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

Jan 1, 2005

By C Agreda

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

Jan 1, 2005

By J. Jankovic

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

Jan 1, 2005

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

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

Jan 1, 2005

By M. J. Gagnon

The agglomeration of particulate materials is used in many mineral processes to enhance the settling of the fine particles, Depending upon many physical and chemical parameters, the aggregates demonstrate specific density-size distributions, In this study, a fractal model of the agglomeration process is introduced, Based on reliable experimental data and on physical calculation, the model presented helps to envisage the initial formation of the micro-flocs, and to interpret the subsequent interactions between the aggregates in terms of either coagulation or flocculation, Data from different sources, materials and different agglomeration processes are analysed and compared in the light of the proposed model.

Jan 1, 2005

By Hee-suk Yun, Dae-jin Hwang, Jeong-woo Seok, Myoung-mo Kim

"In this paper, the accuracy of the data measured by a newly developed displacement measuring system, DPRMs (Digital Pile Penetration and Rebound Monitoring system) and its applicability as a quality control tool were verified by field measurements of pile penetration and rebound for pile driving performed at 3 construction sites and 1 test site. The DPRMs data were found to be much better than handwork data. A new dynamic formula for pile capacities is proposed uses the results of a pilot dynamic load test and the final pile penetration. The ratios of pile capacities obtained by the new formula to those by the dynamic load test were 94%±7.4% in the contrast with 123±28.3% by the 5S formula and 68±24.0% by Hiley's formula. This result shows the superiority of the new formula. The ratios of the maximum compressive stresses calculated by using DPRMs to those calculated by using PDA (Pile Driving Analyzer) were about 90-110±10%. This result confirms the applicability of DPRMs as an overdriving monitoring tool. Two sets of DPRMs were used to measure the 3-D displacement behavior of a pile head at the test site. The more the pile head moves laterally, the less the final set values were expected because of the loss of driving energy, but this trend was not obvious within the limited data obtained at the test site.INTRODUCTIONPile construction monitoring consists of two parts. In the first part, enough capacity of the pile is secured to stand the design load. In the other part, pile damage during driving is prevented. Although several methods can be applied to achieve the first part, PDA is nearly the only tool for measuring pile stress.Several methods such as a static load test, a dynamic load test, an Osterberg cell, and numerous driving equations can determine the pile capacity. Among them, the static load test and the dynamic load test are most widely used. The static load test is advantageous because it has the highest reliability. The disadvantages are as follows: it is costly and time-consuming. Also, the capacity of the pile under construction cannot be evaluated. The dynamic load test has lower reliability than the static load test, but it is cheaper than the static load test, is reliable enough to determine the pile capacity, can evaluate the capacity of a pile during construction, and can offer information about construction conditions such as the pile integrity and the pi le stress during driving. The dynamic load test takes a relatively short time and is low cost compared with the static load test. However, it is still costly, time-consuming, and unnecessary to apply to all piles in the field as a construction measurement tool. Therefore, driving resistance (blowcounts) is commonly measured to confirm the pile capacity at construction sites."

Jan 1, 2005

Sishen uses a state-of-the-art tracking system to track material from its position in blast blocks through various stockpiles and crushers. Qualities are blended directly to the crusher as opposed to blending from stockpiles. This poses an interesting challenge to the planning department to simulate these conditions. The software used in these simulations are Whittle 4X and Maximiser for long-term planning, Xpac for medium-term planning and Mine Works Planner for short-term planning. Geological models and mine design layouts utilise Surpac. Sishen introduced Xpac a number of years ago; the system has developed and changed over the years. With the Sishen Expansion Project (SEP), which aims to utilise low-grade material, major changes to the planning process have to occur. SEP requires that the mine have two different plants, which utilise two different ROM feeds and have different beneficiation curves. Xpac is used to produce a rolling 18-month plan, which is as close to actual operations as possible. In order to do this, the simulations have to take into account the plants beneficiation curves, stockpile movements, hauling distance and equipment needs. On top of this, the schedule has to continually consider specifications for Fe and the contaminants. Plant yields also have to be kept within a certain bandwidth. Xpac is used to simulate the above parameters, as well as generate the raw data required to produce a mine budget. The paper will also show how the 18-month planning process and subsequent planning processes are measured and aligned. Xpac has proved to be an excellent tool to achieve these goals.

Jan 1, 2005

Following the Moura No 2 Wardens Court of Inquiry and subsequent changes to the Queensland Mining Legislation there is a requirement in Queensland coal mines for: a person with the recognised competencies to be appointed at each underground coal mine to the position Ventilation Officer; and the person is directly responsible for the implementation of the mine ventilation system and for the establishment of effective standards of ventilation for the mine. The Regulations require that an underground mine must have principal hazard management plans that provide for at the least the following: emergency response, gas management, methane drainage, mine ventilation, spontaneous combustion, and strata control. Other than strata control all the plans require the ventilation officer to have roles and responsibilities to develop, control, monitor and undertake actions in relation to these plans.There are also another 34 Regulations that either directly or indirectly requires the Ventilation Officer to take actions.The purpose of this paper is to outline the information that the regulators look for in sealing plans and the actions the regulators will take if the sealing does not go to plan (TARPs being exceeded).

Jan 1, 2005

This paper outlines the role of commissioning in the project cycle, shows how to get organised for commissioning and describes the principal commissioning activities. Emphasis is placed on appointing key commissioning staff early in the project to coordinate the preparations for commissioning and on detailed planning and tracking to ensure that the required commissioning activities are performed satisfactorily. The management of safety during commissioning is reviewed.

Jan 1, 2005

By D McInnes

Rather than look at the problems associated with sampling, this paper deals with the issue of sampling and blending to optimise revenue û predominantly in the mining industry. An example of the use of this methodology in the agriculture industry is also presented. Mining companies, in particular, are experiencing a boom in commodity prices and many believe the industry is in the middle of a æsuper cycleÆ. Production levels are being escalated dramatically to meet the demand coming from China and India. This in turn has further stretched the capacity of our rail and port infrastructure û resulting in significant shipping queues around most Australian commercial ports and increased demurrage costs for the producers. Mining companies are now looking for effective scheduling, planning and blending to maximise production and reduce demurrage charges û given the current infrastructure constraints. Mining companies can no longer use spreadsheets to run their business. This paper further looks at how these outcomes can be met by optimised blending using an integrated supply chain management system such as MineTrak together with effective sampling and analysis.

Jan 1, 2005

By R Moreby

This paper is a demonstration of the techniques developed during an Australian Coal Association Research Program (ACARP) funded research project aimed to develop aids, principally computer based, to assist mine personnel to more efficiently manage significant incidents in coal mines. These aids include software to aid in the location of the incident, electronic information storage and retrieval, online site emergency response manuals and software to aid in decision-making.

Jan 1, 2005

By Ivan Weber

Asking the question, “What do the world’s leading corporations and cutting-edge practitioners of sustainability put forth to guide a given mine site for planning and action toward ‘sustainability’?”, this paper explores the spectrum of methodologies and mindsets in available literature, then constructs an example for the large near-closure facility at Kennecott Utah Copper. Values, opportunities and constraints spring from physical, unutilized byproducts, from critical ecosystems and wildlife populations, from location relative to those ecosystems and proximate communities, and from the political will to perform adequate feasibility investigations. Patience, determination and thoroughness are imperative. Identifying most productive and, simultaneously, most protective and restorative, practical methods to approach ‘sustainability’ has become a central mission of industry and business, worldwide. A survey of recent international initiatives finds no single approach that establishes either a readily adaptable methodology or an appropriate set of ‘attention’ points, or agenda, to guide individual mining operations at specific locations toward the elusive but essential goal of ‘sustainable’ mining. Untying this convoluted knot of contending factors requires willingness to recognize and work within ecological constraints for community long-term needs. Occasionally, the task requires the sword of Alexander the Great. Through integration that is unflinchingly honest ethically, culturally, economically, ecologically and scientifically, fully cognizant of place and community at whatever scales are of greatest significance, and integrative of both problem-response and opportunity, we may envision a mineral extraction and beneficiation future that achieves the best, most nearly sustainable, results possible. Industrial ecology (IE), with its clear emphasis on community, ecosystems, and sustainable economic stimulation, presents a sufficiently broad and adaptable discipline to facilitate planning and management toward sustainable mining. The creation of sustainable jobs encapsulates IE’s analogy to the niche survival strategies of organisms in nature. Open to common-sense recognition of faults and opportunities at appropriate scales, IE is less a discipline or prescribed methodology than a mindset, willing to be rigorously scientific when science is imperative, but also willing to exercise “art” when creativity or community engagement are needed. IE is also capable of future-looking compassion for peoples and nature. Looking beyond what has occurred to date, the case of Kennecott Utah Copper provides ample illustration of possibilities for community economic development, environmental management, and significant initiatives beneficial at regional and planetary scales, to become recognizable as deserving of the label, ‘sustainable.’ Through what this researcher terms “whole mine, whole region, whole planet” thinking, strategies become visible and subject to serious consideration, presenting a path to best possible accomplishment in mining. Constituting a maximal broadening of mining’s “traditional” scope, the integrative approach proposed here is the ‘paradigm shift’ being made by many other industries around the world. In aggregate, these steps are the only hope for avoidance of environmental, social and economic risks that threaten to curtail resource development and impair mining companies’ ‘social license to operate.’

Jan 1, 2005

By P J. Ellen

The selection of the ore haulage system is a key decision made in the development of an underground mine. The haulage system is one of the components that define a mineÆs ability to respond to changes in mining inventory and market conditions. The complexity of this decision for Telfer Deeps was affected by the realisation during the feasibility process that the true scale of the potential underground mineralisation at Telfer was still to be quantified. This paper provides an overview of the process used in the Telfer Project Feasibility Study to select an ore haulage system for Telfer Deeps. The purpose is to highlight the value of impartially approaching tasks of this type with a robust process. The process should be able to respond to issues identified as the task progresses towards the objective of finding the best solution for an ore haulage system for the mine. For Telfer Deeps, this process resulted in the selection of a haulage system built around a shaft. The systems considered during the feasibility are discussed and the components of the haulage system constructed for Telfer Deeps are described.

Jan 1, 2005

By L. M. Oshinowo

The incorporation of advanced analysis tools, such as CFD, into the process plant design process has become possible through advances in commercially available computational fluid dynamics software and faster computers. Multiphase modeling is now typically employed in the design phase of process plant design at Hatch. The multiphase models include Lagrange-Euler and Euler-Euler treatment of the multiple phases. Additionally, mixture models with interface-sharpening algorithms are applied to the prediction of free-surface flows in complex geometry. CFD is applied to applications where traditional design rules are not applicable. The additional rigor of CFD modeling in 2D and 3D allows process engineers to come closer to realizing true virtual plant design. The objective of this paper is to outline the benefits and pitfalls in the application of multiphase modeling for rigorous design. Several application examples in the hydrometallurgical field will be presented.

Jan 1, 2005

By Charles M. Wilk

"Solidification/stabilization (S/S) treatment is used to treat hazardous wastes for disposal and in the remediation/site restoration of contaminated land . SIS is also an increasingly popular technology for Brownfield (industrial property) redevelopment, since treated wastes can often be left on-site and to improve the soil for subsequent construction. This paper discusses the applicability of the technology to various wastes, basic cement chemistry relating to SIS, tests used to design treatability studies and to verify treatment, basics on implementation of the technology in the field , and examples of SIS use at brownfield sites, including a former wood preserving site, former manufactured gas plant sites, a former electric generating station, and a shopping mall development.INTRODUCTIONSolidification/Stabilization (S/S) is a widely used treatment for the management/disposal of a broad range of contaminated media and wastes; particularly those contaminated with substances classified as hazardous in the United States. The treatment involves mixing a binding reagent into the contaminated media or waste. The treatment protects human health and the environment by immobilizing contaminants within the treated material. Immobilization within the treated material prevents migration of the contaminants to human, animal and plant receptors. SIS treatment has been used to treat radioactive wastes since the 1950s and hazardous waste since the 1970's (Conner 1990). SIS continues as a cornerstone treatment technology for the management of radioactive waste, hazardous waste, and site remediation and Brownfield redevelopment."

Jan 1, 2005

By Antonio Peralta, Guillermo Dante Ramírez-Rodríguez

Mining is generally considered a large-scale hightech industry. However, it has estimated that about 12 million people, about 30% of the world’s total mining workforce, relied on small-scale mining for their livelihoods. During the years, the large-scale mining industry has developed best practice environmental procedures, which have been applied in diverse settings through the world. In contrast, small-scale mining is better known for its high environmental impact and the lack of safe and healthy working conditions. This paper will discuss the environmental control strategies used by the large-scale mining industry, and its applicability to small-scale mining in developing countries.

Jan 1, 2005

By M. Greyling, C. Panaou, M. Bellino

Commonly the most frequent method of calculating the overall mass balance of a multi mineral platinum-group metal (PGM) concentrator circuit in Southern Africa has been through the use of spreadsheets, typically Microsoft EXCEL®. While there are some advantages in using spreadsheet based mass balances during the conceptual design phase of the project, their use becomes limited in the detailed design phase of the project. This paper discusses the successful application of METSIM® for mass balancing of a PGM concentrator and highlights the benefits gained during the conceptual and design phase of the project.

Jan 1, 2005

The Health Tracking project is one of five projects being undertaken as part of the Minerals Industry Cooperation Initiative (MICI) û a national initiative sponsored by the Minerals Council of Australia. The aim of the Health Tracking project is to assess the practicality of ways to demonstrate the monitoring of hazardous exposures and the occurrence of related occupational illness and disease and development of management systems and strategies at a national level. This second stage of the project will be completed in 2005 and will cover four areas: pilot development of a comprehensive job exposure matrix (JEM) for the minerals industry; development of both proactive and reactive occupational illness and disease metrics; recommendations regarding appropriate health tracking models; and provision of best practices guidelines for management of occupational health. The synergies between these areas will establish the path towards an effective national occupational health surveillance system and the development of effective prevention strategies and policies.

Jan 1, 2005

This paper contends that optimisation of energy resources through active control and predictive simulation modelling is possible, and that such monitoring leads to large savings in the electricity costs of hot mines (where refrigeration has to be employed). In addition, active monitoring and control can positively affect the establishment of a safe, healthy and productive working environment. In the entire optimisation process certain guidelines were set to ensure that the requirements of the Mine Health and Safety Act were met (South Africa). Varying the quantity of air supplied underground by means of variable speed drive (VSD) fans is one of the crucial factors in the interactive approach towards the optimisation of ventilation, as is refrigeration and the pumping requirements associated with refrigeration. This article highlights the interaction between the amount of air supplied and the effect it has on refrigeration requirements underground. This article also considers the effect that this would have on contaminant control. Various tools are available for ventilation and cooling design for mining. A lot of these tools are based on the assumption of steady state conditions and do not take into account instantaneous changes in conditions, day-to-day, or hour-to-hour (such as for temperature and contaminants). They also do not take into account the optimisation of energy resources related to the creation of the acceptable underground conditions. With these tools worst-case and best-case scenarios are identified, and strategic decisions are made accordingly. Currently, the amount of the fresh air, the velocity of the air, and its general temperature in the mine are only changed when one production phase changes into another (or when unacceptable conditions occur as a result of poor design or neglect). This means that during a specific production phase (which can last for several months), there can be an oversupply, or undersupply, of energy resources, which will obviously affect the concentration levels of the various contaminants (through under or oversupply of air).

Jan 1, 2005

By L. Kilburn

"A survey of 281 mineral exploration agreements examines the ratios among three ways that may be used to purchase an interest in a mineral property, viz: pay cash, pay shares and make future expenditures on the property.The dollar value of the future expenditures exceeds that of cash or shares by about nine times in most of the 110 agreements that contain cash-expenditure or share-expenditure components. Results suggest that cash and shares are treated about the same in terms of value.Buyers and sellers have opposing priorities for the way that they prefer to purchase a mineral property. These opposing priorities should give rise to a perceived 50:50 balance between cash/share payment and future expenditures to satisfy the idealized situation described by most definitions of fair market value (FMV). This balance between cash/share payments and future expenditures appears to be rationalized in negotiations to a FMV when expenditures are nine times greater than cash and/or payments.On this basis, it is proposed that the FMV of a property may be determined by aggregating the dollar amount of the cash/share payments plus one-ninth the dollar value of future expenditures, as set forth in the respective purchase agreement, and proportionately applying such aggregate to full property value."

Jan 1, 2005