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By Benkendorff P. N

Cement production in Australia approximates 6.5 million tonnes per year. Cement clinker is sourced from 15 plants which operate 28 kilns. Cement grinding is conducted at 14 of the clinker plants plus 7 grinding plants. Average annual capacity per kiln or plant is lower than in many overseas countries, but kilns introduced since 1970's have been of larger size more in keeping with size trends overseas, although still smaller than the large units overseas. Substantial economies in capital and labour costs can be achieved in large production units, particularly with dry process kilns using precalcination techniques in which part of the fuel is introduced in the static preheater section ahead of the kiln while the balance is added to the kiln in a conventional manner. Precalcination techniques have been introduced to the Australian cement industry but as cement transport costs form a major part of supplying diverse market areas, the size of kilns is likely to remain less than maximum owing to balance with distribution costs. The cement industry uses significant amounts of thermal and electrical energy which can be minimised by proper selection of equipment and technology. Labour costs are also significant and can be contained by automation and computer control of the process.

Jan 1, 1989

The Significance of Internal Recycle in Froth Flotation

Sep 13, 2010

Research on Reduction-Magnetic Separation of Bayan Obo Ore

Sep 13, 2010

IN previous discussions on the occurrence of gold in the Bendigo quartz reefs the opinion has been put forward that the gold shoots are primary concentrations in the quartz reefs during the period of vein-formation. The view has been based upon the constant features of the gold shoots in a large number of individual reefs, independent of their depth below the surface. These features include the mineral associations accompanying the gold, the appearance and association of the gold in the quartz, the similarity in all respects (excepting mineral content) between richly gold-bearing quartz and poor quartz, and the variations in mineral content in the reef apart from gold. The view has been supported by a relation of the gold shoots to faults, together with the dependence of the reefs on the existence of pre-mineral faulting. The secondary deposition of gold has only been observed in a few instances .associated with the younger monchiquite dykes, and is of no economic importance.

Jan 1, 1922

By D Craw, D Falconer

The Morning Star mine is one of numerous historically mined gold-quartz lodes in the Preservation Inlet goldfield of southwest Fiordland. The mine is hosted in Early Ordovician metasedimentary rocks that are composed predominantly of psammitic and pelitic lithologies. These rocks still contain their primary depositional features and are characterised by upper greenschist facies metamorphic grade.   The Morning Star mine lies on the eastern limb of a gently south plunging anticline. A bedding parallel fault-vein and an associated network of minor quartz veins hosts mineralisation. The main fault-vein structure strikes N-NW, dips steeply (~60¦) W, has a strike length of ~350 m, a vertical extent of ~170 m and is up to 2 m in thickness. The internal structure of the fault-vein consists of laminated quartz, massive and fibrous quartz, and silicified breccias/cataclasites. Gold is typically coarse grained (~1 - 2 mm) and associated with pyrite, arsenopyrite, chalcopyrite, tetrahedrite and galena. The geometry of the Morning Star mine is similar in form to that of a saddle reef. Gold-quartz lodes in the Preservation Inlet goldfield are comparable in geometry and host rock to their offset equivalents in the Golden Blocks field of NW Nelson.

Jan 1, 2005

The Effect of Molecular Weight on the Adsorption and Efficacy of Polysaccharide Depressants

Sep 13, 2010

By M J. Andrews, P J. White, I Bogie

Active geothermal systems occur widely in Sumatra and in the Taupo Volcanic Zone (TVZ) ofNew Zealand. There are also many occurrences of epithermal gold mineralisation in Sumatra, some of which are economic. Minor sub-economic occurrences of gold have been reported in the TVZ but none have yet been mined. There are both similarities and differences in the nature of the active geothermal systems and mineral deposits in Sumatra and New Zealand, which can be systematically related to the tectonic setting. The thicker crust and consequent predominance of silicic volcanism in New Zealand leads to hydrothermal systems which are little eroded and with limited lateral outflows. The systems in Sumatra are of mixed character, with some of the characteristics of those in andesitic island arcs such as Java or the Philippines, e.g. a higher proportion of systems with identifiable acid magmatic volatiles, a greater potential for deep erosion and lateral outflows than in New Zealand; but modified by the more oblique component of subduction and thickened crust so that some are localised in volcano-tectonic depressions and consequently have high piezometric levels of primary hydrothermal fluid. The unusual occurrence of calcic zeolites in veins associated with gold mineralisation in Sumatra is thought to be indicative of æsatelliteÆ boiling zones along de-gassed hydrothermal outflows.

Jan 1, 1995

By M J. Begbie, K B. Sporle

The Golden Cross low sulfidation epithermal deposit produced approximately 750,000 ounces of Au from two ore zones: the underground Empire Vein System and the open pit stockwork. The Empire Vein System has at least eight stages of vein formation: (1) sulfide veins, (2) black veins, (3) massive veins, (4) banded veins, (5) thin white veins, (6) crumbly veins, (7) massive/platy calcite veins, and (8) flattened rhomb calcite veins. Gold mineralisation occurred relatively early in the lifetime of the system, dominantly during 2 through 4. The late calcite veins (7 and 8) and early sulfide veins (1) are barren. The vein system formed in a dominantly extensional environment, though some compressional faulting may have also existed during vein formation. There is no evidence for significant strike-slip faulting during vein formation, highlighting the fact that explorationists should pursue on-site structural patterns rather than fashionable models.

Jan 1, 1998

In several of the States of Australia, mining on private property has been seriously hampered by the fact that large areas of land have been alienated from the Crown before the discovery of gold or other minerals. In Western Australia this difficultyhas only occurred to a small extent, and has largely been overcome by an act entituled "An Act to Permit Mining on Private Property, No. XXIX., 'October, 28th, 1898." Under this act, the holder of a miner's right can apply for a gold mining lease on private land; such applicant may treat privately with the owner of such land as to the amount of compensation to be paid for surface ,damage, or the case may be brought before the Warden who will assess the damages. Private land used as a garden, orchard, or vineyard is exempt from lease, unless the applicant has authority from the owner, or such lease is limited to a greater depth than 100 feet from the lowest part of the surface.No lease shall be granted of any mines under any private land in any municipality unless either the applicant has authority from the owner, or such lease is limited to a greater depth than two hundred feet from the lowest part of the surface.The same regulation applies to leases of private land on which any hospital, asylum, or public building is situated or under or within one hundred and fifty yards laterally of any...

Jan 1, 1901

My speech this morning is not a technical one, rather I will aim to tell you about the New Zealand Aluminium Smelters Limited and how I see it fitting into the Western World aluminium scene.

Jan 1, 1983

By G Mark, K L. Blake, G de Jong, J F. Rotherham, N D. Adshead

Magnetite deposits with distinctive ¦ actinolite ¦ apatite-bearing gangue and spatially-extensive sodic-calcic wall rock alteration occur in both Proterozoic metamorphic terrains and Mesozoic-Tertiary magmatic arcs. Examples from both settings constitute significant sources of iron ore (egKiruna, Sweden; El Romeral, Chile) and some host major Cu-Au deposits that have a local association with K-silicate alteration (eg Cloncurry district, NW Queensland; Copiapo district, Chile). A growing body of evidence points to a hydrothermal origin for these systems involving high temperature, low S oxidised fluids. The Cloncurry magnetite-Cu-Au deposits are products of the local structurally channelised influx of a specialised high salinity ore fluid into larger-scale alteration systems developed during pluton emplacement at greater depths than those associated with subvolcanic (porphyry) Cu-Au deposits. The geological characteristics of deposits in magmatic arcs are consistent with a similar mode of origin albeit in rather different tectonic settings.

Jan 1, 1995

By J Wesseloo and Y Kim, Y Potvin, G Mungur, D Grant

At the previous MassMin conference held in Sudbury in 2012, the authors proposed a new framework going beyond dilution and equivalent linear overbreak sloughing (ELOS) for stope reconciliation in relation to the planned stope design. More specifically, the new process investigates performance outcomes including rock overbreak (OB) and fill overbreak (FOB), rock underbreak (UB) as well as geomechanical and operational aspects such as blasting, fragmentation and other production data.Based on the findings of the original 2012 study, a comprehensive data gathering program has been undertaken involving design and reconciliation data from 43 stopes mined between September 2012 and October 2014 at BHP Billiton’s Olympic Dam (OD) operation. The new database structure was based on four types of data:stope definition and performance datastope geometrygeotechnical parametersoperational parameters.The new database allows a more in-depth investigation of stope performance. It is now possible to quantify and analyse UB and OB performance from each wall individually as well as the crown. In this paper, the influence of several parameters on recent stope performance at OD is analysed. The underlying reasons for stope wall performance outcomes are discussed in this paper.CITATION:Potvin, Y, Grant, D, Mungur, G, Wesseloo, J and Kim, Y, 2016. Practical stope reconciliation in large-scale operations part 2, Olympic Dam, South Australia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 501–510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

The mineralogy of the rocks now observed in the Nairne pyrite deposit developed under conditions of internally-controlled sulphur activity during amphibolite facies metamorphism. In the sulphide-deficient metasediments the activity of sulphur was low, and pyrrhotite developed with iron-bearing silicate minerals. At higher sulphur activity, in the sulphide-rich meta-sediments, pyrite formed in addition to pyrrhotite, and the associated silicate minerals are iron-deficient.

Jan 1, 1969

THE Talisman mine is situated on the Waitawheta (pronounced Wytaffetta) river just above its junction with the Chinemuri (pronounced Chinnemurre) river near Karangahake, NZ. The explored reef-bearing portion of the claim includes the angleformed by the junction of the rivers and extends southwards for slightly over a mile (See Plate V.). The country is mountainous both rivers flowing through precipitous gorges.The trig. station on Karangahake mountain is almost directly above the workings on the Bonanza section and is 1680 ft. above river level, the adit from the gorge giving 1200 ft. of backs measured vertically. The officers of the N.Z. Geological Survey are engaged in a detailed survey of the Waihi district and the rocks of Karangahake are under examination. The rocks of the district are andesites and dacites much altered and silicified. One of these exhibits a columnar structure in the mass in the Waitawheta gorge near the surface workings on Taukani hill, also on the southern bank...

Jan 1, 1912

The history of zinc production in Australia is outlined including attempts to make zinc electrolytically at Cockle Creek, N.S.W. in the last century, the use of horizontal retorts at Cockle Creek and Port Pirie, South Australia, production by electrolysis at Risdon, Tasmania and at Port Pirie using zinc oxide fumed from lead blast furnace slag and production by the Imperial Smelting process at Cockle Creek. Developments in the electrolytic process are described including those in roasting, acid manufacture, leaching, purification, electrolysis, melting and casting. The Imperial Smelting process technology is also outlined. In both processes global technology is reviewed, including important Australian contributions.

Jan 1, 1986

Rational decision making is generally perceived by managers of operations to be a delicate process of committing large sums of money and putting other people's life at risk. Consequently most managers may argue that the decision process requires good judgement, intuition and extreme caution; and not one easily made through the use of fancy mathematical algorithms and computer programs. The advent of artificial intelligence and expert systems in the computer industry combined with recent technological innovations in mathematical and economic problem solving is sure to change this perception. PARETO OPTIMALITY is an economic and a mathematical optimisation concept applied to solving real life operational problems; and one that the current volatile economic forces would require managers to employ because it is virtually real. REALISMM is a computer software package developed using the principles of Pareto optimality, dynamic programming, optimal clustering of information and decision maker interaction to generate decision maker preferred solutions. REALISMM has scope for artificial intelligence and expert systems application for cases where the decision maker is unsure about his objective preferences.

Jan 1, 1993

By G R. Hancock, S Grant, T Whiteside, J B. C Lowry, J Boyden, T J. Coulthard

Physically-based landform evolution models (LEM) provide a spatial framework to forecast the long-term geomorphic stability of post-mining landscapes. When used to test the relative stability of different landform designs, LEMs may assist with the development of optimal closure designs for rehabilitated mines. However, in order to reduce prediction error, factors controlling landscape evolution must also be accurately represented by models. This requires that the correct sets of processes are represented and that driving parameters used in LEMs are, if necessary, calibrated to the landscape of interest.Vegetation exerts strong controls on the hydrologic and geomorphic processes that drive landscape evolution. Hence, the spatial and temporal scales over which typical patterns in vegetation are represented in different landscapes are important considerations in LEM calibration. However, vegetation is rarely accounted for in LEMs and even when integrated is often represented simply, without representing spatial dynamics of vegetation cover that may impact landform development.This study focuses on characterising vegetation patterns to calibrate a new vegetation module of the The Cellular Automaton Evolutionary Slope and River (CAESAR)-Lisflood LEM to be applied to a conceptual rehabilitated landform of the Ranger uranium mine located in the Alligator Rivers Region (ARR) of northern Australia. In the ARR the spatial dynamics of vegetation over time are largely driven by monsoonal rains and topography. Extensive dry season fires are also common in the region, temporarily reducing vegetation cover where they occur. Hence, hydrology, topography and fire disturbance interact to shape a distinct, yet dynamic, mosaic of different vegetation types of varying cover density. As a basis for calibrating the new vegetation function, the distribution and dynamics of vegetation are characterised for this savannah landscape by remote sensing, in conjunction with ground data.CITATION:Boyden, J, Lowry, J, Coulthard, T, Whiteside, T, Hancock, G and Grant, S, 2016. Accounting for vegetation dynamics in landform evolution modelling, in Proceedings Life-of-Mine 2016 Conference , pp 63–66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By the use of flotation tests it was confirmed that there are two functions of oxygen in sulphide mineral flotation. Sized samples of galena and chalcopyrite were sulphidized, washed free of excess sulphide ion, and then contacted with air-saturated water for certain lengths of time. The mineral was then transferred to a sealed laboratory flotation cell containing water with a known concentration of dissolved oxygen. Xanthate and frother were added and flotation continued for 1 min.Both the extent of mineral oxidation and the concentration of dissolved oxygen markedly affected the flotation of galena and chalcopyrite. The response to a change in either variable is dependent on the level of the other, but generally best flotation occurs with the maximum degree of air saturation of the pulp. Galena flotation is hindered by oxidation of the mineral beyond a small threshold amount but a similar effect for chalcopyrite was not observed...

Jan 1, 1967

THE North Mount Lyell Mine is situated on the southern side of Mount Lyell at an altitude of 1750 ft. above sea-level. The average rainfall is 117 in., and there are generally several light falls of snow during the year. Despite the heavy rainfall, which is fairly evenly distributed over each of the twelve months, the climate is equable and not unduly rigorous, and, provided that the mine employee is suitably clad, it is only on exceptional days that he experiences any discomfort by becoming wet journeying to and from the mine.The majority of employes reside at Queenstown, and are conveyed by special trains to and from the top of the haulage, which is less than a mile from the mine. The mean surface temperature at the mine is 46° F., with a maximum variation from 26° F. to 85° F., the relative humidity generally being higher than in other districts. The rock temperature is 48° F. on the 200-ft. or Main Adit level, and 54° F, on the 1200-ft. level, giving a rise of 6° F. for 1000 ft. in depth.The ventilation of the mine is natural, the downcast being served by the Crown and Blocks shafts and the Crown mullock pass, and the upcast air is carried away from the workings by the Main shaft and the Nos. 1 and 2 mullock passes. The quantity of air circulating varies from 25,000 cub. ft. to 35,000 cub. ft. per minute, the greater quantity moving in the colder weather. The downcast air in traversing the wet shafts becomes saturated and enters the level at the rock temperature of 54° F. in winter and about 56° F. in summer, while temperature readings of the outcast air indicate that it varies very little.In the southern end of the mine the Blocks shaft downcast air upcasts through the different stopes, and their mullock passes, to the level above for each level to the 700-ft. level, where it passes to one of the main uptakes. The prown shaft downcast air supplies...

Jan 1, 1927

By C S. Szentesy, K Howie

The Rosia Montana gold deposit is located within the æGolden QuadrilateralÆ area in the Apuseni Mountains of Transylvania, Romania. The deposit is situated approximately 85 kilometres north of the regional centre of Deva, within the province of Alba, at elevations of up to 1100 metres above sea level. The Rosia Montana deposit contains a current resource of 344.07 million tonnes at an average grade of 1.3 grams per tonne (g/t) gold (Au) and 6.0 g/t silver (Ag) for a total (measured, indicated and inferred) contained resource of 14.29 million ounces of gold and 67.00 million ounces of silver. The resource was calculated using a 0.6g/t Au cut-off, a 10 x 10 x 10 metre block size and multiple indicator kriging. The low sulfidation style epithermal mineralisation at Rosia Montana is hosted within Tertiary age dacite intrusions and related vent breccias. Mineralisation is generally disseminated and associated with silica, adularia, illite, pyrite and carbonate alteration of host rocks, with minor late carbonate-base metal veins. Precipitation of precious metals is generally considered to have occurred as a result of over-pressurization, boiling and subsequent brecciation. The dacite intrusions are hosted in Cretaceous shallow marine and deltaic shales and slates, which overlie older Paleozoic sedimentary and metamorphic rocks within uplifted sections of oceanic sea floor.

Jan 1, 2002