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Methods for Improving the Flotation Recovery of the Coarse Fraction of a Nickel Ore

Sep 13, 2010

By P M. Outhwaite

Everyone present today is especially aware of the need for minerals in this society of ours. The words 'especially aware' were deliberately chosen because this is a meeting of the NZ Branch of The Australasian Institute of Mining and Metallurgy not a dilettante group such as some of our critics. Members of the Australasian Institute of Mining and Metallurgy knew that our great farming industry, our shelter, our transport and our energy supply, are largely dependent on a flow of minerals into this country despite the presence of large coal and natural gas reserves. Flow in was said because New Zealand imports most of its mineral requirements with all the consequential strategic and economic disadvantages. If the above statements are accepted by this gathering it would be a premise fairly stated that New Zealand has a great need to discover and develop minerals.

Jan 1, 1976

By S J. Loach

Geological reconciliation is an indispensable part of BHP Billiton’s Western Australian Iron Ore (WAIO) operations. Since 2009 our reconciliations have been calculated in a single, centralised sequel-server database. This system draws data from across our operations and calculates a hierarchical sequence of reconciliation factors that span the company from the smallest grade control (GC) block to the whole of WAIO. It then presents the results using sophisticated graphical reporting tools.The initial motive for developing WAIO’s reconciliation system was to meet corporate compliance and public reporting requirements. The ability to validate our resource and reserve models by comparing their estimates of tonnes and grade with production figures remains the system’s principal function; however, as the system has matured, we have significantly developed its ability to support the improvement of various technical activities within the business. For example, the system can now calculate and report reconciliation factors for different resource classifications, short-term planning models and geometallurgical estimates.More recently, great emphasis has fallen on the system’s ability to detect and warn of possible geological issues that may pose a risk to either production schedules or product quality. We envisage a future where automated analysis of our large historical data set will enable high-risk conditions within future mine plans to be detected and highlighted.In all of these ways geological reconciliation plays an important role in contributing to this company’s financial and operational resilience.CITATION:Loach, S J, 2017. The development and future of BHP Billiton’s Western Australian iron ore geological reconciliation system, in Proceedings Iron Ore 2017, pp 415–422 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By G Bubner, C Gaughan

Magnetite mineralisation within the South Middleback Range has been known since the early 1930s; however, it was not until 1989 that BHP (then owners of the Middleback Ranges mining leases) drilled 10 700 m of diamond core into what was then known as the Iron Duchess low-grade deposit. In 2002 a review of Iron Resources left in the Middleback Ranges and the identification of downstream processing benefits using magnetite as a primary feed source led to the commencement of an 18 000 m resource drilling program of the high-grade core of the Iron Duchess low-grade orebody (renamed the Iron Magnet deposit). This paper describes the geology, processes and procedures used since drilling recommenced in early 2003. The Iron Magnet deposit is located 53 km southwest of Whyalla in the South Middleback Range, South Australia. It is a Paleoproterozoic stratabound magnetite deposit that lies down-dip and lateral to the Iron Duke hematite deposit, hosted within the Lower Middleback Iron Formation of the Hutchison Group meta-sediments within the Cleve subdomain of the Gawler Craton. Magnetite bearing host units within the Lower Middleback Iron Formation can be divided into a æmixedÆ basal sequence, a lower iron carbonate unit, a middle iron talc unit and an upper iron silica unit, all units grading up sequence and laterally into one another. The magnetite mineralisation is hydrothermal in origin. The strongest consistent mineralisation coincides with the iron carbonate unit, and the hematite orebodies of the Iron Duke are interpreted to represent up-dip supergene enrichment of the same unit. The Iron Magnet occurs within a large-scale parasitic syncline-anticline pair on the west limb of a larger syncline. Major bounding north-south shear zones occur on the east and west sides of the deposit. Cross-cutting west-northwest, northwest, northeast and east-northeast trending faults displace mineralisation. The commencement of drilling in 2003 lead to the migration of geological and geochemical databases, re-logging and re-assaying of all old cores that intersected the deposit, updating of logging codes and procedures, and strict Qa/Qc procedures to ensure the study satisfied JORC standards. External consultants were used for auditing and bench marking. The strong geophysical responses of magnetite and the wealth of close spaced ground magnetic and gravity data already completed over the Middleback Ranges allowed for refining of drill hole targets for the drilling program. It also provided an indirect method for ascertaining magnetite grade and tonnage volumes.

Jan 1, 2005

By D J. Woodward, A B. Christie, S A. Henrys

Low-level aeromagnetic data available in digital form have been combined to produce a new 1:100 000 scale map of total force anomalies of the Coromandel region, New Zealand. The map incorporates data from 13 surveys flown between 1977 and 1990 and shows the regional magnetic pattern as well as more detailed localised anomalies. In addition to magnetic anomalies, the map also depicts data to aid interpretation, including small-scale maps of topography, geology, magnetic intensity gradient and apparent magnetisation. The primary magnetic anomalies of the Coromandel region are associated with Late Miocene and Pliocene volcanic rocks, but have been locally modified by intense hydrothermal alteration caused by geothermal activity. Epithermal gold-silver and porphyry copper deposits are associated with zones of hydrothermal alteration. The map of magnetic anomalies can be used as an aid to mineral exploration and the interpretation of the processes that control the distribution of mineral deposits in the region.

Jan 1, 2001

Mining companies in order to compete and succeed in being viable business propositions must look to the future and select mining methods which guarantee improved efficiency and productivity as well as lower costs. A mining company in adopting a method of mining must now select the equipment most compatible. To some mines compatible equipment may mean the use of drilling jumbos to replace hand held rock drills or the use of load haul dump units to replace scrapers. To other more mechanised mines compatible equipment may mean the use of raise borers and road heading machines. The right decision will be where equipment compliments method in such a way that the working environment is improved, productivity is maximised, cost if reduced and all profit opportunities are optimised. An example of such is where the use of improved mining techniques in underground operations may see cut off grades reduced. By selectively mining these lower grade orebodies, smaller operation's ore reserves improve and the capacity for continued growth is enhanced.

Jan 1, 1990

By S M Richardson, A W McNeill, J B. Gemmell

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Hellyer, Fossey, Que River and Mount Charter volcanic-hosted massive sulfide (VHMS) deposits occur within the Que-Hellyer volcanics of the Mount Read volcanics, Tasmania. These deposits occur along a 6 km strike length and are hosted by the same stratigraphic unit. We use a combination of whole-rock geochemistry, short wavelength infrared (SWIR) spectrometry, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses and compiled historic whole-rock geochemical data to develop district-scale vectors towards VHMS mineralisation.Strongly sericite and K-feldspar altered rocks concentrate along a linear trend from Hellyer, through Que River, to Mount Charter. Ishikawa alteration index values and whole-rock major and trace element concentrations provide exploration vectors towards mineralisation on a regional scale as significant enrichment and depletion trends. On a deposit scale, composition variations in white mica (sericite alteration), chlorite and K-feldspar are observed and reflected in whole-rock geochemical variations. Regional SWIR data from drill core support the prevalence of phengitic mica and high-Mg chlorite within footwall alteration halos and highlight the main upflow zones of hydrothermal fluids in the VHMS district. The combined use of regional whole-rock geochemistry, SWIR and mineral chemistry is an effective way to highlight prospective areas for VHMS mineralisation in a mature exploration province.CITATION:Wu, S, Gemmell, J B, McNeill, A W and Richardson, S M, 2015. Exploration implications from variations in whole-rock and mineral chemistry around the volcanic-hosted massive sulfide deposits of the Que-Hellyer volcanics, Tasmania, Australia , in Proceedings PACRIM 2015 Congress, pp 85–90 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Prefeasibility planning and cost estimation of conveyor systems has historically been undertaken by comparing fixed plant transport requirements to that of similar systems in service. This paper describes the development of a prefeasibility conveyor technical design and cost estimation application using Microsoft Excel Visual Basic for Applications (VBA) platform. The application tool known as D-Convey (Dachshund Convey) was developed with the goal enabling the end user:- to develop a technical model for conceptualised conveyor systems,- to perform economic analysis on the developed technical model, and - to conduct a comparative and risk analysis.An Excel VBA based platform was utilised to draw upon both the analytical and graphical capabilities of a spreadsheet. Some of the features of D-Convey system include a revolutionary dynamic graphical help system, known as the 'information pane' in lieu of traditional help files as well as the use of familiar graphical user interface elements such as the MS Office 2007 task ribbon. The D-Convey system incorporates material database allowing for mass handling prefeasibility estimation in other industries; it has been validated at a local quarry.

Dec 6, 2010

By Moresby J. F

Segregation roasting was used to recover more than 85 per cent of copper from crushed, minus 14 mesh refractory furnace-lining bricks. A plus 14 mesh fraction: which was high in copper, could be recycled directly to the smelter, giving an overall recovery of approximately 90 per cent. An oxidation roast at about 700°C was necessary, before segregation roasting, to convert copper sulphides and copper metal to sulphates and oxides. Withsegregatron temperatures in the range 600°-650°C the quantities of solid carbon and NaCI required are 2-5 per cent and 1 per cent respectively. P.V.C. coating from scrap copper wire can be used instead of NaCl as asource of hydrogen chloride for the segregation reaction.

Jan 1, 1978

Conservation and environmental issues are raising their profile with respect to both demand restraint and electricity supply options. In New Zealand, conservation pressures and energy efficiency need to be seen in relation to the supply system currently in place which has capacity for economic supply of electricity in quantities substantially in excess of the current market. Consequently, energy efficiency and conservation need to be interpreted in relation to the supply system as well as in relation to end use. The relationship between the environment and conservation is strongest when new generation is required. New Zealand's electricity supply system consists of a large proportion of hydro production and this has significant environmental benefits when considered in relation to concerns of global wanning and the greenhouse effect. However, environmental trade-offs in supply options need to take account of both the efficiency of electricity end use, the trade-off between hydro and thermal generation and the inter-regional effects of shifting development options from one region to another. The Electricity Corporation has a high level of consciousness with respect to environmental and conservation issues and this paper demonstrates its own moves to maximise energy efficiency and illustrate the environmental trade-offs for supply.

Jan 1, 1990

The 8 ft by 91/2 ft drive which joined No. 7 Shaft with Browne Shaft on the 1,480 ft level was extended from both ends and met at a point approximately 12,000 ft from No. 7 (2,000 ft from Browne).The surveying required for this 2 1/2 mile haulage drive called for greater accuracy than was obtainable from South Mine standard methods. Procedures and devices from published information were tried and modified as required to suit local conditions. Several new methods were applied and improved as the drive advanced. The control of angular, linear and level measurements was perhaps considerably in excess of the requirements, but this was offset by abnormally large discrepancies resulting from shaft plumbing. The accuracy of the final breakthrough, although not to the standard desired, was sufficient to complete the connection without inconvenience and added cost.INTRODUCTIONThe acquisition of the Browne Shaft leases in January 1962 presented the management of Broken Hill South Limited with the problem of transporting ore from these leases to its mill. It was eventually decided that diesel locomotivehaulage through a 2t mile drive on the 1,480 ft level between the two mines was the best solution. The drive was advanced from both ends after Browne Shaft was deepened by 80 ft to reach the 1,480 ft level horizon. Each end advancedabout 15 ft/day with the miners working three 7 hr shifts. Blasting was restricted to the end of the shift.The survey work involved five shaft plumbings and 78 theodolite stations in a traverse, underground and surface,of more than 5 miles. Because of the exceptional length of the drive, an unusually high degree of reliability was required.The aim was for a maximum error at breakthrough of 1 ft 1 in 30,000, and to secure this, precise methods of linear measurement were necessary. Shaft plumbing in particular posed special difficulties.

Jan 1, 1965

By M Fallon

The full history of exploration successes, failures and related costs from initial greenfield exploration in 1987 to the current brownfield stages was analysed for the Plutonic Marymia Gold Belt of Western Australia. This belt, which had escaped the attention of turn-of-the-century prospectors and had not produced any gold until 1990, is an ideal area for a collectively exhaustive, progressive value and risk case study of expected return on gold exploration. The study analyses the progressive screening of over 200 greenfield and near mine prospects, through various stages of exploration to the establishment of 38 mining sites, ranging from a few large mines to small satellite operations. It provides empirical estimates of the historical Bayesian probability of projects advancing to successive stages of exploration, eg from reconnaissance, to systematic drill testing, resource delineation, feasibility and mine development, given a successful outcome in any exploration phase. The ratio between the estimated value of the gold discovered and the corresponding historical exploration expenditure in each year and cumulatively, ie the average cost of discovery per ounce of gold, are then computed as measures of historical return on the exploration investment in this belt. These, together with an estimate of the æresidualÆ gold endowment, ie of the number and size of possible as yet undiscovered deposits, generated through the use of rank statistics (ie ZipfÆs law), provide a basis for future strategic consideration in exploration targeting in this and similar geological terranes.

Jan 1, 2009

By T Christie

Tertiary volcanic rocks make up a significant proportion of the surficial cover rocks of New Zealand, especially in the Taupo Volcanic Zone. Industrial minerals that are associated with or derived from the volcanic rocks include: amorphous silica, allophane, bentonite, diatomite, ignimbrite building stone, illite clays, halloysite clay, obsidian, perlite, pumice, sulphur, titanomagnetite ironsand and zeolite. Of these: bentonite, ignimbrite building stone, perlite, pumice and titanomagnetite ironsand have been mined and processed for 20 to 30 years, but many of the others require further characterisation of the resource and/or development of markets.   We have compiled interim mineral deposit models for halloysite clays in rhyolite and for zeolites in altered vitric tuffs. These models include geological and mineralogical attributes, which are linked to the underlying volcanic and geothermal processes that have produced the minerals and their source volcanic rocks. Halloysite clay deposits at Matauri Bay (Northland) have formed from hydrothermal alteration and weathering of rhyolite. Clinoptilolite + mordenite zeolite deposits in the Ngakuru area (Rotorua district) have formed from hydrothermal alteration of volcanic glass in lacustrine sediments and ignimbrite. Further refinement and application of these models will result in a better understanding of the mineralogy, localisation and origin of the deposits, with consequent applications in exploration and resource assessments.

Jan 1, 2001

Copper mineralization associated with minor molybdenum, silver, and gold occurs in a hydrothermally altered brecda within a granodiorite mass of Upper Permian age. A dyke system of rhyolite, dacite, and andesite forms plug-like bulges near the breccia and probably caused mineralization as a late stage effect.Base metal sulphides occur as disseminations, fracture and cavity fillings in the breccia. A pyritic halo in hydrothermally altered granodiorite surrounds the breccia and grades into unaltered granodiorite. Drilling during 1969 indicated the grade is subeconomic.

Jan 1, 1972

This paper discusses the history and development of the system and the benefits that are being gained for Yabulu from Solar Drying. Following the end of mining of the local Greenvale and Brolga nickel deposits, QNI Yabulu Refinery is dependent upon imported ore from over 15 different mines in New Caledonia, Indonesia and the Philippines.

Jan 1, 2003

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 P B. Card

"The website www.economicevaluation.com.au, which had its origins at the Project Evaluation Conference 2009, provides a free way for industry professionals to teach themselves economic evaluation. At its core is a set of fast-moving modules and three worked examples.The website recognises that economic evaluation is a discipline with a hierarchy of three levels:decision-makingevaluating the project/businesshands-on modelling.There are a set of modules for each level that describe the concepts and activities in detail. These emphasise that the most important and rewarding work is the evaluation of Level 2. The economic model created in Level 3 is merely a working tool and should not become a sophisticated ‘trophy’ in Excel that only one or two people can comfortably use.Hands-on modelling contains three sets of practices designed to make any model rigorous and intuitive so that it can be easily understood and used by others in the project team. Even if the model develops into a long, detailed and complex workbook, it should remain easy to follow and be intuitive. The website advocates freedom to devise any architecture that best suits the project under study, but promotes rigour through the following practices:four cash streams and graphsthree architectures – concept, prefeasibility and feasibilitysix principles.The modules in the Level 2 evaluation use conversational language to describe in detail the broad range of activities needed to properly understand and characterise a project/business. It stresses that net present value is nothing more than the mathematical treatment of a whole set of opinions, is not an absolute truth and is only a fraction of the evaluation process. The modules describe in detail the range of economic metrics that should be computed and the full spectrum of equally important characterisations required to make the decision in Level 3.CITATION:Card, P B, 2016. Teach yourself economic evaluation, in Proceedings Project Evaluation 2016, pp 160–171 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

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

By Matters C. W

THE following paper embodies the present practice and the results of past experience in the survey departments of two of the leading Broken Hill mines, the Central (Sulphide Corporation Ltd.) and the Broken Hill South S. M. Co. N. L.The authors intend to limit the scope of this paper to a consideration of office methods, as much has recently appeared in technical literature concerning field work, both surface and underground. Special reference may here be made to a valuable paper on 'Mine Surveying' by H W Gartrell, in Vol XIII of Transactions, in which the author gives considerable attention to field work. Moreover, much of the office work described in current literature is American, and sometimes not suited to local conditions, being ·often exceedingly elaborate and demanding a large staff of assistants. It is believed that the methods of recording information described in this paper are sufficiently simple and flexible to be adapted to most Australian mines. Brief acknowledgement must be made to the work done by Americans, who have raised mine surveying to the position of a separate profession, instead of being merely an unimportant branch of land surveying.

Jan 1, 1912

Circulating Air Classification of Manufactured Sand Due to environmental concerns, the supply and use of natural gravel has been limited by the Swedish government. The Swedish concrete industry is therefore examining manufactured sand as an alternative that has equal or better product quality, and which the Swedish quarry industry already has the ability to deliver. However, in order to comply with the specifications set by the concrete industry, a better means of classification is needed, as the proportion of fine particles (filler) smaller than 63 - 125 ¦m in size must be reduced. One classification technology that meets the requirements may be air classification. This paper examines the process of circulating air classification, which is not yet commonly used in the Swedish quarry industry; suggesting that a better understanding of the process is needed. The circulating air classifier in this study has two internal machine parameters that can affect the separation point; namely, the speeds of the circulating fan and the separator fan. We study their effect on the separation point as well as the interaction between these parameters. Full-scale parameter tests are also conducted, in which size distribution is measured before and after the circulating air classification. This study shows how the different parameters affect the separation point and that it is possible to produce manufactured sand according to specifications. Computational fluid dynamics (CFD, Fluent) is used to study the internal flow of the air circulating within the classifier. A single-phase study of the flow field is conducted to support and explain the findings from the full-scale tests.

Sep 13, 2010