Search Documents

In 1972 the Marra Mamba Iron Formation in the Lower Proterozoic Hamersley Iron Province of Western Australia was recognised as a stratigraphic horizon with significant potential for high grade iron ore reserves. Within the Newman area the Marra Mamba Iron Formation has been subdivided into four strati- graphic units: Lower BIF member, Middle BIF and shale member, Upper BIF member and Upper shale member - and a standard natural gamma log reference section compiled for the entire formation. The recognition of the Upper shale member as an additional unit contrasts to the previously proposed stratigraphy. Enrichment of the Marra Mamba Iron Formation to ore grade (0)8 percent calcined Fe) in the Newman area is restricted to the Upper BIF member and to a lesser extent to the Middle BIF and shale member. Typical ore from Orebody 29 is friable interbedded martite-ochreous goethite, signifi aptly different both physically and chemically from the Brockman Iron Formation ores of the Tom Price-Whaleback type. Large scale customer acceptance trials (in excess of 4 million tonnes) have shown that Marra Mamba ore crushed to fines and blended with Mt. Whaleback fines in a ratio of up to 15:85 forms an acceptable sinter feed.

Jan 1, 1981

By K Zic, P Pickering, P Fraser

Water is a defining feature of the Pilbara. Its management was and remains vital for the pastoral industry which European settlers established when they first came to the Pilbara, and for the mining industry which now dominates economic activity in the Pilbara. Water availability in the Pilbara is, however, problematic. Severe droughts and major floods can occur at close intervals. In response to this uncertainty, the Department of Water undertook a Prefeasibility Study to determine, at a high level, the water requirements and opportunities in the Pilbara region. This paper reports on the outcomes of this study and the water integration opportunities in the region, identifying the sources of water supply and offers possible options for managing this water sustainably for the present and future demand. A range of supply opportunities is reviewed including: dewatering from mining operations, surface water, and desalination. All opportunities were subject to order of magnitude costing, including capital, whole of life and retail unit pricing with preferred options receiving further interrogation through triple bottom line (TBL) analysis to prioritise solutions. Options were also subject to intangible quantification (IQ) including benefits from the reduction of carbon emissions to ensure that the preferred option is based on factors other than just the least cost. Demand analysis was undertaken to identify current and future requirements and were assessed through review and integration of regional and sub regional master plans and consultation with mining, agriculture, industry and the community. The paper concludes that the viability of a Pilbara integrated water supply scheme depends on the development of a financial mechanism involving both government and industry participation models. The agreed scheme formed the basis of a submission to Infrastructure Australia for funding assistance.

Jan 1, 2009

By Allnutt S. L, Radojkovic A. M

Century, a major shale hosted zinc deposit in the Riversleigh Fold Zone of northwest Queensland's Mount Isa Basin, was discovered by CRA Exploration in 1989. A total of 322 drill holes, completed by the end of 1992, define a resource of 118 Mt of mineralisation averaging 10.2 per cent zinc, 1.5 per cent lead and 36 grams per tonne silver. Mineralisation is developed in the upper portion of Lawn Hill Formation Unit 4 (Pmh4). The intersection of the Termite Range and Little Range Faults, major regional structures, may have been important in controlling mineralisation development. Three listric normal faults, and an unconformity between Proterozoic rocks hosting mineralisation and overlying Cambrian carbonates, divide the deposit into three distinct blocks. The deposit is essentially blind, outcropping in only two places. The deposit is characterised by an extremely simple sulphide mineral assemblage, sphalerite being the most common sulphide phase. Pyrite, the most common phase in many other shale-hosted zinc-lead deposits, accounts for only five per cent of all sulphides present. Siderite is the principal non-sulphide phase present. Both sphalerite and galena have near stoichiometric compositions. Sulphides are confined to carbonaceous shale horizons. Intervening siltstones are essentially barren. Shale and siltstone beds forming the mineralised sequence can be correlated across the entire deposit area. Systematic grade variation occurs within each mineralised shale bed. Although sulphide laminae parallel primary lithologic layering, the point of most intense mineralisation development transgresses stratigraphy. Bituminous material is intimately associated with sulphide mineralisation.

Jan 1, 1993

Curragh Queensland Mining Limited, a co-venture of Australian and overseas interests, operates a large multi-seam strip coal mine in Central Queensland. Coal uncovery is by four large walking draglines.Mine planning is an essential and strong component of the Curragh operations so that informed short- and long-term management and operational decisions are made.

Jan 1, 1992

The liquid products of low-temperature carbonisation of coal are of variable composition, very much influenced by the rank and type of coal, and process parameters. In general the tar contains a high proportion of phenols and a low proportion of bases. The neutral oil is more analogous to a thermally cracked petroleum oil than to a high temperature tar. Present practice and possible future trends in the production of chemicals and liquid fuels from low temperature tar are reviewed in the light of recent work on the detailed composition of the tar The phenols and aromatics will probably continue to be of most value, with the bases a useful source of spec- ialty products. However the high aliphatic content of the neutral oil (particularly 1-olefins and n-paraffins) is bound to receive more attention for chemicals as well as for liquid Fuels.

Jan 1, 1969

The article presents methods of testing and recording of water amount pumped out in surface mining. The authors describe necessary recommendations how to carry out measurements so that one can separate the surface run-off and groundwater inflow from the total inflow. They demonstrate methods of evaluation of these kinds of inflow in open pits when water amount testing is carried out every eight and 24 hours as well as simple methods when only monthly records of water are available. The authors also describe procedures for evaluating the water inflow when an open pit is dewatered gravitationally and measurements in discharge channels are irregularly carried out.

Jan 1, 2003

By H Austrheim, A K. Engvik, A Putnis

How aqueous fluids move through rocks and minerals is a question of possible pathways and mechanisms. Existing pathways such as fractures and grain or mineral boundaries provide obvious channels for fluid movement. We show how minerals reactive in the presence of an interfacial fluid can be replaced by new product phases through a process of interface-coupled dissolution-reprecipitation. A resulting porosity in the new phase provides a new pathway for fluid movement and therefore mass transport through the mineral, which progressively reacts at a moving interface. Eventually fluids of new and changing composition can pass through originally solid minerals and move on further, taking remobilised elements with them, to be reprecipitated whenever the chemical and/or physical conditions allow. One such example is albitisation of rocks associated with mineralisation.

Jan 1, 2008

The growth of the mining industry around Australia over the last ten years has seen many open cut mines developed on shallow oxide reserves. Most of these have been gold operations, although there are some copper mines in the list, too. Many of these have exhausted their oxide reserves and have made the transition to underground mining to access their deeper sulphide ores. Other operations have reached or are approaching the point where the decision has to be made to go underground or cease mining. This paper discusses the issues involved in making the transition from surface to underground mining. The aim is not to discuss each of the issues exhaustively. This would take a conference in its own right. Nor is it intended to provide a primer on underground mining. Instead the aim is, firstly, to flag the issues which must be addressed when planning to make the transition from surface to underground mining and, secondly, to identify critical aspects of mine development.

Jan 1, 1997

By Payne AR

The high cost of gateroad repairs and maintenance in U.K. longwall coalmining is a clear indication of the failure of permanent support systems to fulfill their prime function, i.e. control of strata movement. The main component of gateroad support is the pack, the design and materials of which have experienced an important development process during the last 10-15 years. More recently, research investigators have attempted to give a design basis to pack quality and dimension, and reference is made to two theoretical approaches. In the course of a current research programme based upon in situ monitoring, interim design recommendations have been proposed as a means of effecting improvement in support efficiency. Identification of characteristic deformation behaviour forms the basis of the recommendations made and the subsequent improvement in gateroad performance reported.

Jan 1, 1986

By Scott A

The object of most blasting operations is to destroy the insitu structure of the rock mass so that mechanical equipment can efficiently excavate the rock fragments. In achieving this objective the blasting engineer is also concerned with minimising damage to the adjacent rock which forms the mine structure relied upon to provide support. Damage to this "structural" rock is undesirable but usually occurs as a result of two distinct processes: ò readjustment of stresses around the excavation as a result of the mining process itself ò impact of vibration and high pressure gases from blasting operations. Gross damage to mine structures from either cause is observed as visible alteration to the appearance of the rock structure in the form of cracking, slabbing, back or over break and visible displacement. Recent work at the Julius Kruttschnitt Mineral Research Centre (JKMRC) has shown that significant reduction in the strength of a rock mass can take place well before the onset of these obvious signs of damage. It has been demonstrated that the effect of blast damage on the behaviour of the rock mass can be many times more prominent than the effect of stress redistribution. This offers the blast design engineer the opportunity to significantly reduce blast induced damage to rock structure by modifying blasting practices. This paper introduces the current JKMRC postgraduate research projects investigating the evaluation and control of blast damage.

Jan 1, 1990

By D Bradshaw

The recovery of molybdenum at Kennecott Utah Copper (KUC) has become increasingly important as its demand and price have risen dramatically in the last few years. Consequently, the flotation behaviour of the molybdenum bearing mineral, molybdenite, has received a significant amount of attention. The flotation performance of molybdenite generally lags that of the copper sulfide minerals and is much more variable. There are many factors including particle size, liberation, surface slimes and oxidation that contribute to this and also much speculation as to the relative contribution of each of these factors. This paper discusses the morphology of the molybdenite found at KUC, the mineral associations in the different lithogical ores types and the effect that each of these has on flotation performance. Quantitative mineralogical analysis and an assessment of particle shapes are used to explain that flotation behaviour does not necessarily follow expected trends and that some behaviour is counter-intuitive. This unique behaviour can be explained by the morphology and anisotropic nature of molybdenite.

Jan 1, 2008

By J P. Wyethe, D P. Padayache, B R. Green

The development of an ion exchange process for the recovery of vanadium from solutions containing low concentrations of vanadium and/or slurries is discussed. The process can be used to improve overall vanadium recovery throughout the plant, and/or to reduce the vanadium concentration of waste materials prior to their disposal. The development of the process on a laboratory and miniplant scale is discussed, and includes:selection of a suitable resin with the desired loading and elution characteristics; laboratory-scale testwork to evaluate the use of the resin in both resin-in-pulp and fixed bed configurations; recovery of a high-value vanadium product from the resin eluate; and a preliminary techno-economic assessment of the financial viability of the process.

Jan 1, 2000

By Cunningham DA

Plant based on the New Jersey refluxing process has been installed at the Cockle Creek Works of Sulphide Corporation Pty. Limited to refine portion of the zinc output from the Imperial Smelting Furnace. Refining of impure zinc is effected by distillation in two stages in vertical columns compris- ing a series of superimposed silicon carbide trays designed such that ascending zinc vapours and descending liquid metal are in intimate contact. In the first stage the volatile elements (zinc and cadmium) are distilled from impure metal, condensed, and while still molten, fed to the second column in which zinc is boiled under controlled refluxing conditions to remove the cadmium content. The resultant zinc has a purity in excess of 99,995 per cent zinc. The availability of refined zinc has made possible the production of a number of zinc alloys for marketing in addition to the basis grades of zinc.

Jan 1, 1969

By O N. Antzutkin, W Forsling, K J. Pike an

The adsorption mechanism of three different O,OÆ-di-alkyl-dithiophosphate (dtp) collectors, K[S2P(OR)2] with R = Et, i-Bu and i-Amyl, on the surface of synthetic chalcocite (Cu2S) was studied by means of solid-state 31P CP/MAS NMR spectroscopy. The morphology changes on the conditioned Cu2S surfaces, in the collector concentration range 0.1 - 10 mM, were also monitored with scanning electron microscope (SEM). In order to assign Cu(I)-dtp species on the surface of Cu2S, the corresponding bulk Cu(I)-dtp compounds, which are clusters of the monovalent copper containing either Cu6(antiprismatic) or Cu8(cubic) cores, were synthesised, and characterised by means of solid-state 31P CP/MAS and static 65Cu NMR. Further investigations on the crystal habits of the bulk systems were carried out by powder x-ray diffraction and SEM. A comparative analysis of the 31P chemical shift and chemical shift anisotropy (CSA) data estimated from the experimental NMR spectra of the polycrystalline bulk Cu(I) dialkyldithiophosphate complexes was used for assigning the 31P resonance lines in the NMR spectra of the collector treated Cu2S powder samples. The species formed on the synthetic Cu2S surfaces were assigned to polycrystalline phases of: Cu6L6 with L = Et2dtpû, Cu6L6 and Cu8L6(S) with L = i-Bu2dtpû, and Cu8L6(S) with L = i-Amyl2dtpû. A heterophase autocatalytic step process of both formation and growth of solid CuxLy (L = R2dtp, x = 6 or 8 and y = 6) complexes on the collector treated Cu2S surface is proposed. A possible role of the oxidised form of dithiophosphate collectors, bis[di-alkyl-thiophosphoryl]-disulfane (disulfide), is discussed in terms of a specific self-redox reaction. The second order quadrupolar lineshapes in 65Cu NMR spectra were simulated and the interaction parameters, CQ and hQ, for the bulk dialkyldithiophosphato-copper(I) complexes were obtained.

Jan 1, 2005

The importance of good winding rope practice is stressed. Details of the ropes used for various duties in the four shafts of The Zinc Corporation, Limited (ZC) and New Broken Hill Consolidated Limited (NBHC) are given. Inspection, testing (including non destructive methods), maintenance and rope discard criteria are discussed. There are sane catments about rope installation methods and an appendix is included which outlines the appropriate statutory requirements for winding ropes in New South Wales (NSW).

Jan 1, 1983

By Stitt P. H

This paper provides a brief historical review of the invention of the spiral separator and its adoption into Australian metallurgical practice. The purpose of the review is to demonstrate that spiral development to date appears to have been a largely empirical process, and that the cur- rent resurgence of interest in the spiral, especially in the coal industry, warrants an increased fundamental research effort. Current research work concentrating on empirical modelling is outlined, while some preliminary experimental results of a more fundamental nature are presented and some research of other disciplines interested in particle transport introduced in order to stimulate further work and discussion.

Jan 1, 1988

By Williams JK, Bolitho BC

Laverton Gold NL (Laverton) is the first junior Australian mining company to establish a viable mining operation in Indonesia. It successfully commissioned the Rawas plant in Sumatra this year with an average anticipated production of 85 000 ounces of gold equivalent (as gold and silver) per year, a feat of which Laverton is justifiably proud.Working in Indonesia and South-East Asia generally is very stressful for juniors and stretches human and financial resources to the limit - more so than in medium to large companies which can absorb the workload in-house more effectively.

Jan 1, 1997

Feasibility is a value improvement process for projects. At any stage in project development, a feasibility study can be undertaken, but although the scope generally remains unchanged the extent of detail and level of accuracy usually increases with time. The main scope elements are a business definition, project description and an execution plan. The studies are designed to assess the potential of the project and to secure funding for on-going examination. Invariably, the investigations loop back to earlier stages to establish more appropriate development criteria but a critical stage is reached when a project construction decision is requested. This feasibility study requires very detailed presentation and analysis to a higher accuracy for the owner(s) and their potential lender(s).

Jan 1, 1997

A broad zone of intra-plate volcanism occurs for some 3000 km along the E. Australian coastal regions, extending from far northern Queensland southwards to Tasmania, westwards to western Victoria, and into southeastern South Australia. The age range, taken over the whole region, extends from Eocene to Holocene. Wellman & McDougall (1974) recognised the occurrence of three distinct types of volcanic occurrences: (a) Lava field provinces, dominantly basaltic and commonly strongly undersaturated, but of variable size. Large lava fields are especially exemplified by the younger provinces in northern Queensland (e.g. Nulla, McBride), and western Victoria. (b) Central volcano provinces, in which a reasonably well defined volcanic edifice is discernable. Such provinces are built of mildly undersaturated to saturated mafic lavas, but are also characterised by felsic volcanism (and often substantial mafic and felsic intrusive phases). Examples are the Springsure-Minerva Hills province, the Tweed and Focal Peak Shields (southeastern Queensland to northeastern N.S.W.), and the Nandewars, Warrumbungles, and Canobolas volcanic centres (N.S.W.). (c) A single leucitite province in N.S.W. Wellman and McDougall (1974) were able to show that the central volcano provinces exhibit a remarkably regular southward age migration pattern, the calculated migration rate being 66 + 5 mm yr , and these authors interpreted this in terms of the northward passage of the Australian plate across a fixed 'hotspot' within the upper mantle. The leucitite province also fits this migration pattern. The lava field provinces apparently exhibit more erratic regional age distribution patterns, but Sutherland (1981) has interpreted the data in terms of a multiple 'hotspot' model. It is noted, however, that the youngest areas of volcanism (Pleistocene 1. Department of Geology and Mineralogy, University of Queensland, St. Lucia, Brisbane, Queensland

Jan 1, 1987

By Hendrix J. L, Nelson J. H

A study was conducted to examine how pretreatment of carbon-bearing gold ores with chlorine enhances gold recovery by cyanidation. It is hypothesized that metal species (including iron and copper) dissolved during chlorination adsorb on the carbon surface hindering the adsorption of dissolved gold. To test the hypothesis, samples of several sulfide minerals were subjected to reaction with sparged chlorine gas to determine which, if any, dissolve faster than gold under these conditions. Then, a synthetic carbonaceous refractory gold ore containing pyrite, chalcocite, activated carbon, and gold was subjected to gas sparging. The results of these experiments showed that chalcocite and arsenopyrite dissolve so that metal (copper and iron) is put into solution slightly faster than gold under the same chlorination conditions. Also, it was observed from the experiments that gold adsorbs on activated carbon during chlorination, but is replaced by copper and iron as the chlorination process dissolves more of the chalcocite and pyrite. The study concluded by investigating ferric chloride addition prior to chlorination to hinder gold adsorption on activated carbon.

Jan 1, 1991