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By Zamel G. I, Zenari L. P

Technological developments in modem Tunnel Boring Machines (TBMs) and associated back-up equipment are offering significant alternatives for mining operators to consider, in the selection of equipment for coal mine development drifts, roadways, longwall gate roads as well as metalliferous mining declines and development drives.Greater flexibility in handling variable ground conditions, muck disposal and radius of turn as well as advance rates, are just some of the areas where modem TBMs can accomplish the flexibility that mine operators require to achieve cost-effective developments.Compact TBMs are achieving this acceptance because of the fundamental design of a shielded machine containing electrics and hydraulics within the forward shell, ability to achieve tight radius of curvature and grades, and ability to provide highly flexible support systems to meet all possible ground conditions.However, a single TBM design will not suit all mine developments, as each development method - while having common goals with all mine developments - will also require certain unique criteria to be fulfilled.

Jan 1, 1993

By Kadoya H, Kondo Y

The Harima works were established in 1964 and started operation in 1966. The initial capacity was 3500 t/month of zinc and 1500 t/month of lead. Until 1990 a lot of improvements had been made and the capacity had increased 6600 t/month of zinc and 2200 t/month of lead without enlarging the furnace size. During the ten weeks campaign shut-down at the end of 1990, many modifications were carried out including the enlargement of the furnace shaft area. By these changes, the capacity has gone up to 7500 t/month of zinc and 2500 t/month of lead. In the sinter plant, the amount of SO2 rich gas supplied to the acid plant was raised to 50 000 Nm3/h from 43 500 Nm3/h. An electrostatic precipitator was adopted instead of a venturi scrubber to clean the rich gas. Oxygen enrichment has been continuously operated since August 1991, because the furnace capacity is more than the rate of sinter production. Utilisation of the sinter plant is high being as much as 97 per cent and the sulphur burning rate has been increased. In 1990 the furnace was replaced except the hearth. The shaft area was enlarged to 19.4 m2 from 15.3 m2. The target blast was designed to be more than 36 000 Nm3/h. Tuyere layout was changed to prevent slag breakouts. Due to these modifications shaft condition has been very good. Automatic launder jacket cleaners were installed to increase the lead cooling efficiency. Many other improvements and developments were also made. Coke powder injection from the tuyeres has been successfully operated since April 1987.

Jan 1, 1993

The Peko copper orebody is associated with a body of magnetite rock which it has partly replaced. The primary ore averages about 9 per cent. copper and 4 dwt. gold per ton and locally IS much richer. It consists essentially of chalcopyrite and unreplaced magnetite, with lesser amounts of pyrite, marcasite, pyrrhotite, cobaltite, bismuthinite, native bismuth and native gold. The earliest formed mineral is wolfram, and the latest formed is goethite, so that the temperature of deposition ranged from about 5000 C. to 1650 C. or lower.Oxidation extends to 270 ft., which is 100 ft. below the present water level. The oxidized ore consists of cuprite and native copper, and has replaced more or less massive chalcocite of a former zone of secondary sulphide enrichment. The present zone of secondary sulphide enrichment extends from about 270 ft. to 310 ft. depth.INTRODUCTIONThe Peko mine is about 6 miles south-west of Tennant Creek township in the Northern Territory, adjacent to a small outcrop of hematite rock that projects above an otherwise featureless "bull-dust" fiat.The copper-gold orebody being developed in this mine did not outcrop. It was first detected in 1950 by a surface diamond-drill hole (DDH.1), which intersected primary copper ore at a depth of 400 to 425 ft. This ore contained from 4 to 11 per cent. copper and 1 to 25 dwt. gold per ton. Since then a shaft has been sunk, and crosscuts and development drives have been opened on the 210..ft., 300-ft. and 400-ft. levels, which are also connected by winzes. Two diamond drill holes sunk from the 400-ft. level have intersected theorebody at about 450 to 460 ft., and a winze from the 400-ft. level intersected the lode from 445 to 500 ft. At this point it is 54 ft. wide, and averages 9 per cent. copper. More recently an inclined surface drill hole (Peko No. 1) has cut the lode at 856 ft. to 921 ft., equivalent to a vertical depth...

Jan 1, 1955

By K Watters

API Management Pty Ltd (API) is currently developing the West Pilbara Iron Project (the ‘Project’). The Project is a substantial greenfi elds mining and infrastructure development proposed for the west Pilbara region of Western Australia. The Project will establish API as a new and independent supplier of direct shipped iron ore. API manages the Australian Premium Iron Joint Venture (APIJV) on behalf of joint venture participants Aquila Resources Ltd and American Metals and Coal International Inc. The APIJV was formed in February 2005 with the objective of developing a long-term iron ore export operation in the west Pilbara region.Development of Stage 1 comprises a 30 million tonne per annum (Mt/a) channel iron deposit (CID) operation scheduled to commence in the second half of 2014 subject to approvals. JORC compliant CID resources total nearly 700 million tonnes and the Stage 1 mining area comprises eight iron ore deposits located between 30 km and 85 km south of Pannawonica. Run-of-mine ore from the eight deposits is transported to a central processing facility for crushing, screening and blending into a sinter fines product, which API has named West Pilbara Fines or WPF. Construction of a 282 km main line heavy haulage railway from the Stage 1 mining area to the proposed greenfields multi-user port at Anketell Point near Wickham, is capable of accommodating large Capesize bulk carriers and providing export facilities for other third parties. Capital investment in the order of $A6 billion includes essential support infrastructure including power, water, accommodation, roads and an airport at the mine.A feasibility study for the development of the Stage 1 mine, rail and port infrastructure has been completed along with environmental surveys of the mine, rail and port areas with Public Environmental Reviews (PERs) for each submitted for public review by end 2010. Consultation and cooperation with various stakeholders of the Project areas, and early engagement with traditional owners of the respective areas has commenced. Various sampling and metallurgical characterisation programs combined with independent institute and steel mill based testing have confirmed the positive sintering characteristics of WPF ore, which is higher in alumina (3.37 per cent) than typical Pilbara ores. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

Open pit mines in the Yilgam Craton have unique hydrogeological characteristics resulting from a combination of geology, mineralisation and the complex and extended development of the regolith. The principal features of this geological relationship are:ò deep and complex multi-stage development of the weathering profile; ò steeply dipping rock layering;ò supergene enrichment; andò mining across the regolith/rock interface.These features result in large changes in permeability horizontally across rock layers; vertically through the weathering profile and along-strike in association with mineralisation and the mineralised Structure.

Jan 1, 1993

By Sutherland R. A, Rawling K. R

The Nanisivik Mine is located 750 km north of the Arctic Circle at the north end of Baffin Island in the Canadian High Arctic, and has been in production since 1976. The paper describes the regional and local geology and the current mining and mineral processing operations, including recent innovations in each area. The Nanisivik zinc-lead deposits comprise Mississippi Valley type sulphides in a block-faulted sediment sequence of Proterozoic age. The deposits formed in two mineralizing stages by replacement of the carbonate host rock. Exploration techniques adapted to the permafrost environment include high frequency EM and ground probing radar. Core drilling is done with calcium chloride brine but trials with heated flushing water indicate potential for cost reduction. The predominant mining method at Nanisivik is room and pillar. Cut and fill is used in some satellites to the main zone. Due to the permafrost, dry drilling is employed in the underground mining. The permafrost enhances ground stability, permitting large underground openings and, as a result, the use of relatively large scale mining equipment. For power conservation, a remote control system for the ventilation fans has reduced mine power costs. The milling of the simple coarse-grained ore in an arctic environment requires special techniques in the design and operation of the plant for materials handling, utilisation of waste heat, reagent selection and tailings disposal. Regulated heavy metal contents in effluents discharged to the sensitive environment are achieved by natural processes. A recent change from sub-aqueous disposal of tailings to beach type deposition within a cell in the tailings area is reviewed. Planning closure of the property presents special problems and an opportunity for innovative techniques. Approximately 25 per cent of the employees at Nanisivik are drawn from the Inuit population of the Canadian Arctic. As the first permanent industrial activity in the High Arctic some innovative approaches to employee relations were required which have resulted in a very stable, culturally mixed community in a remote location.

Jan 1, 1993

The Mt Todd Project is located 42 km northwest of Katherine in the Northern Territory. The identified mineral resource estimate for the Batman gold deposit is 66.7 million tonnes (Mt) grading 1.4 grams/tonne (g/t). Proved and Probable Ore Reserves total 42.3 Mt grading 1.5 g/t. Orebody definition and reserve estimation is based on extensive percussion and diamond drilling. Exhaustive bias analysis comparing grades produced from different drilling techniques has been undertaken. Similarly, detailed check assaying programs have been run to validate grade data produced by commercial laboratories used during the exploratory drilling phase. Significant biases were established from both studies and appropriate 'corrections' were made to drillhole databases prior to final resource and reserve estimation. 3D geostatistical modelling has been utilised for resource and reserve estimation, with specialist consultants contracted for this work. At all times, interpreted geological controls on mineralisation, provided by

Jan 1, 1994

By Montini A

The dynamic behaviour of the load in a pilot-scale ball mill has been measured as a function of axial position within the mill, end plate lifter design, load volume J (percent of mill volume), percent solids in the slurry S and mill speed N (percent of critical speed). Conductivity probes were inserted through the shell of the mill to provide online measurements of the dynamic orientation of the load in the mill. It was found that 1. the height of the shoulder of the load is increased by increasing J, S or N. 2. Measurements of the effect of S on the location of the shoulder of the load should be very useful in mill control strategies. 3. The axial centre of gravity of the load in the mill is not affected by operating conditions. 4. The presence of lifters on the feed end plate does not affect the torque drawn by the mill. 5. Holdup of slurry in the mill is a strong function of slurry viscosity and a weak function of mill speed.

Jan 1, 1986

By Richmond A

Like many industries the coal mining industry has, since the beginning of this century, undergone many changes. Technological advances and the increasing demand for fossil fuels have introduced new mining methods and techniques which allow the extraction of thicker and deeper coal seams at higher rates of production. Most new methods of mining (or for that matter any other processes) introduce problems which the engineers of the industry are expected to face and resolve. Unfortunately, spontaneous combustion has plagued the coal mining industry since the first attempts to mine coal, and is no doubt partly responsible for the reputation that coal mining is a hazardous industry. The financial loss and toll of human lives due to the occurrence of spontaneous combustion of coal in coal mines is enormous, if not incalculable. Its occurrence today is less likely to claim lives, due to both improved methods of working and in the detection of spontaneous combustion sites.

Jan 1, 1983

We outline a first version of an ambitious goal: The world's first horizontal (matrix-independent) generic sampling standard. The specific needs and requirements are overwhelming, as all the world's analytical standards follow strict matrix or material type classification pigeonholes, leading to a plethora of analytical standards. One could rightly expect a similar multiplication regarding sampling standards, yet the singular HORIZONTAL is aimed at being truly generic. Also the existing style of standards writing is cumbersome and partly contradictory. The current work is presently being pursued in CEN and European Union standardisation regimens, for which reason full disclosure and publication is not allowed. Respecting this constraint, we unofficially present selected key issues involved in developing HORIZONTAL: The objective and scope of a horizontal sampling standard is to delineate the minimum set of principles and procedures needed to guarantee documented representative sampling for all types of materials. The horizontal standard is designed for two types of use: 1. auditing/assessing/ improving the reliability of an existing sampling procedure, and 2. design and implementation of a new sampling procedure (new lot type). The principles in this standard are all derived from the Theory of Sampling (TOS), but the standard is far from a mere collection of TOS principles. Representativeness is a characteristic of the sampling process, not of samples themselves. For practical purposes, the horizontal standard follows the fundamental distinction between 'stationary lots' (0-D, 2-D, 3-D lots) and 'dynamic lots' (within TOS aka process sampling - including extended, non-moving 1-D lots). TOS' principles of 'correctness' must never be broken at any stage, lest representativeness is irretrievably lost. The horizontal standard is not written in the mandatory fashion for legally binding matrix-specific standards, eg ISO - for the present overarching purpose a different style had to be developed. The standard must be immediately understandable in full, which merits special demands, eg extensive use of didactic illustrations. HORIZONTAL introduces an all-inclusive sampling variability measure, Relative Sampling Variance (RSV) which is for sampling of stationary lots as variographics is for process sampling - RSV is to be used as a quality criterion for any stationary sampling procedure as applied to a specific heterogeneity (lot/material). The target for this standard is all individuals, companies, organisations and regulatory bodies who are responsible for sampling: technicians, process engineers, laboratory personal, academic and industrial scientists as well as project leaders, technical managers/directors and top managers. Based on current R&D we illustrate the principles promulgated by HORIZONTAL with cases from exploration and mining of minerals commodities, a Finnsh 'Autosampler' at work in the mining context (RSV) as well as sampling equipment for use in the cement and mineral commodities industries. This is an ABSTRACT ONLY. No paper was prepared for this presentation.

Mar 1, 2010

By R Valenta

Most developing projects face a range of technical and non-technical challenges, and examination of development histories can potentially provide insights into improved approaches to project development. The Kestanelik project in the Canakkale region of Western Turkey was acquired by Chesser Resources Ltd in 2008. Turkey is a significant and growing source of gold production, with sector participation by both domestic and international companies. While the broad ranges of challenges faced by developing projects is well known, there are relatively few case studies in which the range of technical, environmental, social and governance challenges are presented in a single contribution. Recent studies of undeveloped complex orebodies have particularly shown the extent to which environment, social and governance (ESG) complexities contribute to project delays and failures. The Kestanelik project faced a full range of technical and ESG complexities, and provides an illustrative example of the associated challenges. CITATION: Valenta, R, 2018. A case study of technical, social and environmental challenges for a gold project development in Western Turkey, in Proceedings Complex Orebodies Conference 2018, pp 73–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Schmidt CG

Parameters affecting gold elution using the AARL process are reviewed and critically analyzed in an attempt to optimise metallurgical efficiency and minimise costs in both current and future carbon adsorption operations. Such factors as acid washing, column geometry, elution temperatures and pretreatment reagents are discussed together with eluant water quality and eluate flowrates. Hot acid washing of carbon prior to gold elution has many benefits. Besides improving elution efficiency when eluting with regional water, a hot acid treatment preheats the carbon without causing any gold leakage. Laboratory data indicated that hot acid washing reduces the mass loss of carbon during thermal regeneration. The eluate going to either zinc precipitation or electrowinning is also relatively free of troublesome impurities (organic contaminants and ferrocyanides in particular). Because of the chromatographic character of the AARL elution where an ionic strength gradient is used to inhibit the readsorption of gold, column geometry plays a significant role. While practical considerations and capital costs may restrain the length of the elution column, high length/diameter ratios are advocated in order to promote the plug flow of column eluate. From both a metallurgical and costing viewpoint, the two significant factors affect- ing the AARL gold elution are temperature and cyanide addition. High temperature and high reagent additions within prescribed limits will improve metallurgical efficiencies, but a balance between energy and reagent costs is required in order to minimise overall elution costs. As pretreatment reagents constitute a considerable portion of the total elution costs, both the addition and consumption of sodium cyanide must be carefully considered. Lower cyanide additions may be effective in certain instances, but the more practical use of 0,6 bed volume of a 2-3 per cent NaCN reagent containing 2 per cent NaOH is advocated. This is equivalent to an addition of 20-30 kg NaCN and 20 kg NaOH per ton carbon Treated.

Jan 1, 1986

All large open pits in Australia have been mined, or are planned to be mined well below the local water table. This raises several issues that impact on mine safety, mining costs and regulatory approvals. Some pits will be æwetÆ, where they are mined through permeable horizons and where there will be measurable groundwater inflows. These will require some form of dewatering. There may also be some difficulties in the disposal of excess water. Other pits, may be ædryÆ, where they are mined through impermeable material and there are no measurable groundwater inflows but where there are stability issues related to hydrostatic pressures within the pit walls. These may require some form of depressurisation. Some pits are a combination of both. Effective management of groundwater inflows and groundwater related stability issues and the development of cost effective and environmentally acceptable dewatering and depressurisation systems requires an understanding of site specific hydrogeological conditions and practical experience in what works best for different conditions. The presentation will include an outline of the key hydrogeological factors that impact on large pits, practical methodologies for achieving dewatering/ depressurisation, and some case studies from the Goldfields, Pilbara and North Queensland.

Jan 1, 2003

An empirical method of estimating dense rock (D.R.E.) equivalent volumes erupted as airfall tephra, described in a companion paper in this volume, is elaborated, and its accuracy discussed. Estimates obtained from a single eruption can be classified as to whether they show positive, negative, or constant relative dispersion. For positively dispersed tephras (estimated volumes increasing with distance), this procedure improves the accuracy of the method. The technique is applied to selected andesitic tephras erupted from Egmont Volcano, New Zealand, during the last 28 000 years, which are found to range in volume from about 1.5 x 107 m3 up to about 2.4 x 108 m3 D.R.E. With a factor of about 16 between the smallest and largest volumes, this contrasts sharply with the rhyolite volcanoes in New Zealand, where the difference factor is usually of the order of 100. The largest tephra eruptions at Egmont are small compared to the largest debris avalanches, which have exceeded 1010 m3 (10 km3) in volume.The magnitude versus frequency relationship, calculated using a maximum likelihood method, establishes the limits of eruption magnitude at Mt Egmont as 107 to 109 m3 D.R.E. For some volcanoes, the magnitude-frequency relationship changes with time, owing to clustering of eruptions, separated by long dormant intervals. Ngauruhoe Volcano, New Zealand, is an example. Within eruptive episodes, the mean interval between eruptions of >_ 105 m3 is about 0.9 ¦ 0.65 years. The mean interval between eruptive episodes in which >_ 106 m3 is erupted, including episodes in which this volume is erupted gradually, is about 25.8 ¦ 6.6 years, and the mean dormant interval between all episodes is about 5.2 ¦ 3.0 years. At present Ngauruhoe is in an unusually prolonged dormant period, 50% longer than any in the historical record, since 1839.

Jan 1, 1990

By K Zhao, H Gong, B Li

Health and safety are the first priority for Australian minerals sector. Australia has a global reputation in the mining industry. However, accidents occur every year. Legislation and regulation are important to prevent the accident from occurring, so do the new technologies. It is sad to witness the collision incident persisting and the long called collision avoidance system (CAS) is still not widely used in underground mines. The main reason is that the existing systems are still not advanced enough. The current CASs utilise GPS, infrared, ultrasonic, RFID, Radar, electromagnetic etc have their limitations and disadvantages. For instance, GPS is widely used in a surface mine, but it cannot be applied in underground mine; Infrared and electromagnetic have the false positive problem.

Sep 1, 2024

By S Withell, K Sheehan

Whitehaven Coal (WHC) is undergoing a transformative journey, deeply committed to the principles of a High Reliability Organisation (HRO) and the establishment of a mature, interdependent culture founded on psychological safety. This ongoing commitment is not merely aspirational but is supported by performance improvements backed by both quantitative performance data and qualitative evidence of cultural progression. WHC has strategically integrated leading and lagging indicators to target fatal risk. WHC focus areas include an emphasis on strategy and risk appetite, targeted data, informed learning, proactive addressing of fatal risk and the integration of data management and technology.

Apr 16, 2024

By BLAKE DAWSON WALDRON

I must acknowledge my strategic adviser, Mr Lance Grimstone, who contributed to the development of this paper, and collated the text and figures.

Jan 1, 1994

By de Vries D, Wilson EG, Henderson GAM, Carter EK

Canberra is a planned city in which the natural environment, rather than existing development and land tenure, has until recent times at least, imposed the major constraints to development. Even redevelopment poses fewer problems than for most cities. Geological conditions have, therefore, played a significant role in determining its shape and layout. The Canberra experience has relevance for major new mining and engineering projects. The role of engineering geologists and geophysicists in Canberra's development is described, and the problems arising from the geological environment are illustrated by several case histories. Four aspects are addressed: pre-development urban geology; major engineering projects; resources evaluation, including groundwater; and post-development problem-solving. The Australian Capital Territory lies within the Palaeozoic Lachlan Fold Belt. Within the ACT the belt is composed of folded and faulted metasiltstones, metasandstones and acid volcanics, intruded by a major granitic pluton. Some limestone lenses occur. The region has been part of a land mass since Late Devonian times and landscape evolution has been very complex. Geological features of special geotechnical significance include deep but variable weathering, with slight to moderate weathering along faults to at least 70 metres depth in places, and consequential foundation problems; close jointing; weathered limestone lenses with solution cavities containing clay and water; confined aquifers containing artesian water in scree deposits flanking hills; the presence of pyrite; and poor quality and low volumes of groundwater.

Jan 1, 1986

By R Valenta, A Littleboy

Geological heterogeneity is one dimension of complexity in mining. Significant effort is put into developing an understanding of this complexity so it can be used in resource estimation, mine planning and economic modelling. However, over the decadal lifespan of a mining venture, many other dimensions add to the complexity of a mining operation. These include: technological evolution, market fluctuations; investor confidence; social norms; local expectations; and ecosystem functionality. As with geology, these factors are all heterogeneous, uncertain, time varying and represented through sparse and incomplete datasets. Recent work (Valenta et al) is beginning to show us how these risks correlate in different global settings. By analysing data relating to known, but as yet undeveloped copper deposits, this work (the complex ore body database) is demonstrating that it is the combination of issues (both price sensitive and non price-sensitive) that determine the viability of a deposit for extraction in the 21st century.CITATION: Littleboy, A, Plint, N and Valenta, R, 2018. Mining as a complex system: do we need a new model?, in Proceedings Complex Orebodies Conference 2018, pp 41–43 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Kuzmitch O, Morozov A

The main direction in the mechanisation in the mines of the Donbas and the USSR is long-face technology with complexes on the base of hydraulic supports. On the base of the 30 year old experience of exploitation of the coal clearing systems the serious data about the behaviour of the contained rock, display of underground pressure 'on longwalls and preparatory workings have been accumulated. Exploitation works in mines of the USSR are carried out at different depths: from 1000m to 1200m. There are 26 mines in Donbas, which exceed the depth of 1000m. It is the mines of Donbas, where is a rich experience of the exploitation of coal seams in various conditions. Besides, there are wide variations on the factors of the extraction thickness, depth of seam, angle of dip, occurrence of gas dynamics and others. In many scientific establishments, and in Donetsk Polytechnical Institute also, there are scientific research/results, which can be of interest for the coal mining countries.The volume of coal mining from longwall system-mechanised walls in Donbas became stable at the end of the 70s at level of 70 percent. All the efforts to increase this level have not given any notable results, not saying about the technical-economical data, which gradually deteriorate. It shows that positive progress in using the technology for the long walls is over and it is necessary to find new ways of mechanisation of coal winning.

Jan 1, 1991