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By K. A. Allison, D. R. Van Orden, R. J. Lee

Continuing analysis of environmental samples for asbestos content has resulted in the misidentification of non-asbestos amphibole particles as asbestos fibers. These errors have received wide publicity (such as in the asbestos-in-crayon story) and have caused unnecessary reformulation of products. The primary cause of these errors has been a poor understanding of mineralogy and analytical techniques among the many asbestos laboratories that arose following the passage of the AHERA regulations. Presented here is a procedure based on published data that can be used to correctly classify an elongated particle as asbestos or as non-asbestos.

Jan 1, 2005

By T. Johnson

Mining activity in a number of metal ores has been running quite high over the last few years. In particular, those metals that employ acid functional extraction processes such as copper, nickel, cobalt and uranium have been particularly active. The world?s largest nickel mine ? the massive $4.76 billion Ambatovy nickel mine on the African island nation of Madagascar is nearing completion. When it reaches its full production capacity in 2013, the mine will produce 60,000 MT/yr of nickel and 5600 MT/yr of cobalt. Coming on the heels of the Ambatovy project is the Long Harbour Processing Plant in Newfoundland, Canada which will process the ore from Vale?s Voisey Bay mine in Labrador. Voisey?s Bay is expected to generate more than 50,000 MT/yr of nickel ore when it starts up in 2013. Next up will be the Boleo project in Mexico on the Baja peninsula. When commissioned in 2013, the $1.4 Billion Boleo project is expected to produce 60,000 MT/yr copper, 3100 MT/yr cobalt, 36,000 MT/yr zinc and 100,000 ? 250,000 MT/yr manganese carbonate.

Feb 27, 2013

By W. J. Miles

At the beginning of the 20th century, barite was a mineral of minor importance in the United States. Its primary use was to extend lead oxide in white paint. Barite also added the special qualities of hiding power and flatness to paint. Because white lead sometimes turns black or yellow and barite does not, ground barite became a pigment on its own merit. Barium chloride was added to bricks before fi ring to stop efflorescence when exposed to weather. Barium carbonate or nitrate added luster and brilliance to glass. Barium chemicals were added to refining sugar, enameling iron, making oilcloths and paper collars, and in the manufacture of paper, artificial ivory, rubber and lithopone. Lithopone became a major paint ingredient in the 1920s; its use lasted until the 1950s, peaking at 150 kt (165,000 st) of barite in 1937 and 1947 for the manufacture of lithopone. Later in the 20th century, titanium dioxide replaced lead oxide, barite and zinc oxide in the coatings industry. In the 21st century, barite is used as a filler, extender or weighting agent in products such as paints, plastics and rubber. Some specific uses include its use in brake and clutch pads for automobiles, automobile paint primer for metal protection and gloss, to add weight to rubber mud flaps on trucks and to add weight to the cement jacket around petroleum pipelines under water. In the metals casting industry, barite is part of mold release compounds. Because barite significantly blocks X-ray and gamma ray emissions, it is used as aggregate in high density concrete for radiation shielding around X-ray units in hospitals, nuclear power plants and university nuclear research facilities. Ultra-pure barite consumed as liquid is used as a contrast medium in medical X-ray examinations. Barite is the raw material for barium chemicals, such as barium carbonate, which is an ingredient in faceplate glass in the cathode-ray tubes of televisions and computer monitors. In the 21st century, barite industrial uses accounts for an estimated 78 kt/a (86,000 stpy) in the United States.

Jan 1, 2009

By Ivo Dreiseitl, Kondratenko. Anatoly

"The second prime area within the Interoceanmetal Joint Organization exploration area named H22 was delineated in 2013 with the goal to ensure sufficient nodule reserves for profitable mining operations and processing.The knowledge base for area H22 has been obtained from archive materials. The geological situation can be characterized as follows: the sea bottom is represented by tectonic blocks oriented in a sub-meridional direction. According to swath mapping, the depressions (troughs) are contoured at depths of 4500-4600 m while the tops of horsts occur at 4300-4350 m. Volcanic relief occupies 6% of the H22 area; in the eastern part a multicone volcano was detected. Its area at the base is 153 km2. The maximum height of a cone above the base is 850 m. The crystalline basement composed by tholeiitic basalts of late Oligocene age is covered by about 100 m of sediments. Semi-consolidated to consolidated calcareous nanofossil sediments of the Marquesas formation are deposited on the basement. Higher up in the profile sediments of the Clipperton formation occur. They are represented by unconsolidated siliceous (Radiolaria, Diatom) ooze. Sediments containing calcium carbonate have not been detected. Where opaline silica (or CaCO3 if any) content is below 5%, the sediments belong to zeolitic clays or red pelagic clays. Grain size composition of the seabed and the near-seabed sediments in H22 classifies them into clayey silts."

Sep 1, 2014

By David Hake, David Salisbury

The Drainage Services Department (DSD) of the Hong Kong SAR Government commissioned the design and construction of the West Kowloon Drainage Improvement, Stage 2, Phase 2, Kai Tak Transfer Scheme (KTTS) project in 2000 to relieve potential flooding in Mong Kok caused by the insufficient capacity of the existing storm water drainage system. The KTTS involves construction of a 1.5km,4.4m drainage tunnel and a 450m long box culvert, running from Waterloo Road near Hereford Road to the existing Kai Tak Nullah in San Po Kong. This paper describes the design and construction of; the bored tunnel through both hard rock and soft ground using a slurry Tunnel Boring Machine (TBM), six associated access shafts, a connection structure at Waterloo Road and the box culvert connecting the bored tunnel to the outfall at Kai Tak nullah. Details will be provided on the contractor’s alternative designs adopted during the contract including the use of fibre reinforced shotcrete as one-pass temporary and permanent support for three of the shafts and modifications to the Engineer’s design for the box culvert structure.

Jan 1, 2005

By Georgene Renner, William R. Yernberg, Steve Kral

ABB provides integrated pro-cess control, optimization and information systems, drives and power-distribution equipment as well as other services and support to the mining industry. ABB also supplies electrical equipment and control systems for the openpit mining industry. This includes products for the automation of electrical equipment in mine shovels. The company offers low- and medium-voltage drives for various mineral- industry applications. And ABB provides gearless mill drives for equipment, such as semiautogenous grinding mills that are too large for conventional drives. ABB Industrial IT provides innovative hardware and software systems that cover all the requirements of the modern mining and processing plant.

Jan 1, 2004

By Tim O’Neil

Dressed in black tie and Victorian attire, some 200 people came to Leadville, CO, for a September weekend featuring a National Mining Hall of Fame and Museum (NMHF&M) induction banquet and a scenic mountain train trip to Fremont Pass and the Climax Mine. The 18th annual induction banquet on Sept. 17 began with cocktails and a open house. It was a chance for visitors to tour the National Mining Museum including the new Hennebach Wing, opened in February. The new wing is named in honor of Ralph Hennebach, retired chairman of Asarco. Formerly Leadville Junior High School, the Hennebach Wing encompasses more than1,440 m2 (15,500 sq ft) of floor space in two stories. One prominent feature is a 1923 Wills Sainte Claire touring sedan. Climax Molybdenum donated this first all-molybdenum steel motorcar. Docents were available throughout the museum to give banquet attendees directions and answer questions.

Jan 1, 2005

By H. Lowers, P. Hageman, S. Diehl, D. Fey

Understanding relationships between mineralogy, texture, microstructural features, and element distribution and residence in minerals, is critical for accurate modeling of mineral weathering in waste-rock piles. The morphology of minerals and deformation structures, such as veins and faults, are important factors that control: (1) fluid access to the mineral surface to initiate dissolution, (2) the distribution of trace elements, and (3) formation of secondary minerals. We characterized the mineralogy, textures, and chemical properties of waste-rock material at three sites at scales ranging from outcrop to micrometer scale. A comprehensive hand-sample to thin-section scale methodology utilizing light microscopy, scanning electron microscopy, electron microprobe, and laser ablation ICP-MS was used to thoroughly characterize the waste-rock material.

Jan 1, 2007

By Morteza Gharouni Nik

Flexible Dilatometer Test (FDT) is one of the in-situ test methods for determining the deformational characteristics of rock masses. In this study, several dilatometer tests have been conducted in different geotechnical phases of site investigations by means of two types of FDTs. The purpose of this paper is comparison of the performance of these two types of dilatometers and analysis of the differences in the results of the tests.

Jan 1, 2008

Pillars in underground limestone mines are required to support the overburden and provide a safe, stable working environment for mining personnel and equipment. Pillar stability was assessed by the National Institute for Occupational Safety and Health in underground limestone mines in the Eastern and Midwestern United States. It was found that current mine layouts have been successful in providing support to the overburden, while a small number of isolated pillar failures were observed. The stable pillar layouts and failed pillars were plotted on a chart that demonstrates the relationship between pillar width-to-height ratio and pillar stress. The results show that pillar failures occurred at the lower range of width-to-height ratios and can occur at relatively low stress levels. Zones indicating the potential risk of pillar instability are shown on the chart, based on hazards associated with the onset of rib spalling, large angular discontinuities and unconfined pillars. The chart can assist limestone mine planners to evaluate potential instability in current or new pillar layouts that are similar to those included on the stability chart.

Jan 1, 2008

By Donald A. Ranta

Every mineral project or mine is based on a geologic entity-an ore (mineral) deposit. A well-defined mineral deposit and its associated geologic characteristics are the only aspects of a project that cannot be altered. Mine plans can be modified to exploit the deposit using alternative approaches and yielding similar results. A variety of processing methods also are often available producing generally comparable results. Major modifications can be made to other aspects of the project without substantially changing project economics. However, all engineering and metallurgical aspects of a mine must be accommodated to the spe¬cific location and geologic characteristics of the deposit. Geologic data and interpretations form the foundation for both mine evaluation and mine production by providing esti¬mates of reserves and essential information for mine planning and process design or control. Proper geologic work requires a keen awareness of and an ability to anticipate the technical requirements of geotechnical engineers, hydrologists, mining engineers, metallurgists, and other specialists. Geologists are inte-

Jan 1, 2008

By Helmut Westermayr, Michael Tergl

DESCRIPTION OF PROJECT Geographic Setting The Kops II plant is a pumped storage scheme of the hydroelectric power producer ‘Vorarlberger Illwerke AG’ which is currently under construction in the Austrian Province of Vorarlberg. The plant is located at the end of the Montafon valley and will be fed with water coming from the Silvretta mountain range (Figure 1) Description of Plant The Kops II plant shall be operated as a pumped storage plant with three highly flexible and quickly controllable power generating units. Each unit shall have a capacity of 150 MW and shall be equipped for both turbine operation and pump operation. The Kops II plant uses the existing Kops Lake as upper storage reservoir and the existing Rifa balancing reservoir as lower storage reservoir. All major plant components of the Kops II scheme are located below ground. Total investment costs areapprox. 360 million Euro. Construction Lots The construction works for the Kops II plant, which were subdivided into three lots, were launched in September 2004. It is planned that the first power generating unit shall go on line in the year 2007. The completion of the overall project and the operation start-up of the second and third unit are envisaged for the year 2008. Lot 1—Pressure Tunnel. The 5.5-km-long pressure tunnel forms the connection between the Kops Lake and the beginning of the pressure shaft. The tunnel was excavated by the use of a double-shield TBM. Lot 2—Pressure Shaft and Surge Chamber. The approx. 1.1-km-long pressure shaft was excavated by TBM, advancing from bottom to top. Featuring an inclination of80%, the pressure shaft overcomes a difference in height of approx. 700 m. Lot 3—Power House Cavern and Tailrace Structure. The power house cavern, which is being built approx. 150 m inside the mountain, forms the core of this plant. The power house is designed to accommodate three power generating units, and the transformer cavern is forseen to accommodate three transformer units. The tailrace structure serves the purpose of conveying the water to the lower storage reservoir during turbine operation and as water intake during pump operation (Figure 2).

Jan 1, 2007

By Brain E. Gombos

The Allen Park Sanitary Sewer Overflow (SSO) Tunnel and relief sewer project, located in the city of Allen Park, MI, is a long-term corrective action designed to bring Sanitary District One?s sanitary system into compliance with its 2005 consent order and service contract with the Detroit Water and Sewerage Department (DWSD). The $20 million project is intended to reduce Allen Park?s wet weather discharges to DWSD, reduce bypass pumping to the Ecorse Creek and limit the future risk of basement flooding by providing storage during wet weather events and eliminating hydraulic bottlenecks in the sanitary sewer system.

Jan 1, 2013

By Robert Stefanko

The concept of disposing of liquid industrial wastes by deep-well injection is not a new one. Brines associated with crude oil long have been disposed of in this manner, with the additional benefit of aiding secondary oil recovery. More recently, with the expansion of nuclear energy, the lethal, highly radioactive wastes which are by-products of the fission process have created severe disposal problems. During the past ten years, a variety of industries have resorted to subsurface disposal, some of the details of which are given elsewhere (1,2). The list reveals wide variations in injection rate, pumping pressure, cost, and waste disposition. Included are successful installations in Western Pennsylvania.

Jan 1, 1969

By Lawrence M. Zanko

Eighteen coarse taconite tailings samples were collected in 2000-2001 from five western Mesabi Range taconite (iron ore) operations located in northern Minnesota, i.e., EVTAC, Hibbing Taconite (Hibtac), USX Minntac, Ispat Inland (Minorca), and National Steel Pellet Company (NSPC), to test their physical, geological, chemical, and mineralogical properties [Zanko, L.M., Niles, H.B., Oreskovich, J.A., 2003. Properties and aggregate potential of coarse taconite tailings from five Minnesota taconite operations, Minnesota Department of Transportation, Local Road Research Board, St. Paul, MN, Report No. 2004-06 (also as Natural Resources Research Institute technical report, NRRI/TR-2003/44)]. The goal was to assemble a body of technical data that could be used to better assess the potential of using a crushed taconite mining byproduct like coarse tailings for more widespread construction aggregate purposes, primarily in roads and high¬ways. An important part of the mineralogical assessment included X-ray diffraction (XRD) analyses and microscopic (polarized light microscopy, scanning electron microscopy, and transmission electron microscopy, i.e., PLM, SEM, and TEM, respectively) evaluation of the size and shape (morphological) characteristics of potentially respirable microscopic mineral particles and fragments. Quantitative mineralogy, based on XRD analyses, showed that the dominant mineral in all samples was quartz (55-60%), followed by much smaller amounts of iron oxides, carbonates, and silicates. Specialized microscopic analyses and testing performed by the RJ Lee Group, Monroeville, PA, on both pulverized (-200 mesh, or 0.075 mm) and as-is sample composites showed that no regulated asbestos minerals or amphibole minerals were detected in the western Mesabi Range samples. A small number (26) of non-asbestos and non¬amphibole mineral cleavage fragments/mineral fibers were detected by SEM out of 1000 fields analyzed, but most were identified as min¬nesotaite and talc, silicate minerals common to the Biwabik Iron Formation. Amphibole minerals, absent in coarse tailings samples from the five western Mesabi Range taconite operations, were present in a single eastern Biwabik Iron Formation sample collected in 2003 for Lake County from the Cliffs Northshore operation in Silver Bay, MN. Importantly, the Superfund Method for the Determination of Releasable Asbestos in Soils and Bulk Materials [United States Environ¬mental Protection Agency (USEPA), 1997. Superfund method for the determination of releasable asbestos in soils and bulk materials, EPA 540-R-97-028, U.S. Environmental Protection Agency, Washington], as modified by Berman and Kolk [Berman, D.W., Kolk, A.J., 2000. Modified elutriator method for the determination of asbestos in soils and bulk materials, Revision 1: Submitted to the U.S. Envi¬ronmental Protection Agency, Region 8, May 23, 2000] failed to generate any protocol fibers, i.e., fibers longer than 5 µm and thinner than 0.5 µm, from either the western coarse tailings samples or the single eastern Biwabik Iron Formation sample. The combined findings suggest coarse tailings and other taconite mining byproducts should be treated with the same common sense safety and industrial hygiene approach practiced for all mineral-based materials that have the potential to generate respirable dust. © 2007 Elsevier Inc. All rights reserved.

Jan 1, 2007

By I. Ocak

Initial investment for mechanical boring of tunnels is found to be high in most cases. Conventional drilling and blasting is not the possible especially in urban area. In these conditions impact hammer offers many advantages over conventional drill and blast techniques and boring tunnels. These include improved safety, minimal ground disturbances, elimination of blast vibration, reduced ventilation requirements, reduced cost etc. Therefore, hydraulic impact hammers have been used widely in metro tunnelling projects in Istanbul since 1992. Accumulated and published data from various tunnelling projects serve to improve predicting the machine performance and scheduling of job duration. This paper is prepared under this objective. Machine utilization time of impact hammer was evaluated in this study. The main rock formation named Kartal formation arepaleozoic aged sedimentary rocks, shale, sandstone, siltstone, andesite dykes and sediment fillings. The first stage of the project is commissioned to Yapi Merkezi- Yuksel- Dogus- Yenigun- Belen consortium.

Jan 1, 2011

By W. G. Pariseau

Joints may be taken into account when using numerical modeling as an aid to mine design by embedding joints in the model. When using the popular finite element method, say UT3PC, a pre-analysis step is necessary, Step 0. This step is for the computation of equivalent properties of a representative elementary volume of jointed rock (REV) in the model. This Step 0 is taken before Steps 1, 2 and 3 for specification of a rock properties file, generation of the mesh, and model analysis are taken. A brief explanation of equivalent properties and several examples aid in explaining the details of Step 0. Focus is on procedures, input files, and output to show ease of computation. Theoretical details are relegated to references (e.g. Pariseau 2022). Comparisons of safety factor distributions about example mine excavations with direct scaling from mine observations then offer some insights concerning equivalent properties, especially strengths.

Feb 1, 2023

By Lawrence Williamson, Randall J. Essex, David P. Field

As part of a $2.2 Billion bridge project that will link Indiana and Kentucky, an interchange project northeast of Louisville will require the mining of a 6-lane tunnel system about 2,000 ft long in order to cross beneath the historic Drumanard Estate. This paper will discuss preliminary engineering that has been undertaken to compare two-bore and three-bore layouts, the planning of an exploratory tunnel facility, and the potential for including a test chamber to investigate the ability of high capacity roadheaders to mine the 22,000 psi limestones.

Jan 1, 2005

By V. K. Kollipara

Air flow patterns in the face area of a room-and-pillar mining are critical for understanding the dust dispersion characteristics and for developing engineering controls. SIUC has previously performed a CFD study to analyze the airflow patterns in the face area when continuous miner is making a straight cut. Results from this study identified low air velocity and re-circulation zones in the face area and illustrated the significance of line curtain, and scrubber operation on the air flow patterns. This paper discusses similar analyses when continuous miner is making a right turn cut as it is considered to be the dustiest cut among all the cuts made to advance an entry through a crosscut. This paper presents results for box-cut development for a right hand turn x-cut. This paper also addresses line curtain advance and air leakage through the curtain on the airflow patterns in the face area for such a cut. Low air velocity and recirculation zones were identified by analyzing the velocity vectors.

Jan 1, 2012

By MUSTAFA ERKAYAOGLU, ENVER YILMAZ

Coal is still a part of energy generation worldwide and has a significant role in the sustainable development of countries. The amount of shallow coal deposits is getting scarce, making efficient underground mining operations crucial for both local and global economies. In underground mining operations, longwall mining is a commonly utilized method to extract deep coal deposits. One of the leading engineering goals in longwall mining is increasing the efficiency of the system by investigating the effects of operational factors on equipment. This paper investigates the shearer performance for a longwall top coal caving operation by discrete event simulation that includes modeling the double-drum shearer, belt conveyors, stage loader, and armored face conveyors (AFC) to evaluate system performance by considering the amount of daily coal production of the shearer. As a result, the most influential factor on mine production is determined and a data-based framework is developed. This study suggests a framework for data collection, data analysis, and the interpretation of the operational data to evaluate the primary production unit’s performance. The models developed for the face coal extraction operations in a longwall top coal caving (LTCC) mine have a bi-directional cutting system and can be implemented in other operations readily.

Jul 2, 2021