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By M Khanal, J Qin, B Shen, Y Duan, X Luo

Gaining confidence in interpreting rock and strata properties of the coalmine roof is necessary for design, maintenance, modelling and optimisation of roadways supports. One of the key causes of roadway instabilities experienced in underground coalmines is an extreme variable nature (thickness, competence, discontinuities etc) of the coalmine roof. Normally, the thickness and strength of the roof are characterised with the geotechnical and geological data gathered from exploration boreholes, which are drilled often at considerable distances apart. This limited data cannot capture localised geological variations in the coalmine roof. With this background, this paper explores feasibility of using measurement while drilling concept to perform geotechnical characterisation of the coalmine roof. The parameters, for example, penetration rate, rotary speed, torque, sound, vibration, obtained during the drilling process can provide valuable insights into geotechnical properties. The paper describes the progress of the experimental work conducted at the laboratory on synthesized concrete samples representing various rock strata using a field-scale drilling machine. The samples with and without interfaces have been tested to replicate various underground roof strata. The signals returned from the drill machine, as the drill bit passes through the layers, have been analysed and interpreted to characterise whether the drill response data can differentiate various strengths associated with the rock layers. The initial laboratory results are promising as they show distinct responses of the various sample blocks in a controlled environment. The drilling data can differentiate the synthesized rock samples and detect ‘signatures’ of the roof strength variability and delineation of lithological interfaces (transitions). The weight and torque on the bit vary and show dependency on the strength of the blocks.

Nov 29, 2022

Wire rope, when used for hoisting on a mine is the weak- est and most vulnerable unit in the most expensive'-group of installations or! the mine. With the introduction' of hoisting on the S1Koepe"' sheave, a new technique was-established. This innovation brought with it the certain- advantages which long had been recognised and which are being developed further. For many years, drum winders of many types had been the sole means by which ore had been hauled from mines. This type of winder, with its capacity for rope storage on the drum, permitted mine operating personnel to cut short lengths from

Jan 1, 1964

By Reid A. F

Since early 1971 Western Titanium N.L. has been operating an ilmenite upgrading plant on a commercial basis at Capel, Western Australia. In their process ilmenite is pre- oxidized, then reduced in a rotary kiln to a mixture of metallic iron and titanium oxides. The iron is leached out by accelerated rusting in aerated water, leaving a product with titanium content, expressed as Ti02, of about 92%. Samples from different stages of the up- grading process, representing operations over the last two years, have been studied in detail by X-ray diffraction methods, and the sequences of phases and reactions occurring have been determined. Quantitative X-ray studies showed the ilmenite feed materials to consist of a mixture of ilmenite and pseudo- rutile. Pre-oxidation of the ilmenite at =1000¦C leads to the formation of rutile plus a Fe2TiO5-FeTi205-Mn2TiO5 solid solution. The final reduction product consisted of a mixture of metallic iron, reduced rutile and a FeTi05-MnTi205-Ti305 solid solution. The relative amounts of these reduction products were very sensitive to the initial concentra- tions of the minor constituents manganese and magnesium. The effects of variation of ilmenite feed rate, reducing atmosphere,- reduction temperature and controlled addition of magnesium were also studied.

Jan 1, 1973

By Tomlinson E, Lama RD

Drainage of gas has been practiced overseas for almost half a century. Peal advances in drainage of gas to combat high emissions became practicable in the late fifties and early sixties when the technology was standardised to use it under a variety of mining and geological conditions. Today methane drainage is practiced in the United Kingdom, Germany, France, Belgium, Poland, Czechoslovakia, Hungary, Ibmania, U.S.S.R., China, Japan, Canada, U.S.A. and Mexico. Australia entered the list of countries using gas drainage on 3rd March, 1980 when the first full scale gas drainage system was set up and commissioned at West Cliff Colliery to drain gas from the Bulli Seam. Methods used in Europe are different from those used in North America, Japan and Australia mainly because of the different mining methods and also because of the limited number of seams under extraction, relatively new coal fields, and comparatively larger distance between the seams. In spite of the difference in the technique, the basic aim is the same and that is to improve ventilation and reduce ventilation costs, alleviate dangerous gas accummulation, overcome outburst hazards and ultimately make mining safer and more efficient. Over the last decade, there has

Jan 1, 1982

Circuit alterations and adoption of more compact items of equipment have made it possible to increase the capacity of the King Island Scheelite concentrator, both with regard to head grade and feed tonnage, while at the same time increasing total recovery and reducing maintenance costs. The present operation is described, with particular emphasis being placed on alterations made during the last two years to achieve capacity Goals.

Jan 1, 1977

Preparing for automated sample preparation has two facets; the need for better procedures as seen by the laboratory Manager and the approach to be adopted as envisaged by the equipment manufacturer. Both have many options and during the 1990s some at least of these options will be tried. As automation of sample preparation is only just beginning, can it be said that there is a real need for better procedures. What does automated sample preparation have to offer? Does it have real advantages or is it just a marketing tool to sell equipment?

Jan 1, 1976

During the past seven years silver recovery has been increased from 9 per cent to over 61 per cent. The changes in plant practiee which have led to this increase are described. Gold room clean-up procedure has been varied, so that half the additional silver is obtained as pure silver chloride, which.is converted to silver bullion for marketing.

Jan 1, 1964

By Hutton W, Jack G. St

The Argyle Diamond Mines process plant incorporates a high level of computerised process control, and facilitates detailed performance monitoring. The control system was designed to provide a high degree of plant automation and a good quality interface to operators and management which includes control, data logging, graphics displays and detailed reporting. Performance monitoring techniques, both on-line and off-line have been developed to ensure circuit performance is optimised with particular emphasis on minimising diamond losses.

Jan 1, 1987

By N Steenkamp, L Furstenberg, W Cele, M Richter

Managing productivity and improving efficiency for a healthy return on capital employed have become key mining industry strategies under prevailing tough global market conditions. However, achieving this in a multisystem environment such as a mining operation can be daunting. The field of discrete event simulation offers some relief, giving engineering teams insight into multivariable systems and stochastic processes. It allows for integrated system thinking and domain expertise to be woven into project thinking fibre. Directed system optimisation and therefore improved efficiency becomes possible. Furthermore, capital discipline accrues from optimal upgrade investments. This paper illustrates the practical application of this approach by reviewing a typical case study for a direct shipping iron ore operation. Dynamic simulation was used to establish maximum processing plant capacity under varying material characteristics and identify capital-efficient upgrades for increasing production.The study started with descriptive statistical analysis of existing data. Discrete equipment and system capacities were defined, followed by static plant mass balance calculations to establish bottlenecks and overall static capacity. Equipment ‘uptime’ and ‘downtime’ analyses established system and overall plant availability and utilisation. From this information, a dynamic simulation model could then be developed and initially calibrated against actual plant performance to verify its robustness. Once confirmed to accurately represent existing plant dynamics, system capacity response to variable changes could be tested to ultimately determine maximum plant capacity. Additionally, plant optimisation was incorporated to arrive at optimal upgrade points. Maximum capacity and necessary upgrades were established as a function primarily of feed size distribution. Additionally, the interfacing effects of rehandling feed material to the final product grade and potentially to life-of-mine were established as important outcomes. The results of the study illustrate the value of using dynamic simulation models to realistically and cost-effectively increase throughput.CITATION:Cele, W, Furstenberg, L, Richter, M and Steenkamp, N, 2015. Capacity evaluation of iron ore processing facilities utilising dynamic simulations, in Proceedings Iron Ore 2015, pp 597–604 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Chen J, Sun ZY

The present paper gives the design of a new HGMS for magnetic separation of sulphides. The main characteristics of this HGMS are using iron-cladding saddle-shaped magnetic coil for instead of the ordinary magnet, and combining reciprocal-linear motion with vibration to actuate the separation box, and the magnetic field intensity is high up to 2T as well. For improving the magnet system design, a modified finite element method is used to calculate the distribution of magnetic field intensity of separation space of the magnetic coil, and accordingly the calculation results the magnetic leakage coefficient can be determined easily, thus designers apart from the empirical way. KEYWORDS: HGMS, reciprocal motion and vibration, finte element method, saddle-shaped coil.

Jan 1, 1993

This paper will examine some of the significant developments in the training field in Australia in the past decade and the application of these changes to the mining industry generally, and the coal sector specifically. Three major aspects will be examined:1. Competency - the use of Industry Competency Standards and how these can be used for achieving enterprise performance requirements2. Assessment - making judgements about an individual's competence, and using a rigorous assessment system as the basis for the "authorisation" system at a mine3. Evaluation - ways to evaluate the return on investment in training, and convincing CEO's/shareholders that your training dollar is being spent wisely.Before examining these issues, it is important to understand the drivers of change in the training systems in Australia, and the functions that Industry Training Advisory Bodies (ITABs) perform.

Jan 1, 1998

Wrenching between basement blocks is considered to be the mechanism whereby a well developed set of en echelon folds and an associated fracture system are developed in the Fitzroy Depression, Western Australia. The regular geometry of these structures accords with a right lateral regional coupling between high-standing, basement blocks bounding a trough filled with a thick pile of stratified Phanerozoic sediments. The structures developed during or after the Mesozoic Era, but the couple is inferred to have been applied to blocks outlined by old lineaments, which may reflect strains or ruptures in basement that developed during the Precambrian, and which were regenerated during Palaeozoic and Mesozoic time.

Jan 1, 1967

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

Geochemical investigations carried out in the Woodcutters area, Rum Jungle district, NT., consisted of a programme of C-horizon soil geochemical sampling followed by rotary-percussion and diamond drilling.Comparison of detailed geochemical sampling with the original broadly-spaced sampling showed that the structures along which the orebodies occur are reflected very closely by the detailed sampling.A series of vertical rotary-percussion drill holes put down adjacent to a gossan revealed a broad layered dispersion of lead and zinc in the deep lateritic weathering profile, while primary dispersion haloes are only very narrow. The layering appears to be related to the weathering profile.

Jan 1, 1978

The effect of temperature, time and SO2 concentration in the atmosphate have been studied for a complex Pb-Zn concentrate, which contained four sulphides and some organic material, in order to determine optimum roasting conditions. Under static roasting conditions virtually complete sulphation was achieved after roasting at 650¦C.2 hours in 10% SO2 in air. Both zinc ferrite and zinc silicate were observed to form early in the roasting, but continued exposure to SO2 -containing gases caused decomposition of these as the roasting time increased. Water and acid solubilities of iron, silica, calcium, magnesium and aluminium in the calcine were determined, as a function of roasting time, temperature and atmosphere composition.

Jan 1, 1970

The port of Townsville is situated on the main north/south rail system of the Queens- land Government Railways and is the eastern terminus of the east/west rail link from Towns- ville to Mount Isa. With a stable beef and wool producing area along the east/west rail route, the expanding mineral industry development at its western end and the continuing growth of the Townsville region the administrators of the port are continually'keeping abreast and ahead of port development to ensure an effective and economic growth of port facilities to meet the needs of the area served by Townsville.

Jan 1, 1974

By Williams RJ

This paper presents an overview of the design and development , application to date and potential of a real-time return gas monitoring system.Initially developed as an ACARP/Industry funded project, whose prime aim was to create a `turn-key', prototype, stand alone, real-time, Return Gas Monitoring System (RGMS) capable of providing quantitative assessments of gassiness levels on a shift by shift basis, enabling unusual gas emission patterns to be readily flagged.

Jan 1, 1998

By S Strohmayr, R Harvey, A See

Ernest Henry Mining Pty Ltd started production in August 1997. The Ernest Henry orebody consists of two distinct parts, a complex supergene ore zone overlying a primary ore zone. The economic copper minerals in the supergene ore were chalcocite, bornite, secondary chalcopyrite and native copper while the primary zone has only chalcopyrite. The variability of the supergene zone made concentrator operation difficult and predicting metallurgical performance using mineralogy essential to establish the capabilities of the concentrator. A paper presented at the 1998 Mine to Mill Conference entitled Mineralogy Controlling Metallurgy at Ernest Henry Mining (Barnes, Strohmayr, Brindley and Munro, 1998) presented the testwork and initial plant surveys that showed that the mineralogy of the ore controls the metallurgy of the concentrator. This paper presents the data obtained from the subsequent years of operation treating both the supergene and primary ore types. A review of the actual supergene mineral distribution in feed and subsequent recoveries compared to those predicted as part of the flowsheet design is also presented.

Jan 1, 2003

By Y Potvin

Underground mines in Australia are progressively operating at greater depth, sometimes in conditions where mine induced stresses are very high. In such conditions, the seismic activity often becomes intense and violent and in response, mines must develop and implement a sound rock burst risk management strategy to continue operating safely.This paper discusses the latest techniques successfully used in Australian mines to mitigate the risk of rock bursts. In particular, the paper describes how the analysis of data collected from seismic monitoring systems can provide an understanding of the seismicity and be used for quantifying seismic hazards in the mine. Once an adequate understanding and assessment of seismic hazard has been achieved, the associated risk can be mitigated using different layers of protection.Strategically, modifying the mining method, the extraction sequence and/or the mining layout can alleviate the seismic hazard, but these solutions generally cannot be implemented rapidly. In the short-term, seismic risk can be mitigated tactically using an energy absorbing support system or to remove personnel from being exposed to rock burst damage by implementing exclusion zones.

Mar 21, 2011

By N J. Betts

This paper aims to build on the strong emphasis that was placed on safety in the Sydney AITES-ITA Congress in March 2002. It will do this by comparing safety records from some major tunnelling projects in Europe and Australia over a period commencing in the second half of the 19th century to the second half of the 20th century and examining reasons for the apparent marked improvement that appeared in the 1980s. Further by looking at the relationship between this improvement and current trends in the australian industry by means of a detailed review of the safety record for the Northside Storage Tunnel project in Sydney which was completed in mid-2000. The paper will conclude by providing a summary of the progressive approach adopted by the minerals industry in australia and summarising the current state of tunnelling and underground construction in australia with respect to recently completed projects and potential major initiatives.

Jan 1, 2003