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By Andrew Burton, Damian Schofield, Jeremy Noond

This paper will introduce and discuss a range of techniques that utilise new developments in Computer Graphics (CG) and Virtual Reality (VR) for the investigation of incidents and accidents in mining environments. The future of mining safety may not be totally led by the demands of the mine operators, but sometimes by the academics, commercial software developers and legal pioneers who generate new ideas and products and set admissibility precedents which may change the way certain traditional investigative operations are performed. In any accident investigation the outcome from the investigating team is often a complex affair and the results of the investigation are often reported in large, convoluted documents. Computer-generated forensic reconstructions allow investigators to present accident scenarios in an accessible and easily understood, visual manner. Surveys in the US have also shown that people have increased recall of computer-generated images over many other forms of evidence. The AIMS Research Unit in the UK have been pioneering the use of Computer Graphics (CG) and Virtual Reality (VR) technology for both industrial and road traffic accident reconstruction. This paper and accompanying presentation will contain examples of forensic reconstructions developed by the authors that explain some of the methodologies used to ensure admissibility of this type of digital evidence. The paper will contain a number of case studies based on UK and International industrial accidents. The paper will focus on how AIMS Research is extending the capabilities of the accident reconstructions created to take advantage of the latest developments in VR technology. As digital technology makes its impact within professional and commercial fields, computer generated forensic reconstructions will form important admissible evidence in the courtrooms of the future. The technology will also make a great impact in the way we train our workforces, with highly visual three-dimensional (3D) interactive training tools becoming the norm. Acceptance by the public, courts and workforce is an important issue, and implementation strategies must be considered carefully.

Jan 1, 2002

By Andrej Šubelj

The paper tries to determine all which are interested or involved in collecting, evaluating, processing and distributing data on mineral resources, either "economic" or "uneconomic" and for what purposes. It shortly describes some of the most known classification systems, CMMI and UNFC, and their features, and discusses their advantages and weaknesses. Author also tries to define all the properties, a system should have to be declared as "World Code". Perhaps the ,integration of both systems would best accomplish the task and leave the “interest groups" the freedom to use only those parts of the system, they are interested in.

Jan 1, 2002

Your thoughts on the current status of the global minerals industries? The global economic, technological, social and political changes of the last two decades of the 20th century resulted in the emergence of a restructured minerals industry. This industry is now based on a new cost-cutting philosophy; utilization of modern technology; productivity gains rather than production tonnages; diversification of mineral markets; and globalization of exploration, mining and processing. Quantity and tons used to be the focus. The emphasis today is on remaining competitive in the marketplace by lowering per-unit production costs as much as possible. What factors and trends will impact the minerals industries in this, the 21st century? A number of parameters will impact minerals operations and shape the future sustainability and growth of the minerals industries. Increased demand for minerals will be accompanied by the demand for technical advancements. We will also see a continued emphasis on health and safety, environmental stewardship, and education and training. Let me elaborate.

Jan 1, 2002

By Joao Felipe Costa, Jair Carlos Koppe, Alexandre Grigorieff

Discrepancies in raw materials properties informed by both producer or consumer is a common problem in most areas of the industry. Commercial contracts in the mineral industry normally penalises the producer, if contaminants in the ore exceed established limits. In some situations, the supplier is penalised if the quality of the ore is below a contracted amount. Differences in lab analysis are due many sources of error, such as distinct practices used in two laboratories for sampling, preparation or analysis. Rigid contracts impose to the miner the use of rigorous quality control program and in these situations sampling plays a major role. Sampling theory provides the tools to analyse errors involved in sampling, preparation and analysis. This paper proposes a methodology to check the precision and accuracy of a given sampling protocol emphasising the application of Gy's sampling theory to broken ore. A procedure to measure the error on each step of the protocol is introduced and the results compared to the fundamental error measured by Gy's theory. The results show the applicability of the method and its relevance to audit sampling procedures aiming at error minimisation. The methodology is illustrated in a case study at a major coal producer in Brazil.

Jan 1, 2002

By Ross D. Lawrence

Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of generally accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.

Jan 1, 2002

By J. L. Yordan, J. Kortmeyer, I. Yildirim

Talc is used to remove stickies from pulp during paper recycling processes. It is well known that the interaction is controlled by the surface chemistry at the talc/water, sticky/water and talc/sticky interfaces. If the interfacial tensions are known, one can calculate the free energies of interaction and hence predict whether the stickies can be removed by talc. In the present work, the surface tensions of several different talc samples were determined using the acid/base theory. The information was then used to determine appropriate interfacial tensions, which in turn were used to determine the free energy of interaction between talc and stickies. It was found that the calculated free energies are much more negative than those between the stickies and other minerals such as calcium carbonate, bentonite clay and kaolin clays.

Jan 1, 2002

By G. S. Austin

The St. Cloud Mining Company extracts clinoptilolite about 6.5 km south of Winston, Sierra County, New Mexico. Production is about 18,000 mt/year. Natural zeolites are good adsorbents for positively charged solutes such as ammonium. St. Cloud’s production is used in animal hygiene, animal feed, environmental mitigation, air and water filtration, and other applications. By a simple chemical treatment with a surfactant, zeolites can also be modified to adsorb negatively charged solutes such as nitrate and arsentate, and neutral organics such as solvents and fuel components. These surfactant-modified zeolites are used in treating groundwater contamination, stormwater runoff, and solvent vapors from painting operations.

Jan 1, 2002

By N. S. Margaris

The vegetation of Mediterranean ecosystems is distinguished by its resistance to adverse environmental conditions, and that is the reason for examining the possibility of growing species of this flora in waste disposal sites (WDSs). The survival and growth of vegetation established at a waste disposal site is dependent to a large extent on the qualitative and quantitative characteristics of the material used in the final soil cover. In the Ano Liossia WDS, where extensive remediation work is under way, three areas were examined, which met certain criteria in relation to the age of the underlying waste and the existence of impermeable material in the final soil cover. Laboratory analyses have determined soil parameters and nutrient and heavy metal content. Alongside this, at all three sites a network has been installed to monitor the qualitative characteristics of the gaseous phase of the soil cover material. The results showed the existence of a soil material containing few nutrients and the prevalence of oxygen-poor conditions, accompanied by large concentrations of CH4, CO2 and H2S, at depths of up to about one meter.

Jan 1, 2002

By Kostas Fytas, Sebastien Perreault

This paper presents EOLAVAL, an integrated mine ventilation design software. In its new expanded version it is a user friendly and fully interactive computer package. The features of the new version are a graphics interface fully compatible with Autocad files, an integrated database of fan characteristics and the optional use of the thermodynamic approach in carrying out network simulations. This software can be used in underground mine ventilation planning: mine ventilation network analysis and simulation, economic design of airways, auxiliary ventilation design, calculation of a mine air heating plant, and evaluation of the natural ventilation and pressure losses in a mine shaft. This paper presents a case study illustrating the use of the computer package in mine ventilation design.

Jan 1, 2002

By Vaughn Astley, Hassan El-Shall, Ponisseril Somasundaran, Regis Stana, Patrick Zhang

In the past, when phosphate rock quality was good, few paid attention to any of the impurities or other qualities associated with phosphate rock. In general, they had little or no effect on the ability to make the phosphate products for the market. However, as phosphate rock quality declined, it was apparent to the rock consumers that the individual impurities had a significant impact on their processes. FIPR is presently funding an analysis of operating plant data to determine the range of the effects of rock impurities on production plant performance. The study will not be completed until 2002. IMC has agreed to share some of the information they had developed in the early 1990s.

Jan 1, 2002

By B. P. Atkin, D. W. Brown

A handleability monitor was designed to provide a simple, rapid, on-site assessment of the whole or part consignment of a coal blend in its "as-received" condition. The monitor was evaluated at a number of coalhandling plants, which handle both metallurgical and power station coals from a variety of sources worldwide. The results can be used to predict which coals could routinely pass through a handling plant at line capacity without causing blockage or delay. Despite extensive analysis of the data, it was not possible to correlate the handleability index to the regular sample analysis of moisture, ash and size analyses of the coal blends.

Jan 1, 2002

By Roland Hoet, Jim Patilla, Nick Madison

Increasing conveyor capacity and reliability is a common goal for many underground mines. This task is especially challenging when you must work with existing structure, belt, etc. Meeting this challenge, The Pittsburgh & Midway Coal Mining Co. North River Mine switched from constant fill to actively controlled fluid couplings, realizing a capacity increase from 2,100 tons per hour (2,300 stph) to 2,550 tons per hour (2,800 stph), with improved reliability. This paper will present a case study of The Pittsburgh & Midway Coal Mining Co.'s North River Mine underground conveyor haulage system. These conveyors included the main line conveyors as well as a tension controlled tripper booster panel conveyor. Characteristics and performance of the coupling and control system will be illustrated, demonstrating the systems controllability, simplicity, and dependability.

Jan 1, 2002

By Salama

In the conventional approach, the separator feed incremental masses are assumed to be concentrated at the midpoints of the density or size intervals and subjected to a model partition function. The resulting separation predictions would change if the locations of the incremental masses were changed. As a result. the predicted results depend on the choice of locations where the feed incremental masses are concentrated in the density or size intervals. A technique that utilizes the cumulative-mass-distribution of the circuit feed and the derivative of the partition (separation) function relative to density or size variables is proposed. The proposed technique eliminates the dependency of the predictions on choice of where the feed incremental masses are concentrated within the density or size intervals. Since the proposed technique is based on the cumulative masses at the upper limits of the density or size intervals, the technique produces a single prediction whereas the existing techniques produce predictions that depend on where the incremental masses are concentrated. In fact, it has been demonstrated that the existing conventional technique, in which the incremental masses are concentrated at the midpoints of the density or size intervals, is a first-order approximation of the technique proposed.

Jan 1, 2002

By T. Stuczynski

In the past ten years about 3000 wastewater treatment plants have been built in Poland. The result of this development has been a massive increase in overall sludge production. According to data supplied by the Ministry of Environmental Protection, 400,000 dry tons of sludge are generated every year in Poland (Koblak-Kalinska 1996). Still it is difficult to estimate the amount of sludge, which is used in agriculture or for reclamation purposes. However, it can be assumed that this comes to no more than 10 percent of all sludge produced in Poland on a yearly basis. Thus it became obvious that an urgent solution to this problem was needed. Local authorities in Silesia realized in the early 90?s that a demonstration was necessary to encourage the proper utilization of sludge. This was the basis for establishing the Biosolids Subpart of the Silesia Project, which addressed the use of biosolids in the reclamation of mining and smelting dumps (Stuczynski et al. 1996). Metal waste sites themselves are known to contain more than 87 million tons of waste (Pistelok et al. 1995). Each year this amount increases by approximately 400,000 tons. We realized that a simple solution for stabilizing these sites would be to cover them with vegetation in order to reduce leaching of toxic elements, as well as to keep metallic fugitive dust from entering the environment. The reclamation of smelter waste sites, which was carried out within the framework of the Silesia Project was a joint effort of local government, industry and international research institutions/agencies, including the US Environmental Protection Agency (EPA), the Center for Research and Control of the Environment (OBIKS), Virginia Polytechnic Institute and IUNG. One of the goals was to evaluate the possibility of adapting the rules of sludge management currently used in the United States to conditions commonly found here in industrial regions of Poland. However, the main objective of the Silesia Project was the development of guidelines concerning all aspects of sludge use for the reclamation of degraded lands and waste sites. Biological aspects related to reclamation of metal waste with the use of biosolids will be discussed in this paper.

Jan 1, 2002

By Jacques Villeneuve, Stéphane Brochot, Jean-Claude Guillaneau, Marie-Véronique Durance

Since 1986, BRGM has been developing a powerful process simulation software package, USIM PAC. These last years have seen significant developments in mineral processing technologies, particularly in hydrometallurgy, bio-hydrometallurgy and mineral liberation. The new version of the simulator, USIM PAC 3.0, incorporates these modem-processing fields. Its structure and tools allow the user to take into account, at the same time, a wide range of technological, economical and environmental aspects. The improvement of the existing features and the introduction of new unit operation mathematical models and tools such as the supervisor, global optimization, workshop model or chemical reactions contribute to a global approach in mineral processing design.

Jan 1, 2002

By B. K. Mishra, R. K. Rajamani, A. D. Joshi

The liners are the most important part in the SAG mill operation. Hence, the liners and their design parameters are primarily studied to see its effect on SAG mill operations. Effective liner designs are directed to reduce downtimes, which is needed for the replacement of worn liners. There exists constant chance of improvement in the capacity of mill by studying the effect of liner design on the charge motion inside the mill. This need is satisfied by three-dimensional discrete element code "Millsoft", which uses Discrete Element Method (DEM) to analyze the motion of charge. This simulation of SAG mill keeps track of all the moving bodies like ball and rock and observes its interaction with liners and lifters. The recent work done on this software helps generating mill to more reality by putting conical wall at feed and discharge end, over the earlier flat walls. Millsoft is an effective tool to watch the change in the motion of the charge due to different types of lifter bars and different design parameters. It was concluded that by simply increasing chord length between the lifters and increasing the face angle of the lifters, capacity of the mill could be increased. On the other hand, this software can also be used to get power draft at the respective mill design.

Jan 1, 2002

By M. Alley, P. Schroeder, L. Zelazny, S. Nagle

The Old Hickory mineral sands ore body in Virginia (>2000 ha) currently supports a productive rowcrop agriculture. Reclamation experiments were implemented on pilot-scale mining pits from 1995 to 1998. Half of each mining pit was topsoiled (25 cm) while the remaining half was left as either (1) mixed tails/slimes or (2) re-graded subsoil over tails/slimes treated with 112 Mg/ha yardwaste compost. Post-mining productivity was estimated to be reduced by 23%, 3%, 27%, and 20% for each crop (wheat/soybeans/corn/ cotton) in sequence when compared to undisturbed soils. Variability in surface texture and compaction limit restoration of soil productivity.

Jan 1, 2002

By H. E. M. N. Moursy, Hassan El-Shall, M. N. Ahmad, Ponisseril Somasundaran, C. R. Holland, D. Chandler, G. Walker, Regis Stana, Patrick Zhang

The reaction kinetics of the acidulation of Moroccan phosphate rock (32% P?05) using 45% nitric acid were investigated using the Shrinking Core Model (SCM) , a newly developed Diffusion Model (DM) and a newly developed Combined Reaction and Diffusion Model (CRDM). This was achieved buy conducting a number of experiments in a controlled batch reactor system at different temperatures. The conversion and the reaction rate were calculated at different time intervals. The SCM based on reaction time and the CRDM characterize the acidulation process of phosphate rock. Diffusion of nitric acid and the products of acidulation at the early stages of reaction through the phosphate rock were found to be the rate-controlling step, resulting in a dif- fusion coefficient, which controls the mass transfer process. The reaction kinetics were found to fit first-order kinetics especially during early stages of reaction time. The deviation of the kinetics from first-order at later stages was due to the fact that the overall reaction was mass transfer controlled with respect to nitric acid and products diffusion.

Jan 1, 2002

By Ken A. Pfaff, Ray Daigh

This paper will discuss state-of-the-art applications of GPS automation in mobile conveying systems. Robotic mobile conveying systems increase profitability, optimize stacking and reclaiming operations, and control complex interfaces more accurately than other systems. We will also discuss the application process in machine-to-machine coordination, selection of the appropriate GPS system, and Ethernet considerations. As the leading supplier of GPS-controlled mobile conveying systems, we'll draw on our experience at Morenci, Radomiro Tomic, Zaldivar, El Abra (Figure 1), and El Tesoro mines in the US and South America to demonstrate system reliability and the lessons we've learned through analysis of these projects.

Jan 1, 2002

By James J. Graham

Uravan, Ambrosia Lake, Gas Hills and South Texas are all historic names in US uranium. These mining areas supplied the uranium that brought the United States into the nuclear age during the 1960s, and fueled the birth of nuclear energy for peaceful uses — a promise of nearly limitless, clean energy for the world’s future. That promise still exists today, but it is hard to hear over the rhetoric of environmental activists and politicians. Nuclear power offers dependable electricity with limited environmental impact at stable prices. Nuclear power releases no greenhouse gases or particulate matter into the atmosphere. High level nuclear waste (HLW), although long lived, is readily controlled and compact. In the United States, generating 1 billion kWh of electricity with coal produces 47 kt (52,000 st) of solid waste (ash and sludge), compared to 3.6 t (4 st) of HLW produced by nuclear.

Jan 1, 2002