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By H Höft

Today tunnel segment liners are sealed with corner-vulcanised gaskets made of extruded elastomeric compression profiles. The profile geometries and the elastomeric materials have been further developed in course of time to meet the steadily increasing water-proofing requirements. After 40 years of using such compression gaskets, a wide range of proven standard profile geometries and well-known brands can be found on the market. Even so, there is still potential for further developments and improvement, not only with regard to the water-proofing performance. Permanently increasing cost pressure in the segment production plants demands further developments and new solutions with regard to application techniques. This is an abstract only. No paper was prepared for this abstract.

Mar 8, 2011

By Huber A. L

Research and development into alternate gold and precious metals adsorbents has resulted in the development of a new technology named the AUROSAVE adsorption process (ARGOSAVE'" for high silver con- tent ores). Adsorbents called VITROKELE'" can be tailored for either Gold I (cyanide leach) or Gold III (halide leach) applications. VITROKELE consists of a chemically synthetic adsorbent carried on an inert substrate, often a polystyrene bead. It is suitable for both in- pulp and in-solution use. VITROKELE adsorbent offers certain advan- tages over both carbon and ion exchange resin adsorbents. This paper describes testwork on Australian ores and commercial solu- tions obtained from operating Australian plants demonstrating the kinetic loading characteristics, elution methods and other operating parameters of VITROKELE adsorbent in the cyanide system. Brief reference is made to VITROKELE in the Gold III system.

Jan 1, 1988

By Battino S

ABSTRACT' The high gas emissions associated with coal extraction at some-Australian collieries have provided a need to investigate the methods used to predict these gas levels and the vent- ilation requirements for gas dilution. It is generally accepted that the introduction of longwall extraction in particular is associated with complex ventilation planning problems. These problems are made much more severe when the colliery introducing longwalls is already facing high gas emissions even during the development stages. A forecast of likely gas emissions during the longwall mining process indicated possible ventilation problems in maintaining the necessary ventilation levels to satisfy the statutory gas limitations for various production rates. Although there are sound principles used in world recognised methods of gas emission prediction a new approach developed from the findings of the Barbara Experimental Mine in Poland appears most suitable for Australian conditions. This has been applied to an Australian colliery preparing for longwall mining using statistical methods for air

Jan 1, 1983

By Richmond AJ, Allan J

The use of long-hole in-seam drilling techniques for seam gas drainage ahead of mining was introduced to the Australian coal industry by ACIRL in mid-1981. ACIRL's research program has involved the development and demonstration of drilling and borehole survey technology in addition to evaluating the gas drainage potential of long-hole in- seam boreholes. This paper presents the results of the long-hole drilling carried out to date in the Illawarra District of the New South Wales coal fields. Drilling experience in relation to both vertical and horizontal directional control of the drill string, drill performance and borehole survey techniques are discussed. In addition, results of gas drainage effected by the long boreholes are presented. Future potential and requirements for further development of this technology are Reviewed.

Jan 1, 1982

By R Polmear, G Mauger

You wouldnÆt start excavating before testing core samples, so why would you approve a project plan before all factors have been identified, reviewed and addressed? Even a champion sports team made up of the best players canÆt produce optimal results without a well understood and agreed game plan. Could an F1 racing team produce their outstanding performance without rigorous evaluation and testing of the factors for successful performance? Why would we expect a capital works project team to be able to get it right without an understanding and an involvement in setting and implementing the overall game plan and without an understanding of all stakeholder requirements? For International PowerÆs Hazelwood (IPRH) mine in Victoria, the challenge was development and delivery of a 40 year mine plan, ultimately involving relocation of existing mine operations into an adjacent new coal field, land acquisitions and major environmental and other approvals to allow diversion of three streams, a highway, an Over Dimension route and other infrastructure in a political and environmentally sensitive atmosphere. The lessons from International Power HazelwoodÆs (IPRH) experience are: that the clear set of project principles and guiding values ensured delivery of a robust plan; a robust plan can withstand significant change; and value management (VM) played an important role in providing assurance, to all, that the plan was sound at both the strategic and micro levels. This Hazelwood mine project included five major VM workshops. The first was a critical review process in addition to design and cost reviews. This VM workshop was used to analyse, at a high level, the preferred coal mining sequence and design concepts, together with the interaction between design elements, risks and costs. In addition to this, the workshop provided an agreed common pathway for all downstream decisions. A second VM study was conducted to ensure that the proposed plan and design for relocation of the conveying systems from the existing mine into the new field were planned for optimum achievement from a whole of life cost, time, operational and maintenance perspective, plus the logistics of continuing operations while relocating assets. A third study followed to review the Conveyor Transfer Alliance and review functional design. A fourth VM study workshop was formed at the start of Phase 2 Alliance to ensure that the best value for money was being achieved through the current design, schedule and project arrangements and that all interfaces between parties had been reviewed and responsibilities were clear and understood. Other studies are outlined later in this paper. This paper details the evaluation criteria and processes used in the project evaluation that led to the WestField Mine Development.

Jan 1, 2007

By Chitombo GPF

The dilution of blasted ore with cemented backfill materials has been recognised as a significant factor influencing the economics of some underground metalliferous mining operations. Several mechanisms have heen identified as possible causes of fill failures. The purpose of this study was to determine the possibility of damage as the result of one mechanism, that of production blasting adjacent to bodies of cemented hydraulic fill (CHF). A vibration amplitude transfer function has been developed to model the transmission of blast vibrations from the source, through ore, across the ore to CHF interface and into the CHF mass. The model may be applied in the near field. The model has permitted estimation of vibration amplitude at a point in a CHF mass, to which damage criteria may be applied. A number of assumptions and simplifications have been made to render the problem relatively tractable. Ore and CHF material characteristics recorded by a number of authors were utilised to formulate preliminary damage estimations. A simple application of the amplitude transfer model indicated that a zone of plastically deformed CHF would be produced, and would extend to a distance of approximately 0.5 metres from the interface into the CHF. A sensitivity analysis was also conducted, that indicated that the zone of plastic deformation would be more extensive given appropriate conditions. Recommendations for further model development and future laboratory and field investigations have been made.

Jan 1, 1998

Intermontane valleys form unusual features of compressive mountain belts both in the sharp topographic break they represent and in the strike-slip displacements often associated with the valleys. Such strike-slip motion seems hard to reconcile in the actively deforming Andes where reconstructions have indicated nearly perpendicular Cenozoic plate convergence. Detailed study of a part of the Argentine Andes between latitude 31-33¦S suggests that, although strike-slip displacements may have largely created a prominent intermontane valley system, no Holocene strike-slip displacements are observed amid the relatively active compressional deformation along the mountain belt flanks. New plate reconstructions, treating the Nazca plate as two microplates separated by fractures along the Nazca Ridge, predict large components of strike-slip motion between the South American and Nazca Plates for the period from 10 to 5 Ma. These reconstructed plate motions are consistent with strains derived from recent kinematic analyses of minor faults along the southeast margin of the Puna plateau and the general timing of tectonic phases in the Andes.

Jan 1, 1987

By M I. Pownceby, M A. Rhamdhani, S Purohit, G Brooks

The current practice of magnetite ore agglomeration involves high temperature oxidation roasting (typically at 1200–1350°C) of magnetite to hematite phase in order to improve the strength and reducibility of pellets. The requirement to pre-oxidise the magnetite before introduction to an ironmaking plant increases the CO2 emissions generated during the ironmaking process. In our previous papers, a novel, alternative agglomeration route for magnetite ores was presented where magnetite was converted to a reducible CaFe3O5 (CWF) phase through the addition of lime to produce a Lime-Magnetite Pellet (LMP) feedstock that can be directly charged to ironmaking units. The LMP process eliminates the magnetite oxidation stage, thereby reducing the CO2 emission during ironmaking. The concept was tested by thermodynamic calculations, high temperature experiments and scaled-down pilot scale test work. In this paper, larger scale synthesis of halfstoichiometric LMPs (1 mole of Fe3O4 and ½ mole of CaCO3) were prepared using a balling drum, followed by overnight drying at 110°C and induration at 1050°C for two hours. The LMPs were analysed using X-Ray Diffraction and Scanning Electron Microscope techniques for phase and microstructure characterisation. The LMPs were found to have 14–15 wt. per cent of CWF phase when indurated under a CO2/CO ratio of 8.5:1. Pilot scale testing of the LMPs was conducted following ISO standard test procedures. The test results indicated the LMP’s had a Reducibility Index (RI) of over 91 per cent, a Tumbler Index (TI) of 87 per cent and a Reduction Degradation Index (RDI) of 4.6 per cent. The results indicate LMPs may be useful as an alternative feedstock to ironmaking processes that would result in lower overall CO2 emissions.

Nov 8, 2021

By A Lechner, T Baumgartl, S Arnold, P Audet

When revegetation is a part of a rehabilitation strategy at mine sites in arid and semi-arid environments, its success can be strongly affected by the availability of water prior or during the time of seed dormancy, germination and early growth of seedlings. The semi-arid and arid environments of northern Australia are characterised by highly variable and erratic rainfall and hence the actual weather conditions at and around the time of germination and seedling emergence play a critical role in determining the success of plant establishment and the type of plant community that may develop.Using available climate data, an analysis has been undertaken and a set of indices has been developed which describe the suitability of the climatic conditions for rehabilitation. In total, eight sites from Queensland and one site from New South Wales, Australia have been analysed. It could be determined that regular rainfall and relatively short periods of water-deficit are key characteristics of climate suitability. A comparison of the locations studied allowed the separation into suitable and susceptible locations in terms of the availability of water, amount of rain and duration of drought between rain events.In our experience, specific estimates of climate suitability are rarely incorporated into the design of mined land rehabilitation programs. We consider that the regional intensity, seasonality and extremity of climate represent an overarching component of landscape complexity, which in turn will influence the development of post-disturbance ecosystems in these regions. This paper presents the outcome of climate analyses paired with the development of suitability indices. A conceptual framework is presented explaining the suitability matrix and its incorporation as a prognosis tool to achieve greater certainty for success in rehabilitation development.CITATION:Baumgartl, T, Arnold, S, Audet, P and Lechner, A, 2014. Development of climate-based suitability indices for the improvement of success in rehabilitation, in Proceedings Life-of-Mine 2014 , pp 483–490 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

The current quantity of rejects from coal beneficiation in Australia represents 20 to 25% of raw black coal production. Approximately 80% of the rejects are derived from coarse processing for particles in the 200mm to 0.5mm size range. The safe and enviornmentally acceptable storage of coarse coal rejects is of interest to coal mining companies. Additional public benefit would be derived from the utilisation of a waste product as a source of fill material for civil and mining engineering applications. BHP Engineering has taken a leading role in the design for storage and utilisation of coarse rejects from two mines associated with the Broken Hill Proprietary Conipany Ltd. The tailings dam at Stockton Borehole Colliery (N.S.W.) is to be raised and a study by BHP Engineering has shown that coarse rejects are suitable for the formation of the supporting embankment surrounding a compacted clay core. Transportation and storage of coarse rejects at the Thiess Dampier Mitsui Riverside Mine (Moranbah, Qld) is achieved by a conveyor leading directly from the coal preparation plant to a discharge stacker on the crest of the rejects stockpile. Production of coarse rejects was higher than anticipated for the initial dump design. BHP Engineering has completed a review of dump design with emphasis on safe operating conditions for the conveyors and stacker system. Data on the geotechnical properties of coarse rejects from Australian coal mines are presented. Coarse coal rejects are a material which should not be considered as waste, but as a potentially valuable resource for many future applications. Appropriate engineering design for the storage and utilisation of coarse rejects would result in an improved environment and economic benefits for the Community.

Jan 1, 1987

By G Diprose

Diamond exploration in Queensland is influenced by the South African approach modified by the discovery of diamonds in Lamproite in Western Australia. The current approach is to explore for Kimberlite and Lamproite bodies using indicator minerals dispersed by fluvial and colluvial processes. In the north-west, diamonds are derived from kimberlitic and lamproitic sources, whereas those in the coastal and subcoastal areas of eastern Queensland are associated with xenoliths included in rocks formed during Cainozoic volcanism. In these areas, sapphire is commonly associated with diamonds. In New South Wales diamonds in economic quantities occur in alkali basaltic intrusions and a subduction model has been proposed for these occurrences (Barrows et al, 1996). Exploration for diamonds in Australia increased following the discovery and exploitation of the Argyle mine. State geological surveys have produced digital information on the local occurrences of diamonds. As part of the Smart Mining Initiative (2006 - 2010), the Geological Survey of Queensland compiled a database and report on microdiamonds and diamond indicator minerals from open file company exploration data from 1968 to 2008 from the Department of Mines and EnergyÆs QDEX system. Most exploration in Queensland was conducted with exploration for other commodities. There is no commercial exploitation of diamonds in Queensland and, to date, only rare occurrences of microdiamonds. There is a regional difference in diamond occurrences with the kimberlitic and lamproitic models favoured for the north-western regions of the State and the subduction (S-type model) favoured for the eastern coastal zone linked to Cainozoic alkalic basaltic volcanism. Further diamond exploration is warranted in Cainozoic basalt provinces along the eastern coastal and near coastal regions and in the north-west of the state in conjunction with airborne geophysics flown as part of current Departmental Smart initiatives. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

INCREASE OF THE OIL CONSUMPTIONIt is of the greatest interest to study the prospects open today for the petroleum industry by looking back to the past years.The' results for the past 15,years can be said. to be- satisfying; - the develop-ment of the petroleum industry has sustained a very fast tempo and the world consumption of energy has around the years 1960-1961 - reached aòpeak figure.Undoubtedly, the petroleum industry is the principal beneficiary of the growth of world, energy demand. For the caning years a slackening of the rate of expansion is'. likely to be expected; but will. not alter the general trend. This ' slackening of expansion may be explained, partly by a better use of the energy consumed and by the increased use of new types of energy, mainly natural gas.Although.the development of world energy demands follow structural and tech-nical modifications".,-At. can be foreseen, without any doubt, that the petroleum products. consumption. vri 11 be less affected than any other type of energy by this limited reduction in the rate of increase.

Jan 1, 1962

By I Gray

This paper examines the effects of the changes in stress that a coal may undergo as part of the drainage process. As a consequence of this, some coal seams will come to the situation that they have zero horizontal stress existing within them at the time of mining. The hypothesis of this paper is that this lack of horizontal confining stress means that on mining, the vertical stresses may be easily raised to a level where failure occurs. This failure may be accompanied by significant energy release from energy stored within the coal as well as that coming from the roof and floor. To determine the state of stress within the coal seam, the concept of the effective stress path that the coal passes through is examined and is found to be very dependent on the shrinkage of the coal with degassing, the Young’s modulus of the coal and its Poisson’s ratio. The Young’s modulus of the coal is important and has been found to be highly dependent on the state of stress within the coal. It may change by more than an order of magnitude.CITATION:Gray, I, 2014. The consequences for pillar stability of zero confining stress brought about by forced or natural drainage, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 331–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By P Hawkes

Within the mining industry computers have made their most significant impact with 3D design, visualisation and resource modelling/ optimisation. Recently, the application of computers to data gathering and accounting functions has also started to reap benefits. These two areas of application cover the beginning and end of the mining process. There has been limited use of computers on the middle section, the actual mining process. This is interesting when considering the relative proportion of overall mining costs that this section produces. There is a certain amount of irony in the lack of mining application software for developing accurate budgets compared to the systems/software then used to review performance against budget. Computers have been used extensively in the manufacturing industry to design, model and simulate the manufacturing process. This has not been extended to the mining process. But, we all strive to have an open pit that replicates a manufacturing plant û smooth, efficient, optimal production. If we could model mining operations with the confidence of plastic box makers we would reduce risk by an order of magnitude, improve planning and focus on value drivers. Cost û benefit analysis would be easy. The extrapolation of manufacturing to mining process models is difficult. The variables in the manufacturing process are fewer in number, have low volatility and are highly predictable. The time between a box falling on a conveyor belt and falling off is very consistent. Mining is quite the opposite. It has large numbers of variables, some of which are unpredictable and volatile. The time to fill an excavator bucket could vary by 30 per cent and the frequency distribution is unlikely to be a mathematically simple normal distribution. Further, each of these variables can be distorted by one-another û they are interrelated. The mining process is a disjointed flow of parcels whereas manufacturing is a controlled continuous feed. A loaded truck might join a ramp and follow a slow water cart up. This is the equivalent of a localised voltage drop on equipment in a manufacturing plant. The manufacturing plant is quite likely to rapidly recover to full capacity. Whereas the slow truck might throw the mining fleet cycle out of balance for hours û trucks queuing at the ROM bin and so on. A mining process simulation has been created that addresses these mining variable issues to produce a highly accurate model of the open pit mining process. The number of uses for such a model is growing rapidly as it is being utilised for a variety of projects within the industry. This paper discusses the need for and application of mining process models.

Jan 1, 2003

By Brady B. H

Increasingly, consideration is being given to the nominal `outcomes' of degree courses in engineering, including mining engineering. These are concerned not only with knowledge and technical understanding but also with capabilities in the professional application of engineering principles to problem solving, multi-disciplinary teamwork, communication and life-long learning. This paper discusses concepts of education, professional formation and training and the associated development of competencies in applying knowledge, understanding and technical insights and skills to new situations. In developing guidelines on preferred attributes and competencies in graduate mining engineers, a survey was conducted of a range of industry personnel involved in selecting graduate mining engineers. The results not only clarified the spectrum of competencies sought but also provided valuable detailed views to assist in defining a mining engineering curriculum. Considering a greater concern with the development of more `well-rounded' graduates, the implications are discussed with regard to teaching and assessment activities and the time demands on academic staff when a `coaching' role is emphasised. In line with international and Australian moves in engineering education, notions on education of mining engineering graduates in Australia are under review. The results will provide continuing challenges to all involved.

Jan 1, 1997

By J Lane, D J. Barker, B Pei

Queensland Alumina Limited (QAL) is the worldÆs largest producer of smelter grade alumina, located in Gladstone, Queensland, Australia. The plant employs evaporative cooling towers for waste heat rejection. Process water requirements include red mud residue disposal, steam venting to the atmosphere and Calcination feed moisture. Raw (untreated) water consumption in 2001 was 37 700 m3/d or 3.8 m3 per tonne of production. The Gladstone region experienced a water shortage in the period 2001 to 2003, resulting in progressive water restrictions. Industry operated under a ten per cent restriction from April 2002 and in November 2002 a 25 per cent restriction came in force. The maximum restriction level of 50 per cent was anticipated for the middle of 2003. Water restrictions of these magnitudes have the potential to result in significant production limitations, which would have major economic consequences for QALÆs owners, customers, suppliers and employees. Therefore it was imperative that measures be found to mitigate the impact of these restrictions. Furthermore, as one of the largest water users in the Gladstone region, QAL had an obligation to the community to minimise water usage as much as possible. A thorough analysis of water usage on site was conducted, focussing on all water streams leaving the plant. The philosophy used was that by minimising water outputs, the inputs would follow suit. Where possible, preference was given to solutions that provided lasting water savings. This occurs when the value of the water saving justifies the project cost, irrespective of water restrictions. By June 2002 an average water saving of 19 per cent was achieved, almost double the required saving. By end November 2002 further projects had increased the total water saving to 29 per cent, mainly through the re-use of GladstoneÆs municipal treated effluent as wash water. Further measures to reach the target of 50 per cent reduction were investigated. The evaporative cooling system was to be replaced with seawater cooling, using cooling towers to minimise the seawater pumping cost. Another benefit of this concept was the ability to dispose of the cooling tower bleed stream with the existing system for neutralised red mud disposal. This would avoid the need for an additional environmental outfall from the plant. In February 2003 the Gladstone region received over 500 mm of rain, which boosted water reserves to five years supply at forecast usage rates. This led to the lifting of all water restriction. As most of the implemented water savings measures are economically viable in the absence of water restrictions, raw water usage at QAL is still less than 75 per cent of pre-2002 levels.

Jan 1, 2003

The Writer's knowledge of this region began in 1912, while he was with the Geological Survey of South Australia, and, investigated the principles governing the occurrence of fresh and saline ground waters in the area then being opened for closer settlement by the railways under construction from Port Lincoln.These field investigatons for water were extensive rather than intensive, but other examinations covered certain mineral aspects. The Writer also has' had the benefit in the preparation of this paper, of later work done by others, as well as of the monumental earlier work in South Australia by the late H. Y. L. Brown.AREAThe area dealt with, approximately 21,000 square miles, lies to the south of the latitude of Port Augusta.TOPOGRAPHYAs a whole the region is one of low relief, but the Olinthus Range, west of Cowell and north of Cleve, reaches an elevation of 2,000ft., while there is als0 a high area west of Port Lincoln and Tumby Bay. At the north end of the region the Gawler Ranges are formed by the dissection of a thick sheet of felspar porphyry extending over two degrees of longitude, by a width of 20 to 70 miles, with fairly uniform maximum elevations of the undissected portions of the order of 1,000 ft. above sea level. South of the Gawler Ranges are many isolated ridges up to 1,000ft. in height, generally sedimentary and trend...

Jan 1, 1951

By A Keddie

Standard microeconomic theory suggests that the behaviour of mineral extraction and processing firms with respect to their demand for water can be modelled and a market demand for water subsequently derived. Such a model, although an abstraction of the real world, should be able to predict the responsiveness of quantity of water demanded to change in price, and, change in demand to a range of factors including: expectations about reliability of supply, changed commodity prices for mineral production, and change in water technology and storage at mine site. This paper demonstrates that the price of water is particularly responsive to changes in demand and that although price increases would result in some additional supplies, physical constraints on supply suggest that the industry will be paying considerably higher prices for water in the future. It is recommended that the mining industry undertakes quantification of possible price increases to position itself to minimise the impact on their operating costs as well as to make responsible capital investment decisions to facilitate future expansion or commissioning of new mines. Substantial investment is required to commission a new mining venture with expected rates of return subject to risk and uncertainty due to fluctuations in world commodity markets as well as reliability of secure supplies of inputs. If a reliable supply of water was subject to uncertainty and water was a critical input for production, then the initial mine design would typically consider a range of production decisions contingent on levels of uncertainty with respect to water supply. These states or sets of water supply, will affect production decisions and future water demand. Modelling production decisions contingent on different states of nature, termed the state-contingent approach, provides a number of insights about producer behaviour under uncertainty. This paper investigates the assumptions underlying the derivation of the market demand for water by the mineral resource industry and identifies the drivers of demand and the responsiveness of the industry to change in price and supply, particularly in relation to capital investment in water-use technologies. The usefulness of these models to the mining industry is considered by reference to the increasing demand for water by the industry in Queensland, in a climate of water shortages.

Jan 1, 2006

By J C. Diaz, C R. Scherpenisse

Blasting represents one of the most relevant unit operations in the process of mineral extraction. The final objective of this operation is that of obtaining an adequate final fragment size distribution such that the combined costs of drilling, blasting, excavation and transport, and crushing/grinding, are minimised, while at the same time producing the minimum possible level of damage to the surrounding rock mass. The strong influence that drilling and blasting has over the subsequent processes involved in the operational cycle makes it imminently desirable to have access to experience and technology which make possible the evaluation and optimisation of this unit operation. The correct use of vibration monitoring techniques offers a number of benefits in terms of their ability to examine any blasting process in detail. In effect, the measurement of particle velocity levels that result from the detonation of each explosive charge offers a means by which it is possible to measure relative efficiency of each charge, interactions (productive and counterproductive) between adjacent charges, and a definitive indication of general performance of any given blast design and its implementation. In this way the monitoring of blast vibrations in rock due to the blast event, can be used as a diagnostic tool, given that the correct interpretation of the vibration traces allows the determination of the level of interaction between the design and operational variables of the blast event. This makes it possible to evaluate, for example, the presence of out of sequence detonations, statistical scatter in the detonation times of pyrotechnic delay detonators, deficient detonation of charges, instantaneous detonation of charges and sympathetic detonation of charges, as well as the general of vibration levels in terms of peak particle velocity, acceleration, and displacement. Another important use of such data is in the construction of a database relating vibration levels to charge weight, hole diameter, and distance, for any given rock type, enables the calibration of predictive vibration models which in turn make it possible to predict the damaging effects of blasting. Knowledge of both the vibration levels induced, combined with quantitative measures of the geomechanical competence of a rock mass make it possible to estimate the probability of producing blast induced damage. The high levels of vibration generated by some blast events may damage the rock mass, producing new fractures or extending and dilating existing fractures. The vibration in this context may be considered as a dynamic stress provoking strain in the rock mass. This paper describes the application of the vibration monitoring technique, particularly in the underground mining environment, and its importance in diagnosis, modelling, control, and optimisation of the development blasting process. The potential of the technique is assessed in the context of achieving substantial techno-economic improvements development blasting results, increasing output whilst minimising the operational costs of the mining process.

Jan 1, 1999

By Blaskett K. S

The physical properties of monazite and the minerals with which it is associated in east coast beach sands are studied and discussed. Possible means for improving recovery are examined. In particular, it is suggested that the practice of splitting the heavy mineral concentrate into two parts as a preliminary to treatment in separate "rutile" and "zircon" mills can be modified in a simple fashion by the addition of an extra magnetic separation stage so as to aid monazite recovery.INTRODUCTIONBeach sand deposits on the east coast of Australia are a major source of rutile and zircon, and supply 80 per cent or more of world requirements. The deposits also contain a small amount of monazite, averaging about 0.5 per cent of the total heavy minerals. Yet despite a steady price in recent years of £150-160 per ton, monazite production has remained relatively small.On the basis of rutiIe production, potential monazite production on the east coast was about 1,500 tons in 1956, but only 102 tons of high-grade concentrate was produced. The main deterrent to increased production has probably been the capital cost of the necessary equipment. Separate electrostatic and magnetic equipment and separate table concentration and drying constitute a considerable outlay for a by-product contributing 4 to 5 per cent of the revenue from rutiIe.It is the purpose of this paper to discuss monazite concentration generally and to suggest modifications to flowsheets, which may facilitate monazite production while maintaining the main objective, simple and cheap means for maximum rutile production.

Jan 1, 1958