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By Hasan Nizamoğlu, Z. Abidin Sarı, Aslıhan Demiraslan, M. Deniz Turan, Tolga Depci

In this study, recovery of copper from solid material (obtained by leaching of chalcopyrite with oxalic acid in the presence of hydrogen peroxide) with a copper oxalate structure was carried out selectively using HCl. The chemical composition of the solid was as 29.3%, 9.7%, and 13.3% for Cu, Fe, and S, respectively. Selective recovery of copper by degrading the copper oxalate structure with a low-solubility product (Ksp = 4.43 × 10−10) was performed by conventional leaching in the presence of HCl. The optimum leaching conditions were determined as 5 M of HCl concentration, 318 K of leaching temperature, 120 min of leaching time, 25 ml/g of liquid–solid ratio and 400 rpm of stirring speed. Under these conditions, approximately 77% of copper and 3% of iron were taken into the solution. According to the characterization of the leach residue that was obtained, the oxalate structure was degraded. Moreover, the results of XRD analysis showed that the sulfur (S) and cubanite (CuFe2S3) phases were mostly observed in leaching residues, and this was supported by the SEM-EDX data. Based on the results, it may be stated that selective copper extraction can be obtained from a chalcopyrite concentrate by a two-step leaching method using a conventional hydrometallurgical technique.

Flow Sheet Development of Three Geographically Distinct Chromium-Bearing Ores

Sep 13, 2010

By P. C. -H. Rhee, H. -G. Lee, J. -H. Choi, D. S. Kim, S. -B. Lee

In order to predict the composition of inclusions and to ascertain a method to prevent inclusions from forming in liquid Fe-16 mass Cr alloy, a thermodynamic database was developed through a quantitative determination of thermodynamic relationships of Cr-Al-Si-Mn systems in the liquid Fe alloys. Applications of the databases to the prediction of Mn/Si complex deoxidation with Alin Fe-16 mass Cr alloy were demonstrated in succession. The electromagnetic levitation technique using a cold crucible was employed to separate inclusions from liquid metallic alloys completely and to prevent any contamination from surroundings. Various interaction parameters in the liquid Fe-16 mass per cent Cr alloy system were determined; these are: [eAl(Fe)Cr= 0.19/T, rAl(Fe)O,Cr= -0.01, rAl(Fe)O,Cr= -0.00013, eS1Cr(Fe)= -0.38/T,rSi(Fe)O,Cr= 0.007, rO(Fe)Si,Cr= 0.0044, rA1(Fe)Si,Cr= -0.0075, rSi(Fe)A1,Cr= -0.0078, rSi(Fe)Mn,Cr= 0.005, and rMn(Fe)Si,Cr=0.01.] An improved database, utilizing interaction parameters for molten metal determined in this study, and the Fact Sage slag database of the MnO-SiO2-Al2O3-CrOx-MgO system were used for thermodynamic calculations. These were carried out under various thermodynamic conditions, and results were compared with experimental data of Si/Al, Mn/Si, and Mn/Si/Al deoxidation equilibria. With the abovementioned results, together with experimentally obtained data, thermodynamic conditions were determined, in particular Mn and Si contents, under which liquid inclusions form in liquid Fe-16 mass per cent Cr alloy. The critical Al content in liquid Fe-16 per cent Cr alloy, above which solid inclusion of corundum phase ((Al,Cr)2O3) formed, was as low as 10 ppm. This indicates that extreme care must be taken in controlling the Al content in the metal to avoid formation of solid corundum phase ((Al,Cr)2O3) inclusion. The compositional change prediction of inclusions, which originate from slag entrapment and by Ca addition, was demonstrated by use of the alloy database optimized through this study, and the Fact Sage oxide database. For Si-deoxidized Fe-16 per cent Cr alloy, high Si and low basicity of slag are effective to obtain liquid inclusions. For Al-deoxidized Fe-16 per cent Cr alloy, it is important to keep the Si content lower than 0.1 per cent and it is required to add Ca. Keywords: inclusion, thermodynamic simulation, deoxidation, Fe-16 per cent Cr alloy,stainless steel, interaction parameter, cold crucible

Jan 1, 2004

By N Clarke, R Dineen, W Jones

The Mt Lyell copper mine in western Tasmania has discharged acid drainage (AD) into the Queen and King Rivers and Macquarie Harbour for over a century. Presently, dissolved copper loads of about 1000 tonnes per annum and dissolved aluminium loads of >2000 tonnes per annum are contained in the AD, which is derived from underground workings (~60 per cent) and historic waste rock dumps (~40 per cent). Flows vary from about 100 L/s during dry periods, to >400 L/s during the wet winter. The site is presently operated by Copper Mines of Tasmania (CMT) who are not responsible for the acid drainage generated from the mine site. Although western Tasmania is famous for its mining history, tourism and aquaculture have emerged as the new industries on the West Coast, with a major tourism railway (the Abt) recently opened along the banks of the Queen and King Rivers. The emergence of these industries in a æclean greenÆ Tasmania has resulted in a strong community and government push to remediate the acid drainage. Remediation investigations and efforts at Mt Lyell were initiated by the Department of Primary Industries, Water and Environment (DPIWE), previously known as DELM, in 1995, and have included the quantification of environmental impacts arising from the AD, and the investigation and costing of potential remediation options. A primary focus of the work has been to identify cost-neutral options which recover metals from the AD in a saleable form to help defray on going treatment costs. This paper summarises these activities in generally a chronological order, highlighting findings of the program that are potentially applicable to other acid drainage sites.

Jan 1, 2003

By Lewis Blanchard Brown

It is my purpose in the following paper to describe the south-central part of Siberia, with special reference to its geology and the mineral deposits. This region is known politically as the Achinsk and Marinsk districts of the Tomsk Government. It is situated among the Altai mountains, in. ]at. 50° to 55O n and long. 87O to 93O E., not far from the northern frontier of Mongolia, and is divided as follows: Mining Districts.—(1) The Tomsk mining district, including the political districts of Altai (belonging to the private crown lands of the Russian Emperor) and Marinsk; (2) the AchinskMinusinsk mining district, including the political districts of Achinsk and Minusinsk; and (3) the North Yenisei mining district, situated in the northern part of the Yenisei political district of the Yenisei Government. Fig. 1 is a map of the Tomsk mining provinces, showing the useful mineral-deposits, excepting those of gold, and giving the routes of the railroads and post-roads connecting the various districts. Political Divisions.—The Tomsk Government is sub-divided into seven " oojesdy " or districts, as follows: Barnaul; Biisk; Kuznetsk; Kainsk; Kolyvan; Marinsk; Narim; and the Altai district (private land, as above). The Yenisei Government is sub-divided into five "oojesdy" or districts, as follows : Erasnojarsk ; Kansk; Yenisei; Achinsk; Minusinsk. Concerning the geology of the region, in addition to the record of my own observations, references will be made to the works of earlier writers. These have been consulted for the purpose of comparison, as regards the districts which I have actually traversed, and for the purpose of completing my account of such portions as I have not been able to visit.

Jan 1, 1904

By Robin B. Dill, Mark Pelletier, Daniel J. Dobbels, Subodh Bhaumik, Daniel J. VanRoosendaal

Although primarily cut-and-cover excavations are required for replacement of the existing elevated I-93 interstate highway through the heart of Boston for the Central Artery/Tunnel (CA/T) project, some mined tunnel construction was also undertaken. The mined tunneling conducted was the 22-m-wide northbound roadway structure which passed below a 20-m-deep operating underground subway station that was built in 1913. The innovative underpinning scheme used to support the subway station during construction resulted in the successful mining beneath the subway station with negligible vertical settlement. Two grouting galleries were carefully mined below the subway structure, and pre-grouting of the granulary, pervious glacial soils and weathered bedrock was carried out from these galleries. The reinforced concrete walls of the underpinning structure were constructed within three stacked drifts that were sequentially mined below each grouting gallery. After 11 cross adits were mined between the grouting galleries, cast-in-place post-tensioned girders that spanned between the stacked-drift walls were constructed to support the subway station. The stacked-drift walls also provided lateral support for the 22-m wide by 29-m long by13-m high opening beneath the girders.

Jan 1, 2001

By Gibbs R

The objective of this paper is to provide a broad qualitative perspective of the needs and costs of infrastructure associated with typical mining projects. Infrastructure may be defined as anything necessary for the development and operation of a project, which is peripheral to the basic extraction, handling and processing of material. As depicted in Figure 1, infrastructure acts as the link between the technological heart of a project and the outside world.

Jan 1, 1990

By Geoffrey Berry

Exposure?response relationships between the relative risk of lung cancer and quantitative measures of exposure to asbestos are available from a number of epidemiological studies. Meta-analyses of these relationships have been published by Lash et al. (1997) [Lash, T.L., Crouch, E.A.C., Green, L.C., 1997. A meta-analysis of the relation between cumulative exposure to asbestos and relative risk of lung cancer. Occup. Environ. Med. 54, 254?263] and Hodgson and Darnton (2000) [Hodgson, J.T., Darnton, A., 2000. The quantitative risks of mesothelioma and lung cancer in relation to asbestos exposure. Ann. Occup. Hyg. 44, 565?601]. In this paper, the risks derived in these meta-analyses have been compared. Lash et al., concentrated on process and found that the risk of lung cancer increased as the asbestos is refined by processing. Hodgson and Darnton concentrated on fibre type and found that the risk was highest for exposure to amphibole asbestos (crocidolite and amosite), lowest for chrysotile and intermediate for mixed exposure. Some of the differences between the conclusions from the two meta-analyses are a consequence of the choice of studies included. The range of asbestos types included in the studies in the analysis of Hodgson and Darnton was wider than that in Lash et al., enabling differences between fibre types to be analyzed more readily. There are situations where occupational exposure to chrysotile asbestos has shown no detectable increase in risk of lung cancer. Taconite miners have shown no increased risk of mortality due to lung cancer. © 2007 Elsevier Inc. All rights reserved. Keywords: Mesothelioma; Amosite; Grunerite; Taconite; Crocidolite; Tremolite; Anthophyllite; Winchite; Risk assessment; Etiology

Jan 1, 2007

By M Scoble

This paper will report on the application of data collected through the performance monitoring of large diameter surface rotary blasthole drii and electric mining shovels, in an integrated approach to blast optimizatiion.

Jan 1, 1992

By Mark Van Dyke, Ted Klemetti, Joe Wickline

"The identification and mitigation of adverse geologic conditions are critical to the safety and productivity of underground coal mining operations. To anticipate and mitigate adverse geologic conditions, a formal method to evaluate geotechnical factors must be established. Each mine is unique and has its own separate approach for defining what an adverse geological condition consists of. The collection of geologic data is a first critical step to creating a geological database to map these hazards efficiently and effectively. Many considerations must be taken into account, such as lithology of immediate roof and floor strata, seam height, gas and oil wells, faults, depressions in the mine floor (water) and increases in floor elevation (gas), overburden, streams and horizontal stress directions, amongst many other factors.Once geologic data is collected, it can be refined and integrated into a database that can be used to develop maps showing the trend, orientation, and extent of the adverse geological conditions. This information, delivered in a timely manner, allows mining personnel to be proactive in mine planning and support implementations, ultimately reducing the impacts of these features. This paper covers geologic exploratory methods, data organization, and the value of collecting and interpreting geologic information in coal mines to enhance safety and production.The implementation of the methods described above have been proven effective in predicting and mitigating adverse geologic conditions in underground coal mining. Consistent re-evaluation of data collection methods, geologic interpretations, mapping procedures, and communication techniques ensures continuous improvement in the accuracy of predictions and mitigation of adverse geologic conditions. Providing a concise record of the work previously done to track geologic conditions at a mine will allow for the smoothest transition during employee turnover and transitions. With refinements and standardization of data collection methods, such as those described in this paper, along with improvement in technology, the evaluation of adverse geologic conditions will evolve and continue to improve the safety and productivity of underground coal mining."

Jan 1, 2019

The Wainui Mill was conceived as a 60 - 90 t/d central mill to process gold ores of the Thames area of New Zealand from small mines in the district. The ores of the region exhibit various degrees of refractory response to conventional cyanidation leach due to the fineness of the gold, and association with pyrite. The alternative circuits involving cyanidation, flotation, and possible small-scale smelting are examined. The environmental impacts have been audited by the Commission for the Environment and were found to be acceptable.

Jan 1, 1986

By Luke Erickson

San Francisco Public Utilities Commission is planning to replace 5 miles of pipeline under San Francisco Bay. The tunnel will be constructed using an Earth Pressure Balance (EPB) TBM and will be the first TBM-driven tunnel under the Bay. The alignment passes under environmentally sensitive habitats, through interbedded layers of sands and clays, and through a buried bedrock ridge. This paper discusses the geotechnical characterization and anticipated tunneling conditions and presents the analysis of various construction methods that resulted in the selection of an EPB TBM. Considerations related to tunneling with an EPB TBM are described in detail, including ground conditioners, TBM cutterhead wear, muck control, and squeezing ground.

Jan 1, 2008

Efficacy of Enhanced Gravity Separator in Processing Indian Iron Ore Slime The slime sample was subjected to concentration using Falcon concentrator for their enrichment. The effects of three important variables, eg bowl rotation frequency, back water flow rate and per cent solid were studied on the process performance. Increasing the rotation of the Falcon bowl, enable more material to the underflow by increasing the yield, whereas, the iron content decreases steadily with increasing the rotation of the bowl. The increase in the back water flow effectively removes the clay materials from the underflow at the expense of the yield. Similarly, increasing the per cent solid concentration in the feed produces a better product both in terms of yield and Fe content. Results show that EGS/Falcon can be used for processing Indian iron ore slime and producing pellet grade concentrate.

Sep 13, 2010

By Clyde Sitterud

Presentation Agenda ?Global Mining Tire Demand ?What is driving it? ?Latest Situation ?How long it will last? ?Michelin?s Response to Increase Supply ?New plant ?Additional presses ?Recommendations for Mining Users ?Treat tires as your major assets ?Areas of attention that will produce immediate results

Jan 1, 2005

By Gerald C. Smith

Introduction Newmont Mining Corp.'s Carlin Gold Mining Co. mines gold ore and waste material from four open-pit mines in Northeastern Nevada. Combined production rate is 24.5 Mt/a (27 million stpy). The company is producing gold bullion from the 2.4 kt/d (2600 stpd) Carlin Mill No. 1. and the 2.3 kt/d (2600 stpd) Maggie Creek heap leaching plant. In August 1985, the 6.3 kt/d (7000 stpd) Carlin Mill No. 2 at Gold Quarry came on-line. The total combined throughput of 11.2 kt/d (12,000 stpd) will make Carlin Gold Mining one of the largest US gold producers. Feasibility studies are underway to increase the total gold out-put from Gold Quarry. This will be done by adding a continuous dump-leaching process that will recover gold from lower grade ore. History In 1961, Newmont exploration geologists located claims in the Lynn Creek mining district near Carlin, NV. An exploration drilling program revealed significant gold mineralization. A stepped-up drilling program revealed an ore body with an estimated 10 Mt (11 million st) of ore containing 109 t (3.5 million oz) of gold. Test results in 1963 allowed metallurgists to develop the flowsheet and design for a 1.8-kt/d (2000-stpd) countercurrent decantation (CCD) cyanide plant. Carlin Gold Mining Co. was formed to operate the property. Carlin purchased its first mining equipment in 1965. This consisted of two Bucyrus-Erie 2.7 m3 (3.5 cu yd) shovels and nine 27.2 t (30 st) Wabco Haulpak trucks, two Inger¬soll-Rand track-mounted drills, one Chicago Pneumatic T-650 rotary drill, one rubber tired Michigan 280 dozer, one Caterpillar D-8 36A track dozer, one Caterpillar 16 motor grader, and the necessary ancillary equipment. The fleet was capable of mining 3.2 Mt/a (3.5 mil¬lion stpy) working two eight-hour shifts, five days a week. In 1967, one P&H 1500 3.8 m3(5 cu yd) diesel electrical shovel and three 59 t (65 st) Dart trucks were added to the fleet, along with a Chicago Pneumatic rubber tire mounted rotary drill. This equipment addition increased the mining capabilities to 5.7 Mt/a (6.3 million stpy). Three separate pits, the Main, East, and West, within a 1.6-km (1-mile) radius of the Carlin mill were being mined. The crew consisted of 46 hourly men and three supervisors. This equals 497 t/ total hourly manshift (548 st) or 407 t/total manshift (515 st). Rising gold prices in the early 1970s allowed lower grade deposits to be mined at greater distances from the mill. The Boot-strap pit, 19.3 km (12 miles) north of Carlin, was started in 1973. Two Hough 45.4 t (50 st) front-end loaders, four Wabco Haulpak 45.4 t (50 st) trucks, and a second track type D-8H dozer were added. The higher grade ore was trucked to the Carlin mill using three

Jan 11, 1985

By Edna A. Dancy, Gerhard J. Derge

Jan 1, 1963

By Donald Thompson, Jessie Bonner, Ileana Tibuleac

Predicting ground motion from complicated mining explosions is important for mines developing blasting programs in regions where vibrations must be kept below certain levels. Additionally, predicting ground motion from explosions in complex 3D media is important for source size estimation for nuclear treaty monitoring. Both problems have been addressed under the development of a new series of programs including: 1) Generalized Fourier Methods to generate synthetic seismograms (Green’s functions) in 3D media for a moment tensor source implementation and 2) MineSeis3D, a program that simulates seismograms for delay-fired mining explosions with a linear relationship between signals from small size individual shots. To test the programs, three-component seismic recordings of three production shots at an iron mine in northern Minnesota were compared to synthetic waveforms in 3D media. Comparison of the observed and synthetic waveforms shows promising results. The shape and arrival times of the normalized synthetic and observed waveforms are similar for most of the stations. The synthetic and observed waveform amplitude fit is best for the vertical components in the mean 3D model but not as promising for the transversal components. The observed effect of spall on the waveform spectra was weak in the case of fragmentation delay-fired mining explosions. Commercial applications of the code could provide data needed for designing explosions that do not exceed ground vibration requirements posed by the United States Department of Interior, Office of Surface Mining.

Jan 1, 2005

By M. Tominaga

An industrial port complex was constructed on the west coast of Leyte Island The work was started in December 1981 and completed in May 1984. This port complex includes a 665 m long wharf and can accommodate vessels ranging from a 60,000 DWT ore carrier to a 4 000 DWT general cargo ship. It now handles materials for and products from a copper smelter with an annual capacity of 130,000 t and a fertilizer plant with an annual capacity of 900,000 t. The Wharf structures consist mainly of interlocked steel pipe piles, steel sheet piles and steel pipe Piles. Material handling equipment such as unloaders, shiploaders, etc. were installed on the wharf. Site survey, planning, engineering design and construction aspects of the port development are discussed in this paper with particular emphasis on the wharf structure.

Jan 1, 2010

Crocidolite deposits in the Hamersley Ranges, NW. of Western Australia, occur over a length of 180 miles and a width of 20' to 30 miles. Their stratigraphic environment and mineralogy is comparable to that of similar deposits of the Cape Belt, South Africa. It is probable that the known exposures' represent only a small portion of the total extent.Current production is wholly by Australian Blue Asbestos Pty. Ltd. at Wittenoom Gorge and has been in the order of 1,2,000 to 14,000 long t.p.a over the past six years.INTRODUCTIONThe Hamersley Ranges are located in the NW. Division of Western Australia and extend, approximately, from latitudes 21° 30' to 23°S and longitudes 117° to 1200 E. Their mean height above sea level is 2,000 ft, and they rise from 600 to 800 ft above the general level of the tableland which extends SE. from the coastal town of Roebourne.Mt. Bruce, the highest peak, is 4,024 ft above sea level. The ranges are intersected by numerous north-flowing streams, which are dry during the greater part of the year. These streams have carved deep gorges, and it is in these that the principal deposits of crocidolite outcrop.The presence of the mineral was first recorded in 1917, but the deposits remained untouched until 1937 when strong market demand for crocidolite resulted in considerable prospecting and mining activity, particularly in Yampire, Wittenoom and Dale's Gorges. It was established also that the blue asbestos belt extended from Willi Wolli Springs NW. to Millstream station, Le., over a length of 180 miles and a width of 20 to 30 miles. A number of attempts were made to develop and treat the Yampire and Wittenoom...

Jan 1, 1964

By Jeffrey C. Hillman

The need to recruit locally produced engineers by the South African Mining Industry led to the Engineering Faculty at the University of the Witwatersrand developing a number of academic bridging initiatives for educationally disadvantaged students. The graduation rate achieved during the initial five years of operation by the most successful of these programmes has been on a par with that of al other students but the performance of subsequent intakes has declined to such an extent that the continuance of this scheme could now be at risk. One reason for this reduction in throughput is that many of the applicants for the increasing number of mining bursaries have been more interested in the bursary than the profession and have either failed or dropped out due to a lack of application and motivation. This will have serious consequences for both Wits and the Industry if it continues and some method of identifying unsuitable or suspect applicants needs to be introduced as a mater of urgency. It is recommended that an introductory course be set up at a working mine that would be run under the auspices of Wits, as a joint venture with industry, and include a level of academic input that would provide both bridging needs and certain first year credits. The final form of this course will require extensive consultation with al parties but needs to be completed before the end of 1996. It is further recommended that the advertising and promotion of mining careers be expanded and much improved.

Jan 1, 1996