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By E. Ringdalen

Keywords: Pyrometallurgy, research, Norway, SINTEF, NTNU The Norwegian Ferro-alloy Industry and the model for research cooperation between SINTEF, NTNU, and the Norwegian ferro-alloy industry is presented as an introduction. The research within pyrometallurgy is illustrated by examples from characterisation of Mn-ores and characterisation of carbon materials. Examples from studies of reaction mechanisms in laboratory- and pilot-scale experiments are presented, in addition to an example of industrial off-gas measurements. Education possibilities at NTNU are also described.

Jan 1, 2011

By J. Baicker

A two-inch diameter probe containing an intrinsic germanium detector, a canister-type solid cryogen cooling system, cooled FET preamplifier, linear amplifier, high voltage supply, analog-digital converter, microprocessor, buffer memory, bidirectional cable link, and all power supplies has been designed, assembled and tested. A surface support vehicle was designed, built and outfitted. A mini-computer system was constructed and preliminary software developed and tested. A special handling system for a Cf-252 neutron source was designed and has been ordered. The entire system (less the neutron source) is ready for its first field tests. Lab description of the system is presented.

Jan 1, 1978

The oxidation of ferrous sulphate to ferric sulphate with air and oxygen in a gas lift percolator was investigated with initial Fe2+ concentrations in the range 0·01 M to 1·0 M,temperatures in the range 20-80°C, and pH in the range oto 2.The rate of formation of Fe3+ was found to be well described by the rate expressionEquation 1and a consistent mechanism is proposed.The presence of Cu2+ was found to cause an increased rate of oxidation, the effect being greater with Cu2+ concentrations increasing in the range 0·001 M - 0·01 M in 0·2 M Fe2+. The effect of other solutes containing Ni, Zn, Mn, Co, Hg, Cl, Mo, NH4, As, Cr, or Na at a concentration of 0·001 M in 0·2 M Fe2+ was negligible.

Jan 1, 1972

By M. Leroux, P. Lacombe, S. R. Rao, J. Y. Kim, J. A. Finch, G. Labonté, N. Macminn, M. Ounpuu

"Laboratory investigations on two complex ores, the A1 zone ore from Les Mines Selbaie and the Lyon Lake ore from Mattabi Mines Ltd. (Division of Noranda Minerals), have been carried out to determine some of the main variables in collectorless flotation. In particular, the effect of pulp potential (controlled by gas composition), conditioning time, pH and grinding media have been studied.Chalcopyrite showed the greatest response to collectorless flotation among the four major sulphide minerals present, followed by galena. Flotation of sphalerite was variable from minimal to important depending on the mineralogy and the pre-treatment performed. Appreciable silver recovery was achieved collectorlessly for the Lyon Lake ore while it could not be achieved for the A1 zone ore of Les Mines Selbaie. It appears that the difference between the two ores is related to silver's predominance as tetrahydrite in the Lyon Lake ore while it is as argentite and native silver in the A1 zone ore.The response of the ores to collectorless flotation is strongly dependent on the pulp potential, Ep, and pH. Using different gas compositions and different conditioning times it was found that collectorless flotation occurs when Ep is +195 to +295 mv (vs SHE). The actual on-set potential for collectorless flotation is dependent on the ore. A too high potential or prolonged oxidation leads to a decrease in selectivity. Some other factors were examined, notably the effect of pH and the type of grinding media on the selectivity achieved in the laboratory.Preliminary results from a plant trial at Mattabi Mines Ltd. confirmed that collectorless flotation occurs and that it is preferential for chalcopyrite and to a lesser extent galena. Collectorless flotation was not attempted at Les Mines Selbaie. However, examination of the distribution of collector between the different addition points in the copper circuit suggests that it may be present."

Jan 1, 1990

By N Coplin

Australian Coal Association Research Program (ACARP) project C25073 was proposed by industry stakeholders seeking a potential solution that improves underground air quality and reduces operational costs associated with technology used to control diesel particulate emissions in the underground coal mining environment.The need to protect workers from diesel particulate matter (DPM) has lead the underground coal mining industry to install disposable filter systems on their vehicles. While the disposable filters are efficient at removing significant amounts of DPM, the following major issues have arisen:- high cost of operations; disposable filters cost $A250–300 each and need to be changed at least once per shift resulting in an estimated cost of up to $A164 M/a, in filters alone, to the NSW underground coal mining industry- improper installation, damaged seals and lack of installing a new filter when the old filter is removed; workers are still being exposed to excessive amounts of DPM.The ACARP project successfully demonstrated significant DPM emissions reduction comparable to the incumbent disposable technology on a proof-of-concept wall-flow diesel particulate filter (DPF) system, as well as satisfactory system robustness when assessed using an industry representative test cycle representing operations of a load haul dump (LHD) vehicle typical of that used by the Australian underground coal industry. It was noted in testing that the technology increased modal NO2 formation, but was compliant over typical operational duty cycles.One of the key benefits with the use of a wall-flow DPF system is its tamper-proof design, mitigating the risk of operating unfiltered diesel plant in poorly ventilated areas. Elimination of the need for continual replacement of disposable filters provides significant operational savings estimated to be up to 80 per cent of the incumbent technology.In addition to the above, the project also delivered a number of significant contributions to the knowledgebase of the Australian and international coal industry with regard to the characterisation of operations and control of emissions.CITATION:Coplin, N, 2017. Wall-flow type diesel particulate filter system to replace existing wet element filter systems used in typical LHDs in underground coal operations, in Proceedings Australian Mine Vent Conference 2017, pp 119–128 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Barry C. Slocombe

The development of new ports, extensions of existing facilities and reclamation of former docks will involve consideration of a variety of geotechnical problems. This paper presents data including instrumentation of structures from three UK projects involving vibro techniques to provide economic engineering solution.

Jan 1, 2008

By Carnevale Francesco, Bracci Laudiero Alberto, Pampanin Piero

"SummaryIn the Port of Naples a slurry wall has been realized through a sandy layer up to a deep tuff layer using the Cutting Soil Mixing technique.The executed panels have dimensions of 2.8 m x0.65 m in plan and a total length of 25 m. Primary and secondary panels have been executed using the wet to wet technique. During the panels execution the following parameters had been measured: injection pressure, injected volume, verticality. At the end of the works an exploratory campaign has been carried out through boreholes collecting samples for laboratory tests in order to verify the diaphragm thickness and its physical and mechanical properties (i.e. unit weight, unconfined compressive strength).The interpretation of the collected data allowed to verify the efficiency of the method, the volume of slurry loss due to permeation during the panels execution, the quantity of the obtained spoil compared to the volume balance equation, both for the sand and the tuff layer.Eventually, the measured physical and mechanical characteristics of the panels have been correlated to the execution method performed.IntroductionIn the Naples Port area there is a polluted site which has to be hydraulically isolated in order to prevent the pollution of the groundwater that flows from land to the sea through the Port area. A hydraulic cut-off wall has to be realized and particularly a slurry-wall realized using the CSM method had been executed.To date, two stretches have been executed, 140 an 110 m in length respectively, as shown in Figure 1 and Figure 2.After execution, the slurry-walls have been investigated with boreholes. In-situ and laboratory tests on the recovered samples of grout have been carried out; furthermore, the geotechnical parameters of the mix composing the wall have been measured."

Jan 1, 2014

By Clarke DS

The igneous intrusions in SE Papua New Guinea are part of a sub-volcanic to plutonic, high-K calc-alkaline to shoshonitic suite. High-K andesitic to dacitic intrusives on Misima and Woodlark Islands, and shoshonitic intrusives in Milne Bay and the eastern Owen Stanley Ranges are related to late Cenozoic andesitic volcanism. Both suites are associated with epithermal Au-Ag deposits and weak porphyry Cu-Au mineralisation. All significant alluvial and lode gold occurrences in the region are spatially related to intrusions. Intrusions in the D'Entrecasteaux Islands and near Mt Suckling are core plutons related to basement doming, and appear to have no association with either volcanism or hydrothermal mineralisation. The core plutons are not petrochemi:ally distinct from the volcano-re:-ed Intrusions.

Jan 1, 1991

This paper focuses on two sites in the Mount Pleasant - McCormacks Bay area of Christchurch where residential development has taken place either within or immediately adjacent to former quarries for the extraction of volcanic rock. At the Quarry Road site less overburden was dumped on adjoining land around the turn of the century, and c.1980 dwelling and related construction took place on approximately 6 m of relatively loose fill material without the recognition of its presence or geotechnical characteristics. Subsequent settlements led to abandonment of a swimming pool and the underpinning of the 3-storey architect-designed house, whilst litigation brought by the owner resulted in findings of negligence against both the architects and engineers. At the Tramways Quarry site the Council approved subdivision of the former quarry area in the early 1980s without requiring any geotechnical evaluation of batter stability or related issues. During development it became apparent that significant blast damage had occurred to rock faces, necessitating a variety of remedial measures, and that waste materials had been dumped down faces without regard to long-term stability. Both case studies confirm the requirement for careful documentation of former quarry sites by territorial local authorities as part of their administrative function, and for detailed engineering geology and geotechnical evaluation of such areas prior to any residential use of the land.

Jan 1, 1998

By E. Hornbogen

The deformation mechanisms of a iron-phosphorus alloys were compared at 20oand —196°C. Alloying with phosphorus increases the resistance to slip, but has little effect on the resistance to twinning. The stress for onset of twinning is nearly independent of temperature, but there is an increasing tendency for cleavage along (112) twin boundaries with decreasing temperature and increasing phosphorus content. FIVE iron-phosphorus alloys and one high-purity iron (0.004 pct C, 0.004 pct N, 0.05 pct O) were vacuum melted and cast, then homogenized for 6 hr at 1100oC and water-quenched. Single crystals were cleaved from the coarse grains produced in this manner. The hardness was measured* on polished (100) surfaces of the crystals at 20" and -196°C. Laue back-reflection patterns indicated a deviation of not more than 3 deg from coincidence of the {100} plane with the surface. The deformation mechanisms were studied by relief effects on the polished surfaces. Yield points in compression (0.5 pct offset) were measured with polycrystalline material. At 20°C the addition of phosphorus to a iron leads to a change from slip to twinning as the main deformation mechanism, Figs. 1(a), (b). Between 2 and 4 at. pct P slip and twinning occur simultaneously. In alloys with more than 4 at. pct P twinning is the main deformation mechanism and slip was observed only in the neighborhood of twin intersections. All cracks at 20oC were on (100) planes, some initiated by twins.' From measurements made at-196oC, hardness and yield points of all the alloys were nearly constant and the same as the hardness of high phosphorus alloys that deformed by twinning at 20°C, Figs. 2 and 3. In the high-purity iron, plastic deformation at -196°C occurred by both slip and twinning, but deformation in the iron-phosphorus alloys appeared to be entirely by twinning. In the high phosphorus alloys a large number of cracks formed along the (112) twin boundaries and at intersections of twins, in addition to the (100) cleavage, Fig. 1(c). DISCUSSION In , iron, plastic deformation can occur either by slip or by twinning, depending upon composition,

Jan 1, 1961

By J. F. Butler, H. W. Paxton

The vapor pressures of manganese in equilibrium with several alloys in the iron-manganese-carbon system between 1200° and 1275°K have been measured using the Knudsen effusion technique in conjunction with a vacuum microbalance. The effect of orifice area of the effusion cell upon the measured pressure has been determined. The binary iron-manganese system shows small negative departures from ideality, and the system of mixed carbides, (Fe, Mn)7C3, in equilibrium with graphite behaves ideally. THIS work is a continuation of the investigations in which the Knudsen effusion method has been used to determine thermodynamic activities in systems and at temperatures of interest to metallurgists. In a previous publication,' the free energy of formation of Mn7C3 was determined and some preliminary work on the solution behavior of this carbide with the hypothetical "Fe7C3" was reported. The present work deals with this latter topic and also includes data on the binary ir-on-manganese system. EXPERIMENTAL METHOD The Knudsen effusion method was used to measure the vapor pressure of manganese in both the alloy and carbide sections of this investigation. This dynamic method of vapor pressure measurement presents a problem when studying solid alloy systems in which one of the components has a much larger vapor pressure than the others. Over-all depletion of the alloy in the most volatile component will occur during evaporation so that the pressure of that component will decrease. Even more serious than the over-all concentration change is the surface depletion of volatile component in the alloy brought about by the slow rate of diffusion of this component from the interior to the surface of the solid particle. Since knowledge of this surface composition is necessary in order to relate it to the activity determined through the measurements, changes in surface composition from the analyzed bulk composition are to be avoided in dynamic vapor pressure studies of solid alloys. The system under investigation in this study presents the problem of surface depletion of manganese since its pressure at 1230°K is 105greater than iron and 1020 greater than carbon. Since the existence of a volatile manganese carbide had been ruled out previously,' the high manganese pressure relative to iron and carbon insured that the only species leaving the effusion cell was manganese. Therefore, the effusing species required no analysis so that the manganese pressure was determined directly from the weight loss of the effusion cell. In order to detect small weight losses near the beginning of effusion, a vacuum microbalance was used to weigh the cell continually. These initial weight loss data allowed the rate of manganese effusion to be determined before the surface of the alloy became depleted in manganese. The apparatus used in this investigation is shown in Fig. 1. Temperature was measured using chro-

Jan 1, 1962

By P S. Heithersay, M McGeough

The discovery of Olympic Dam in 1975 and, more recently, Prominent Hill in 2001 and Carrapateena in 2005 demonstrates the potential for world-class IOCG deposits in South Australia. Potential for further discovery of large IOCG mineral deposits in the Gawler Craton and the Curnamona Province is high because of continental-scale pervasive iron-rich alteration, crustal-scale structural preparation and unique magmatic-hydrothermal conditions. Recent exploration successes point to the effectiveness of new exploration tools and technologies to locate this style of mineralisation under cover. The gold endowment of these orebodies located in South Australia exceeds 75 Moz, with further discoveries to come. The lead time between discovery and development of the multi-million ounce Prominent Hill copper-gold mine in less than seven years demonstrates how quickly this style of deposit can be brought into production in South Australia. Clearly these long-life, multi- commodity IOCG deposits mines are an immediate exploration and future growth opportunity for the gold mining industry to replace ever depleting gold inventories.

Jan 1, 2007

By Christopher J. Bise

PRINCIPLES OF MINE PLANNING During the initial planning stages, all mining operations are analyzed and evaluated in a similar fashion. This similarity holds true because the mine-planning procedure can be reduced to a network of interrelated systems that are tied together by a common philosophy of mine planning: namely, that the resource is to be extracted in a manner which is safe, efficient, and profitable. The success of the mining operation cannot be guaranteed unless each of these three requirements is met. Fig. 1 shows a flowchart for the initial planning of any mining operation. Notice that there is a preplanning stage that leads to the planning of four interrelated systems. The preplanning stage includes property exploration, estimation of production and manpower requirements, and the establishment of construction timetables. The four systems, evaluated after the pre-planning stage, are broken down into the following: (1) Excavation and handling system, (2) Strata control system, (3) Operating support system, and (4) Service support system. The Excavation and handling system includes the selection of all the equipment for the removal of the resource from its in-place deposit (e.g., draglines, continuous miners, rock drills, etc.) and for the transportation of the mined material from the face (e.g., belt conveyors, trucks, etc.). The Strata control system incorporates all those considerations which maintain the integrity of the roof, ribs, floor, and overburden both during and after the extraction phase; typical considerations in this area include pillar sizing, artificial support of the immediate roof in mine entries, and subsidence protection. The Operating support system contains the "necessary evils" of mine planning; the system consumes a large percentage of the mining engineer's planning time but does not contribute to the actual extraction of the resource. However, if proper attention is not paid to the various components of the system, such as ventilation, drainage, and power, then the mining operation will not perform to its capabilities. Finally, the Service support system is composed of those operations which keep the mine running efficiently; typical examples of these include maintenance and sup- ply. One important concept that Fig. 1 is designed to emphasize is that the four systems are interrelated; typically, a slight alteration of one can affect the performance of another. If these interrelationships are ignored, the effects on the system can be disastrous. The mine preplanning stage and the four subsequent system evaluations constitute the Analysis portion of the mine planning flowchart. After this portion of the study is completed, the overall projected operation can be evaluated by techniques such as financial analysis. This last step in the study is referred to as the Synthesis of the previously calculated parameters into an overall plan. Much has been written about the overall evaluation of mining properties, but, over the past thirty years, very little has been written about the analysis of mine- planning systems in a coordinated manner. Further, those texts which attempted this topic have failed to give sufficient examples for successful implementation, thus supporting the operating engineers' lament that it is easy to discuss theories but difficult to show applications. This text is intended to bridge this gap. Examples of the various stages of the analysis portion of the mine planning flowchart shown in Fig. 1 will be covered in this text, with the exception of the Service support system, since this system is oriented more toward day-to-day planning than long-term mine planning. INTERNATIONAL STANDARDIZATION The benefits that can be derived from an international standardization of the units used in mining engineering calculations are numerous. The interchange- ability of equipment parts and the ability to analyze and compare performance and design specifications on an equal basis are just two of the goals desired by both manufacturers and mine operators. Unfortunately, conversion to an international standard has not been rapidly achieved by engineers in the United States, due to their training under the English system. The Society of Mining Engineers of AIME has made the commitment for the adoption of the Systeme International d'Unites (SI) in all mining engineering calculations. Since many practicing mining engineers and students in undergraduate programs still find difficulty in relating to SI units, the calculations in this textbook will use the English system, with Table 1 available for conversion into SI units.

Jan 1, 1986

By D. R. Wilburn

The worldwide budget for nonferrous, nonfuel mineral exploration was expected to increase by 58 percent in 2004 from the 2003 budget, according to Metals Economics Group (MEG) of Halifax, Nova Scotia. The increase comes two years after a five-year period of declining spending for mineral exploration (1998 to2002). Figures suggest a subsequent 27 percent increase in budgeted expenditures from 2002 to 2003. For the second consecutive year, all regional exploration budget estimates were anticipated to increase. The worldwide budget for gold exploration achieved about 50 percent of the total amount budgeted in 2004.This was 68 percent, or US$715 million, higher than the reported 2003 budget. The 2004 worldwide exploration budget estimates for copper increased by 70 percent, orUS$237 million, to US$577 million from the 2003 budget. The budget for nickel exploration increased 52 percent, or US$89 million more than in 2003. The 2004 exploration budget for other mineral targets (primarily cobalt, heavy minerals, industrial minerals and silver) increased114 percent, or US$118 million.

Jan 1, 2005

By K. Shimamoto

This study has been prompted by the anticipated demand for rhenium by the petroleum industry and the concern for an adequate supply of rhenium to meet the demand. The present and projected outlook for rhenium relative to its distribution and occurrences, the recovery factors involved in ore beneficiation, capital and operating costs, changing technology, and the projected uses and market growth of rhenium are presented in this report as part of the Bureau of Mines program to determine the availability of recoverable rhenium in a developing market.

Jan 1, 1973

By William T. Boyd

Foreign mining publications describing successful hydraulic mining installations, and successful domestic hydraulic mining in a gilsonite bed, have prompted the Federal Bureau of Mines to conduct a literature survey of foreign publications to determine if the hydraulic mining method can be applied to domestic coal mining. Most foreign publications do not give detailed data about the water pressures, water capacities, and production and manpower requirements for successful hydraulic mining, However, they do provide enough general data on mining conditions, manpower, and equipment used to show that conditions in many bituminous coal deposits in the United States may be favorable for economical coal extraction, using high-pressure water jets. Therefore, the Bureau proposes to conduct a field investigation to determine the most appropriate natural conditions, water pressures, and equipment for successful hydraulic mining of coal beds in the United States with variable dip, thickness, and hardness. In the past, technical personnel reviewing foreign mining reports assumed that a steeply pitching coal bed was necessary for successful hydraulic mining. Although the structure of the coal bed may be a factor in gaining assistance from overburden pressures or help in an integrated hydraulic mining and transportation system, the coal is broken mainly by the action of high-pressure, water-penetrating cracks, fissures, or cleats; therefore, the slope of the coal bed is not necessarily a determining factor in hydraulic mining.

Jan 1, 1959

By Vincent A. Scovazzo

On March 12, 1994, the 1,100-foot deep 2 Yard South panel of the 1l0 year-old Retsof Mine collapsed. At the time of this occurrence, the Retsof Mine was characterized as the world's largest, most productive salt mine. The collapse produced a seismic event and resulted in a sinkhole and small lake forming on the surface. An existing highway bridge was rendered unusable. Water entered the mine and despite valiant efforts by the miners and the mining company, the entire mine was flooded and lost. John T. Boyd Company (BOYD) studied the incident to evaluate design procedures, and assess the short- and long-term environmental impacts of the collapse. This paper presents our analysis of the cause of the collapse and our review of the rock mechanics design of 2 Yard South panel. Our review is, in part, based on a rock mechanics monitoring program of 2 Yard South. The monitoring program was established by the mining company as the panel was developed and continued even after the panel became unstable.

Jan 1, 1997

By R. Clarkson

"The Yukon's numerous (185) placer gold mines are still a major social and economic force in this developing economy. Gold recovery at each of the various sluiceboxes is not optimized due to extremely difficult sampling logistics and a shortage of technical expertise and industrial research.At each of six operating placer mines, numerous sluicebox tailings samples were collected with hand held sample cutters and combined into large (2-7 cubic yards) duplicate samples. The entire sample volumes were screened and processed on a shaking table to determine gold losses. The existing and potential gold recoveries and recommended sluicebox design and operating parameters are presented.2 ACKNOWLEDGMENTSThe Project Manager gratefully acknowledges the following support for this placer research program:The funding received from the National Research Council's Industrial Research Program, the Canada/Yukon Economic Development Agreement and the Canada Center for Minerals and Energy Technology (CANMET): andThe technical advice provided by Tad Cienski (CANMET), Ron Johnson (KPMA), George Poling (University of B.C.) and Dan Walsh (University of Alaska).3 OBJECTIVESThe objectives of the Gold Recovery Project are to: evaluate gold losses with statistically based sampling programs; determine how to improve gold recovery; assist miners with the recommended technology and make this information available to the entire placer industry."

Jan 1, 1990

The Takasima Coal Mines comprise four islands near the entrance to Nagasaki Harbour, and are owned and worked by the Mitsu Bishi Company.There are several unusual features in the occurrence and working of these coal seams, the steep angle of "dip," the numerous seams of good coal separated by hundreds of feet of sedimentary rocks, the extensive faulting of the strata, and the way in which the coal is won, when so little surface is available for works, and where there is the ever present danger of subsidence of the roof and consequent flooding of the workings by the ocean. The author trusts that short notes on these few points will be of interest to members.The Islands are named respectively Hasima (Extreme Island), Nakanosima (Middle Island), Takasima (High Island), and Yokosima, and are situated about one mile from the main land.

Jan 1, 1901

By Malcolm Ross

The Reserve Mining Co., in the processing of taconite iron ore quarried from the Peter Mitchell Pit, deposited the finely crushed waste rock into Lake Superior near Silver Bay Minnesota. In the early 1970s The U.S. Environmental Protection agency filed a lawsuit against Reserve Mining Co., asking the court to force the company to stop dumping into the lake. On April 20, 1974, after a lengthy court battle, the U.S. District Court concluded that the Reserve Mining discharge into Lake Superior violated federal and state pollution laws and thus ordered Reserve Mining Co., to halt the lake disposal of taconite tailings. At the time many feared that some of the mineral particles contained in the tailings (alleged to be asbestos or asbestos-like) would cause human health problems. This Conference was thus convened to readdress the problem of the mineral content of the Biwabik Iron Formation and to whether any minerals contained in the ore could cause human disease. The four papers given in this session address the nature of the mineral particles in the taconite rock, the definition of the term ??asbestos?? and the history of the legal controversy over the possible health effects of certain mineral particles contained in the Biwabik iron range ores. Paper 1?Geology of the Biwabik Iron Formation and Duluth Complex Mark A. Jirsa, James D. Miller, Jr., G.B. Morey The Biwabik Iron Formation was a principal source of ore for the American steel industry during the 20th Century. The unaltered iron deposits, called taconite, contain approximately 30% iron and 50% SiO2. About 75% of the iron in taconite resides in the mineral magnetite, the remainder is largely in iron carbonate and several iron-silicate minerals.

Jan 1, 2007