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By Q Xin, X Shengming, C RuÆan, Z Zhigeng a

The optimum defluorinating conditions for Sichuan bastnasite crude ore were determined by orthogonal experiments. Over 95 per cent fluorine in the crude ore was stripped by roasting 30 minutes of the crude ore with Na2CO3/ore =0.25 at 650oC. The stripped fluorine crude ore was further treated by NH4 Cl to recover rare earth. Above 95 per cent rare earth can be leached by water after the stripped fluorine crude ore mixed NH4Cl(NH4Cl/ore =1:1) roasted 1 h at 325oC. At the same time, the rare earth leaching solution contains little Fe, Si and Al. Therefore it is propitious to further purify the solution and recover rare earth.

Jan 1, 2000

By I Kolomaznik

Each technological process can be reduced on the transport networks, and namely on the parametric networks and the non-parametric ones. The parametric networks are created by the piping, electrical cables or channels. The non-parametric network is created by the ways, suspended grooves, trackages and also by the belt conveyors or other conveyors for continuous material transport. If we reduce the technological process on transport networks, then, by the creation of these networks models and their mutual interconnection we obtain the model of the whole technological process. The model can be understood as the universal one, without exaggeration, because it is valid for any technological process. However, for us the mining production process is important what represents the mining and transport of raw materials under the support of the ensuring system. In this contribution one of the first attempt is described, and namely how to connect the parametric network which has been already worked out very properly with the non-parametric network what is presented in this contribution by the transport line of belt conveyors.

Jan 1, 2003

By S Marsters

Imerys Tableware New Zealand Limited has mining rights to four deposits of halloysite, which are located about 203 km north of Auckland, New Zealand. These primary deposits were formed by the hydrothermal alteration and weathering of rhyolite domes. Halloysite clay is currently being mined from two of these deposits and then processed for export markets. From humble beginnings in the mid 1950s, the Northland halloysite was processed initially for paper filler markets and then for higher value tableware and technical ceramic niche export markets. The paper will briefly cover the geology and processing of halloysite and then examine the history of New Zealand China Clays Limited, now Imerys Tableware New Zealand Limited and then look to its future as part of global industrial minerals company, Imerys.

Jan 1, 2002

The firing of mass blasts at Isa Mine is a normal operating practice. Both electric and non-electric initiating systems are being used for this purpose. The advantages gained by large firings relate to the Planning, Scheduling, Services and Production functions of Isa Mine. More efficient us"e is made of manpower due to the concentrated charging effort and con- tinuity of the charging operation. In addition, the requirement for ring firing personnel to work at the edge of large stope voids is reduced. Better fragmentation results from the interaction of adjacent detonating rings of blastholes and in flight collisions. With mass blasts there is also less chance of large blocks of ore, created by faults or joints, falling into the stope and creating problems at the drawpoints. The formation of a large tonnage of broken ore facilitates production at scheduled rates from that stope source. The weight of explosive detonating during a mass blast can be considerable. Isa Mine has achieved satisfactory blasting results without excessive ground vibration levels and present knowledge indicates that pillar ground stab- ility has been maintained.

Jan 1, 1978

The need for the hydraulic transportation of coal in the New South Wales coal industry, both from the coal face to the surface and from the coal mine to the consumer or the port for export, is explained. Details of research projects currently in progress and involving the hydraulic transportation of New South Wales coals are given together with information on the hydraulic transportation of coal in the United States of America. The potential of hydraulic transportation as a viable alternative to the proposed expansion and upgrading of the New South Wales railway system to meet the projected New South Wales coal production to the year 2000 is described.

Jan 1, 1980

As the Mount Morgan electrolytic chlorine plant is the first of its kind installed in Australia, and as the details of this method of producing chlorine have, up to the present time, been kept more or less secret all over the world, the author trusts that this paper may fill a gap in the technical literature of the subject.When an electric current is passed through a strong solution of sodium chloride the following reaction takes place -2 NaCl + 2 H 20 = 2 NaOH + C1 2 + H 2 Chlorine gas is liberated at the anode or entering pole of the current, while caustic soda and hydrogen are formed at the cathode or leaving pole of the current. If the two electrodes be simply immersed in a vessel containing salt and the current be turned on, there will be no result save slight smell of escaping chlorine gas. The passage of the current will have certainly split up the salt water according to the above equation, but as the products would be in juxtaposition they would immediately reunite, and the electrical energy would have been spent without any beneficial result having been obtained. Therefore, the all-important problem in designing an electrolytic chlorine cell is the finding of some effective means of isolating from each other the chlorine and caustic: soda as soon as liberated from the...

Jan 1, 1911

By J J. Jiang, M Reimnitz

The Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston Open Pit is mining through a dense network of disused level workings and open stopes of greatly varying sizes. The condition of the stope crowns and remnants is often unknown, and ultimately these structures become a significant proportion of the production floor and pit walls. Significant seismic events and occasionally rock bursts often occur in the underground workings. Seismicity is becoming an issue to the viability of the KCGM Fimiston operations. KCGM needs to take a leading role in understanding mine-induced and regional seismicity. The seismic system trials were initiated in the Fimiston Open Pit in 1996 using the ISS system. The initial system included two triaxial geophone arrays and two triaxial accelerometer arrays installed into two boreholes. The main objectives of the trial were to investigate the suitability of the two types of sensors and the detectability of seismicity in the pit. The trial was regarded as a success and the system has been expanded and improved. The current system consists of 12 triaxial geophone and accelerometer arrays and nine uniaxial geophones. The 12 triaxial arrays are installed in nine boreholes drilled from the pit and the nine uniaxial geophones are installed from underground level workings about 660 m below the original surface elevation. The system is designed to provide seismicity coverage for the entire pit area that is about 2.7 kilometres long, 1.5 kilometres wide and about 300 metres deep. The accuracy of the source location has always been a challenge due to the existence of the dense concentration of stopes and lack of the sensors. It is uncommon to have direct ray path for the seismic waves to propagate to the sensors across the strike, hence sensors have been located along strike and under the old workings. This paper discusses some of the challenges associated with seismic monitoring near mine remnants and seismically active faults. The results of the seismic monitoring are presented, and contrasted to results of three dimensional boundary element numerical modelling. The impact of the seismicity upon pit slope stability is briefly discussed.

Jan 1, 2003

By P Benjamin, H Bohannan, C Farr

Geoffrey Blainey's historical account of the mining activity on the west coast of Tasmania, æThe Peaks of LyellÆ documents the changes over 130 years of activity in the region. Commissioned by the Mount Lyell Mining and Railway Company, emphasis is placed upon the development of the Mount Lyell Mine in Queenstown. Chapter 19 æWidening HorizonsÆ details the review the Mount Lyell Company undertook in 1904/05 to ensure the future of the operation, following the pessimistic outlook regarding diminishing reserves and poor grade ore. The analogies documented between the Mount Lyell Company at that time, and Gold Mines of Australia 90 years on are remarkable, with both companies demonstrating a commitment to the Mount Lyell area through active exploration, the proactive search for alternative technology and the recognition of the valuable human resource. As Blainey writes (Blainey, 1993), æwith its expanding chemical works, its huge Tasmanian mines, its railways and smelter, its coke works and its mine crusade, Mount Lyell was probably one of the nation's five great industrial companies in 1906 or 1907. This brief phase of industrial and mining expansion had its seed in the threat of extinction . . .Æ After a number of reprieves, the Mount Lyell mine did stop production in 1994, but that only provided an impetus for a review and rebirth.

Jan 1, 1998

By T Mizuta, H Satoh, M Ogasawara, M Miyata, M Fukuyama

The Miocene Chichibu granitoids associated with the Chichibu skarn deposit are divided into North Body, South Body and Daikoku altered stock. Orebodies of the Chichibu skarn deposit are mainly distributed in the north-western part of the North Body and Daikoku altered stock. The North Body consists of magnetite-series granitoids ranging from tonalite to granodiorite and to monzogranite from the margins to the centre of the intrusion. The South Body consists of tonalite and granodiorite, and most of these rocks are also classified as magnetite-series granitoids. The Daikoku altered stock consists of a quartz diorite porphyry. The SiO2 contents of the granitic rocks of the North Body and South Body range from 61.6 to 70.7 wt per cent. During magmatic differentiation, Cu, As and Zn contents in fresh granitic rocks of the North Body and South Body increase with SiO2 content up to 63 wt per cent SiO2, and then progressively decrease with increasing SiO2 contents as SiO2 exceeds 65 wt per cent. Estimated pressure for the emplacement of the granitoids is about 0.5 kbars. Cathodoluminescence studies on quartz from those granitic rocks show that vapour rich two-phase fluid inclusions tend to occur in the core of quartz crystals, while halite-bearing poly-phase fluid inclusions occur in the margins of quartz crystals. The distribution of fluid inclusions suggests that fluid composition changed from low to high salinities during the growth of magmatic quartz crystals. Texture showing quartz crystals with an oval shape enclosed by radial aggregates of a mixture of fine-grained quartz, plagioclase and K-feldspar composing the groundmass of the monzogranite also suggests a pressure decrease during solidification of North Body. These findings show that high salinity fluids were present during magmatic differentiation and that Fe-Cu-Pb-Zn-Au-Ag skarn mineralisation of the Chichibu deposit was possibly associated with these high salinity fluids. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

By T Davis

The 500 orebody in the upper levels of Mt Isa Mines in north-west Queensland was mined by sublevel caving and block caving from 1962 to 1969. The hot and reactive rock mass of this orebody provided significant mining challenges including ground temperatures above those resulting from the geothermal gradient. Recently Xstrata Copper has been studying the potential to mine this orebody by modern caving techniques. Part of the study process has included re-accessing the ore zones for diamond drilling and trial development. A cross-cut trial drive, the first primary development into the orebody in more than 30 years, encountered a temperature increase in development holes from low sixties to almost 80¦C in less than 10 m advance. The issues associated with managing this risk include sourcing suitable quantities of reactive ground explosives for a single small heading and the temperature limitations of the explosives and detonators. Risk management outcomes included controls to mitigate the safety and reliability risks relating to misfires. The control that dealt directly with the challenge of continuing development in elevated temperature ground was to cool the holes before and during charging. The most effective and practical cooling medium proved to be water. Rapid rock temperature recharge time meant cooling had to continue as close to firing as possible. Reticulation systems were constructed to allow cooling to take place up until withdrawal for firing. No misfires occurred with the cooling system and additional controls in place. This proved that developing safely and effectively in the elevated ground temperatures of the 500 orebody is practicable.

Jan 1, 2008

By G A. Partington

Recent research has highlighted the potential of a relatively new style of gold mineralisation related to granite intrusion. New discoveries in Alaska, Central Europe and Asia and Eastern Australia with total resources of 1600 t Au offer attractive targets for regional exploration in areas which may have been overlooked in the past. A spatial information system was developed to target granite-gold systems in eastern Australia and the West coast of New Zealand, using well constrained geological and exploration models derived from current research. Target areas were recognised in Queensland, New South Wales, Victoria, Tasmania and on the West Coast of the South Island of New Zealand that have similar spatial data relationships to known granite gold mineralisation elsewhere in the world. The second phase of the modelling better constrained the regional scale target areas by including more detailed geological, geochemical and geophysical data in the GIS to develop prospect-scale targets and to allow the acquisition of tenements over these areas. A geological review of each target area was carried out in the field to put the GIS models into context. The fieldwork has highlighted the potential for this style of mineralisation in New Zealand and will increase investment in mineral exploration and development in New Zealand in the near future.

Jan 1, 2005

By Chung S

The problems associated with equating calculated and measured properties of explosives with blast results are examined. The results from six full-scale test blasts in a limestone quarry are described. The purpose of the full-scale trial was two-fold, i) assess the role of varying aluminum levels (10% maximum) in a given explosive in terms of blasting performance, and, ii) find correlation between calculated, as well as measured properties of explosives and the resulting blasting performance. Each blast consisted of 36 holes, initiated with short period detonators in a staggered 3-row 2.4 m x 2.7 m (burden x spacing) pattern. Each 75 mm diameter borehole with no subgrade contained on the average 22 kg of 65 mm diameter cartridged explosive. The bench height was 6.3 m, with an average collpr of 1.2 m. The calculated and mgasured properties of explosive included, strength, detonation and explosion pressure, VOD, plate-dent depth, underwater bubble and shock energy, and the total energy efficiency. Each blast was instrumented to measure detonation velocity, initiation sequence, muck pile motion by means of high-speed photography and blasting vibrations. The post-blast measurements included photogrammetric survey of muck pile for size distribution on surface, muck pile profile, as well as the extent of backbreak. The results showed that the overall blasting performance of the explosive in question was nearly commensurate with the level of aluminum in the explosive, and there was excellent correlation between the underwater test properties and the blast results. The study also exemplified the need for more extensive post-blast analysis than is usual practice, for quantitative assessment of blasting performance of explosives and providing the necessary data-base for calibration of blasting models.

Jan 1, 1990

By B Chappell

Backfill in the form of mine waste tailings has inherent problems associated with attaining adequate strengths upon placement. Fines are usually removed to ensure adequate drainage, which lowers the cohesive strength of the fill, leaving the fines to be placed in a tailings dam. Electro-drainage and electro-chemical grouting is examined to investigate its effects on densification and shear strength within a silty clay tailing having low permeability and shear strength. Two separate grouting mechanisms are observed for the iron and silica grouts used. Electroosmosis is associated with iron grout that deposits within the tailing matrix under a converging pH gradient, and increases the permeability of the tailing. This process initiates cation exchange and causes cementing of the granular contact points between the clays. Electro-phoresis causes sodium silicate solution to deposit silica grout in the voids of the tailings. The resultant effect of these mechanisms results in an increase in cohesion, leaving the void ratio of the iron grouted tailings as it was but significantly reducing the void ratio of the silica grouted tailings.

Jan 1, 1998

By Bulters J, Sheppard I

Two blasthole density logging programmes have been conducted on the Mt Whaleback iron ore mine to evaluate the use of this type of logging as an aid to blast pattern design. The first programme also involved the setting up of a Density Test facility with which to calibrate the density probe. The programmes indicated that about 22-23 blastholes can be consistently logged per day at a cost of $1.30 per metre. Even though this is only half the rate required to log the average number of blastholes drilled daily on Mt Whaleback, testwork indicated that no significant loss of accuracy results if only half the holes in a pattern are logged. The major results of the programmes were: 1. The density range for black pyritic Shale is 2.2-2,9 g/cc. 2. The density range for soft to medium hard BIF is 2.1-3.0 g/cc. 3. The density range for hard BIF is 3.0-3.6 g/cc. 4. The front row blastholes show consistently lower densities than the main body holes due to blast damage. 5. A low density zone extending to a maximum depth of 6 m occurs at the top of most blastholes and results from blast damage from the bench above. These density results have been used to implement savings in drilling and blasting via pattern expansion and charge optimisation of blastholes. Eight ore

Jan 1, 1986

By T Klinge, P Field, N Sugden, D Trenberth

Mining remains one of the key industries in Australia and many other countries with mineral wealth. In Australia, mining contributes 8.8 per cent to the countryÆs gross domestic product (McKay et al, 2000). In Queensland alone, mineral and petroleum industries contribute approximately $9.4 billion to the StatesÆ gross state product (2001/02) (Young, 2003). Increasing pressure on mining companies to perform in a global marketing environment requires mine management to consider more innovative ways to manage their resources û human, plant and equipment û which includes the gathering and analysis of operations data and information for improved decision making. For any mining operation utilising rubber tyred equipment such as trucks, front-end loaders and ancillary equipment, annual expenditure on tyres and related items can be significant. Even a small reduction in tyre operating costs can have a real effect on the business bottom line performance in the short term. Tyre Application Risk Management (TYREARMÖ) can provide substantial benefits in the long term across a number of KPIs not just through reduction in direct tyre expenditure but through flow-on improvements in safety, productivity and reduced environmental impacts. Several accidents involving tyres have also highlighted an increased need to consider the hazards and resultant risks arising from operations of rubber tyred mining fleets (Torlach and Johnston, 1990). This paper presents the process and results of achieving sustained safety and business improvement through the strategic alliance between an earthmover tyre management service provider, Klinge and Co (Klinge) and a BHP Billiton coal mine. The accompanying case study demonstrates in some detail the overall methodology, and the tools and technologies used where active management of data, its analysis and decisions taken have resulted in a 43 per cent improvement in tyre cost performance and a corresponding reduction in tyre-related downtime since the beginning of the alliance.

Jan 1, 2003

Industry can achieve best results via thorough planning, consultatiion with agencies and local communities and a 'hands on' approach to' environmental problem solvingThe Department of Energy and Minerals, through its Minerals Group, has regulatory responsibility for the mining and extractive industries in Victoria. The role of the group is to facilitate the environmentally responsible development of these industries for the benefit of Victorians. It has a wide range of contacts with other government agencies, local government and community groups.The paper is in three parts; firstly, an overview of the nature and contribution of the mining and extractive industries in Victoria; secondly, the industries' regulatory framework; and thirdly, the environmental issues facing the industries and the management of these issues.

Jan 1, 1992

By W L. Lane, T R. Yanske

The Doe Run Company and its predecessors have been mining for over 130 years utilising the room and pillar mining method. This method has left approximately 20 per cent of the orebody in the remaining pillars. The original design and planning for the mines did not include extensive pillar extraction. This paper summarises the introduction of the pillar extraction and backfill techniques which have been implemented since 1991. These techniques include the use of low cost fill walls up to 20 m in height and the use of slinger trucks for topping off the fill. In conjunction with these accomplishments, much experience and confidence has been gained in the use of numerical modelling as a method of predicting pillar stability as the mining of pillars progresses. These advances have led to pillar extraction becoming a major portion of the overall production and have added to the mine life of Doe RunÆs six operating mines.

Jan 1, 1998

The working of alluvial deposits has from all times been a popular form of mining, not only from the simplieity of its operations, but also, in its more primitive stages, from the possibility of carrying it on without large capital, without skilled lahour, expensive plant, long terms of preparatory work, or, in fact, any other requisite than a shovel, a dish, and a stout pair of arms. It is possibly one of the oldest industries, and probably, also, it has been one of the most profitable.In tbe Australian States the happy days of rid alluvial deposits, when gold was to be hltd for the shovelling, are now almost over. The lust for gold has caused almost every corner of the world to be ransacked, and the more easily earned wealth to he exhausted: for the most part there remain now those deposits only which are too poor to be profitably worked by means of the implements and methods of old times. But, though the deposits have become poorer, the keen inventiveness of man has devised means whereby such large quantIties can be treated at a cost so low that he can still make a profit out of them. In this article, out of the many means devised, three only will be referred to-viz., hydraulic sluicing, bucket dredging, and hydraulic dredging. All mining may be divided into three principal operations-1st, the breaking down and conveying of the ground to where it is to be treated for the recovery of the metallic values, 2nd, the treatment of the material for the recovery of those values; and, 3rd) the removal of the worthless material or tailings. In all mining the object is to effect these three processes for the least expenditure of money commensurate with the highest degree of efficiency.

Jan 1, 1907

Vaal Reefs Mine annually produces some 75 tonnes of gold. Stoping operations, using a scattered mining method, are conducted on several reef horizons within Witwatersrand Supergroup metasediments of the Klerksdorp Goldfield. Current grades average 7.19 g/t Au over a 133cm stoping width. The reef horizons, of which the Vaal Reef is the most important, consists of 2.9Ga palaeoplacer deposits at the base of low angle unconformities. Typically, a reef comprises a mature quartz and chert conglomerate with a siliceous matrix and intergranular pyrite and carbon. Geologists are primarily responsible for underground mapping and supervising of drilling programs. To a lesser extent they are involved with sampling, grade control, ore reserve estimation, mine planning and rock mechanics. Due to a general decline in grades of gold mines, an escalation of production costs, and with the current weak gold price, it has become essential to improve production efficiencies. Consequently the role of the mine geologist has moved away from that of simply keeping the mining people "on reef'. Greater emphasis is being placed on refining geological models to assist in selective mining of the reef and investigations of secondary reef horizons are encouraged. Exploration within fault losses and re-evaluation of pillars is important, and geologists are becoming more involved with sampling and grade control exercises.

Jan 1, 1990

By H J. J Boshoff, A J. Karrasch

Mine planners frequently face the challenge of mitigating the impact of climatic events on mining operations, such as floods and droughts. Specific water management infrastructure can be implemented to meet operational requirements in response to these events. However, the effect of flood protection, for instance, may reduce the resilience of the site to drought. The probability and duration of unfavourable climate sequences significantly influences the net present value (NPV) of implementing specific water management infrastructure.Good life-of-mine planning will consider the incremental development of the project, and provide staged development plans. Water management infrastructure and the timing of implementation are facets of this process.CITATION:Boshoff, H J J and Karrasch, A J, 2016. A decision-making framework for water supply and flood protection options in net present value terms, in Proceedings Life-of-Mine 2016 Conference , pp 196–199 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016