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This paper examines the concepts of risk analysis and uncertainty in open pit mine design. It describes the relationship between risk analysis and uncertainty, describes methods that can be used to quantify uncertainty, and suggests ways of reducing the geological and geotechnical uncertainties that are inherent in open pit mining.

Jan 1, 1994

By Coskun B

The classification of selective mining units (SMU's) and the assignment of grades to those classified SMU's are very important in open pit mining, especially for precious metal mining. During ore control planning, the classification of mineral

Jan 1, 1998

Topography, location of coal bearing land and existing built-up areas severely restrict locations for overburden disposal and dumping sites north of the Latrobe River clear of the coalfields are assumed until internal dumping areas can be established.

Jan 1, 1982

The high maintenance of load-haul-dumps (LHDs) and front end loaders in hard rock affects mine planning with reduced availability and productivity. Intensive study of maintenance costs and availability of machines related to machine age and life provide the basis for planning from available operational alternatives.Derived programmes and experiences have led to the beginnings of unmanned operation and automation through reduction of manual diesel units and spreading electrification and use of radio. But electrification has obvious layout limitations. This approach to the present has resulted in better utilisation, costs and safety and the computerised monitoring and control provides continuous awareness of machine and work conditions with the promise of future improvements.

Jan 1, 1991

HISTORY Up until the late 1880's the mining industry acquired a considerable proportion of its capital needs from domestic sources. Exchanges were established wherever major new fields were opened and Ballarat, Bendigo, Charters Towers, Coolgardie, Kalgoorlie and Silverton all boasted active trading in mining shares. For much of the first half of this century there was only modest developments in the mining industry and its capital require- ments were correspondingly lower. RECENT EXPERIENCE The new mines of the sixties were, in many cases, characterised by their remote situation and their output of bulk commodities such as iron ore., coal and bauxite. Infra- structure costs were particularly high and the level of capital expenditure was of previously unheard of proportions.

Jan 1, 1975

By Alvarez A. R, Garcia H. l

A fuzzy expert system, DIME, has been developed, under Matlab v 5.1. to assess the coal and gas outburst risk in underground mining. Expert systems and fuzzy logic are powerful tools to manage information represented by linguistic statements,

Jan 1, 1998

By Nguyen T. T, Williams A. M, Siauw T. H

During the last 20 years the CSIRO Division of Manufacturing Technology, through its research and development program, has made a substantial contribution towards understanding the pressure die casting process. Much of this work focused on the hot chamber die casting of zinc, where the importance of achieving optimum flow of metal into the die cavity, combined with the correct thermal balance of the tool, is critical to the production of high quality castings. Having developed a fuller understanding of the heat and fluid flow occurring in the pressure die casting process, CSIRO sought to make this information available to the industry in a form where it could be readily used by die casting engineers. This led to the development of DMT-CASTFLOW and DMT-CASTHERM, two unique, PC-based, die design software packages. DMT-CASTFLOW provides facilities for designing running and gating systems while DMT-CASTHERM enables the die designer to optimise the cooling and/or heating requirements of the die. These two packages are now being sold internationally. This paper will describe some of the major features and benefits that can be derived by using DMT-CASTFLOW and DMT-CASTHERM panicularly in the design of zinc pressure die casting dies.

Jan 1, 1993

By Jimbo I, Ogawa O

A series of experiments was carried out to investigate the solubilities of copper, arsenic, antimony and bismuth in silica-saturated iron silicate slags under controlled oxygen partial pressures at 1200 and 1250¦C. Molten copper containing each of the above elements was kept in contact with a slag in a silica crucible for 24 or 48 hours to attain equilibrium. No me- chanical entrapment of metal into the slag was observed. The appearance of the magnetite phase in the slag was avoided by holding oxygen potentials at substantially lower values than that evaluated from available data on iron silicate slags. Solubilities of copper, arsenic, antimony and bismuth in slags were plotted against oxy- gen potentials and both oxidic and atomic types of dissolution were found, except in the case of arsenic, from the dependencies of the solubili- ties on the oxygen potential and from positive intercepts of regression lines when extra- polated to zero oxygen potential. The dissolu- tion of arsenic seemed mostly oxidic. Distri- bution coefficients of arseò,ic, antimony and bismuth between copper and slag are also Discussed.

Jan 1, 1980

While reaction to immediate demands may be required from time to time, the principal concerns of a Geological 'Survey should be proaction, with respect to the systematic production of maps, reports and data in order to meet exploration needs in the longer term, and interaction, which involves a complex matrix of relationships - firstly within the Department between disciplines and at various levels of responsibility, secondly with the exploration industry, thirdly with Commonwealth authorities particularly the Bureau of Mineral Resources (BMR), and fourthly with university researchers in related fields.

Jan 1, 1987

The Australian Mineral Industry has to compete on world markets, so its mineral research has to be aware of overseas developments, it must be of world class, and it must utilise as many ideas as possible in order to solve those problems that uniquely affect Australian minerals processing. North American mineral and resource research may be taken as a guide to world government, industrial, contract, and entrepreneurial research trends and ideas. A number of interesting findings are noted that may guide Australian developments and strategies for the future, in minerals research and exploitation.

Jan 1, 1986

Diamond bearing deposits are extremely low grade and require large bulk samples to be tested to determine the grade and quality of the stones. The semi portable plants, for treatment of these bulk samples, have followed the development of commercial processes for diamond concentration. These processes included jigs and diamond pans, which have been largely supplanted by heavy media processes for primary concentration, due to the higher efficiencies in all size ranges. A number'of flowsheets including these processes are presented. The final recovery of diamonds from the bulk sample concentrates can be accomplished by rejigging, adherance to grease or by X-ray sorting. Flowsheets incorporating all the processes are presented. Two plants are described; one incorporating jigging, rejigging and hand sorting; the other using heavy media separation, and wet X-ray sorting.

Jan 1, 1984

By R G. Barker, A B. Christie

Minerals are necessary for providing almost everything we take for granted in our daily lives including food, shelter, and supplies of energy and water. Minerals are therefore essential for the maintenance and improvement of the standard of living of all New Zealanders.

Jan 1, 1998

Depending upon the probability one assigns to project go-ahead, up to $10 billion (1978 figures) could be required for resource based projects in Australia in the next decade. In the past major resource projects were readily financeable against sales contracts. In the future the complexities imposed by such matters as political risk, inflation, currency movements and environmental and other socio- economic considerations on project development costs and returns may require a different approach. This paper addresses itself to the ramifications of providing development finance for resource based projects in the future - and in particular examines such factors as project completion guarantees, sales contracts, protection against exchange rate fluctuations, interest rate structures and debt/equity ratios as each relates to the provision of finance. TABLE OF CONTENTS SECTION 1 : Introduction SECTION 2 Factors Affecting Project Financing in the Next Decade SECTION 3 Some Aspects of Financing New Projects in Australia in the 1980's Conclusion

Jan 1, 1979

By S Hapugoda, J Manuel, N Ware, A Dehghan-Manshadi

The effect of titania (TiO2 ) addition on the sintering performance of hematite iron ore has been studied by doping pure TiO2 into a sinter blend. The results of laboratory-scale compact sintering tests confirmed the considerable effect of TiO2 addition on sinter strength and mineralogy. The tumble index measurements confirmed an improvement in the strength of the sinter in response to TiO2 addition. The melting point of the sinter was also affected by increasing the TiO2 content, indicating a possible relationship between coke breeze consumption and TiO2 on industrial-scale sintering of Ti-bearing ores. Analysis of the sintered structures using optical and scanning electron microscopes confirmed a general improvement in the overall pore structure and sinter melt characteristics with the addition of TiO2 to the sinter blend. An important feature of the sinter structure was the formation of a perovskite phase (CaTiO3 ) and an increase in the proportion of this phase in the structure as TiO2 levels increase.CITATION:Dehghan-Manshadi, A, Manuel, J, Hapugoda, S, Ware, N and Donskoi, E, 2015. Effect of titania on the sintering performance of hematite iron ores, in Proceedings Iron Ore 2015, pp 29–34 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By A G. Dempster, B McKeown, S Saydam, J Coulton

The mining industry has undergone a profound and transformative shift in recent years, driven by the rapid advancement of emerging technologies such as automation, digitalisation, and electrification. These technological innovations have not only revolutionised operational efficiency and productivity but have also introduced an imperative need for new and innovative approaches to conducting mining activities. Specifically, the mines of the future face a new series of complex challenges when planning and developing greenfield or brownfield mining projects in the 21st century. These challenges include greater operational depths, higher seismicity levels, higher rock temperatures, increased environmental constraints and sustainability requirements, a higher degree of interoperability, lack of skilled workforce, and the need for sustainable and eco-friendly mining practices. Consequently, there is an essential need to formulate novel strategies and robust planning methodologies that re-evaluate how mines are planned, executed, and managed, from the early exploration stages to the post-mining era and the consequent uses of mine sites. This research focuses on identifying the factors influencing the implementation of modern technologies, such as autonomous machinery in mining operations, and their impact on mining method selection and longterm mine planning. The findings underscore a crucial need for a paradigm shift in how mines are planned and developed, going beyond mining method selection, which primarily focuses on geological and economic factors, and must evolve to incorporate the multifaceted implications of modern mining operations.

Sep 1, 2024

By Walker G. S

Infrared and Raman spectroscopy have been used to study a range of solid state and aqueous solution species which are of interest in extractive metallurgy. In the solid state new Cu(II)/CN'/NH3 complexes have been detected, iron impurities in kaolin characterised, aluminium substitution in hematite and goethite quantified, and the crystallinity and orientation of zircon determined in heterogeneous crystals. In aqueous solution metal cyanide complexes and equilibria were readily characterised, the thermal decomposition of SO2 monitored and products identified, and complexation of AI(III) by hydroxycarboxylates observed. Attempts to monitor the early stages of the gelling of silicate solutions were less successful, with only changes in the gel being detected. However, the degradation of 12-tungstosilicic acid was readily monitored as a function of both time and pH.

Jan 1, 1996

A new two-metre column self-heating test procedure has been developed at the University of Queensland, which clearly shows the hot spot development phases that take place in bulk coal self-heating. The column results provide a more reliable indication of the self-heating propensity of coal than small-scale index tests. At the same time, off-gas evolution patterns associated with hot spot development are obtained, including the recognition of hydrogen evolution from oxidation at temperatures less than 80¦C. Subtle differences in off-gas evolution from self-heating between gassy and gas-drained coal are also apparent. This new approach to coal self-heating assessment offers an opportunity to further the understanding of the complexities of spontaneous combustion and will enable more accurate risk assessment for the coal industry.

Jan 1, 2005

By M Lak, R Amiri, A Haratian, M Asghari, S Haji

In recent years, due to advances in designing of various magnet assemblies, a wide range of magnetic materials with different properties can be concentrated. Jalal Abad iron ore beneficiation plant, which is located in Iran, Kerman province, is currently producing iron ore concentrate with the capacity of 0.8 Mt/a by having medium intensity magnetic separators (MIMS) with rougher and cleaner stages that finally leads to the production of an iron concentrate with the Fe grade of about 65 per cent. In this plant, the rougher tailings directly goes to the thickener as the final tailings and cleaner tailings feeds to the ball mill for regrinding. Since some hematite particles with weak magnetic properties cannot be recovered from only these two stages of magnetic separation, the obtained tailings from this concentration plant has approximately an iron grade of 25 per cent to 27 per cent. Accordingly, laboratory processing tests were conducted on the obtained representative sample of the final tailings. Based on the experimental results performed on final tailings, a new magnetic drum separator with a specific magnetic assembly was designed that could finally lead to product with iron grade range of 58 per cent to 60 per cent with relative and total weight per cent of 8.6 per cent and 3.86 per cent. Finally, it could be concluded that feeding of magnetite particles to the existing drum separators, due to their high magnetic field intensity, cannot efficiently lead to improvement of the grade of concentrate. Therefore, pilot magnetic separation tests were done on the final concentrate for evaluation of product upgrading probability. Consequently, by increasing another stage of cleaning and by decreasing the magnetic field intensity, the final product grade could be enhanced from 65 per cent to 67 per cent.

Nov 8, 2021

By Smith N. S, Rholl S. A, Otterness R. E

The Bureau of Mines is conducting research to develop blast designs for the control of fragmentation and rock displacement and the reduction of overall mining costs. This Bureau experiment, a program of 25 reduced-scale blasts conducted at the University of Missouri-Rolla's experimental quarry, determined the effects on fragmentation of changes in burden, spacing, explosive diameter, and stemming-explosive length. Combined with previous work at this experimental quarry examining air gap, delay, and decoupling effects, this experiment provided a data base of over 50 shots. The fragmented rock, 1000 to 3000 kg from each 3- to 4-hole blast in the 1 m bench of massive dolomite, was completely screened to assess fragmentation. The explosive used for all the tests was extra dynamite initiated by seismic caps fired from a sequential blasting machine with delays of 5.2- to 13-ms/m of burden. Empirical equations were developed which predicted the effect of shot design parameters on the fragmentation. These formulas predicted the average fragment size of each of the 25-shots to within 13 percent. For spacing to burden ratios of 1, 1.4 and 2, there were optimum burden to explosive diameter ratios (B/de) of 30, 26 and 20, respectively. Decreasing the B/d. ratio beyond these levels resulted in little or no reduction in the average size. For B/de ratios above these levels the average size increased but, at least a 15 percent reduction in the average size results when the shot design parameters are optimized.

Jan 1, 1990

By R Nicholson, N D. Cox, N W. A Lambert

"This paper reports on the long-term operation of a particle density meter (PDM) at the Bloomfield coal handling and preparation plant (CHPP). This unit has been operating continuously for over three years, providing real-time data to the operators to allow the monitoring of flotation circuit performance. PDM outputs include slurry density, solids concentration on both mass and volumetric basis, and particle density. Knowing the average particle density of a stream allows for the optimisation of the process in real-time.The calibration of the solids concentration measurement device proved very difficult as the factory calibration techniques and existing laboratory analysis did not give accurate or reliable results. The solids concentration device had to be re-engineered and a new calibration method developed that gave accurate and repeatable results. Independent verification of samples taken from the PDM was undertaken as part of the trial process.The operational reliability of the PDM was a major point of investigation. The initial installation of the unit revealed issues with large, misplaced material of up to 20 mm periodically entering the unit, leading to feed blockages. The presence of these misplaced, oversized particles in the flotation circuit was resolved by installing innovative automatic back flush systems on the PDM.From a plant perspective the PDM has been an invaluable instrument that has enabled irregularities in the flotation circuit performance to be identified, which sampling had not and could not readily identify. This was achieved by close monitoring of real-time tailings composition on a minute by minute basis over short and extended periods. Variations in the tailings stream with respect to particle density and solids concentration were traced back to other issues in the plant. In addition, the PDM has allowed cell optimisation with respect to reagent dose rate to be improved. The PDM with real-time feedback can negate the need for large sampling campaigns and analysis during plant optimisation programs.Citation:Lambert, N, Cox, N and Nicholson, R, 2016. Particle Density Meter, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 245–250 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016