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By H Thanasekaran, L Christodoulou, J Kohmuench

"Column flotation has been successfully applied to iron ore concentration since the 1980s with the goal of reducing silica content and allowing for the efficient production of pellet feed. Since then, columns have been widely used in iron ore processing due to: their lower capital and operational costs when compared to conventional cells their ability to generate higher concentrate grades and recoveries.Currently, more than 100 columns have been installed within Brazilian iron ore processing circuits for rougher, cleaner and scavenger duties. Despite it being a well-established approach, several technological advances have improved column design, accessories and performance. This work presents the performance of some iron ore columns in Brazil and the recent technological developments.CITATION:Thanasekaran, H, Kohmuench, J and Christodoulou, L, 2013. Column flotation of iron ore - status and advances, in Proceedings Iron Ore 2013, pp 479-484 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

Ledcap Pty Ltd has developed two software tools for assisting in the determination of life-of-mine (LOM) trucking requirements. The first tool generates haul paths and the second calculates truck travel time over these paths. The two step approach allows the paths to be viewed and if required edited, to better represent the actual site haul routes.The first tool automatically creates haul paths between the mine bench and the dump. To do this the user supplies a master haul route and a scheduled block model. The master haul path and the block model are interacted to create multiple haul routes, one for each pit/dump bench pair in each scheduling period. Each path carries with it a record of the scheduling period it represents and the dry tonnage hauled over the path in that period.The second tool calculates truck travel time over the path. Data from the manufacturer's rimpull and retarder curves are used to calculate accelerations and speed over each segment of the haul path. As the paths are derived from digitised representations of mine haul routes the path f les often have over a hundred segments. This detailed representation of the haul route allows the software to automatically adjust speed for different radius corners and accurately simulates the changing accelerations over the gradient changes that occur in real life mine ramps. Rolling resistance can be specified at a global level, at a segment level and at a period level. This allows rolling resistance to be changed seasonally as well as spatially.Life-of-mine trucking studies attempt to calculate an accurate answer from extremely variable inputs. This paper will detail the features of the two software tools and how the tools provided in the software can assist the mine planner to have greater confidence in their life-of-mine trucking requirements and the subsequent production capacity inputs to their scheduling calculations.

Dec 6, 2010

By Weber P, Sneyd S

The total world steel production in 1998 amounted to approximately 780 000 000 t. The share of electric steelmaking was in the range of 35 per cent and is expected to increase further to over 40 per cent of the world's production within the next ten years. As electric steelmaking is primarily based on the use of scrap and as it is progressing more and more into higher steel grades the need for low-residual metallics will become increasingly important. Consequently, the demand for scrap substitute material will increase, reflected in the world wide spate of interest for DRI (Direct Reduced Iron) and HBI (Hot Briquetted Iron). The increased significance of DRI/HBI as a substitute for steel scrap has obviously emanated also from its comparatively lower and more predictable costs per ton and definable chemistry. In 1998 already 37 million tons of DRI/HBI were globally produced.

Jan 1, 1999

The application of biogeochemical methods in mineral exploration in semi-arid to arid environments in Western Australia has been investigated in an area near Norseman.The study involved a comparison of trace element characteristics of rock, soil and plants in the vicinity of the Pioneer BB prospect, where nickel-iron sulphide mineralization occurs in a "greenstone" sequence of ultrabasic, basic and sedimentary rocks.Analyses of unweathered and partly weathered rock from diamond drill cores show the ultrabasic rock to be highly variable with respect to Ni, Cu, Co, Zn and Mn.Samples of weathered bedrock and overlying soil were analysed for total trace element contents and for the trace elements associated with secondary iron and manganese oxides. Approximately 30 per cent of the total nickel content of the weathered basic rock is associated with secondary iron and manganese oxides, compared with approximately 15 per cent in the weathered ultrabasic rock.The soil has a sufficient residual content to provide a reliable indication of the chemistry of the underlying rock. Total trace element analyses of the -89 mesh fraction show strong anomalies for nickel and copper over the mineralized zone. Important amounts of nickel, cobalt and, to a lesser extent, copper are apparently associated with secondary iron and manganese oxides in the soil.Melaleuca sheathiana (tea tree) has been used to study the relationship between soil and plant chemistry. No strong relationship between plant and rock type was observed. Analyses were made of leaves, twigs, wood, bark and roots, and all plant organs were found to have anomalous nickel and copper contents near the mineralized zone. Leaves were found to give the best contrast in the anomalous area and to show fewer erratic values than other organs. It is concluded that the uptake of trace elements by tea tree is low in the semi-arid to arid environment of Western Australia, but that analyses of the plants do reflect the presence of mineralization.

Jan 1, 1973

Eco-Efficient Gravity Separation Solutions in India Sustainable development and social responsibility issues are a principal aspect of mineral processing operations around the world. With the need for more environmentally effective technologies, some gravity separation systems have provided eco-efficient mineral processing solutions in places where it is not otherwise viable because of lack of fresh water or for other environmental reasons. Advanced spiral separation technologies developed in Australia offer a cost effective and environmentally viable way to process minerals. In particular, we review recent case studies of spiral plants commissioned in India where environmentally sustainable solutions to design problems included the use of spirals operated with sea water and the use of high capacity (HC) spirals to provide low consumption of energy and materials and a reduced plant footprint. This paper evaluates the performance of various spiral plants in India and how critical environmental issues which affect the overall viability of wet concentrating processes where resolved.

Sep 13, 2010

A President, soon after he is appointed, sees looming ahead of him the Presidential Address; and in something approaching despair wonders what he can possibly talk about which might hold the interest of his audience. After various casts about, it occurred to me that perhaps prospecting, and more particularly prospecting in Australia, might provide a subject. This is because, 'in the first place, 'prospecting is passing from the stage of chance surface discovery to that of systematic search applying scientific methods to theproblems involved, and in the second, it is the section of the industry with which I have been concerned through much of my: working life. As it makes an address of this sort more interesting if it includes specific reference to actual experience, I hope you will bear with me in such references to actual prospecting as I may use to illustrate the argument. Prospecting has always carried the glamour of sudden wealth. The picture of the prospector engaged, perhaps for years, in fruitless search suddenly coming on riches beyondhis hopes is, deeply etched in the Australian imagination. In few other places has the fervour of prospecting run higher than it did in Victoria in the generation beginning little more than a century ago following the discovery of gold.People arrived from overseas in great numbers. Most of them proceeded to: the goldfields. They moved in thousands from new find to new find. In 'so doing' they determined much of the course of the State's development. The experience of prospectors led them to formulate all sorts of theories little impeded by awkward facts, to account for the apparently unpredictable occurrence of gold.The ideas which men followed, occasionally to success, and which they were prepared to back with all they had were strange and, various, many stories are told of them.

Jan 1, 1959

By S McKinley

"The White Mountain sediment-hosted gold deposit is located in north-eastern China. Mineralisation is associated with silica–hematite–altered polymict breccias that occur within dolomite at or near the contact with overlying sandstone. Economic gold grades are controlled by the distribution of the polymict breccias and can transition rapidly to low or zero grade over short distances. This results in sharp and highly irregular ore contacts on whose accuracy proper stope design and ore control is reliant at this blasthole underground mine.Short-term planning and ore control utilise a grade control model created from infill drilling and grade control sampling (ie face and wall sampling). Typically, the grade control model was maintained by time-consuming manual editing of earlier made contacts to incorporate any new data. This approach also was quite error-prone due to: the complexity of the breccia and ore grade contacts irregularly oriented and/or insufficiently dense drill holes inconsistent incorporation of grade control sampling. These errors resulted in unplanned dilution and ore loss due to inaccurate interpretation of the ore contacts.The primary advantage to implicit geological models over conventional, manually-built wireframe models is that they can be updated very quickly and frequently. In a mine setting, the power and efficiency of using an implicit model is greatest where the use of manual inputs or editing can be minimised. Recently a workflow was set-up for the mine geology team to create an implicitly-modelled ore shape for short-term planning needs by using all data, especially all grade control samples. The resultant 3D shapes provided metre-scale accuracy and consistently reconciled complex ore geometries much faster and to a higher degree of quality relative to the wireframe model. The mine stakeholders can now obtain an accurate ore model that will always be in sync with available data.CITATION:McKinley, S, 2017. Application of implicit geological modelling to improve the grade control process at White Mountain gold mine, Jilin Province, China, in Proceedings Tenth International Mining Geology Conference 2017, pp 385–392 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 20, 2017

The paper presents a brief history of endeavours to start a mining education programme which began in the days when Papua New Guinea's first large mine, at Panguna (Bougainville), was coming into production. The status of the Public Investment Programme in Mining Engineering and the facilities being created for the education and training of Papua New Guinean citizens in mining and mineral processing are also described. Future expansion plans are also detailed including those for the commencement of petroleum engineering and geological engineering which would include courses in mining geology, exploration geology, engineering geology and petroleum geology. The paper also looks at the manpower training requirements in the lower levels of mining industry such as pit foreman, blasting foreman and other similar positions. It stresses the need to start mining technical training programs at pre- employment level and at certificate level in a technical college, possibly Lae Technical Colleqe.

Jan 1, 1991

By Wylie A. W, Mathew P. J, Eisler P. L

Field studies of the radiations backscattered by iron ores from a 60Co source of primary gamma radiation located in a borehole logging probe have confirmed thatthe P" factor, a ratio of high energy gamma ray intensities to low energy intensities in selected energy windows of the backscattered gamma-ray spectrum, is a valuable measure of grade for sedimentary iron ores of the Pilbararegion of Western Australia.Laboratory studies of model boreholes have shown that variations in borehole diameter and variations in bulk density of the formations have a significant influence on the measurement of P" ratios. If these influences 'are taken into account the mean ore grade in a new blast hole, for instance, can be predicted with a probe of suitable configuration to within 0·8 per cent Fe at the 95 per cent confidence level, while the grade of a single 120-cm split can be determined to within 2·6 per cent Fe. These results were obtained by pooling data from five blast holes covering the range of iron concentrations 20-68 per cent Fe and apply to the mean hole grades 54-68 per cent Fe.Results for two development holes were generally comparable to those obtained from individual blast holes95 per cent confidence limits of ±0·9 per cent Fe for mean ore grade and ± 4·1 per cent Fe for single splits. A greater number of data points is needed before these confidence limits can be further improved.The technique utilized to obtain these results was derived from a "multiband" approach to collection of backscattered spectral intensity data, an approach which permitted selection at the data processing stage of the most statistically significant P" ratios for the type of mineralization encountered in the field. The multiband technique also permitted selection of the most significant of another set of windows in the backscattered gammarayspectrum to measure a newly developed "S-factor", a ratio sensitive to borehole diameter. Another window provided information on bulk density. All these measurements were made with a single pass of the same loggingprobe.

Jan 1, 1977

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, minus what is taken up by the rivers and streams is suitable for settlement, and certainly two-thirds is good land. The gross area of the district is 2,417,299 acres. The principle rivers are the Wanganui, Mokau, Waitara, Patea and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").THE OIL-FIELDThe discription of an oil-field now-a-days usually resolves itself into a mass of figures and statistics, of great interest and value to the engineer and commercial man, but practically indigestible to the general public. It is the realm of the financierand the captain of industry.

Jan 1, 1912

A variety of environmental financial assurance instruments are in use across the globe. This paper reviews some of the more common forms currently used in New Zealand, Canada, USA and Australia. In order to be effective, the form of assurance instrument selected needs to be aligned with a countryÆs specific environmental objectives, geography and political climates and also allow for a healthy investment climate. Industry and Government both have a strong interest in ensuring financial assurance criteria meet these objectives.   Recently Golder Associates have been involved in financial assurance assessments for various mining and quarrying companies across the South Island. Multiple stakeholders and regulatory agencies can make the setting of effective and fair financial assurance criteria a complex exercise for both regulatory agencies and industry.  The author relates experience gained in assessing financial assurance under current New Zealand legislation (RMA, 1991), effectively dealing with issues such as ôdouble bondingö and overviews potential approaches to dealing with transitional issues for historic and existing operating mine sites.

Jan 1, 2006

Improvement of Phosphate Ore Flotation Performance Through Sized Flotation

Sep 13, 2010

By A Rozendaal

Namakwa Sands, a heavy minerals beneficiation business situated along the west coast of South Africa, is a major producer of titanium slag, pig iron, ceramics quality zircon and rutile concentrate to the international export market. The bulk of the economic mineralisation, which includes zircon, rutile, ilmenite and leucoxene is hosted by a late Cainozoic aeolian succession overlying remnant palaeo-strandline sediments. Relatively younger duricrust layers that cement a significant part of the generally unconsolidated ore compounds the challenging processing character of the primary mineralogy. The complex nature and hardness of the duricrust ore influence their mineability negatively, and can potentially destabilise downstream ore preparation processes. Effectively, up to ten per cent of the entire mineral resource is sterilised as the present infrastructure is not geared to treat the hard-mineralised ore. The metallurgical performance of the primary processing stage, which entails wet density separation, is strongly a function of the quality of the heavy mineral assemblage, liberation state of the economic minerals and slimes content. Elevated concentrations of garnet, a gangue contaminant exhibiting similar physical characteristics as the economic minerals, subtract substantially from the recovery performance of the secondary concentration process, which comprises mainly wet magnetic separation. By contrast, the intrinsic mineral purity of the economic fraction governs its successful recovery to saleable products as stringent product quality specifications apply. Improved mine planning through geometallurgical enhancement of the existing mineral resource model is envisaged to benefit the entire Namakwa SandsÆ mineral beneficiation chain, ultimately aiming to optimise mineral resource utilisation.

Jan 1, 2008

By P J. Minehan

The investigation of the potential of the Webb/Baynes block of the Buller coalfield for anode carbon manufacture has generated much information on the physical beneficiation characteristics of the Buller coals in general. A further 36 drill holes of the block in question and several other samples have been analysed by sink/float analysis, either at a single density or over a range of densities. In addition, many samples have been beneficiated on a laboratory shaking table or by flotation. The ash content can be reduced by a variable factor. The reduction factor of between two and four by sink/float analysts is understandably less for tabling where separation is not perfect. All Buller coals behave similarly, there being greater ash reduction factors for higher ash coals.

Jan 1, 1983

Within CRLÆs lifetime there have been a number of products that have proceeded through their life cycles. In each case market forces and technological advances have forced the cessation of the product. The company has then had to develop alternative outlets for its copper. Sometimes it has produced a similar product to fill the same market. In other cases the extra copper is sold as cathode. Today, CRL produces no semi-fabricated copper products and all cathode is sold. More recently, CRL has ventured into the sale of technology and manufacture of cathode motherplates. This area, whilst it is not what had been a traditional area of core business, has been found to be profitable.

Jan 1, 1998

Leading Article from "British Medical Journal," London, 4th, November, 1944.Assuming that silica exerts its injurious effect upon animal tissue through a slow transformation into silicic acid, Denny, Robson, and Irwin thought that if the solubility of siliceous material retained in the lungs could be suffciently reduced the usual fibrotic response could be diminished or prevented. They discovered that aluminum powder rendered siliceous material insoluble in vitro by coating the silica particle with a thin film of gelatinous hydrated alumina, which on drying formed crystalline alpha aluminum monohydrate. The presence of this adsorbed layer on the surface of the quartz was shown by staining it with aurin. That metallic aluminum dust produced no fibrosis in the lungs was demonstrated by dust-inhalation experiments on eight rabbits. Attempts were therefore made to prevent silicosis by mixing quartz with metallic aluminum dust.Animals exposed to quartz dust developed typical silicosis in about five months, but the addition of 1 per cent. aluminum powder prevented this even after exposure had been lengthened up to 22 months, provided the aluminum powder was of a particle size below 5. This year Crombie, Blaisdell and MacPherson have reported the treatment of 34 silicotic miners by the daily inhalation of fine aluminum powder freshly ground from small aluminum pellets in a specially constructed mill. Daily treatment began with five-minute inhalations, which were gradually increased to 30 minutes. Some of the men received 300 treatments, but the majority only 200. Out of the 34 cases thus treated clinical improvement was manifested by lessening or disappearance of shortness of breath, of cough, of pain in the chest, and of fatigue. In 15 cases the condition became stationary and remained so in spite of continuous employment in silica dust throughout the treatment. The progress of the disease was assessed by means of tests for respiratory function repeated at three-monthly intervals. Obviously this treatment cannot be regarded as a cure for silicosis, since it cannot restore lung tissue which has undergone fibrotic change; but Crombie and his colleagues believe that the inhalation of finely particulate aluminum powder offers every prospect of preventing the development of human silicosis.In view of these findings, it is surprising that repeated papers by Goralewski from Germany describe various types of lung disease attributed to aluminum dust, and press for them to be scheduled under the Workmen's Compensation Act in that country. Seven hundred workers were investigated. They were making, probably by a stamping process, aluminium powder containing about four milliards of particles of dust per grain, and are reported as complaining of dry cough with pain on breathing, shortness of breath, poor appetite, and gnawing abdominal pain. Spontaneous pneumothorax developed in four workers. No abnormal physical...

Jan 1, 1945

By A Giblett, R Dunne, D Appelhans

There are a number of hurdles that must be negotiated in order to design an effective gold ore treatment facility such that the expectations forming the basis of project economics are valid and can be achieved in practice. Selecting samples based on geometallurgical context, performing and interpreting testwork relevant to the selected process flowsheet are essential considerations towards achieving this aim. This paper discusses recent experiences in process development for free milling gold ores giving consideration to frequently encountered challenges of this nature.CITATION:Giblett, A, Appelhans, D and Dunne, R, 2013. Considerations for effective gold process development, in Proceedings MetPlant 2013 , pp 445-454 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

The West Coast region of the South Island is situated astride the Pacific û Australian plate boundary zone. The most significant component of this zone is the Alpine Fault. A variety of reconstructions of the pre-Alpine Fault plate tectonic configuration of the New Zealand continental area have been attempted over the past 25 years or so. Most of these have not been closely constrained by a regional compilation of field data related to the age and horizontal displacement history of the Alpine Fault. A model in which the Alpine Fault was initiated no earlier than the interval 18 - 16.5 Ma (B.P.) is proposed, a significantly younger age of inception than has been widely accepted as the onset of dextral displacement along the plate boundary through the South Island. A subsequent history of displacement is presented consistent with the West Coast basin stratigraphy. The alluvial gold content of some parts of the Miocene to Pleistocene conglomerate sequences is also discussed.

Jan 1, 1996

Mr Kapp's paper helps considerably to clarify the subsidence/mine geometry relationships in New South Wales. It is in the best tradition of the presentation of field investigations such as has built up internationalknowledge over the years.The Author has plotted in Fig. 10, the maximum subsidence developed over each of a number of panels of different width/depth ratios and concludes that the maximum possible subsidence over a super critical extractionarea is around 0.65 of the mining height and that this is reached with the critical width/depth ratio of extraction of around 1.5.Although, as Mr. Kapp says, the maximum possible subsidence in the UK can reach 90% of the seam thickness extracted the more usual figure for the first seam is up to 80%. It has also been found in the UK that with shallow workings such as those at Kemiro Coliery the critical width of extraction is 2.0 or more times the depth.

Jan 1, 1981

By D F. S Natusch, R J. Hooper

Recent lignite investigations indicate their potential as a strategic long-term fuel resource. This potential however would be determined not only by lignite quantity and quality, but also by economic, physical and social resources required to support it. The following discussion uses the example of a typical lignite mining operation to review the major resource requirements. While recognising that the implications of supplying those resources may be as important as their actual existence, this paper has purposely omitted such discussion as this will be one of the main target areas for the next phase of investigations.

Jan 1, 1983