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By A Hosseinzadeh Barforoosh, A Abedi, M Taji

The effect of blast loads on beams is one of the main issues in the analysis of steel structure. In this study, experimental tests on steel beam under blast loading, and also numerical simulation by the Autodyn software to analyse these structures, is discussed. Experiments on steel beam size of 12 by Emulite4 explosive with 30 mm diameter and cortex is done. The patterns of cutting and bending generated in the two tests (empirical and simulation) show a good match.CITATION:Taji, M, Hosseinzadeh Barforoosh, A and Abedi, A, 2015. Comparison of experiment and simulation of blast loading on the steel beam, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 161–168 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By M L, G Maddocks, A Ferrier, ers, A Forbes

Evolution’s Mount Rawdon Operation (MRO) produces gold and silver through open pit mining methods. The mining operations are scheduled to be completed in FY24 (Financial Year 2024), after which low-grade stockpiles will be processed until the end of FY27. As part of MRO’s Progressive Rehabilitation and Closure Plan (PRCP), RGS Environmental Consultants (RGS) and Deswik were engaged to develop the final landform surface and a whole of site probabilistic water balance/water quality (WB/WQ) model to evaluate the viability of several closure options with respect to water quality in the various site water storages, particularly the final void which will form a pit lake. This case study details the closure option which included (amongst other things) covering the final landforms and directing water toward or away from the final void post closure. Closure and rehabilitation for MRO had previously been planned and evaluated on a ‘domain’ basis. Furthermore, the rehabilitation plans and final water management plans for the Tailings Storage Facility (TSF), Waste Rock Storage Facility (WRSF) and other domains were not coordinated, possibly resulting in competitive rehabilitation material requirements at the commencement of closure activities. An assumption was that a legacy non-acid forming (NAF) stockpile would provide sufficient material to both supplement ex-pit material for the construction of the TSF embankment raises and to complete all closure activities, but the volumes available and the volumes required to complete the closure activities had not been quantified.

Aug 2, 2023

The Southwest Pacific is a region of active volcanism and geothermal systems. Only in New Zealand have the geothermal systems been exploited for electricity generation and industrial processing. At present, approximately 280 MWe of geothermal electricity is generated in New Zealand. A considerable amount of further exploration work is required before the total geothermal potential of the region can be assessed and before the significance of these resources can be judged against other local energy sources.

Jan 1, 1990

Metal grades and contents of ore deposits should be measured in an unbiased manner, and with a degree of precision that reduces to an acceptable level the risk to put into production inviable prospects. The additive property of variances for metal grades and contents is used to assess the accuracy and precision characteristics of this measurement process. Each stage in the process of extracting different types of samples from ore deposits, preparing test samples from drill core sections, drill chips or crushed ore, and collecting and assaying test portions, contributes a variance component to the intrinsic variability of a metal's distribution in its matrix. Deducting such extrinsic variances results in more precise estimates for metal grades and contents of elementary units. The cumulative metal content for a set of elementary units of in-situ ore, and the sum of the variances for metal contents of all units in the set, can be used to calculate confidence intervals and confidence ranges at different probability levels as measures for risk.

Jan 1, 1976

Statistical frequency distributions may be used to characterize the overall variation of grade in orebodies. Special types of distribution (e.g. lognormal, log-type A) are necessary to describe skewness inthe case of rare metals. Also needed (but for the most part hitherto neglected) is the serial correlation function which describes the tendency for grades near together in an orebody to be closer together than grades at points relatively far apart.The sampling problem for orebodies is interpreted in statistical terms. Different methods are reviewed, and the effect of serial correlation discussed.A discussion is given, based on experiments and observations made by the author, of biases arising in the minei:l material by such methods as chip sampling and grab sampling due to such causes as nonrepresentative selection by the sampler.INTRODUCTIONMiners have always recognized the large element of chance in their operations. Chance is the raw material of statistical theory and, provided there is some recognizable pattern or underlying regularity in a set of data arising from the operation of chance events, statisticians are able to formulate mathematical models to study them. Mining engineers, geologists, and statisticians have gone a long way between them towards finding general statistical rules which describe the distribution of minerals and metals in orebodies, and even the distribution of orebodies over the earth's surface.These rules do not have the force of physical laws, though they obviously derive from them and have been used to throw light on them. From statistical theory it is possible to find methods of estimating from sampling some of the characteristics of orebodies which are of importance to...

Jan 1, 1962

By Finlayson J. F

The advantages of rapid and accurate analyses are becoming appreciated in many industries today and have resulted in a great increase in the number of samples received by their laboratories. This has caused some firms to consider the installation of one or more of the instruments available for analytical chemistry. In this country there are relatively few people with experience of instrumental methods and it is difficult for a firm considering the installation of such equipment to assess the advantages which instruments may give them, and to decide which instruments, if any, will be of most use to them. The object of this paper is to give a brief survey of instrumental methods in the field of inorganic analysis. Instrumental methods of analysis have numerous advantages when used correctly. They enable extremely rapid analyses to be made in many cases, e.g., analysis of refined lead by purely chemical means takes about two days whereas spectographically the analysis can be completed in approximately one and a half hours. The accuracy ofinstrumental methods, generally between 1 and 5%, is higher than most chemical methods for small percentages of impurities. Furthermore, if the instrument can be calibrated against absolute standards the errors are usually random and not biased to one side of the correct result. The sensitivity is high, enabling in many cases the detection and determination of smaller percentages than can be detected chemically. This high sensitivity enables and, in some cases, requires the use of very small samples, and results in considerable savings in reagents, allowing the analysis of considerably more samples without undue loss...

Jan 1, 1951

Inevitably the 'post-boom' era has changed the emphasis of many mining companies away from new project development and expansion to optimisation of existing operations. However, regardless of the project, high quality ore characterisation will remain of the utmost importance. In the case of new project development the need to understand the breakage characteristics will remain as important as it has always been. In optimisation projects, however, where it will be required to get the very best from existing comminution circuits, accurate geometallurgical modelling will take on an increasingly important role. However, these requirements, in both new development and optimisation projects, are likely to be at odds with budgets as these will be tight. Hence obtaining the best value for money will be essential. This paper discusses the elements that need to be satisfied for ore characterisation programs to be successful. Some of the issues covered will be: ore variability and sample selection, test precision, problems with the use of non-standard testing equipment, and the value of databases.

Jan 1, 2009

By X Xia2, X Wang, G Liang, T Song, F Ma

Inertia cone crushers have found applications mostly in steel slag crushing operations in China. Compared with conventional eccentric cone crushers, the crusher has an obvious advantage in reducing product size. In addition, they are mostly used in two-stage open circuit crushing flow sheet, which simplifies the crushing process. However, inertia cone crushers are not widely used in the mineral processing industry due to their low crushing capacity. In this paper, the throughput performance of the inertia cone crusher was investigated in a laboratory-scale inertia cone crusher and relationships between operational parameters were identified. Iron ore was crushed using orthogonal experimental method under different machine parameters and operational conditions. The crusher throughput and product size distributions were determined. The effects of parameters such as eccentric speed, discharge gap, eccentric mass and eccentric distance on product mass flow and product size were investigated. The results of this study can help reduce the feed size of the mill in order to reduce total energy consumption of comminution.

Aug 24, 2022

Traditionally, the term ætotal systemÆ design applied to comminution conjures images of a design that addresses the usual business and operational drivers, including health, safety and environment (HSE), capital cost, operating cost, throughput and product size. In terms of the physical process, the mine to customer type studies also exemplifies an approach that satisfies a normal ætotal systemsÆ approach. As an industry there are drivers that are forcing a re-consideration of what we regard as our total system. This modification of drivers will require changes in approach and implementation to provide the best solutions. Some of the major changes that impact the drivers are shortage of skilled personnel, changing social attitudes to remote mine site work, greenhouse gas emissions (GHGE), quality of available orebodies and geographical location of new mine sites. One approach to the challenges presented by the changing business environment is to expand the system envelope around comminution to ensure that comminution, in its widest sense, helps to meet the new realities. Background to the new drivers and constraints is provided and some of the appropriate responses are examined in relation to the impact on the total system.

Jan 1, 2007

By L Xiong, W J Shi, J H. Wei

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Baizhangzi gold deposit is located in the northern North China Craton. The structural and lithological controls on the location and geometry of orebodies were studied through geologic survey, ore spatial configuration analysis and structural analysis. The orebodies of the deposit comprise auriferous quartz-sulfide veins and disseminated gold-bearing sulfides. The auriferous quartz-sulfide veins are dominantly hosted by the NNE- (and NE- and NW-) trending faults, which are subsidiary structures of the regional NNE-trending F2 fault. The subsidiary NNE-trending faults, having sinistral reverse kinematics, are associated with the sinistral reverse kinematics event of the F2 fault, which happened under a regional S–N-oriented compression stress field. The subsidiary NE- and NW-trending faults appear to be compressive and extensional respectively. These NE- (and NW-) trending faults are restricted to the granite intrusion and are associated with a sinistral strike-slip event of the F2 fault, which reactivated under a NW–SE-oriented compression stress field. It makes significant influence on geological evolution and distribution of different ore types that the strike of the F2 fault presents significant transition from NNE- to NE-trending in vertical. The ore-bearing disseminated host rocks, with widespread silicification and pyritisation, distribute in the lower inner contact zone of the granite intrusion, especially in the lower wavelike boundary of granite intrusion.CITATION:Xiong, L, Wei, J H and Shi, W J, 2015. Structural and lithological controls on the location of orebodies in the Baizhangzi lode gold deposit in western Liaoning Province, China, in Proceedings PACRIM 2015 Congress, pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

The disadvantages of the present zinc producing methods, RLE and ISP, are high energy consumption and environmental problems. Therefore, efforts have been directed in Outokumpu Zinc towards the development of alternate routes. One interesting pyrometallurgical process to produce zinc is to inject zinc calcine together with a solid reductant into molten iron, saturated with carbon. This process has been studied by thermodynamic calculations, laboratory tests and mini-pilot test runs at Outokumpu Research Oy, Pori, Finland. The results of these tests are presented and discussed in this paper. The mini-pilot tests demonstrated that over 97 per cent evaporation of the zinc was possible using a reactive coal dust as the reducing agent. The recovery of zinc in the metal phase was at best 88 per cent of input zinc, but only part reported in molten lead in the splash condenser. The final metallic zinc contained at best 98 per cent Zn, the main impurities being dissolved lead and coal carried along with the flue dusts.

Jan 1, 1993

By I Ritchie, A Johnston, D Yataco

Marcobre SAC (Marcobre) is developing the Mina Justa copper mine project, located in the Ica region of Peru. The Mina Justa IOCG orebody comprises of a sulfide mass overlain by an oxide cap with a sharp transitional zone between the sulfide and oxide masses. The primary target metal is copper, but there are minor amounts of gold and silver. The oxide will be treated by HPGR, crushing and vat leaching, whereas the sulfide will be treated by HPGR, milling and froth flotation. The processing selections are due to some unusual ore characteristics which have required relatively unconventional solutions.Vat leaching was chosen over heap leaching and other processes after detailed trade-off studies found it to be the most attractive, primarily due to the high acid consumption of the ore. The sulfide flotation produces a wide range of concentrate grades due to the complex nature of the mineralogy. The selection of HPGR circuits for both the oxide and sulfide ore is due to the extremely hard and competent nature of the deposit. These factors and others have contributed to a unique process selection for this resource.The selection process for the oxide and sulfide ores, and an overview of the technology, equipment selection and geometallurgy, will be discussed.CITATION:Johnston, A, Ritchie, I and Yataco, D, 2017. Process development for the Mina Justa project, in Proceedings MetPlant 2017, pp 207–217 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

It is proposed to deal with those raw materials which are produced in South Australia to meet the needs of the country's steel industry. They are chiefly, iron ore, limestone and quartz.Iron ore and limestone are fed to the blast furnaces of Newcastle and Port Kembla together with coke to produce the hot metal charge for the open hearth steel furnaces.They are also qsed in the raw state in the steel furnaces to assist in the conversion of the hot metal to steel. The iron ore is quarried from' Iron Knob and shipped from Whyalla to Newcastle and Port Kembla, whilst the limestone is supplied from the deposits at Rapid Bay and shipped in the same manner.Quartz is used in the manufacture of ferro-silicon, an alloy which is added to the ladles of molten metal tapped from the open hearth furnace in the case of almost every grade of steel. It is obtained from a quarry situated between Iron Knob and Whyalla, and shipped to Newcastle.IRON OREWith the exception of several small quarries situated at Breadalbane, Cadia, Cowra, Crookwell, Michelago, Jerrawa and lerraama in New South Wales, the iron ore requirements of Australia's steel industry to date have been met from Iron Knob and the Middleback Range in South Australia.Several of the small deposits in New South Wales were worked during the war years of 1941-44 during the shipping emergency and produced 1,355,417 tons, compared with an output of approximately 43,000,000 tons from Iron Knob between 1901 and 1949.

Jan 1, 1951

By P Ramsaywok

The use of saline water for mineral beneficiation in arid regions is general practice and also the case with Exxaro Namakwa Sands, situated on the west coast of South Africa. Although it is ‘cost effective’ to use sea water for mineral beneficiation, downstream process separation efficiencies may be negatively affected. This is more specific to surface dependent separation techniques such as electrostatic and high tension (HT) separation. If minimal fresh water is available then, proper washing is often neglected. Salt crystals can form on particle surfaces during the drying process before electrostatic separation.This paper describes a study that has been conducted to determine the effect of upfront salt water processing on downstream electrostatic/HT separation. The study indicated that minor quantities of salt can cause the separation efficiency to decrease substantially.

Oct 5, 2011

The Yilgarn Block of Western Australia presents (figure 1) a number of problems for conventional diamond exploration based on heavy indicator mineral sampling. These problems are due to the geology and unique geomorphological development of the Yilgarn Block.Essentially the Yilgarn Block is a pene- plain developed on a craton composed of Archaean intrusive granitoid rocks with meta- morphosed greenstone; which, apart from regional uplift, has not been tectonically disturbed since planation by glaciation in the Permian. Therefore since the early Plesozoic the Yilgarn Block has been subjected to terres- trial weathering conditions. Bettany et al., (1984) identify two phases of particular importance in the development of the present landforms: 1. Periods of lateritization during the Tertiary which result in the ~lassi~al laterite profile (figure 2). Duricrust indurated : Fe and Al oxides Mottled zone : Clay and Fe oxides Saprolite or pallid zone : leached clay grading into fresh rock. 2. Subsequent periods of aridity and semi- aridity during which laterite development was truncated and reworking of laterite Occurred.

Jan 1, 1988

It should be noted that with the passage of time all aspects of the mineral extraction process are becoming more sophisticated and complex. In order to deal with this, the education system should be geared to this continual technological advance.A new scheme is designed to attract high quality school leaven to take up courses serving the mineral industry. After graduation these students will play an important role in the areas of research and development which is essential for the growth of the Australian mining industry.

Jan 1, 1991

And it takes more than good organisation. You may read or heard this poignant reflection: We tried hard, but it seemed that every time we were beginning to form up in teams we would be reorganised. I was to learn later in life that we tend to meet any new situation by re-organising, and a wonderful method this is for creating the illusion of progress while producing confusion, inefficiency, and demoralisation This was written by the Roman Gaius Petronius in AD65. How much have things changed in nearly 2,000 years? What then does it take besides the fundamentals and good organisation to build a successful career in a successful organisation? I'm prepared to venture a list of what I'll'call Tips for Young Professionals. If you've got what it takes, and apply these, I think that you'll gain a great deal of satisfaction from your career, even if you don't reach the distant target each of you should have in mind now. So settle back in an advice-receiving mode, and please forgive me if I come across as a master of the bleedin' obvious, as Basil once accused his wife Sybil of being in the unforgettable Fawlty Towers.

Jan 1, 1990

Someone once said "Leadership is the ability to inflict pain and get away with it." The same can be said about successful management of equipment suppliers. Improved performance will not be achieved without some pain, but it should be evenly spread between both parties. In practically all mining situations there is a great deal of scope for improving performance and reducing maintenance costs on an extremely wide range of plant, but it requires co-operative effort. Most mine maintenance engineers attribute the main problems to the equipment suppliers, unsuitable designs, lack of spares, untrained servicemen, lack of standardisation, poor maintenance manuals, and so on. Conversely the suppliers' engineers are usually convinced that problems with their product are exclusively due to poor maintenance management, after all they never have the same problem elsewhere. Of course both are correct to some degree. My aim in this paper is to explore the opportunities for substituting collaboration for confrontation between the engineers of the mining and supplying companies. I will also propose that contrary to common belief, the mines rather than the suppliers, should be taking the management initiative needed to achieve a closer and more effective relationship, Many would argue that this initiative should remain solely with the supplier; after

Jan 1, 1980

By A Harburg, A Dendys, G Green

Dugald River Mine (DRM) is located approximately 85 km north-east of Mount Isa, and 65 km northwest of Cloncurry, in the north-west Queensland Minerals Province of Australia. DRM is an underground operation and includes an above ground processing area, a 200 ha tailings facility, two waste rock dumps and associated infrastructure. The mining method is conventional underground longhole open stoping and downhole benching of a lead/zinc deposit within a black slate environment. The deposit is estimated to contain ~53 Mt of zinc and lead, which will be mined over a 30-year period. During operations, waste rock is segregated into either Potentially Acid Forming (PAF) or Non-Acid Forming (NAF) based primarily on the sulfide concentration of the rock. In particular, the NAF waste rock is an asset and is used for various small construction projects during operation; however, its primary use is for rehabilitation work at closure. Since beginning operations in 2017, DRM has generated more NAF than was originally anticipated. Whilst this is an excellent asset to DRM, it did pose a logistical problem of where to store the additional NAF for the life-of-mine and how to manage the run-off. DRM experiences distinct wet and dry seasons with hot conditions and periods of rainfall between November to April, and relatively dry and mild conditions between May to October. Majority of rainfall is received between January and February with an annual average rainfall of 501.1 mm. Short and intense rainfall events are common. DRM’s above ground infrastructure is land-locked between two large ephemeral watercourses, making the significant expansion of any assets challenging from a permitting/regulation and cost perspective. MMG is also a member of the International Council on Mining and Metals (ICMM) and is committed to adapting to a changing climate through operations and closure. Following extensive studies DRM opted to store the additional NAF material into the adjoining NAF Dam and concurrently upgrade a previously minor sediment basin into a highly engineered sediment basin which relies on automatic flocculant dosing to meet the required discharge quality limits. This basin is climate-resilient in that the dosing system can be adjusted to counter high intensity extended rainfall events which produce highly variable inflow water quality. This abstract broadly describes how DRM designed and implemented an engineering innovation to enable the site to meet the changing climatic challenges. The abstract then describes the process to design the sediment basin and how the dosing rate was established and validated. Finally, the abstract comments on the effectiveness of the sediment basin and how it has revolutionised DRM’s approach to water treatment and management; all whilst minimising the disturbance footprint of the operation

Aug 2, 2023

By B Wong, R G. Coleman

In flotation, the selection of the size, number and type of cell for a particular duty depends on two important factors. Firstly, the required flotation residence time and secondly, the physical constraints of how much concentrate can be recovered for a given froth surface area and concentrate lip length. The residence time is influenced by ore type and characteristics such as liberation, kinetics and reagent dosage. The amount of concentrate that can be recovered for a given froth surface area and lip length depends on ore type and other characteristics such as particle size, specific gravity and mineral grade. Residence time is determined through a combination of laboratory-scale test work and design scale-up factors. However the critical froth transport parameters such as froth carry rate and froth lip loading cannot be determined in a laboratory. This is because the froth is scraped during a laboratory flotation test and thus does not exhibit natural behaviour, and it is not possible to scale-up froth transport distance or air rate. These values are generally compared via calculation to rule-of-thumb maximum values to establish if these values will be exceeded by the flotation cell selection.This paper first reviews these critical froth transport parameters and then discusses actual parameter values across diverse operating sites, with varying cell duties, cell sizes and types, orebodies and particle sizes. These values are compared against the industry rule-of-thumb to test the applicability of the rule-of-thumb to actual performance. Options are also presented for adjusting these parameters in operating flotation cells.CITATION:Coleman, R G and Wong, B, 2018. Flotation launder design and the measurement of critical froth transport parameters, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 353–362 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018