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A methodology for the fatigue life estimation of load haul dumpers, employed in underground platinum mines, has been developed and applied. This method entails the quantification of operating conditions by means of stress measurements. The measurements are then translated into a fatigue loading factor for a finite element model. The results of this analysis are then used to compare all the critical connections in the structure to detail categories in relevant fatigue codes, and predict a life in operating hours for the vehicle structure. The method was applied on a specific model and the results of this analysis were compared to actual failure occurrences with reasonable accuracy. It is intended that the methodology be embedded into performance specifications and purchasing contracts and that technology transfer to OEMs be achieved. Based on the experience of this project and other similar exercises it is estimated that structural life expectancies may be increased across a typical fleet of trackless mining vehicles (LHDs, drill rigs, utility vehicles, dump trucks) by at least 20 per cent.

Jan 1, 2005

By J Vann

The key functions of project evaluation are to assess potential profitability and to develop an effective operational design. For mining projects, design aspects include mining methodology, ore treatment methodology and production rates. All of these characteristics impact on project economics and overall value. Resource models, which form the ultimate basis of project evaluation, typically consist of tonnes above cut-off, grade above cut-off and the spatial distribution (connectivity) of tonnes/grade above cut-off, for one or more variables. Dilution, ore loss and metallurgical recovery are all modifying factors applied to the resource model during evaluation and determination of profitability. A key issue is: how is the value determined? In addition to traditional combination of in situ tonnes/grade, the following merit serious consideration: the concentration of deleterious elements, throughput rates, mining/processing costs and û importantly û metallurgical recovery. Geometallurgy is an emerging field targeted at integrating these issues by identifying either direct measures or proxies for throughput (hardness, grindability), recovery (liberation, mineral shape/texture, etc) and concentrate quality from easily collected macro-, meso- and microscopic data. These ægeometallurgical variablesÆ drive project costs and revenues in a fundamental way. For geometallurgical characterisation to have a real impact on business design, it must enable improved mine planning. When creating spatial estimates for such variables, it is preferable to find proxies that can be measured as close to the intact rock mass as possible. However, spatial estimation of proxies for geometallurgical properties and responses is complex and requires special consideration. Unlike grades, both proxies and absolute measures of geometallurgical variables are not necessarily linear or additive and therefore require very careful geostatistical consideration. In some cases, models must predict extreme values of geometallurgical attributes rather than averages. Incorrect characterisation of metallurgical recovery/throughput can (and has) led to misspecification of the scale of projects, and thus can be seriously value destructive. Aspects of geometallurgy have long been important in iron, bauxite, manganese and coal deposits and are increasingly on the radar for base and precious metal miners. However, as more metallurgically complex deposits are developed and mining of large-scale, low-grade deposits becomes more commonplace, the importance of characterising the metallurgical response in order to generate properly optimised projects will rapidly increase. It is possible that in many ætraditionalÆ (ie grades and tonnes) reserve models, the variables that drive the project are missing!

Jan 1, 2007

By Mercer JK

This paper gives a description of the research undertaken by an explosives manufacturer to give better technical advice to the Mineral Industry. Blasting Physics is defined as giving a systematic and coherent account of the initiation and subsequent effects of high explosives upon the surrounding medium. As a result of this work a mathematical model based on the gener- ally accepted mechanism of blasting has been developed. The mechanism and the resulting model are briefly outlined. IFrom'this model the effects of burden, spacing, blasthole diameter, rock and explosive properties upon fragmentation and heave can be calculated. Using these calculations it is then possible to see how variations in frag Imentation and heave can affect the overall production costs of a mine whether it is surface or underground. The overall costs are made up of a number of individual costs - drilling, blasting, loading, hauling and crushing. ach of these operations influences or is influenced by fragmentation and heave s these costs are inter-related, the

Jan 1, 1975

The treatment plant of the Gold Mines of Kalgoorlie Ltd. is situated on the Oroya South Lease, on the Eastern edge of the Kalgoorlie Golden Mile.It was designed and erected by Messrs. Alex. Stewart and Company, in consultation with Mr. Harry Hey, and was completed in November, 1937.Its original capacity was 9,000 tons of all-sulphide ore per calendar month, l?ut the plant was extended in October, 1939, to treat 13,000 to 14,000 tons per month of mixed sulphide and oxidised ore.Recovery of the gold is accomplished by cyanide treatment, followed by flotation of the cyanided residue, roasting and cyanidation of flotation concentrate and precipitation of the gold from the cyanide solutions. In the cyanide section, the crushed ore is finely ground in cyanide ,solution and the pulp is agitated to dissolve further gold. It is then thickened and filtered. In the flotation section, this filter residue is conditioned with S02 gas and a pyrite-gold concentrate recovered by flotation.This concentrate is roasted and then cyanided.KALGOORLIE ORE DEPOSIT.The Kalgoorlie ore deposit occurs within a wide area of Pre-Cambrian rocks, ,and consists essentially of two series of basic igneous rocks known as the older greenstone series (calc schist) and the younger greenstone series (quartzdolerite- greenstone) . The older greenstone is a group of lava flows. The younger intrusive greenstone series can, in the main, be classified as a chloritised and carbonated...

Jan 1, 1948

By B Dunstan, F Wirfiyata

PT Newmont Nusa Tenggara (PTNNT) operates the Batu Hijau copper and gold mine and process plant on the island of Sumbawa, Nusa Tenggara (Barat)  NTB, Indonesia. The plant consists of a nominal capacity 120 000 t/d conventional semi-autogenous ball milling crushing (SABC) circuit followed by sulfide flotation to produce a bulk copper concentrate for sale. Process control is effected by a plant wide distributed control system that overlays an extensive integrated programable logic controller (PLC) framework. The system is enhanced by a supervisory expert control system.Since plant commissioning in September 1999, over US$4 million has been expended as part of a systematic continuous improvement approach to optimise plant control performance. Works completed to date include: redesign and upgrade of architecture of the control system to ensure long-term system reliability, security and upgradeability and to provide a suitable platform for advanced control; integration of supervisory and advanced control tools, techniques and instrumentation; and implementation of sound network communication and plant data reporting tools. This paper outlines the evolution of process control and associated systems and tools that contribute to successful operation and ongoing performance optimisation at Batu Hijau.

Jan 1, 2009

By Orr T. O H, Hodkinson I. P

The Mount Leyshon breccia complex is located on an east-west trending contact between Cambrian metasediments (Puddler Creek Formation) and the Ordovician Mt. Leyshon granite, within the Lolworth-Ravenswood block. Detailed mapping of basement, breccia and igneous unit geometries, crosscutting relationships and resolution of complex chronological relation- ships indicates that the Mt. Leyshon breccia complex should be reinterpreted as a number of intrusive igneous and breccia phases. This is in contrast to a previously published account of a largely extrusive geological setting. A complex structural history dominated by strike-slip faulting is preserved within the basement units and is responsible for controlling the location and geometry of the breccia complex. The breccia complex has been divided into brecciated "basement", "main pipe breccia" and an "interactive magma/breccia sequence". Main pipe breccia (the most voluminous unit within the complex) has been re-interpreted as an intrusive breccia, rather than an extrusive or vent fill as previously proposed. This is based on the following evidence: 1. the facies characteristics of the main pipe breccia, 2. the presence of a progression from cohesive basement through to mixed breccia, 3. minor basement block rotation during breccia complex formation, and 4. the partial structural control on the main pipe breccia. No unambiguous evidence exists for pyroclastic facies, although the fine breccia variant commonly contains "accretionary structures", very similar in appearance to those formed during pyroclastic processes. In view of 1. above, they are interpreted to be the product of particle accretion during upward movement of fragmental material, although an origin due to altera- tion cannot be completely discounted. heir occurrence in the main pipe breccia indicates that their presence within a rock unit is not necessarily diagnostic of nvroclastic nroeesses.

Jan 1, 1991

Magmatism is of first order significance in the extension process. Continental extension is terminated when sea-floor spreading commences, but sea-floor spreading will not commence if magmas do not begin to arrive in sufficient volumes. In the oceanic lithosphere, the rate of magma supply may determine whether sea-floor spreading takes place, or lithospheric extension as the result of normal fault arrays. In continental crust thickened as the result of previous compressional orogeny, the availability of magma may determine a completely different process. The author has examined metamorphic core complexes in a number of tectonic environments, in the North American Cordillera, in the Aegean Sea, Greece, and in the Solomon Sea, Papua and New Guinea. What these terrains have in common is a major collisional orogeny predating a major extensional event. The "roll back" of the lithospheric flexure associated with subduction can be seen as the "driving force" for extension in two of these cases. Metamorphic core complexes in these environments are characterized by domal exposures of crustal scale ductile shear zones, underneath which massive plutonic complexes have been formed. Emplacement of these plutons is associated with anatexis of the surrounding rocks. Migmatite complexes are well developed in the Aegean and Solomon Sea core complexes, and in some core complexes in the Basin and Range. Chains of core complexes can be explained as the result of basaltic and andesitic magmas derived from a linear belt of relatively hot rising asthenosphere, in a zone of attempted continental "break up". It is argued that core complexes are the results of magmas derived from relatively short lived mantle "hot spots" impingeing on extending continental crust which has been overthickened during previous compressional orogeny.

Jan 1, 1990

By Turner T. M

The problem of metering fine particulate material at low flowrate is often encountered in metallurgical experiment. This note describes a feeder which wa developed to provide metered flows of copper sulphide concentrate in the range of 0'1-0'7 g/min.It is believed that the present device is easier to operate than previously described feeders (e.g. Hamor and Smith, 1971). It may have applications in the field of analytical chemistry, as well as in metallurgical investigations.

Jan 1, 1978

By P Barrette

The manual gravimetric drying moisture determination methods currently employed by most mineral processing plants fail to provide timely and accurate information required for automatic control. The costs associated with transporting and handling concentrates represent a major portion of the overall treatment price. When considering the cash flow of a mining operation that is governed by both the smelter contract, with moisture penalties and the quantity and quality of the concentrates shipped, any tool that provides real-time feedback on the process is vital (Edwards, RP 1994). The introduction of an on-line moisture sensor would become a welcome addition to the process control field instrumentation package now applied. A novel on-line determination system for ore concentrate moisture content would replace the tedious manual procedure. Since the introduction of microelectronic-based control systems, operators have strived to reduce the treatment costs to the minimum. Therefore a representative and timely determination of on-line moisture content becomes vital for control set points and timely feedback. Reliable sensors have long been on the æwish listÆ of mineral processors since the problem has always been that you can only control what you can measure, (Konigsmann, 1990). Today, the task of moisture determination is still done by the classical technique of loss in weight utilising uncontrolled procedures. These same methods were introduced in the earliest base metal concentrators. Generally, it is acceptable to have ore concentrate moisture content vary within a range of seven to nine percent, but controlling the moisture content below eight percent is a difficult task with a manually controlled system. Many times, delays in manually achieving reliable feedback of the moisture content results in the moisture varying from five to twelve percent before corrective actions can be made. This paper first reviews the traditional and widely available methods for determining moisture content in granular materials by applying physical principals and properties to measure moisture content. All methods are in some form affected when employed on mineral ore concentrates. This paper introduces and describes a unique and promising novel on-line moisture sensor employed for mineral processing de-watering applications, which not only automates the tedious tasks but also results in reliable moisture feedback that can be used in the optimisation of the de-watering process equipment such as pressure or vacuum filters and fuel-fired driers. Finally, two measurement applications will be presented to indicate the usefulness and to summarise the measurement requirements for the proposed method of employing drag force and mechanical properties of the material itself to determine the moisture content. The commercial model of the equipment is described with the features and benefits to the users summarised.

Jan 1, 2003

The major greenhouse gas emissions from coal combustion are leading certain people to argue for uranium mining and nuclear power to meet these challenges. Although there is considerable rhetoric around promoting nuclear power as 'green' due to its relatively lower greenhouse intensity, a careful study of the data is required to properly underst and the sustainability of uranium mining and nuclear power and whether it can or should have a role in future energy supply scenarios. This paper presents detailed research and analysis on uranium mining, focusing on known economic resources, production, solid waste and water management, pollution issues as well as energy and greenhouse aspects. A particular focus will be on Australia and its operating and prospective uranium mines. Overall, the paper raises fundamental issues concerning the long-term sustainability of uranium mining and nuclear power and documents the greenhouse intensity of uranium production and the nuclear fuel chain.

Jun 1, 2010

By Schneider CL

The calculation of the liberation spectrum in the product from continuous milling operations is a problem of considerable importance, and it is difficult to solve because the population balance equation must be integrated in two-dimensional space. Complete solutions require a very detailed knowledge of the complex interactions between the fracture patterns and the mineralogical ore texture when brittle particles are subject to impact fracture. Most of the liberation models that have been developed to date apply only to batch comminution processes and under these conditions the liberation problem can be studied in isolation. When the comminution is continuous and forms a unit operation in a flowsheet that includes classification and separation operations, the situation is very different, and then the liberation of the minerals must be described when single particles of known mineralogical composition are fractured. Important industrial examples are conventional milling circuits closed by hydrocyclone and regrind mills in flotation plants. This paper presents an efficient computational algorithm for the calculation of the liberation spectrum produced by continuous milling operations. The algorithm relies heavily on the detailed internal structure of the Andrews-Mika diagram. The modifications that are required to make this diagram apply to practical ore minerals, and the internal structure of this diagram can be established using single-particle fracture on mono-size, mono-grade material but suitable liberation models are essential to interpret the data in terms of the cross transfer coefficients required for the population balance procedure. Models proposed by Leroux (1992) and King (1990) are compared to experimental data.

Jan 1, 1993

In the new refinery, at the works of the Broken Hill Associated Smelters Proprietary Limited, situated at Port Pirie, South Australia, the refining routine is similar to that carried on in the old one in that bullion is progressively refined first for arsenic and antimony, then for copper and gold, then for silver, and finally for zinc. However, actual procedure differs in that each refining operation is now conducted continuously, whereas in the old refinery intermittent batch treatment was practised.The early experimental work was concerned solely with the development of the continuous desilverising process, which, in addition to continuous treatment, embraces the novel feature of conjugate solution formation with consequent production of a silver product relatively high in silver and low in lead.

Jan 1, 1932

Perhaps no aspect of the investigation of an ore-deposit is of greater importance to the mining geologist and engineer than a consideration of its geological structure. A thorough understanding of the type, size, shape, and arrangement of any ore-body is essential to the proper conduct of exploratory, developmental, and mining, operations. Significant as these remarks are' in relationship to ore-deposits in general, they become of paramount moment when a complex structure such as the Broken Hill Lode is in question. In this connection the use of the term "lode" as applied to the Broken Hill ore-bodies may terid to confusion of ideas among those not familiar with the field or with the literature pertaining thereto, by reason of the fact that it is generally understood that a "lode" is characterised by simple, tabular form, regular outline, defined walls, and persistent attitude. However, as the terminology is well established by common usage, itsretention appears desirable, and, for the purpose of this paper, the name "The Broken Hill Lode" refers to that complex unit which includes pre-eminently the famous ore-bodies exposed in the workings from the North Mine on the one extreme to the South Blocks (Zinc Corporation) Mine on the other.That the practical value of geological investigation, of the ore-bodies was realised by the Geological Sub-Committee of the late Scientific Society of Broken Hill is attested by the...

Jan 1, 1932

By Mike Sharwood

This subject is to be discussed in greater depth by Mike Sharwood. It has also been the subject of a mini-symposium by the Melbourne Branch of the AusIMM in October, 1993. The papers from this symposium were distributed to the membership late last year "to raise their consciousness and to promote greater awareness and understanding of the wide range of liabilities that may arise". An introductory paper by Nicholson outlined the many areas in which liability may arise with particular emphasis on expert reports, eg: Takeovers Schemes of arrangement Acquisitions from associates Prospectuses Related party transactions Directors' duties Continuous disclosure Other influences (environmental, occupational health and safety, trade practices)

Jan 1, 1994

By M Ewart

The securing of a reliable water supply for a prospective mine in the North West Queensland Mineral Province is usually one of the most influential factors in determining the mine's feasibility. The Ernest Henry Mine required a reliable water supply to serve a demand estimated at feasibility stage to be up to 20 ML/day. Numerous options were considered before a decision was made to construct a 113 km long pipeline from Lake Julius as this was the most cost effective, reliable source of supply. The North West Queensland Water Pipeline is a multi-user, Queensland government funded project initially supplying up to 7000 ML/year of water from Lake Julius to Ernest Henry Mine, with provision made for expansion to serve future users in the region. This paper discusses the history of the pipelineÆs development, together with a summary of the scheme's design features. Environmental and licensing requirements, construction and operational issues are also discussed.

Jan 1, 1998

By F R. M Pires, Y Hasui, A Schrank

The iron ores of Alegria mine are composed of itabirites enclosing minor bodies of high-grade ores. The itabirites are classified according to mineralogical composition in five types: martite-rich, goethite-rich, specularite-rich, magnetite-rich and anphibolite-rich ores. The hematites are martite-rich, magnetite-rich, specularite-rich and more rarely, amphibolite-rich. Other classification criteria of the ores are based on the physical properties and the degree of compaction. As such, the itabirites and hematites can be classified as hard, friable and soft types. The mineralogical/textural evolution of the ores is linked to the pressure and temperature conditions that accompanied the tectonic processes in anphibolite facies and the different degrees of subsequent surficial weathering processes. Petrographic and microstructural studies indicate that the magnetite and amphibole bearing itabirites represent the parent rocks that created the other itabirites and that the specularite itabirites and the hard martite types are related to silica dissolution and redeposition in zones of high and low strain. Most of itabirites ores correspond to chert oxide facies banded iron formation, except the goethite and amphibole bearing itabirite that resemble a silicate or oxide-silicate facies with minor carbonate impurities. The great mass and pods of soft martite itabirites are probably shaley oxide facies BIFs with little volcanic contribution. Trace element contents of the AlegriaÆs itabirites show strong dissimilarities with BIFs associated with volcanism (Algoma type), but closely ressemble to the Lake Superior type, with high content in Cr, Co and low V, Ni, Cu and Zn. Although the absolute contents of REE present in the AlegriaÆs itabirites are, in general very low, the pattern when normalised by NASC is similar to the great majority of the Archean and Paleoproterozoic BIFs elsewhere in the world, and characterised by positive Eu anomaly.

Jan 1, 2002

Most of the gold reef mined today in South Africa is approximately 1 m in width with slopes about 30 m long. To prevent production interruptions it is essential that the stopes should not be blasted in sections. The shortage of experienced labour and arduous working conditions at the face dictate the need for simple blasting techniques.Hence, a pyrotechnic blasting system of sequential firing is in use at present, although research work to improve this technique is in progress.

Jan 1, 1985

By O Aydan, K Sugiura, A Sakamoto

It is well known that some sinkholes or subsidence take place from time to time in the areas where abandoned room and pillar type mines exist. The authors have been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region and there is a great concern about the stability of these abandoned mines during large earthquakes as well as in long term. The 2003 Miyagi Hokubu and 2011 Great East Japan earthquakes caused great damage to abandoned mines and resulted in many collapses. Particularly the effect of the quality of backfilling of abandoned mine below the urbanized areas is very important under static and dynamic conditions. The authors present the effect of the quality of backfilling on the ground subsidence associated with abandoned lignite mines under static and dynamic conditions and discuss its implications on the urbanized areas above abandoned lignite mines in this study. CITATION:Aydan, O, Sugiura, K and Sakamoto, A, 2018. The quality of backfilling of abandoned lignite mines on ground settlement under static and dynamic conditions, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 134–141 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By R Lurf, C Weber

In the frame of this paper a holistic dynamic process model approach is presented in order to introduce operational and technical excellence in drilling and blasting. Both on a macro and micro level the single process parts of drilling and blasting are outlined and their interaction is explained. The use of this approach for closing the gap between process planning and process implementation is explained and an example of the value generated is given.

Jan 1, 2007

By R Frew, E Wong, G Ferguson

The Chang Jiang Tunnel and Bridge Project, when completed, will provide a fixed link between ShanghaiÆs rapidly developing Pudong District and Chong Ming Island, situated in the Yangtze River delta. The link includes 7.5 km of bored tunnel from the Pudong to the intermediate Changxing Island from where the link comprises viaduct and a cable stayed bridge. The bored section comprises twin 13.7 m internal diameter segmentally lined three-lane highway tunnels. At its deepest point the tunnel will be 55 m below the river. Cross passages will link the two bores for passenger evacuation. Tunnel boring commenced in October 2006 and is scheduled for completion in mid-2009. The paper describes the key features of the design and construction of the bored tunnel by two 14.53 m diameter slurry TBMs and eight cross passages using ground freezing techniques in alluvial sediments. A decision to include light rail below the road deck was taken after the completion of the detailed design. This posed a number of design challenges including passenger evacuation to the road deck, and the redesign of the low point sumps. The various options considered are discussed together with those adopted for construction.

Jan 1, 2008