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Mining companies around the world are seeking methods to coordinate operations between the mine and the concentrator to achieve an overall improvement in enterprise performance. In several instances very significant increases in productivity (more than 20 per cent) and profitability (more than $US 10M per annum) have resulted from such efforts. The key to realising these large benefits has for the most part arisen from improved communication between mining operations and plant operations personnel and the judicious use of new tools to evaluate alternatives for improvement and to minimise the risk of implementation. This paper presents a systematic approach to mine-to-mill optimisation . The importance of systemic thinking and systems optimisation methodologies is emphasised. New tools for evaluating operational performance are discussed. Recently reported benefits are summarised. Finally current research is discussed and projections for the future are given.

Jan 1, 2000

Solid Energy New Zealand Limited (æSolid EnergyÆ) is a state-owned coal mining company, producing 4.0 Mtpa from a number of opencast and underground mines in the Huntly, West Coast and Southland regions in New Zealand. The company currently exports 2.1 Mtpa of coking coal. Exports are expected to grow strongly over the next five year as the company expands production into new semi-soft and thermal coal reserves. Domestic coal demand is also expected to grow strongly, particularly in the North Island, as the Maui gas field reserves diminish, and thermal coal becomes more important for electricity generation and meeting the energy needs of forest processing and other industries. Solid Energy is expanding and developing its risk management practices across all areas of the business: strategic planning û extensive use of scenario analysis and probabilistic modelling over a 20 year period; investment decisions û development and application of a rigorous six stage æProject Assessment GuidelineÆ process for all new mine developments; geological and geotechnical risk assessment techniques û use of best practice techniques including seismic surveys; financial risk management û a dynamic approach to hedging based on effects based analysis of Cash Flow at Risk analysis against preset risk tolerances; risk financing û the use of a captive insurance subsidiary, and the experiences of a small coal company seeking to obtain insurance cover on a æhardÆ international insurance market; and integrated risk management û the challenges of trying to implement a broad integrated risk management approach across the company, that supports implementation of strategic objectives as well as meeting æcompliance or legislative basedÆ risk management requirements.

Jan 1, 2003

By C. P. BATES

In November 1969, New Zealand Steel Ltd pioneered the commercial use of the SL/RN solid fuel direct reduction process to make sponge iron as a feed material for electric arc furnaces. Serious process problems with the use of green balls and coal injection were progressively overcome. The process was developed by New Zealand Steel along a radical route, of feeding the fine grained raw ironsand concentrate and coal directly to the kiln. Contemporaneously with this development of direct reduction, steelmaking process innovations were made that enabled the arc furnaces to operate successfully with the high volumes of acid slag.

Jan 1, 1980

By T Higuchi, T Yamamoto, K Takehara

Iron ore fines are used as raw materials for sintered ore for blast furnaces in the world. Since the production and quality of sintered ore have a great influence on the stable operation of a blast furnace, many technologies were developed for controlling the heat profile in the sintering machine, which largely affect the sintered ore properties. In particular, the influence of oxygen in the suction gas, which plays an important role in combustion, was investigated over the years. It is known that increasing the oxygen ratio by about 30 per cent not only significantly improves the combustion rate, but it also increases the strength and yield of sintered ore. However, the details of the mechanism for improving these qualities are unknown. In this study, we investigated the influence of oxygen enrichment at higher ratios (O2: 21–40 per cent) and tried to understand the sintering behaviour enhanced by oxygen. The effect of oxygen enrichment on sintered ore quality and the heat profile were evaluated by sintering tests using a quartz glass pot. From the results, sintered ore yield had a maximum value for O2 = 30 per cent, but strength was increased for O2 = 40 per cent. From heat pattern analysis, it is clear that the high temperature holding time also reached a maximum at O2 = 30 per cent. Furthermore, we found that with increased oxygen ratio, the combustion speed (flame front speed) was increased, but the area of combustion was enlarged. It is considered that there could be a maximum oxygen ratio value for the yield from the balance of these positive and negative effects on high temperature holding time. To clarify the reason for strength improvement, thermodynamic calculations were performed and it was found that melting behaviour could be improved by changing the oxygen ratio.

Sep 18, 2023

By J Ralston, W Skinner, D Fornasiero

The Wark has been conducting collaborative research through the AMIRA International P260 series of projects for over 20 years. This paper reviews specific outcomes of successful technology transfer to flotation plant practice over that time. Moreover, findings of an independent audit of industry users of the research outcomes of the P260 project are reviewed. The key to successful technology transfer is the active engagement of industry personnel at all phases of the technology transfer process. Other research outcomes include the novel application of new measurement tools and methodologies which include, for example, advanced surface analysis techniques. These new tools and methodologies have been pivotal to improving our understanding of factors that limit the flotation separation of minerals at plant scale. Future potential targets for technology transfer to improve flotation plant practice are discussed.

Jan 1, 2009

Although the last decade has seen the growth of many new licencing and approval requirements for the exploration and mining industries, there remains in each State of Australia and the Northern Territory a predominant "Mining Act" containing provisions for the grant of exploration and mining tenements. What then are the rights and duties of tenement holders either by virtue of a Mining Act or through other approval and licencing mechanisms? What rights and duties does a person acquire when he is granted an exploration licence or a mining lease? In this paper I will attempt to cover these types of questions using in particular examples from New South Wales. I will also refer to a range of other subordinate approvals and licences which today's society requires and the need for ethics and recognition of liabilities.

Jan 1, 1995

I began my interest in sample preparation when I joined the Institute of Nuclear Sciences in 1962. I worked in the fields of rock dating and stable isotope geochemistry. Preparing a sample could take several days and the analysis took another day or more, so great care was taken with each sample. In 1968 I changed to mineral exploration analysis and was surprised to find that there was much less care in how a sample was taken and prepared. Virtually every sample was processed in the same way. In the use of ring and puck mills, Australia and New Zealand were among the world leaders. It took another ten years before labs in North America changed over from disc mills. In 1975, my partner and I divided our business into two parts. He took the laboratory into his consulting laboratory business and I took the small business that we had started, making ring and puck mills. For the next six years I was RocklabsÆs only employee. In the 1980s and 1990s, sampling specialists like Francis Pitard and Dominique Francois-Bongarcon began to make a difference in the understanding of what constitutes good sampling and preparation practice. They and others took courses on the new concepts of Sampling Theory, as developed by Pierre Gy. The desire for better procedures lead to the development of new machines, including the big bowl pulverisers from Australia, jaw crushers that could crush finely like our Boyd Crusher, rotating dividers of new designs and flow-through ring and puck mills. Other machines did not fare so well, including rolls crushers, cone crushers and hammer mills.

Jan 1, 2008

Giving the keynote address in the final session of a conference dealing with closely related topics has a disadvantage in that much of what can be said has been said. It also has an advantage, however, because it presents the speaker with the opportunity to integrate and analyse the material presented by the various speakers. I would like to look to the near future in Aust- ralia and the United States of America, to the risks, problem areas, and changes of a rapidly evolving post-industrial era-an era we are begin- ning to experience where industry no longer `calls the tune'. We miners have been quick to point out and emphasize, that ours is a `high-risk' industry in the world of business and commerce. Yet, clearly those who have survived, and been successful, have learned to anticipate and cope with risk and change. This ability has been a distinguishing feature of the industry's leaders who, in market studies and commodity selection, exploration and development, mine planning, metallurgical pro- cessing, and general administration and operation 1. identify areas of risk or inevitable change, 2. analyse, test and quantify those factors of risk or change, and 3. design methods, systems, equipment to elim- inate, moderate, or control or economically compensate for predicted risks or changes.

Jan 1, 1978

By Hagarty KA

At the northern margin of New Guinea there is a fundamental problem related to the relative timing of arc- continent collision(s) represented in the Papuan Fold-Belt (PFB) and backarc spreading in the Caroline basins. New fission track dates from basement and sediments within major anticlines of the PFB indicate that uplift occurred at 4.0 ¦ 0.5 Ma. The timing is consistent with the fold and thrust shortening (more than 100 km) of the PFB which occurred in the Late Miocene/Early Pliocene as evidenced by the deformed Miocene carbonates and Pliocene molasse deposits. However, in northern Papua New Guinea, earlier work has suggested that ophiolite emplacement and associated metamorphism occurred in the late Oligocene/early Miocene.The evidence suggests that the late Miocene/early Pliocene deformation was of considerably greater magnitude than the earlier obduction event. The Caroline Plate lying north of New Guinea has been interpreted as a backarc basin which commenced spreading in the Eocene and ceased spreading in the Late Oligocene (about 28 Ma). The remnant arc presently docked to New Guinea was active in the Eocene and Oligocene and is believed to be the arc related to the formation of the Caroline Plate. The cessation of spreading of the Caroline Plate has previously been interpreted to be due to arc continent collision during the Late Oligocene/Early Miocene, but such a collision is now known not to have occurred. In the Cretaceous and Palaeocene subduction was to the south beneath New Guinea, but "flipped" in the Eocene to give a north-dipping subduction zone far to the north of New Guinea, driving Caroline Plate backarc extension. This backarc basin reached a limiting size at about 28 Ma resulting in the end of subduction. With the continued northward movement of Australia, Mesozoic oceanic crust was obducted southward onto the New Guinea margin in the Late Oligocene/Early Miocene. In the Miocene south-dipping subduction beneath New Guinea commenced until the now extinct Caroline Plate arc collided with New Guinea in the Early Pliocene, causing extensive regional compression and sinistral strike-slip faulting. This new tectonic framework suggests that backarc basins reach a limiting ridge-trench distance of 1000-1500 knm, beyond which "subduction-pull" cannot drive further spreading so subduction and spreading are terminated.

Jan 1, 1987

Mt Todd lies towards the south end of the Pine Creek Geosyncline, sandwiched between the Cullen Batholith and the Edith Falls Basin, in an area of regionally metamorphosed sandstones, siltstones and shales. The Batman deposit, some 3 km west of Mt Todd is a sheeted quartz vein system hosted within greywackes of the Palaeoproterozoic Burrell Creek Formation (Finniss River Group). The gold-bearing quartz veins, trending 010¦-020¦ and dipping 60¦-70¦E, are commonly 0.5 to 5 cm wide and occur at intervals which are from 10 cm to 1 m apart. Gold tends to be restricted to the quartz veinlets and immediately adjacent country rock. Grade Control utilises two 4 m 'collar' samples which are collected from each 8 m production blasthole. The irregular distribution of the quartz veins and erratic gold mineralisation has resulted in a disseminated 'salt and pepper' type of gold occurrence, with only a poorly defined footwall. Delineation of ore and waste blocks for mining uses an approach which combines the smoothing effect of kriging with a pragmatic view of the raw data. Large ore blocks with simple geometry help to minimise mining dilution, reduce block variance and give good reconciliations to interpreted ore tonnes and grade. Daily mine face advance is reported against truck counts and provides continual comparison with budgeted production. All data processing uses Gemcom software, together with Lotus spreadsheets.

Jan 1, 1994

An Investigation on the Effect of Chrysotile Particle Shape and Anisotropic Properites on the Rheology of Chrysotile Suspensions Chrysotile, a polymorph of serpentine, is a phyllosilicate mineral that occurs as a major gangue mineral in many ores (eg Mt Keith nickel sulfide ore, Western Australia). The rheological behaviour of chrysotile stems from two main factors: its distinctive morphology and its electrical surface charge. It is believed that these factors are central to the problematic rheological behaviour and low solids throughput typically experienced in the processing of such ores. In this work, a study of the effects of chrysotile surface charge properties and particle shape on the rheology of chrysotile suspensions was conducted. It was found that the rheology of suspensions of pure chrysotile is characterised by extremely high yield stress values over a broad pH range (pH 4 to 11).The disparity in the point of zero charge and range of maximum yield stress for chrysotile is consistent with the anisotropic nature of chrysotile particles. A comparison of the rheological behaviour of quartz suspensions (non-fibrous) to that of chrysotile suspensions (fibrous) provides a practical indication of the effects of the fibrous nature of chrysotile relative to non-fibrous minerals. The long, thin fibres are easily entangled to form suspensions with much higher plastic viscosities and Bingham yield stresses than non-fibrous particles. Chrysotile particle shape and surface charge are central to the rheology of chrysotile suspensions, although shape appears to play a more significant role in this regard. This fundamental study would be beneficial to the ongoing research for improved recovery in the Mt Keith nickel sulfide ore as well as other chrysotile bearing ores.

Sep 13, 2010

By M Kuruppu

Large mining operations require a high percentage of the capital invested in mobile and fixed mining machinery. From an investment point of view this expenditure must be met by an equally high rate of return, thus the need for high plant and equipment reliability is of major importance. Equipment downtime is undesirable and very costly, resulting in lost production and revenue, which is of critical importance to successful mining operations. One of the solutions to this problem may be found in the form of competent computerised maintenance management software systems, which help to reduce the problem of breakdowns. These software assist the engineers for the management of service orders, resource allocation, progress monitoring as well as costing. They also facilitate the communication of targets and objectives among the service personnel. A computerised maintenance management software called MAINPAC was used to record and plan the activities of mobile equipment maintenance in a large mining operation in Western Australia. Among the details recorded were equipment data, service history, machine downtimes, previous maintenance, job planning and the resource required. This information further helped to analyse the maintenance efficiency, availability and the reliability of the equipment.

Jan 1, 2006

By C Linklater, A Garvie, D Kentwell

Various Australian and international regulatory bodies (Environmental Protection Authority, 2015) require an early assessment of the geochemistry of waste rock. This usually includes estimates of the locations and volumes of potentially acid forming (PAF) materials and requires sampling of the waste rock zones as well as submitting the samples for a series of tests. We know that the required number of samples will vary depending on rock type, mean sulfur levels and spatial variability of sulfur as well as total volume. The key question is how do we know when we have enough samples?This extended abstract describes the application of geostatistical methods to examine how sample numbers and sample locations influence the preliminary conclusions that may be drawn for early stage waste characterisation.CITATION:Kentwell, D, Garvie, A and Linklater, C, 2016. Geostatistics and sample numbers from an acid and metalliferous drainage perspective, in Proceedings Life-of-Mine 2016 Conference , pp 12–15 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By McNabb K. E

Significant coal reserves in New South Wales lie under areas with steep topography such as valley slopes and cliffs. Subsidence predictions are difficult to make for these locations as existing empirical databases cannot cover all permutations of topography and mining geometry. Two dimensional numerical model alternatives are of limited applicability. Consequently a novel three-dimensional numerical model is developed including the detailed panel layout, realistic rock mass properties including the full stratigraphy, goaf behaviour and actual surface topography. Model results show the same trends as subsidence measurements from Baal Bone Colliery in the Western Coalfield of New South Wales.

Jan 1, 1992

By P Louden, C Rothnie, G Showers

Tiwest employs several methods to assess the quality of heavy mineral concentrates in ore and process samples. Mineralogy is determined using a method called MA98, developed in conjunction with JKMRC over the last three years (Zhang and Whiten, 2001). A range of other techniques are also used to characterise ore, heavy mineral concentrates and mineral products. MA98 is the culmination of efforts since 1989 to determine mineralogy from chemical analysis without recourse to heavy liquid fractionation, which has traditionally been used to discriminate between light-heavy , zircon, rutile and leucoxene. The major advance with MA98 is the use of statistical mass balancing for all chemical species, as opposed to reliance on key chemical species for each mineral. Three magnetic fractions are analysed by X-ray fluorescence spectrometry, with a minerals balance performed for each. Heavy mineral concentrates processed by this method include drill samples, process samples from the wet concentrators and Dry Mill, and mineral products. TBE can be avoided for higher heavy mineral grade samples since quartz is determined from SiO2 balance. In this sense the method is sufficiently universal and robust to cope with a wide range of sample types and compositions. The MA98 algorithm provides abundant information in addition to mineralogy, including TiO2 and Fe2O3 grades of ilmenite and leucoxene, and concentrations of weakly magnetic zircon and kyanite. Information such as this is invaluable in tracking different minerals through the processing plants. Other ore assessment procedures used by Tiwest provide for modelling of orebodies by mineral sizings, Fe in zircon, and FeO and U+Th in ilmenite. Microscopy is used to provide important qualitative information such as grain shape, surface staining and degree of cementing. These quality measurements are included with mineralogy in geological ore models and are available for mine scheduling. In using the above methods to characterise heavy mineral concentrates, Tiwest is better placed to predict and monitor plant performance and product quality from any ore zone.

Jan 1, 2001

By A Giblett, M Daniel

"The Global Mining Standards and Guidelines Group (GMSG) currently supports nine individual industry working groups focused on developing standards and guidelines for the mining industry. In 2013 the GMSG established the Industrial Comminution Efficiency (ICE) working group to develop freely available guidelines for plant operators to quantify the operating efficiency of industrial comminution circuits. This initiative has engaged a diverse group of representatives from mining companies, equipment vendors, consultants and metallurgical laboratories with vast experience and capabilities in the field of comminution. The GMSG has issued the first two guidelines from the ICE working group in 2015–2016, with the third guideline having completed the approvals process and being in the final stages of editing ahead of release later in 2016.Two of the ICE guidelines present methods to quantify comminution circuit efficiency, and a complementary guideline describes best practice methods to collect the necessary samples and data to furnish these assessments. Collectively the guidelines cover sampling, survey data collection, laboratory testing procedures and calculation processes to allow the user to generate a relative circuit efficiency factor for the comminution circuit at the time of survey. The reference energy consumption is calculated considering the measured F80, P80 and ore strength at the time of survey, using either or both of the Bond or Morrell methods presented in GMSG guidelines dedicated to each method. The guidelines consequently provide the end user with practical tools to perform circuit efficiency analysis and to readily quantify the impact of optimisation efforts.This paper presents the content of the three ICE guidelines and describes their intended application.Citation:Giblett, A and Daniel, M, 2016. Global Mining Standards and Guidelines for Determining Comminution Circuit Efficiency, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

Some fundamental aspects of recent single-particle fracture studies are reviewed. Findings from this research shed new light on the utilisation of energy during comminution operations and provide useful pointers to new research directions that could lead to significantly better comminution machines. Two methods for quantitatively predicting mineral liberation during comminution are reviewed. These methods have been developed into useful practical procedures, but they are almost unknown in the mineral processing community. Their use should promote the consideration of mineral liberation as an important variable to be considered during the design and operating control of comminution circuits.

Jan 1, 1993

By Tyler MA

If the record of maj or proj ects in Australia is taken into account, it is apparent, the proper planning of an industrial relations strategy for many such projects has been ill considered by project developers. The recognition of the need to develop a plan from the initial feasibility study has been forced on those promoting new projects by the publicity given to the Australian industrial relations record. The delays in delivery caused by factors supposedly out of the project's control are often given for non-performance of contract and used as an excuse for limiting further development. Many of the problems experienced in project development can be overcome with sound industrial relations planning. The promises given in the euphoria of the early stages of a project relating to price and delivery often become a burden for the future because the complexities of the Australian Industrial Relations Systems are not understood or considered. The recognition by senior executives of their responsibilities in this area will contribute greatly to a new era of project development.

Jan 1, 1983

The majority of coke in Australia is made in by-product slot ovens at steelworks in Port Kembla, Newcastle and Whyalla. Most of the coals for these plants come from New South Wales but a regular proportion of Queensland coals may be introduced. The plants and the coals are reviewed in the paper.

Jan 1, 1975

The paper describes the development leading to the bucket wheel excavator systems now used in the Latrobe Valley and refers in particular to the new S.E.C.V. dredgers Nos. 14 and 15 which will be employed in the Loy Yang open cut. The design concept and operating possibilities of these dredgers are described in detail with reference to the machine characteristics designed for the operating conditions in the Latrobe Valley. The design is compared with units of similar capacity in open cuts of other countries.

Jan 1, 1982