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By Taylor R. N

Flow simulations have been performed on the flash-smelting burners currently used at KNS. This paper presents studies of the heat transfer between gas and particles at the burner exit. Gas and particle temperatures, velocity and concentration profiles of the two-phase flow are calculated by the mathematical model. The predicted gas temperatures have been favourably compared against values measured by thermocouples placed near the burners in the flash furnace. The predicted particle temperatures are also reasonable when compared with the measured temperatures.

Jan 1, 1992

By Gostylla W

The economic feasibility of controlled district cross-cut recirculation is examined in this paper with particular reference to the most important mine ventilation network parameters. An algorithm is developed to express the annual cost of recirculation which is then compared to the annual cost of conventional ventilation using the University of Queensland Experimental Mine as a case study. The concepts of resistance ratio and volumetric efficiency ratio are introduced and used to analyse the economic feasibility of controlled recirculation within a mine ventilation network.

Jan 1, 1988

By Fulton B, Stewart R, Leach T

Gold mineralisation at Porgera is inferred to have been derived from a deep differentiated magmatic source which is capped by a series of (now tilted) inward dipping sills and stocks, which comprise the Porgera Intrusive Complex. An arc normal transfer structure provides a conduit, at the intersection with an arc parallel structure, into which basic magma derived from the deep melting of mantle material has been emplaced. Two phases of mineralisation display an association with late stage feldspar porphyry intrusives. Stage I carbonate-base metal-style gold mineralisation occurs as early quartz-sericite, then massive sulphide and late zoned Mn-Fe-Mg-Ca carbonate vein/breccias. Magmatic fluids derived from the deep magma source, are interpreted to have migrated along the margin of a feeder stock to the sills, and south to Waruwari. Stage II epithermal Au-Ag quartz-style gold mineralisation occurs as early fluidised breccias and carbonate veining, followed by zoned quartz-roscoelite-carbonate-gold vein/breccias, and late carbonate and/or sulphate open space infill. Magmatic fluids are interpreted to have utilised the same plumbing system as the late stage feldspar porphyry intrusive, and then migrated into the Roamane Fault which was dilated by; dextral rotation on elements of the transfer structure, normal faulting, and refraction around the competent footwall hornblende diorite. Bonanza gold is localised in a jog in the Roamane Fault, hangingwall splits and at intersections with cross structures. Bulk low grade Stage I gold has been deposited by the mixing of magmatic fluids with cool gas condensate waters, whereas high grade Stage II gold mineralisation resulted from the rapid quenching of mineralised magmatic fluids by oxygenated groundwaters.

Jan 1, 1995

Structural Controls Interpretation of regional aeromagnetics, radiometrics and satellite image data has identified three structural domains (fig 2): The Fairyland Domain: a general N - S structural trend. The Cracow Domain: a general NW - SE structural trend. The Bald Mountain Domain: a general N- S structural trend. Known mineralisation is confined to the Cracow Domain in which there occurs two major NW - SE trending fault zones. The Cracow Fault Zone (CFZ) and the Immy Creek Fault Zone (ICFZ). Enhanced detail of the CFZ (fig 3) shows three main structural trends within it: NW-SE structures which include the mineralised White Hope South fault zone and the Golden Mile fault zone. NE-SW structures which have an influence on mineralisation in the Orange Creek, Fernyside and Golden Plateau areas. N-S structures comprising several major structural zones.

Jan 1, 1990

By Ormsby W. R, Nicholson P. M

Woodcutters is a polymetallic vein-style deposit hosted by sediments of the Palacoproterozoic Whites Formation which forms part of the sedimentary sequence in the central Pine Creek Geosyncline. Past production and identified resources total over eight million tonnes at 5.5 per cent lead, 12.1 per cent zinc and 110 gA silver. The local geology is influenced by Archaean basement highs; the Rum Jungle and Waterhouse Complexes. Unconformably overlying basement are interbedded clastic and crystalline carbonate units (Batchelor Group) representing cyclic changes in the depositional environment. These exhibit onlapping features with the underlying rocks. Sediments of the overlying Frances Creek Group suggest a quiet period during subsidence and subsequent increase in water depth (the carbonaceous dolomitic shales and the interbedded dololutites of the Whites Formation) followed by proximal uplift resulting in the inundation of turbiditic flows (Acacia Gap Quartzite). All of the Palaeoproterozoic rocks show evidence of being affected by penecontemporaneous, basement circling faults with steep dips. The stress regime during the deposition of the Frances Creek Group was characterised by alternating episodes of thrusting and transpression. Periods of relaxation also occurred. The compression resulted in major NS strike-slip (transpressional) faulting, en-echelon NNE trending folds and NW-SE tensional cross faults. Thrusting produced N-S striking, steep dipping reverse faults and a possible decollement immediately above the Batchelor Group. Relaxation is evidenced by the intrusion of lamprophyre dykes and dolerite sills (Zamu Dolerite). Mineralisation at Woodcutters occurred in faults within the Whites Formation, probably synchronous with deformation and the deposition of the upper parts of the Frances Creek Group. Greenschist facies metamorphism occurred as the rocks were further buried. Several massive sulphide bodies occur at Woodcutters. A number of features influence the location and shape of these bodies. They are: ò the N-S transpressional faults and in particular associated dilation zones; ò intersection of the N-S transpressional faults with the axial plane of the NNE trending Woodcutters Anticline; ò intersection of the N-S transpressional faults with the NW-SE cross-faults; ò intersection of dololutite rich units with the NS transpressional faults where local replacement takes place; ò thickening of the lithological units in the vicinity of the anticlinal axis; and ò the anticline doubly plunging to both the north and south. The mineralisation exhibits vein-like features as well as epigenetic textures. Its boundaries are sharp, its thickness varies rapidly down dip and along strike, and no alteration halo exists though stringer veins of quartz-carbonate-pyrite ¦ sphalerite/galena occur in close proximity. A number of sulphide mineral assemblages have been recognised, each separated by periods of deformation and partially replacing the earlier assemblages. Vertically continuous zonation patterns highlight the presence of rich galena-sphalerite-silver in zones of maximum dilation and pyrite-arsenopyrite-gold concentrated at the along strike peripheries. The genetic model proposed has the mineralisation occurring whilst the transpressional regime was active. It was deposited from the same fluid that elsewhere in the Geosyncline formed the stratiform deposits higher in the sedimentary pile. Hydrocarbons sourced from the organic-rich Whites

Jan 1, 1994

By Griffith L, Lama RD

West Cliff Colliery mines Bulli Seam occurring at a depth of approximately 480 m. The Seam is intersected by a number of small shear zones and faults. While the faults have caused displacement of the seam, the shear zones are strike-slip structures with small apparent displacement of seam. Outbursts at West Cliff Colliery occur while driving through these shear zones. Few outburst wave occurred where faults have been intersected. In the last 3 years, over one hundred outbursts have occurred at West Cliff Colliery. The size of outbursts varies from a small bump to exceeding 140 tonnes of coal. A number of studies have been undertaken at West Cliff Colliery to control outbursts and predict Outbursts in advance of workings. These include: geological investigations, microseismic techniques, gas adsorption studies and gas drainage. The investigations to date suggest that outbursts of gas at West Cliff Colliery are more a gas phenomenon similar to what occurs in overseas mines. The results of various investigations are reported. West Cliff Colliery is located in the mid- west of the southern coal fields of N.S.W.

Jan 1, 1980

From the viewpoint of mechanical efficiency, charges should be fully coupled and, upon detonation, should just fail to break the rock in compression. But because mining thrives on its cost-effectiveness rather than its mechan- ical efficiency, the explosive which generates maximum energy per $ should generally be used, even though the mechanical efficiency of this explosive's detonation products may be sub- optimum. Wherever possible, each charge should have a length:diameter ratio of about 20 or more and should shoot to a concavely biplanar free face that is both parallel and reasonably close to the blasthole. Success in obtaining parallel effective faces often demands the drilling of angled blastholes and, hence, will require intensified research and development efforts by drilling manufacturers, especially where hard strong rocks are encountered. Blastholes should be drilled on equilateral triangular grids and fired in a Vl or shallower V-type sequence using inter-row delays which ensure that good pro- gressive relief of burden is achieved. The conventional method of calculating Se/Be values (on the basis of planar effective faces) is often invalid.

Jan 1, 1986

By R Wynn, N Stoitis, R A. Lauten, H Liang

At the Century mine in North West Queensland, MMG produces lead and zinc concentrates. The current production rate is close to 500 000 t of zinc per annum. Graphite is the main gangue in the orebody and a substantial quantity of chemicals are used to achieve an acceptable depression of graphite and other gangue materials in the current operation. In the future, it is anticipated that the content of graphite in the orebody will increase while the zinc grade will gradually drop. This scenario illustrates the importance of an optimised suite of flotation chemicals to maximise concentrate grade and recovery. As an alternative to the current reagent suite where dextrin is used to depress graphite, laboratory test work and subsequent plant trials were conducted with alternative depressants. These depressants facilitated both graphite depression and elevated zinc grades in the rougher concentrate. As an added benefit, it was also observed that the silica content in the zinc concentrate was reduced in the presence of the biopolymer selected for the plant trials. Results from both laboratory tests and plant trials will be discussed to illustrate how this change of reagent suite improved flotation yield at the MMG Century Mine.CITATION:Wynn, R, Lauten, R A, Liang, H and Stoitis, N, 2014. A change in graphite depressant to improve the recovery of zinc at MMG Century mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 179–186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By Yan D. S

The removal of antimony from a refractory gold-bearing stibnite ore by roasting and selective chlorinating roasting was investigated. The influence of roasting temperature, roasting time, roasting atmosphere and type and amount of chlorinating agents on antimony removal were studied. The laboratory studies carried out included roasting tests of 4 g samples in a laboratory rotary kiln, followed by 400 g samples roasted in a fluidised bed. The test results revealed that antimony was efficiently removed by roasting at temperatures over 800¦C in a nitrogen atmosphere. The most efficient volatilisation of antimony was achieved with the addition of ferric chloride at temperatures between 350-600¦C.

Jan 1, 1995

By Kilgour I

The installation of a final cleaning column at Ok Tedi Mining Limited was carried out to increase final concentrate grade in order to reduce concentrate handling, shipping and treatment charges and to reduce penalty payments. To fast-track the project a decision was made to install a full-size column on one of the two parallel circuits, designed on information readily available and utilising the experience of mill staff and an engineering consultant, rather than delay installation while a pilot scale program was conducted. A 3.66 m diameter by 12.8 m high column was installed to produce 40 t/h of final concentrate from a combination of rougher concentrate and recleaner concentrate. The column design and sparger system were by Cominco Engineering Services Limited.

Jan 1, 1991

By Beck RW, Booth GW

Differences in the gold contents of sub-sample duplicates, derived from a single bulk sample are a function of analytical and random error, inhomogeneity within the bulk and natural variations in the distribution of particluate gold. By minimising bulk sample inhomogeneity and determining analytical precision, the residual natural variation may be modelled statistically to give an estimate of Bold particle sizes.

Jan 1, 1989

By Thompson D, Somerville JM, Brock DA

The development of a softwood alternative to the hardwood chockpiece used to build the waste-edge breakers commonly incorporated in gateroad packs is described. The results of laboratory tests on softwood prototypes and two underground trials are presented. The results of the last trial suggest that a viable alternative chockpiece has been designed, offering advantages over availability of wood, weight and given reduced wood content, price.

Jan 1, 1992

By Armstrong AB

It has been identified that particulate matter in the form of suspended solids and bed load has the ability to adsorb heavy metals. Each year Ranger Uranium Mines Pty Ltd (RUM) identifies potential danger areas which could become major sediment sources during the wet season. Methods of suppressing sediment uptake such as hydromulching and coating areas with Poly Vinyl Acetate (PVA) glue are used. Other methods of reducing the sediment load after uptake such as diversion bunds, filters across drains, stone filters, minor sumps and settling ponds are also used. The 1983/84 wet season saw drain sediment loads reduced to acceptable levels before the water reached the outside environment. Studies to qualify and quantify flows from minor drains are still underway.

Jan 1, 1984

Longwall mining in Australia is approaching maturity. Longwall production from 'state of the art' Australian longwall mines now rivals similar US based longwall operations. Regrettably however, Australian gate road development rates in general fall short of the required development to longwall production ratios that are required to sustain annual longwall production capabilities. By contrast, most US based longwall mines achieve the required development to longwall production ratios to sustain their longwalls. This is despite many having to drive three heading longwall panel gate headings to meet regulatory requirements.

Jan 1, 1998

Environmental considerations were key factors in the design of the Ranger Uranium Mines treatment plant. The mine is located adjacent to the Kakadu National Park and has an average rainfall of 1.6m per annum. Initially, no contaminated water or liquid effluents are to be released from the project area and thus water management is a key design and operating fact. Particulate and gas emission criteria influenced design as did occupational hygiene factors (dust, radon, housekeeping, maintenance access). Equipment selection and engineering standards were conservative and resulted in the plant attaining design performance in less than three months from the date of commissioning. A number of mechanical and operational problems were experienced and are discussed in the paper, however none of these problems have had a significant effect on production.

Jan 1, 1984

By Wasp E. J

A review is given of recent commercial long distance slurry pipeline systems in- stalled worldwide. The technological advan- ces in slurry engineering and system opera- tion are discussed, together with a brief re- view of the economics of slurry transportation and future trends in the industry.

Jan 1, 1973

By Mallett C

Coal mines are dynamic systems that change continually in size, shape, and condition. Large quantities of data about production, coal quality, ground stability, ventilation monitoring, equipment performance and location, vehicle and personnel movements and geology, are generated from all parts of the mine.Internet technology and virtual reality technology are now being combined to provide an intuitive, multi-dimensional information system which can simultaneously display any information that can be collected and stored by a computer. Physical information is directly displayed as 3-dimensional objects in the mine model. Numerical and text information is dynamically linked to these objects and accessed by "clicking" on them.

Jan 1, 1998

The paper considers the nature of outbursts of coal and firedamp as they occur. t follows the development of methods of working used to try and induce outbursts safely under controlled conditions and details the life support systems used to provide maximum rotection to persons who may be affected by s_lontaneous outbursts. Tilt: NATURE OF OUTBURSTS IN THE UNITED KINGDOM .1y some areas in the coalfields of the ingdom are affected by outbursts of :hal and firedamp. The main area affected is he western end of the Anthracite coalfield r: West Wales. In this area 206 outbursts .eve been recorded resulting in the loss of 8 lives. Anthracite is a high rank coal produced v the geological effects of age, depth and ynamic metamorphism. Outbursts have been xperienced over a wide area of the anthracite field but have been most frequent, and most evere, in the areas where carbon content is its highest and where the coal measures cave been subjected to the highest degree of eulting and overthrusting. Most outbursts ire associated with geological abnormalities ,:id the coal ejected during outbursts is sually of a soft and powdery nature.

Jan 1, 1980

By Paine GG

The Kidston Gold Mine commenced mining in 1984 and current annual production is 12 million tonnes, increasing in 1990 to 18 million tonnes. Mill throughout per year is 4 million tonnes with the balance of material being waste. The operation is a conventional hard rock open pit truck and shovel operation mining 12 metre benches. Buffer blasting is utilized to minimize post blast movement of the broken rock to maintain grade control.

Jan 1, 1988

Before presentIng my address I wish to acknowledge the honour which has been conferred on me by my appointment to the position of President of the Australasian Institute of Mining and Metallurgy.It is a matter of great concern to us all to find our Empire at war. I am confident that, as was the case in the war of 1914-1918, members of this Institute and of kindred Institutes and Associations will contribute in full to the Empire's needs and that in the end our cause shall triumph.I think it appropriate that I should take as the subject of my address that of the Broken Hill Lead-Silver-Zinc Industry. The subject matter of this address has been confined to the operations of Mining, Ore Dressing, Lead Smelting and Refining and production of Electrolytic Zinc in Australasia. The review of the Broken Hill Lead-SilverZinc Industry would not, of course, be complete without reference to those Australian industries which trace their origin to the Broken Hill field, but· it is thought that an outline of these industries would make thIs review too extensive.HISTORICALMany efforts have been made to translate the early history of Broken Hill and its subsequent growth throughout the years into one of the wor~d's most famous mining fields in the form of a simple story.

Jan 1, 1940