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The scale and seriousness of AustraliaÆs social and environmental problems are no longer in doubt. We are consuming the opportunities of future Australian generations by our lifestyle choices. And at the global level, human activities are altering the very systems on which our species depends. Doing nothing about such problems as climate change is not an option. It is possible to move to a sustainable future but it will require fundamental changes to our values and national social institutions. We must recognise that we share a common future with the entire human family and the other species with which we share the planet. It is not just our humanitarian duty to improve the lot of the poorest people of the world. It is also enlightened self-interest because a world of increasing inequality will be a world of increasingly destructive tension.

Jan 1, 2004

By D. B. Apel

Rock mechanics software plays an important role during the design process of modern underground mines by allowing for verification of the stability of the planned excavations. The paper describes the methodology used to plan and locate the permanent underground openings at McArthur River Mine with the assistance of numerical modeling software.

Jan 1, 2004

By S. Dessureault

Integrated information technology infrastructure is the linking of data across various applications throughout a business to gain further data-driven improvement opportunities. Decision support systems (DSS) are the various improvement opportunities that facilitate decision making for a potential optimal outcome. Integrating tera-bytes of data spread throughout a business is complex. There are tools to facilitate the development of such data-driven DSS. This paper analyzes the various tools that may facilitate the development of complex data-driven decision support systems, namely; information models, business models, data utilization model, and testing environments. A case study is presented to demonstrate how these tools facilitated the development of an automated activity-based budgeting DSS at a large-scale underground mining complex.

Jan 1, 2004

By M. Reza Bateni, M. Zandrahimi, J. A. Szpunar

Titanium aluminides and nickel aluminides offer the potentials, as coating materials, for high temperature and aerospace applications. In this research, attempt has been made to develop Al-Ti and Ni-Al intermetallic compound coatings on the surface of Inconel 738. The coatings applied through pack cementation and simultaneous diffusion annealing processes. Scanning-electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDAX) and grazing angle X-ray diffraction were used for evaluating of coating structure. It was demonstrated that the pack cementation technique could be used to develop TiAl3 and AlNi intermetallic compounds coating on Inconel 738 substrate. When pack cementation technique is based on a halide-activated pack with aluminum and titanium powders, the coating consists of TiAl3 intermetallic compound phase. Whereas, by pack aluminization of Inconel 738, the coating consists of AlNi intermetallic compound phase.

Jan 1, 2004

By I. J. Kotzé, R. T. Jones

Conventional PGM matte smelting requires the presence of a certain quantity of base metal sulphides in order to collect the platinum group metals in a molten sulphidic matte phase in the furnace. Furthermore, the quantity of chromium oxide in the feed materials is controlled in order to avoid the build-up of high-melting chromite spinels in the furnace. Mintek has developed a process for smelting difficult PGM-containing feed materials that contain low amounts of sulphur and/or high amounts of chromium oxide. A DC arc furnace is used to provide the appropriate conditions to generate an iron alloy that collects PGMs very effectively, leaving extremely low residual quantities of PGMs in the slag. Various feed materials have been treated successfully in furnace campaigns running at power levels up to 1.5 MW. The longest of these campaigns was run continuously for more than four months, treating more than two thousand tons of materials such as low-grade concentrates, revert tailings, and converter slag. The campaigns demonstrated the robustness and versatility of the process, and proved that it is possible to sustainably produce a PGM-containing alloy and discardable slags containing an average of less than 1.4 g/t of PGMs over the entire campaign. Keywords: DC arc, smelting, furnace, platinum, PGM, revert tailings, converter slag, ConRoast

Jan 1, 2004

By Richard J. Mainiero, Marcia L. Harris, James H. Rowland

In the past several years, there have been a number of blasting-related carbon monoxide migration incidents. In each case, there have been some common factors that appear to be related to carbon monoxide migration. Geology, heavy confinement of the blast, close proximity to the affected structure, and open pathways into the affected structure are just a few. Prince William County, VA is an area undergoing a boom in suburban development. In the year 2001, more than 4,050 new homes were constructed within the county.1 In the new housing development located in Bristow, VA, trench blasting was utilized to excavate proposed sewage and utility lines. On November 8, 2002, a trench blast was conducted for the installation of utility lines. Later that evening a carbon monoxide detector alarmed in a nearby house. The gas company and fire department sampled for carbon monoxide and measured 100 ppm and more than 200 ppm on the first floor and in the basement respectively. Subsequent efforts to prevent migration of CO into the nearby homes met with mixed results. The only reliable technique for protecting neighbors from CO appears to be the placement of CO monitors in the homes. The events are presented and discussed.

Jan 1, 2004

By T. Gerritsen, A. Matyas, F. Stober, I. Candy

This paper describes developments in ferro-nickel furnace technology, specifically improvements to cooling methods, furnace controls, and high voltage furnace operating regime. The evolution of these technologies is briefly presented, as context for describing the current state of the art that has enabled ferro-nickel furnace operation at over 75 MW and specific energy consumption of less than 400 kWh/t dry ore. Examples from existing operations are used to illustrate present best practices, and potential future trends are discussed. The paper begins with an overview of the fundamental aspects of pyrometallurgical treatment of lateritic ores that drive ferro-nickel furnace design. Furnace wall cooling methods are related to the requirements resulting from specific furnace process conditions, including slag and metal compositions, as well as arc and bath power. The benefits of high productivity and low specific energy consumption resulting from high voltage (shielded-arc) operating practice are discussed, along with the furnace controls and electrical power train that enable such operation even with captive power generation.

Jan 1, 2004

By R. Boom, J. Halder, B. Snoeijer, B. Deo, A. Overbosch

Operational data of BOF and the slag samples for different starting conditions of phosphorus(0.06–0.26 per cent P) and silicon content (0.3–1.2 per cent Si) of hot metal have been analysed. The contribution of parameters that are well known to affect phosphorus distribution at tap, like basicity, temperature, FeO content of slag, slag mass etc., is investigated through the models of ionic theory of slag, optical basicity, regular solution approach and molecular theory of slag. The best overall results are obtained by the model based on molecular theory of slag in which several operational parameters are also incorporated. The investigations of different slag samples, based on optical, SEM, EPMA and X-ray studies, reveal the effect of MgO and Al2O3on slag morphology and phosphorus distribution in different phases. It is important to consider phosphorus distribution ratio in the solid and liquid part of slag. The solid part of slag, which is mostly dicalciumsilicate, can contain up to 5 per cent phosphorus. The phosphorus content of the liquid part of slag may depend upon the phosphorus content of hot metal or phosphorus load of slag. It is found that incorporation of effect of dicalciumsilicate in the model improves the accuracy of prediction. For better process control, the addition of iron ore towards the end of blow must be avoided while treating high phosphorus hot metal or during the production of ultra low phosphorus steels. Keywords: steelmaking, BOF, phosphorus distribution, slag morphology, MgO, Al2O3,dicalciumsilicate, process control, models

Jan 1, 2004

By Andrea R. Gerson, Roger St. C. Smart, Russell Schumann, Joan E. Thomas, Warwick Stewart, Stuart Miller

Sequential Net Acid Generation (NAG) accelerated oxidation testing using peroxide was carried out on single sulfide mineral samples. The calculation of the nett acid production potential (NAPP) assumes that all the sulfide is present as pyrite and that dissolution results in a 2:1 ratio of H+:SO42-. NAPP as kg H2SO4/t is calculated as 30.6 x wt.% S present. To test whether this calculation is valid a NAPP* value was defined in which instead of using the wt.% S present for the calculation the wt.% S dissolved is used. Stoichiometric analysis of the dissolution products of the sulfide minerals as they would occur at pH 7 indicates, that in all cases, the ratio of H+:SO42- of 2:1 is viable. The NAG to pH 7 and NAPP* closely coincided for pyrite, bornite, chalcocite and covellite. For the three Cu-containing minerals, the NAG to pH 4.5 value was 0 as is predicted on the basis of the speciation likely to be present at pH 4.5. Acid generation is due to hydroxylation of the dissolved Cu between pH 4.5 and 7.0. The NAG to pH 7 and NAPP* values for chalcopyrite, arsenopyrite and pyrrhotite were in reasonable agreement but were not for either sphalerite or galena. Zn is not completely hydroxylated at pH 7 as is assumed by the calculation. For galena, surface analysis identified polysulfide formation on of the leach residue polysulfide. The formation of polysulfide is an acid consuming reaction. Therefore under conditions of accelerated oxidation the NAPP value is a reasonable estimate of the possible acid production in all cases except for sphalerite and galena. However, under conditions of less intense oxidation, for instance in columns, waste rock and tailings dumps, the formation of polysulfides is likely to be more widespread thus reducing the correlation between NAPP and the maximum possible acid production.

Jan 1, 2004

Mining engineering, metallurgy and minerals-related geology have proud traditions and are essential professions to support a safe and sustainable minerals industry. However, the future of these professions is under threat. The courses that produce such graduates are disappearing worldwide and the number of graduates available to enter the industry has been falling in English speaking countries for at least a decade. It is unlikely that this problem will be remedied by æsupply and demandÆ. Instead, some active intervention is required.

Jan 1, 2004

By D. Lascelles, J. A. Finch, E. El-Ammouri

Flotation separation is expected to be related to the degree of dispersion of the pulp. For instance, highly aggregated systems may show reduced selectivity, reduced entrainment and increased flotation rate. In an attempt to test the impact of aggregation on flotation, we have taken advantage of the effect of Mg ions. Using combinations of Mg2+ and pH gave a wide variation in aggregation of several Cu-Zn ores (measured by settling rate) and corresponding flotation response was determined by batch tests. The trials were conducted on-site at Louvicourt and Agnico-Eagle. In a majority of cases a similar trend in aggregation and flotation selectivity (grade at given recovery) was observed. At Louvicourt, improved selectivity with increasing aggregation at pH 10.5 was found. At Agnico-Eagle, an analogous association between aggregation and selectivity was observed at pH 11.5. It is suggested that aggregation influences particle entrainment, the increased effective particle size reducing gangue recovery and hence improving selectivity.

Jan 1, 2004

By J Kwak

Driving sustainability concepts and practices into the heart of the design process is the key to achieving a successful, sustainable plant design. Engineering design practices, tools, systems and methodologies should be prepared around true eco-efficiency parameters, adopt wholesystems-thinking and consider life-cycle impacts for the design task. Experience dictates that the application of sustainable plant design practices is most likely to succeed if: The principles are well documented and explained. All stakeholders agree on what sustainability means. Sustainable plant design is treated as a core process. The principals of sustainable plant design are equally applicable in brownfield and Greenfield environments. Although brownfield situations provide the designer with less latitude for change, these types of projects do allow easier measurement and demonstration of relative impacts. This paper further develops the above points by drawing on case studies from HatchÆs repertoire.

Jan 1, 2004

By L. Arnberg, E. Ott

The microstructure of ferrosilicon is important since it controls the disintegration of the material during crushing and thus the generation of fines. Therefore a study of the microstructure formation during solidification of pure FeSi(75wt%Si) and FeSi(75wt%Si) containing 1.2wt%Al and 0.2wt%Ca has been initiated. The material has been cast into rods of 8mm diameter, which have been remolten by induction heating and directionally solidified in a Bridgman apparatus. This allows the temperature gradient and the growth rate to be controlled independently. The temperature history during solidification has been recorded by a thermocouple in the melt. Growth rates have been varied between 5 and 400µms-1 and temperature gradients between 3 and 14°Kmm-1. The microstructures show a large dependence on the solidification conditions. The crack formation in the alloys has been studied and found to be strongly related to the microstructure.

Jan 1, 2004

By Charles A. Weinstein

INTRODUCTION As a set of management practices, "Knowledge Management" (KM) has disappointed many of its early advocates. The core notion behind KM can be summed up in the oft- quoted adage, "If we only knew what we know." KM describes a set of tools, practices, and approaches for using data, information, and expertise-knowledge-resident in an organization to improve the performance of that organization. The idea was incubated, hatched, and grew among some the largest and most successful companies in the world. Some of these companies created "Chief Knowledge Officers." Many more collectively invested billions in a huge range of KM efforts, all designed to use their organizations' information and expertise to innovate, improve margins, sell, or accomplish any of a myriad of sound business goals. Some KM efforts were successful, and many were not.* Today, it is indisputably the case that KM as a named set of practices has fallen out of favor. Why, then, should KM be discussed at a conference on "Things that Actually Work" for plant operators? Because, in many instances, KM has actually worked. The practices that represent KM done right offer significant opportunities for plant operators to achieve real gains, especially in times of resource constraints and in the face of ever-increasing technical and commercial goals. The KM fad is all but over. The KM benefits continue to accrue to those who have applied the lessons learned from that fad, and implemented sound * Fair disclosure: I am not unbiased with respect to the potential impact of KM. Teltech has been a pioneer and leader in KM, both as a practitioner and as a leading consultant to other organizations.

Jan 1, 2004

By Sam Kangwa, Thomson Sinkala

In the mining industry, drilling accuracy has a significant effect on the economy of operations. In this paper, results from the Nkana Division of the former Zambia Consolidated Copper Mines are presented. For the stope investigated, it was found that the extra operational costs alone were 462% of the planned costs! Clearly, there is more than good reason to pay attention to drilling of good quality holes.

Jan 1, 2004

By V. I. Zhuchkov, L. A. Smirnov, E. I. Arzamastsev, A. A. Babenko

A brief analysis is given for state-of-the-art of manganese and chromium ferroalloy production in Russia and their consumption by metallurgy plants. The main causes of low output of manganese and chromium ferroalloys, and ways to resolve the issue of ferroalloy production development are considered.

Jan 1, 2004

By S. E. Olsen, K. Tang

The complex heterogeneous equilibria associated with the production of manganese ferroalloys have been simulated by employing recently developed thermochemical databases. The non-ideal Mn-Fe-Si-C alloy and the MnO-SiO2-Al2O3-CaO-MgO-FeO slag system have been modelled separately by the compound energy and cellular model. A large number of experimental thermodynamic and phase-equilibrium data were used to evaluate the model parameters for the liquid and solid Mn-Fe-Si-C phases. In addition to the liquid metal phase, solid mixture phases occurring in the Mn-Fe-Si-C system have also been studied. Over 500 measured equilibrium data have been utilised to verify and calibrate the model calculations. The paper will present typical simulation results, from activities of components to multicomponent heterogeneous equilibria. Good agreements can be obtained for many important technological parameters such as carbon solubility, phase relations and equilibrium diagrams, element distribution as function of temperature and slag composition etc. Application of the present models to the silicomanganese production will be demonstrated in this paper.

Jan 1, 2004

By N. A. Barcza

This publication records the proceedings of the Tenth International Ferroalloys Congress, INFACON X, and the third INFACON hosted in South Africa. The Proceedings of the previous two South African congresses in 1974 and 1992 serve, as this volume does, as a valuable record of the papers presented at these important events. This publication comes at a time in South Africa?s democratic development where the theme ?Transformation Through Technology? is very appropriate. The ferroalloy industry has played an increasingly significant role in transformation and black economic empowerment in South Africa, particularly through the advancement and sharing of technology. INFACON X plays an important role in this process, and the stakeholders and organisers of this Congress are thankful for the opportunity to hold this event at this time of transformation in our country. The world of ferroalloys, as well as that of the steel and stainless steel industries, has continued to change rapidly. Recent innovations, better use of resources, increased awareness of environmental issues and ongoing efforts to improve occupational health and safety are among the topics addressed at INFACON X and in these Proceedings. The theme of ?Transformation Through Technology? has been chosen to reflect the regional and global developments in the ferroalloy industry, and the crucial role that technology plays. The Proceedings of INFACON X, the first Congress in Southern Africa of the new millenium, represent a milestone in the technical developments in this major global industry. It contains almost eighty papers in twenty Sessions, from authors in twenty countries, covering raw materials, reductants, energy, electrodes, refractories, furnace design, post taphole services, modelling, simulation, control, sensors, fundamental issues and the applications of ferroalloys as related topics. The major ferroalloys, namely ferrochromium and ferromanganese, are covered extensively in many interesting papers. This comes as no surprise, since South Africa is the leading producer of ferrochromium and also plays a major role in the supply of manganese ore and alloys. Papers on ferronickel, silicon and ferrosilicon ensure that all the large-volume ferroalloys are addressed. These Proceedings of refereed papers of high quality will serve the ferroalloy industry for many years to come, as has been the case with previous INFACON events. For the first time in the history of INFACON, the Proceedings will be available both in bound and in a searchable electronic CD-ROM format. We appreciate the time and effort that the authors and referees have devoted to making this publication a really valuable document. Their contributions are recorded for posterity and reflect the advancements they and their colleagues have made to benefit the ferroalloy industry. Without these ongoing improvements, the industry would stagnate and not fulfil its role in the advancement of mankind. All papers included in these Proceedings were peer-reviewed by at least two referees. About 130 referees were sourced internationally to fulfill this function, and their valuable technical and editing inputs are gratefully acknowledged. Finally, I would like to thank the Technical Programme and Publication committees, led by Dr. Lloyd Nelson and Dr. Noël Machingawuta respectively. Without the tireless efforts of these individuals and their Committee members, the technical programme and these Proceedings would not have been the success they certainly are.

Jan 1, 2004

By Fred Baldassare, Marcia Harris, Kenneth K. Eltschlager

Surface mine blasting was recently investigated as a potential source of high concentrations of stray gases found in nearby residences of western Pennsylvania. In one incident carbon monoxide was detected in a home and in the other, high concentrations of carbon dioxide were found in a home. Both carbon monoxide and carbon dioxide are by-products of blasting. However, other potential sources of these gases may also exist in a residential setting. In each case, gas chromatography (GC) and carbon isotopic analyses were used to define atmospheric concentrations inside the homes, and to determine the source of a stray gas. Molecular and isotopic analyses provide geochemical evidence as to the origin and source of the stray gas. This paper discusses elements of a stray gas investigation and the analyses necessary to identify the source of a stray gas.

Jan 1, 2004

By Maria I. De Rosa

Table 1 and figure 1 show the number of fires and fire in¬juries that occurred in underground coal mines by state during 1990-1999. Table 1 also shows by state the risk rates, employ¬ees' working hours, lost workdays, and coal production. Over¬all, 87 fires occurred in 12 states. Twenty-seven of those fires caused 34 injuries (the yearly average was 8.7 fires and 3.4 injuries). One fire and one injury involved a contractor. The underground mine fires required 25 mine rescue team interventions and 30 mine/section evacuations followed by 13 mine/section sealing/flooding/CO2/N2, gas injections. The Ewhr value was 1,003 x 106 hr (In = 0.007), the CP value was 4,008 x 106 st (Frr = 0.022), and the LWD value was 208. Virginia had the most fires (15 fires and 7 injuries). Pennsyl¬vania had the most fire injuries (12 fires and 9 injuries), fol¬lowed by Kentucky (12 fires and 6 injuries), and Alabama (12 fires and 4 injuries). Among these states, Alabama had the highest fire risk rate value (Frr = 0.073), whereas Pennsylvania had the highest injury risk rate value (In = 0.016). Table 2, partly illustrated in figure 2, shows by time period the number of fires, fire injuries, risk rates, employees' working hours, lost workdays, and coal production. The number of fires and fire injuries show a decrease followed by an increase during the five time periods (see table 2 and figure 2). This was ac¬companied by a decline in employees' working hours throughout the periods and an overall small decrease in coal production. The In and Frr values follow patterns similar to those shown by the fire and injury values. By comparison, data from Pomroy and Carigiet [1995] show that during 1978-1992 a total of 11 states were involved in 164 underground coal mine fires (yearly average, 10.8) with 43 injuries (yearly average, 2.9) and 27 fatalities (yearly average, 2; however, the 27 deaths occurred during a single fire caused by an overheated air compressor [MSHA 1984]). The CP value was 5,340 x 106 st (yearly average, 356 x 106 st) (Fn = 0.031). Data on employees' working hours and injury risk rates were not available. Tables 3-8 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 3 shows the major variables during 1990-1999. Table 9 shows the number of fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004