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By M Ruhrberg, J Grassmann, C Bauer

Within the context of acid mine drainage (AMD) associated with mining activities worldwide there has been a tremendous research effort to determine the extent of AMD and assess the influencing factors controlling this process. However, the majority of the current approaches focus on local and regional scale case studies and do not provide a global scale picture of AMD potentials. This study attempts to develop a method aiming at a global environmental impact assessment related to AMD. To confine the complex topic this study concentrates on acidic emissions from heaps in consequence of copper mining processes. In order to pursue this approach two factors are of significant advantage: a comprehensive environmental data base of more then 600 copper sites worldwide and a method which has been developed and proven to be successful in assessing environmental impacts related to land use. Current and future research efforts focus on using this background knowledge to enable both a comparison between sites and a categorisation of sites according to emission estimates.

Jan 1, 2003

Major exploration companies can have a problem with what to do with small precious metal ore bodies located through exploration programmes. Low tonnage, but high grade, ore bodies too small to justify in-house development.1.2 Ban Ban Mining is a Sunshine Coast based partnership with considerable expertise in mining and earthmoving which specializes in the mining of small/medium size ore bodies on behalf of the tenement holder on a profit sharing or royalty basis.1.3 The partnership's first successful venture has been the mining and vat leaching of a small 40,000 tonne ore body with a head grade of 5 gm/tonne gold and 32 gms/tonne silver, situated near Ban Ban Springs in southeast Queensland.1.4 This paper looks at the low cost vat leaching method of treatment, as an alternative to CIP and CIL in the processing of low tonnage/high grade precious metal ore bodies.

Jan 1, 1990

By S Planeta

The use of explosives in underground mining has its drawbacks, particularly in the case of thin or narrow vein type deposits. Due to that, there is a need to develop more discriminative and safe rock-breaking technologies. Mechanical rock splitting seems to be one of the most promising avenues in this respect. This paper describes briefly principles and features of radial-axial splitters. It reviews a feasibility study done to evaluate a potential of this technology in selective mining. It was intended to compare productivity and cost of ædrill-splitÆ mining with conventional cut-and-fill method. Hypotheses and assumptions adopted, methodology used and the obtained results are presented and discussed. The study has confirmed an interesting potential of radial-axial splitters in mining thin and narrow vein deposits. In conclusion, it is stressed however, that it will take more R&D work to corroborate the results obtained. Some suggestions concerning future research in this field are also given.

Jan 1, 2003

By Munive L

As a result of commissioning No.5 B F, 2670m3 inner volume, in March 1972, the largest B F in Australia; new expertise in maintenance, furnace operating practices and design have been obtained. This experience has also been extended to the other furnaces. A series of operating problems were con- fronted; all parts of the furnace, including the hearth side walls and bottom,were adversely affected. In December 1977, serious hearth wall wear was detected at No.5 B F, and a potential hearth breakout was averted. Hearth wear in No.4 B F was discovered in March 1979, and emer- gency underhearth cooling was installed to reverse an extremely advanced hearth bottom erosion. Hearth behaviour of No.5 B F oampaign 1972-1978 and`No.4 B F campaign commencing 1972, has been studied and discussions on the causes, effects and measures undertaken to protect the hearths are presented in this paper.

Jan 1, 1981

By J Addai-Mensah, M Adam, W Skinner, J Begelhole, K Quast

Granulation of iron ore fines into robust granules is critical to successful sintering and blast furnace operations in iron and steelmaking. Iron and steelmakers desire iron ore granules with high strength, uniform size distribution and low fuel consumption to enhance efficient sintering operation. Unlike hematite ore, magnetite concentrates do not granulate easily at low binder dosage to yield coarser granules due to the absence of nucleus particles. This motivates the present study to harness the complementary properties of hematite ore to enhance granulation of magnetite concentrates via blending. The current state-of-the-art in hematite and magnetite blend granulation is reviewed, along with granule property limitations. Preliminary experimental work on granulation of hematite and magnetite blends as a precursor to sintering is reported.CITATION:Adam, M, Addai-Mensah, J, Begelhole, J, Quast, K and Skinner, W, 2017. Enhancing magnetite concentrate granulation by blending with hematite ore, in Proceedings Iron Ore 2017, pp 17–24 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Gillies A. D S, Lee A. H

Water is an integral component of a mining operation. To-date water management has received a low profile in the overall management of mining operations. To cost effectively meet the requirements of government environmental legislation the man

Jan 1, 1994

By T C. Hunter

There are unique risk factors involved in the development of an Australian uranium project especially by a æjuniorÆ. These encompass a range of political, technical, environmental, regulatory, timing, native title, investor relations and financial issues. The Honeymoon Uranium Project in South Australia is being developed by Southern Cross Resources. The history and experience from a risk viewpoint is detailed and discussed. Particular emphasis is placed upon the practical experience and obstacles overcome to meet project milestones.

Jan 1, 2003

Peko Mines N.L. has considerable experience in the treatment of a wide range of comparatively small orebodies.Gold-silver, bismuth, and sulphide and oxide copper ores are treated under difficult geographical conditions.Treatment of these ores is complicated by some unusual metallurgical factors.Metallurgical operations are described, including the treatment of the gold-bismuth-copper ore from Juno. The new Warrego mine is to have a highly instrumented concentrator by December 1971. Autogenous grinding is being considered.

Jan 1, 1969

By E ¦iftti, A Koenig

Natural sphalerite associated with copper, silver, lead-zinc, tin and tungsten deposits from various world-famous mineral deposits have been studied by cathodoluminescence (CL), laser ablasion inductively coupled plasma mass spectrometry (LA-ICP-MS), electron probe microanalysis (EPMA) and electron paramagnetic resonance (EPR) to determine the relationship between trace element type and content and the CL properties of sphalerite. In general, sphalerite produces a spectrum of CL colour under electron bombardment that includes deep blue, turquoise, lime green, yellow-orange, orange-red and dull dark red depending on the type and concentration of trace quantities of activator ions. Sphalerite from most deposits shows a bright yellow-orange CL colour with lmax centred at 585 nm due to Mn2+ ion, and the intensity of CL is strongly dependent primarily on Fe2+ concentration. The blue emission band with lmax centred at 470 - 490 nm correlates with Ga and Ag at the Tsumeb, Horn Silver, Balmat and Kankoy mines. Colloform sphalerite from older well-known European lead-zinc deposits and late Cretaceous Kuroko-type VMS deposits of Turkey shows intense yellowish CL colour and their CL spectra are characterised by extremely broad emission bands ranging from 450 to 750 nm. These samples are characterised by low Mn (<10 ppm) and Ag (<1 ppm), and they are enriched in Tl (1 - 30 ppm) and Pb (80 - 1500 ppm). Strong green CL is produced by sphalerite from the Balmat-Edwards district. Amber, lime-green and red-orange sphalerite produced weak orange-red CL at room temperatures, with several emission bands centred at 490, 580, 630, 680, 745, with lmax at 630 nm being the strongest. These emission bands are well correlated with trace quantities of Sn, In, Cu and Mn activators. Sphalerite from the famous Ogdensburg and Franklin mines exhibited brilliant deep blue and orange CL colours and the blue CL may be related to Se. Cathodoluminescence behaviour of sphalerite serves to characterise ore types and help detect technologically important trace elements.

Jan 1, 2008

A three-dimensional finite element analysis is used to determine the stress intensity factors associated with the chevron-notched semi-circular bend test specimen. The stress intensity factor calibration is done over a range of crack lengths a

Jan 1, 1998

By Barns K. E, Munro P. D, Brindley S. K

Ernest Henry Mining Pty Ltd started production in August 1997. The Ernest Henry orebody consists of two distinct parts, a complex supergene ore zone overlying a primary ore zone. The economic copper minerals in the supergene ore are chalcocite

Jan 1, 1998

By Nag D. K

King Island Scheelite is a wholely owned subsidiary of Peko-Wallsend Ltd. The company works two underground mines near the southern end of King Island at the western approach to lass Strait, 240 km south of Melbourne. (See ^igure 1).

Jan 1, 1981

By S Arya, A Bhandari

Dust emissions by blasting are of concern to both mine operators and surrounding communities. The quantity of dust produced, and the effects of its dispersal depend substantially on geological, blasting and meteorological conditions. This paper provides details of methods used to quantify the amount of dust produced after collecting samples using high volume dust samplers, and the difficulties encountered in satisfactory dust sampling and quantification. Also described are practical dust reduction methods by using water filled ampoules and water filled balls.

Jan 1, 2004

By Misra A

The development of roadways in underground mines in Autralia is by conventional continuous miner technology. The rate of development achieved using this technology is improved by modifications to this technology using additional equipment such as surge cars or decreasing roof bolting time.Development rates achieved with this technology compare with developing technologies such as high capacity continuous miners, continuous transportation and simultaneous cutting and bolting systems such as the Kemcol Beaver. Pillar dimensions have an effect on the rate of development.'

Jan 1, 1991

Consolidated Rutile Limited's (CRL) operations incorporate the exploration, mining, processing, marketing and distribution of mineral sands. This paper outlines the current scope of CRL operations in vegetated sand dunes on North Stradbroke Island (NSI), Queensland. Included are some specific comments relating to design and construction of high capacity dredges which float in artificial ponds and are an integral part of mining high dune ore reserves. Three floating cutter suction dredges with combined sand throughput capacity in excess of 7000 tph are used in mining operations on NSI. Initial processing is by gravity and magnetic methods on large wet concentrators also floating in the artificial ponds. Spiral sluices are used exclusively in the newest concentrator, which has the highest recovery of heavy minerals.

Jan 1, 1986

Haematite Recovery from a Tailings Stream Laboratory and pilot scale testing were carried out in 1999 on a tailing sample from a North American iron ore plant using gravity, magnetic and flotation techniques. The ore contained 16 per cent iron mainly in the fine (-38 ¦m) size fraction. Two methods of evaluating the separation efficiency were used; Selectivity Index and Z factor analysis. Tabling and magnetic separation produced poor results, with flotation testing showing some promise, generating concentrates assaying more than 40 per cent Fe. High grade concentrates containing more than 67 per cent Fe were generated using the Kelsey Centrifugal Jig, and it was recommended that this technique be pursued at a larger scale to verify the results obtained.

Sep 13, 2010

Measurable physical characteristics of placer deposits include both fluvial sedimentological features and their related heavy mineral suite. These two important identifiable factors are interrelated and generally compliment each other furnishing a complete geological geochemical tool in cost- effective placer evaluation. Heavy mineral suite composition and character will change downstream from the provenance area and will compliment the related sedimento logical environment. Careful attention to gold particle characterization during the exploration phase will indicate new source additions, enhance deposit evaluation techniques and greatly assist in maximizing metallurgical efficiencies. Recognition of the various characteristics within these fluvial systems should enhance the total contained geochemical suite evaluation considering a finite source. Failure to recognize and measure these two important features very frequently leads to frustrated and unrewarding placer evaluation objectives.

Jan 1, 1986

By J Hadjigeorgiou

Underground mines often rely on ore pass systems to ensure the transport of ore and waste. Consequently, it is important to ensure the smooth operation of such systems. Ore pass degradation that may require rehabilitation results in production delays and high operational costs. The occurrence of hang-ups within an ore pass also leads to disruption of ore production. There are important safety concerns when worker intervention is necessary to re-establish material flow in the ore pass. In order to facilitate the design of ore pass systems, mining operations often rely on past experience, or semi empirical guidelines. This paper describes recent efforts to establish a comprehensive database on current practices; encountered operational problems and solutions in ore pass design in Quebec underground mines.

Jan 1, 2003

By Roberts JD

The design and installation of a major on-line stores and purchasing system, with built-in maintenance reporting and plant register capabilities, needs more than just close attention to computer design details. When the system must be available almost 24 hours a day to a number of mine stores sites, and is used by a variety of mining staff including engineers and stores clerks, as well as by remote purchasing and office staff, then simplicity of use, availability, fast response times, and other human factors become vital. Critical aspects include easy to use screen design, involving a change from the traditional hierarchical menu system, and fallback and recovery to the last transaction. Business, people and systems objectives need to be established at the preliminary design stage, so that results can be measured and corrective action taken. The amount and type of user involvement and training, at all stages from initial design to systems tuning, has a major effect on people wanting to use the system. Active user participation in systems design, data definition and collection, and use of relevant training material is needed. Project management and design problems can arise in working with database oriented computer staff, and certain design features are found useful in ensuring a responsive, robust overall system.

Jan 1, 1983

By A Moreira, A B. De Souza, S Latchireddi, E Faria

Material transport plays a significant role in the efficiency of horizontal grinding mills - autogenous (AG)/semi-autogenous (SAG)/ball mills. The magnitude of benefits that can be achieved with efficient material transport in AG/SAG mills has been demonstrated in a greenfield milling operation at Mirabela MineratpoÆs SantaRita Nickel operation located in north eastern Bahia in Brazil. This grinding circuit was commissioned in October 2009, was designed as a typical SABC circuit to grind 4.6 Mt/a (575 t/h) to produce a P80 of 125 ¦m with ten to 12 per cent ball charge in the SAG mill. However, it has been operating as an ABC circuit without any grinding media in SAG mill. The nameplate design capacity was achieved in few days and was gradually increased to an average of +800 t/h, still operating in ABC mode. The Santa Rita grinding circuit consists of one 30 ft + 15.4 ft 8.5 MW SAG mill fitted with Outotec patented Turbo Pulp Lifters (TPLÖ) in closed circuit with a HP400 short head pebble crusher and one 20 ft + 28.4 ft 5.5 MW Ball Mill in closed circuit with a Warman cyclone cluster fitted with 10 + 26 in CAVEX cyclones. This paper examines the comminution design process, operating philosophies, experiences, post commissioning optimisation and future development works. Evaluation of the milling circuit performance relative to the design criteria is also discussed.CITATION:De Souza, A B, Latchireddi, S, Moreira, A and Faria, E, 2012. Application of turbo pulp lifter in greenfield operation - Mirabela SantaRita nickel operation, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 53-58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012