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Energy Dissipation in Long-Distance Slurry Pipelines

Sep 13, 2010

Study on Mineral Processing of Refractory Copper-Nickel Ore

Sep 13, 2010

By C A. Heinrich, J L. Walshe, V J. Wall

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

By J E. Nethery

At the Red Dome and Mungana deposits in north Queensland, Australia, it is proposed that mineralisation and alteration developed as a 'telescoped' overprinting continuum, ranging in style from hypothermal to epithermal, reflecting the major changes that developed in the regional setting over the period circa 325 - 290 Ma. Regional assessment suggests that this also applies to many other precious and base metal deposits within a 40 km length of the host Siluro-Devonian Chillagoe Formation.   A ten stage paragenetic sequence of structural preparation, multi phase intrusion and associated mineralisation, alteration and brecciation is postulated for the Chillagoe district.

Jan 1, 1995

Three methods of gold analysis are briefly described highlighting some of the problems and advantages of each. The variation of results between samples and splits and due to method of preparation is illustrated. The mean per cent difference of the fire assay values from the means of sample split values for three cases is 15 per cent.Finally, a comparison of the aqua regia leach atomic absorption spectroscopy (AAS) and fire assay fusion AAS techniques is made.This shows that the mean precision, the ability to obtain the same value, of the methods at 98 per cent confidence is ± 30 per cent and ± 15 per cent respectively. The fire assay fusion AAS method is relatively more accurate than the aqua regia one.

Jan 1, 1984

Operations of the new copper smelter at Mount Isa commenced on the 6th February, 1953. Prior to this date a paper by R. V. Anderson (1953) outlined the smelter layout, proposed operation and expected performance.Nominally a 50-ton per day plant, output is currently at the rate of 85 long tons per day. In the first 3t years, of operation to 30th June, 1956, '71,339 tons of blister copper were produced. Operation has been stabilized' and a number of modifications to plant and operation have been made. This paper reviews the progress made to date.GENERAL LAYOUT AND EQUIPMENTThe general layout and equipment follows well-established practice as study of Figs. 1 to 4, and Appendix II will show. This diagrammatic representation of layout (Fig. 1) and flow sheet (Fig. 2) is intended for the purpose of brevity to take the place of a detailed plant description.Choice of site for the smelter was limited by the necessity for close proximity of the waste heat boilers to the powerhouse.Much excavation was necessary before foundation work commenced, but the plant is compact and further expansion is possible.CHARGE MAKE-UPRoaster charge initially comprised concentrates, purchased ores, revert materials, mine sulphide ore and barren sand. As purchased ore receipts increased and as domestic black rock oxidized ore became available, the latter two fluxes were eliminated from the charge. Fluxes at minus i-in. sizing are trucked from crushing plant or stockpile by motor lorries. Filtered mill concentrates are dropped from an overhead conveyor on to the storage patio floor adj acent to the two concentrate bins.

Jan 1, 1957

Iron production in one year exceeds that of all other metals combined in ten years. It is a huge industry that started from a modest furnace producing one - two kilograms metal per day to a gigantic reactor producing 10 000 tons per day. The major milestones of these developments are reviewed.

Jan 1, 1999

By G J. Massoth, K Faure, A G, R G. Ditchburn, I J. Graham

From modest beginnings in 1996, research into the mineral potential of New ZealandÆs Exclusive Economic Zone has progressed into a major multidisciplinary component of GNSÆs recently funded 6-year æMineral Wealth of NZ and its EEZÆ Programme. In excess of $7.5 M of research funding has been expended, plus $10 M leveraged via collaborations with NIWA (NZ), NOAA (USA), JAMSTEC (Japan), U. Kiel (Germany) and ANU (Australia), whose scientists have contributed hugely to research cruises, as well as subsequent analysis and publication. The 1999 NZAPLUME I cruise was the first research expedition to systematically locate, and chemically characterise, submarine hydrothermal venting associated with arc volcanoes of the southern part the Kermadec intra oceanic arc system. This was followed by the 2002 NZAPLUME II and 2004 NZAPLUME III cruises to the mid- and northern-sections of the Kermadec arc, respectively. Combined, these cruises have surveyed 1300 km of the volcanic chain (from Whakatane to Monowai), including 34 major volcanic centres. Together with concurrent surveys in the Tonga arc, this is now the longest continuous stretch of intra oceanic arc to be surveyed for hydrothermal emissions. Most of the volcanic centres are characterised by simple cones although 30 per cent contain caldera complexes, and compositions range from basalt through to rhyolite. Massive sulphide mineralisation has been recovered from several volcanic centres in the southern Kermadecs (Clark, Rumble II West and Brothers), suggesting the existence of significant Au and base metal bearing deposits along the arc front.

Jan 1, 2005

The Government signalled its intention in the Economic Statement on 17 December 1987 to improve the fairness of the taxation system and to facilitate the process of economic adjustment by: removing tax concessions that benefit some taxpayers at the expense of other taxpayers,ensuring that those who can afford it shoulder their fair share of the tax burden,securing a revenue base which will provide sufficient resources to maintain effective social services,reducing artificial protection and concessions that discriminate against some sectors, and encouraging confidence through an economic environment with a medium-term orientation. The Government has clearly stated to all sectors that tax preferences will be phased out and businesses need to look inwardly to their investment policies if they are to survive in an open economy. This paper will address the effect of these Government objectives on the taxation structure for all forms of mineral exploration in New Zealand. The present tax structure will firstly be analysed, in particular setting out the tax advantages available to the industry. The effect of changes to the tax system within the recent past which relate to mineral exploration will then be examined. Finally the paper will address the question of possible future changes, particularly in the light of Government's intention to move towards a tax system which does not provide an advantage for any one sector of the economy.

Jan 1, 1988

Effect of Activated Carbon on the Leaching of Cobalt-Rich Ferromanganese Crust in Sulfuric Acid

Sep 13, 2010

Recent work on decoppering lead is reviewed CUS is formed rapidly even from dilute solutions of copper in lead. The mechanism of decoppering is discussed and an explanation for the retention of metals such as silver in lead is advanced. As decoppering tin appears to be an analogous process, the, Cu-Sn-S system is studied at 300°C.. CuS, which is not an equilibrium product, is found m decoppermg drosses. In the removal of nickel from lead, Ni3Pb2S2 is formed; preliminary measurements show the equilibrium nickel content to be greater than that obtained by stirring in sulphur. Decoppering bIsmuth IS thermodynamically favoured, but is complicated by the occurrence of CuBiS2 The Cu-Pb-S system IS the only one of the four studied where the equilibrium can be calculated simply, as the presence of ternary sulphIde or other phases invalidates calculations based on binary data.

Jan 1, 1971

By T Higuchi, L Lu

The quality of iron ore fines have been deteriorating, which has affected sinter quality and productivity adversely. New pretreatment and sintering technologies are therefore required to tackle the gradual change in the quality of iron ore fines. In the sintering process, iron ore fines are first granulated with fluxes such as limestone and coke breeze, and are then loaded and fired in a sinter machine. Sinter productivity and quality are heavily influenced by the reactions occurring in the sintering bed. Hence fundamental understanding of these high temperature properties of ores is urgently needed.Formation of initial sinter melt, penetration and assimilation of nucleus particles by the initial melt, and consolidation and final solidification of final sinter melt are believed to be the key sintering reactions. The assimilation and penetration phenomena have been studied separately in the literature with model particles and diffusion couples and are therefore difficult to relate to sinter quality. In addition, the effect of ore mineralogy has not been studied in detail.In this study, tablets consisting of coarse particles from various iron ore fines as nucleus particles and chemical reagents as adhering fines were made and fired under various sintering conditions to investigate the penetration and assimilation behaviour simultaneously. The degree of assimilation, pore structure, compressive strength of the resultant analogue sinters were evaluated and the relationship between sinter strength and ore characteristics was further discussed. The nucleus particles from Ores A and B were found to be more porous and assimilated more readily with sinter melt, resulting in a viscous melt and a macro-porous sinter structure. The nucleus particles from Ores C and D on the other hand, assimilated less readily with sinter melt, resulting in a fluid melt and a denser sinter structure. This is consistent with the results reported in the literature, suggesting that the present evaluation method can be utilised for studying sintering reactions and predicting sinter quality.CITATION:Higuchi, T and Lu, L, 2017. Evaluation of sintering behaviour based on ore characteristics, in Proceedings Iron Ore 2017, pp 303–308 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By F Farías, D Villa

Codelco’s Salvador Project has been operating a block/panel caving mine for more than 50 years. This underground mining method dynamically mixes the ore and dilution. As a result, forecasting grades is difficult and achieving 100 per cent extraction of the reserves is practically impossible. A substantial volume of the ore mixed with dilution becomes remnant ore and remains to be subsequently extracted.A potential open pit mine is under evaluation at Codelco’s Salvador Project, which includes the extraction of remnant ore post-block caving extraction. An effective methodology has been implemented to estimate what is left behind once the underground mine has closed. A new mixing method using the Cellular Automata (Alfaro and Saavedra, 2004) approach has been used to allow estimation of the remnant ore with a sufficient level of confidence to be included as part of the open pit reserve.A remnant block model is created using elements such as in situ block model, drawpoint layouts, historical production records and the drawpoint extraction. Using this information, simulations of the extraction of the mine by month from 1959 to 2019 were completed, using different mixing scenarios and trying to replicate the tonnage and grade extracted.Finally, the remnant block model is categorised using a score card with four inputs to assess the risk of the estimation of this material into a category class (measured, indicated and inferred).CITATION:Villa, D and Farías, F, 2016. Remnant ore model generation and categorisation post-block caving extraction at Salvador Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 461–470 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Matters C. W

THE following paper embodies the present practice and the results of past experience in the survey departments of two of the leading Broken Hill mines, the Central (Sulphide Corporation Ltd.) and the Broken Hill South S. M. Co. N. L.The authors intend to limit the scope of this paper to a consideration of office methods, as much has recently appeared in technical literature concerning field work, both surface and underground. Special reference may here be made to a valuable paper on 'Mine Surveying' by H W Gartrell, in Vol XIII of Transactions, in which the author gives considerable attention to field work. Moreover, much of the office work described in current literature is American, and sometimes not suited to local conditions, being ·often exceedingly elaborate and demanding a large staff of assistants. It is believed that the methods of recording information described in this paper are sufficiently simple and flexible to be adapted to most Australian mines. Brief acknowledgement must be made to the work done by Americans, who have raised mine surveying to the position of a separate profession, instead of being merely an unimportant branch of land surveying.

Jan 1, 1912

The mining industry is generally regarded as a high risk industry, mainly because of the difficulties in estimating the tonnage and grade of mineral resources, the fluctuations in metal prices, mining problems and other problems which occur with mining in offshore and remote locations, such as appropriation or disruption to supply. As a consequence, finance providers require a high reward from mining projects. In the past two decades, the development of "mega" projects has led to the packaging of the finance becoming more sophisticated. Some would see this move as a measure of the evolution of banking rather than an intrinsic facet of mining finance itself. Project financial managers now require a thorough knowledge of all the financial tools which are available and have to be aware of the funding options so that they can put together a finance package which minimises the cost of the financing with the risk spread adequately between the partners of the financing. The different sources and types of finance for mining projects are described herein along with the factors which determine their costs. To understand the ramifications of financing mining projects, it is essential to appreciate the fundamental difference between debt and equity, which illustrates the importance of gearing. Costs of finance are determined by the interaction of supply and demand forces. Bankers and other financiers have become more adept at isolating a wide selection of risk elements and have devised a formidable range of insurance mechanisms. There is still a lot of money looking for good project risks and if a good project is properly presented and structured, financing can be obtained in today's market.

Jan 1, 1990

By O A. Cottrill, G A. Oldfield, S B. Nowell

Host-rock û wallrock major and trace element geochemistry associated with epithermal gold mineralisation in the Hauraki Goldfield of New Zealand is poorly documented, even though rock geochemistry is a recognised tool in exploration. Such responses assist in recognition of the regional scale imprint of fossil hydrothermal activity, and indicate targets for detailed evaluation within these alteration zones.   Recent investigation of gold deposits in the Waihi (Gladstone), Golden Cross (Empire), Thames (Waiotahi) and Coromandel (Tokatea) areas indicate enrichments of Au, As and Sb in the andesitic wallrocks hosting mineralisation. Of the other elements examined, Si, K and Rb are enriched, and Na, Ca, and Sr are depleted at all deposits. These trends are best developed in the vicinity of veining. In deposits with clay alteration dominating (Waiotahi and Tokatea) there is also depletion of Mg, Mn, Zn and Cu. Ba and Cr are variably enriched or depleted within different styles of alteration. Base-metal enrichment in the wallrocks is not a feature of Hauraki deposits.

Jan 1, 1990

By T F. McConachy, B I. A McInnes, R A. Binns

Within the last decade, major research discoveries have been made in the submarine realm of magmatic and hydrothermal activity of arc-backarc systems in the southwestern Pacific. These include identification of numerous particulate-poor, gas-rich (CO2-CH4) hydrothermal plumes emanating from arc front volcanoes, actively forming porphyry-copper-gold style mineralisation, and new backarc spreading systems erupting alkali basalt-trachyandesite magmas. Major goals of these studies have been identification of modern analogs to ancient volcanogenic massive sulfide ore bodies, and quantification of the volatile fluxes though supra-subduction zone systems.

Jan 1, 2002

The spatial and temporal evolution from the porphyry to high-sulphidation epithermal environment can be assessed by integrating new results on such deposits (Arribas et al, 1995; Hedenquist et al, 1998) with past studies of plutonic and porphyry systems (Dilles and Proffett, 1995; Cline, 1995; Shinohara and Hedenquist, 1997; Hedenquist and Richards, 1998). Some time ago, Sillitoe (1973) argued for the nature of the tops and bottoms of porphyry deposits. He concluded that epithermal deposits may form over the tops of some porphyry systems. We can now conclude more confidently what the tops and bottoms of many high-sulphidation ore deposits appeared like while active (Arribas, 1995; Hedenquist, 1995). In addition, we better understand the nature of the zonation of high-sulphidation epithermal systems from the intrusive to surficial environment (Sillitoe, 1999), and how these two styles of ore deposit are related. Geological and geochemical evidence clearly indicates a continuum between these two ore environments. This improved understanding of genesis allows more efficient exploration for these deposits. There are many examples of spatially associated porphyry and epithermal ore deposits. A genetic connection has been suggested by some, and argued against by others. Nowhere is this spatial association better seen than in northern Luzon, Philippines, where the Lepanto high-sulphidation epithermal Cu-Au deposit overlies the Far Southeast (FSE) porphyry Cu-Au resource (Figure 1). Together these mineralised bodies contain a resource of >3.8 M tonnes Cu and >550 tonnes Au. Lepanto was largely mined out in early-1997. Post-war production until 1995 was 0.73 Mt Cu, 115 t Au and 393 t Ag at an average grade of 2.2 per cent Cu, 3.5 g/t Au and 11 g/t Ag. The recent discovery of the adjacent Victoria low-sulphidation quartz-Au-base metal vein deposit, with a resource of >68 tonnes Au (Cuison et al, 1998), illustrates the variety and abundance of mineralisation in the Mankayan district. This district also hosts the Guinaoang porphyry Cu-Au deposit (Sillitoe and Angeles, 1985) and other epithermal vein occurrences (Figure 1). This brief summary reviews the results recently published on the Lepanto-FSE deposits (Arribas et al, 1995; Mancano and Campbell, 1995; Claveria, 1998; Hedenquist et al, 1998), and stresses the evidence for coupling of mineralisation between the porphyry and high-sulphidation epithermal environments.

Jan 1, 1999

Flow Sheet Simulation of Municipal Waste Treatment Processes

Sep 13, 2010

The prime objective of geometallurgy is to improve the profitability of mines through the use of spatial models of rock properties that have a significant impact on value. Although a key property is the grade of the component of interest, because it directly influences the revenue from saleable material, increasingly attention is being focused on other attributes. These 'non-grade' variables may have a less direct, but equally profound impact on value, either by reducing potential revenue (eg lowering recovery, deleterious elements, etc) or increasing mining or treatment costs (eg comminution, grindability, throughput, reagent use, etc). Collectively, these variables have been described as 'geometallurgical'. There are three main areas of activity required to realise the value of geometallurgy: 1. acquisition of appropriate data through sampling and measurement, 2. building spatial models of geometallurgical variables, and 3. using these models to optimise value. Each of these is built on the foundation of the preceding step. In building reliable spatial models, it is critical that the amount of error introduced to data by the sampling and measurement processes is understood and quantified, in order that the inherent variability of the component of interest can also be properly understood. Management of the quality of grade variables is now applied (with different levels of diligence and success) across nearly all sectors of the mining industry, not least because of the necessity to adhere to Codes of practice (eg JORC, 2004). The necessity for quality management and at least the broad framework of what to do in practice is reasonably understood by many relevant professionals. There are also a number of tools, including software products, statistical analyses and presentation formats, available for those managing grade data. It is also abundantly clear, that in many cases people have little understanding of why they are doing particular quality control activities, or how to sensibly interpret the results. The same is not true for many geometallurgical variables. In almost all instances the authors have seen, the magnitude of sampling and analytical/measurement error variance embedded in geometallurgical test data is untested and unknown. This is partly because until relatively recently, metallurgical data has mainly been collected for the purpose of process and mill design, with few, expensive tests carried out on 'average' samples of the orebody. Increasingly however, there is a move towards collection of much larger data sets from spatially distributed sampling, and thus a growing necessity to understand the errors inherent in both sampling and analysis of these types of variables, and how to manage them. In order to understand how the quality management practices applied to grade variables can be extended to geometallurgical variables, it is essential to understand the theoretical foundation that supports these practices. This requires an analysis of the concepts that underpin the 'principles of additivity' (Matheron, 1963), the 'theory of sampling' (Gy, 1982, Pitard, 1993), and 'statistical process control' (Shewhart, 1930). Relevant concepts are then integrated to form a foundation to develop methods to improve the quality management of geometallurgical variables. Application of this framework will significantly increase the integrity of geometallurgical data, the reliability of geometallurgical models and ultimately the value derived from implementing geometallurgy. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Mar 1, 2010