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By L Spencer, H Zwingmann, I Graham, D Cendon, B Kelly, D Burkett, F Lau, P Lennox

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Kulumadau deposit represents an intermediate-sulfidation epithermal gold deposit (3.8 Mt at 2.3 g/t, Ag:Au = 1). Mineralisation is primarily confined to hydrothermal breccias within pre-existing fault zones, where it is disseminated throughout a hydrothermal matrix comprising chlorite-quartz-adularia-illite-I/S clays-calcite-pyrite. The host sequence represents numerous mid-Miocene pyroclastic flow eruptions within a tectonically active emergent shallow marine to subaerial depositional setting. Subsequent growth faulting was responsible for debris avalanches, which were subsequently cut by reverse faults. Faults were exploited by hydrothermal fluids, with the heightened porosity at the juncture between faults and debris material facilitating boiling of the ore constituents. Fluid inclusion studies suggest that fluid mixing between meteoric fluids and magmatic fluids, accompanied by boiling, were the primary mechanisms for gold deposition. The occurrence of anhydrite/gypsum as late-stage veins and their sulfur and oxygen isotopic values indicate post-mineralisation mixing of sea water with hydrothermal fluids.CITATION:Burkett, D, Graham, I, Spencer, L, Lennox, P, Cohen, D, Zwingmann, H, Lau, F, Kelly, B and Cendon, D, 2015. The Kulumadau epithermal breccia-hosted gold deposit, Woodlark Island, Papua New Guinea, in Proceedings PACRIM 2015 Congress, pp 205–212 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

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

The interaction of flotation collectors with sulfide minerals takes place at the solid - solution interface. The electrochemistry of the processes which affect this interface are discussed. The interaction of xanthates with sulfides is an electrochemical process, xanthates being electro-oxidised to chemisorbed xanthate and dixanthogen. The role of oxygen is to provide a cathodic process to allow the anodic oxidation to occur. The hydrophobic condition of the mineral surface is brought about by the presence of the oxidised xanthate species. The action of reagents which can activate or depress the flotation of sulfides is discussed briefly.

Jan 1, 1971

By using knowledge-based technology to create a Virtual Mining Enterprise and integrating it with existing technical and financial computer systems, a gold mining company has been able to reduce the time taken to produce a mine plan from 14 weeks to less than one week. Typically, the mine planning process requires circulating and managing large amounts of information. Even with the use of computers in todayÆs business, this is often still a manual process involving file transfers and individualised spreadsheets. Mine planning also involves understanding and managing large quantities of complex and interrelated variables. Added to this is the ever changing dynamics and constraints associated with the business of mining. These issues not only hamper the planning process but also question the validity and usefulness of the mine plans being generated. By integrating the information and knowledge of the numerous departments involved in mine planning into one core Knowledge Base - so called æone version of the truthÆ, - mining companies are able to overcome these pitfalls experienced in traditional planning methods. Once set up, the Knowledge Base creates and runs a virtual mining enterprise with which to visualise and test various scenarios of mining, business and logistical activities. The final output is an optimised enterprise-wide plan with clear and detailed instructions for each of the divisions of the company.

Jan 1, 2000

By A J. Falconer

Two magnetic parameters are proposed as a basis for the assessment of ironsands beneficiation. The parameters are determined for raw sand prior to dredging and for magnetic separator head feed over a production period of five months. The relationships between these parameters and the performance of the magnetic separators are examined to establish the value of magnetic assessment compared with the traditional soluble iron assay method. The results illustrate that the first parameter, true magnetic fraction (TMF). Has a value superior to that of soluble iron when relating raw sand grade calculated by triangulation to magnet performance. In terms of the relationship between magnet head feed grade and magnet performance, TMF and soluble iron perform equally as assessment parameters. For the ironsands mined during the five month period, the second magnetic assessment parameter, composite fraction (CF), is shown to merely reflect TMF and offers no additional information for assessment. Conclusions are that true magnetic fraction has many advantages over soluble iron in terms of time and cost of determination and that it is a meaningful and reliable parameter upon which to base all calculations relating to the mining and beneficiation of ironsands.

Jan 1, 1980

The Barmac autogenous crushing mill is one of the most successful new comminution technologies to become available to the mining and industrial minerals industries in this decade.   The Barmac autogenous crushing mill is an innovative Vertical Shaft Impactor which operates in essence like a high intensity dry ore centrifugal pump with the reduction occurring primarily as a result of high velocity rock to rock impact in a fully rock lined crushing chamber.   With applications in a wide range of mining and industrial minerals operations the Barmac autogenous crushing mill presents an opportunity to enhance reduction and liberation whilst providing many cost savings and production increases in new and existing plants.   This paper briefly describes the operation of the Barmac autogenous crushing mill and reviews its benefits.

Jan 1, 1990

Ground conditions at the Kencana mine, Indonesia, are generally poor and an underhand cut and fill mining method is used for extraction. Due to these poor ground conditions, all vertical development has been conducted using blind, top-down, sink and line excavation methods. Due to time constraints, raiseboring was considered the only viable excavation method for the installation of a return ventilation system for the K2 (Kencana extension) project. In order to achieve successful raiseboring in the poor ground conditions a number of strategies were used including: a detailed geotechnical study for optimal position of the shaft/s, splitting shaft excavation vertically, raiseboring of multiple smaller diameter shafts, extensive pregrouting, installation of drainage holes, and rapid installation of support following excavation.

Nov 25, 2010

Some low grade South Australian iron ores were classified on the basis of their physical characteristics. Ores from Mount Christie and Billeroo are coarse grained mixed ores; Mount Christie ore could be concentrated by gravity or dry magnetic separation at 10 mesh, but Billeroo ore needed to be crushed minus 36 mesh. Ores from Razorback Ridge and Wilgena Hill are fine grained mixed ores; ore from Wilgena Hill could be concentrated by flotation, but poor results were obtained on Razorback Ridge ore. Malcolm Creek ore is non-magnetic and crystalline, and can be concentrated by flotation, but the deposit is small. Ores from Grants Quarries and Peeralilla Hill are nonmagnetic and earthy and could not be satisfactorily concentrated.INTRODUCTIONThe Geological Survey of South Australia has for several years been undertaking a systematic study of the iron ore resources of the State (excluding the Middleback Ranges) in relation to their geology, reserves, and beneficiation. As part of the latter phase of the investigation samples of the ores have been submitted to The Australian Mineral Development Laboratories (AMDL), and it was the study of these samples which provided the material for this paper.The mineragraphic and metallurgical work was undertaken by several officers of AMDL and the results are contained in unpublished reports submitted to the South Australian Department of Mines. Field data published here was obtained from unpublished reports by G. F. Whitten, Senior Geologist, Iron Exploration, of the Geological Survey of South Australia.

Jan 1, 1964

By P F. Lauricella, D Hendri

In the Mesel sediment-hosted disseminated gold deposit, the spatial distribution of hydrothermal alteration is controlled by steeply dipping faults and shallowly dipping lithologies. Hydrothermal alteration of carbonate rock is characterised by decalcification, dolomitisation and silicification. Intense argillic alteration occurs in a laccolithic andesite intrusion adjacent to decalcified and silicified carbonate units. Sulphide minerals (pyrite, realgar, orpiment, stibnite and cinnabar) accompany hydrothermal alteration and precious metal mineralisation. The trace elements Ag, As, Sb and Hg are zoned spatially throughout the deposit. Mesel contains a mineable gold reserve of 7.8 million tonnes at 7.3 g/t Au. Gold mineralisation is preferentially localised in carbonate rocks adjacent to and beneath the andesite intrusion. The ore body consists of a central, near-vertical, high grade 'feeder' system flanked by tabular, inward dipping, moderate grade 'ouflow' zones. Mineralisation is controlled predominantly by two steeply dipping faults with high grade (=10 g/t) gold zones centred about structural intersections and fault splays. Gold is submicron size and locked in very fine grained (<10 microns), disseminated and fracture-controlled arsenical pyrite. The Mesel deposit developed where high angle faults guided ascending, sulphidising fluids into reactive carbonate stratigraphy adjacent to and beneath the andesite intrusion and during subsequent migration of the auriferous fluids along 'outflow' channels. Early decalcification and dolomitisation enhanced porosity and permeability prior to silicification and sulphidation. Gold deposition occurred late in the genesis of the deposit.

Jan 1, 1995

Treatment of the Siirt-Madenk÷y Ores by Flotation

Sep 13, 2010

Engineering education has become a matter of national concern, at last, so I would like to talk about the links between the mining industry, the universities and technological developments. The Australasian mining industry and the mining schools have collaborated closely since the first school was established in 1871 and during those years there were a series of remarkable technological developments. For example:In the late 1880s George AndersoIl Richard developed chloride leaching of gold at Mt Morgan. This made a large difference to the wealth of Mt Morgan Mining Ltd.In the mid 1890s Robert Sticht demonstrated that pyrite smelting was an economically feasible process at Mt Lyell and the wealth which came to Mt Lyell Mining Co from his outstanding work made it one of the great companies in the country.During the first 15 years of this century flotation was developed at Broken Hill and it has proved to be one of the great technological inventions of this century.In the 1920s G K Williams started his outstanding work on lead smelting and refining at Port Pirie, this was work which ultimately re-wrote the text book on lead metallurgy and established Port Pirie as the mecca for lead metallurgists.In the 1920s also Frank Stillwell, later joined by Austin Edwards, established the new science of mineragraphy at the University of Melbourne. They were both great geologists, both were superb scientists and oddly enough both were outstanding athletes.In the 1930s Dr Ian Wark, a man in the front rank of Australian scientists of any period, started his outstanding work on flotation, work which resulted in a text book which remains a leader in its field today.In the 1930s also Arnold Black at Broken Hill South Ltd picked up the work which had been done at Mt Lyell many years previously and eventually wrote the papers on hydraulic fill which demonstrated that he led the world in fill technology. What a remarkable story of achievement it was, it laid the groundwork for the great industry we have today. It was possible because the industry was well supported by outstanding university schools and I would like to talk about some of these.

Jan 1, 1989

By P R. Denize, V S. Wein

A brief review of the Waipipi Iron Sands Limited company history and operations over the past ten years is made along with a summary of the benefits of this mining company to New Zealand. Land rehabilitation procedures in coastal dune lands are described in detail and brief mention is made of a study of animal health and copper uptake. The paper concludes with a summary of the increased emphasis on agronomy and restoration as the mining operation commences dredging in a better class of grazing land.

Jan 1, 1981

By S Lush, R Polglase

McConnell Dowell is pleased to be given the opportunity to present two papers to this conference. The first is a general discussion paper on our work in the field of slurry transportation. The second will be a technical paper on the development of a welded coupling compatible with urethane lined pipework. We trust that by discussing our recent work we can leave two lasting impressions on you: the versatility and useful role of slurry transportation, and the leading role taken by New Zealand in this technology This paper discusses three recent projects the New Zealand Steel Ironsand Transfer Line the Coarse Coal Ship Loading Technology the Nerang River Sand By-pass System. These have followed on from the other slurry projects with which McConnell Dowell has been associated such as the ironsand export trade at Waipipi and Taharoa. The New Zealand Contractors Federation awarded the Construction Award for 1986 to McConnell Dowell for the Ironsand Slurry Pipeline.

Jan 1, 1986

By J J. J Chen, J C. Zhao

A water/air model was developed to simulate the refining of molten aluminium by the sparging of gas through an impeller. The optimal gas dispersion depends upon selecting the correct gas rate for a given impeller rotational velocity to prevent flooding or channelling. Correlations illustrating this flooding behaviour exist for standard impellers within standard tank geometries. However the validity of these correlations has not been substantiated for gas dispersion in high temperature molten metals with non-standard tank and impeller dimensions. Metal refining is most efficient when fine bubbles are generated and uniformly distributed within the treatment tank. The application of some measuring technique able to detect this distribution within a non transparent operating treatment tank would be invaluable, enabling the optimisation of gas flow and impeller speed.   A technique has been developed to measure the pressure fluctuation levels at specific points in the water model. Comparison of these pressure fluctuation data with photographic evidence obtained in the water model suggests that the flow regime in the metal treatment unit may be determined using this technique.

Jan 1, 1995

By Munro P. D

Eh-pH measurements were taken on an industrial zinc reverse flotation process at Brunswick Mining and Smelting Corporation Limited. Laboratory zinc reverse flotation testwork on samples of the feed to the industrial process produced Eh-pH data which were similar to the data from the industrial process.Later, the Eh-pH data from the industrial process were compared with data from a pilot plant scale zinc reverse flotation process at Mount Isa Mines Limited. After comparison with the data from Brunswick Mining and Smelting Corporation, deficiencies in the pilot plant Eh-pH data could be recognised and corrective actions were taken for the pilot plant. A robust pilot plant zinc reverse flotation process was obtained with consistent performance at the expected level.The implications of these findings for a range of processes are also discussed.

Jan 1, 1988

By S M. Loewen, J J. Fuykschot

Located in the north-west of Kazakhstan is a world-class podiform chromite deposit. Donskoy mining and beneficiation complex (DGOK), a branch of Kazchrome TNC, which is a subsidiary of the Eurasian Resources Group (ERG) operates two underground mines in this area, one of which is the ‘10th Anniversary of Kazakhstan Independence’ (DNK) mine.The mine currently applies the gravity caving mining method, producing 1.8 Mt/a of ore utilising a slusher layout and rail transport to the hoisting shafts. The deeper zones form the largest mineral resources at the DNK mine and are planned to be developed in the next several years. At this depth, the generally poor ground conditions, combined with the high in situ stress state will potentially lead to extremely challenging mining conditions.This paper describes a technical study undertaken by SRK to determine the possibility of increasing the maximum production rate from the currently envisaged 6.0 Mt/a to 7.2 Mt/a, and to reduce the time taken to steady state production.Based on a newly created 3D model, the inclined caving method was proposed for the largest orebodies. This method, presently not implemented at any operating mine, although planned for two other projects, was deemed very suitable to deal with the weak rock mass characteristics and the plunging morphology of the mineralisation.Dassault Systèmes’ GEOVIA’s Footprint Finder software (a module of GEOVIA’s PCBC™) was used to determine the caving zones and production schedules. The total mine design was completed in Deswik software, and resulting schedules combined in Excel.In addition to the use of an inclined caving method, several other suggestions were made to increase the productivity of the mine, such as the application of a conveyor belt system transporting multiple material types, teleremote technologies and the application of thin sprayed liners to reduce the swelling of the rock mass.CITATION:Fuykschot, J J and Loewen, S M, 2016. Inclined caving option for the DNK mine, Kazakhstan, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 669–682 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By L Hussey, H Thanasekaran, J Kohmuench

Conventional flotation technology has historically failed to achieve high recoveries when treating <15 µm particles (Lynch et al, 1981). The new StackCell™ flotation technology was developed to specifically target this particle size range, and was tested at pilot plant scale at Mt Keith Nickel Concentrator. The streams tested, Slimes Rougher Tailings and Fines/Slimes Cleaner Tailings, represent 21% and 11% of the total nickel lost to tailings in the plant. Laboratory scale test work indicated that an economically significant fraction of these losses was consistently available to be recovered by additional flotation. The pilot plant experimental scope included over 50 tests. A grade recovery curve for each stream was developed, as well as information on the effect of ore type, feed rate, wash water, air flow, collector and frother on the performance of the cell. The single StackCell was able to achieve nickel recoveries of 16.8% and 16.5% on the Rougher Tailings and Cleaner Tailings, respectively, at grades consistent with these blocks. Additional test work of the StackCell in a cleaner scalper duty yielded final quality concentrate with a maximum nickel recovery of 59.5% for the single stage StackCell. Laboratory scale simulation of the downstream impacts of the StackCell operating as a cleaner scalper indicated a net recovery benefit of up to 2.0% for this cleaner block.Tests were completed to compare residence time requirements of the StackCell, as compared to conventional flotation. In 55 seconds, the pilot plant StackCell achieved 50% of the recovery of a 960 second laboratory scale conventional flotation on the same feed material. The apparent improvement in flotation kinetics is attributed to the novel high intensity aeration system, which provides efficient bubble-particle contact thereby shortening the residence time required to achieve high recoveries. The smaller footprint and lower energy costs of such a cell are also benefits of this technology, which is being considered for industrial scale installation as a result of this test work. Given the industry’s historical poor performance treating slimes with conventional flotation, it is clearly best practice to challenge the status quo through innovative new technology, such as the StackCell.CITATION:Hussey, L, Thanasekaran, H and Kohmuench, J, 2017. The application of high intensity flotation technology at Mt Keith nickel concentrator, in Proceedings MetPlant 2017, pp 259–278 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

Deposits of the Reefton Goldfield, West Coast, New Zealand, are hosted on N-NE striking, upright folds of the Greenland Group. High-grade quartz lodes are hosted on axial planar shears, typically have short strike lengths, and form shoots that pitch steeply on the hosting shears. Deposits within the field area of a detailed structural study share these characteristics. Field mapping and microstructural analysis have demonstrated that the Greenland Group was affected by a multideformational sequence. Gold mineralisation is hosted on shears axial planar to the F2 folds, but occurred during a subsequent deformation event (D4). Deformation during D4 resulted from N-NE directed shortening, near parallel to the trend of the F2 folds. This event produced F4 kink folds that were accommodated by layer parallel slip on S2 parallel shears, gold mineralisation during D4 being confined to the dilational hinges of F4 kink folds. The semi-brittle nature of D4 allowed the formation of stockwork veining and disseminated mineralisation within the F4 hinge zones. Most deposits within the goldfield are similar to those within the field area, and are interpreted to have been mineralised during D4. The two largest known deposits within the goldfield, however, are distinct. The Blackwater Deposit, striking parallel to the hosting folds, has a combined strike length of 1 km. The Globe-Progress Deposit is hosted on an E-W striking discordant shear in which a brittle zone of disseminated mineralisation encompasses high-grade quartz lodes. The characteristics that distiguish the Globe and Blackwater deposits may be due to formation before and after D4 respectively. Detailed field mapping in the vicinity of known deposits throughout the goldfield will further refine the relationships between the F2 folds, later deformations and the localisation of ore deposits. Additional mapping may also help constrain the position, orientation and extent of additional orebodies.

Jan 1, 2001

By P M. Ashley, M Muller

Massive sulphide ZnPbCuAg deposits in the Halls Peak district of north-eastern NSW are of the submarine volcanogenic type. They occur as a number of small lenses enclosed in shale and epiclastic rocks, in association with felsic volcanics of early Permian age. The deposits crop out in steep terrain near the eastern edge of the New England plateau. Local relief of 700 m and slopes up to 50¦, coupled with an average annual rainfall of about 1000 mm has led to local severe land sliding in previously mined areas. Mining from the 1890s to the 1960s has also resulted in unconstrained drainage of heavy metal-bearing acid waters and physical dispersion of finer grained metalliferous sediments into the Chandler River. Waters emanating from the main landslide area, from underground workings and draining scattered unconfined stockpiles of massive sulphide ore have pH values of 3 to 4 and contain elevated contents of Zn, Cu, Pb, Cd and Fe. Chemical mobility of heavy metals into streams occurs under low pH conditions with Zn exhibiting the greatest dispersion. Increasing pH conditions downstream cause precipitation of Fe phases and coprecipitation of heavy metals. Physical dispersion of secondary metal-bearing minerals into the surrounding creeks results in wt% levels of Cu, Pb and Zn in the stream sediments thereby exceeding the regional background values by one to three orders of magnitude. Areas disturbed by mining are characterised by lack of vegetation, biomagnification of heavy metals into algae and lower plants, and partial recolonisation by metal-tolerant grass species (Snow Grass, Poa sieberana; Blady Grass, Lomandra longifolia). Rehabilitation measures will have to include landslide stabilisation, impervious sealing or removal of sulphidic materials, import of topsoil and revegetation by metal-tolerant, slow-growing native grass and shrub species.

Jan 1, 1995

By R J. Holmes

The procedures and equipment used for sampling iron ore process streams have generally improved in recent years. However, there are a number of areas where significant issues still commonly occur, including sampling high capacity streams, sample cutter design and operation, division of primary increments at the secondary sampling stage, the performance of crushers installed to reduce the particle size prior to sample division, and the sample mass that is retained at each sampling stage. These issues of non-conformance with correct sampling principles are caused by factors such as increasing the speed and loading of conveyor belts to increase throughput, which changes the trajectory of the ore stream and may result in an inability of the sample cutter to handle the increased flow rate without sample loss. Failure to sample the entire primary increment stream at the secondary sampling stage is also a common issue as well as failure of crushers to provide crushed products of the required particle size due to ongoing maintenance and/or adjustment issues. These common pitfalls can all be addressed through careful attention to detail.CITATION:Holmes, R J, 2017. Common pitfalls in sampling iron ore, in Proceedings Eighth World Conference on Sampling and Blending , pp 261–264 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017