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By Lama R. D

The Australian underground coal mining industry is undergoing major changes. This paper analyses the technologies presently being researched in mines, and discusses their utilisation as major contributors in the underground mining of coal in Australia over the next 20 years. It describes the problems that underground mining of the year 2000 will face and the possible solutions to those problems based upon results of present day research. Methods, equipment and organisational requirements are outlined. Developments in micro-electronics, computerisation and monitoring will require a new look into human resource development, education and training, and organisation to meet the challenges of the 21st century. The mining system's philosophies of the future are Outlined.

Jan 1, 1986

By Granholm S

The current emphasis within the mining industry to reduce the cost of production has stimulated interest in the field of maintenance and operational reliability of capital intensive mining equipuent. The failure consequences of these machines have major safety and economic implications for a mine operator. The reliability centered maintenance (RCM) approach has been found cost effective for equipment maintenance and for achieving high level system perform- ance by many organizations such as airline, military, chemical, process and manufac- turing industries. In this paper an attempt has been made to describe in brief the basic concepts of a RCM approach, the methods of RCM analysis and its cost effectiveness for maintenance of equipment. Since this approach is comparatively new for the mining industry, suitable examples are given to illustrate the case.

Jan 1, 1988

By Vernon PN

The Eossing Uranium Mine is a high tonnage low grade open pit operation using acid leaching for uranium extraction and ion exchange and solvent extraction for solution purification. Advanced technology, much of it computer based, has led to major economies that have contained operating unit costs over the last four years in the face of double figure inflation. An improved ore reserve block model and mine planning system have achieved a considerable reduction in the stripping ratio. Drilling and blasting costs have decreased some 25%, mainly by the introduction of heavy ANFO explosive. A centralised computer control centre for the metallurgical plant has increased labour productivity resulting in improved process control. The all-staff workforce is united with management in the objectives of creating a safe, healthy, working and living environment and a prosperous company, capable of contributing to the wellbeing of the nation and the shareholders. This situation has been brought into being by an equal opportunity policy coupled with a management system emphasising open two-way communication through all levels in the organisation. The success of this policy is highly apparent in the morale and productivity of the workforce.

Jan 1, 1986

Nauru Phosphate, which is one of the world's highest grade deposits discovered to date, contributed in 1969, 2.2 million tons of the total world production of 77.7 million tons. Phosphate production, which is the major source of revenue for the island nation, is carried out by the Nauru Phosphate Corporation, headed by a Government appointed Board of Directors. The complete mining operation, including ship loading techniques, is discussed along with proposals at present being investigated to upgrade the Quality of the product.

Jan 1, 1971

By L J. Reynolds

Gold mineralisation at the Globe Progress deposit is hosted by a geologically complex zone of shearing and brecciation, within a package of deformed metasediments. Mineralisation styles range from quartz breccias and lodes to sheared clay pug zones and disseminated sulfides. A review of the diamond drill core intersections through the deposit indicates that critical hanging wall and footwall contacts can be a combination of sharp or gradational; visual or non-visual boundaries. Approximately 60 per cent of mineralised contacts can be confidently identified visually, particularly where associated with veining, distinct brecciation or shearing, and high sulfide content. However, the gold grade and distribution of disseminated mineralisation can be extremely difficult to estimate visually, with implications for resource estimation and grade control when mining. Using observed drill hole geology and assays, a new geologically based model for the gold mineralisation has been constructed for the deposit to reflect the expected variability of the mineralisation contacts. This new model will constrain resource estimation and also serve to act as a predictive model when open pit mining commences. Nevertheless, careful grade control practices such as drilling, trenching and supervised extraction of ore will be required to maximise ore recovery and minimise dilution during open cut mining.

Jan 1, 2006

By Kajioka H, Nakamura Y

Na2CO3 is a powerful flux for both dephosphorization and desulphurization in oxidizing atmospheres. In order to study refining with Na2CO3 and the nature of the Na2CO3 slag itself, hot metal (4Kg) was melted in Al203 crucibles in a high frequency induction furnace and oxidised with oxygen under Na2CO3 slag. The behaviour of Na2CO3 at high temperature was observed by thermobalance. It was found that dephosphorization ceases in a few minutes and [,P] after refining is easily lowered to less than 0.010%. [%P] after refining is affected by [Si], [P] of hot metal, the refining temperature and the consumption of Na2CO3. Desulphurization also ceases in a few minutes but it shows curious behaviour, increase of [S], decrease of (S) and increase in sulphur lost, during the latter half of run. [%S] after refining is also affected by [P] of hot metal, the refining temperature and the consumption of Na2C03o

Jan 1, 1980

While I contemplate the formidable catalogue of bodies and organisations participating in this Conference and the impressive array of qualifications chalked up after the names of the representatives I am indeed honoured to be invited to address you. When I consider the theme you have chosen for your conference I am also somewhat daunted: "The Twenty First Century - Mining for Mankind". It is indeed dramatic, challenging. But what, I ask myself, can a mere KCMG say to all you professional fellows and doctors and academicians? It is not for me to stray on to the more esoteric areas that you will be covering, thereby running the risk of teaching my grandmother how to suck manganese nodules. On the other hand it seems to me that you deserve more than the courtesies, not to say banalities, that are sometimes - sadly, and unjustly - regarded as the stock in trade of diplomats.

Jan 1, 1986

The Pasminco mine at Rosebery in north western Tasmania is a medium sized underground base and precious metals mine. In April 1992 a major wedge failure of approximately 5000 t occurred in the backs of a main access drive to the 18 level H Lens orebody. This collapse prevented access to 190 000 t of ore which had been scheduled for production in July - August 1992. At the time of the collapse, the mine was in a transition period between mining small pillar remnants of several other orebodies and developing to the new deeper J Lens orebody.The development at this orebody was behind schedule and it was necessary to find a cost-effective and timely alternative to a 75 m bypass drive around the fall area.A Lysaght- Fletcher multiplate steel arch was available on-site from a deferred surface road project and it was decided to use this arch to regain access through the fall area. Due to the danger of continued minor falls, the entire 18 m long, 3.95 m high x 4.5 m wide tunnel had to be assembled in the 4.7 m wide x 5 m high accesss drive and pushed into the fall area as a single unit.

Jan 1, 1993

By Lewis W. H, Leigh M. C, Mayercheck W. D

The U. S. Department of Interior's Bureau of Mines, in conjunction with a cooperator in the U. S. A., are developing a new highwall mining system (HMS) for coal extraction in unreclaimed and active contour strip mines. This prototype system is comprised of a computer-based remote control (CBRC) system to monitor and remotely control a thin-seam continuous miner (TSCM) and a 76*m long multiple-unit continuous haulage (MUCH) conveying system, plus other manually- operated support equipment located on the highwall bench. The TSCM and MUCH coal haulage system are both controlled remotely by a single operator in a protective enclosure at an ergonomically- designed workstation located on the highwall bench. Two other personnel work on the bench to operate other support equipment. Full-scale mock-up fabrications were employed in the design of the unique remote control operator workstation. The HMS should allow the safe and economical exploitation of increased coal reserves where they outcrop in hilly regions of the United States. It should also be competitive with conventional auger mining and other coal extraction techniques, with a productivity goal at a highwall site of 20 tonne/man-h. Extensive simulated surface tests of the miner and haulage system should be completed in early 1988 at Bureau test facilities at Pittsburgh, Pennsylvania. These will be followed by actual coal production trials of the entire system in 1988 at a highwall site in West Virginia/USA.

Jan 1, 1988

By Haslam C. O, Taylor S

Four historical periods of Australian lead-zinc-silver exploration and development are identified.In the first period, 1841-1900, Australia's deeply weathered surface yielded bonanza deposits. The outcrops of easily worked secondary ores, enriched in silver and lead, were discovered by prospectors with the incentive of production at times of high silver price. Districts discovered in this period still contributed, in 1982, 60 per cent of Australia's lead-zinc production, mainly from Broken Hill.The second period 1901-1944, was one of strong mine development but stagnant lead-zinc-silver exploration. Mount Isa was discovered and developed, but otherwise effort was devoted mainly to the mining of deposit extensions and to the metallurgical flotation of zinc. The deposit discovery rate was low but the discovery of Mount Isa was so significant that discoveries of this period contributed, in 1982, 30 per cent of Australia's lead-zinc production.The third period 1945-1972 was one of re-invigorated exploration.New geological and geophysical surveys, developing concepts of ore genesis, and worldwide comparisons of orebody settings improved target area selection. Evolving remote sensing methods, and rapid analytical techniques, assisted detection of lead-zinc deposits. Initiation of exploration led to discovery:1. in regions of previously unsuspected lead-zinc-silver potential (Sorby Hills, Mons Cupri, Golden Grove).2. of poorly exposed deposits in recognized mineral districts (Hilton, H.Y.C., Woodlawn, Elura, Que River).3. during active exploration for another commodity (Brown's, Woodcutters, Mary River, Beltana, Lady Loretla and Pegmont).The period saw a sustained growth in lead-zinc-silver production mainly from established operations. Mines discovered during the third period contributed, in 1982, 7 per cent of Australia's lead-zinc production.In the fourth period from 1973 to the present, exploration initiatives became fewer but resulted in continued discovery of poorly exposed deposits at Teutonic Bore, Thalanga, Benambra, Scuddles, Hellyer, and Jillawarra. Development initiatives strengthened in the period and production commenced at Woodlawn, Teutonic Bore, Que River and Elura; pre-feasibility work commenced at Scuddles, Hilton, Lady Loretta and Thalanga.

Jan 1, 1984

By J Zanganeh, M Ajrash, B Moghtaderi

Application of thermal oxidation is considered a promising technique in reducing fugitive methane gas from ventilation air methane (VAM). A typical thermal oxidiser operates with diluted methane and converts it to less potent greenhouse gases. However, having a thermal oxidiser in the vicinity of the coalmine exhaust shaft is a major safety concern as its high operation temperature increases the likelihood of accidental fire and explosion. The aim of this study is to investigate the application and effectiveness of side venting technique in reduction of deflagration consequences caused by methane gas. To address this importance a series of experiments were conducted on a detonation tube designed and fabricated as part of larger scale VAM Abatement safety project. The experimental work was carried out into two stages: examine the flame and explosion properties in a large-scale detonation tube to get reliable data; and then design and employ a venting system into the detonation tube to verify the effectiveness and performance of the venting against the flame and explosion.Results corresponding to this study show that the side vent duct with venting coefficient magnitude of 37 had a significant influence on methane flame deflagration and the explosion characteristics. The maximum pressure rise at the detonation tube reduced approximately 20 per cent to 32 per cent by applying the side venting duct. Also, the data shows that the venting damped the pressure oscillation after the flame deflagration which eventually reduced the system instability. Finally, by applying the venting technique the expected level of damage due to the dynamic pressure reduced to the level of limited building damage.CITATION:Ajrash, M, Zanganeh, J and Moghtaderi, B, 2017. Application of side venting technique in mitigation of methane – air explosion and flame deflagration in ventilation air methane, in Proceedings Australian Mine Vent Conference 2017, pp 153–258 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Connell JE

The Worthing Mine near Hallett Cove. 20 km southwest of the cite of Adelaide, belongs to Aus- tralia's first mining era, which took place in South Australia between 1841 and 1851 (Figure 1). Oper- ations began in 1849 only six years after the com- mencement of metal mining in Australia at Glen Osmond. Although not as historically significant as Glen Osmond (1841), or the much larger copper mines of Kapunda (1844) or Burra (1845) its importance lies with its Cornish enginehouse and chimney. The Worthing enginehouse, built in 1851-1852 is the oldest remaining in Australia and certainly the most significant relic of Australia's first mining era. Six other stone enginehouses were built during that period: at Kapunda in 1848 and 1850: at Burra in 1849, 1850 and 1851; and at Tungkillo in 1849. All of these houses have long since dis- appeared although the foundations of one (Kapunda, 1850) still remain. The significance of the Worthing site is enhanced by its magnificant environmental setting in the bare, steep valley of Field River. Currently (1986) the Worthing Mine is the only site within the City of Marion which is on the Register of State Heritage Items. The site is also included in the Classified List of the National Trust of South Australia and on the Register of the National Estate.

Jan 1, 1987

Recovery of gold by smelting zinc dust concentrate has been carried on at Lake View and Star, Ltd., since July, 1930, when the Merrill-Crowe precipitation plant was first put into operation.Part I describes the development of current gold-room practice, commencing with the clean-up of the MerrillCrowe plant, a procedure that has not materially changed since its inception, and then shows how modifications to straight roasting and smelting became necessary, following a gradual increase in the copper content of the ore treated by the mill.Present smelting practice converts most of the copper into a mixed copper-lead matte, thE sulphur being supplied by the addition of flotation concentrates containing about 35% sulphur as pyrite. The process yields gold bullion of a sufficiently high grade to send to the Royal Mint, but until 1943, suffered from the disadvantage of giving matte and slag by-products high in gold and silver, that were not recovered directly but had to be sent to a smelter.Part Il gives details, of experimental work cnrried out since 1943 which led .to a process for the satisfactory and economic recovery of not only the gold and silver, but also the copper from these, hitherto, troublesome by-products. Nevertheless, incidence of matte in a smelt has always been considered undesirable, and it is hoped that eventually it will be obviated by removing most of the copper from the zinc slime before smelting.Part III indicates the methods by which this might be achieved, and outlines the experimental work that has been done up to the present.

Jan 1, 1948

By Rigby D, Gould K. W, Hart G. H

The variation in chemical and isotopic composition of hydrocarbon gases generated from humic source rocks in the Cooper Basin, the orth West Shelf, the agoorin oil shale deposit. ollinsville and the southern Sydney Basin is reviewed, discussed and interpreted.The primary composition of gases generated in and released from such source rocks appears to be very largely controlled by the degree of dispersion of the organic material. For example in eoaly shales, where the degree of dispersion may be high, products as generated may escape into surrounding inorganic structures where further maturational reactions may proceed. On the other hand, when the organic materials occur in massive form, as in coal seams, the hydrocarbons generated tend to be retained within the coal. Further cracking to the stage of methane generation is usually required before release of hydrocarbon products is significant.Secondary factors of importance in determining seam gas composition in the Bowen (Collinsville) and southern Sydney Basins are the invasion of coal measures by carbon dioxide from external magmatic sources and/or the vertical diffusion and loss from the surface ofgases generated at depth.Isotopic measurements of gas composition have been particularly valuable in determining the origins and histories of the gases examined, in demonstrating when gases are of mixed origins and in the prediction of gas quality in exploration.

Jan 1, 1985

By F Kock, Y Sulianto, T Trott, B G. Putland, D Morgan

"Northparkes installed and commissioned a secondary crushing circuit in 2010 to debottleneck the semi-autogenous grinding (SAG) mill constrained grinding circuits. Following further improvements to the circuit (inclusion of a double deck vibrating screen), the project successfully delivered finer feed to the SAG mill. The result of this project was an increase in the milled tonnes from 5.6 Mt/a in 2012 to 6.0 Mt/a in 2013.The increased throughput rates introduced new challenges with the circuit becoming power limited. How to best optimise the available comminution power, while delivering the optimal particle size to the flotation circuit was made the key optimisation objective. To achieve this objective, Northparkes initiated a project that included engaging comminution experts. Recommendations included changes to the SAG mill including mill lifter design, increased grinding media charge levels and reduced grinding media size with aim of producing a finer grind size.Northparkes implemented these recommendations along with some other changes to SAG discharge grates and the mill discharge vibrating screen. This achieved a substantial reduction in the flotation feed particle size distribution (approximately 20 microns) by utilising increased average SAG power utilisation, in turn resulting in a two per cent increase in copper recovery.With power utilisation now maximised, the next phase of optimisation has moved to the throughput-grind-recovery relationship and the cost benefit analysis of installing additional grinding power.Citation:Sulianto, Y, Trott, T, Morgan, D, Bell, T, Kock, F and Putland, B, 2016. Optimisation of Installed Mill Power Post-installation of Secondary Crushing Circuit at Northparkes Mines, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 331–338 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By N Power, R Hassell, E Jones

Wiluna Mining Corporation are progressively re-entering the old Wiluna underground mining complex. The existing underground was abandoned in 2013 by previous owners and left to flood with water levels reaching above the East Pit portal and Happy Jack Pit portal and up to 300 m below surface in the Bulletin underground. Re-entering the mine commenced in 2017 with dewatering of the Bulletin decline. The underground development had been previously supported with friction bolts, with weld mesh in places. Until mid-2021 rehabilitation requirements were based on an external visual inspection of the installed ground support scheme. However, several incidents involving falls of ground due to corroded bolts have occurred during this time, showing that this approach was inadequate. The challenge the operation faced was should the entire decline be rehabilitated, the implication being not only a large rehabilitation cost but also the impact of severe delays to the mining schedule. The question was asked can the operation better understand the level of corrosion damage and potentially optimise rehabilitation requirements. A proposal to use a systematic approach to assess corrosion by environmental condition mapping, visual external corrosion assessment, and internal corrosion assessment via borehole camera inspections was provided and accepted by Wiluna Mining Corporation. The objective of this work was to produce a three-dimensional map showing the degree of corrosion on the reinforcement systems in the capital infrastructure, this would then be used to risk assess and prioritise rehabilitation requirements. This paper summarises the approach, methodology and results that provided the Wiluna mine planning team with information to enable planning of resources and budget to justify priorities of rehabilitation.

Nov 29, 2022

British Coal has made a practical progressive approach to improving the reliability of its mining equipment. Reliability must be addressed at the specification stage but does not end there and routine procedures are used to procure equipment of adequate reliability. The techniques used to monitor and improve reliability during the operational phase of the equipment, providing engineers and operators with detailed printouts, together with the types of maintenance employed, ensure high levels of availability. Finally, the methods of repair and overhaul of British Coal equipment and systems ensure that the initial reliability targets outlined on the specification, can still be achieved.

Jan 1, 1991

China has abundant bauxite resources, but these resources are mostly of a diaspore, which has a feature of low Al2O3 to SiO2 mass ratio, typically ranging from four to six. Compared to other materials, this kind of raw materials consumes more alkaline and energy in the process of metallurgy, and incurred a high alumina production cost. To solve this problem, researchers in China have done a lot of work on removing of the silicon from bauxite. Under the impetus of these works, in 2003, the first flotation plant of diasporic bauxite in the world was constructed in Zhongzhou, Henan, China. Seven years of operating experience shows that this technology can signifi cantly reduce the costs of following-metallurgy processing. These efforts are an important reference for the processing of similar resource. In general, for Western scholars it is diffi cult to fully understand these works because most of them are published in Chinese. In this paper, a detail introduction for the research progress on China bauxite de-silica flotation was presented, these works involved crystal chemistry, wettability of bauxite minerals, collector and modifi er in bauxite fl otation and flotation practice, etc.

Sep 13, 2010

By S N. Donaldson, B L. Hollis, K Wynn, L Potts, M Evans

A real-time load-haul-dump (LHD) dispatch optimisation tool has been deployed at Panel Cave 1 and Panel Cave 2 at Newcrest’s Cadia Valley Operations. The tool, known as ORB, is the first known successful implementation of an optimisation-based, autonomous, real-time dispatch tool, custombuilt for underground mining operations. ORB can co-ordinate the optimal dispatch of LHD’s in a block cave to achieve a range of objectives while adhering to draw compliance and geotechnical constraints. It is an example of highly automated short-term interval control. This paper starts by outlining the pre-existing business planning process, detailing the simple logic that produced the daily draw order. Next, the motivations for a real-time dispatch tool are presented, drawing comparison to the limitations in existing planning processes and how these can be overcome through an optimisation-based, autonomous, real-time dispatch tool. Subsequently, the paper details the Ratio Bogging Draw Strategy, through which tonnes targets are expressed continuously on draw bells or draw points as a ratio of total cumulative cave draw. This signifies artificial planning boundaries are removed and that draw targets are linked within a cave; such that tonnes are unlocked by bogging other parts of the cave, instead of as a function of time. This creates incentive within the target mechanism for fixing and bogging struggling draw areas whilst allowing uncapped progress if all draw targets are progressing within compliance. Furthermore, the optimisation tool developed is outlined, including the data it uses and the objectives it optimises. Finally, detail on the improvements to operations the implementation of this tool has brought, and the business process change it has facilitated are presented using Newcrest’s Cadia Valley Operations as a case study.

Mar 15, 2021

A combination of the needs of business, employee desires and safety and health considerations is stimulating increasing attention to the time spent by people at work and the timing of that work. Particularly we are seeing: - innovative work schedules for 24-hour mining businesses; and - response from industry to accommodate the needs, even the desires, of employees in return for systems which are more productive and more capital efficient. There appears to be an evolutionary trend for business management to become more sophisticated and responsive to the need for achieving close to best cost work schedules to sustain continuous improvement. The underlying motivating forces driving this trend for improved techniques in organising attendance at, and time spent at work, is the seemingly inseparable combination of technological advance and ever-increasing accumulation of capital. The mining industry has not remained untouched by this thrust for ever-increasing need for best use of labour, to adopt advances in technology and to provide attractive opportunities for putting accumulated capital to work. An essential component of this on-going thrust is a substantial effort by the mining industry to improve the performance of labour by providing most-productive work schedules.

Jan 1, 1996