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Aberfoyle sought to reduce Hellyer project development risk to a greater degree than usual. Consequently the ore reserves estimate and feasibility study were particularly comprehensive. A detailed ore reserve study was completed based on extensive drill core and underground sampling, large scale pilot plant work and a detailed feasibility study. Leading external consultants were used for advice on commercial matters which impact on ore reserves and to audit major technical conclusions, including the results from pilot plant work and the ore reserve estimate. Other project risks were diminished by negotiating a State agreement covering security of title, royalty formula and environmental management procedures, by obtaining sales contracts, and by analysing Hellyer's position on an industry cost curve. The task of financing the project was much simplified by the extent and quality of information available from the ore reserves estimate and feasibility study report.

Jan 1, 1990

By P Vix

A thermodynamic model of the copper Peirce-Smith (P-S) converter has been developed to predict the behaviour of magnetite in the converter slag, the amounts of slag and matte, the compositions of slag and matte, the volume of the bath, the bath temperature and the SEMTECH OPC signals. The predictions of bath temperature, slag and matte compositions and magnetite content in the slag have been validated by the industrial data. The effects of fluxing strategy, returns and skim charges, oxygen enrichment and temperature on the magnetite formation in the slag have been predicted and discussed. Some industrial applications of this model have been presented.

Jan 1, 2005

By M Thompson

"The Jaguar concentrator, 60 km north of Leonora, Western Australia (WA), consists of a standard closed circuit semi-autogenous grinding (SAG) and ball mill producing a float feed of approximately 60 micron at 70 t/h. Following comminution, separate copper and zinc concentrates are produced by differential flotation. These concentrates are subsequently dewatered by thickening and then filtration.Separate audits of the Jaguar Operation’s copper and zinc concentrate thickeners were conducted to evaluate their performance, following occasions where site personnel had identified unnecessary loss of copper and zinc concentrate to the thickener overflow. The feedwells were identified as the source of the observed problems due to the following issues with their design/duty:lack of retention time in the feedwell as current design is completely opennot conducive to effective mixing required for efficient flocculationdiameter of the zinc concentrate thickener feedwell was undersize for its duty.To improve the performance of the thickeners, it is planned to replace both concentrate thickener feedwells with a high rate design for their respective duties in February 2016. The audits also identified that the feed system requires modifications with particular importance placed on minimising air entrainment of slurry into the thickener feedwell. Minimisation of air entrainment is hoped to be achieved by providing constant head pressure through installation of weir arrangements in the feedboxes and redirecting each feed pipe so that it feeds tangentially into the feedwell. In addition, improvements to the control philosophy of both thickeners will be made with the installation of an ultrasonic bed level probe and bed mass sensor, in order to make real-time adjustments to the underflow pump speed to maintain steady state operation.Following the feedwell replacement and modifications to both thickeners it is expected that losses of recovered copper and zinc will decrease to undetectable levels. Subsequently it is anticipated that a more consistent, homogenous underflow can be produced for downstream filtration.Citation:Thompson, M, 2016. Concentrate Thickeners Feedwell Replacement, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 273–278 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

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 R R. Large

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The formation of orogenic gold deposits is commonly a two-stage process. The first stage involves preconcentration of gold in a suitable source rock, such as carbonaceous black shales, felsic volcaniclastics or komatiitic volcanics. The second stage involves the release of gold (commonly with arsenic and/or tellurium) from the source rocks during metamorphism or magmatic intrusive events, accompanied by the replacement of source rock pyrite by pyrrhotite. Recent research suggests that synsedimentary gold trapped in the structure of diagenetic arsenian pyrite in reduced carbonaceous facies of continental margin sedimentary basins is an ideal source of gold for many orogenic and Carlin-style gold deposits. The conversion of diagenetic arsenian pyrite to pyrrhotite during basin closure and greenschist facies metamorphism is the key process releasing gold and arsenic to the metamorphic fluid, with metal deposition in structural trap sites to form the deposits.CITATION:Large, R R, 2015. Orogenic gold deposits – a two-stage process of gold enrichment, in Proceedings PACRIM 2015 Congress, pp 335–340 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Past and present developments in the use of blast furnace slag in the manufacture of glass are outlined. The crude slag from Port Kembla is beneficiated by the Mineral Resources Division of Australian Consolidated Industries Ltd. at Mascot using a dry magnetic separation process which reduces the iron level in the slag to an acceptable value, The chemical and physical properties of both the crude and beneficiated slag are given and compared with those of other slags used in the manufacture of glass. Slag is added to intro- duce alumina into the glass and its addition to the glass batch also results in faster melting and refining. Slag was first used in Australia in 1968 and its use has increased steadily year by year. At present about 16 000 tonnes of slag are used per year, mainly in amber and white glass. Beneficiated slag is used'in three plants to supply all the alumina required in the amber glass and in four plants to supply part of the alumina required in the white glass, the amount added depending on the acceptable iron level in the glass. Slag is also used in limited quantities in the manufacture of both dark and light green glass.

Jan 1, 1979

By Lee H. G, El-Rahaiby S. K

The literature relating to reduction of sulphides by carbon using lime as sulphur-absorbent is reviewed. A stage-wise thermodynamic model is employed to evaluate the practical feasibility of the direct reduction smelting of galena (PbS) concentrates with a carbon reductant in the presence of lime; a coke-rate of 65 kg/ton Pb is predicted by the model. The experimental data on the reduction of PbS:4CaO:4C mixtures under nitrogen were correlated by means of a finite difference numerical method and the values of the intrinsic rate constant I1 were derived. The results for the uncatalysed reduction are represented satisfactorily with log I1 = 1.247(±0.522) - 5540(±610)T-1.The catalysed PbS:4CaO:4C mixtures contained 2.5 wt% of ternary (K, Li, Na)2CO3 catalyst. For the catalysed reduction it was found that log I1 = 3.981 (±0.301) -7790(±353)T-1, where I1 (in both relations) is expressed in moles.(g.C.)-1.atm-1.s -I. The catalytic enhancement faclor was found to be quite large in the 1068 to 1262°K temperature range investigated here.

Jan 1, 1991

The Henty Gold Mine is a good example of a situation where conditional simulation and optimisation techniques may have useful impact on modelling of mineralisation distribution and ore definition. Much of the gold mineralisation at Henty is concentrated within an alteration zone which is both physically discontinuous and forms only a small fraction of the overall mineralised volume. The alteration units are mappable from diamond drill core and underground workings. Conditional simulation and optimisation techniques for ore definition have found considerable success in the open pit gold mining environment. For many reasons including computational efficiency, lack of consistent geological information, and lack of familiarity with ideas and methods among mine geologists, implementations of these methods in open pit mining have been comparatively simplistic. Modelling is commonly reduced to treating the sample data as a single geologic population. This paper discusses the application of the MP method (a particular implementation of conditional simulation and optimisation) to modelling the distribution of potential ore blocks in the Henty gold mineralisation. The approach allows the mine geologist to model both the spatial geometry of the alteration types and the gold grades associated with each alteration type in a single process. Options allow the geologist to include or exclude underground geological mapping and face sampling depending mainly on the abundance of drill hole sampling and the quality of the face sampling. An optimisation algorithm based on maximisation of profit from mining is used to assist in ore definition.

Jan 1, 2000

Following the Moura No 2 Wardens Court of Inquiry and subsequent changes to the Queensland Mining Legislation there is a requirement in Queensland coal mines for: a person with the recognised competencies to be appointed at each underground coal mine to the position Ventilation Officer; and the person is directly responsible for the implementation of the mine ventilation system and for the establishment of effective standards of ventilation for the mine. The Regulations require that an underground mine must have principal hazard management plans that provide for at the least the following: emergency response, gas management, methane drainage, mine ventilation, spontaneous combustion, and strata control. Other than strata control all the plans require the ventilation officer to have roles and responsibilities to develop, control, monitor and undertake actions in relation to these plans.There are also another 34 Regulations that either directly or indirectly requires the Ventilation Officer to take actions.The purpose of this paper is to outline the information that the regulators look for in sealing plans and the actions the regulators will take if the sealing does not go to plan (TARPs being exceeded).

Jan 1, 2005

By D Judkins N OÆLoughlin

"Basin Minerals Limited commenced exploring for conventional strandline hosted mineral sands (rutile, ilmenite and zircon) deposits in the Murray Basin in April 1997. This has resulted in the discovery of a major mineral sands field in the Douglas Project area, located southwest of Horsham in the Wimmera Region of Western Victoria. After the successful completion of a pre-feasibility study on these deposits in September 2000, the Douglas Project has advanced to bankable final feasibility study. This study should be completed by mid-2002 to allow a decision to commence production in 2003 at an expected rate of in excess of 500 000 tonnes of combined mineral sands products per annum. The field comprises several mineralised strandlines. The main ones of economic interest are from west to east, the four strandlines, Acapulco, Bondi, Bondi East and Echo. These strandlines at August, 2000 contain total Inferred Resources of 443 million tonnes at 4.7 per cent HM at a one per cent HM cut-off; ie 20.8 million tonnes of heavy mineral concentrate which in turn contains 11.3 million tonnes of ilmenite and leucoxene, 1.3 million tonnes of rutile and 1.6 million tonnes of zircon. The heavy mineral concentrate is coarse-grained with mean diameter grain size of the strandline deposits ranging from 130 to 160 microns in size. Major controls on the formation of mineral sands deposits in the Murray Basin are discussed with reference to the main mineral sand bearing, strand plain domains; the Central Strand Plain, the New South Wales Strand Plain and the West Wimmera Strand Plain. The Douglas Project deposits on the West Wimmera Strand Plain domain are characterised by wide zones of mineralisation with high-grade cores (>10 per cent HM), low stripping ratios, and a valuable economic heavy mineral suite comprising 60 to 80 per cent of heavy mineral concentrate. Constituent mineralogy of the heavy mineral concentrate of the overall deposits is; ilmenite (40 to 58 per cent), leucoxene (five to seven per cent), rutile (four to ten per cent) and zircon (four to 14 per cent). The Douglas Project Area appears to be endowed with significantly enhanced levels of heavy minerals compared to other areas of the Murray Basin due to its unique palaeo-geographical position. Long shore drift to the south of the basin has caused large quantities of heavy mineral to be trapped against the palaeo-cliffs and headlands of a rugged palaeo-coastline which includes in a major embayment, the Grampian Mountains, the Black Range and the Glenelg Complex. To the east, major faulting and uplift has brought the fine-grained WIM offshore deposits close to the surface and has resulted in erosional stripping of mineralised strandline deposits. This mineralisation has been recycled and reconcentrated within the younger strandlines to the west within the adjacent Douglas Project Area. These strandlines are thought to be younger than other mineralised strandlines discovered to-date in the Murray Basin. The Project Area strandlines are described; ie their morphology, geology and patterns of mineral distribution. The mineralogy of each of the strandlines is distinctive and variations are noted along strike and section."

Jan 1, 2001

The GDR has extensive lignite deposits at its disposal, which formed the basis for the development of an independent energy source after 1945 and which will retain their significance well beyond the year 2000 (see fig. 1). In 1946 lignite output was about 110 x 106 t. In 1985 312x 106 t was produced and in 1988 the planned output will be ca. 315 x 106 t. Thus, the domestic produc- tion of lignite covers ca. 75% of the GDR's primary energy requirements. More than 80% of the electrical energy is gener- ated by the use of lignite and about 12% by nuclear energy. In addition to this, about 18 x 106 t/a mineral oil and about 6 x 109, m3/a natural gas are imported, predominantly from the Soviet Union. The lignite deposits of the GDR are of Tertiary origin and are recovered exclusively by opencast mining. There are two large regions (fig. 2): - in the region east of the river Elbe (Cottbus/Senftenberg- "Niederlausitz") and - in the region west of the river Elbe (Halle/Leip- zig/Magdeburg). These deposits differ in geological age and conditions of depo- sition, consequently there are differences in their chemical and physical composition and, thus, in their uses. The younger Mio- cene coals of the main region in the East of the river Elbe belong to the epirogenetic type and have a low content of ash and sul- phur. Among other things, they are suitable for the production of brown coal high-temperature coke (Lauchhammer and Schwarze Pumpe). The older Oligocene coals of the Halle/Leip- zig region are bitumenous in certain areas. Therefore, they form the basis for production in low-temperature carbonizing and chemical plants. In the Halle-Magdeburg region, where the lig- nite is in contact with the underlying Zechstein subdivision, so- called "salt coals" are found.

Jan 1, 1989

In referring to two subjects of interest to the Members of this Australasian Institute of Mining Engineers, I would at the outset desire to express our gratification that to-day we are able to welcome as now united with ourselves, those members who until recently constituted the New Zealand Institute. It is hoped that the amalgamation so amicably arranged may be productive of the best results to all concerned, incorporated as this combination has been at the moment of the fulfilment of that greater political union, the Australian Commonwealth.Since last Annual Meeting held in Brisbane, we have come under the same roof as the Chamber of Mines of Victoria, and we entertain the hope that as that Chamber and this Institute possess so many interests in common in the encouragement and advancement of mining and metallurgical progress in these colonies, that much mutual benefit will ensue. There are many directions in which each body can assist the other, and I trust that a friendly co-operation will be maintained.It is gratifying to feel that in all the colonies a distinct movement is being made to increase the facilities for education in Mining and Metallurgy but if I may refer to our colony of Victoria in particular, we have to express the profound regret that in the means of education in the higher branches, we occupy an inferior position, and it is quite certain that we will continue to do so unless the Government is prepared to subordinate provincial considerations to the weightier.

Jan 1, 1901

By A Calderon, J Harris, M Shi, D Viswanathan, C Ribeiro Duthie, P A. Kirsch

Mineral resource development activities impact the health and well-being of many people, from workers, to families and surrounding communities. In the current environment of corporate social responsibility life-of-mine planning considers that mining activities should be conducted in the best environmentally, socially and economically acceptable way for the entire life of the mine (ie from exploration to decommissioning and closure). In this context, the health impacts of mining extend throughout the life of the community from worker injury and chronic exposure to communicable and non-communicable causes of illness, through to family and community health and well-being. At the inaugural Life-of-Mine conference in July 2012, the authors proposed the life-of-mine in the life-of-community (LOMLOC) matrix as a framework for understanding issues at the interface between resource extraction operations and the surrounding environment.This paper reviews and compares health activities extracted from social and environmental reports published by selected major mining companies with American operations in Canada, Colombia and Brazil. These corporate approaches to public health management are mapped to the LOMLOC matrix to identify and compare trends and behaviour in corporate health investments. This analysis of how companies approach and prioritise health issues in the context of different regions, cultures and environmental drivers will serve as a resource for minerals industry managers, civil society and regulators regarding current health management approaches in this sector.CITATION:Ribeiro Duthie, C, Calderon, A, Viswanathan, D, ?Shi, M, Harris, J and Kirsch, P A, ?2014. Resource company investments in health – a life-of-mine / life-of-community perspective across America, in Proceedings Life-of-Mine 2014 , pp 349–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By Massy-Greene RB

Limited recourse financing techniques reduce the financial exposure of equity holders to major mining projects by transfering some of the risks to the banks which provide loan funds for project development. This can only be achieved by a clear understanding of the principles involved. Engineering and management decisions on how the resource is to be developed and extracted must be made in the light of lender's requirements. The structure of sales contracts, joint venture agreements and many other documents can be important in limited recourse financing. If projections show that the debt can be repaid from project cash flow, loan agreements and other arrangements can restrict lenders ability to look to the equity holders for repayment of project loans.

Jan 1, 1981

After a very brief historical survey and overall assessment of traffic requirements, the invitation by the British and French Governments for private groups to make proposals for a "fixed link" is described, and the resulting plethora of proposals is reviewed. The three schemes which gave some promise of being adequately backed by private finance are described as follows:

Jan 1, 1987

By P A. Grossman, J H. Rubinstein, M Brazil

The installation of truck turntables at above-ground crushers has the potential to yield gains in efficiency and productivity by eliminating the need for the trucks to turn around and reverse up to the crusher to dump their loads. The benefits include savings in time, fuel consumption and tyre wear. In addition, having a smaller area near the crushers dedicated to manoeuvring the trucks can be a significant benefit at some sites. Safety is also enhanced using turntables.This paper describes a project with the Australian Turntable Company to develop software that generates near-optimal layouts for the paths taken by the trucks in the vicinity of the crushers when turntables are present or absent. The geometry of the paths is constrained by the turning radius of the trucks and by the boundary of the manoeuvring area. The software quantifies the benefit of installing turntables by generating a design for paths with turntables and comparing it with the layout in current or planned use by the mining company. Through the use of this software tool, a mining company can readily assess the benefits of using turntables at their site.CITATION:Brazil, M, Grossman, P A, Rubinstein, J H and Thomas, D A, 2014. Demonstrating efficiency gains from installing truck turntables at crushers, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 259–266 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By S Van Duin, I Porter

This paper discusses how advanced manufacturing technology (AMT), which is fundamentally reliant on and developed via multi-disciplinary skills, has benefitted non-mining industries, and what lessons can be derived from this experience to benefit the mining industry, particularly underground coal mining. Examples of AMT use in æconventionalÆ industry, some drawn from the more than 25 years experience in many different industries of the Automation and Robotics team at the University of Wollongong, are described to show typical benefits, risks and opportunities expected in using AMT. Applying AMT to mining brings many unique challenges and this paper expands on these and then provides practical examples of how a multi-disciplinary team can develop new processes and systems leading to productivity, safety and other benefits for underground coal mining.

Sep 26, 2011

By Thompson D, Somerville JM, Brock DA

The development of a softwood alternative to the hardwood chockpiece used to build the waste-edge breakers commonly incorporated in gateroad packs is described. The results of laboratory tests on softwood prototypes and two underground trials are presented. The results of the last trial suggest that a viable alternative chockpiece has been designed, offering advantages over availability of wood, weight and given reduced wood content, price.

Jan 1, 1992

By E Villaescusa

This paper describes a methodology for the design of mine pillars at the McArthur River Mine. The pillar strength is calculated using a method that accounts for confinement, pillar geometry and intact rock properties. The average pillar stress was calculated using in situ measurements of vertical stresses at shallow depth and the tributary area method in conjunction with numerical modelling. Observations of pillar behaviour indicate that an existing pillar stability graph may be slightly conservative and further adjustments for the local rockmass conditions are needed. The results to-date indicate that all mine pillars are stable for a range of mining geometries at McArthur River Mine.

Jan 1, 1998

The mine manager is one of the oldest jobs in the world. Over many centuries the fundamentals of how this job was approached did not change much. However since the later part of the 1980s there has been a dramatic shift in the expectations and role of the mine manager as the pressures of globalisation and consolidation have increased the size of companies and the production levels of mining operations. The changes have been dramatic, with demanding requirements on mine managers to continually improve the skill levels of people, to apply and develop rapidly changing technologies and to consider far broader business issues that need to be managed in a truly globally connected world. This paper will attempt to outline some of the issues, the complexity surrounding them and some of the approaches that have been made to manage them. There is not a single correct answer or approach, but there are many key success factors that have led to some amazing levels of performance being achieved as we go deeper, broader and literally move mountains to meet the customerÆs needs for today and tomorrow. This contrasts with many mining operations in developing countries that still have a traditional approach to how they mine. Society is the river of life that continually flows and changes the environment that surrounds it. The pressures from the customers and world growth, shape and force alterations to be made in an industry that has to live with the far greater primal and uncompromising forces of the earth we mine. This has led to some paradigm shifts in how we accept what we manage. TodayÆs mine manager must manage a far broader range of issues, than just how do we get tonnage out of the mine and product out of the ore. These include but are not limited to technical, commercial, product quality and end use understanding, employee and community issues, environmental and the ever increasing complexities of sustainable development. Organisations will have to look at how they structure their management of the business to manage functions to meet the complexity of different stakeholders needs û the business, the employees, the customer and the broader community within an environment that is becoming more attuned to the harm impacts to the world in which we operate. The attraction and retention of skilled people that contribute to the value and worth of the corporation, will become critical to sustain a companyÆs growth. One of the fundamental elements of successfully doing this will always be the skills of the mine manager and his/her extended team with the continued development and support that they will need to meet these demands.

Jan 1, 2006