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By L Strezov, J Herbertson

Conversion of industrial waste materials to valuable resources would essentially take part in an ecologically sustainable future. There are still large amounts of undervalued biomass wastes generated from a diverse range of industries that are disposed in landfields. They have potential to produce valuable materials and fuels, such as charcoal, bio-oils and bio-gas through thermal upgrading. In order to enhance the efficiency of the thermal upgrading process, comprehensive characterisation of the raw biomass materials is essential. We have developed a novel thermal characterisation method that utilises computer aided thermal analysis incorporated with a gas analyser. The method was applied on two biomass materials, wood sawdust and bagasse. The paper discusses the results obtained with the novel thermal characterisation technique.

Jan 1, 2006

People in the work environment (and often elsewhere) are seen as a commodity (we use them for our purposes).The general accepted view of a Company is that shareholders are "The Company" and that they employ people to utilise their money in a particular field to generate more money to give a return on investment. To achieve this, capital equipment is purchased to fulfil a task and people are employed to use this equipment. Equipment and people are commodities purchased with money.The focus of this approach is MONEY. The equipment and people, and the use of them, determines the amount of money that can be generated. In this approach people are motivated by financial concerns. The harder the times the more money becomes the focus.

Jan 1, 1998

Industrial minerals and rocks (alternat ively called non-metallic minerals) are those- which are economically important because of their desirable physical or chemical properties rather than their metal or energy content. They are divided into nine classes: structural, pig- ments, process aids, ceramics and refractories, chemical source minerals, abrasives, foundry minerals, gem stones, electrical minerals. Development of deposits is influenced by the dominance of marketing,by the required range of products, the-need for specialized process- ing, place value, and the transportation and distribution of high-bulk, low-cost commodities. Evaluation is different from that of base metals because of differences in geological occurrence, sampling methods, testing, treatment, placing a money-value on the material and the importance of export markets.

Jan 1, 1973

By Golding D

The Charters Towers goldfield is located in the centre of a Lower to Mid-Palaeozoic igneous complex where schistose, amphibolite-grade metamorphic rocks were intruded by multiple phases of medium grained granodioritic rocks. Several generations of mafic and felsic dykes also occur. Two distinct mylonites cut all but the youngest granitoids. Gold mineralisation occurs in quartz veins located in brittley reactivated mylonite and in sympathetic fissures in the undeformed granitoids. The gold-quartz veins occur in complex, gouge-filled, 2.5m thick zones, with minor sulfides, surrounded by zoned phyllic and propylitic alteration assemblages. Four main vein systems are each restricted to separate granitoids or contain oreshoots near granitoid contacts. No genetic relationship between the granitoids and the vein systems can be documented. The early mylonitic fabrics and the granitoid contacts played an important role in ground preparation and in the localization of oreshoots. Non mylonitized granitoids also served as favourable hosts for many of the lodes. Whole rock values of 180 of the granitoids range between 6.5 and 7.9 per mil. Hydrothermal vein quartzes have 180 values between 12.2 and 15.7 per mil. Mylonite quartzes have values of 8.4 per mil. Variation in 180 values of quartzes is in part related to granitoid host rock type.

Jan 1, 1987

Does coal mining get enough out of its people?. In a number of cases, Yes. Several companies have rethought their management systems and accordingly are improving their utilisation of people to improve productivity. For some, capital and technology are the panacea for improved productivity and lower costs. Computerised mine planning, improved beneficiation processes, heftier longwall equipment, bigger trucks and shovels and upgraded coal clearance systems are expected to provide the answers.Whilst these factors are important they only contribute to part of the productive potential of a mining operation. Production flexibility provided by recent Industry award changes has brought about increases in total output. However, these improvements have not been matched by corresponding decreases in the unit cost of production.

Jan 1, 1991

By Heinrich CA, Wall VJ, Walshe JL

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

One of the most praninent Bouguer anomaly features in the Broken Hill District is the long wavelength high of 10-15 ngals above background which forms a northeast trending, oval zone sane 15 km by 45 km with Broken Hill on its northern gradient. Rock density measurements and modelling indicate that this anomaly can be explained by the presence of generally relatively higher density meta- sediments extending from the surface to a depth of about 2000 m. The regional Bouguer anomaly data show that the Willyama Block and Euriowie Block are mostly overlain by a fairly smooth Bouguer anomaly high in the range 5-15 mgals, whilst the surrounding younger sediment covered areas, including the Mundi Mundi Plain, Murray Basin fringe and Bancannia Trough, are mostly overlain by lows which range to minus 30 mgals. Thus in terms of the gravity pattern the Willyama and Euriowie Blocks form a fairly continuous and haogeneous entity. However, the 5-10 mgals relative low over part of the Torrowangee Synclinorial Zone indicates that the Adelaidean System metasediments are in aggregate slightly less dense than the Willyama Supergroup metasediments. The low can be modelled to indicate a basement link between the Broken Hill and Euriowie Blocks at 1000-2000 m depth.

Jan 1, 1983

By N Lima, A Piçarra, L Filippov, I Filippova, M Marques, K Silva

The iron industry produces a considerable amount of tailings per annum, due to its substantial volumes of production. The actual iron ore processing routes require the removal of slimes fractions. In addition to iron oxides and quartz, the iron ore slimes are generally composed of other minerals such as kaolinite and finely dispersed iron hydroxides which impact significantly the performance of reverse cationic flotation. In this study, we propose a two stage processing route that would allow further beneficiation of iron slimes which are not successfully beneficiated, avoiding their disposal as waste. The new amidoamine reagent was tested as a collector in a two-stage route to process two samples of iron ore slimes with d50 close to 10 μm and with high kaolinite content (13 to 20 per cent). The results showed that it was possible to obtain iron concentrate with 66.5 per cent iron and 48.4 per cent mass recovery for a feed containing 48.9 per cent Fe associated with hematite (39 per cent) and goethite (32 per cent). The collector efficiency was improved by mixing with frother for the slimes with higher goethite content of 55 per cent: the concentrate grade was increased from 58.8 per cent to 64.5 per cent with addition of the frother at the expense of reducing operation metallurgical recovery from 87.8 per cent to 75.6 per cent. The efficiency of the process was improved by applying an external energy impact to disperse the fine particles and clean the surface of the minerals. The new amidoamine collector does not require a depressor such as corn starch and may provide the development of new concentration routes for complex ultrafine iron ores. The combination of the amidoamine-based flotation at first stage with high intensity magnetic separation allowed development of optimised two-stage processing routes to valorise the iron ore slimes rejected to the tailings in the actual flotation plant.

Sep 18, 2023

Flue gases from electrical power station boilers, roasting, metallurgical and chemical plants could be treated by flotation using conventional flotation machines. The flue gases are introduced into the pulp instead of the air. The flotation media is a suspension of Ca(OH)2 or CaCO3 or a solution of NH4OH etc containing Na oleate as collector and frother. The SO2 and dust content of the initial flue gases were experimentally reduced by 100 to 1000 times in one flotation operation. The velocity of the flue gases through flotation machines could reach approximatively 0.4 to 0.5 m/s and more against 1.5 m/s reached in scrubber absorbers used for this purpose, but the quality of purification is expected to be better for flotation, which is essential for the cases of heavy polluted metallurgical and chemical flue gases. For some chemical plants the flue gases flotation media may be different and more suitable as compared to the above mentioned media. The proposed flotation method could be used for separation of dry grinded ores in the form of aerosols, with a realisation of flotation from a closed space (gas bubble in the pulp) onto the interface liquid-air where the particles are attached inside the bubbles.

Jan 1, 1993

By Jackson E

The general level of awareness amongst members of the professions that they are faced with an increasing number of claims for breaches of their professional duty was dramatically heightened by the decision of Rogers J. at first instance in Cambridge Credit Corporation v Hutcheson (1985) 3 ACLR when the auditors of the failed company were found liable for breach of contract and faced a damages award of $145 million - well in excess of their insurance cover. No comfort should be found in the fact that this decision was overturned on appeal, for that result rested on the issue of whether there had been a causal connection between the breach of contract which had occurred and the loss suffered rather than on the fundamental principle of auditors' liability.

Jan 1, 1989

By C Rule

In 2003, Anglo Platinum, in a joint development with Xstrata Technology, installed the world’s first 10 000 litre IsaMillTM in a concentrate regrind duty at the Western Limb Tailings Re-treatment Plant. The success of that installation was the enabling event for Anglo Platinum to proceed with a substantial investment in horizontal stirred milling technology. Since 2006 an additional three IsaMillsTM in concentrate regrind duties and a further 18 IsaMillsTM in the more technically challenging coarse grinding mainstream applications, have been commissioned in group Concentrator operations - bringing the total number of IsaMillsTM installed in Anglo Platinum plants to 22.A collaborative approach between Anglo Platinum and Xstrata Technology towards improving milling efficiency and reducing operating costs, through internal mill component wear optimization and operating recipe development, has resulted in further improvements in the overall success of IsaMillsTM in the flow sheets of many Anglo Platinum operations. The addition of IsaMillsTM in the Anglo Platinum flow sheets has improved plant PGM recoveries by as much as 5%.This paper explores the improvements made to the IsaMillsTM flow sheet and mill internal design and shares some of the operating experience with IsaMillsTM technology in Anglo Platinum

Aug 8, 2011

The ore mined from the Lead Lode of The Zinc Corporation leases consists of a fairly granular mixture of galena, marmatite, chalcopyrite, tetrahedrite, pyrrhotite, pyrite, and lollingite with a gangue association of calcite, quartz, bustamite, rhodonite, mangan-hedenbergite, garnet, fluorite, mangano-calcite and apatite. The silver content of the ore occurs in three minerals tetrahedrite, dyscrasite, and pyrargyrite, the last two mentioned occurring in microscopic association only. Other metallic and gangue minerals are also present in this complex mineralogical association, but do not influence the milling operations.Fortunately, the silver minerals favour the galena and chalcopyrite as their host minerals, thus facilitating the recovery of both copper and silver in the lead concentrate. The ore from the Lead Lode assays from 14 - 18 per cent lead; 3.0 - 4.5 oz silver per tonne, and 9.5 - 12.0 per cent zinc.A parallel lode, known as the Zinc Lode, is well developed in The Zinc Corporation leases. This lode assays from six to eight per cent lead, 1.5 oz silver per ton, 18 - 25 per cent zinc with a siliceous gangue. The common Lead Lode gangue minerals, calcite, rhodonite, bustamite - are very rare in present underground exposures. No metallurgical work was done on this ore during the pilot plant operations.The aim in the milling process is to produce:1. A lead concentrate with the maximum economic recovery of lead, silver, gold, copper and antimony, and minimum zinc content.2. A zinc concentrate with the maximum economic recovery of zinc, cadmium, and cobalt, and minimum iron, arsenic and fluorine content.3. A waste residue containing sufftcient granular material to be utilised as underground fill.In considering the economics of the milling practice the above three requirements plus consideration of the tariffs submitted by the purchasers of concentrates were the deciding factors in the evolution of the present milling practice.Towards the end of 1924 The Zinc Corporation Limited added to and adapted the old zinc tailings plant for the treatment of 5000 tons of crude ore per week. This plant, which operated until January 1936, was in general principles similar to the standard Broken Hill methods of ore concentration, whereby the galena was recovered by the gravity concentration methods of jigging and tabling with selective flotation concentration of the residual galena and marmatite. One important difference from other Broken Hill plants was that the primary grinding of the jig tailing was performed with flint-loaded mills operating in closed circuit with revolving screens. Two primary grinding sections were installed, each consisting of two 5 ft diameter by 10ft long tube mills loaded with flint pebbles working in closed circuit with four 3 ft diameter by 3 ft wide revolving screens covered with 22mesh Toncap woven wire screen with 0.57 mm opening. Each section carried a circulating load of 28.3 tons per hour for a jig.

Jan 1, 1994

By M Angus, S Konopa, A Virisheff, S Crispin

A positive mill reconciliation at a mine is a double-edged-sword. Much back slapping happens. The bank and the board can’t get enough until the downside becomes apparent. Over a prolonged period, there becomes an issue with market perception and the potential for shareholders to be misinformed regarding the potential value of the project. In addition, there are impacts on mine scheduling, waste allocation (or lack thereof), government expectations, and the potential for misguided external assumptions regarding the ‘unexpected’ results. The PT Agincourt Resources Martabe Gold Mine has shown a significant under-call, in the order of 20% total gold metal, between the Mineral Resource (MR) estimates and Grade Control (GC) estimates since production commenced in 2012. Recently, the under-call has been reduced by incorporating the use of grade control drilling in the MR grade estimates. Despite recent improvements in reconciliation, drilling in 2017 at both Purnama and Barani open pits shows that infill reverse circulation (RC) drill holes often produce significantly higher grades than those predicted in the MR block model. CITATION: Angus, M, Virisheff, A, Konopa, S and Crispin, S, 2018. Martabe Gold Mine, Indonesia: a positive solution for positive reconciliation, in Proceedings Complex Orebodies Conference 2018, pp 76–78 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Linge H. G

The effect of sodium pyrophosphate and several polyacrylate deflocculants (Freevis 502, 528, 529 and 532; and Maxfloc 1015) on the gold loading on Calgon GRC22 and Norit R035l5 carbons was tested and found to be insignificant in a pulp free enviroument. These deflocculants can therefore be used in plants processing viscous gold pulps without fear of fouling the carbon.

Jan 1, 1990

By Edwards A. B

Yampi Sound is a small channel in the Buccaneer Archapelago (latitude 16° 10' S.; longitude 123° 40' E.), on the northern coast of Western Australia (Fig. 1), about 90 miles north of Derby, and 200 miles north-east of Broome.The iron ore deposits of Yampi Sound occur on an approximately S.E.-N.W. trending belt of islands which form the northern boundary of the Sound (Fig. 2). From east to west they are Koolan Island, Tarrant Island, Usborne Island, Cockatoo Island, Irvine Island, Kathleen Island, Flora Island, and Bathurst Island. To the south of the Sound lie Margaret Island, which is separated from the mainland by a channel only 60 ft. wide, Dorothy Island, and Gibbings Island. Some of the channels between the...

Jan 1, 1938

By Thiel D. V

It is quite well known, although not so well documented, that radio noise is generated during rock fracture. Radio noise has also been observed during severe earthquakes. The source has been thought to be the fracturing of the rock, although the mechanism has never been unequivocably proven. A study of these radio emissions may provide insight into rock dynamics prior to seismic events, and after blasting. A programme of electric-field recordings has been undertaken at Brisbane quarries during multi-hole blasting. Preliminary analysis has shown that three types of signal may be distinguished. They are hole detonation, rock fall and post blast relaxation signals. It is thought that information about the blast, and the fracture of the rock, may be ascertained from these Signals.

Jan 1, 1990

By S Ellis

In January 2008 Chirano Gold Mines Limited committed to expansion of the Chirano Gold Project from its existing design capacity of 2 Mtpa ROM ore to a new design value of 3.5 Mtpa. In addition to increased throughput, the design had to contend with increasing ore hardness and competency, while at the same time make cost effective use of existing equipment with minimum disruption to existing production. The solution adopted involved some novel approaches including tertiary crushing and operation of the SABC circuit in overflow ball mill mode and parallel elution with a common acid wash column. This paper describes the approach taken to the design of these elements to achieve a cost effective and safe capacity expansion.

Aug 8, 2011

By Matsuhisa Y, Sakurai W, Shimazaki H, Peiming H, Fukahori Y

Oxygen and carbon isotope mapping of hydrothermally altered wall rocks was applied to the blind ore prospecting of skam Pb-Zn deposits in the Kamioka mining district, central Japan, where the wall rocks consist of heterogeneous rock units. The results (8180sMow of -1.1 to +17.3%o and 613CPDB of -5.0 to +4.8%o for limestones, and 8180SMOW of -0.8 to +12.5%c for silicate rocks) show isotope zonations of the wall rocks with depletions in heavy isotopes (180 and 13C) toward the center of mineralization. The isotope zonations likely formed by interaction of migrating thermal waters with the wall rocks during the mineralization. The heavy-isotope depleted zone, which indicates higher temperature or higher water-to- rock ratio of the system, occurs in the footwall of a fault, indicating that the fault played the role of main conduit of the ore-forming fluids. A heavy-isotope depleted zone was also found in an area, where significant mineralization had yet to be identified. Recent drilling in this area has intercepted a zone with a grade of 16.0% Zn, 0.8% Pb, and 35g Ag per metric tonne at a depth of about 360m.

Jan 1, 1995

By D J. Williams, A Shokouhi, A Naderian

Extracting alumina from bauxite involves the production of fine-grained waste known as red mud. The highly alkaline red mud is usually neutralised by applying sea water, thickened to between 25% and 30% solids by mass, before disposal to a Tailing Storage Facility (TSF). Hydraulic sorting, settling, self-weight consolidation, and desiccation are the processes contributing to the overall volume change of the red mud after deposition. Investigating the effect of these processes on the volume change behaviour of the fine-grained red mud is an important step in the estimation of the required storage volume of the storage facilities. This paper presents the results of a series of laboratory consolidation tests in a slurry consolidometer, and comparisons are made with field testing and observations.CITATION:Shokouhi, A, Naderian, A and Williams, D J, 2018. Assessing the volume change behaviour of red mud through laboratory and field testing, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 309–316 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

Despite extensive oil exploration in"Western Australia over the past 12 years no commercial oil fields have yet been found. A total ' of 66 test wells have been drilled throughout the State but only Rough Range No.s.. 1 and 1A have produced oil in significant quantities. Active oil exploration is now in progress in the" Canning, Carnarvon, Perth, Bonaparte Gulf and Officer Basins. Test wells have been drilled' in ,all of these except the Officer Basin, where the subsurface stratigraphy is still unknown. Large .areas of the other four have hot yet been drilled. It, is- probable that. commercial oil deposits will eventually be found' in these basins as they contain thick marine sequences, and have structures 'suitable for.,the. entrapment of oil. .

Jan 1, 1964