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By G. Wozniak, R. Rostanski, H. Pfanz, G. Aschan, E. Sierka

"Industrial wasteland is a typical element of the landscape of all the industrialised regions in Europe. There are many examples from Poland as well as from other European countries that post-industrial sites have been undergone natural colonisation and succession to establish in some cases ecosystems of greater biological diversity than the original ecosystems. The post-industry sites regardless of any reclamation carried out, undergo natural successional processes. The respective biological diversity (number of species, and number of plant assemblages) reflects the micro-variety of the specific habitat. This paper summarizes the results of investigations, which have been carried out since 1989 on coal mine water sedimentation pools in the Upper Silesia Industry Region. The aim of this study is to demonstrate the diversity of spontaneous plant communities recorded on post-industrial waste sites. In the course of the long time fieldwork, plant assemblages representing nine phytosociological groups have been identified."

Jan 1, 2005

Designing for early access to deep orebodies is an essential driver for improved project payback. Vertical shaft sinking techniques have been developed to allow concurrent mine level excavation while continuing to sink. Project cash flows can also be improved when simultaneously deepening existing shafts beneath operating hoisting systems. Further economic advantage has been realised through creative sinking sequencing in twin ventilation/service shaft projects. A fourth technique to reduce project schedules involves partial shaft barrel equipping allowing unrestricted access to construct stations and continue with level installations. This approach reduces interference with barrel sinking activities to insignificant proportions. This paper reviews how these approaches have added significant value to actual shaft sinking projects, as assessed from a contractorÆs perspective, and discusses some of the practical issues to be addressed when planning future projects. Designers need to take cognisance throughout all project engineering phases of the adage that you are only sinking when cleaning the face. Cleaning can only be sustained when there is sufficient hoisting capacity.

Jan 1, 2005

By A. M. Galperin

Back analysis is a very important procedure for proper understanding of physical processes. Back analysis can be used to establish the role of different factors, define parameters to be calculated and formulate the behavior of natural or physical processes based on field experimental results. It is evident that, in order to obtain the necessary data for back analysis, field observations are required. For the Michailovsky region (Kursk Magnetic Anomaly, KMA) the long-term strength characteristics of the clay covering the quarry slopes were established with the help of back landslide calculations. The obtained data allowed quantification of the shearing resistance parameters at the presence or absence of intermittent dips of discharge in the pit bank massif structures. Based on the results of investigation for material composition, strength and deformation of finely dispersed (clay-chalk) deposits in the Kursk Magnetic Anomaly including measuring of the settlements of filled structures, complex probing and laboratory determination of water-physical and mechanical properties of "man-made" soils, engineering-geological zoning of filled structures was carried out.

Jan 1, 2005

By Kenneth N. Han, Peter Nam-soo Kim

A kinetic model for leaching of particulate metals in a batch system has been developed. The leaching mechanism has been analyzed by solving a series of ordinary differential equations relating heterogeneous reaction kinetics at the solid/liquid interface to mass transfer of reactant and products. Special emphasis has been given to the effect of changing of the surface area of the leaching substrate and initial particle distribution on the overall leaching rate. The dissolution of gold powders in acidic solution with bromine as an oxidant has been used as a model system. The effect of particle size, chemical reaction order, rate constant and mass transfer coefficient on the overall rate of dissolution of metal powder has been analyzed and discussed.

Jan 1, 2005

By K Ellis, B Lumsden

A full-scale statistically-based on/off plant trial of a new flotation conditioning technology designed to improve fine mineral recovery was undertaken to determine whether the recovery of selected fine sulfide minerals can be increased. The technology is selective for certain sulfide minerals only, including chalcopyrite and sphalerite. The technology has been shown to selectively aggregate the fine chalcopyrite and sphalerite minerals giving increased flotation recovery. The plant trials have shown an increase in the mineral recovery, without decreasing selectivity. Size by size recovery shows a significant increase in the fine (

Jan 1, 2005

By Christophe Thiébaut

Keywords: Pyrochemistry, Salts Treatment, Distillation The pyrochemical purification of metal generates spent salts. When this metal is an actinide such as plutonium, the slags cannot be discarded and are thus disposed in nuclear facility. In order to handle with these slags, the decision has been taken to reduce stored quantities. The development of a pyrochemical treatment is in progress in the CEA Valduc centre. The feed salt, typically composed of various Pu and Am species contained into monovalent or divalent chloride matrix, is first oxidized to convert the actinides into oxides. Then the chlorides are separated from the actinide oxides by vacuum distillation. Temperatures higher than 750°C for monochloride salts mixture NaCl/KCl and higher than 1100°C for divalent CaCl2 base salts, are required to produce an industrial flow of vaporization. Inactive qualification of the process for NaCl/KCl base salt has been carried out with lanthanide surrogates. Then, a pilot equipment, called distillator has been designed and built for production-scale distillation of NaCl/KCl and CaCl2 oxidized plutonium salts. Industrial flows of vaporization have been obtained with this pilot equipment : about 4 g/cm²/h for NaCl/KCl at 800?900°C and 1 Pa, and more than 1,5 g/cm²/h for CaCl2 base salts between 1000?1200°C at 0.1 Pa. The last step, now in progress, is the integration of the distillator into a glove box.

Jan 1, 2005

By Karim El-Ouassiti, Marc Minville, Stéphane Chabot, Claude Bazin, Valérie Ouellet

"Alumina is the main source of aluminium and it is extracted almost exclusively from bauxite ores found in the Southern hemisphere. Clays are abundant minerals that contain from 15 to 40% w/w of alumina from which it can be extracted by various processes. This paper reviews the processes used for the extraction of alumina from clays and discusses results obtained with a clay sample from the Murdochville area in the Quebec Province. The application of a conventional process to this clay did not yield an acceptable recovery although smelter grade alumina was produced. A modification to the process allows increasing alumina recovery from 85% to more than 92%. The application of the improved flow sheet to other alumina carriers failed to yield comparable recovery, showing that an optimum processing path for the recovery of alumina should be found for individual clay materials.INTRODUCTIONMost of the aluminium smelters are fed with alumina extracted from bauxite found in the Southern hemisphere. Bauxite is processed by the Bayer process that uses a caustic leach of the ore. In the middle of the century, the US Bureau of mines, motivated by the fear of an alumina delivery disruption, conducted several research projects aiming at producing alumina from non bauxitic ores. These projects led to the development of various acid leaching processes (Habashi, 1993). The sulphuric and hydrochloric acid leaching processes were brought to pilot plant evaluation (Bengtson, 1979), while nitric and other leach liquors were tested in the laboratory (Phillips and Wills, 1982; Habashi, 1983). Although clays are abundant and inexpensive minerals, the studied processes remained uncompetitive with the alumina extraction from bauxite (Hudson, 1987 page 42; Peters et al., 1962) for which reserves are estimated to support alumina production for the next 50 years (Oye et al., 1999). On the other hand, the local extraction of alumina from clays could significantly reduce the transportation costs of alumina to smelters and provide an alternative source of alumina supply from the Southern hemisphere countries. Also, the extraction of secondary products for some types of clay (Nasyrov et al., 1999) containing significant amounts of potassium and sodium could provide an additional return that may improve the economics of alumina production from clays."

Jan 1, 2005

By Christopher J. Oates

Overview ? Mining Codes ? Best Practice ? Mining Standards Guidelines ? Get it right from the start ? External Auditors ? The 5% rule ? MMCRM's - The Key Components ? The MMCRM Report / Certificate ? MMCRM's & Round Robins ? Summary

Jan 1, 2005

Heatings, fires and explosions in New South Wales (NSW) and Queensland coal mines since 1972, are reviewed. Geological and mine settings are outlined. Where available, gas analysis and critical decisions are discussed. This paper updates work by NSW Department of Mineral Resources (1995) and the Queensland Department of Mines and Energy in a report on fires and explosion in Queensland coal mines (Richardson and Ham, 1996). Incident data has important applications in terms of evidence-based risk assessment and identifying key issues to be integrated into competency based training programs. Predictive indicators are reviewed in terms of coal parameters in seams where the incidents occurred.

Jan 1, 2005

CSIRO Minerals, in association with the AJ Parker CRC for Hydrometallurgy, has an active program of hydrometallurgical research in which physical and computational modelling are used to better understand and improve a range of different unit operations. The modelling is based on flow simulation (Computational Fluid Dynamics or CFD), but incorporates other physical and chemical phenomena of importance, such as droplet break-up and coalescence, species transport and reaction. This paper reviews some of the major projects that have been undertaken at CSIRO Minerals and will illustrate the critical importance of hydrodynamics to the performance of unit operations and the improvements that can be made to performance using such modelling techniques. Unit operations that are discussed include solvent-extraction, gravity thickeners, flotation cells, bio-heap leaching and stirred tanks.

Jan 1, 2005

By Steve Kral

The coal mining industry in the western United States is seeing the same boom as the rest of the country and the world. Most coal mines in the West are operating flat out as the nation’s appetite for energy continues to grow. And many of the coal mines have either increased their production capacities or are in the process of doing so. However, transportation issues along with environmental restrictions are keeping many mines from expanding even further. Some coal companies held off on further expansion plans until Congress and President Bush could agree on a national energy policy, one that recognizes coal as the nation’s leading source of electricity. In August, Congress passed and the president signed into law such a measure (see Washington Survey, page 7). The legislation includes research funding for clean coal technologies. So western and eastern coal could become even more important in the national energy picture. This is particularly true as supplies of natural gas diminish and the price of oil continues to increase.

Jan 1, 2005

By Chen Song

Keywords: Mixed extractant, Copper, Cobalt, Nickel, Synergistic effect During separation process of copper and cobalt from nickel sulphate solution, the effects of constitutions and compositions of mixed extractant D2EHPA and PC88-A or Cyanex 272, has been studied. In one step extraction cycle, the following results are obtained:[Ni]/[Co]>4000 and [Ni]/[Cu]>40000 in nickel sulphate solution, [Co]/[Ni]>1000 and [Co]/[Cu]>30000 in cobalt chlorinate solution, [Cu]/[Ni]>10000 and [Cu]/[Co]>200 in copper sulphate solution. It was elucidated that the above-mentioned synergistic mixtures can effectively separate cobalt and copper from nickel sulphate acid solution and achieve a greater synergistic effect.

Jan 1, 2005

The ~2500 km long Kermadec-Tonga arc northeast ofNew Zealand is the longest continuous intraoceanic arc in the world. At least 94 volcanic centres along the arc are submarine, most (87 per cent) within the Kermadec arc (de Ronde et al, 2003a). Volcanic rocks range from basalt to rhyodacite with trace element and isotopic data indicating significant magma source heterogeneity both along and across the arc.   The entire ~1300 km of the Kermadec arc has now been surveyed for hydrothermal emissions (de Ronde et al, 2004). First-stage surveys utilised surface vessels. In February 1996, the first sulfide samples from the southern Kermadec arc were dredged from the Brothers and Rumble II West caldera volcanoes (R/V Tangaroa cruise TAN96/03; Wright et al, 1998; de Ronde et al, 2003b). In September 1998, low-temperature, diffuse venting was discovered at Monowai, Rumble III and Clark volcanoes, and high-temperature, black smoker venting was found within Brothers caldera (R/V Sonne cruise SO-135; Stoffers et al, 1999). The NZAPLUME cruise of March 1999 surveyed 13 volcanic centres (each mainly comprised of single, large volcanoes) of the southern Kermadec arc and documented hydrothermal emissions above seven of them (de Ronde et al, 2001; Baker et al, 2003; Massoth et al, 2003). In July 2001, additional mineralised and hydrothermally altered samples were dredged from Brothers volcano (R/V Tangaroa cruise TAN01/07). The NZAPLUME II cruise of May 2002 confirmed venting was still occurring at all the known hydrothermal sites, and that ten active vent sites occurred along the mid-part of the arc, between Brothers and Raoul Island (de Ronde et al, 2002). In September-October 2004, NZAPLUME III surveyed the northern-most part of the Kermadec arc where another nine volcanic centres are hydrothermally active.   Second-stage exploration of the Kermadec arc hydrothermal systems utilised deep submergence vehicles. In October-November 2004, the Japanese submersible Shinkai 6500 made four dives on Brothers. Samples recovered include vent fluids, chimneys, altered rocks and various animals and microbes. In April-May 2005, a more extensive expedition using the American submersible Pisces V made 23 dives on nine different volcanic centres, eight of them for the first time.   Extensive plume surveys show Brothers volcano is host to the most hydrothermally active sites of all those known along the Kermadec arc. In total, nine dives have been made on Brothers, six on the NW caldera site and three on the cone site. The NW caldera vent site is a long-term hydrothermal system that is today dominated by evolved seawater but has had episodic injections of magmatic fluid. The cone site is a nascent magmatic-hydrothermal system where crack zones localise upwelling acidic waters (de Ronde et al, 2005). A SE caldera site represents the main upflow of a relatively well-established magmatic-hydrothermal system on the seafloor where sulfide-rich chimneys are extant. Each of these different vent sites represent diverse parts of an evolving hydrothermal system, any one of which may be typical of submarine volcanic arcs.

Jan 1, 2005

By J Cahill, D Holden, R Stuart, G Cryan, W Power, W Stratford, S Garwin

The combination of Stage 1 Geoinformatics legacy data intervention processes with the Stage 2 ultra-detailed airborne geophysical prospecting demonstrates a new approach to converting data to information to knowledge, and converting that knowledge into exploration results.   The Coromandel region of the North Island of New Zealand has long been know to host gold deposits of economic viability (Hauraki Gold Fields). To the SE of this area lies the Taupo Volcanic Region (TVR) where the geology and structural setting mirror the Hauraki Gold Fields, however mineral exploration in the past has been hindered by the blanketing volcanic ash deposits. Glass Earth Limited recognised that this whole potential epithermal gold province could be effectively explored utilising rapid, risk orientated processing to review legacy geoscience data: The Geoinformatics Data Intervention Process; which in turn directed ultra detailed airborne geophysical surveys over the TVR. Results have outlined 21 new drillable potential epithermal gold targets; and a plethora of other targets with high prospectivity.

Jan 1, 2005

By C Agreda

The Cushion Blasting Technique applied to solve the high risk case history represented by a 10,704 TM rock locate at 120 M from the hydroelectrical plants of 350 KV each, is described, analyzed and discussed. The generation and distribution of 700 KV produced by two hydroelectrical plants must not be interrupted by any reason, because the 26 district of the province of cajatambo, of the Lima department; would not have electrical power. The search of the best alternative and methodology, the drilling and blasting pattern calculations, charge design and loading, connections and initiations of the 50 blasts are described, analyzed and discussed. Finally, the excellent results from a technical, economical, enviromental and safety point of view of the 50 primary blasts are discussed and emphasized.

Jan 1, 2005

By J. Jankovic

Numerous advantages have been recognized for solid oxide fuel cells (SOFCs) operating at temperatures of 500-700°C. However, there are several issues related to low temperature SOFCs, such as high electrolyte resistance and high electrode polarization. One of the routes to enhance the electrode performance, particularly for the cathode, is to use new materials with optimized microstructure. In this work, the plasma-spraying technique, recognized to have several advantages over presently used deposition techniques, was used to deposit cathode materials onto ceramic and stainless steel substrates to obtain highly porous structures. Cathode materials with composition of Lao 6Sr0.4Co02Fe0 8O3 (LSCF) were employed in the powder form. The LSCF was prepared from powder precursors with different pore formers and binder levels, or from already produced, single-phase LSCF. The (La0.8Sr0.2)0.98MnO3 (LSM) cathode material was also processed for comparison purposes. The deposition process was developed to obtain coatings with good bond strength, porosity, film thickness and residual stresses. The phase and microstructure of deposited materials were characterized using XRD and SEM.

Jan 1, 2005

By C. A. Pickles

Microwaves are being applied industrially in a number of fields and possess a number of potential advantages that could be applied in extractive metallurgy. Microwave heating has a number of unique characteristics, which distinguish it from the conventional heating methods. In microwave heating, the absorption of energy occurs at the molecular or atomic level and therefore the heat is generated within the material itself. In conventional heating, the exterior temperature is usually higher than the interior, but with microwave heating, the temperature gradient is inverted and thus the interior temperature can be much higher than that of the surface. The energy densities in microwave systems can be relatively high and this in combination with the low thermal conductivities of oxide ores, can lead to very high internal heating rates. In this research, the application of microwave energy for the reduction of a nickeliferous silicate laterite ore has been investigated. The real and imaginary permittivities are the two fundamental properties which determine the microwave absorption characteristics of a material and these were measured for the ore, both with and without carbon additions using the cavity perturbation technique. The microwave heating and reduction experiments were performed in a 0 to 2 kW CTC microwave system. The effects of power input, processing time, sample mass and charcoal additions on the microwave absorption were investigated. Then reduction experiments were performed and the nickel grade of the magnetic concentrate and the nickel recovery in the concentrate were determined.

Jan 1, 2005

By Sunil S. Basarkar, Dilip M. Dewaikar, Rajesh H. Gajjar

"A load transfer program AXPILE was developed for simulation of the loadmovement characteristics of socketed piles of the Mumbai reg ion. This program used empirical relationships for ultimate shaft resistance at pile-rock interface recommended by Zhang and Einstein (1998). According to their recommendation, ultimate shaft resistance at pile-rock interface is related to the square-root of uniaxial compressive strength of intact socket material by a parameter C, which ranges from 0.4 for smooth sockets to 0.8 for rough sockets. Results of three instrumented pile load tests were compared with the AXPILE generated results. The comparison of analytical and field estimates of the unit shaft resistance confirm the recommendations of Zhang and Einstein (1998) on the unit side shear parameter c,, which was found to be in the range of 0.35 to 0.67.INTRODUCTIONInstrumented pile load tests were carried out on the test piles at the Bandra-Worli sea link project in Mumbai city of western India. High capacity socketed piles were required to take up loads from the superstructure. Hence, in addition to the available toe resistance, an accurate measurement of the shaft resistance in socket portion was desired. The instrumented load tests incorporated Osterbergcell (0-cell) assisted by strain gauge instrumentation to estimate the shaft resistance mobilization in the socket portion.AXPILE load transfer program was developed for load-movement simulation of socketed piles (Basarkar, 2004). The load transfer algorithm based on Coyle and Reese (1966) was incorporated in this program, which used empirical correlations and functions to account for load transfer in piles through shaft and toe resistance.This paper compares the computed unit shaft resistance from the AXPILE program with the measured values recorded from the instrumented pile load test."

Jan 1, 2005

By P Carrasco, E Me, M Campos, J Tapia

Correct sampling practices are of vital importance to the mining industry; key decisions for the business are made on the basis of samples in all the value chain. Geology plays a relevant role in pre- and post-investment stages. Actually the understanding of natural variability is essential for geological modelling, geometallurgical modelling, mine planning, grade and process control. Improper sampling practices obstruct this objective introducing irrelevant variability components, which can cause monumental economic losses. A good approach to accomplish this understanding is the application of heterogeneity and IngamellsÆs tests, which are useful tools to quantify the variability of a certain well-delimited geological unit at different comminution scales. The application of heterogeneity test can help minimise Pierre GyÆs fundamental sampling error and to study the impact of other sampling errors. IngamellÆs test allows us to define the correct mass of sample for chemical analysis. This paper presents the results of several heterogeneity and IngamellsÆs tests done in Chilean porphyry copper deposits that belong to CODELCO Chile (Chuquicamata, Mina Sur, Radomiro Tomic, El Salvador, Andina and Teniente), in different geological units (endogenous oxides, exotic oxides, supergene sulfides and hypogene sulfides) and for several elements (Cut, Cus, Mo and As). These tests, considering the natural variability, have helped us develop accurate sampling protocols to minimise the fundamental error to acceptable levels. A major contribution of these tests (more than 30) is the generation of secure sampling protocols using the highest sampling constant obtained in the tests, for new porphyry copper deposits that donÆt have information given by heterogeneity and IngamellsÆs tests.

Jan 1, 2005

By H. Jung

The microstructures and grain sizes of nanocrystalline Co and Co-1.1 wt % P alloys were characterized by X-ray diffraction. The corrosion properties of as-deposited and annealed Co-l.l wt % P alloys and pure nanocrystalline Co were studied in a deaerated 0.1M H2SO4 solution using electrochemical measurements and XPS surface analysis. Potentiodynamic polarization testing and impedance measurements revealed that an addition of P to pure nanocrystalline Co improved the anodic-corrosion resistance, however, this enhanced corrosion resistance was compromised by the heat treatment process at 350 and 800°C. The corroded surface of annealed nanocrystalline Co-1.1 wt % P at 350°C exhibited a more porous P-enriched layer compared with the as-deposited case. A sample annealed at 800°C corroded uniformly showing second-phase precipitates. The enhanced corrosion resistance of as-deposited nanocrystalline Co-1.1 wt % P was attributed to the elemental P on the surface that acted to hinder the anodic dissolution kinetics of surface Co following an initial selective dissolution of Co. However, at a higher anodic overpotential region, the superior corrosion resistance of Co-l.l wt% P alloys did not last because of the formation of a non-protective surface film consisting of mainly hypophosphite and phosphate as well as elemental P.

Jan 1, 2005