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By Ricketts N. J, Smith G. D J

A hydrometallurgical process was developed for recovery of copper from copper-lead matte formed as an intermediate product at the BHAS lead smelter at Port Pirie. A plant utilizing this process was commissioned in 1984. The leach step involves oxidation of the copper-lead matte in an oxygenated acidic chloride-sulphate leachant. The results of laboratory scale testwork from which the chemistry of leaching was deduced, are presented in this paper. The rate of recovery of copper to solution from copper-lead matte depends largely_on the availability of oxygen to the sulphide surface. The optimum leach temperature is approximately 85¦C. Free acid must be supplied according to the stoichiometry of the leach reaction: Cu1.91 S + PbS + 2.91 H2SO4 + 1.455 02 = 1.91 Cu2+ + 1.91 SOj- + PbSO4(s) + 2.91 H2O + S¦ The grind size of the matte is of minor significance. Chloride concentration in leachant should be at or above a minimum of 10.0 g/l. Chloride acts to complex cuprous ions formed during leaching.

Jan 1, 1987

By Yongjin S

Datong coal Mine suffers from delays and sudden caving of its massive competent conglomerate roof. Detailed geological studies of the nature of pebbles and matrix of the conglomerate and its sparse bedding, joint and fracture structure, gave rise to investigation of water injection to destroy its strength and to control caving. Comparative investigations, including porisity, permeability, compressive strengths and water injection of conglomerate and sandstone led to empirical expressions relating various properties and to guidance for effective injection and caving practice. This new safe roof control practice should be even more improved with further research, including Modelling.

Jan 1, 1992

By Chilman G. F, Lean P. J

The New Broken Hill Oonsolidated LImited (NBHC) concentrator was commissioned in 1952 and underwent a number of expansions over the next 25 years. In 1978, the decision was taken to expand further from 1.20 million tonne/yr to 1.43 million tonne/yr. This increase necessitated a substantial modification to an already over-taxed grinding circuit. The circuit consisted of rod mills, ball mills and rake classifiers. Plant data of grinding mill performance was obtained to develop mathematical models of individual units that could be combined to simulate total circuit performance in a number of configurations. The data provided further illustration of the validity of the perfect mixing model for relatively small increments of ball mill scale-up.

Jan 1, 1983

By Mortensen JK, Lang JR

The Canadian Cordillera contains numerous classic porphyry deposits and several unusual subtypes, including the alkaline suite of porphyry Cu-Au deposits and the Tombstone magmatic suite and associated Au¦W deposits. The alkaline suite formed in collisional settings in island arcs whereas the Tombstone suite was emplaced in an active fold and thrust belt in a continental arc. In addtion to different regional settings, these suites differ in the type of underlying basement, metallogeny, and the styles of mineralization. Both magmatic suites were emplaced over short intervals, probably in response to specific tectonic events. In the case of the alkaline suite, the tectonic event promoted magmatic processes suitable for the formation of porphyry Cu-Au deposits. The tectonic environment is less well constrained for the Tombstone suite, but the result was the formation of distinctive porphyry and intrusion-related Au¦W deposits.

Jan 1, 1995

By S Harvey

An inrush of water or mud into an underground mine, or sudden subsidence above mining voids represent low probability but high impact risks in underground mining. About two such incidents involving multiple fatalities or loss of production are reported each year worldwide. On average, Australia experiences one such incident every three to four years. This paper reports the development of a Standard that is intended to eliminate fatalities due to inrushes and subsidence.

Jan 1, 1998

By Goldstone A

The paper introduces a newly developed multi-function test rig for fracture grouting. This test rig has many functions and its performance is consistent. It can control and adjust accurately the opening degree of fissures and static pres- sure; it can measure automatically the quantity of grout injected; it can measure precisely pressure drop of grout in fissures; it can test the results of injection, including effective dispersed distance, anti-filtration capacity of consolidated body, mechanical strength, etc. It can inject a single or two grouts into one or several fissures at a pressure of 16 MPa. Therefore, it is an ideal test rig for fracture injection. The paper depicts all the components of the test rig, its performance and application of the results obtained from fracture grouting tests. Examples are briefly described.

Jan 1, 1988

Recent developments in engine, transmission and control technology, likely to give rise to improved performance and efficiency of underground mobile equipment, are reviewed. Turbocharging and the electronic control of fuel pumps and injectors can improve diesel engine performance whilst minimizing exhaust emissions. Ceramic materials promise further improvements in engine efficiency. Nevertheless, electrically powered machines, equipped with trailing cables or 'travelling plugs' are expected to find increasing application where there is less need for flexibility and where the cost of ventilation and heating or cooling makes diesel engines unattractive. Voltage to frequency converters and induction motors appear to have a future in mains powered machines. Vehicles employing energy storage in the form of batteries or flywheels will find increasing application, but it is expected that they will remain a minority until there is a significant break-through in battery technology. Hydrostatic transmissions having high power density and efficiency are likely to be used more widely. Electronic control systems are likely to be used to simplify jobs and to improve performance and productivity. Enhancement of remote control systems is to be expected for work in unsafe areas, but true robot operation is considered unlikely for the moment. Attention to ergonomic factors should produce significant productivity gains.

Jan 1, 1985

By I Doye

Acid mine drainage is a serious environmental problem caused by the oxidation of sulfide minerals responsible for highly acidic, sulfate and metals-rich drainage. Several methods of mine waste management have been developed that reduce liabilities on environment. Layered co-mingling of waste rock with compacted tailings, covers with capillary barriers effect, and co-disposal of waste rock and tailings are these new methods which are used to reduce the formation of acid mine drainage. These methods shield waste rock dumps from oxygen. These techniques could prevent oxidation reaction. In this study, alkaline industrial wastes are used with acid generating tailings to inhibit acid mine drainage. The alkaline wastes selected are cement kiln dust (CKD) and red mud bauxite (RMB). These alkaline materials are used to keep neutral conditions in the fine material layer and to inhibit the metabolic activity of Thiobacillus ferroxidans which catalyses the oxidation of sulfide minerals. A series of timed static leaching tests were performed by reacting samples of mine tailings with two, five and ten per cent alkaline material in order to characterise geochemical balance between liquid and solid phases. Column tests have been set up with oxidised tailings, waste rock, CKD, and RMB. Column tests have been carried out to simulate layered co-mingling, covers, liners, and co-disposal of waste rock and tailings. Column leach tests were conducted in order to investigate the long-term neutralisation potential of alkaline materials and the drainage water quality. Bacteria counting were performed on each sample after testing. The results obtained show that the addition of alkaline materials permit the retention of near neutral conditions in the fine material layer, thus increasing water quality and preventing bacteria development. In fact, the pH results show that the use of five per cent, ten per cent CKD or ten per cent of a mixture of CKD and RMB permit the retention of neutral pH conditions in the reactive layer. At these percent rates, the concentrations of Al, Fe, Cu, Zn, and SO4 in solution are significantly reduced compared to those obtained with the tailings only. In presence of waste rock, the relative position of the fine material layer is important. When the fine material layer overlaying reactive waste rock is composted of reactive tailings with ten per cent CKD and ten per cent (CKD:RMB), a delay was observed before achievement of near neutral pH. The neutral pH conditions remain stable over time. The mixture of CKD and RMB provides a better short-term neutralisation than the use of CKD alone. The use of alkaline materials is beneficial in order to reduce the concentrations of Fe and other metals such as Cu and Zn as well as the number of viable bacteria. The use of ten per cent RMB alone does not involve the neutralisation of reactive tailings. In the cases where the fine-grained layer are below or mixed with the waste rocks, the near neutral pH values are directly reached with ten per cent CKD. However, the pH values decrease rapidly and the number of viable bacteria increases.

Jan 1, 2003

By M Manefield, G Bournival, S Ata

Asteroids contain an abundance of valuable resources such as: nickel, cobalt, gold, platinum and rhodium. Whilst the consumption of mineral resources on Earth continues to deplete, meteoroids have the potential to become a significant source of minerals. Even though the minerals content of asteroids may be relatively high, the valuable minerals are more likely to be only a small portion of the total ore present in the main body. The ores must, therefore, be processed to extract the metals of interest from the waste. Existing terrestrial technologies rely on manipulating the physical and chemical properties of minerals. The application of these techniques to asteroids processing, however, is not straightforward due to the presence of different conditions such as zero gravity and lack of water in space. This paper discusses potential separation and extraction techniques that can be used for processing of asteroids.CITATION:Ata, S, Bournival, G and Manefield, M, 2015. Resource recovery in space, in Proceedings Third International Future Mining Conference, pp 275–280 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By M Chappell

This paper describes the design of the steel fibre reinforced precast concrete (SFRC) segmental lining for the intake and discharge tunnels for the Gold Coast desalination plant in Queensland. In addition, the key design requirements and design methods for the lining of these 2 km long, 2.8 m internal diameter tunnels, including structural, durability and maintenance requirements are discussed. Details of the segment configuration and erection process are presented along with information on the manufacture and trial testing of the concrete for the segments. The paper also gives a brief introduction to steel fibre reinforced concrete behaviour. Construction of the tunnels commenced in April 2007, and the authors believe this is the first application of this technology in Australia.

Jan 1, 2008

The use of the heavy media cyclone (HMC) Separation process for the treatment of ores in a particular size range is comparatively new to Australia. The paper describes briefly the principles of HMC operation. Reference is made to early development work, the pilot plant trials and the acceptance of the technique as a mineral dressing process. The Mitchell Cotts pilot plant at Amdel is described briefly and the results of test work on this unit for the processing of a wide variety of ores and ore types are given. Comments are made on the ob- jectives aimed at in the investigation and results are discussed with particular reference to behaviourial differences between ore types. The process is easy to operate, possesses a high capacity-to-unit-size rating and is capable of a high degree of flexibility. Further developments such as specially prepared and graded media for specific applications, automatic media density control and regulation of media consistency by the use of surface ac- tive agents and polymers have increased versa- tility and sensitivity of control to the point where products differing by as little as 0.02 of a specific gravity unit can now be separated with ease.

Jan 1, 1973

By J D. van Wees

Preliminary project evaluation is relevant to the evaluation process of the decision makers (or executives) prior to making the critical business choices. Important to the assessment is an integrated sensitivity, scenario and risk analysis at every stage of a mining project. This should include the evaluation of different options taking into account uncertainties. Construction of interactive financial computer models where each element is functionally integrated into a fully integrated life-cycle allows rapid and automatic study of the sensitivity of each element through changes in the value of an input. The scenario analysis is the effect of changing more than one input at a time, organised through scenarios in a decision tree. Risk analysis is an integrated analysis of the effect of all uncertainties of the parameters, using Monte Carlo simulation. Key to the asset decisions process is that the decision maker is provided with the essential integrated decision information. We have clustered this information into several scenario groups. Within each group, two levels of uncertain information are distinguished: discrete scenarios critical for the decisions; and remaining uncertainty within the scenario (risk analysis) which can be modelled by continuous probability density functions (pdfÆs). For an asset, the relevant scenarios in each group and the associated continuous pdfÆs need to be defined. When the scenario groups and associated pdfÆs have been defined for the asset, the decision process can be started by structuring the different scenario groups in a Scenario Tree. A Scenario Tree contains decision and end nodes. Each end node corresponds to a completely defined mine project or asset model. The calculations for each end node result in a set of stochastic realisations for the reserves, production forecast, cash flow, and profitability indicators (NPV, IRR, DPR). Thus, a deterministic and fully probabilistic multi-commodity analysis tool is provided to investigate the sensitivity and robustness of decisions.

Jan 1, 2003

By Kerkhoff G, Wood J

The maximum gas emission into underground workings can be predicted by the use of established methods which have world wide recognition. Changes in gas emission and the influence of the gas and geological environments during longwall mining at Pacific Colliery, were found.to be a typical. The relationship between longwall mining and gassy conditions is found to vary from the European experience because of the different mining and geological conditions encountered, and the higher productivity achieved, by single longwall panels in Australia.

Jan 1, 1988

By B Cope, N Hastings, D Webb

A Feasibility Study was completed in late 2002 to ascertain the risk and reward profile from the proposed deepening of operations at Perseverance Nickel Mine in Western Australia. The system and approach adopted to this brownfields extension work is outlined and the main components of the study are overviewed. In particular, emphasis is given to the integration of mine design and scheduling tools through to financial evaluation. Detailed comment is given on the ability of the system used to provide a robust project schedule complete with 3D animation. The level of importance in eliminating scheduling errors is demonstrated in relation to the reported bottom line viability of the project. It is suggested that this is an area where brownfields Feasibility Studies have lacked clarity and authenticity, leading to the creation of an unrealistic benchmark for project implementation.

Jan 1, 2003

By Mutton B. K

A systematic approach to the collection, presentation and application of structural geology data is employed in the extraction of narrow en echelon Ag-Pb-Zn orebodies by rut and fill stoping at Mount Isa. The aim is to locate, document and predict areas of adverse ground thereby enabling adequate ground support to be installed in advance of production mining. The important structural features are identified and their relevance illustrated by case histories of previous failures. The methods of collection, documentation and application of data are discussed.

Jan 1, 1977

The geology of an area in north-western New South Wales, bounded by the South Australian and Queensland borders, latitude 32° S. and longitude 14° E. is discussed.The area involved includes sixteen 1:250,000 standard military sheets and covers approximately 96,000 sq. miles.The geology of the Willyama Complex is not dealt with but a small area of metasediments previously included in this unit is separated and a possible correlation with Precambrian to the east is suggested. Torrowangee Group sediments are described and the problem of nomenclature using a glacial implication is raised.Nine areas of proven Lower Palaeozoic sediments are considered and their relationship to the boundaries of the Bancannia Trough outlined. It is possible that some exposures not yet substantiated by fossil evidence may prove to be Lower Palaeozoic rather than Precambrian in age.The sediments of the Lachlan Geosyncline in the area of the Cobar massif are described and new concepts on the age and distribution of some of the established stratigraphic units are introduced. The absence of rocks of Middle Silurian age probably indicates the time of a major orogeny in this area.Lithology, thickness, and distribution of the Upper Devonian sediments is considered and some of the more recently found fish plate localities are listed.Mesozoic sediments occur in isolated areas of Lower Jurassic age and in the Great Australian (Artesian) Basin. A four-fold subdivision of sediments of the basin has been possible in some areas but lack of sub-surface information at present, precludes the possibility of correlation with the type sections in Queensland.Units in the Cainozoic are subdivided and a five fold subdivision of the Quaternary, at present being used throughout western New South Wales, is described.

Jan 1, 1969

By W Boughton, L Gilbert

The Australian Water Balance Model (AWBM) has found widespread use in Australia in estimating the streamflow behaviour of catchments. It has been used at the Ridgeway Gold Mine, in central west New South Wales, to estimate streamflows in creeks potentially affected by loss of spring-fed baseflow due to mine dewatering. The AWBM estimates are used to assess the effect of mining on streamflows and the need to provide compensatory flow releases, which would be drawn from mine water supplies, into the creeks, in compliance with regulatory consent requirements. The monitored flows in some of the creeks exhibit non-typical behaviour, with streamflows increasing in autumn months despite a lack of significant rainfall. This behaviour is believed to be due to the combined effects of discharge from rock fractures and the effects of evapotranspiration in the riparian zone. A modified version of the AWBM has been developed which much more closely simulates the observed flow behaviour and which will be used in ongoing flow assessments for the mine. This paper outlines the difficulties involved in modelling low flows in small catchments that are subject to a number of influences (other than mining), describes the development of a refined model to improve simulation of low flows and baseflow in small headwater catchments and highlights the need for good baseline data to calibrate such models.

Jan 1, 2006

The sixth international symposium on mining with fill nearly coincides with the 25th anniversary of the Jubilee Symposium on Mine Filling. That symposium, held in August 1973 in Mount Isa, in part to commemorate the 80th anniversary of The Australasian Institute of Mining and Metallurgy, was the first in what has turned out to be a very successful series of symposia. Subsequent symposia were held in Sudbury, Canada (1978), Lulea, Sweden (1983), Montreal, Canada (1989) and Johannesburg, South Africa (1993). The series of symposia has now become an established part of the mining industry calendar, and it will be interesting to see which country is given the honour, and accepts the challenge, to organise the next symposium.One way of predicting the future, or some small part of it, is to revisit where we have already been with a view to determining the existence of any trends that may impact on the future. An historical review of filling practice and research, with special emphasis on Australian experience in particular and worldwide in general over the previous 25 years, will enable me to address the historical and predictive objectives. Controversy can always be achieved by producing a best of list; it can be guaranteed that everyone will disagree with at least one of the nominations. On this occasion, the best contributions by individuals or groups in a number of areas of mine fill technology, over the last 25 years, will be the basis for the nominal awards. The controversy can be increased by posing a number of questions that, hopefully, some of the authors will address during their presentations. I imagine the social functions will be busy enough, but the questions may just add to the cut and thrust of the debate.

Jan 1, 1998

A good blasting result is largely achieved by putting the right amount of explosive in the right place and firing it in the right sequence. The best blast design in the world will not break the rock if the planned blast layout is not achieved in the field. One of the critical inputs into a blast design is the diameter of the blasthole. An assumption that the actual blasthole diameter is equal to the nominal drill bit size is generally made. However, a small deviation in the actual hole diameter from that assumed will have a dramatic effect on the hole's volume and, consequently, where the explosive is placed in the blasthole. Any discrepancy in actual blasthole volume from that assumed will be reflected in 'overloading' or 'underloading' of the blasthole with the calculated explosive quantity and, thus, reflect in explosive distribution and stemming lengths. When loading to a 'collar' in an oversized hole extra explosive will be used, resulting in higher than planned powder factors and explosive costs. A blasthole diameter assumed from a nominal drill bit size is an incorrect assumption. This paper will present some actual blasthole diameter measurements illustrating the variation in hole diameters seen in the field and proposes a practical method for achieving a useful blasthole diameter measurement.

Jan 1, 1990

By D Whitworth

The Golden Pig mine has embarked on a diamond drill program design philosophy that increases flexibility of the program by greatly increased drill pattern densities. The use of standard broad pattern diamond drilling at the Golden Pig mine has previously lead to operational inefficiencies and impacted significantly on the costs of the mine. The diamond drill program philosophy and its interaction with mine planning is explained. The case study of the E lode mining as used to internally justify the increased drill densities is detailed.

Jan 1, 2002