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The Bellambi Coal Company Limited com menced longwall mining at South Bulli Colliery in 1965. At present it operates three long- wall units in two seams. Although results to date have been less successful than planned, it is apparent that this type of mining has tremendous potential in the particular conditions at South Bulli. Massive sandstone strata above the Bulli seam is the controlling influence on face conditions. The earliest equipment proved to be inadequate and the Company has progress- ively replaced and upgraded the roof supports and ancillary equipment so that the present units are capable of producing high and consistent outputs.

Jan 1, 1976

By Minchinton A

CPeX is a non-ideal explosive performance prediction model. The model takes into account the rate of energy release, the extent of chemical reac- tion and the effect of confinement on energy release. The model resolves the explosive energy into `shock' and `heave' com- ponents as a function of explosive type, hole diameter and rock type. The predictions of the model are compared for a bulk emulsion, and a prill-doped bulk emulsion in soft rock. The predictions, based on calibra- tion of the model with simple unconfined detonation velocity measure- ments, show the significant effect of non-ideality on explosive Performance.

Jan 1, 1988

By T A. J Hopper, S Mukkisa, K-O Ott, D Palmer

RIG Technologies has developed new technology that can successfully acquire high quality natural gamma ray (GR) and hole deviations, downhole while drilling, on reverse circulation drills. This technology survives the hostile downhole environment with shocks of between 400–2500 g for 7– 10 days at a time. The Logging While Drilling (LWD) service eliminates the need to run in-rod surveys, either by the driller or by wireline trucks and crews. This time saving is in the middle of the drilling process, thus enabling drills to keep drilling and increase their productivity. Additional to the natural GR and directional survey, the downhole tool is equipped with sensors to measure the downhole dynamic response of the drilling system providing insights into rock hardness, density and potentially clay types. These parameters have never been acquired behind the hammer before and coupled with surface measurements from the drills themselves, form a rich data set for trainable machine learning algorithms shortening the time to receive advanced geophysical answer products from sometimes months, to live feeds directly from drills (Hopper, 2019). Alive, high speed, two-way data link between surface data acquisition systems and downhole geophysics tools has been established and incorporates calibrated surface measurements of dynamic forces directly on the drill string to match up with those measured downhole. Receiving live streams of natural GR and hole deviation surveys as the drill is drilling allows true remote decisionmaking with live data available anywhere in the world. The combined data from surface and downhole dynamics builds a data set that could begin to enable true optimisation of autonomous drilling processes.

Nov 8, 2021

Not so many years ago the reason for an inadequate result from a geophysical survey was insufficient data or poor quality data. In many instances such as gravity, magnetic and radiometric surveys, both these constraints are vanishing or have vanished. High quality sensors, improved data storage, accurate differential GPS and top quality interpretive software now enable the interpreter to understand not just the cause of the anomaly but the host environment in which it resides. Examples of potential field data and also data provided by the more complex electromagnetic systems, from Australia Ghana, West Africa, are used as illustrations.

Jan 1, 1997

By Yu H, Wan B

40 percent of the coal reserves and 40 percent of the ouput of coal in China is of thick coal seams. The sub-level caving in Yangguan has evolved together with the hydraulic supports, to provide recovery rates today of 80 to 85 percent, waste ratios less than 10 percent and daily outputs exceeding 7,000 tonnes. Matching of rate of shearing bottom coal to caving of top coal is most important to achieve "simultaneous" operations. Spontaneous combustion in the goat, gas, including in the goal, and dust, are particular safety hazards which are combatted with various stringent measures.

Jan 1, 1991

By Conochie DS

SIROSMELT is a successful new pyrometallurgi- cal furnace system using a top-entry lance which can be submerged in both slag and matte. The lance is of simple construction, and is cooled by process air. Pilot plant work commenced in the CSIRO Division of Chemical Engineering in 1972 using a 50 kg batch reactor. This paper traces the development of the technology through various slag cleaning and smelting processes up to a scale of 5 tonnes per hour continuous feed. Strong co- operation between CSIRO and the Australian smelting industry has contributed greatly to the success of SIROSMELT.

Jan 1, 1984

By Floyd JM

Conventional smelting reactor systems were designed to recover only one main element from their feedstocks. They did not possess sufficient flexibility to allow optimisation of co-production of multiple values from a complex feed.New reactors such as Sirosmelt and Top Blown Rotary Converters are providing new possibilities for making separation between components and this is of great significance for the complex feeds which are becoming prevalent in the metal extraction industry.Process routes using chemical procedures which take advantage of the flexibility of these reactors will be discussed in relation to a number of possible feedstocks.

Jan 1, 1985

By Bigu J, Grenier M. G, Knight G

Particulate control is a major concern in underground mining and the subject of continuing research world wide. In Canada the federal government's Mining Research Laboratory at EIIiot Lake, Ontario, has been using two aerosol counters to aid its investigations. Specific studies with the units include: a) evaluating total and elemental size efficiencies of dust filtration units: b) characterizing the dust particulate cloud from different mining operations: and c) determining dust transportation characteristics.

Jan 1, 1988

Standards in the public reporting of resources and reserves in Australia have dramatically improved since the implementation of the Australasian Code for Reporting of Mineral Resources and Ore Reserves (The JORC Code) in 1989. Whilst the JORC Code states clearly that Mineral Resources and Ore Reserves are imprecise calculations and should be treated as estimates, there is strong evidence that many people regard them as fact, including some accountants, directors, auditors and investors. Mineral Resources and Ore Reserves are key inputs in the valuation of a mining company and the determination of financial performance. Geological knowledge is the foundation upon which Mineral Resources, Ore Reserves and investment decisions are made, however this information carries with it substantial uncertainty. Case studies and company reports have established that errors derived from inadequate geological inputs have led to reduced profitability in operating mines and in extreme cases the premature closure of mine operations. Whilst there are many causes of mine closure and reduced profitability, including commodity prices and exchange rates, the cumulative effect of all geological uncertainty contributes significantly to the erosion of the credibility of mining within the investment community. There are a number of methods used to characterise and model uncertainty in Mineral Resource and Ore Reserve estimation. Empirical mining indexes, sensitivity analyses, Monte Carlo simulations and Conditional simulations are used to identify and estimate geological uncertainty, notably the quantification of uncertainty in grade and tonnage estimates. These techniques have not generally been applied to estimating geological uncertainty associated with key Ore Reserve inputs such as appropriate mining technique, equipment selection, production rate, mining dilution, stability requirements, materials handling, metallurgical processing, product quality and waste storage. New software tools are needed to model the entire mining process with all its geological and other interdependencies, enabling all uncertainties to be separately identified and estimated. By its very nature, mining involves the assumption of significant technical, financial, political, environmental and social risk. Success comes by understanding and managing these risks and consequently the mining industry will never choose to reduce the level of geological uncertainty to nil. The ultimate aim of improved identification and estimation of geological uncertainty is to quantify inputs into the Ore Reserve process, allowing a company to assess the risks and manage these accordingly. This approach is relevant to feasibility studies for new projects as well as life-of-mine planning through to the weekly schedule at existing mines.

Jan 1, 2003

By T Y. Ko, Y S. Kang, S J. Park, J H. Hwang

The lunar subsurface, particularly the lava tubes formed by ancient volcanic activity, presents a promising environment for establishing safe and sustainable human habitats on the Moon. Tunnel Boring Machines (TBMs), widely used for excavating tunnels on Earth, offer a potential solution for developing these subsurface spaces. However, the unique lunar conditions, including extreme temperatures, high vacuum, radiation, and the extraordinary strength and abrasiveness of lunar rocks, necessitate significant adaptations to existing TBM technology. This study investigates the feasibility of utilising TBMs for lunar subsurface exploration and base construction, addressing the challenges posed by the harsh lunar environment. We review previous conceptual designs for lunar TBMs, highlighting their strengths and limitations in addressing these challenges. Additionally, we explore innovative excavation methods, such as microwave-assisted rock weakening and undercutting techniques, to enhance the efficiency and effectiveness of lunar TBM operations. By evaluating the geological characteristics of the lunar crust and analysing the potential of lava tubes as launching points for TBM operations, this study provides a comprehensive assessment of the technical requirements and operational considerations for lunar TBM implementation. The findings of this research contribute to the growing body of knowledge on lunar base development and pave the way for future human exploration and utilisation of the Moon’s subsurface resources.

Sep 1, 2024

Characterising the weight percentage of each mineral in base metal ores is an integral part of assessing the quality of an ore in terms of its processing properties. The Rietveld method, which uses X-ray diffraction data, has been applied to routinely quantify the minerals in lead/zinc and copper ores from Mount Isa Mines Limited and supergene copper ores from Ernest Henry Mining as well as their related products from the concentrators. The Rietveld method has been tested by comparing Rietveld mineral data with a standard sample with known mineral weight percentages and comparing Rietveld mineral data with mineral data calculated from elemental assays where the element only exists in one mineral such as lead in galena. Where this latter situation does not occur, the Rietveld method has been checked with both elemental and optical microscope data. In all cases, there is a good correspondence between the Rietveld data and the data it was checked against with absolute differences generally in the range of 0.5 to 3 wt per cent. The Rietveld method generally quantifies all minerals occurring over 1 wt per cent in one analysis and is less expensive and more routine compared to traditional methods such as optical microscope point counting. The Rietveld method can be applied to many stages of the mining cycle such as exploration, feasibility studies, mining, minerals processing and for environmental studies.

Jan 1, 1998

The subject of government involvement in industry is, to say the least, a touchy one. For many it conjures up thoughts of socialisation or nationalisation. For others it is a desirable objective and is seen as a means of social reform by giving government a greater say in the control and distribution of human, financial and natural resources for the betterment of the community. Whatever your point of view, it is difficult to deny that government involvement exists to lesser or greater degrees in all industries. The mining industry is no exception and the degree of government involvement is probably greater than it is in other industries. I think it is important to remember when talking about government involvement in industry to recognise that there are different types of involvement and that all governments have a right, if they so desire, to become involved in whatever way they choose. The decision of a government to increase its direct or indirect involvement must, of course, be taken in the national interest. Governments, if we are still old fashioned enough to believe in ministerial and electoral responsibility, must make up their own minds about whether their actions are in the national interest and they must be prepared to accept the consequences of that action, good or bad. For instance, they must decide

Jan 1, 1975

By E K. Chiw, S-M Jung, S M. Masuka, ika

The world reserves of high-grade iron ore have depleted necessitating the need to utilise any existing natural iron ore deposits to meet the demands of the world’s expanding economy using hydrogen in the reduction process to curb CO2 emission. These low-grade ores include iron ores with high phosphorus content. The thermodynamic conditions in the blast furnace allow for the reduction of phosphorus that readily dissolves into the molten iron. Phosphorus in the gaseous state readily dissolves into the molten iron and therefore must be removed due to its negative influence on the mechanical properties of steel. The removal of phosphorus from molten iron is difficult causing the phosphorus to concentrate in metallic iron. The aim of this study is to provide basic knowledge on the phosphorus distribution after reduction using the CO-H2 and possibly provide the optimum conditions for phosphorus partitioning into slag, increasing the probability of its removal by magnetic separation. Total porosity, pore size distribution and surface area of the pellets used were measured using a mercury pressure porosimeter. The reduction was carried out using thermogravimetric analyses (TGA). The reduction rate increased with increasing H2 and was highest when 100 per cent H2 was used. Metal elements distribution in the reduced pellet was clarified using electron probe microanalysis (EPMA) and showed that phosphorus was distributed in the same areas as Ca. More phosphorus was concentrated in slag when 50 per cent CO–50 per cent H2 was used, increasing the probability of dephosphorization using magnetic separation. The concentration of phosphorus into slag was related to the rate of reduction. Further investigations into the reduction kinetics of this ore by CO-H2 is suggested to validate these findings. Nevertheless, a comprehensive thermodynamic analysis of the reduction of phosphorus containing phases found in iron ore with carbon, CO and H2 was provided to assist in selecting the optimal reduction experimental conditions.

Sep 18, 2023

At the beginning of this year it was my pleasure and responsibility to take over the Presidency of our Institute from Mr A. A. Parish who, as did his predecessors, filled the office with distinction. It is a great privilege to address you as President and it is an occasion for my wife and family, and I am most grateful for your inviting them to the buffet dinner. Our Secretary (Miss Jacka), who processes all Presidents, has told me that there are neither questions nor discussions on Presidential Addresses, and that being so, I felt free to select a controversial topic. The address I have prepared is not strictly true to label; because I intend to include also the effect on agricultural production in Australia if Britain joins the European Economic Community (i.e. the Common Market).Three points of view are1. the European, which is one of equanimity deriving from the initial brilliant success of their scheme,2. the British, which is one of anxiety not to miss the bus, coupled with a commendable wish not to inimically affect existing Commonwealth arrangements,and3. the Australian, which is one of alarm.In England all are drawing their own conclusions on the subject and views range from the extreme desirability, to the extreme undesirability, of the United Kingdom joining.No one in Britain wants Australia, or New Zealand, to...

Jan 1, 1962

By A Jafari, N Khalili, M Vahab, P Broumand

This paper presents the implementation of the eXtended Finite Element Method (XFEM) in the general-purpose commercial software package COMSOL Multiphysics for multi-field thermo-hydromechanical problems in discontinuous porous media. To this end, an exclusive enrichment strategy is proposed in compliance with the COMSOL modelling structure. COMSOL modules and physics interfaces are adopted to take account of the relevant physical processes involved in thermo-hydromechanical coupling analysis, namely: the mechanical deformation, fluid flow in porous media and heat transfer. The model preprocessing, level-set-updates, coupling of the relevant physics and postprocessing procedures are performed adopting a coherent utilisation of the COMSOL’s built-in features along with the COMSOL’s LiveLink for MATLAB functions. The capabilities and performance of the proposed approach are investigated by examining several multi-field thermo-hydro-mechanical simulations with reference to the block caving process in mines.

Nov 29, 2022

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 A Morris

The Express Rail Link (XRL) will provide high-speed rail services from Hong Kong to Guangzhou and a connection to the national high-speed passenger rail network serving major cities throughout Mainland, China. The HK$ 67 B (NZ$ 11.5 Billion) project is of great strategic importance for Hong Kong and is being implemented to a very tight schedule, from early 2010 with completion targeted for 2015.The works include a 15 platform terminus station in West Kowloon, 26 km of twin track tunnels from the terminus to the Hong Kong/Shenzhen boundary at Mai Po, tunnel vent shafts/adits/emergency rescue siding and a stabling siding facility. Trains on the Hong Kong section are intended to operate at speed up to 200 km per hour and up to 350 km per hour on the Mainland section.This presentation will provide an overview of the entire XRL project, with a focus on the challenging geotechnical and spatial constraints on the tunnel works. This is an abstract only. No paper was prepared for this abstract.

Mar 8, 2011

By Mez W

the German ruining industry uses different residues for hackfilling and stowing. A hydraulic pipe conveying technology for these materials has shown advantages for the transportation into the mine. Pipeline conveying systems are able to bridge long distances, they save room within the underground workings and they save staff and costs. Absolutely necessary for successful use of the hydraulic conveying technology is the knowledge about the unusual non-Newtonian flow properties of solid/liquid mixtures like pastes and slurries. The flow resistance of these materials cannot be described easily by one viscosity. Owing to a yield point and a pseudo-plastic behaviour the viscosity changes with the shear rate and with the streaming velocity inside the pipe. Also these flow behaviours depend very sensitively on the liquid/solid-ratio, often so dramatically that gravimetric or volumetric dosing equipment is not in a position to control the production of backfill pastes. Quality changes of the solid raw materials (particle size distribution, density, mineralogical composition) lead to additional difficulties. The first experiences with hydraulic backfilling plants were troubled by plugged pipes. a bad backfill quality caused by unnecessarily high water content and high costs for chemical binders to solidify the backfill. The installation of viscosity controlled paste production leads to success with the hydraulic backfill technology. A development of the l)MT, a bypass pipe-viscometer, has been the key technology. The system is able to analyse on-line, difficult, sticky and abrasive substances and determine their non-Newtonian flow properties. Because the system measures real physical values it is in a position to pre-calculate process relevant parameters like the pressure drop of the backfilling paste in the conveying pipeline. Newer types of the viscometer system also measure the slurry density and calculate its composition. These systems have proven a success controlling backfill paste production plants. They offer it secure prevention of pipeline plugging and a production of high quality backfill pastes with a water content as low as possible.

Jan 1, 1998

By Martinick WG

In July 1986, Cable Sands (W.A.) Pty Ltd commenced mining for mineral sands at Minninup, approximately 16 km south of Bunbury, Western Australia.The area being mined is from the heel of the foredune to the rear of the hind-dune. The vegetation is mostly native vegetation with some old degraded pasture.The mining operation will be by suction cutter dredge, with continuous dredging, mineral separation and re-depositing of the sand.

Jan 1, 1986

By Burman B. C

This paper describes studies into two particular aspects of the Lochiel deposit which formed part of feasibility level geot2chnical and hydrogeological investigations for proposed open cut mine development. The two aspects were depressurisation of thick beds of silt located through the profile and the determination of characteristics and origins of soil structure and their effect on pit stability. The studies were very detailed and multi disciplinary and highlight the integration of geology, geotechnics, hydrogeology and mining that is required for mine development studies. It is considered that as more marginal deposits are developed throughout the world the demands for efficient economic mining together with in- creasing scales of operation will require simi- lar types of studies. As such the studies pre- sented herein are likely to be a forerunner to a,emerging trend for development of open pit mines in difficult ground and water conditions.

Jan 1, 1986