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In an industry that is data-hungry and increasingly international in its outlook, the role of the New Zealand Government in facilitating exploration and mining activity here presents unique challenges. All things being equal, the Regime itself should result in æefficient outcomesÆ, however central to this rational economic tenet are the assumptions that the regime is in keeping with the times, other legislation works in tandem with it, and that those who administer the regime have the knowledge and experience to apply the rules wisely. Following the Crown Minerals review in late 2003, a shift in emphasis from Crown Minerals æmanaging the ActÆ towards proactively æmanaging the mineral estateÆ for greater benefit for all New Zealanders means that these assumptions are being increasingly challenged and addressed through a variety of initiatives. These include improved access to relevant data sets, minimisation of red tape and compliance costs, increasing emphasis on permit holder compliance with work programme obligations, changes to the Minerals Programme and regulations, closer collaboration with and representation to other government departments and councils, and additional recruitment of industry-experienced staff. This presentation will highlight aspects of these initiatives, and examine how they will collectively contribute to facilitating future exploration and mining activity in New Zealand.

Jan 1, 2004

By David S. Shatzer, Michael R. Purcell

Current world events have demonstrated the use of commercial vehicles, other unconventional modes of transportation and unusual materials as explosives or incendiary weapons, affecting commerce, disrupting cities and even entire societies. Since the implementation of the Organized Crime Control act of 1970 the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has been investigating and studying explosives and incendiary devices and their related effects.

Jan 1, 2004

By M. M. D. S. Vemba

Paper written on project work carried out in partial fulfilment of B.Sc. Eng (Mining Engineering) degree Engineering refers to the application of mathematics and other sciences to logically develop solutions to problems. However, in opencast mining, due to the randomness of operations, the use of mathematics is often neglected. Instead, practices that have proven successful elsewhere tend to apply. At the other end of the scale, mathematical models have been developed to identify and quantify all the operational parameters involved in the loading and haulage of ore. These are then used to optimize the operation. Optimization in this context, refers to the reduction of cost through effective utilization of the available time and resources. Considering these mathematical models, the loading and transport system at SMC (Catoca Mining Society) will be assessed with a view to its optimization. The discussion will be introduced by considering the mine background and other general information, which will highlight the main operational variables.

Jan 1, 2004

By W. Barthel, B. A. Dippenaar, J. Malan

In its most basic form, the process of sintering is very simple, and has been in use since the turn of the previous century. However, while the basic process is simple, control of the process relies on a number of extremely complex interdependent process parameters and requires a thorough understanding of the effect of these parameters on production capacity and product quality. Further, as with many other processes, the process parameters and hence design details of visually similar installations are highly dependant on the specific feed materials. While the industry trend has been towards an increase of capacity in order to lower unit production cost, typically in Iron ore sintering plants, this approach is not always possible for other commodities because of the scale of operation. This paper seeks firstly to describe some design considerations of sinter plants; secondly, to report on results from testwork performed with a specific series Manganese ore blends; and last, to relate these results to the design of new small-scale Manganese ore sinter plants.

Jan 1, 2004

[Dr. N.A. Barcza (Chairman) Mr. R.J. Linnell (Vice Chairman) Mr. J. Basson Dr. L.A. Cramer Mr. W.A. Gericke Dr. N.C. Machingawuta Mr. C.S. Mahony Dr. L.R. Nelson Mr. D. St J. Slater Mr. B.J. van der Walt INFACON X TECHNICAL PROGRAMME COMMITTEE Dr. L.R. Nelson (Chairman) Mr. W.A. Gericke (Vice Chairman) Mr. W. Barrett Mr. T.R. Curr Dr. O.F.R.A. Damm Prof. R.H. Eric Mr A.M. Hearn Mr. A.R. Jamieson Dr. N.C. Machingawuta Mrs. L. Mthombeni Mr. F.X. Prins Mr. J. van Tonder ]

Jan 1, 2004

By E. M. Timoshenko, A. V. Tarasov

The results of laboratory, bench-scale and semi-commercial investigations of a method for adding surfactant (technical-grade lignosulphonate) to the process of pressure leaching of nickel-containing pyrrhotite concentrates have been discussed. Lt has been demonstrated that feeding of technical-grade lignosulphonate distributed along the length of an autoclave ensures a reduction in its requirement by a factor of 1.5 to 2 as compared with single-point feeding; it also results in a decrease by 5% in the unit requirement of metallized iron-bearing precipitator in the process of non-ferrous metals precipitation and reduces by 0.05 to 0.1% (abs.) the nickel and copper contents in the tailings of the given process. Technical solutions have been proposed for commercial introduction of the process.

Jan 1, 2004

By Dennis Nottingham

Increased interest in seismic soil liquefaction and preventative soil stabilization sets the stage for improved deep compaction methods using pile driving techniques. In 1971 L.B. Foster Company personnel patented a method of deep compaction using a vibratory pile hammer and pile probe. The technique had some success, but did not produce consistent results and thus found its way to obscurity. Other patents attempted to modify the technique by various probe modifications, but again without measurable improvement from a practical point of view. Solutions to economical deep compaction up to 100-foot depths particularly in saturated granular soils would have a great impact on the construction industry and new bulkhead structures being developed, thus PND was prompted into related research and development. The advent of higher horsepower vibratory hammers, coupled with PND engineers' experiments, observations and measurements, led to an "H" pile probe design which has produced measured soil density improvements up to 250% using SPT "N60" values as a measure. Case histories of two projects involving extensive SPT soil sampling comparative measurements will be discussed along with findings that led to the compaction success. Applications to numerous modern "Open Cell" bulkhead projects will be presented and discussed.

Jan 1, 2004

By Hassan El-Shall, Ayman El-Midany, Patrick Zhang

Bench and pilot scale testing results suggest that significant improvement in dewatering characteristics of fine particles could be obtained by the addition of fibrous materials. Case studies involving flocculation and dewatering of wastes from phosphate, bauxite, and kaolin processing plants are presented in this paper. Several dewatering techniques were investigated, including sedimentation thickening, filtration, centrifugation, dewatering on screens, and seepage-induced dewatering and consolidation. Advantages and limitations of commercial application of some of the developed techniques arc discussed.

Jan 1, 2004

By V. Dezelic, D. B. Apel

This paper describes the results of laboratory and field experiments conducted to determine the applicability of Ground Penetrating Radar (GPR) for the assessment of the strata thickness and for the identification of separation between bedding planes in stratified rocks. The knowledge about the extent of such separation in the roof layers and information about roof lithology can be used to determine the roof support requirements for underground mines where stratified rocks are present. The laboratory and field experiments were conducted at the Rock Mechanics Laboratory and the Experimental Mine at the University of Missouri-Rolla. The 1.5 GHz high resolution, shallow depth GPR antenna was used for all of the experiments.

Jan 1, 2004

By M Reza Afshar

In this work a mathematical model was developed to study the effect of electromagnetic force on the magnesium melt containing nonmetallic inclusion in an electrical isolated channel. The electromagnetic force exerted on the inclusion induced by DC current field was calculated. A three dimensional turbulent flow equations were solved numerically to compute the velocity field within the channel. On the basis of computed velocity and magnetic fields, the trajectories of inclusions were calculated using the equations of motion for inclusions. Parametric studies were carried out to evaluate the effect of various parameters such as current density, channel diameter and particle density on the removal efficiency of inclusions from magnesium melts.

Jan 1, 2004

By Crazy Horse - The Journal of Explosives Engineering - Vol 20 No 1

The crew at Crazy Horse Memorial has produced a w o n d e rful new video called “The Fine Art of Mountain Carving.” The video closely examines for the first time, the extraordinary explosives engineering on the Crazy Horse mountain currently in pro g ress in the Black Hills of South Dakota. The 56-minute video takes the viewer up the mountain for a behind-the-scenes look at the drilling and blasting crew at work on the mountain. The video was written, edited and produced by Robb D e Wall and is available exclusively from the Crazy Horse Memorial in both DVD and VHS formats. For i n f o rmation, see www.crazyhorsememorial.org The following, is a brief summary of the 25 steps involved in carving the mountain. The video goes into extensive detail on each of the 25 steps. Both those in the explosives industry and those outside the industry will find the video intere s t i n g .

Jan 1, 2004

By Sam Kangwa, Thomson Sinkala

Th e re are three basic types of hole deviations in long hole d ri l l i n g , n a m e l y collar i n g , alignment and tr a j e c t o r y dev i a t i o n s . In mining, the accur a cy in drilling has a significant effect on the effi c a c y and economy of mining oper a t i o n s . This ar t i cl e d e s c ribes the types, s o u r ces and effects of hole deviations in mining oper a t i o n s . The art i cle further demonstrates the economic consequences due to hole dev i a t i o n s .

Jan 1, 2004

By M. Reuter, U. Boin

The target of the current metallurgical industry is to recycle and utilize all their by-products, so as to close the sustainable production loop. Slags are the important wastes and by-products of metallurgical industry, which have been treated, recycled and used worldwide. The present paper summarizes the current status of utilization of the various slags from ferrous and non-ferrous metal production, as well as waste incineration, and recycling of salt fluxes in secondary metal production. In addition, the environmental issues of the metallurgical slags are addressed. The metallurgical oxide slags have stone-like properties and, thus, their major applications are in civil engineering field. The slags should be recycled, modified and processed in a proper way, by taking the environmental impact into consideration. With the treatment of salt slags for melting aluminium scraps, as an example, the recycling and elution properties of the salt slags are discussed. Our research indicates that the viscosity of the salt flux is increased with addition of non-metallic components, that a certain percentage of fines remain in suspension, which determines the viscosity, affecting the settling of heavier materials. High slag viscosity will lead to more fine aluminium metal entrapped in the salt slag (may also be seen as a high temperature slurry), and thus increase the load of salt slag recycling. Keywords: recycling, environment, metallurgy, slags, fluxes, salts.

Jan 1, 2004

By William R. Yernberg

What a difference a year makes. One year ago, the iron mining industry and the steelmaking industry in the United States were in trouble. Many companies were in bankruptcy, and talk of plant and mine shutdowns was rampant. At that time, it seemed difficult, if not impossible, to remain competitive with imported steel. In addition, the World Trade Organization declared as illegal the tariffs placed on imported steel. And many questioned the viability of the ironmining and steel industry in the United States. At that time, global economic conditions were the main contributors to the industry’s problems. However, since last year’s meeting, changes in global economics have actually helped the steel industry in the United States. Heavy global demand for steel has caused raw-material shortages worldwide. Much of the increased demand is a result of the economic boom in China. In addition, because of a weak U.S. dollar and higher international freight rates, steel imports into the United States have been reduced to about 50 percent of recent levels. These factors have contributed to a rebirth of the U.S. iron mining and steel industries.

Jan 1, 2004

By E. Ferguson

In evaluating refractory designs for cast house applications, thermal calculations are frequently performed to determine cold face shell temperatures, temperature profiles and metal freeze plane locations within the refractory layer, and heat loss in the steady state condition. A problem arises when looking at molten metal transport crucible designs in that these structures are usually operating under non-steady state conditions throughout their production cycle. Because the molten metal temperature varies with time, and material properties such as thermal conductivity are temperature dependant, mathematical solutions are at best... complicated. This paper presents a relatively simple, iterative solution, that can be set up on a standard computer spreadsheet program, to calculate heat transfer in non-steady state conditions. These calculations can provide curves for (1) molten metal temperature vs time and (2) cumulative heat loss vs time, given variable starting conditions, to aid in the evaluation of molten metal transfer crucible refractory designs.

Jan 1, 2004

By J. Basson, L. R. Nelson, L. A. Cramer

The South African based platinum mines produce the world?s majority of platinum metal that is used in autocatalysts and jewellery. As the platinum market is forecast to grow at healthy rates into the future, the South African producers, Anglo Platinum, Impala, Lonmin and Northam are planning to expand in the next decade. Furthermore a number of smaller producers who are accessing other mineral rights are entering the buoyant market. The South African platinum mines have traditionally exploited the Merensky reef of the Bushveld Igneous Complex (BIC); however, the mining of this reef is reaching depths that require significant vertical shaft systems and costly refrigeration for access to the ore bodies at deeper levels. In the past decade all of the producers have begun to mine the less attractive UG2 reef because of its cheaper mining costs. This UG2 reef contains significant quantities of chromite with typically a chrome-to-iron (Cr/Fe) ratio of 1.35. UG2 ores can contain between 10 and 25% Cr2O3 depending upon the reef width and the selected mining method. It is relatively cheap and easy to extract a portion of the chromite from a platinum concentrator tailings stream at a grade of between 40-42% Cr2O3. However it is only in recent years that some ferrochrome producers have begun to source some of their chromite from the tailings of platinum producers. South Africa is also the world?s largest single producer of ferrochrome and supplies much of the world?s stainless steel producers and thus the growing market for their product. As the traditional sources of high Cr/Fe ratio ores have been depleted at the shallow economic depths and thus have become more expensive sources of chromite, technical developments have improved the ability to use fine chromite economically to make acceptable grades of ferrochrome. Thus UG2 fines are now becoming possible cheap sources of acceptable feed to the ferrochrome industry. The abundance of feedstock for ferrochrome production and the lessening dependence on mined material will impact upon the structure of the ferrochrome business in South Africa. With continued platinum mining from UG2 reefs, South Africa is set to remain highly competitive in the world?s ferrochrome/stainless steel industry.

Jan 1, 2004

By B. Dabrowski, J. D. Miller, D. Halbe, J. Hupka

An air-sparged hydrocyclone (ASH) mobile system was evaluated for continuous stripping and recovery of cyanide (the AVR process) from process water at a gold plant site. The ASH unit performed exceptionally well as an absorber. HCN was removed from the gas phase in a single one second pass with an efficiency exceeding 99%. HCN concentration in the discharged gas phase was lower than 10 ppm, which provided for a safe working environment. The stripping efficiency, controlled by the Henry’s Law constant, exceeded 40% in one pass.

Jan 1, 2004

By D. Reddish

The combination of free standing steel supports, such as arches, and rock bolts (mixed support) has Frequently been in used in UK coal mine roadways when it is considered that the strata and/or environmental conditions would not be suitable for rock bolts solely. However, how such mixed support systems operate is not fully understood. Due to the differences in the support method provided by rock bolts and free standing steel, the total support generated is not simply a case of adding the contribution to the support of the roadway given by the two systems. This paper describes a numerical investigation into mixed support systems when used in coal mine roadways. A series of 2D and 3D geomechanical models are described and the method of modelling the rock bolts and steel supports in coal mine tunnels is discussed. The numerical models described include rock boltd only roadways, steel supported roadways and mixed supported roadways in a variety of geological and in-situ stress conditions. Conclusions are formed that allow an insight into mechanisms of strata reinforcement provided by the support systems modelled. Further to this, a review of the numerical modelling of pre-tensioned rock bolted systems is described identifying the contribution to support efficiency given by the adoption of tensioning in full column resin anchors. The results obtained highlight that the effectiveness of the pre-tensioned load is dependant on the rock mass quality and in- situ stress level at the site where it is to be used.

Jan 1, 2004

By Steve Crewdson

High tonnage hoisting of materials by vertical conveyors through deep shafts is a relatively new concept in mining that is proving to be effective. The development of the Pocketlift® belt by Metso Flexowell, located in Moers, Germany, enabled the installation of a deep shaft vertical conveyor in 2002. This application followed years of design and operational experience gained in medium-depth shafts around the world. The design, manufacture, installation and operational experience of an 1,818 tonnes capacity, 273 meters vertical lift, Pocketlift® belt system at the White County Coal Pattiki 2 Mine is the subject of this work

Jan 1, 2004

By Osvaldo A. Bascur, J. Pat Kennedy

Large metallurgical complexes have more data than a small city and much of it is "real time," changing rapidly as internal and external conditions evolve. As corporations buy and sell assets and reengineer their staff, the structures and tools that were used to understand these data are lost. The lack of an integrated approach makes the profitability of metallurgical plants lag behind that of other industries despite technical advances that have occurred in recent years. This results in significant deterioration in the ability to maintain a "smart” operation. The solution is to use the sophisticated new tools built for the Internet so as to leverage information in a familiar browser format that people can use and understand. Combining real-time infrastructure with portal technology is becoming an accepted methodology. This paper introduces real-time portals and team sites to support decision making by work- groups which require both real-time and documentary information from manufacturing assets, vendors, head office and the Internet. Workers get insight from the overall process effectiveness index based on key variables such as losses due to plant availability, performance efficiency and rate of quality. Real-time portals and smart clients are part of any real-time performance management (RtPM) solution. Three case studies in large metallurgical complexes are presented. PLANTS ARE YOUR STRATEGIC HANDICAP Information technology is arguably one of the fastest moving technologies used by the mining/metallurgical industry. However, the business model for managing that

Jan 1, 2004