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By Kasai H, Hibi T, Matsuishi S

Coal oil mixture (COM), a liquid fuel pro- duced by mixing together coal and heavy oil on the 50-50 basis, has been brought to a level of practical use in Japan, being actually employed by a oil fired system at Yokosuka Thermal Power Station of The Tokyo Electric Power Co., Inc. A COM Production Plant, built in Onahama which is located about 160 miles from Yokosuka, required COM to be transported by sea. Mitsubishi Heavy Industries, Ltd. therefore performed a series of studies to develop a spe- cialized COM carrier, the world's first of its kind. Long lasting high stability is of pri- mary importance to successful use of COM. Much have been done in the way of research on stability of COM in the static storage, and the mechanism of COM static: stability is almost completety known. On the other hand, the knowledge about the COM dynamic stability, such as the stability while being transported aboard the COM carrier at sea, is still limited at the moment. The motion of COM aboard the COM carrier and how COM would settle were studied by tests. A visualization test on the COM behavior under dynamic motion was also performed and the mechanism of COM dynamic stability was analysed. The tests showed that the ship rolling motion had @n effect of promoting the settling of coal content of COM in the cargo hold. And studies were also made to device a method for esti- mating the settling quantity of coal during sea Transportation.

Jan 1, 1987

By Ramani R. V

In this paper, a comparative performance evaluation of geostatistical, spectral, and fractal methods is made for short-scale variability prediction. The algorithms compared are: sequential Gaussian simulation method; a random fractal algorithm based on the generalised stochastic subdivision method; and a spectral simulation approach adopted for direct multi-dimensional simulation. The data for this study have been obtained from a mined out coal property. As this property was being mined, a 7315 m by 7315 m (24000 ft by 24000 ft) coal block was extensively sampled at an approximate spacing of 107 m (350 ft) and the 60-ton samples were analysed for sulphur in the 1.50 float gravity fraction. This data set is used here with the three methods to generate the simulated realisations, which are analysed for semivariogram reproduction and for simulation errors. Although all three methods converge to the true semivariogram in an average sense, the coefficient of variation of the average semivariogram for the Fourier integral method is minimum. The realisations generated by the sequential Gaussian method have minimum mean simulation error. The choice of a simulation method based on variability reproduction and simulation errors remains difficult.

Jan 1, 1995

Waihi Gold Mining Company Limited, a wholly owned subsidiary of Normandy Mining Limited, operates the Martha gold mine, located in the township of Waihi, New Zealand. The operation, an unincorporated joint venture, comprises Normandy Mining Limited (67.070/0) and Otter Gold Mines (32.94%). Since gold was first discovered at Waihi in 1878, it has formed a key part of the region's economy. In 1909 the Waihi mine was described in a report to Parliament as æthe most important gold mine in Australasia and one of the greatest in the world.Æ That was a record year for production, with 416,813 tons of ore mined and some 1,120 men employed. Today the mine produces up to 1,250,000 tonnes of ore annually, and the project employs some 234 men and women. In 1999 the value of the gold and silver produced ($59 million) made up 47% of Waihi's estimated GDP. Waihi Gold has made significant contributions to the Waihi economy, community and the Hauraki region as a whole. Since the mine was re-opened in 1987, thousands of local people have benefited from the mine. In 1999, consents were granted allowing an extension to the mine life (the Extended Project) and this will result in a further seven years of economic benefits resulting from mining activity. The Company has undertaken extensive consultation throughout project planning, construction, operations and rehabilitation. Ongoing liaison and involvement with all community sectors, including Tangata Whenua and Iwi, local residents, recreational groups and schools remains an integral part of the operation. Throughout the life of the modern Martha Mine, the Company has actively supported the local community in the form of donations, sponsorships, the provision of amenities, and by participating in community events. A well established environmental team exists at the site. Environmental and community performance is measured by an independent five-assessment process, and the Company is committed to achieving excellence through ongoing improvement programmes and staff awareness. When the mine is closed, the open pit area will be transformed into a recreational lake, and the tailings storage facilities will be rehabilitated to become a combination of wetlands, grassed areas and ponds. Resources will be provided by the Mine to ensure the rehabilitated site remains in a safe and self-sustaining, stable condition in perpetuity. The mine is regarded as a showcase on a world standard of how a modem mining operation can successfully coexist with the nearby community.

Jan 1, 2000

The Favona Underground Project is located approximately two kilometres east of Martha Mine Open Pit in Waihi, 150 km south east of Auckland, New Zealand.   The underground reserve of 354 koz Au contained in resources of almost 600 koz lies within 600 m of the existing process plant presenting an attractive development target in a challenging environment.   The Martha Mine Open Pit is surrounded by urban housing on the north western edge of Waihi township and the Favona Underground abuts residences on the eastern edge of town. Environmental, community and social licence aspects influence project strategies as the new underground mine extends mining in a town that is planning for closure of current open pit operations in late 2006.   The Favona Underground Project has successfully passed through a detailed feasibility study, the third stage of the five stage Newmont project appraisal system. Methodologies used in the feasibility study and parallel permitting draw on a high level of stakeholder involvement to streamline the development and permitting phases.   This paper discusses the project appraisal process and design innovation required for developing an underground mine adjacent to town.

Jan 1, 2004

By M W. A Asad, E Topal, D S. S Sandanayake

Underground mine planning requires an optimal stope layout as a prerequisite for the definition of an optimal production schedule. The procedure to generate an optimal stope layout considers an orebody model and economic parameters as inputs. It evaluates all possible combinations of mining blocks and creates a set of stopes by satisfying the physical mining and geotechnical constraints. Thus, the procedure is computationally complex, and generating a solution to the problem is a challenge. This paper presents an implementation of a new heuristic algorithm that solves the stope layout problem. In two case studies, the algorithm achieves 11.2 per cent and 22.5 per cent superior solutions to the industrially available maximum value neighbourhood approach.CITATION:Sandanayake, D S S, Topal, E and Asad, M W A, 2014. Implementing a new heuristic approach to the underground mine stope layout problem, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 243–248 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

The Tom's Gully gold mine is located 90km ESE from Darwin, in the Northern Territory of Australia. The orebody is the auriferous portion of a large sulphide rich quartz reef, hosted in the Wildman Siltstone Formation of the Early Proterozoic Pine Creek Inlier, at the NH extremity of the Mount Bundey granite-syenite intrusion. It was discovered by Carpentaria Exploration Company Pty Ltd on November 17th, 1986, using stream sediment geochemistry.The reef is 800m long at surface, strikes E-H and dips approximately 300 to the south, becoming progressively less steep. Only the eastern half of the reef is auriferous, with gold grades averaging 9 g/t plus anomalous silver, base metals and arsenic.The enclosing siltstone is a dark grey banded carbonaceous and pyritic metapelite, showing areenschist regional metamorphism and thermal effects from the adjacent pluton. Local folding plunging gently SW is cut by a south dipping fault, probably a thrust, in which the reef was later formed at about the time of the granitic intrusion. The main sulphides in the reef are pyrite and arsenopyrite, with gold occurring as microscopic particles in...

Jan 1, 1990

The object of this paper is to give an insight into various metallurgical operations involved in the making and shaping of steel for shipbuilding at the Newcastle plants of the Broken Hill Proprietary Co. Ltd., Commonwealth Steel Co. Ltd. and the Port Kembla plant of Australian Iron and Steel Ltd. Whilst not steelmakers, inasmuch as their processes start with semi-finished. steel supplied by the Steelmaker, the plants of Stewarts and Lloyds (Aust.) Pty. Ltd. and their associate company, British Tube Mills, Rylands Bros. (Aust.) Pty. Ltd. and the Newcastle and Kembla plants of John Lysaghts (Aust.) Pty. Ltd. make substantial contributions to the Australian shipbuilding industry, principally by way of boiler tubing and wires for welding rods and sheet steel, including special silicon lamination sheet for electrical motors.THE MAKING OF STEELThe making of iron and steel began as an accident, slowly developed as an art and has not yet become an exact science. The iron age dawned on the day when, by chance, man's primitive ancestor built up the wall of his fire with ironstone. In the ashes of the fire he found pieces of sponge iron from which he hammered out the first sample' of wrought iron. For many centuries iron ·was manufactured in bloomeries and occasionally, when the temperature was excessive, the iron combined with some carbon and steel was produced. But it was not till '1740 that steel was manufactured under controlled conditions. In that year Huntsman invented the crucible process which held undisputed sway for over a 100 years until in 1856 the invention of the Bessemer process revolutionised the whole industry.From then on, rapid progress was made. The Siemens...

Jan 1, 1951

By Roberts AW

Bulk materials handling operations depend on efficient storage and gravity flow facilit- ies. ,It is important that proper attention be given to the complete storage bin or stockpile and feeder combination. The paper briefly des- cribes the principles of efficient feeding and discusses the common types of feeders under practice. While ideally unaided gravity flow should be sought, occasions arise where flow promotion is necessary. Various types of flow promotion devices are described and their operational features evaluated.

Jan 1, 1978

FOR some years after the erection of the first chlorination plant at Mount Morgan the ore sent to the works for treatment was mined entirely from the oxidized zone; consequently, the bullion recovered at the refinery was of unusual purity, averaging about 972 in fineness, and, as no impurity in any way detrimental to the softness or toughness of the bullion was present, there was no necessity to subject it to any refining process.The charcoal from the filters was calcined to ash in small reverberatory furnaces of the usual type. The ash was mixed with suitable proportions of soda and borax to form a good liquid slag. This' mixture was then charged into salamander cruciblesand run to metal and slag in the ordinary wind furnaces-a slow and tedious proceeding in the Mount Morgan climate. The bullion, cleaned of slag, was re-melted under borax and poured into bars weighing from 350 to 400 oz.; these bars, after being dipped while hot into dilute sulphuric acid, were packed and sent to the mint. Of late years, however, the ore coming from the deeper ground of the oxidized zone became much lower in gold values, and contained variable but increasing quantities of sulphides, sulphates...

Jan 1, 1911

By S J. Tear, L D. Queen

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Frieda River Project is located in the north-west of Papua New Guinea. The target commodities for a bulk mining operation are copper and gold associated with a large felsic porphyry system. The project comprises a series of deposits, with the Horse-Ivaal-Trukai (HIT) being the largest. It also includes the adjacent smaller Koki and Ekwai deposits.Previous resource estimates for the HIT were made using 14 separate mineralised domains based on structure, copper grades, lithology and alteration. H&S Consultants (H&SC) has revisited the deposit and concluded that a simpler methodology could be used for resource estimation without using wireframes as hard domain boundaries. This conclusion is based on reviewing all the available geological data combined with geological and resource experience of porphyry deposits.It is generally acknowledged that porphyry deposits form by diffusion of mineralising fluids through the host lithologies, meaning that sharp boundaries are unlikely unless these fluids encounter specific physical or chemical boundaries. It is important to prepare a comprehensive geological model prior to attempting resource estimation as it forms the framework for the estimates; however, not all geological features may be relevant to the distribution of mineralisation and there can be a tendency to overcomplicate the estimation process by using too many domains. Unless a hard boundary can be identified consistently and unequivocally, it is generally better not to use a boundary in that location.H&SC completed unconstrained models with no top-cutting using both a simple flat search ellipse and a steep search ellipse to generate global resource estimates reported within a predetermined pit shell at a 0.2 per cent copper cut-off. Both outcomes are within 10 per cent for the tonnes, contained copper tonnes and gold ounces compared to the constrained resource estimate. The slight differences are most likely due to the different search strategies, but also indicate the robustness of the unconstrained modelling approach.CITATION:Queen, L D and Tear, S J, 2015. The Frieda kiss – keeping it simple , in Proceedings PACRIM 2015 Congress, pp 361–368 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

A review of the most widely used global extraction sequences in sublevel is undertaken. The review includes techniques used to extract massive as well as single or multiple steeply dipping tabular orebodies. The paper also deals with thick flat lying orebodies suitable for open stoping. Techniques used to minimise the effect of stress redistributions on a global scale are discussed for all the extraction sequences analysed.

Jan 1, 2003

By G Marling, A Calderon, J Harris, P Kirsch, M Shi, D Sprott, A Kirsch

Large-scale infrastructure construction needs to comprehensively manage risks that can impact the health and well-being of many people, from workers (temporary, contracted or full time), to families and surrounding communities. This paper starts with an analysis of incidents (injury, fatality, other damage) in tunnel construction between 2000 and 2014 and assesses the distribution of these events by continent, year, and severity of outcomes. These incidents are then analysed and mapped to a framework of hazards derived from RISKGATE (2014). A comparative register of current tunnel construction risk management guidance is derived from current Australian codes of practice and this register is also mapped to the RISKGATE framework of hazards to identify where coal industry knowledge may offer utility to the tunnelling industry.An initiative of the Australian Coal Association Research Program (ACARP), RISKGATE is an interactive online risk management system developed to assist the mining industry in implementing continual improvement in the management of major unwanted events. To date, a comprehensive knowledge base has been captured for risk management of tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives, outbursts, coal bumps and bursts, human/machine interface, manual tasks, slips/trips/falls, inrush and occupational hygiene. By capturing operational knowledge from industry experts, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover in the coal industry.This paper proposes and outlines how knowledge within the RISKGATE platform could be applied to managing the significant health and safety risks associated with tunnelling. The authors suggest that to varying degrees the knowledge already captured in RISKGATE is likely to be transferable to tunnelling construction operations. Please note that this paper focuses on tunnel construction and does not address risk management of tunnels in operation (eg road transportation or utility networks).CITATION:Kirsch, P, Kirsch, A, Calderon, A, Marling, G, Harris, J, Shi, M and Sprott, D, 2014. Management of health and safety in tunnelling – application of Australian coal mining knowledge, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 563–572 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Sheaves are a critical safety component in a winding system and are expected to survive such extreme loading events as rope break. Sheave designs have often been developed and evolved empirically, consequently many existing sheaves are not necessarily subjected to the detailed analyses that are possible using todayÆs design tools. The design philosophy for sheaves is that the rope should be the weakest link in the system so that associated equipment can function safely for any load up to rope break. A number of failure mechanisms must be considered, but buckling is often prominent. During the course of investigating the feasibility of upgrading the hoisting capacity of a winding system, the capacity of all critical components was reviewed. The sheaves in the system were found to have insufficient spoke buckling capacity for the specified rope. A proposal to increase the spoke buckling capacity by connecting spokes together using a simple tie arrangement was evaluated and found ineffective. An alternative tie arrangement concept was developed and evaluated and shown to be adequate. This paper describes the finite element model, analysis approach and results for the original sheave and the two modifications. The contribution of the sheave rim to the total buckling capacity is evaluated. Some practical issues for spoke tie modifications are discussed.

Jan 1, 2005

The Chamber of Minerals and Energy of Western Australia Inc (CME) is the peak resources sector representative body in Western Australia. The paper gives a summary of the role and objectives of the CME, including its history, structure and key program areas. Particular attention is given to the role of the CME in the Eastern Goldfields of Western Australia. The paper details the types of CME membership that are currently in existence. The paper argues that a strong and vibrant CME is vital to secure the resources sectorÆs growth and development in future years.

Jan 1, 2006

By B Clements, G Lane

The operations and project environments are very different, but overlap in many areas. The development of mineral processing projects is goal oriented, is schedule focused and is a contractual environment. The operating environment for a mineral processing plant is oriented around longer-term commitments, focused on delivery against budget expectations, and an environment heavily influenced by long-term personal relationships, community relationships, and people issues.Further contrast is evident in the way expenditure is managed. Projects commit large amounts of money quickly to meet schedule-based objectives. Operations manage expenditure to minimise operating costs and are able to, or are forced to delay decisions on large expenditures. However, these two environments need to come together in many ways, ranging from greenfields plant handover to a new operations and maintenance crew, to day to day interaction and management of brownfields projects, often in close proximity.This paper considers the different perspectives people bring to projects and early operations, including the advantages and disadvantages of æoperationsÆ input to a project and models for managing value adding during project development, implementation and debottlenecking.CITATION:Lane, G and Clements, B, 2012. Operations versus projects - How do people think and what are the implications?, in Proceedings 11th AusIMM Mill OperatorsÆ Conference , pp 11-16 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By M Oyarzún

Direct relationships between rock texture and BWi (grindability index) have been established based on geological and metallurgical information supported by optical microscopy observations, gathered from 731 samples.Each recognised rock texture is observed to be related to a certain BWi range and, this texture is also characteristic of distinct lithological subunits (recognisable at mapping scale). Therefore, this relationship may provide an important tool for early milling in situ estimation.Since each textural type is a response to rock formation conditions, the causality of the relationship between BWi and texture is based on such conditions and, particularly, on the interfacial free energy among its components.According to the abovementioned textural features, the greater the free interfacial energy between mineral components, the greater the necessary energy required to break its grain boundaries and, consequently, the greater the necessary energy required for milling.If the textural evidence indicates that the rock was able to adjust the shape and/or size of its components – in a natural tendency of all systems to minimise energy– then the necessary energy required to break its grain boundaries will be lower.

Sep 5, 2011

By Yambu J, Titus K

Geotechnical investictations and monitoring have been integral to development of the Porgera Gold Mine. The steep, unstable terrain has required a program for monitoring of slopes and foundations which includes survey stations, borehole inclinometers and piezometers. Case studies of the Maip Pass landslide, Yakatabari land-slide, Anawe Plant Site CIP pond excavation and batter, and a load test study for mine waste dumps are presented.Monitoring is needed to ensure that geotechnical risk is kept to a minimum. A vigilant program will be required for the life of the mine.

Jan 1, 1994

By H Dehghan Jan Abadi, K Shahriar

The iron ore district of Gol-e-Gohar (GEG) is located 60 km south-west of the city of Sirjan, in the Kerman Province of the Islamic Republic of Iran. Six exploration targets have been identified and iron ore has been mined from one area with dry and wet concentrate products sold. Prior to mining commencing in 1999, the proven reserves were estimated at 265 million tonnes (Mt) in 2004 and 40 Mt of 100 Mt overburden has since been mined. Of the six exploration targets, the largest anomaly in the GEG district is Deposit No 3. This paper discusses economic considerations focusing on mine extraction and construction of a concentration and pelletising plant to process ore from Deposit No 3 of GEG. Planned capacity of 10 Mt product (concentrate and pellet) per year is targeted to commence in 2011, and nominal capacity by 2014. The economical evaluation and analysis is one of the most important stages in the feasibility study of mine development. Financial calculations including the provision of financial resources, operation period revenue, loss and profit statement, cash flow, net cash flow, internal rate of return and net present value have been undertaken as part of the feasibility study. The feasibility study operating plan assumes a large open pit mine containing proven reserves of approximately 250 Mt. The feasibility study assumed an economic return of $80 per tonne iron pellet. The economic study determined that Deposit No 3 of GEG can be economically developed by open pit mining followed by magnetite separation and flotation to generate iron concentrate and pellets.

Jan 1, 2007

By D Oliveira

The use of an equivalent continuum for a rock mass is not always suitable for situations where the failure is structurally controlled by discontinuities as in the case of wedges in the tunnel roof. In these instances, discontinuum approaches are usually preferred. Rock joints that are filled with soft infill are likely to be the weakest planes in a rock mass, having a dominant influence on its overall shear behaviour. In this case, the joint material model adopted for the discontinuities should be able to describe important mechanisms, such as asperity sliding and shearing, post-peak behaviour, asperity deformation, and the effect of the soft infilling. The latest version of a soil-infilled joint model is discussed here. It describes more comprehensively than previous models the occurrence of dilation and compression with lateral displacements, and also represents the hardening mechanism related to asperity interference as observed in the laboratory that cannot be readily captured by the existing joint models. An analytical approach for the analysis of rock wedges structurally controlled by soil infilled joints is presented.The analytical approach presented in this paper for assessment of symmetric rock wedges in the roof of a tunnel demonstrates, that the peak shear strength of the joint may not be fully mobilised before detachment of the wedge. The analysis verifi ed that an overestimation of the factor of safety may be observed when an elastic-perfectly-plastic joint model was assumed, whereas the computed maximum factor of safety was considerably less when adopting an appropriate soil-infilled joint model.

Mar 8, 2011

By C K. Suzuki, J A. Yanaguizawa, D M. F de Santana, L R. P Leite, A H. Shinohara

In the present work, the microstructure and mechanical properties of structural mortar from glass insulators were studied by X-ray fluorescence, X-ray diffraction, infrared spectroscopy, microhardness and compression testings. The investigated glass insulators were manufactured between the 1960 and 1990 years and had been used in 230 kV transmission lines. The results evidenced that the structural mortar of glass insulator was replaced from Portland to aluminous cement along the years. The crystalline phases of the mortar were identified and mechanical properties were correlated.

Jan 1, 2008