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In order to realise seafloor massive sulfide (SMS) mining, the environmental baseline survey around targeted SMS mining areas and the creation of an environmental assessment technique suitable for quantifying the impacts of ocean floor mining are necessary. The targeted areas generally host large chemosynthetic communities in association with active hydrothermal venting. The ecosystem structure around the chemosynthetic communities has not been clarified yet in macro-scale or quantitatively. The systematic approach and plan for the baseline survey and the environmental assessmentÆs basic studies are introduced. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By Andrews JRG

Chrysotile asbestos is a valuable resource. Used as a reinforcement in asbestos cement, products are obtained which are cheap, are not attacked by vermin, do not rot or support growth of fungi and are unaffected by water or humid conditions. Such products are of great value in the developing countries where inexpensive and durable building materials and pressure pipe are very important to development, housing and water supplies. Concern over the adverse effects of inhaling asbestos has led to the introduction of increasingly stringent controls world wide on the quantities of airborne asbestos per- missible in the occupational situation. Wet processing has the potential for virtually eliminating the environmental concerns with asbestos dust both in fibre production and in the materials handling section of the manufac- ture of asbestos cement products. In addition, high efficiencies associated with wet process- ing mean that better yields are obtained and that the tailings which are dumped have a lower residual asbestos content. Since early 1977, ICI Australia and Woodsreef Mines have been engaged in a programme of research to develop and evaluate a wet mill- ingprocess to produce, from ore and existing tailings, high grade fibre suitable for use in asbestos cement products. The process has been developed through microscopic studies, labora- tory bench scale experiments, work in a small scale semi-continuous plant and product evalua- tion on experimental size Hatschek asbestos cement machines. A prototype mill with a normal feed rate of 1z tonnes per hour and capable of producing pipe grade asbestos from Woodsreef ore has been constructed and was operational from January, 1982 to July, 1983. A range of asbestos cement products have been made successfully on full scale Hatschek machines using fibre from ore and tailings milled in the prototype mill. Economic evaluations indicate that a wet process mill would be cheaper to build, operate and maintain than an equivalent dry process plant. A commercial plant has been designed 1. Manager New Process Development, Woodsreef Mines Limited, Barraba, Australia. 2. Senior Lecturer, Department of Chemical Engineering, Monash University, Vic, Australia. formerly Senior Research Officer, Research Department, ICI Australia Limited

Jan 1, 1986

THE manufacture of Portland cement on a commercial basis dates back to the year 1824, when Joseph Aspidin, of Leeds, patented his process. It was, however, only within the past 25 years that the cement of to-day commenced its history, and during that period manufacturers have constantly tried to improve the grade of cement.The introduction of the rotary kiln at the opening of this century was the starting point of rapid development in the process of manufacture, and in the quality of the cement produced.Following on the rotary innovation came the wet process. This at first was used only where the raw materials were of a soft nature; but to-day nearly all classes of materials can be treated by this method. Oompared with the dry process, it allows for greater refinement of raw materials, more intimate mixing, better chemical combination, and economy in fuel. Taking advantage of this, the manufacturers in England and America are in a number of cases substituting the wet for the dry process.Subsidiary machinery throughout the factories, such as crushing and grinding mills, have also been vastly improved. The chemists, too, have done their share in the work. Long and careful research has proved the necessity for accurate proportioning of raw materials, thorough mixing, and very careful burning. All these factors combined have given us the product of to-day, which is consistent within very narrow limits, and far superior to that of the beginning of this cement era.

Jan 1, 1926

By Doyle J

The direct method of gas content determin ation developed by McCulloch and Diamond of the U.S.B.M. has been adapted to estimate the gas content of coal seams from slim exploration borecores in the Southern Coalfield. Emphasis has been placed on the measurement of this parameter without the physical destruction of the core which is required for subsequent chemical analysis. In field and laboratory equipment is simple and inexpensive. It enables the determination of lost and desorbed gas from a fresh geological core. Residual gas is not measured but is considered to be relatively low and of no consequence in ventilation considerations. Results to date show good correlation with those obtained from underground face samples. Gas contents from the mined seams varying from 2 m3/tonne to 14 m3/tonne have been measur- ed with this apparatus. Gas desorption characteristics of South Coast coals have been found to closely follow exponential mathematical Models.

Jan 1, 1983

The paper considers the factors that will control the importance and the nature of R & D required by the Australian mineral industry over the next decade. The process required to determine the appropriate priorities for research and how it must be managed is described. The work of the Australian Mineral Industries Research Association is used to illustrate this process.

Jan 1, 1986

Eleven years ago I addressed delegates to the Whyalla Meeting of this Institute on the subjects 'Oil in Australia?' -- a title which was followed by a large question mark.My purpose at that time, which was before Rough Range, was to interest members of this Institute in the possibility of oil in this country because I considered that exploration for mineralwealth was our concern.I doubt if I made much impression.but.I recall that the Chairman at that Meeting, Mr Ian McLennan, asked me pointedly to name the areas I-would select and I nominated the Northwest of Western Australia,'Gippsland and the Roma District

Jan 1, 1962

In a state-of-the-an review of predictive methods for longwall support load calculation, special respect is paid to those techniques which enable actual roof conditions and local lithology of strata to be involved. Principal systems of roof examination include the borehole perforation test and seismic velocity measurements. Roof strata stability is related to caveability classifications and roof inclination due to subsidence. The critical analysis of both load resistance prediction methods and roof stability classifications shows that each has its own value of reliability level. The present research opportunities analysed underline the significance of developing fully reliable prediction techniques as needed by the coal industry.

Jan 1, 1991

Low tonnage quartz vein-hosted stibnite lodes are widely distributed in rocks of the Tasman Fold Belt System in eastern Queensland, with particular concentrations in the Hodgkinson - Broken River Fold Belt and to a lesser extent in the Gympie Province of the New England Fold Belt: Higher grade deposits have been worked intermittently on a small scale since 1873, resulting in the production of about 5500 tonnes of antimony ore/concentrate with an estimated grade of about 55% Sb. Future production of antimony may be as a by-product from deposits, currently being explored/mined for gold in the Hodgkinson/Mitchell River area and the Amanda Bel goldfield. Establishment of an antimony processing plant in Queensland using the Quelar Process would provide a more reliable market for small producers and could stimulate future exploration and production.

Jan 1, 1990

By Shiels O. J

The major Permian coal deposits of N.S.W. are in the Sydney-Bowen Basin and associated small deposits occur in structurally isolated areas; a further deposit is present in the Oaklands Basin. - The Sydney-Bowen Basin in New South Wales comprises the sub basins, the Sydney Basin and the Gunnedah Basin. Coal measures in these basins are near the top of the Permian succession and within and below an underlying marine sequence. The coal deposits can be conveniently described in units in which the coal geology is homogeneous. The Clyde Coal Measures and Yarrunga Coal Measures contain no seams of economic significance and occur beneath the marine beds in the south of the Sydney Basin. The Greta Coal Measures are economically significant and represent a brief interlude in the marine sequence in the north of the Sydney Basin and equivalents are present in the east of the Gunnedah Basin. The Tomago Coal Measures crop out above the marine sequence east from the Lochinvar Anticline and dip southeast to uneconomic depths. The Newcastle Coal Measures are historically and economically very important and overlie the Tomago Coal Measures and these measures will continue to be important although future mining will be faced with greater depths. To the west of the Lochinvar Anticline the Singleton Coal Measures, equivalent to the Tomago and Newcastle Coal Measures, crop out. This unit represents the thickest development of coal measures in the State and has a very large potential for both open cut and underground mining. Equivalents of the Singleton Coal Measures, the Black Jack Coal Measures and the Booroomin Group crop out on the east side of the Gunnedah Basin and probably are widespread across the Basin. They have less economic potential than the Singleton Coal Measures. In the southwest of the Gunnedah Basin, Illawarra/Singleton Coal Measures crop out over extensive areas and possibly have a large potential for underground mining under low cover. The Illawarra Coal Measures are exposed along the western margin of the Sydney Basin and thicken as they dip into the Basin across a shelf. The outcrop area is currently mined and the shelf has considerable potential for future mining. The highest rank coals in the State are in the Illawarra Coal Measures in the south of the Sydney Basin. The deepest coal mining is in this area and its continuing success is of great importance to the future exploitation of the resources of the Basin. The Tomago, Newcastle, Singleton and Illawarra Coal Measures extend into and meet in the central area of the Sydney Basin but they are under thick cover and are not considered to be economic at present. Permian coal measures occur in isolated areas in the New England Fold Belt and have limited economic potential. The Oaklands Basin in the south of the State contains a large reserve of low rank coal.

Jan 1, 1975

Hatches Creek has been inactive since 1961, but with better metal prices, interest in the field is reviving.The mixed gravity concentrates which were unsalable in 1951 have been experimentally separated into salable wolfram, scheelite, and bismuth-gold concentrates, and a flow sheet incorporating magneticseparation and flotation has been developed.

Jan 1, 1965

Mining of the silver-lead-zinc orebodies at the George Fisher Mine officially started in 2000. A review of mining performance to date shows that many of the extracted primary stopes have experienced some degree of hangingwall dilution. The degree of hangingwall failure in the stopes became progressively more extensive throughout mining of the orebodies in 2001 and 2002, culminating in the unplanned catastrophic failure of the 744D stope in which the ore between 13C (2683RL) and 12L (2714RL) sublevels caved into the previously mined cavity between 13L (2654RL) and 13C sublevels. This was followed several months later by another unplanned caving event in a nearby stope, 740D. As a direct result of these unplanned failures it was decided to mine the stopes with a smaller span than had been previously planned and in a primary-secondary pyramidal stoping sequence. To limit the exposure of the stope hangingwall, a hangingwall drive is no longer developed and therefore geologists no longer have access to the detailed geological information that this provided. Geologists at George Fisher Mine have had to be adaptable and flexible in response to these proposed changes and rely more on data from drilling than mapping for their geological interpretation. The result is that the drilling cycle has become much more critical in the planning process.

Jan 1, 2003

By Nye P. B, Fisher N. H

At the second Empire Mining and Metallurgical Congress held in 1927, the Empire Council of Mining and Metallurgical Institutions was formed and it was proposed that the Council take steps to prepare a "Review of the Mineral Resources and Industries of the Empire." At the third congress in 1930, it was resolved that the proposal to institute the review should be submitted to the Imperial Conference held in 1930. This was done, and the Minerals Committee, of the Imperial Economic Committee compiled, an interimreport which was based on statistics of imports and exports, and did not consider resources and consumption.In 1942 the Institution of Mining and Metallurgy, London, wrote to the Empire Council and stated that it was desirable that the Council should be in a position to take part in decisions affecting the future of the mining and metallurgical industries. The Council communicated with the constituent Institutions regarding the nominations of two members then in England. Subsequently the Mining, Geological and Metallurgical ,Institute of India prepared a review of the mineral resources and industries of India and their post-war development, and the Empire Council forwarded a copy to the Australasian Institute of Mining and Metallurgy and asked if that Institute would submit a review on simjIar lines for Australia. The Australasian Institute arranged that the Australian review should be prepared by...

Jan 1, 1946

Gold, silver and palladium may be separated from the other base metals and sulphur contained in copper sulphide precipitates derived from the Sherritt-Gordon nickel process using a process involving an oxidation roast, a reduction roast and a Cu(II)/acetonitrile leach. Sulphur is removed as SO, in an oxidation roast and the hot calcine is reduced with carbon, or with carbon plus cuprous chloride. The resulting product contains metallic copper which is readily dissolved with cupric ions in aqueous acetonitrile solution. Copper powder is recovered by thermal disproportionation. The residue contains the bulk of the iron and precious metals and may be treated by a number of methods, including direct cyanidation or melting with suitable fluxes. Melting the residue will produce a copper alloy containing the precious metals and remove the iron as a slag. The alloy can be recycled to the copper leaching stage or sent for toll refining depending on the precious metal content. Impurities from the leaching circuit are controlled by a bleed circuit which in one approach utilizes the SO, from the calciner to produce Chevreul's salt and separates copper from the soluble cobalt and nickel. Alternatively, the bleed may be directed back to the main refinery copper boil stage or oxydrolysis stage.

Jan 1, 1982

By D R. Seaman, B Adamson, F Burns, B A. Seaman, P Manton

The Telfer concentrator, located in the Great Sandy Desert of Western Australia, consists of a dual train gold/copper operation processing ore from one underground and, currently, two open pit mines with differing mineralogy. The flotation circuit of each train was designed to operate in several modes depending on the feed mineralogy. The majority of ore mined at Telfer is processed in a sequential mode where copper minerals are first floated into a saleable copper concentrate followed by the flotation of an auriferous pyrite concentrate which is treated in an on-site hydrometallurgical plant (carbon-in-leach (CIL)). Gold is recovered as a gravity product within the primary grinding circuit, to the copper concentrate, and to a lesser extent, the CIL circuit.Since Telfer was re-opened, with a new concentrator, in 2004, the processing plant has struggled with poor copper concentrate grades, partially due to the excessive entrainment of non-sulfide gangue minerals in the copper flotation circuit and, more recently, due to composite copper particles produced when processing ore from a supplementary satellite pit that has not previously been processed through the new Telfer concentrator. Gold recoveries in the CIL circuit have also been below industry standard. This paper presents the implementation of recent changes made to the circuit to address these performance issues. The reconfiguration of the circuit has involved the installation of the following major equipment items: two ISAMillsÖ in ultra-fine grinding applications (one in the copper circuit and one in the pyrite circuit), two Jameson Cells to improve fine gangue rejection and a bank of 5 + Outotec TC30s to recovery copper and gold from the reground pyrite stream. The equipment was purchased direct from vendors and an engineering firm contracted to design and install the multi-vendor reconfiguration upgrade.CITATION:Seaman, D R, Burns, F, Adamson, B, Seaman, B A and Manton, P, 2012. Telfer processing plant upgrade - The implementation of additional cleaning capacity and the regrinding of copper and pyrite concentrates, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 373-382 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

The Charters Towers goldfield in northeastern Queensland produced over 206 tonnes of gold from gold-quartz veins hosted by Mid-Palaeozoic granodiorite, tonalite, diorite and to a lesser extent amphibolite-grade meta-sedimentary schist and meta-igneous rock. Mineralisation occurs in grouped, moderately dipping shear zones with altered wallrock rafts and a complex network of quartz veins.Over 75 per cent of the production came from three main vein systems in the central goldfield: the Brilliant, Day Dawn and Towers Hill vein systems.The Brilliant vein system is hosted by undeformed tonalite and contains north-plunging oreshoots on a north-dipping main fissure and on shorter east-dripping hangingwall fissures. The Day Dawn vein system is localised along a north-dipping dyke at the contact of two deformed granitoids in a brittly reactivated mylonite, where horizontal oreshoot plunges may be related to the original megascopic undulations in that structure. The Towers Hill vein system is hosted in two granodiorite types and has multiple ore controls.Structural analysis indicates that the distribution of the oreshoots within the vein systems is variously controlled by the primary fabric and igneous contacts of the granitoid host rocks. Splaying, changes in dip, and fissure intersections are the main controls. The largest vein systems are both in reactivated shallow-dipping mylonite, or in fissures in younger undeformed granitoids. Each vein system lies in a separate structural domain, usually where older east-striking structures are preserved.

Jan 1, 1990

By H Ishikawa, R Halomoan, S Palaniandy

The Karara iron ore project is a magnetite operation consist of open pit mining and concentrator to produce high-grade magnetite concentrate. The concentrator has adopted three stages of comminution, ie fine crushing in the high pressure grinding rolls (HPGR), primary ball milling and fine grinding in the TowerMill plus magnetic separation in between these comminution devices. Since 2014, the concentrator has increased the plant feed rate by 18 per cent. Meanwhile, the ore hardness has increased by 13 per cent to a Bond work index value of 15 kWh/t that led to a coarser flotation feed. Karara Mine has decided to shift the comminution workload from the primary ball mill to the TowerMill circuit by bypassing the 100 µm fine screen in between the ball mill and TowerMill circuits. This action has increased the circuit feed particle size distribution with a top size close to 1 mm. The specific energy consumption of the TowerMill circuit was approximately 3.4 kWh/t, and the circuit product sizes (P80) were ranged between 38 and 45 µm. A joint process improvement exercise was carried out to reduce the circuit product size closer to the magnetite liberation size, ie 35 µm. Among the activities were circuit audit, recommendation for improvement, modelling and simulation, multicomponent analysis, implementation of recommendations and quantification of the improvement. One of the key findings was the density effect of multicomponent minerals in the hydrocyclone. The analysis revealed that the low density coarser gangue minerals were bypassed to the hydrocyclone overflow stream that has resulted in a coarser particle size distribution. Meanwhile, more than 20 per cent of fine (-35 µm) high-density magnetite particles were recycled back to the mill through the hydrocyclone underflow stream and increased the circulating load. Based on these outcomes, several recommendations such as conversion to bottom feed configuration, use of smaller grinding media, high operating hydrocyclone pressure and additional grinding power to the TowerMill circuit were made to improve the overall circuit performances. Karara Mine has prioritised to implement those recommendations that have a minimal financial implication. Full-scale plant trials with bottom feed configuration and 17 mm grinding media were conducted to evaluate its performances. These trials have indicated that the grinding efficiency in the TowerMill was enhanced by 10 – 30 per cent. In May 2017, all the five TowerMills were converted to the bottom feed configuration. This paper discusses the impact of shifting the comminution workload load from the primary ball mills to TowerMill circuit and the performances enhancement of the TowerMill circuit. CITATION:Palaniandy, S, Halomoan, R and Ishikawa, H, 2018. Shifting the comminution workload from the primary ball mill to TowerMill circuit, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 163–176 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Sheng-Hui X

This paper introduces a new coal-based rotary kiln process of DRI production - the CRIMM process, which is developed by Changsha Research Institute of Mining and Metallurgy in the past years. Its main features are the use of composite pellets (in rotary kiln). The process consists of preparation of pellets from iron concentrate and coating of coal on their surfaces. The new process is able to overcome a series of defects of the conventional coal-based rotary kiln processes. A continuous test was conducted using an experiment rotary kiln (-0.6;, x 3 m). TFe of the magnetic iron concentrate used in the test is 67.25 per cent. TFe of the product DRI is 88.54 per cent, MFe is 84.11 per cent, S and P are less than 0.02 per cent. The metallisation ratio of pellet is 95 per cent. The pellet power ratio is less than 0.3 per cent. The utilisation coefficient of rotary kiln is 1.3 t/m'-d. The overall recovery of iron concentrates is 99.7 per cent. Two small industrial plants using the CRIMM process are being set up in China. Their coal consumption can be decreased to 520 kg standard coal per ton DRI respectively.

Jan 1, 1999

By K Faure

At Sams Creek a gold-bearing, peralkaline granite pophyry dyke intrudes Ordovician-Silurian metapelite and quartzite. The granite porphyry dyke has a thickness of up to 40 m, extends discontinuously for about 8 km, and intrudes thin lamprophyre dykes along its contacts. The granite dyke and gold-bearing sulphide and quartz-siderite veins within it have been deformed and recrystallised during several phases of folding, the youngest of which is Early Cretaceous.   The unaltered granite porphyry is composed of phenocrysts of perthite, arfvedsonite, aegerine and quartz in a groundmass of the same minerals, with accessory ilmenite, rutile and fluorite. K-Ar dates of amphibole from the granite gave ages of 226 and 246 Ma, but these ages may be a minimum due to resetting during the thermal and deformation events that have affected the area. Unpublished Ar-Ar data on amphibole from the granite show disturbed spectra with high temperature steps around 300-315 Ma, which is consistent with the age of A-type granites in the Buller region. Further age dating of primary and hydrothermal minerals in the granite is continuing. At least three stages of hydrothermal alteration have been identified in the granite. Stage I alteration is characterised by high fO2 magnetite-siderite ¦ biotite, which is cut by thin quartz-pyrite veinlets (Stage II). These are cut by Stage III sulphide, quartz and siderite veins, and pervasive silicification represented by quartz-perthite-albite-rutile ¦ pyrite-siderite-sericite assemblages overprints the earlier alteration stages. Lamprophyre is altered to a siderite-chlorite-sericite assemblage. Stage III sulphide veins are composed of arsenopyrite + pyrite ¦ gold ¦ galena ¦ sphalerite ¦ chalcopyrite ¦ pyrrhotite ¦ graphite, deposited by low fO2 H2S fluids. The gold contains 18-30 wt% Ag and up to 1 wt% Bi. Temperature of vein formation was estimated from vein quartz fluid inclusion homogenisation temperatures (Th 260-355oC, average 330oC), arsenopyrite-sphalerite thermometry (310-365oC) and quartz-albite stable isotope thermometry (340oC). The altered granite and the veins have been deformed, and recrystallised and competent sulphide minerals are fractured and brecciated. Alteration and mineralisation are confined to the granite porphyry and adjacent lamprophyre.

Jan 1, 2004

By C DahnTr-Lindqvist

The Kiruna mine produced about 19 Mt processed iron ore in 1999 using sublevel caving. General failure in the hangingwall has been widely studied and its mechanism is rather well understood. Failure in the footwall is more recent and not perfectly explained. Plane shear failure and Hoek and BrayÆs circular failure charts were successfully used to match the first surveyed failure surfaces. The footwall is not free yet but covered by a caved waste rock abutment whose exact behaviour is poorly known. Based on new field data and numerical models (FLAC), the following paper presents recent improvements in understanding the Kiruna mineÆs footwall failure process.

Jan 1, 2000

By R Engle, R P. McMahan, D A. Bowman, S Schafrik, W Thabet

Preventing injuries and fatalities related to conveyor system use in the mining industry is important and increases uptime while decreasing lost time. The research presented here is funded by the National Institute for Occupational Safety and Health (NIOSH), and intended to accomplish this prevention by the use virtual environments (VEs) to improve training and help miners better understand the hazards of working around conveyor systems. Two conveyor system VEs designed to teach miners about hazards and to safely complete tasks around conveyor systems were developed for this project. The first conveyor system VE, called the instructional tour, gives the miner a semi-automated tour of a conveyor system and teaches the miner about possible hazards (eg, missing guarding) and how to safely fix conveyor problems (eg, a stuck idler) using lock-out, tag-out procedures. The second, called the virtual shift, allows the miner to freely navigate around a conveyor system to detect and avoid hazards. The miner is presented with equipment failures that need to be safely repaired during the virtual shift. If the miner fails to identify and avoid a hazard or fix a failure in a safe manner, an animation of the consequences is shown to the miner, who must start the virtual shift over. The models for the conveyor system VEs were created using 3DS Max. Desktop versions of the VEs were then created using Deep CreatorÖ, an authoring application for creating interactive 3D environments. Later, more realistic versions of the VEs were created for CAVEÖ, a room-sized visualisation system, using DIVERSE, an application programming interface. In initial evaluations of the conveyor system VEs, mining colleagues have indicated great interest in such training tools. According to their feedback, these and similar VEs would provide excellent alternatives to normal classroom training and serve as positive precursors to hands-on experience. These VEs provide new miners a chance to experience hazards associated with working around conveyor systems without being in possible danger.

Jan 1, 2008