monitoring potential, the technology is of interest to the industry. Questions remain about the application and validation of the data and the availability of the technology in the private sector. This presentation will discuss some of the potential uses, benefits, and concerns related to remote sensing and efforts to monitor the technology's development.

Jan 1, 1999

By W. A. McKinney

The U.S. Bureau of Mines, Kennecott Copper Corp., and New Mexico Institute of Mining and Technology are cooperating on a research project to improve extraction of copper from previously leached waste dumps that are in part compacted and impervious to leach solutions. The field work is being done at the "J" leach dump, Chino Mines Division, Kennecott Copper Corp., Santa Rita, N. Mex. The laboratory percolation leaching tests were made at the U.S. Bureau of Mines Salt Lake City Metallurgy Research Center on drill core samples from the "J" dump to determine how much copper might be leached if permeability could be restored by explosive heaving or other means. The core samples from nine drill holes on "J" dump contained from 0.06 to 0.14 percent copper. Copper extractions ranging from 15 to 3 percent were obtained in 75 days by percolation leaching of minus-1-inch material with dilute sulfuric acid. The tests results indicate that about 2'7 percent of the copper remaining in the "J" dump could be extracted under ideal leaching conditions.

Jan 1, 1970

By J. F. T. Agapito

Two flat-lying trona seams 3-to 3.5-m thick, approximately 10 m apart, and at depths of 250 m are mined by room-and-pillar at OCI's Big Island Mine in Wyoming. Continuous miners and a yielding pillar system have contributed to improvements in resource recovery and productivity. Long-term stability with minimal subsidence is needed for a large portion of the mine beneath the Green River channel. This was investigated by computer modeling in 1990. Although results of the study indicated good long-term stability, recommendations were made for stress determinations to verify the model. Stress determinations made in 1997 showed pillar stresses 10% to 20% higher than the model stresses, and barrier pillar stresses 10% to 15% lower. This implies that higher panel stresses will be transmitted from the upper to the lower seam. A stability evaluation of the lower seam is planned before two-seam mining to assess entry widths and support requirements.

Jan 1, 1999

By V. Králová

The TESCAN Integrated Mineral Analyzer (TIMA), an automated mineralogy system, enables fast and quantitative mineral analyses of rocks, ores, concentrates, tailings, leach residues or smelter products. It combines BSE and EDX analysis for identification and measurement of mineral concentrations, particle size distribution, and liberation/locking parameters. In addition, it can provide bright particle searches for PGM, gold-silver ores, and/or REE. With the newly developed Automated Loading System (AutoLoader), the TIMA has become the world?s first automated mineral analyzer which permits robust, continuous and unattended sample loading. With the AutoLoader (robotics) system, the TIMA has emerged as a powerful plant support instrument. It increases the sample throughput, minimizes manual labor and enables 24/7 operations. As such, it can be used in daily, continuous mineralogy for mine geology/ore control, concentrators, leach operations, and smelter support. It will also increase the capabilities of technical service centers for mining companies, commercial laboratories, large drilling programs or pilot test campaigns. In combination with a highly automated sample preparation lab (sizing, potting and polishing), TIMA technology can establish high-throughput and fast-turnaround automated mineralogy lab modules for mine-site production support.

Feb 23, 2014

Sandvik built its first stone crusher in 1896 and has since grown to become a world leader in mining equipment. ?We are the best in the world, and we can now be even better at making our cone and jaw crushers in different models,? Olle Lundberg, production engineer at the Sandvik Mining factory in Svedala, Sweden told freelance journalist U. Samuelsson, of mekpoint.com. As a specialty manufacturing business under the umbrella of the Sandvik Group, Sandvik Mining is a leading global supplier of equipment, tools, services and technical solutions for the mining industry. Its expertise covers the areas of rock drilling, cutting and crushing, as well as loading, hauling and the handling of materials. Lundberg, along with five colleagues, will write CNC programs for the lathes and machining centers that manufacture Sandvik?s specially constructed casting. In 1999, Sandvik chose ESPRIT computer-aided-manufacturing (CAM) software by DP Technology to program its array of machine tools, and has worked with ESPRIT reseller Holotech, based in Örebro, since 2003.

Jan 1, 2014

By Jerome A. Westphal

The Middle Mississippi River extends from the mouth of the Ohio River to the mouth of the Missouri River, a distance of about 310 kilometers (km) measured along the river. From its founding in 1764 to the first steamboat arrival in 1817, the City of St. Louis was little more than a trading post. However, with the advent of the shallow-draft steamboat, the Middle Mississippi River rapidly became a major thoroughfare of commerce. In this regard, its importance has been reflected by the development of port facilities at St. Louis and by Federal activity relating to channel maintenance and improvement. First Federal work on the Middle Mississippi River was autho¬rized by Congress in 1824. This work was for snag removal and bank clearing and was directed at reducing the hazards to steamboat traffic, particularly during low-flow periods. During the 1820's and early 1830's, the main channel threatened to move toward the Illinois shore and abandon the St. Louis port facilities. In 1836 and 1837, Congress authorized construction of permanent improvements to keep-the river next to St. Louis (Missouri shore). By 1880, it was recognized that bank clearing activities had resulted in a wider and shallower river which exacerbated navigation

Jan 1, 1977

By S. K. Kawatra, J. A. Halt

"INTRODUCTION Iron ore beneficiation needs advances in areas such as process control, automation, burner and furnace designs, silica-free binders, and even alternative iron making routes. While some – like new binders – are only step-changes, all are tools that can help make the ironmaking industry more sustainable. This paper focuses on binders. Binders are added to iron ore fines before they are agglomerated. Binders are used to control the balling process and increase the mechanical quality (e.g. strength) of green-balls and pellets. Agglomeration usually follows thickening and filtration. Good-grade ores, which don't require upgrading, are wet ground to decrease particle size and increase specific surface area. Low-grade ores are often extensively upgraded through wet operations (flotation, dispersion and selective flocculation, magnetic separation, etc.). For both types of ores, thickening and filtration conclude the circuits so that moisture contents are lowered and the ores can be agglomerated. It's been known for a long time that thickening and filtration behaviors are influenced by zeta potential (Sandvik, 1979). Highly-negative zeta potential is good for dispersion while low zeta potential is good for filtration. So, the zeta potentials of iron ore particles are lowered with additions of acid or carbon dioxide, for example, to increase filtration rates and throughputs (Eisele et al., 2005). What happens to particles as their zeta potentials are lowered? Particles aggregate together, effectively forming larger particles. How stable then, are those aggregates during mixing and balling? Are they easily broken up during mixing (if mixers are even used)? Are they broken up during balling? Or, do the aggregates resist breakage so that the availability of ultra-fines, which are so beneficial for agglomeration (Stone, 1968), is decreased? For plants where high doses of bentonite are used as binder, the above questions may be of no concern. The bentonite adds the necessary amount of fines; however, even at those plants, the calcium and magnesium contents in the water affect bentonite's effectiveness (more magnesium and calcium means less effective bentonite). (Engesser, 2003) For plants where new silica-free organic binders are being developed and used, the above questions may need to be considered. The binder is only amongst the iron ore particles for a short period of time – until it burns away or thermally decomposes in the induration furnace – so the liberation, availability and distribution of fine particulates is very critical for the quality of balls and pellets. It was hypothesized that high zeta potential conditions would lead to good pellets, while low zeta potential conditions would lead to relatively bad pellets."

Jan 1, 2018