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By J G Bastias

It is sometimes necessary to resort to extremes in order to call attention to something that is pertinent to safety in mining. When some of the experts in occupational safety talk about this topic, they usually refer to a 'regulation' established by the Romans which stated that, due to the health hazards, usually death, no Romans but only slaves should work in mining. Since the time of the Roman Empire, a lot of ground has been covered in the field of mine safety. Nowadays, it can be said that occupational safety is being seriously addressed, with the result that the number of mining accidents has reduced dramatically, fatalities in this industry are less frequent, and the rate of accidents compared with other activities, such as construction or fanning, is low. This achievement has been possible initially through government legislation and by procedures established by the mining companies themselves. However, the dilemma for government is whether to regulate and if so, how much. It is pleasing to observe that most companies are establishing working procedures which conform with new government legislation, placing strong emphasis on the duty of care for mine employees. There will always be some regulatory aspects of legislation, and perhaps the best example of this is in the use of mine hoists where there are no international or Australian standards, and the regulations applied are of an empirical nature that err on the side of safety.

Jan 1, 1994

An intensive safety campaign at Mount Isa Mines Limited from 1956 to 1966 saw the lost time accident frequency rate fall to half its original level. A review of the safety programme was carried out in 1967 and in 1968 the Five Point Safety System was introduced. The seven years since its introduction have been years of significant achievement both in production and safety. Improving safety is a fundamental part of Mount Isa Mines Limited's policy and this system has been a major tool in implementing that policy. To be successful personnel need to be prepared and trained for its introduction and subsequently counselled on its use. A carefully prepared programme is required to phase in various aspects of the system and to make use of complementary steps. The system has been a success and it is anticipated that the continued drive to improve the use of principles of the system will further improve safety. It is hoped that this paper will be of value to those personnel concerned with industrial safety in Australia.

Jan 1, 1975

The Prominent Hill copper-gold deposit is located approximately 150 km north west of Olympic Dam, on the southern margin of the Mount Woods Inlier in South Australia. Its discovery in November 2001 resulted from the application of a geological model developed from geological, geophysical and petrophysical data pertaining to the Olympic Dam deposit. The discovery has dispelled the notion the Olympic Dam may be unique, and that another deposit like it is unlikely to be found. The Prominent Hill mineralisation is hosted by haematite-matrix hydrothermal breccias, which have suffered extensive iron-sericite-silica alteration and overprinting. Copper, gold, barium, fluorine, uranium, cerium and lanthanum are all intrinsically associated with the hydrothermal iron. Breccias intrude an east-west striking, fault-controlled sedimentary succession, which is flanked to both the south and north by volcanic complexes. Many similarities between Prominent Hill and Olympic Dam are documented including geological setting, mineralogy, breccia styles, and alteration. Differences relate largely to the nature of the immediate host rocks. The similarities and difference provide key data for improving exploration models for this style of iron oxide copper-gold deposit, both within the Gawler Craton as well as globally.

Jan 1, 2004

At Pasminco Mining's South concentrator. which was commissioned in 1952. an expansion. modernisation and efficiency improvement program commenced in 1986 with a coarse ore stockpile and grinding circuit expansion. the replacement of small flotation cells and the upgrading of reagent mixing and metering equipment. The program continued with the installation of a TDC 3000 based process control system (1988) and concentrate thickeners (1990). By mid-1991 a further grinding expansion and the installation of zinc flotation feed regrind ball mills and zinc recleaner column cells will be complete. leaving the use of ceramic disc fillers and development of process control strategies as probably the remaining major avenues for improved process efficiency at present.

Jan 1, 1991

The occurence of high silver values in the oxidised zone of the main lode at Broken Hill is well known as a large factor in achieving the early fame of Broken Hill, and the minerals of this zone form a long list, which has been tabulated by G Smith*, and includes...

Jan 1, 1926

By R G. Reddy, Z Zhang

Viscosities of CaO-aluminosilicate ternary melts were estimated using a structure-based model. The model considers depolymerisation effects and related breakdown of the silicate network structure on the addition of metal oxides to the melts. The predicted values are in good agreement with the experimental values over the whole temperature and composition range.

Aug 21, 2024

By E Donskoi

In order to develop downstream processing routines for iron ore and to understand the behaviour of the ore during such processing, extensive mineralogical characterisation is required. To determine mineral associations, mineral liberation and grain size distribution, imaging techniques have to be used. There are two main imaging techniques used for the characterisation of iron ore, ie, Optical Image Analysis (OIA) and Scanning Electron Microscopy (SEM). In this article a QEMSCANTM system is used as an example of SEM methodology and results obtained from it are compared against results obtained by the CSIRO ‘Recognition3/Mineral3’ OIA system.Both OIA and QEMSCANTM systems have advantages and drawbacks. Even though the latest QEMSCANTM systems can distinguish between major iron oxides and oxyhydroxides, it is still problematic for QEMSCANTM to distinguish between iron ore minerals very close in oxygen content, eg haematite and hydroheamatite, or between different types of vitreous goethite.QEMSCANTM also can misidentify minerals with close chemical composition, ie haematite as magnetite and vitreous goethite as haematite. In OIA, iron minerals with slight differences in their oxidation or hydration state are more easily and directly recognisable by correlation with their reflectivity. In both methods, the presence of microporosity can result in some misidentification, but in SEM methods misidentifi cations due to microporosity can be critical. Low resolution during QEMSCANTM analysis can significantly affect the textural classifi cation of particle sections.The main conclusion of this study is that, for low iron content ores or tailings, QEMSCANTM can provide much more detailed information on the gangue minerals than OIA. However, for routine characterisation of iron ores with high iron content and containing a variety of iron oxides and oxyhydroxides, OIA is a faster, more cost-effective and more reliable method of iron ore characterisation. A combined approach using both techniques will provide the most detailed understanding of iron ore samples being characterised.

Jul 11, 2011

The paper describes the 209 in. single stage axial flow mine ventilating fan which commenced operation at The Zinc Corporation Limited, Broken'Hill, N.S.W., in January, 1954.This fan is used to ,ventilate the underground workings of The Zinc Corporation Limited and New Broken Hill Consolidated Limited and, at the time of installation it was the largest fan of its type in the world. It has amaximum capacity of 900,000 c.f.m. at 4·2 in. watergauge and is equipped with adjustable pitch blades and a novel form of variable speed drive.The considerations which lead to the adoption of this particular design are outlined, and a full description of the contruction and installation of the fan and auxiliaries is given.Comprehensive acceptance tests were carried out on the completed installation and, the testing procedure is described in detail. The results of sound level measurements are also included. A brief report on the performance during the 12 month period from 1st July, 1954, to 30th June, 1955, is then given.SELECTION AND DESIGN OF FANGeneral ConsiderationsBecause of the economic advantages of joint ventilation of the underground workings of The Zinc Corporation Limited and New Broken Hill Consolidated Limited, it was decided, after a full review of the future ventilating requirements of both mines, to sink a 20 ft. diameter circular upcast airway on the common boundary of the two properties, to handle a maximum quantity of 900,000 c.f.m.The anticipated air requirements were at this stage estimated to be:(a) initially 700,000 c.f.m. through a mine equivalent orifice of 160 to 2'40 sq. ft. (equivalent total pressures being 2·70 in. w.g. and 1·20 in. w.g.) ;

Jan 1, 1956

By Lock PR

The Silver Swan nickel mine is located at the Black Swan Nickel Project, 53 kin north east of Kalgoorlie, Western Australia. The Silver Swan orebody is a massive sulphide nickel deposit dipping 70¦ east with an average in situ grade of 14 per cent. Mining of the massive orebody is by Mechanised Ramp Cut and Fill (MRCF). A mining recovery of 98 per cent and minimising dilution are primary goals in extracting the high-grade ore. Placing a distinguishable marker bed (working platform) on rock fill was identified as a key method to achieving these goals. Gravel from a pit located onsite was considered the most suitable material for the marker beds. Research undertaken to design the marker beds using the gravel revealed conventional methods used in mining would not suffice, but that road stabilisation methods could be a viable alternative. Trials used a road recycler to mix cement and gravel in situ and several test beds were constructed on the surface to determine the final design. The trials attempted to replicate a marker bed's life cycle of construction and placement and mucking of ore from the marker bed.

Jan 1, 1998

By C Samuelsson, Q Shu, A Lennartsson, F Gyakwaa, A Andersson, J Isaksson

The physico-chemical property, viscosity, is essential for pyrometallurgical processes and influences the settling rate of valuable metal droplets in slag, affecting the metal recovery. The copper slag from smelting furnaces typically contains between 1 and 2 wt per cent Cu, which equals to or is higher than in most sulfidic copper ores mined today, meaning the slag is a valuable resource for copper extraction. A low viscosity is desirable for slag-cleaning through a settling furnace where entrained droplets settle under gravity. One approach to control the viscosity is through the slag composition. The literature has limited data on the correlation between viscosity, slag structure, and optical basicity of iron silicate slag with FeO/SiO2, CaO, and Al2O3 as factors. Therefore, the present study evaluated the influence of these factors on viscosity and correlations with slag structure and optical basicity. The FeO/SiO2 ratio (at%/at%) and the CaO and Al2O3 content were altered in two levels, resulting in a two-level full factorial design with three factors. The study was done by synthesising FeO–SiO2–Al2O3–CaO–MgO–Cr2O3 melts, followed by water granulation. The melt structure of the samples was analysed with the help of Raman Spectroscopy. The viscosity was then estimated with a high-temperature rheometer using a Mo spindle and crucible. The results showed a correlation between the optical basicity, FeO/SiO2 ratio, and viscosity, where a high optical basicity and FeO/SiO2 ratio were beneficial for achieving a low melt viscosity.

Jun 19, 2024

Mr Chairperson, respected leaders of the mining industry, ladies and gentlemen;   Good morning, Kiora, Nihao.   I am very honoured to give a speech to the 2005 New Zealand minerals conference. I would like to take this opportunity to express my sincere thanks to the Ministry of Economic Development to invite me to be part of this important event.   Today, I am going to talk about two themes: a brief introduction of ChinaÆs economic development, including ChinaÆs energy strategy; the good bilateral relations between China and New Zealand, its potential for further development and its relevance to our cooperation in the field of minerals and energy.   It is a well-known story that over the past 27 years, great changes have taken place in China. In 1978 when ChinaÆs reform and opening up just started, its gdp was near to only 150 billion usd dollars. By the year of 2004 it reached to 1.6 trillion usd, an average of yearly growth rate 9.4 per cent.   ChinaÆs great achievements are widely appreciated both in China and abroad. ChinaÆs development has not only improved the living standard of its own people, but also produced a huge market and brought about great opportunities for the world. Since ChinaÆs entry into WTO in 2001, China has imported near to 1.8 trillion usd dollars of goods, averaging a yearly imports of 500 billion usd dollars, creating for other countries and regions more than ten million jobs.   Our prediction is that in the next five years, ChinaÆs imports will be well over three trillion usd dollars. China will continue to serve as one of the leading growth engines for the future world economic development. Now China is on its great strive to achieve the goals of improving living standard for all the Chinese people. We are trying to reach a quadruple gdp of 2000 by the year of 2020, namely to reach gdp four trillion usd, a gdp per capita 3000 usd dollars.

Jan 1, 2005

The Elura Orebody consists of a number of parallel, vertically oriented pipe-like structures of pyrite-sphalerite-galena mineralization located at the core of a structural dome. Concentric zoning of the mineralization into an outer Siliceous, intermediate Pyritic and inner Pyrrhotitic Zone has been previously recognized and is used in routine geologic modelling of the lead, zinc and silver grades.Statistical analysis of the metal grade distribution in the orebody has confirmed the importance of the mineralogical zones in the understanding of grade trends. The gradational nature of intra-zone boundaries, especially those related to the subjective definition of the Siliceous Zone, are apparent in the statistics.

Jan 1, 1990

By Yanske TR, Lane WL

The Doc Run Company and its predecessors have been mining for over 130 years utilising the room and pillar mining method. This method has left approximately 20 per cent of the orebody in the remaining pillars. The original design and planning for the mines did not include extensive pillar extraction. This paper summarises the introduction of the pillar extraction and backfill techniques which have been implemented since 1991. These techniques include the use of low cost fill walls up to 20 in in height and the use of stinger trucks for topping off the fill. In conjunction with these accomplishments, much experience and confidence has been gained in the use of numerical modelling as a method of predicting pillar stability as the mining of pillars progresses. These advances have led to pillar extraction hecoming a major portion of the overall production and have added to the mine life of Doe Run's six operating mines.

Jan 1, 1998

By M Ahmed

Reliable face support pressure is necessary for shield driven tunnels in cohesionless soils to prevent excessive ground movements. This paper presents experimental work on stability of a tunnel face using transparent soil models aiming to obtain magnitude of tunnel face minimum supporting pressure, failure pattern and extension of failed zone. A model tunnel was preinstalled in transparent soil which was supported at the face by means of water pressure. Tests were performed by reducing supporting pressure until collapse occurred. Model tests were sliced optically with laser sheet and images were captured for every decrement in tunnel supporting pressure. Later, these images were analysed by digital image correlation (DIC) and vector fi elds of incremental displacements were obtained. Values of minimum support pressures were given for different cover/diameter (C/D) ratios. Geometry of the failure zones depicted for different (C/D) values and appeared to be of chimney shape with a limited extension front of the face. A minimum support pressure was achieved with support pressures as low as 10 ± 1 per cent of the effective vertical stress at the tunnel axis. The stability of the tunnel face was related to the coefficient of active earth pressure with C/D ratio having a small effect on the magnitude of required pressure at collapse. In general, results of the study were in agreement with current knowledge of full-scale situations.

Mar 8, 2011

By G Hancock, J Lowry, T Coulthard, W Erskine, M Saynor

An important part of planning for the rehabilitation of uranium mine sites is the ability to assess the geomorphic stability of the final landform, over time frames ranging from decades to millenia. Depending on the environmental conditions, erosion features such as gullies may incise into containment structures, potentially leading to the exposure and transport of encapsulated radioactive material. Further, erosion may lead to increased sediment loads and the transport of other mine-related contaminants off-site and into downstream waterways. While erosion may be monitored and assessed over the short term (years to decades), the longer-term behaviour (centuries to millennia) of such landscapes is not within any meaningful human management time frame. Landscape evolution models (LEMs) can provide information on soil erosion rates at decadal or centennial scales over large spatial scales, and evaluate the sensitivity of these processes to environmental changes. However, an important issue associated with the use of models is the ability to assess the reliability and accuracy of the model. In this paper, the CAESAR-Lisflood LEM is tested for its ability to predict soil erosion from a series of 30 m × 30 m experimental plots specifically constructed for this purpose on a trial rehabilitated landform at the Ranger Uranium Mine in the Northern Territory, Australia. Model predictions of bedload and suspended sediment loads from the erosion plots were compared with field measured observations collected over four wet seasons from the trial landform. Once calibrated for the specific site hydrological conditions, the predicted sediment yield – specifically, bedload – demonstrated an excellent correspondence with the field data. However, longer-term simulations of ten years identified an exhaustion effect in sediment yield from the landform. These latter results indicate that a weathering function needs to be incorporated into CAESAR-Lisflood to ensure confidence that the CAESAR-Lisflood LEM will be able to correctly predict the long-term evolution of a rehabilitated landform once it has been?constructed.CITATION:Lowry, J,?Saynor, M,?Erskine, W, Coulthard, T and Hancock, G, 2014. A multi-year assessment of landform evolution model predictions for a trial rehabilitated landform, in Proceedings Life-of-Mine 2014 , pp 67–80 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By K B. Quast

During the prefeasibility stage of the mining cycle for a gold deposit, an evaluation of the ore leaching characteristics from various defined areas is essential prior to plant design. There are a number of simple laboratory tests which have proven successful in establishing gold and silver leaching kinetics, carbon adsorption and fouling, as well as elution characteristics. A number of case studies of carbon-in-pulp (CIP) simulation are presented which show excellent agreement between calculated and assayed gold and silver grades in feed and adsorbed on carbon which validate the methods used.

Jan 1, 1998

Coal washing practice can be improved not only by critical examination of the plant being operated but also by studying plants operated in other areas. The developments at the Australian Iron & Steel Pty. Ltd. plants are discussed in relation to experiences there as well as developments which have taken place in Queensland in recent years. Early A.I.S. problems involved small coal cleaning in heavy medium cyclones and flotation. A proposed future plant flowsheet for A.I.S. is considered in the light of these experiences. Reference is made to plants operated by the Thiess, Peabody, Mitsui Coal Company Pty. Ltd. at Moura and the Utah Development Company's plants at Blackwater and Goonyella in the development of coal washing prac- tice in Australia.

Jan 1, 1975

By Drury SA, Williams RD, Nind DC

The Airborne Thematic Mapper is an eleven channel digital scanner which acquires image data in the visible, near infra-red, short wave infra-red and thermal infra-red wave- lengths. A description of the system is presented which includes details of the operating wavelengths and performance parameters of the scanner. Consideration is also given to the aircraft installation requirements. During January 1984 the scanner surveyed the mineral rich areas of Leonora, Laverton and Kalgoorlie in Western Australia. This is a region of intense exploration activity for gold and base metals. Some 30,000 square kilometres were systematically surveyed in a period of ten days. This scanner was flown at 7,000 metres altitude giving a ground pixel size of 17.5 by 17.5 metres. The flight line spacing was 8 kilometres. The overall project took some thirty days from conception to completion. The planning and execution of this operation are described in detail. The resulting magnetic tapes provided 11 channels of digital image data over a 30,000 square kilometre area and a variety of image processing techniques were employed in order to capitalise fully on the results. The imagery provides a powerful tool for the geological mapping of the terrain. The data can also be used to monitor the environmental effects of mining operations.

Jan 1, 1986

By Chitombo G. P, Thompson A. G

Excavation engineering involves three key design processes; excavation design, blast design and reinforcement design. An excavation engineering methodology is proposed in an attempt to promote integration and simultaneous consideration of these three design processes. This methodology requires research and development of, inter alia, a universal rock mass classification system and a universal data display system. Simple examples are used to explain and illustrate the concepts central to these components in the three design processes.

Jan 1, 1995

By M W. N Buxton, M S. Shishvan, J Benndorf

The flow of information, and consequently the decision-making along the chain of mining from exploration to beneficiation, typically occurs in a discontinuous fashion over long timespans. In addition, due to the uncertain nature of the knowledge about deposits and the inherent spatial distribution of material characteristics, actual production performance in terms of produced ore grades and quantity and extraction process efficiency often deviate from expectations. Reconciliation exercises to adjust mineral reserve models and planning assumptions are performed with timely lags of weeks, months or even years.With the development of modern information and communication technology over the last decade, a flood of data about different aspects of the production process is available in a real-time manner. For example, sensor technology enables online characterisation of geochemical, mineralogical and physical material characteristics on conveyor belts or at working faces. The ability to utilise this additional information and feed it back into reserve block models and planning assumptions opens up new opportunities to continuously control the decisions made in production planning to increase resource recovery and process efficiency. This leads to a change in paradigm from a discontinuous method to near real-time reserve reconciliation and model updating, which calls for suitable modelling and optimisation methodologies to quantify prior knowledge in the reserve model, process and integrate information from different sensor sources, back propagate the gain in information into reserve models and efficiently optimise operational decisions in real-time.This paper introduces the concept of an integrated closed-loop framework for real-time reserve management, incorporating sensor-based material characterisation, geostatistical modelling under uncertainty, modern data assimilation methods for sequential model updating and mining system simulation and optimisation. The effectiveness of the framework and the value added will be demonstrated in an illustrative case study.CITATION:Benndorf, J, Buxton, M W N and Shishvan, M S, 2014. Sensor-based real-time resource model reconciliation for improved mine production control – a conceptual framework, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 223–234 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014