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Enhance Fine Particle Flotation by Hydrodynamic Cavitation Difficulties in fine particle flotation are well documented. Microbubble flotation has been found to greatly improve the recovery of fine particles and in situ gas nucleation by hydrodynamic cavitation incorporated in the design of modern flotation machines has shown great performance in fine particle flotation and potentially in coarse particle flotation. In this presentation, we will provide an overview on gas nucleation by hydrodynamic cavitation and its role in fine particle flotation with focus on the progress made in our research laboratory. Hydrodynamic cavitation was achieved and the critical role of dissolved gases in the liquid was elucidated by visualisation in a high intensity agitation cell. The in situ gas nucleation on fine particles by hydrodynamic cavitation was identified by zeta potential distribution measurement in model systems. Gas nucleation by hydrodynamic cativation was found to effectively aggregate hydrophobised fine particles thereby leading to enhanced flotation kinetics. This is an abstract only. No full paper was prepared for this presentation.

Sep 13, 2010

By Y Sha

During the last two decades, China has expanded its iron and steel industry very quickly, from less than 100 Mt/a steel production to over 700 Mt/a. It caused big increases in both domestic iron ore production and imported iron ore quantities year by year. The mode of iron ore supply has changed from almost all domestic supply to major tonnes of imported ore plus domestic ore supply. Over 200 blast furnaces with volumes larger than 1000 m3 each have been built and put into operation. Sinter machines have been enlarged quickly. There are now 135 sinter machines with =200 m2 sintering area each. Pellet production increased from 11.94 Mt in 1999 to 210 Mt in 2011, resulting from rapidly increasing domestic concentrate supply and rapid development of the grate-kiln process. The typical ferrous burden constitution is high basicity sinter plus pellets plus lump. The pellet proportion increased and the sinter proportion decreased gradually. A lot of technical improvements, like deep bed sintering, sintering with a high ratio of limonite, composite sintering, pellet process optimisation, a high ratio of hematite in pelletisation, blast furnace operation with low-grade ferrous burdens and hazardous element control, etc have been made to enhance iron burden quality and to reduce hot metal cost. Chinese iron and steel production is expected to increase slightly in the next few years. Its overcapacity should be controlled effectively. Given the variations of iron ore supply, pellet production will keep progressing in terms of production scale and pellet quality, the sintering process will be improved further by various measures to utilise different ores efficiently, and ferrous burden constitution will be optimised continuously to realise the lowest cost of hot metal production.CITATION:Sha, Y and Wang, Z, 2013. The Chinese iron and steel industry response to the challenges of iron ore supply, in Proceedings Iron Ore 2013 , pp 7-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By P L. McCarthy

In an environment of accelerating capital costs, limited capital availability and strongly cyclic metal prices, there is a difference between a robust mining and processing operation and one that would maximise shareholder returns in an idealised world. A higher cut-off grade policy is likely to improve operating margins and may reduce the scale of operations and thus limit capital exposure. This will leave some metal in the ground, but it is marginal material which carries the greatest cost and risk exposures. Where do we draw the line?CITATION:McCarthy, P L, 2013. Is bigger better? Building market resilience into process plant design, in Proceedings MetPlant 2013 , pp 66-70 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By N Madani

Linear interpolation of geo-related variables is important to different aspects of mining engineering such as long and short-term mine planning. The ore deposit description attained from spatial modeling of blast hole datasets has been widely taken into account, particularly, for short-term mine design and grade control, so as to define the ultimate destination of a mined block. It is approved in practice that making the wrong decision leads to losing a huge amount of money for choosing the destination of a mined block. In the case of complex ore deposits, the issue of estimation of variables in the region is questionable and somehow tedious. Due to this fact, modeling those complications in the co-spatial behavior of the grades in multi-element deposits prompts one to employ enhanced geostatistical techniques. Traditional approaches of this purpose such as polygon, inverse distance weighted and even (co)-kriging approaches, are incapable of reproducing those complexities such as non-linearity, heteroscedasticity and geological constraint that frequently exist among the variables of interest in those deposits. Another difficulty in employing those linear interpolations in grade estimation is smoothing effect, in which the estimated grades are over and under estimated. CITATION: Madani, N, 2018. 3D estimation of variables with complexity in cross-correlation structures, in Proceedings Complex Orebodies Conference 2018, pp 49–52 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By S Hapugoda, A Edenton, M Adam, R J. Holmes, J R. Manuel, R Smyth

Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, normally accounting for ten to 20 per cent of the blast furnace burden. Like other feeds, the characteristics of lump ore have an important impact on the stable operation and productivity of the blast furnace. Lump ore is usually assessed chemically, physically and mineralogically to establish its likely blast furnace performance. The physical characteristics of lump ore are strongly related to the chemistry, mineralogy and texture of the ore involved. In this paper, the blast furnace ironmaking process is reviewed, with particular emphasis on the key quality requirements for the ferrous burden material. A variety of key physical characteristics of lump ore measured using standard and non-standard methods are then described and subsequently correlated with the chemical and mineralogical characteristics of the ore wherever possible. Finally, the impact of these physical characteristics on blast furnace operation is assessed.

Jan 1, 2009

By Robinson WB

An accurate and rapid assessment of coal resources, such as that provided by computer modelling, forms an intergral role in evaluating CSR's coal deposits for future development. An in-house system utilising a number of geological, engineering, costing and financial evaluation routines has been developed for DEC VAX computers. The system is currently being upgraded and enhanced to meet the demands at the various mine sites. Computer modelling of the geology is performed on encoded drillhole information and coal core chemical and physical analyses. A conceptual mine plan is formulated then digitized and superimposed on the geological model. Insitu and product coal reserves and qualities as well as overburden and parting quantities are then calculated for each strip or block. These strip parameters are then transferred to the mine scheduling routines to determine the most efficient mining sequence for the mine plan. Cost factors and scheduling data for equipment specified in the conceptual mine plan are used in the mine costing subsystem. The financial subsystem then evaluates the likely return on investment. Future enhancements to the system include improvements in the response time through the introduction of interactive graphics, the direct interfacing of geophysical and analytical data, and further development of a geotechnical'database.

Jan 1, 1983

The Hall-Hoult process is likely to be the dominant method of aluminium production for the remainder of the century. The characteristics of the operation of a modern smelter are described and attention drawn to their disabilities which are due chiefly to the small production capacity of individual cells.The principal components of the Hall-H6roult cell - the electrolyte, the anode and the cathode - are discussed in order to identify the problems of scale-up. The factors influencing current efficiency and energy consumption are analysed and lead to the conclusion that the greatest potential for energy saving lies in reducing the anode to cathode distance (ACD).The most promising direction for major change is in the application of a new titanium diboride - carbon composite for coating of the surface of the cathode carbon. It improves the wetting of the carbon by aluminium and should permit the use of sloping cathodes and anodes. The deep metal pad would thereby be eliminated and, in the absence of magnetic perturbations, the ACD could be substantially decreased.The construction and testing of a full-size "Low Energy Cell" is scheduled for early 1986 and is expected to reduce energy consumption in aluminium production by about 15%.

Jan 1, 1985

By A G. Grice

WMC Resources Pty Ltd û Copper Uranium Division operates the large underground Olympic Dam Mine at Roxby Downs, South Australia. These operations mine and process the ore to produce refined copper, uranium oxide, gold and silver. In mid-1996, the company committed to the Olympic Dam Expansion Project (OEP) to expand production from 3.0 million tonnes per annum of ore (85 000 tonnes per annum of copper metal) to over 9.0 million tonnes per annum of ore (over 200 000 tonnes per annum of copper metal). Along with the increase in the ore production capacity of the underground mine and the surface ore handling and processing facilities, expansion of the backfill system was required. The target backfill placement rate was 2.0 million cubic metres of backfill per annum which was to be predominantly delivered as cemented aggregate fill (CAF). This paper discusses the engineering activities undertaken to assess and change the method of designing the required strength of fill exposures. In addition, the operational changes that were introduced to achieve the required fill quantities and the mix designs to meet the specified strengths, including the use of alternate binders, are discussed. This work resulted in a large increase in the fill placement rate and a reduction in the overall unit cost of fill.

Jan 1, 2000

The underground storage of LPG and other hydrocarbons is in current commercial use in Northern Hemisphere countries in Europe, Asia and the USA.Elgas Pty Ltd, a 50 per cent joint venture between AGL and BOC, embarked on a worldwide feasibility investigation in 1989 to establish the viability of constructing an underground LPG storage facility in Sydney, Australia, the first of its kind in the country. Elgas recognised that with the limited 19 000 tonnes of storage capacity at Port Botany and the limitations imposed by use of small coastal ships (up to 10 000 tonnes capacity), a larger storage facility was required to utilise higher capacity ships from more remote sources such as the North West shelf and overseas. This would achieve security of supply in high demand periods and economies of scale. The underground option also provides improvements to safety and environmental standards.

Jan 1, 1999

By Cai S, Zhou C

The requirement of mineral resources is increasing as the economy is continually increasing in China. The mining practices of various complex sulphide deposits and precious metal deposits, and the treatment of mine tailings and other industrial solid wastes, have greatly improved fill quality in the metal mines. From early-1980s, high density slurry fill, paste fill of total tailings, low density slurry fill with addition of silicate gelling agent, etc has been studied and applied, and some progress has been achieved. Today, mine tailings, slag and power plant ash are widely used as fill materials in mining. A number of cemented fill mines equipped with large capacity trackless mining machines are in production. Recently, The 3rd Chinese National Symposium on Mining with Backfill, 1995 has been held, the progress of fill technology in mines has been exchanged and summarised. In the paper, some aspects of fill technology used in the metal mines of China are briefly introduced and some applications of fill research work are presented.

Jan 1, 1998

By J Emslie

Newmont AustraliaÆs Callie Underground Gold Mine is located on the Dead Bullock Soak Mining Lease, approximately 600 km NW of Alice Springs, NT, in the Granites-Tanami Goldfield. Dead Bullock Soak is part of NewmontÆs Tanami Operations, which also include the Granites Gold Mine and processing plant, Groundrush Open Pit and Tanami Mill. Callie is a world class Proterozoic gold deposit; production to date is in excess of 1.7 million ounces, with an additional Proved and Probable reserves at the end of 2002 of 10.8 Mt at 6.3 g/t. Gold mineralisation at Callie occurs in thin (1 - 30 mm) steeply dipping quartz-chlorite sheeted vein system that cuts across a 40¦ plunging folded sequence of medium to fine-grained metasediments. While the vein system is highly continuous, the gold distribution is highly variable and is controlled by the interaction of lithology, alteration, structure and vein density. The mineralisation is commonly coarse-grained and has a relatively high nugget effect, consequently the orebody is problematic to estimate and shows a high degree of sensitivity to drill hole density. Resource modelling at Callie is an example of a geologically driven model that has evolved with increasing data and understanding. Lithological and structural models are employed to define domains within which the grade estimation is undertaken using multiple indicator kriging. This gradual model evolution impacted greatly on the selection of the mining method. Uncertainty in the estimation of the orebody was a significant factor that led to sublevel open stoping with cemented aggregate fill being adopted as the mining method to improve extraction selectivity. Callie often shows strong positive reconciliation compared to the mill. The mine geologistÆs face the challenge of limiting the degree of underestimation of the core of stopes whilst ensuring that stope boundaries are not conservative. This can only be achieved through the mapping of subtle geological features in order to confirm the orebody model. The increased use of the geological mapping has improved our understanding of the controls on mineralisation and has been extended into the development of new models for near mine underground exploration.

Jan 1, 2003

By A Baensch, E Grimsley

Eloise Copper Mine is situated 56 km east-southeast of Cloncurry, Queensland, Australia. The deposit was discovered by BHP Minerals in 1986 during follow up diamond drilling of EM anomalies associated with major aeromagnetic anomalies. The deposit is overlain by 60 m of Mesozoic cover. Amalg Resources NL commenced mining during 1995 by means of decline access and long hole-stoping. The total mineral resource comprised 1.77 million tonnes at 4.10 per cent Cu as at the end of June 2003. Proved and probable reserves are 930 000 tonnes at 3.97 per cent Cu. Mineralisation is hosted within a strongly foliated Proterozoic meta-sedimentary sequence comprising arenites and schists. The metasediment sequence also contains a coarse-grained amphibolite body possibly representing an early intrusion of gabbroic composition. Economic mineralisation characteristically occurs as a number of steeply plunging lenticular bodies with strike lengths of between 100 and 200 m and maximum widths approaching 25 m. The principal orebody, the Levuka (B) Lode, displays a down plunge extension exceeding 1000 m and is open at depth. Ore mineralogy is almost exclusively chalcopyrite with the principal gangue phases consisting of pyrrhotite + quartz + carbonate. A biotite + hornblende + magnetite assemblage represents locally intense mafic alteration of the metasedimentary host sequence. Magnetite is present in variable amounts and may be locally significant in some of the smaller satellite orebodies. Within the orebodies the sulfides display a range of textures from massive through to vein like. Sulfides commonly display brecciated textures at a range of scales. Post-mineralisation faulting has severely dislocated the orebodies, resulting in a complex arrangement of fault bounded ore blocks. These faults display considerable variability in regard to strike, dip and amount and direction of throw. A recent review of the fault system by means of large-scale structure underground mapping, re-interpretation of drill core and 3D modelling has led to a significant improvement in the understanding of these structures. A significant upgrade of the geological database has accompanied the structural review. The overall improved understanding has aided the mine design processes with particular regard to decline and access development and pillar location. This has also impacted on the design of drilling programs and exploration for additional satellite ore zones.

Jan 1, 2003

By Met B. E

The increasing pace of modern mining makes constantly greater demands upon the several contributing departments of rock breaking and transport, and rock-drilling, as the spearhead of attack, has received a great deal of attention with respect to both machines and steels. By a series of mechanical improvements, combined with the application of selected heat-treated alloy steels, the rock-drill has now been developed into a machine capable of rapid drilling and long service under severe working conditions. As a factoryproduct made under strict metallurgical control it is as foolproof as, say, the modern automobile, and, like its prototype, it can be kept in efficient operation by a minor amount of attention during use and by periodical adjustments and replacements.The same cannot be said, unfortunately, of the drills with which the machine is supplied; in conventional mine-shop practice these are made of the best tool steel shaped and heat-treated under the poorest of metallurgical conditions.The crudities of steel-shop practice have, in fact, always prevented the full exploitation of the steels available at any time, and even at the present day the general standard of treatment offers a contrast with the quality of the steels which moves the metallurgist to amusement, despondency or outrage, according to his temperament. Nevertheless, the tendency persists to meet the increasing demands of the rock-drill primarily by the use of still better steels, and secondarily by improvement, of the steel-shop practice. Athird type of development is the introduction of factorymade tools in the form of detachable bits and rods. It is proposed in this paper to deal with these three aspects of the recent developments in rock-drilling.*Re-written from a lecturette given during the First Ordinary Meeting, 1936.

Jan 1, 1936

Open pit mining at Bingham Canyon commenced in 1904 and about two billion tonnes of ore have been extracted since then. There remain just under one billion tonnes of ore in the pit and this will be mined by 2015. Because the porphyry system extends below the ultimate pit limits, Kennecott Utah Copper Corporation initiated a study in 1997 to determine the viability of underground mining. The study was initiated at that time because the results were to be used to compare the economics of a further pit expansion to that of an underground mine. If a pit expansion was viable then overburden removal would have to start in the near future. This paper is a summary of the work that was carried out for the underground study. Block cave mining was determined to be the most appropriate method to mine the deposit. Two block cave areas have been planned with a total production rate of 72 500 tpd. Additional sources of ore will come from skarn orebodies that are associated with the porphyry deposit. The geology of the deposits is described together with the geotechnical techniques that were used to characterise the rock in the absence of more detailed data that are normally available. A general description of the mine plan is given along with the reasons for selecting the particular methodology used. The study was completed at the end of 1998 and demonstrated the viability of underground mining at Bingham Canyon. Funds have been approved for further drilling and technical studies, which will lead up to a feasibility study in 2004/5.

Jan 1, 2000

A research project was commissioned by the Australian Coal Association Research Program (ACARP) to improve the understanding of tailgate strata mechanics and to provide a more rigorous engineering basis for tailgate support design. A deformation mechanism termed æskew roofÆ was defined which relates the regional influence of differential horizontal strata movement (shear) about longwall extraction to gateroads. Confirmation of the mechanism was achieved by field investigations which included measurement of the shear displacement along weak interfaces. Under geological and mining conditions where the skew roof mechanism operated, strata units were found to move progressively further towards the goaf with height into the roof. 3D numerical modelling was used to assess the major geotechnical factors controlling the mechanism and to determine appropriate support strategies within a æskew roofÆ environment including the role of cables versus standing supports. The skew mechanism is considered relevant to; all roadways in the vicinity of longwall extraction including the faceline itself, chain pillar design, and support design.

Jan 1, 2005

By Whitmore R. L

The action of water on a number of Queensland shales which are associated with particular coal measures and oil shales has been studied. The results suggest that the disintegration of some of the shales could cause significant problems in mining and preparation operations. The extent of shale breakdown varies widely from deposit to deposit and from seam to seam but a suitable assessment procedure utilises the test described in AS 1661-1979, and an improved method of presenting the results is described in the paper.

Jan 1, 1982

By X Li, R Chu, X Deng

The hot-dip galvanising industry is the largest consumer of zinc, with over 40 per cent of the world’s total annual production of zinc used for galvanised steel. The dross generated in the hot-dip galvanising coating process is a valuable co-product, since it contains high quantities of recyclable metal. A new method to recover the metal from the industrial galvanising dross was proposed using supergravity separation. During the hot-dip galvanising process, the presence of zinc dross has a serious impact on the surface quality of the hot-dip galvanised sheet, forming zinc dross defects. To reduce the impact of zinc dross, the zinc dross on the surface of the zinc pool needs to be manually or mechanically removed at regular intervals. However, during the dross removal process, a large amount of metal zinc is inevitably carried out, resulting in low zinc utilisation rate and high zinc loss rate. This article proposes an efficient and low-cost technology for the recycling and utilisation of hotdip galvanised dross, which uses super-gravity technology to recover hot-dip galvanised dross online. The metal in the hot-dip galvanised dross returns to the zinc pot in situ, while a small part of the dross remains in the super-gravity equipment, which can reduce the amount of zinc dross by more than 60 per cent and achieve a reduction in zinc loss from 17 per cent to less than 7 per cent.

Jun 19, 2024

By J Field

Many aspects of water use in mining are driven by the technical requirements for water. There has been little consideration given to both the safety and the health requirements. Workers in the mining industry are exposed to water from a range of treated and untreated sources. The intended use of this water dictates the required quality of the water, sometimes with limited consideration for contact with miners. Particularly for underground workers, there is exposure while working in and walking through groundwater possibly contaminated by hazardous substances. Where controls are inadequate the outcomes of this exposure can result in disease, illness and injury û the costs of which can be significant. The situation could also arise where, due to the lack of human exposure, the controls are unwarranted and the financial cost unjustified from a health perspective but warranted from an equipment management standpoint. In addition to the health aspects, water can impact on a range of safety issues resulting from high pressure usage, dust suppression, fire fighting and other processes. The protocols and procedures in place need to consider the safety issues in addition to managing water usage. The current state of water management in mines from an occupational health and safety perspective has been ascertained from a survey targeting underground and surface coal and metalliferous mines. This survey considered the health and safety issues associated with water use, the types of surveillance, control protocols and the strategies that the mines have in place to manage the health and safety risks associated with water systems. The results assisted in the identification of potential occupational health and safety risks associated with water systems and the management processes that may be appropriate from a risk management perspective. Health and safety issues are often neglected but remain critical issues affecting the value of water to the mining industry.

Jan 1, 2006

By E McLean

The decision making check-list and hierarchy of information for process and plant design is generally wide-ranging and complex. The nature of grades, mineralisation and ore types in an ore body, its mine development sequence, and the body of results from metallurgical and physical test work present complex and competing influences on flowsheet development, values for design, equipment selection, plant efficiencies and operating strategy. The challenge is how to manage all these variables, to understand their impacts on performance, and how best to provide a cost-effective plant design and robust process that meets daily/weekly/monthly operating objectives. Throughput, production and grade or product specifications need to be met. The ore body is not average; its range of metallurgical and physical characteristics may be moderately to highly variable. This paper assesses some of the key competing influences and conflicting issues in design and equipment selection, and their effect on production and performance expectations.

Aug 8, 2011

A number of cooperative studies have been carried out as preliminary work for drafting a standard for application of granulated slag sand for concrete, and the following conclusions were reached 1 The ten kinds of granulated slag sands pro- duced in Japan satisfy the national standard for fine aggregate in terms of physical and chemical properties. 2 Mortar and concrete tests conducted with granulated slag sand revealed that, although with slight differences in the extent, gran- ulated slag sands used in these tests were applicable'as fine aggregate for concrete, 3 The pumpability test by a concrete pump carried out on concrete with two kinds of now commercially available granulated slag sand demonstrated that the pump pressure feeding is applicable in the same manner as in the case of ordinary concrete. These tests permitted' preparation of a draft standard for application of granulated slag sand, and the results formed the first step toward utilizing this material as a sub- stitute for natural sand.

Jan 1, 1979