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By J Watson, C Zhang, I Canbulat, C Wei

Coal burst is defined as a dynamic release of energy within the rock or coal mass in underground coalmines that causes violent rock or coal ejection in the vicinity of mine excavations. It poses one of the highest safety and productivity risks in the mining industry as coal bursts have the potential to cause multiple fatalities. As Australian coalmines go deeper, the likelihood of coal burst increases. Thus, it is critical to assess the ground support requirements in coal burst-prone conditions. A previous study conducted by the authors (Wei et al, 2022) reviewed the support capacities of a wide range of ground support elements in laboratory tests. This study aims to examine the role and effects of the ground support elements and systems for Australian underground coalmines to minimise the damage caused by catastrophic dynamic failures (ie coal and rock burst) and enhance the safety of mine workers.

Nov 29, 2022

The AJ Parker Cooperative Research Centre for Hydrometallurgy is the focus of a world-class effort in providing technical solutions to the minerals industry. The 85 FTE staff are drawn from the CentreÆs five joint venture research partners comprising universities (Curtin, Murdoch and Qld) and government research agencies (CSIRO and WA Dept of Industry and Resources). There are also 12 industry partners, representing most of the leading mining companies in the world. Around 45 postgraduate students, mainly PhDs, make a significant contribution to the research effort. Total annual expenditure on R&D is around $17 million.Hydrometallurgy activities encompass both fundamental and applied research across the alumina, gold and base metal sectors. The Centre is now growing its client base into overseas markets, particularly North America, South Africa and Europe. Quality, strategic R&D by the Parker Centre is seen by the industry as an attractive investment. A recent survey of the industry revealed an estimated ten-fold return based on direct costs of research to the client. In addition, the Parker Centre has a strong commitment to education of postgraduate students wishing to enter the mining industry as well as providing specialist courses for those technical professionals already employed in the industry. The wide range of employment opportunities in the mining industry is reflected in the diversity of the disciplines amongst the CentreÆs research team, eg extractive metallurgy, chemistry, biotechnology, physics, engineering, molecular modelling, microscopy, geology and computational fluid dynamics. How does an atomic force microscope and molecular modelling improve our ability to control gypsum scaling or understand crystallisation of alumina in a Bayer plant? Can a biologist contribute to the problem of the slow leaching of copper from chalcopyrite? Why are computational fluid dynamics and lasers the basis of understanding how to make thickeners work more efficiently. Can you combine a PhD or Honours degree with industry experience? What is crud and why is nickel stressed? These are typical examples of the CentreÆs research activities and demonstrate the contributions of its multi-disciplinary teams which keep the Australian mining industry at the cutting edge of advanced global technology.

Jan 1, 2003

By Le V, Nguyen Ngoc Quynh, R H. Murfitt

The Truong Son Fold belt in Indochina hosts the significant Sepon gold-copper district (Laos) and the similar gold-basemetal districts of Phuoc Son and Bong Mieu (Vietnam). With over seven years of exploration, Toronto-listed Olympus Pacific Minerals Inc, is one of few foreign companies that have to date made a substantial investment in mineral exploration in Vietnam.Much of this work has been conducted along the Phuoc Son û Tam Ky Suture, on the south-eastern limb of the Truong Son Fold belt on the Vietnamese side of the border with Laos. These programs have produced a significant number of gold prospects at varying stages of exploration development. The Phuoc Son û Tam Ky Suture is a major Paleozoic subduction zone that extends from northern Laos, through Central Vietnam and out into the South China Sea.It represents a Lower Mesozoic collision zone between the Paleozoic-age Truong Son fold-belt terrain to the north, with the crystalline terrain of the Pre-Cambrian Kontum Block to the south. Since its formation, it has been a locus of deep faulting, continental accretion, intensive intrusive activity and mineralisation. This paper briefly discusses the geological setting, structure, metamorphism, mineralisation, exploration history, and proposed mining development of the Olympus Phuoc Son Gold Project, with particular reference to the Phuoc Son û Tam Ky suture.

Jan 1, 2004

By Mostyn G

In the last three decades various theories have been presented to allow the estimation of the force required to cut rock. These have generally relied on an hypothesised mechanism of chip formation.The paper presents results of an experimental program completed on an unjointed artificial rock in which the force and chip geometry were measured during deep cutting with a quarter scale bulldozer tyne. The program included various depths of cut and artificial rock of varying strength. The experimental results are compared with predictions based on three expressions for cutting force. Generally the measured forces are within the range of those predicted but none of the methods predicts the cutting force with any accuracy. It is considered that the discrepancies are due, in part, to the fact the that actual shape of the chip formed in deep cutting is quite different to that assumed in developing the theories and thus the theories cannot be expected to predict the cutting forces. It is concluded that Evans and Nishimatsu's theories predict lower bound estimates of the horizontal cutting forces. Deliac and Fairhurst's approach appears to over estimate the forces required to cut rock. New methods of prediction are required based on the observed mechanisms of failure.

Jan 1, 1993

By Eren H

For a hydrocyclone of fIXed geometry, DC, Di, DO and ? are constants, the variable parameters affecting the performance are Qi, Fi, Du and H. (See Appendix 2 for definition of symbols).The relationship between d50c, Qi, Fi, Du and H gives models which can effectively be used for performance predictions. Such models have already been established by Lynch et al and by Plitt.These models have been tried in a limited manner under continuous operating conditions for on-line cowol. For on-line control effective and accurate instrumentation is required for which a new set up is proposed. Using this set up, a new model was established. A feature in this model is that deviations from the norm of operational parameters affecting d50c were considered. It is shown that these deviations generated by the disturbance of one or more of variations in the parameters, can be monitored by a computer and suitable signals generated to control servo mechanisms for restoring the required d50c value.The logic followed in developing the computer software is described and the application of the model is indicated.

Jan 1, 1990

By Stone AM, Romensky G

The requirement for economic operation of unit trains carrying bulk materials has dictated that rapid and accurate bulk loading methods be provided. The train loading station at Phosphate Hill, built for Queensland Phosphate Ltd. to load rock phosphate, provides this facility and whilst the concept used is not unique, it contains a number of novel features that are considered to advance the "state of the art'' in this field. This paper briefly reviews some alternative concepts evaluated, and describes the design and operation of the scheme ultimately selected as being most appropriate to the project requirements. it is one which utilises a variable speed belt feeder whose speed is controlled in proportion to the weight rate of material moving on the belt as measured against a set point

Jan 1, 1978

By X Li, M-F Zhou

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Yinachang deposit in south-west China contains large amounts of Fe, Cu and rare earth elements (REEs). Apatite in this deposit records complex REE mineralisation and remobilisation processes.Fe-Cu-(REE) mineralisation at Yinachang occurred at ~1700 Ma, and three stages of alteration and mineralisation are identified: Na-(Fe) alteration, Fe-(REE) mineralisation and Cu-(REE) mineralisation. In the Fe-(REE) mineralisation stage, REE-rich apatite formed together with magnetite. In the Cu-(REE) mineralisation stage, fluids undersaturated with REEs interacted with early-formed REE-rich apatite, during which large proportions of REEs, especially light REEs (LREEs), were leached from apatite.At ~840 Ma, apatite experienced a second interaction with fluid. In that process, REEs were removed from the apatite structure but immediately reprecipitated into new phases within the apatite. Thus, numerous REE mineral inclusions including bastnaesite, monazite and minor Y-phosphate occur in the apatite. There are also a very small portion of LREEs that were transported out of the apatite, resulting in the growth of bastnaesite and monazite grains outside the apatite.This study demonstrates that REEs can be mobilised in multistage hydrothermal activities and highlights the significance of fluid compositions for REE transportation and deposition behaviours in hydrothermal systems.CITATION:Li, X and Zhou, M-F, 2015. Hydrothermal rare earth element mobilisation processes in the Yinachang Fe-Cu-(REE) deposit, south-west China, in Proceedings PACRIM 2015 Congress, pp 265–270 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By S MacKinnon, J Kok

Potential areas for improvement in flotation performance were identified during JKTech model development surveys in October 2003. Subsequent implementation of the JKTech recommendations in consultation with flotation cell manufacturer Outokumpu have resulted in gold flotation recovery increases of more than four per cent over a two-year period. One of these recommendations was the installation of High Shear Stators in the Cleaner and Recleaner flotation cells. The High Shear Stator installation project was justified based on simulations completed using JKSimFloat. Bubble size measurements completed before and after installation of High Shear Stators showed a reduction in mean bubble size of approximately 50 per cent in the Cleaner cells. Both Cleaner and Recleaner banks showed a significant narrowing of the bubble size distributions following the installation. Plant gold recovery increase resulting from the installation of High Shear Stators was 1.1 per cent, with a 1.9 per cent increase in flotation gold recovery and 5.4 per cent increase in flotation sulfur recovery. Based on the 1.1 per cent recovery increase and total project cost of less than $200 000, the High Shear Stator Project NPV was $8 200 000 with a 0.25 year payback period.

Jan 1, 2006

The resources industry is unique in that the finite nature of resource deposits requires a participant to be constantly locating and developing new ones to replace those that are depleted. An effective growth strategy that enables new project developments to be brought on line in time and within budget is therefore of fundamental importance to any mineral resources company. This paper seeks to identify the role of the development project in the company's overall growth strategy and the key performance criteria that a development project must achieve in order to allow a company to meet its growth objectives.

Jan 1, 1997

By Jacobs M

After a methane explosion in a coal mine a pre-determined crisis management procedure is instigated. As the process rapidly evolves the inevitable question arises - are personnel trapped underground, are they alive and can they be rescued without putting the lives of the rescue crew at risk? This is a very emotive question with many sub-questions such as; could anybody have survived, is there the potential for a secondary explosion and is there a `window of opportunity' before that secondary explosion occurs?To determine if that window of opportunity exists two fundamental elements must be in place; a method of determining the atmosphere at key points in the mine and a method of predicting the course of change of that atmosphere with respect to time. The first element can be achieved if the tube bundle system is intact and drawing samples from known points, alternatively boreholes can be drilled from the surface. The second element can be realised by utilising a sequence of computer generated control charts which have a time axis, a percentage combustibles axis, the upper and lower explosive limits of the current atmosphere and a prediction option which allows the user to look at the potential changes in the atmosphere over a set period of time. These control charts would be part of the mines on-going crisis management system rather than a tool to be used after an explosion had occurred.

Jan 1, 1998

The need for ventilation around mine workings derives from the various gases found in mine atmospheres and CH4, the principal diluent is in quantity depending upon several factors. Several of these are seam thickness, depth of cover and working method and the French Regulations typify controls on coal mine ventilation. There are many factors affecting production of CH4, in addition to coal production, such as the geological setting of the working seam, the geometry of workings and the rates of advance. The possibilities of spontaneous combustion should not be overlooked. The complexity of high production modern colliery layouts is such that sometimes there maybe 200 airway branches. There are specific differences in ventilation networks between the mining methods of rooms and pillars, shortwalls and longwalls as affecting resistance losses, as well as necessary airflows and ventilating

Jan 1, 1983

By T J. Scanlon

Heavy minerals recovered from recently discovered deposits in the Murray Basin are proving to be somewhat more difficult to process into saleable ilmenite products than ilmenites from existing operations. This is due to the nature of the gangue minerals present, the impurities in the valuable minerals and the size distribution of the mineral assemblages. Ilmenite product quality, in particular, can be adversely affected by any of these factors. Over the past two years the authors have been involved in assessing the potential to manufacture ilmenite products from a variety of mineral sand deposits in the Murray Basin. The steps undertaken to define the potential products and develop suitable flowsheets have evolved in parallel to the exploration efforts, in cooperation with companies undertaking exploration in the Murray Basin. A combination of an understanding of detailed mineralogy, application of magnetic fractionation and modification of magnetic susceptibility of the ilmenites has in all cases, been successful in improving ilmenite product quality. The targeting of particular ilmenites to specific downstream processes for TiO2 pigment manufacture is the most challenging aspect of this development.

Jan 1, 2001

Christmas Island contains large deposits of phosphate minerals varying from high-grade calcium-phosphate (apatite) to lower grade iron and'aluminium phosphate (crandallite/millisite). The surface material is dominantly C-grade (Fe/Al) phosphate profiling into B-grade, a variable mixture of C- and A-grade ores, before reaching the high A-grade phosphate (apatite) which overlies a limestone Karrenfeld Base formation. A-grade ore is the basic phosphate used for the manufacture of superphosphate and phosphoric acid, whilst B-grade contains amounts of iron and aluminium which are unacceptable for these acidulation processes. Research into methods of separating the finer iron and aluminium phosphates from the coarser calcium phosphates has led to the development of wash-screen processes enabling recovery of 50 to 60%, as A-grade phosphate. Developmental stages included laboratory investigations, mineralogical studies, pilot tests leading the initial 20 tph prototype production unit and the current 100 tph production wash/screen plant, commissioned early in 1970 at Christmas Island.

Jan 1, 1971

EQUIPMENT TO BE DISCUSSED It is the intention of this paper to discuss the transporting of large skid mounted equipment and track machines around open cut mines. By large I mean 100 to 350 tonne capacity being trans- ported on minesite lowloaders and the capability of moving loads of 300 to 1200 tonne by other means. It is also possible to move larger loads. The main factor in transporting large loads is eco- nomics and is a balance between the cost of the transporter and the increased production from the equipment being moved. For example it could be possible to shift a 7000 tonne dragline faster than their own means of propulsion, being the "walking feet" method. However for the cost of $10 to $12,000,000.00 or more you can afford to walk the dragline and suffer the production loss. Let us concentrate on the economically realistic. BOSICH FBT MINESITE LOWLOADERS 100 TO 350 TONNE CAPACITY. Why initially consider having such a transporter? Our experience has shown that initial enquiries evolve from mines requiring to move large drills, 50 to 200 tonne weight and large hydraulic excavators or backhoes which are track mounted. The reason for shifting them is to move equipment from a mining face to enable blasting, to remove to the central workshop for repairs, overhauls and routine maintenance, to transport equip- ment from one mine face to another, and for drills, to move from one drilling pattern to the next. The cost in terms of time lost and extra wear on tracked equip- ment easily justifies the cost of the transporter. The tracks on large drills and shovels are not intended for long distance walk- ing. These tracks are designed to move the machines to position for drill holes, or moving around the mine face. Long distance travel, ie generally 1 km or more, results in overheating of track rollers, track drive components and accelerated wear on tracks.

Jan 1, 1989

Reconciliation involves the collection of tonnage, grade (quality) and contained metal (product) data from disparate and hopefully independent sources. Examples are exploration data, production sampling data from blastholes or drawpoints, and process plant data. These data may be compared by means of ratios (factors). The F1 factor usually relates short-term (ore control) model tonnages, grades and metal content to ore reserves depleted. The F2 factor usually relates received-at-mill tonnages, grades and metal content to delivered-to-mill = production tonnages, grade and metal content. The F3 factor is F1 × F2 and enables a comparison of a mineÆs ability to recover the tonnage, grade and metal content estimated in ore reserves. The F1 factor measures the accuracy of orebody knowledge in the ore reserves to the demarcation of ore and waste by ore control (short-term model). The F1 factor may be used to check and calibrate the selectivity of mineral resource models and/or planned dilution assumed in transfer from mineral resources to ore reserves. The F2 factor enables a check on unplanned dilution entering the ore stream between ore control and the mill. Using the factors it is possible to calculate a monetary value on improvements in the accuracy of orebody knowledge, selectivity and the effects of dilution and ore loss. Reconciliation should be an implicit part of the mining process, and reconciliation targets should be a key performance indicator for well-run mines.

Sep 26, 2011

By Hanley J

Coal winning in the Latrobe Valley exceeds 45 mtpa uses a small number of Bucket Wheel Excavators and high speed conveyor systems. While this equipment offers many advantages in the production cycle, incorrect use can lead to low productivity and risks to the safety of the operators and equipment. The mining equipment is of high capital value and easily damaged when used outside the correct operating range. In the extreme case, this can result in total machine collapse, having major implications for personnel safety as well as production and costs. With an active productivity improvement program in the Latrobe Valley in the last two years resulting in a 50 per cent reduction of personnel, many experienced operators have retired. Mine management are facing the urgent need to rapidly train new operators to maintain high productivity levels and reduce the risk of accidents to personnel and high capital cost plant. With the assistance of the Central Gippsland College of TAFE a Certificate Level course has been developed for open cut operators. The course covers all essential training needs for the Latrobe Valley mines. The training is developed from National Competency Standards, allowing transfer of skills, and is flexible to suit other enterprises. It has been written for self-paced learning with the total job understanding, and to have competency-based learning outcomes, training tasks and assessments built-in to modules. With the introduction of this new training program, management is convinced that the element of risk within the mine will be significantly reduced. For these reasons it is an ideal training model for other enterprises.

Jan 1, 1994

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

Kamhalda is located within the Yilgarn Craton of Western Australia, specifically in the Norseman - Wiluna greenstone belt. Numerous nickel sulphide deposits have been mined at Kambalda with I I mines currently operating. For several years, a program of in-mine geophysics has been operating at Kambalda, with downhole electromagnetics (UHEM) one of the key techniques used. Three case studies illustrating the uses of UHEM in mines are presented here. In the first example, the Helmut South deposit was discovered as the result of an extensional exploration program. The first drill hole in the program intersected ore width and grade mineralisation at around 760 in depth. Two subsequent holes intersected subgrade mineralisation. DHEM surveys were completed in each of these three holes, with anomalies recorded indicating that a large conductor was located directly south of the first hole. The next hole intersected this target, for an intersection of 21.6 in at 3.5 per cent Ni. DHEM continued to play a role as the exploration program proceeded, providing drill hole targeting based on anomalous responses recorded in each drill hole. In the second example from Carnilya Hill, old drill holes were surveyed with DHEM in order to search a large section of prospective contact for massive ore pods. An off-hole anomaly was detected and subsequent mining discovered a small but high-grade pod of ore which was extracted for a considerable profit. Carnilya Hill has limited reserves and discoveries such as this, assist in keeping the mine operating. In the third example from Victor, a program of drilling intersected thin ore profiles in an interpreted flanking position. Without massive ore close by, these intersections probably do not constitute economic mineralisation. DHEM surveys of three holes did not detect any conductors. The area is now regarded as sterilised of significant massive ore and exploration efforts and dollars can be focused in other areas. These three examples demonstrate the type of successes that can he achieved through the use of DHEM.

Jan 1, 1997

I would like to start by thanking The AusIMM and CSIRO for organising this excellent conference and inviting me to give a keynote address. Today I will focus on some broad observations of our industry, and leave the technical discussion to my colleagues who are presenting specific papers covering a wide range of topics. In preparation for this paper, I did a little research into the early history of the Pilbara iron ore industry. I was fascinated to read a quote attributed to Harry P Woodward, the Government Geologist in the late 19th century, before Federation. Mr Woodward described the Pilbara as an iron ore country and observed that æthere is enough to supply the whole world should the present sources be worked outÆ. Mr WoodwardÆs prediction could be viewed as wishful thinking and certainly at Hamersley Iron I would gladly envisage the Pilbara supplying the worldÆs entire iron ore needs! In reality, Western Australia accounted for 162 million tonnes or 36 per cent of seaborne trade in 2001. An impressive effort, but not quite the total world supply as Mr Woodward imagined. But we shouldnÆt dismiss these historical musings out of hand û perhaps we could see it as a challenge for the industry to æwork outÆ the present sources. We all know there is abundant iron ore in the Pilbara, and I expect it is only a matter of time until our collective technical expertise and sheer hard work will enable us to utilise its greater range of ore types. Opening up new markets will be a key pathway to creating additional value from the Pilbara ores. Today I will examine the state of play of our industry and the major influences that shape our business at present, before considering what the future might hold for us. I canÆt guarantee the accuracy of my crystal ball, but the stability and long-term nature of our industry does enable some reasonable hypotheses on where we are heading. I will also spend some time examining the way in which the iron ore producers are working to maximise the value of their resource base and obtain more from their existing capital assets.

Jan 1, 2002

By Little T. N, Bettess D

For many mining operations the challenge of equalling World Best Practices has become the key motivator for increasing mine productivities and for lowering total costs. In most instances this will only be achieved if mines optimise their total system rather than minimising specific costs within unit operations. In the past, drilling and blasting have been viewed as a cost to be minimised rather than operations which should have their impacts fully leveraged. Once a hardrock orebody is defined the activity which has the most substantial impact in determining the efficiency of a mining operation is the blasting. The output from a blast affects every downstream operation; only by understanding the extent and interactions can the mine be optimised. Substantial improvements to hardrock mining, quarrying and excavation operations are achievable. Instead of seeking the regular one to three per cent improvements based on reduction of consumables, mine operators would be well advised to go for much bigger targets of ten to 30 per cent by fully leveraging the drill and blast operations.

Jan 1, 1995