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Strata bolting/dowelling reinforcement techniques are being reintroduced into the mines of the National Coal Board. There are strong reasons for the selection of the full hole anchorage principle of bolting and for the development of the wood/resin dowel. There are strong reasons also for the measurement of strata bed separation as the method of assessing the effectiveness of a roof bolting system. There are several designs of bolts. Instruments have been developed for investigation and control purposes. Different drilling and bolting machines have been employed in trial sites. In addition comparative laboratory model work has been conducted on simple non-bolted and bolted systems.

Jan 1, 1971

By Cunneen R. D, Murray A. M

Exploration in the vicinity of the abandoned Mt Coolon mine has shown that the shape and attitude of the quartz lode is controlled by the interaction between the lode and a converging syncline. Gold grades within the lode are enhanced along intersections with a welded ignimbrite, and decline rapidly where the lode intersects unwelded ignimbrite. Mineralogy and textures indicate the vein has an epithermal origin modified by a later intrusive event.

Jan 1, 1989

By Weller KR

A study of high pressure rolls grinding of a number of Australian ores and minerals has been carried out using a pilot-scale machine with rolls 300 mm diameter and 70 mm wide. The results from this study have been used in conjunction with plant survey data to construct computer simulation models of various comminution circuits and these have been used to investigate options for incorporating high pressure grinding rolls into these comminution circuits. Possible rolls options for three of these circuits are presented, and likely energy savings over the existing circuits are discussed together with potential improvements in plant throughput and/or product sizing. A scale-up procedure for predicting full-scale machine performance from small-scale testing is described, and the effects of rolls operating conditions are also discussed.

Jan 1, 1991

The Argyle Diamond Mine came on stream late in 1985 as the world's largest diamond producer in terms of carat output. The design of the process plant, including the heavy medium separation (HMS) facility which provides the initial stages for separation of diamonds from gangue, evolved over a lengthy period of feasibility study and site investigation into the final form described in this paper. The commissioning was carefully planned and co-ordinated, and culminated successfully with handover of the plant on schedule and within budget. Problems encountered during .within were minimal and since then the plant has achieved greater than design throughput during its first year of operation. Darvr_ontmn

Jan 1, 1987

Saxonvale mine is a multi bench open pit coal mine developed to its Stage I capacity of 1.75 Mt/y of run of mine coal. Detailed engineering studies for the mine commenced in April 1980, approval to proceed with the development was received in July 1980 and first coal shipments were made in April 1982. The engineering and project management of the mine development was carried out by BHP Engineering. This paper outlines the design and site administration for the development and describes both the organisation structure and the control and administration procedures used by BHP Engineering to ensure that the project was Successful.

Jan 1, 1983

Discontinuities often have a very detrimental effect on the stability of mine highwall faces. The west wall of the Muja open cut is remarkable for the number and variety of discontinuity sets which occur over a relatively small area. To-date 14 separate structural domains have been identified over an area measuring approximately 560 m by 120 m.The structural domains have been grouped into four structural assemblages on the basis of their angular relationships to each other and to regional folding and faulting. The distribution of these structural assemblages appears to be erratic and no controlling factors have been identified to explain or predict them other than in the most generalised terms.

Jan 1, 1993

By Ruston R

When coal mining first commenced in Australia, the principle objective was low cost production with development directed toward recovery of 'easy' coal. Future expans- ion of these early mines into major under- ground operations was neither envisaged nor planned. As the demand for coal grew, these mines were expanded to increase output. however, the absence of initial ventilation planning brought about ad hoc systems wh;ch required continual repair and upgrading. These systems proved satisfactory in the short term because the majority of undergrouni coal mining operations were carried out at relatively shallow depths where gas emission rates were low. By comparison, coal is now being won at depths exceeding 500 metres with a corresponding increase in gas flow from the working seams and adjacent strata. The following paper addresses, firstly, the planning and institution of a ventilation system in a mine where previous inefficiencies were many, and secondly, the value of pre- planning a mine ventilation system in the early stages of mine development, and the need to continually review and upgrade the plan to account for unforeseen ^hanges.

Jan 1, 1983

After extensive testing and a period of plant trials to establish the benefits of Caro's acid (H2S05) as an alternative oxidant, Queensland Mines Limited (QML) decided to replace pyrolusite with Caro's acid in its acid leach uranium treatment plant at Nabarlek. The decision was based on the reagent savings and environmental gains associated with the removal of manganese from the process liquors, as well as the labour savings and improved oxidation reduction potential control possible in leaching using the Caro's acid system. The permanent Caro's acid generating plant was designed by Interox Chemicals Pty Ltd of Australia (IC) to suit QML's require- ments and differed from the unit used during the plant trials. Commissioning of the plant was completed in April 1983 and it has been continuously used since that date.

Jan 1, 1984

By Fukuda M, Kurita K

A mathematical model for estimating the liquid level in the hearth is presented. The analytical result was checked on a cold two-dimensional model and an additional boundary condition for the fundamental equation resulted. The applicability of the resultant equation was investigated on a cold model and a regression equation obtained for the average liquid level for Kashima No. 1 BF. Comparison of calculated and observed results were in fairly good agreement. It is concluded that the liquid level in the commercial furnace can be calculated from the measured values of pressure in the bosh and operating conditions.

Jan 1, 1975

By Sakai S, Suga S, Bisque RE

Soil gases were collected on activated charcoal, analyzed by computerized mass spectrometry and treated with multivariate statistical pattern recognition to determine the diagnostic geochemical signature associated with the Okuaizu Geothermal Field in Japan. From this a geothermal model was developed and compare to 175 "unknown" samples in a 250 m spaced grid over 30 1Qn2 mapping the areas with a matching geochemical character. Faults and fractures were generally located by the presence of high molecular weight components. Following the initial survey, the faults in two specific areas were precisely located by a second survey with samples at 10-30m spacing. Where earlier geochemical surveys had placed anomalies 1-2 Km northeast of the geothermal center, the fingerprint survey accurately mapped the system and detected several faulted zones. It was not misled by hot springs located away from the geothermal System.

Jan 1, 1987

By A Sinuhaji, H Kalangi, T B. Setyoko

Ore fragmentation at the DOZ block cave mine is highly variable, both as a function of rock type and column height of draw. Initially, the mine was constructed and equipped with limited capability to handle drawpoint oversize material. Significant issues with drawpoint availability and achieving overall mine production targets resulted. A suite of secondary sizing tools was added to the mine equipment fleet over a one-year time frame. Although significant oversize continues to be experienced, use of the correct secondary breakage tool for each particular oversize or hang-up occurrence has resulted in increased drawpoint availability, production rate, draw compliance, and operator safety. Currently, a range of secondary breakage techniques is being utilised to size material for delivery to the primary crusher. Run-of-mine material (3) is directly mucked to ore passes fitted with grizzlys that have one-metre square openings. Ore containing small boulders (>1 m3, 3) is loader-trammed to ore passes fitted with rockbreakers. Medium-sized boulders (>2 m3) accessible from the drawpoint are drilled with Sandvik Tamrock Commando drills. Boulders hung-up within the drawbell are drilled and charged with a Sandvik Tamrock Secondary Breakage Unit. Compacted, fine-grained muck is blasted utilising 55 mm cartridge powder concussion bombs.

Jan 1, 2005

Upgrading of Indonesia's Bauxite by Washing Method There were eight bauxite samples used in this research, three samples from Kijang contain total SiO2 18.36 - 29.16 per cent, Al2O3 40.12 - 48.36 per cent, Fe2O3 4.27 - 5.13 per cent, one sample from Tayan, contains total SiO2 4.69 per cent, Al2O3 38.95 per cent, and Fe2O3 19.67 per cent, and four samples from Mempawah contain total SiO2 33.5 - 44.8 per cent, Al2O3 29.8 - 35.9 per cent, Fe2O3 7.29 - 9.88 per cent. All of those bauxite ores have not fulfilled the requirement for Bayer process yet; therefore simple up-grading using a rotary drum scrubber is needed. The scrubbing process was carried out with time variable up to 60 minutes with solid percentage applied was 50 per cent and rotary speed was set up 30 rev/min. The bauxite was washed by following steps: scrubbing, screening, drying, and finally it was analysed to show chemical content. The washed bauxite produced has size fraction that is retained on the 1.7 mm of screen opening. The result of the research shows that the higher alumina content of the raw bauxite, the longer washing time is needed moreover the higher quality of the washed bauxite is produced. The highest alumina content of the washed bauxite was 53.67 per cent with the alumina recovery was 89.66 per cent and the concentration ratio of 84.80 per cent was achieved within 20 minutes of washing time of the raw bauxite (Al2O3 48.36 per cent). The washed bauxite resulted from this research is suitable as a raw material for Bayer process.

Sep 13, 2010

By R Mackay, J Brereton

On 30 June 2020, the Mine Land Rehabilitation Authority (the Authority) superseded the Latrobe Valley Mine Rehabilitation Commissioner as the independent overseer of Victoria’s declared mine rehabilitation. Currently, only the Latrobe Valley’s three brown coalmines are declared, with each mine at a different stage of rehabilitation and closure planning: Hazelwood ceased mining in 2017, Yallourn is scheduled to end mining in 2028 and Loy Yang in 2035. The three declared mines are very large, close together (Figure 1) and present significant environmental risks that must be mitigated during rehabilitation and post closure. In addition to fire risks, the brown coalmines are inherently unstable and require continuous monitoring and management of ground movements and groundwater pressures. Since 2007 several damaging events have occurred, highlighting the difficulties of achieving long-term stability, even with good landform design and rigorous ground control management plans

Aug 2, 2023

Since the days of Adam Smith and Milton Friedman the discussion of corporate citizenship and sustainability has been flooded with multiple contradictions, with proponents of sustainability saying that it is a crucial cog in the business strategy, while those against, maintain that æthe business of business is businessÆ and therefore sustainability issues are just add-ons. Sustainability arises from a deeply held vision by corporate leaders that businesses can and should play a role beyond just making money. Businesses should embrace the understanding that everything that a company does has an impact both internally and externally (communities, employees and customers), and the natural environment. This paper highlights the approach that led to a view that there is a contradiction between profitability, sustainability and community development, and we provide a further argument to the contrary. This argument is based on a comprehensive literature review of over three decades by various scholars linking corporate social performance and corporate financial performance. Driefontein Gold MineÆs approach is that of linking the community development, natural environmental and employee well-being initiatives and projects to the mineÆs business strategy. The paper further highlights the coordination and implementation mechanism of sustainability at the mine where the accountability lies with the head of the mine operations. A two pronged approach is employed where there is an internal dialogue on sustainability between the various departments coordinated by the sustainable development department and an external tri-sector partnership with local government, interested and affected parties and the mine. These approaches are closely linked to the contributions towards the mineÆs financial bottom line.

Jan 1, 2009

By Rankin W. J

Increasing concern with the emission of sulphur dioxide from smelters and roasters has caused renewed interest in processes which can use waste sulphur dioxide, such as the sulphation of nickel laterite ores. The process described here proposes to by-pass the production of sulphuric acid and react laterite directly with a sulphur dioxide containing atmosphere. A thermodynamic analysis identified operating windows in which nickel sulphate forms while iron oxide (the major impurity in most laterite ores) remains stable. The initial assumptions included unit activity of all species except nickel oxide. The lowest possible nickel oxide activity (while maintaining selectivity) increased with increasing temperature, indicating that selective sulphation is favoured by low temperatures. The temperature of interest was found to be between 500 and 800¦C. Calculations show that a feed gas containing ten per cent SO2, five per cent 02, balance N2 requires a temperature greater than 650¦C for selective sulphation of nickel. Laboratory experiments showed that the assumption of unit activity of ferric sulphate was unrealistic above about 680¦C due most likely to the formation of solid solutions which decreased the ferric sulphate activity. Results are presented which illustrate the limiting equilibrium sulphur trioxide partial pressures at 700 and 730¦C below which selective sulphation occurs. Cobalt extraction was usually between 80 and 95 per cent under conditions yielding selective sulphation, whilst nickel extraction was about 50 to 75 per cent depending on temperature and choice of upper limit of iron extraction. An operating diagram is presented for a limonite ore and shows that the optimum reaction conditions are 680¦C and an input gas containing 20 per cent SO2. Under these conditions nickel, cobalt and iron extractions are 73, 95 and two per cent respectively.

Jan 1, 1996

Whilst employed by Dyno Nobel as the Technical Services Engineer û Brisbane, I was asked, as part of a contractual agreement, to look at optimising PioneerÆs blasting process to provide the most effective rock to the new crushing and screening plant. This paper details the preliminary blast designs and practices that have been in use at the quarry and the initial changes made to these designs, and the effect they have had on the excavation and crusher performance.

Jan 1, 1999

The main aim of the conference is to work towards improved useage of steelplant slags which have largely been considered waste mater- ials, This paper summarised investigations carried out on the suitability of air cooled blast furnace slag, blast furnace granulated slag and basic oxygen steelmaking slag as road base materials. All slag samples were obtained from the PortòKembla Works of Australian-Iron and Steel Pty Ltd. Since road making materials are increas- ingly being characterised by use of resilient moduli, the compressive strengths and resilient moduli were determined for road base of the following slags. 1 Air cooled crushed blast furnace slag 2 mixes of air cooled blast furnace slag, granulated slag, and lime 3 mixes of air cooled blast furnace slag,-granulated slag and basic oxygen steelmaking slag. Evaluation of a local dacite (dense medium grained igneous rock, classification rhyolite), generally considered an excellent road base course material, was carried out for use as a reference material.

Jan 1, 1979

An assessment has been made of six reported methods for the determination of the swelling of iron ore pellets on reduction. The methods are discussed on the basis of apparatus requirements, reduction conditions, sample requirements, measurement of swelling and reproducibility. It is concluded that the CNRM, LKAB, and Lurgi methods are the most satisfactory which presently exist for determination of the swelling of industrially produced, iron ore pellets.

Jan 1, 1974

By J Pan, T Chun, D Zhu, Z Guo, J M. Young, T C. Ooi

With the rapid development of the Chinese steel industry, the strong demand for iron ores has led to huge imports of various iron ores from all over the world. As a relatively new force in the iron ore world and an important raw material supplier, Fortescue Metals Group (FMG) has achieved an annualised production rate of 100 Mt of iron ore fines. Typical blends were designed to simulate sinter blends employed in Chinese steel mills, and to determine sintering properties and metallurgical performance of blends comprising FMG Rocket fines in pilot sinter pot. It is shown that the sinter of typical blends comprising 15 - 20 per cent rocket fines possesses excellent sintering properties and metallurgical performance. With Rocket fines substitution for competitor ores in a typical customer mill blend comprising fully imported fines, the sinter productivity and tumble index increased from 1.45 t/m2h and 62.0 per cent to 1.54 t/m2h and 64.0 per cent, respectively, while attaining similar reducibility index and reduction degradation index at lower solid fuel consumption.CITATION:Zhu, D, Guo, Z, Ooi, T C, Chun, T, Pan, J and Young, J M, 2013. Sintering and metallurgical performance of blends comprising Fortescue Metals Group rocket fines, in Proceedings Iron Ore 2013 , pp 519-524 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By R Burgess-Limerick, D Lynas

A number of standards and guidance materials currently exist to assist equipment designers. The ISO process, however, is a formal process and change often lags behind technology development. In some cases, this may result in weak or ineffective standards that need to be written in general terms to accommodate future technology developments, meaning some standards may only establish minimum requirements and not be overly helpful to equipment designers, in particular when designing for workforce diversity and inclusivity. By contrast, advisory information as issued by various mining regulatory bodies is able to respond more quickly to changes in technology. Standards do however have a safety and productivity focus providing design consistency between equipment manufacturers, a basis for auditing purposes, assistance in mining regulation and compliance, and in the development and application of safety management systems. As an example of challenges facing equipment designers, ISO3411 (2020) provides data approximating the 5th, 50th and 95th percentile of the ‘earth-moving machinery operator population’ for numerous static dimensions relevant to the design of earth-moving equipment. These data are then utilised in ISO6682 (2020) to provide recommendations regarding the location of controls. Attempting to utilise the data provided in ISO3411 (or other sources of static anthropometric data) creates further challenges for equipment designers, in that reference percentiles is problematic for design purposes. There is no ‘5th or 95th percentile operator’ as individuals vary along each dimension (Robinette and Hudson, 2006). Although dimensions have some degrees of correlation, when multiple dimensions are considered, the range of individuals which fall within a given range on all dimensions reduces substantially. For example, only about 82 per cent of individuals in a population will fall within the 5th to 95th percentile ranges for both height and weight. The more dimensions are considered, the smaller the range of people who actually ‘fit’ the description.

Apr 16, 2024