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By K. Lang

The use of high-efficiency electrical submersible pumps (ESPs) for large scale, open pit mine dewatering operations provides a good example of how technology, products and services from the oil and gas industry can be adapted to the mining industry. In this case, the mine is Goldcorp?s Peñasquito in the Zacatecas state of Mexico, at the Peñasco and Chile Colorado open pit deposits. The technology, products and services are from Schlumberger artificial lift (AL) and Schlumberger industrial water services (IWS). Overview of high-efficiency ESPs This section provides a brief description of the basic components, specifications and operating capacity ranges for the ESPs compared with traditional or conventional dewatering well pumps. This information helps to establish how ESPs provide certain functional and economic advantages over conventional pumps in a mine dewatering application. A schematic of a high-efficiency ESP in an oil and gas (O&G) application is shown in Fig. 1.

Sep 1, 2013

By Edwarde R. May

The Flambeau volcanogenic massive sulfide deposit located in northwestern Wisconsin occurs within the southern lobe of the Canadian Precambrian Shield. The steeply dipping tabular body occurs in a complex pile of cyclic schistose intermediate to felsic fragmental volcanics. No chloritic alteration pipe is recognized but adjacent rocks have undergone magnesia metasomatism and subsequently were metamorphosed to the upper greenschist and lower amphibolite facies. Although modest in size the deposit is of special interest in that it has an extensive and well preserved supergene enrichment blanket. Economic minerals found within a pyritized quartz-sericite schist are chalcocite and bornite overlying primary chalcopyrite.

Jan 1, 1976

By Lim Thi Duong, Du Duy Bui, Thuat Ngoc Pham, Chuc Ngoc Pham, Que Anh Nguyen, Hoa Anh Bui, Chi Thi Ha Nguyen, Hoan Thanh Nguyen, Bac Quang Nguyen, Kien Trung Nguyen, Dung Trung Doan, Nhiem Ngoc Dao

The microstructures and kinetics of a rich iron ore ( TFe = 65.84%) of Na Rua mine, Vietnam, used for the iron production were investigated in this study. Thermal behaviors of iron ores were well-examined by heating microscopy, thermogravimetric analysis, and differential thermal analysis. After being pelletized and then oxidatively fired at 500–1200 °C for 2 h, the pellets fired at 1200 °C (P1200) displayed a hard and dense structure with a decent compressive strength of 317.9 kg/pellet whereas those fired at 500 °C (P500) had a soft and spongy structure. The reduction of iron pellets conducted in a flow of a 60–100% CO2/ Ar gas mixture at 900–1100 °C showed significantly higher efficiency than the reduction using coal. The spongy pellets showed superior performance for the reduction in the CO/Ar gas mixture compared to the dense ones, compatible with the production of sponge iron. When mixed with an amount of coal, P1200 designed for iron production in the blast furnace demonstrated an impressive reduction activity compared to P500 and previous studies. The kinetics of pellet reduction was determined by the diffusion of substances through the solid product layers having the mathematical model of 1 − 2 3 f − (1 − f )2∕3 = kt . The microstructures of pellets during the oxidative firing and reduction were also examined by X-ray diffractometry; scanning electronic microscopy; energy-dispersive X-ray spectroscopy; and Brunauer, Emmet, and Teller method.

Jun 7, 2022

By Jerry M. Whiting

Greater awareness of the increasing need to develop supplementary energy sources is accelerating us towards many basic decisions regarding future utilization of mined energy materials -- uranium, coal, oil sands and oil shale. The latter material comprises a major potential source of oil which will require creation of unusually large and low-cost underground mining systems. In this paper, the author briefly outlines and analyzes several of the factors which continue to provide the somewhat unique character of oil shale nine planning and mine operation.

Jan 1, 1974

By Dominick Mandalari, David Mast, Heather Ullinger, Juan Granja, Amanda Foote

The City of Akron will construct the Northside Interceptor Tunnel project, a U.S. EPA/ DOJ CSO Long Term Control Plan Project. The system will provide at least 10.3 million gallons of storage in a 16.5-foot finished ID and 6,660-foot-long rock tunnel. The system will reduce both overflow volume and number of overflow structures on the Cuyahoga River. The project includes deep drop shafts and more than 3,000 linear feet of 48 to 96-inch I.D. sewers installed by trenchless construction methods. This paper will discuss the project background, ground conditions, and other challenges overcome during the design phases.

Jun 13, 2023

By L. F. Zeiler

In the past, health concerns in coal mines have primarily centered on those elements which have been essentially inherent to the mining environment. These would include respirable coal mine dust, respirable crystalline silica, excessive noise levels, and diesel exhaust particulates. Commercially-available chemical products are prevalent on mine property. These potentially toxic materials are chemical formulations that can degrease, clean, and lubricate metal parts, separate coal from rock in float/sink operations, and aid in roof consolidation, among other uses. As the general public has become more aware of the hazards of chemical exposures, miners have likewise become more concerned about working with an ever-expanding variety of chemical products on the job. Often, product or chemical specific hazard communication training is inadequate or ineffective, and miners do not know exactly what the ingredients are in the products they handle, or the health hazards involved with their use or misuse. Currently, the Mine Safety and Health Administration (MSHA), by law, enforces 1972 Threshold Limit Values (TLV). MSHA is making preparations to adopt new personal exposure limits for enforcement. The values given throughout the article are 1994 TLV's and are not enforcement standards, but are used for discussion purposes. They reflect the current scientific thinking regarding personal exposure to these chemical agents. An overview of these products is presented, and the potential health hazards associated with their use are discussed. Controls needed to prevent overexposures, such as proper handling procedures and personal protective equipment, are covered. Methods used to collect and identify contaminants are presented.

Jan 1, 1995

By Stephen M. Voynick

Two hours driving time west of Denver, CO and 21 km (13 miles) north of Leadville, Bartlett Mountain rises 4,065 m (13,337 ft) high in central Colorado's Tenmile Range. Bartlett Mountain is one of Colorado's most recognizable peaks, especially when the late afternoon sun casts a surreal, reddish light across its most prominent feature - the Glory Hole. This is a gaping, half-mile-wide, 245-m- (800-ft-) deep crater. Created by subsidence from 60 years of massive underground mining, the Glory Hole is a monument to the Climax Mine, one of the great achievements in American mining and metallurgy. For most of this century, the name Climax has been synonymous with brilliant mining engineering, innovative metallurgical research and entrepreneurial promotion of a once-obscure metal - molybdenum. Climax overcame an array of economic, technological and social problems to become a model for underground development of massive deposits of low-grade ores. It is one of the few mines in the world where cumulative production is measured in the billions of dollars. The Climax mineralization was emplaced 30 million years ago. Magmatic intrusions formed a large, mineralized stockwork within the granite country rock of Bartlett Mountain. Associated hydrothermal events forced superheated metal- and quartz-rich solutions through fracture zones, silicifying the country rock and depositing huge amounts of molybdenite, or molybdenum disulfide. The mineralized rock, a light gray, finely crystalline, silicified granite, is laced throughout with blue-gray quartz veinlets containing molybdenite. Although the richest ores graded only about 1% molybdenite, the Bartlett Mountain deposit contained more than 2.7 Mt (3 million st) of elemental mo- lybdenum.

Jan 1, 1997

By Paul O. Knorr

The Bureau of Ocean Energy Management (BOEM), a bureau within the U.S. Department of the Interior, has responsibility over both energy and non-energy mineral development on the United States Outer Continental Shelf (OCS) under the OCS Lands Act (“OCSLA”). BOEM’s Marine Minerals Program (MMP) manages federal offshore mineral deposits through non-competitive, negotiated agreements for sand and gravel (“sand”) used in coastal restoration efforts and the competitive leasing of critical and hard economic minerals (“critical minerals”). As the steward of OCS critical minerals, BOEM MMP is responsible for understanding where critical minerals are located, identifying and understanding their environments, managing activities that affect these resources, and implementing pertinent federal policies. Fulfilling these responsibilities involves the collection and analysis of environmental, geological, and geophysical data; supporting the science needed to understand the impacts of resourcerelated authorized activities on the biological, physical, and sociocultural environments; encouraging emerging technologies that can reduce the environmental impact of activities; and communicating with stakeholders to foster an understanding of existing federal regulations and potential needs to revise the legal framework. Four U.S. federal rules in the Code of Federal Regulations (CFR) currently inform MMP’s procedures: 30 CFR 580 (prospecting for minerals), 30 CFR 581 (leasing of minerals), 30 CFR 582 (operations in the OCS related to minerals), and 30 CFR 583 (negotiated noncompetitive agreements for sand). Other federal laws and regulations are also pertinent, particularly those supporting the National Environmental Policy Act, Endangered Species Act, National Historic Preservation Act, Marine Mammal Protection Act, Coastal Zone Management Act, Clean Air Act, Federal Water Pollution Control Act, and Magnuson Stevens Fishery Conservation and Management Act.

Feb 22, 2026

By Walter von der Linden

On April 14, 1975, Consolidation Coal Company began to operate a longwall face in their Shoemaker Mine using shield supports. This was the first time that shield supports were used in the United States (1) 1/. Shortly thereafter, Kaiser Steel Corporation started a shield longwall face at their York Canyon Mine (2). From October 1975 through May 1976, three more longwall faces were commissioned in mines located in south-western Pennsylvania and northern West Virginia. In June 1976, four installations had completed their first panel and two installations had completed the subsequent move to the second panel where coal production is now well under way. During this time (April 75 to June 76) the total number of shield support face operating months, including moving time, was 40 and the combined face advance was approx. 17, 000 feet (5200 m) with face lengths varying from 450 - 550 feet (137 - 168 m). While the shield support experience in the U.S. is still limited on the basis of time and mining parameters, the operating results of all faces have been very satisfactory. New record 24 hr production figures were set and - far more important - long term production figures could be sustained on an impressively high level even when taking face moving time into account. The purpose of this paper is to review the performance of shield type supports in the U.S. and to assess their value as longwall supports for U.S. underground mining conditions with regard to roof control, maintenance, operator convenience, safety and productivity.

Jan 1, 1976

By Arnold Dix, Oliver Heger, Bernhard Kohl

In the USA, risk-based decision making has not been a common approach to tunnel safety in the past, but this is changing, as concepts such as “equivalency” in the NFPA 502 framework gain acceptance in the USA and elsewhere. In other regions, in particular in Europe, risk assessment techniques have been used for nearly two decades in many jurisdictions as an additional tool to complement the application of prescriptive guidelines and support decisions related to tunnel safety. After some initial difculties these methods are meanwhile a well-established element of tunnel safety management. There are several tools available which have been practically applied and further developed over years, such as the Austrian tunnel risk model TuRisMo, or the PIARC owned DG-QRAM model. Whereas TuRisMo is a holistic, system-based model, which is best suited to quantify and assess re risk and associated mitigation measures, DG-QRAM focusses on the risks related to the transport of hazardous materials. Depending on the objectives and the scope of the investigation and the regulatory environment tunnel risk assessment tools are in use for different purposes, mainly to demonstrate a sufcient level of safety and to decide on and select additional risk mitigation measures. The international eperience substantiates that the general approach is eible and that the methods and tools are mature and can be applied for different problems in different environments. First case studies like the risk study on conditions and permissibility of the transport of hazardous materials through the Eisenhower-Johnson-Memorial Tunnel in Colorado demonstrate the applicability of a risk-based concept for decision making in the US-American environment.

Jun 23, 2024

By R. P. King

Knowledge of the behaviour of flotation machines had developed and increased considerably over the last few years. Although much work remains to be done on the study of the fundamental processes that influence the collection of hydrophobic particles at an air-water interface, there is enough information to permit the building of realistic models of the gross flotation behaviour of various ores. These models serve as an ideal base for the development of simulation techniques for the steady-state behaviour of entire flotation plants that consist of a large number of individual flotation machines. Simulation techniques have a very real role to play in assisting with the design of new plants and in improving the operation of exisiting plants. Recently, highly efficient data-logging systems have been introduced on flotation plants. These systems are based on the on-line measurement of volumetric flowrate, pulp densities, and metal contents, and they generate enormous quantities of information regarding the operation of the plant. Unfortunately, this information is largely wasted at the present time because efficient data-reduction techniques, although available10 are not in common use. Simulation techniques play a central role in such data reduction because they form the essential link between the fundamental kinetic flotation processes on the one hand and the plant data on the other.

Jan 1, 1974

By C. S. Thompson, P. A. Ciullo

Pyrophyllite is a naturally occurring hydrous aluminum silicate with the molecular formula SiO,,AI,,(OH), or, as more commonly expressed, the oxide formula A120,~4Si02~H20. Pyrophyllite is rarely found in deposits as the pure mineral and is often intimately associated with quartz, sericite, kaolinite, and diaspore. These associated minerals, to a large degree, help determine the most appropriate commercial application for a given pyrophyllite ore. Structural similarities plus the generally soft platy nature of pyrophyllite has in the past caused it to be included with talc in applications and production data. The Minerals Yearbook, published annually by the US Bureau of Mines (USBM), still reports on talc and pyrophyllite together, although admitting that they do not share the same uses. Pyrophyllite has also at times been considered a clay mineral because of its structure and chemistry. The refractory properties of pyrophyllite have been known for nearly 200 years, but it has only been in the past 60 to 70 years that a variety of applications have been developed to exploit the unique characteristics of this mineral. Worldwide, pyrophyllite is a component of refractories, whiteware, foundry mold dressings, pesticides, paint, plastics, rubber, cement, fiberglass, and soap. Historical Overview The most salient refractory features of pyrophyllite are its low coefficient of thermal expansion, high thermal conductivity, low moisture expansion, and good resistance to corrosion by molten metals and basic slags. One of the first recorded uses of this mineral was as firebrick in Japan in the early 1800s. This followed its discovery in 1797 on Mount Omotoyama at the site of the present Mitsuishi mine. In addition to firebrick, sawn blocks of ore were used for carvings and in the manufacture of slate pencils and signature seals. The Mitsuishi mine is still one of Japan's largest. By the mid-1800s, refractories were being made in Japan from roseki (a pyrophyllite-bearing ore) for the construction of metal melting furnaces. The mineral did not get its name until 1829 when R. Herman, testing a sample of supposed talc from the gold-quartz veins at the Berezovo deposit in the Urals, showed that it was actually an aluminum silicate and designated it pyrophyllite. This name was derived from the Greek pur for fue and phullon for leaf, in allusion to the effect of heat in causing separation of the laminae in foliated varieties (Mellor, 1927). The exact date of the discovery of pyrophyllite in the United States is uncertain, but it is believed that the talc and soapstone deposits noted in an 1827 report on the geology of the slate belt of North Carolina were actually pyrophyllite occurrences (Olmstead, 1827). Pyrophyllite was first used in North Carolina on a local basis in the early 1800s. Blocks were sawn and cut for use as stove linings, mantels, chimneys, fireplaces, and gravestones. This was the material of choice because it did not shrink when heated, but cut easily and hardened as it weathered. Pyrophyllite crayons were sold commercially by local gold miners for steel marking and as tailor's chalk from about 1800 until 1922. It was during this period that pyrophyllite was discovered near the town of Hemp (later renamed Robbins), NC. The large quantity of scrap resulting from the sawing of crayons at this deposit prompted the construction in 1921 of a grinding plant. The ore scrap was ground to fine granules and sold to asphalt producers to prevent shingles from sticking together. By the mid-1930s, milled pyrophyllite from North Carolina was also being successfully utilized by the ceramics industry in whiteware for its low cost and ability to shorten firing time. Also during the 1930s, pyrophyllite was first used in kilncar furniture in the United States. Canada was another early entrant in the pyrophyllite business. Mining at the Foxtrap deposit on the Avalon Peninsula of Newfoundland began in 1904, with ore shipped to the United States. Production from this deposit was mostly sporadic in the ensuing years until 1956 when mining began for shipment and captive use in US tile manufacture. This production has remained continuous and still essentially captive to the present. The Foxtrap deposit is currently the sole commercial source of pyrophyllite in Canada.

Jan 1, 1994

By A. T. Iannacchione

Unfortunately from 1991 through 1995, 44 miners were fatally injured in the stone industry. Of these 12 occurred at underground mines from a total work force of less than 2,000 miners. Nine of these 12 miners were fatally injured in falls of roof or rib. A safer environment for the miners can be achieved by evaluating the nature of the hazardous ground and by developing more efficient and effective ground control strategies. Roof and rib conditions in the underground stone industry were observed and assessed at 33 mines in Illinois, Indiana, Kentucky, Maryland, Missouri, Pennsylvania, and West Virginia (Figure 1). Hazard assessment indicated that those ground failures occurring under moderate to substantial overburden ( > 30 m [100 ft]) were caused by stress concentrations and geologic structures. Ground failures near the surface are caused by solution (water) processes. Selection of the mining horizon and mine layout decisions tremendously influence ground stability.

Jan 1, 1997

By R. L. Thoms

Compressed air energy storage (CAES) has been initiated recently in West Germany with a 290 MW peaking-power facility utilizing twin cavities with volumes of 150,000 m3 each in the Huntorf salt dome (1). The implementation of CAES in several geologic media is being studied carefully in the United States (2); however, the use of cavities for CAES in salt domes or salt anticlines and the associated long-term stability of these cavities is the specific topic of this paper (3). The cavities represent an essential element in a CAES plant, and thus should be designed and operated to perform with "stability" over the planned life of the overall facility. As employed herein, cavity stability implies the extent to which an acceptable amount of cavity storage volume can be utilized with economic maintenance over the planned life of the overall facility. In this sense stability is relative to the planned use of a storage cavity. Figure 1. depicts the salt deposits of the United States (U.S.) (4). The Gulf Coast region includes the only confirmed salt dome basin in the U.S., although salt structures also exist as anticlines in the Paradox Basin of Utah and Colorado. Because of the relatively small amount of elevation change within the Gulf Coast, CAES in salt dome cavities appears to hold considerably more potential for energy storage in this region than more traditional "pumped hydro" systems.

Jan 1, 1979

By O. J. R. Baena, N. J. Zapata

In Colombia, more than 15 regions and around 100 municipalities develop gold mining at different scales, and these operations generate mining waste composed of processing fluids and crushed rock with metals and high silica content. Cement production requires clinker, gypsum and other corrective additives. Clinker results from the partial fusion of some minerals including silica. In this study is proposed to evaluate the effect of the use of mining tailings sands from gold mining in the manufacture of clinker. The proposed methodology will allow the characterization of the sands to manufacture a cement specimen and measure its physical and fire properties

Mar 2, 2022

By S. S. Sephton

The La Perla Mine, owned by Altos Hornos de Mexico, S.A., is located approximately 100 miles east of the City of Chihuahua in the State of Chihuahua, Mexico. The mine began operations in 1958. Existing ore beneficiating facilities, consisting of heavy media and jig plants, upgrade the ore prior to shipment by rail to the Altos Hornos steelmaking complex in Monclova. Sizable reserves of two distinct ore types, which were not amenable to treatment in the existing beneficiating plant, or usable in the blast furnaces, have been mined and stockpiled in order to uncover the treatable ores. One of these ore types has been labeled "Diseminado" ore, and is low grade containing approximately 42% Fe with sulphurs ranging from 1 to 2%. The other ore type has been labeled "Pulverulento" ore, and is high grade containing approximately 65% Fe and 0.1% S, but at 80% minus 325 mesh, is too fine grained for efficient sintering. Late in 1968, Arthur G. McKee & Company became involved with the problem of improving the above ores for their efficient and economical use in Altos Hornos' blast furnaces. Early in 1969 representative samples of Diseminado ore were obtained for laboratory bench-scale testing at the University of Minnesota, Mineral Resources Research Center. Concentration tests incorporating magnetic roasting, wet magnetic separation, high intensity separation, high tension magnetic separation, anionic flotation of apatite, cationic flotation of silica and oleic acid flotation of iron were performed. Laboratory testing was concurrently carried on at La Perla Laboratory, which resulted in plans to construct a 10 TPD pilot plant. The pilot plant was operational in September, 1969. Analyzing laboratory results as well as pilot plant results, Altos Hornos and Arthur G. McKee & Company metallurgists agreed that the most promising flowsheet for the low grade Diseminado ores entailed wet magnetic cobbing, desliming, and oleic acid flotation of the non-magnetic fraction. A combined concentrate of

Jan 1, 1972

By P. McGrath

From the mid-1980s through 1997, Echo Bay Alaska evaluated reopening the historic Alaska-Juneau (AJ) gold mine. Their original proposed project underwent numerous modifications in order to minimize the potential for significant environmental impacts. One of the major modifications involved changing .the tailings disposal method from a conventional tailings impoundment to submarine tailings disposal (STD). In 1995, the U.S. EPA began work on a Supplemental Environmental Impact Statement (SEIS) to assess the impacts of the STD proposal. Key features of the STD impact assessment included fate and transport modeling to determine the extent of tailings deposition and the use of ecological risk assessment to predict marine impacts during deposition and ecosystem recovery following STD. A key feature of the SEIS regulatory process included a rulemaking proposed by EPA to exempt the AJ tailings from effluent regulations. Critical to success in moving the project forward was early development of an interactive working relationship with other regulatory agencies and the public.

Jan 1, 1998

By Joseph W. Mullan

The today status of air pollution control legislation and regulations can best be described as an exaggerated state of environmental limbo. The '70's began but one and one-half months ago yet it already has been very appropriately named "the decade of the environment." This certainly will be the decade for new legislation - new regulations and hopefully "Clean Air." Already Washington is faced with legislators playing "pollution politics" to the crowds. Students have redirected their efforts from Vietnam to the cleansing of the environment and everyone including the man on the street has become an environ¬mental expert. This is the decade we all face, but where are we today? Pollution is not a new problem. It has been with us for centuries and while much is left to be done, much has already been accomplished. I will try to make some comparisons of what I believe to be the good and bad points in the national air pollution control picture and hopefully will generate within each of you sufficient concern as to which comparisons are sound.

Jan 1, 1970

By S. Mojeddifar, N. Ostadmahdi Aragh, M. Hemmati Chegeni

This work integrated selective principal component analysis (SPCA) with a singularity fractal model to map hydrothermal alterations of argillic, phyllic, and propylitic in the north-west of Kerman city in Iran. SPCA results were provided for short wave infrared (SWIR) bands of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor tomap phyllic and propylitic alterations. Also, the bands 5–7 were applied to map the argillic alteration zone. SPCA results could present useful information for alteration mapping but it does not show the purest pixels of alteration. Therefore, a fractal model of singularity was applied to highlight the different alteration pixels in the Kerman Cenozoic magmatic arc (KCMA). Thus, the singularity index of different hydrothermal alteration zones was produced. Comparing the obtained results with the field data showed that Kader, Serenu,Meiduk, and Abdar deposits were acceptably identified by alteration mapping. Also, it seems that the singularity index could not discriminate the hydrothermal alterations of argillic and phyllic. The same spectral signature of kaolinite and muscovite minerals is the main reason for misclassifications.

Jul 20, 2020

By William C. Dixon

Since the mid 60's, several haul cycle simulation programs have been developed. However, most of these programs are believed to employ the continuous, rather than the discrete, event-oriented simulation approach to determine the haul cycle times. This paper describes the recently developed haul cycle simulation approach where time is advanced in varying amounts only as the system changes occur. This approach results in greater computational accuracy and increased computational efficiency. The program is written in FORTRAN and requires equipment performance curve and haul road profiles as input. Unique program capabilities include the handling of switchbacks and intersections. The program uses a master data file concept in which various haul road profiles found during the mine life can be simulated all in one job submission. The results of the model validation using the actual time study data provided by an open pit mine operator near Tucson, Arizona, are also described in this paper.

Jan 1, 1978