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This paper discusses the impacts that advances in metallurgy and process engineering have on minerals project execution. Ausenco's business is focused on integrating minerals processing technology and the delivery of cost effective processing plants that exceed client performance expectations. The metallurgical development is a small but critical part of this process. Metallurgical development and innovation outcomes need to be transformed into an engineered solution and that solution converted into an operating plant in a cost conscious and competitive environment. Including new or innovative processes in a project flow sheet increases a project's technical and commercial risk. However, it also gives the project, and/or the engineering company, a potential advantage over projects using mainline practices. Managing the balance between risk and opportunity has been a cornerstone of Ausenco's success in recent years. Some advances in "technology" that are discussed in the paper include: larger capacity equipment new flow sheet concepts simplification of process interfaces, and more effective project strategies The common theme is that having a new idea can be the easy bit, putting it into operation effectively involves numerous people, many interfaces and strong project management.

Sep 13, 2010

In common with general experience in the iron-making industry overseas, Australia has in recent years suffered a deterioration in the physical quality of her iron ores in their suitability as a direct blast furnace feed. The increasing amounts of fines and the more friable nature of lump ore, especially in the ore from the Cockatoo Island deposits in Yampi Sound, Western Australia, have focused attention on problems of ore preparation and agglomeration, particularly sintering.Although very small pilot scale Dwight-Lloyd type sinter machines were operated at the steel-making centres at Newcastle and Port Kembla during World War II, no sizeable capacity was installed, so that ore was charged to the blast furnaces almost entirely unscreened, and the resultant flue dust was stockpiled.Towards the close of the war, the pilot plant at Newcastle was replaced by a small machine, adjacent to the flue dust stockpile, with a rated capacity of some 20 tons per hour. After approximately five months of part-time operation, this plant was closed down in January, 1945. Production was not resumed until December, 1950, when, due to a temporary ore shortage, it was decided to supplement available ore with sinter produced from the large flue dust stocks of about 300,000 tons. In spite of mechanical and process difficulties, inherent to the design of the plant, operation was continued on a two-shift basis, with several shutdowns for extensive overhaul and plant alterations, until September, 1954, when production was put on a three-shift basis. Addition of Yampi ore fines to the sinter machine burden was not commenced...

Jan 1, 1957

How the Australasian and Canadian Codes (VALMIN and CIMVal) approach mineral property valuation is described. Brief comment is also made on the International Valuation Standards CommitteeÆs interest in a global valuation standard for Mineral (Extractive) Industries and the South African SAMREC initiatives to adopt a VALMIN-like Code. The conventional tripartite classification of valuation approaches into those that are Market-based, Income-based and Cost-based is outlined. It is best practice to use as many of these approaches as possible (and as many methods as reasonable in the particular circumstances), given the quantity and quality of the data available on the Mineral Asset (which depends upon the state of development of the mineral property). The use of specific methods must satisfy the basic considerations of logic and reasonableness and the purpose of the valuation. The competence, judgement and repute of the valuer are critical factors, since all valuations are time and circumstance specific. What constitutes æMarket ValueÆ in the different jurisdictions is discussed and definitions are given. Challenges facing the globalisation of a VALMIN-type Code for the international Minerals Industry are the influence of real estate valuers and the US jurisdictional idiosyncrasies. This is mainly due to a fixation on real property rights with a preference for using real estate-like comparative sales techniques (Market Approach) to the exclusion of Income-based approaches; a regulatory reluctance in the US to accept that Resources have considerable value; and the International Accounting Standards BoardÆs preference for Historical, rather than Current Value, accounting.

Jan 1, 2002

By E Ah Mu and C R Lilley, A D. Campbell

Cave propagation is a complex process due to interacting variables such as mine geometry, rock mass heterogeneity and complex structural networks and stress fields. The Ernest Henry sublevel cave (SLC) is directly below an open pit, which provided an opportunity to observe and measure rock mass failure as the cave initiated and propagated through the pit wall. This paper describes interaction between the open pit and SLC as well as rock mass failure mechanisms observed from the start of the SLC to surface breakthrough.Cave propagation and slope failure mechanisms were found to be governed by intermediate structures, while the cave shape was largely controlled by cave-scale faults. The open pit, production-level geometry and production draw strategy were also important factors for cave and subsidence growth. Cave propagation was episodic and asymmetric in shape due to the orientation and relative position of geological structures, combined with the effects of the increasing SLC geometry and drawdown from the underlying production levels. The precursors and failure mechanism of a 2.5 Mt wall collapse are also reviewed in detail.Cave growth was simulated using a 3D, non-linear, discontinuum finite element model coupled with Newtonian Cellular Automata. Model results are compared to field observations and monitoring data to determine the accuracy of forecasts and compared models versus actual rock mass response during cave propagation.CITATION:Campbell, A D, Ah Mu, E and Lilley, C R, 2016. Cave propagation and open pit interaction at the Ernest Henry Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 311–318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

This paper discusses the history and development of the system and the benefits that are being gained for Yabulu from Solar Drying. Following the end of mining of the local Greenvale and Brolga nickel deposits, QNI Yabulu Refinery is dependent upon imported ore from over 15 different mines in New Caledonia, Indonesia and the Philippines.

Jan 1, 2003

Nickel-bearing ores in North-east Dundas have been described by A. McIntosh Reid1 as occurring at the margins of narrow dykes of gabbro, norite, peridodite and pyroxenite, which are intrusive into the Dundas series of slates, quartzites and breccias. They occur chiefly in the neighbourhood of the Five Mile, near Zeehan, as small, narrow ore-bodies which are mostly less than 100 ft. in length.The ores are massive sulphides containing pyrrhotite, chalcopyrite, pyrite and the nickel sulphide, pentlabdite.A less common nickel-bearing mineral, gersdorffite, has been recently found in an adit, which is marked on Reid's geological plan of Dundas as the Hecla mine, 30 chains south of the crossing of the North-east Dundas tramway, over the Great Northern Creek, and at an, elevation of about 350 ft. above the tramway. The occurrence is in a lode traversing the Dundas slates and quartzites, and is situated, according to Reid's plan, about 20 chains beyond the northern extremity of a narrow basic dyke which is continuous for a distance of two miles in a south-westerly direction.The mine eonsists of a prospecting adit following the course of a lode for about 275 ft. in a direction a little west of south. The low values of the lode are indicated by a bulk sample from a shallow winze about 100 ft. from the entrance which is reported by Reid to contain:

Jan 1, 1935

By J Guo, K Williams, J Y. Guo, A W. Roberts, M Jones, B Chen

Numerical simulations using the discrete element method (DEM) were carried out to investigate the flow patterns and stress field redistribution at the hopper and feeder interface. The influences of different filling heights, belt speeds and clearances between the hopper bottom and feeder surface on feeder loads were studied. Meanwhile, experiments were conducted by utilising wedged plane-flow hoppers with different configurations and horizontal feeders with various clearances. The simulation results were compared with theoretical values and experimental measurements. In terms of the cases presented in this study, simulation results reveal good agreements with experimental observations regarding the flow pattern. Being similar to the theoretical values, the simulations provide close predictions on vertical feeder loads for steady flow states, but they may show significant overestimations for initial states. Additionally, suggestions are given for relevant simulation parameters based on the comparisons shown in this investigation.CITATION:Guo, J, Roberts, A W, Williams, K, Jones, M, Chen, B and Guo, Y J, 2017. Simulation investigation of flow patterns and feeder loads at hopper/feeder interface, in Proceedings Iron Ore 2017, pp 173–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Met M, Worner H. K

In pursuance of the investigation into the influence of various elements on the properties of lead during the past year, the effect of several elements on the creep rate of commercially pure lead has been investigated; a standard initial stress of 500 lb. per sq. in. having been adopted for comparison purposes. Other work which has been carried out indicates that the relative results of creep tests may be altered by varying the applied stress, but this aspect of the problem will need to await further investigations for itscomplete elucidation. The results obtained with dilute tellurium alloys are considered sufficiently interesting, and in some respects are so extraordinary, as to warrant publicatiorr at this stage.n must be realised however that, since the results obtained appear to be at variance with those said to have been obtained in practice and those previously published, the present investigation can only be considered as a contribution to our knowledge of the general problem.Consequently it is not considered advisable or necessary to offer detailed explanation of the results given. In fact, some features of the tests about to be described will need further investigation before an adequate explanation is possible.

Jan 1, 1936

Shortly after Denny, Robson, and Irwin published their first paper in 1937, on the prevention of silicosis by metallic aluminium, experiments were begun on the practical application of the discovery.It was thought at that time that aluminium powder, to be effective in aluminium therapy, would have to be intimately admixed with siliceous dust at the latter's source. There followed several years of experimental work underground, during which the application of aluminium powder was tested in:(1) Speakers on machine columns, vibrated by drills.(2) Vials placed in drill holes to be blasted.(3) Both homogeneous and heterogeneous mixture with explosives.(4) Packages with tamping.(5) Compressed-air lines.(6) Special compressed-air ejectors for use while drilling and after blasting.(7) The discharge of ventilation fans.(8) The filters of respirators.It was concluded from this research that any adequate method of introducing aluminium powder into a mine atmosphere would require too much extra gear, supervision, and aluminium p;wder, and would interfere unduly with underground routine.Later, animal experiments by Denny, Robson, and Irwin2 showed that aluminium powder provided effective therapy when inhaled independent of silica dust. Therefore, some means of surface treatment was deemed more practical.APPARATUS USED IN THE DEVELOPMENT OF ALUMINIUM PROPHYLAXIS SAMPLINGA basic requirement was a method of sampling to assess accurately the particle-size concentrations of dispersed aluminium powder. Konimetry, though regularly practised at McIrityre, was inadequate for the research in mind. On the other hand, the efficiency of the thermal precipitator was recognized as being very high. Accordingly, the latter instrument was chosen as best suited to our needs. Through the courtesy of the Ontario...

Jan 1, 1945

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

Recent work on decoppering lead is reviewed CUS is formed rapidly even from dilute solutions of copper in lead. The mechanism of decoppering is discussed and an explanation for the retention of metals such as silver in lead is advanced. As decoppering tin appears to be an analogous process, the, Cu-Sn-S system is studied at 300°C.. CuS, which is not an equilibrium product, is found m decoppermg drosses. In the removal of nickel from lead, Ni3Pb2S2 is formed; preliminary measurements show the equilibrium nickel content to be greater than that obtained by stirring in sulphur. Decoppering bIsmuth IS thermodynamically favoured, but is complicated by the occurrence of CuBiS2 The Cu-Pb-S system IS the only one of the four studied where the equilibrium can be calculated simply, as the presence of ternary sulphIde or other phases invalidates calculations based on binary data.

Jan 1, 1971

Wet mining of auriferous gravels at L & MÆs Waikaka operation in Southland creates spoil dumps derived from stripping of a clay rich overburden, tailings from past dredging and the processing of auriferous sands and gravels. Over recent times, spoil dumps have slumped on six occasions, threatening the viability of the wet mining operation. Close examination of slump morphology, coupled with the sequence of material placement and rate of dumping suggested a mechanism associated with undrained failure of a 2 m layer of silt and sand tails forming the base of dumps.Commencing with some information on the geotechnical properties of source overburden, back analysis of failure morphology and sequence and development of undrained loading conditions from first principals, the most likely failure mechanism and factors controlling failure were defined. Based on analysis results, a scheme to stabilise the lowwall dumps was developed and implemented, augmented by continuous monitoring of pore pressures in the basal wet tails, and laboratory testing for confirmation of computed material properties.Lowwall spoil stability has improved since implementation involving changes to the method of spoil loading, and modification of wet tails composition to improve permeability and drainage of the basal wet tails under load. The method and approach to prediction and verification of failure mechanism provide a sound basis for continued mining of deeper auriferous gravels.

Jan 1, 2002

A hard lump char containing only 4 to 5 per cent ash, 0·25-0·30 per cent sulphur and a trace of phosphorus has been produced from Latrobe Valley brown coal by slow drying and carbonization of ordinary industrial briquettes at temperatures between 7000 C and 14000 C. The briquette char can be made with a variety of reactivities by varying the maximum temperature of carbonization; the higher the temperature, the lower the reactivity. The strength of the fuel compares favourably with metallurgical coke made from black coal, though it may not be quite so resistant to abrasion. Experiments in a small experimental cupola indicate that it will make a satisfactory fuel for use in iron foundries. It may also find extensive application as a smokeless fuel in other branches of industry and in household heating appliances.INTRODUCTIONVictoria, like South Australia and Western Australia, is apparently without 'significant deposits of black coal of coking quality but there are huge reserves of brown coal of high moisture content (60-66 per cent) in the Latrobe Valley (well over 20,000 million tons have been proved) and there are other important deposits in the south central portion of the State (Herman, 1952).For three decades Victorian industries, including a few metallurgical firms, have been using the briquettes made at the Yallourn factory of the State Electricity Commission of Victoria (S.E.C.). These briquettes, having a moisture content of about 15 per cent and a calorific value of approximately 9,500 B.T.U. per pound, are satisfactory for certain grate-type furnaces but they are not suitable for use in cupolas of other shaft furnaces because they disintegrate badly on rapid heating.

Jan 1, 1956

The æMountain Camp reefÆ at Alford's mine, Wakamarina,Marlborough, had no recorded gold production although assays of 5 - 26 g/t were reported, but it did produce c. l000 kg of scheelite. The lode consists of a lower massive quartz layer, and upper, cm-banded, ribboned quartz layers, and has a very low sulphide content. Within the massive layer, relict early fine-grained mosaic quartz with idioblastic scheelite is surrounded by recrystallised granoblastic coarse-grained quartz with calcite and plagioclase, in which an original ribbon banding texture is mimiced by strings of tiny inclusions. In both the banded and massive layers, rounded quartz grains, created by cataclastic milling of grain margins and along syn-vein fractures, have been partially annealed within later quartz overgrowths. Late fibrous quartz and calcite fill brittle cross fractures.   Deformation events D1 and D2 are associated with mid-late Jurassic metamorphism of the Pelorus Group, D2 producing the main regional schistosity (S2, and the earliest scheelite. D3 is an extensional mylonitic shear event that formed the dominant schistosity in Alford's mine (S3). The quartz lode was emplaced within the mylonite by a series of individual dilation pulses (D4). The D5 event caused crenulation of the S3 mylonite, kink banding and chevron folding of the S2 schist and S3 mylonite, and reverse faulting, rodding and cross-fracturing with late fibrous quartz-calcite veining of the D4 quartz lode.   Fluid influxes during successive dilations of D4 fractures progressively caused recrystallisation of earlier quartz bands on the footwall, annealing and recrystallisation of quartz along milled crystal margins and fractures, and deposition of minor sulphides. There was thus a dynamic interplay between fault dilation, lode fracture, fluid influx, lode band deposition, and lode recrystallisation. Illite-Kfeldspar al ¦ 2 Ma (K/Ar), c.30 Ma after metamorphism.

Jan 1, 1996

Solvent extraction has recently been introduced into Australian hydrometallurgical practice for the production of a high grade uranium concentrate from El Sherana ore by a sulphuric acid leach and solvent extraction process. The solvent is a 5 per cent solution of tri(iso-octyl)amine in kerosene modified with 4 per cent of a long chain alcohol. The stripping reagent is a molar solution of sodium chloride.Preliminary testing for the development of the process showed that the leach liquor was quite amenable to the solvent extraction process and that the equilibrium and rate considerations of both the extraction and stripping steps were very favourable.The industrial plant contains four stages of extraction, three stages of chloride stripping and one stage of secondary carbonate stripping. An internal type of mixer-settler is used for the stagewise contact, the design being based on tests with model equipment.The performance and control of the industrial plant is satisfactory; 99·7 per cent of the uranium is recovered for a loss of 0·3 gallons of kerosene and 0· 4 pounds of amine per 1,000 gallons of liquor treated.INTRODUCTIONThe processing of El Sherana uranium ore from the South Alligator River valley commenced in April, 1959, and thereby introduced into Australian hydrometallurgical practice the unit operation of solvent extraction on an industrial scale. Although there are now some twelve mineral processing plants in the United States and Canada using solvent extraction, its application to the field of primary hydrometallurgy is quite new. Prior to 1956 none of these twelve plants was operating and hydrometallurgical application waslimited to the refining of comparatively high grade uranium compounds and fission products from nitrate and nitric acid solutions.

Jan 1, 1961

GENERALTHE coal deposit, where it is being worked, consists of a bed of brown coal varying in thickness from 120 ft. to 200 ft., covered by an overburden of clay, drift, loam, etc., of a thickness of 22 ft. to 40 ft., and averaging 28 ft.The overburden is first entirely removed from the coal, and then the coal is excavated by. large revolving shovels which work at the bottom of the hole or open cut in the coal and deliver it in shovel bucketfuls to the transport system. The shovels owned by the Commission and available for this coal excavation are two Bucyrus steam revolving shovels, one being type 150B, weighing 150 tons, having a 21-cub. yd. bucket, and capable of digging a 47-ft. face; and the other being type 175B, weighing200 tons, having a 31-cub. yd. bucket, and capable of digging a 61-ft. face.In addition to these two steam shovels, the Commission has recently obtained a No. 250 Ruston electric revolving shovel weighing 340 tons, and having a bucket of 10 cub. yd. capacity, and capable of digging a 75-ft. face. When this electric shovel has been erected it will replace the steam shovels on the coal excavation, and the permanent transport system has been designed to take delivery of the coal from its bucket.The duty to be performed by the transport system is to take the coal from the shovels, elevate it out of the open cut, transport it to the screening house, deliver it iuto the hoppers at the top of this building, then to take the coal after it has passed over the screens and distribute the required grades to the power house and to the briquetting plant.

Jan 1, 1924

By P K. Smith, R J. Ryan, W R. H Ramsay, D C. Arne, F P. Bierlein

Turbidite-hosted, mesothermal lode gold deposits in Paleozoic metasedimentary rocks of the Buller Terrane, western South Island have a similar geological history and genesis to the Paleozoic lode gold deposits ofVictoria, Australia and Nova Scotia, Canada. In all three regions the gold deposits are hosted by interbedded meta-sandstone and meta-argillite that have been folded and regionally metamorphosed to greenschist facies, and locally in Nova Scotia to amphibolite facies. The gold deposits are typically narrow, structurally controlled quartz veins associated with dilatant zones in reverse faults or fold-related fractures. The principal vein types include: bedding parallel or concordant veins, discordant veins, saddle reefs, and stockwork veins. En-echelon and "ac" type veins are sometimes also gold-bearing in Nova Scotia. The contrasting competency of the host meta-argillite and meta-sandstone beds is an important factor in vein formation, particularly for the bedding parallel veins, which are typically developed within meta-argillite beds or along the contacts between meta-argillite and meta-sandstone. Veins found within meta-sandstone units are generally discordant. The deposits in Victoria are well known for their bedding-parallel veins, saddle reefs ( Bendigo ) and leather jacket reefs (Ballarat). Bedding-parallel veins are also common in Nova Scotia , along with a few examples of saddle reefs. In contrast, vein formation probably occurred later in the deformation history of the Reefton and Lyell goldfields, with most veins being bedding discordant and more typically aligned with the axial plane cleavage of the folds rather than bedding planes. The quartz lodes in one deposit, Globe-Progress, strike approximately perpendicular to the bedding and fold axes. No saddle reefs have been recorded from the Buller Terrane. Mesothermal vein morphology reflects the amount of fmite strain, the strain rate, competency contrasts, lithotypes, and the confirming pressures to which the system was exposed. On the basis of comparable depositional depths and rheologies of the host rocks, a controlling factor influencing the development of different vein styles (and timing) might be finite strain, as exemplified by the tightness of folding in the host rocks. Folding appears to be tighter in the Victorian rocks than in either the Buller Terrane or Nova Scotian rocks.

Jan 1, 1999

Some major mineral deposits in northern Australia are found in preconsolidation slump disturbances in the sediments.In the retransported marine sediments at Tennant Creek, breccia beds and disturbances are found which have localized later mineral deposits such as the Peko copper orebody. These disturbances are thought to result from slumping, turbidity flow and various types of "semi-fluidized" subaqueous slides intermediate between slumps and turbidity currents.Movements are found to ~ause widespread disturbances in the sediments such that subsequent mineralization can spread through a large volume of rock giving rise to orebodies greater than those localized by tectonic structures.A similarity is noted between the sedimentary disturbances at Tennant. Creek and those at Mount Isa and Mary Kathleerr. It is suggested that disturbed beds which are host rocks to ore minerals in these mines may also be due to movements of the sediments before compaction.Certain characteristics of the slumped rocks can be recognized and limited generalizations can be made about the shape, extent and habit of these host rocks and the orebodies they contain.INTRODUCTIONSubmarine slumping and· turbidity current retransport are almost entirely responsible for some types of deep marine sediments.However, little attention has yet been drawn to slump deposits and associated disturbances bedded in the sediments as features localizing later mineralization.A study. has been made by the writer of the slump and associated phenomena of the ,Tennant Creek field where many mineralized bodies, including some gold and copper orebodies, occur as replacements of coarse fragmental slump...

Jan 1, 1960

The theme of this conference is æRediscover OtagoÆ. In order to ensure the development and exploitation of mineral discoveries in New Zealand, considerable capital will be required, particularly from overseas. This paper briefly reviews the Government's foreign investment policies and procedures and highlights some trends.

Jan 1, 1992

In spite of the many contributions that have been made to our knowledge of the creep properties of polycrystalline lead, the precise influence of various factors on these properties is not yet fully understood. Indeed, the position is such that several important points in connection with the creep of lead are a matter of controversy. This has been brought about largely by the fact that, in the case of lead, the changes that are produced in the creep behaviour by slight variations of such factors as the purity, grain sizeand previous treatment are out of all proportion to the magnitude of these variations.In order to study the fundamental properties of lead as related to creep, and so gain a more enlightened perspective with which to consider the creep of lead in general, the work that is described in a series of papers, of which the present paper is the third part, has been carried out. It deals with lead in the form of single crystals.It has been shown (1) - (3) that the grain boundaries as well as the actual grains play a part in the creep of polycrystalline lead. The present work, by eliminating grain boundaries, enables the. contribution of the grains themselves to the process of creep, in other words, crystalline creep, to be studied effectively.This object was, possibly, the major one in this work.

Jan 1, 1940