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By Ellson I. G

Shay Gap was created for the sincrular purpose of housing, in comfort, the workforce that would be required to mine iron ore, from leases held by Goldsworthy Mining Limited, in hill country, approximately 170 kilometres east of Port Hedland in the Pilbara region of Western Australia. To combat the and environment, the Company ultimately decided to adopt a novel planning concept for the town, which had not been attempted before in Western Australia. The special problems encountered during planning, and the reservations that were expressed during construction and early settle ment, are now part of the dim past. During the three years of occupation now achieved, there has been accumulated a story of success in the provision of an acceptable alternative to modern suburbia. Not only may this be claimed, but it can also be argued that the Shay Gap concept has been a more successful solution to a real environmental problem in our arid Pilbara region than has been seen in other similar settlements.

Jan 1, 1976

In engineering applications of explosives for rock breaking, the released energy is expended mainly into heat, rock crushing and fracturing, seismic waves, air blast, and noise. Those parts of energy which pass into seismic waves and air wave create environmental problems since they are transmitted away from the blast site. In order to predict the environmental effects accurately, one must be able to predict the energy distribution at the source. The energy distribution at the source is significantly controlled by the blast constriction. Consequently, the accuracy of prediction and control of ground vibrations generated by blasting is affected by various matrices of blasting constriction.

Jan 1, 1986

By K Hines

Anglo Platinum is the worldÆs largest producer of platinum group metals, and also produces large quantities of nickel, copper and cobalt at its Refining complex in Rustenburg, South Africa. In 1995 Anglo Platinum embarked on a smelter modernisation project, primarily to reduce site emissions to below the guideline limit of 20 tonnes per day SO2, but also to increase the converting capacity in line with future projected production profiles. To achieve these requirements the existing Pierce Smith converters were replaced with a single large Ausmelt converter and a new acid plant. This was the first time that an Ausmelt furnace had been used for converting, but it had the advantages of being a very robust furnace and was fully enclosed, giving good gas capture. It was thus considered the most appropriate technology from both a process and an environmental perspective. It also enabled the smelting and converting furnaces to be decoupled. The plant was commissioned from late 2001 and the first tap was in June 2002. Despite being a new technology, ramp-up has been similar to other large scale pyrometallurgical operations. Numerous process improvements have been made since start-up, most notably a change from two-stage batch to fully continuous, resulting in the plant now operating above design in terms of throughput. Optimisation of freeboard accretion control was also a major component of the ramp-up activity. This paper discusses the commissioning and ramp-up issues of the new Ausmelt converting furnace, concentrating on the design and process changes, and summarises current operating performance against the original design objectives.

Jan 1, 2005

The Sishen iron-ore-mine produces 3 pro= ducts with size gradings of 25 to 8 mm, 11 to 5 mm and 5 to 0,2 mm and has a product capacity of 20 Mtpa. Ore is produced at an average Fe content of 66,2 % Fe for the two coarser pro= ducts and an average of 65,3 % Fe for the fine ore product. Three stage crushing is practised to re= duce the run-of-mine ore to -90 mm after which it is screened into five different size frac= tions of which four are heavy media beneficiated in static baths and cyclones and the fifth frac= tion discarded to slimes dams. A final three stage crushing and screening process is employed to produce the final three Products which are homogenized by means of blen=ding systems nrinr to despatch.

Jan 1, 1987

By A Annor, L J. Chen

The production of paste backfill has typically been accomplished through the adaptation of existing technology. Thickeners and disc filters have several drawbacks when applied to production of tailings paste backfill. Personnel at CANMETÆs backfill research laboratory in Sudbury, Ontario, Canada have been carrying out research into and development of methods to produce paste backfill using total mill tailings since 1991. Using a silo for production of paste is not a new concept but has been refined to a marketable level. This technology is based on a fluidization principle that assists in settling the tailings to an homogenous state in a silo. Other developments include patented de-watering technology for use in the silo to speed the settling of the solids to a suitable solids content, optimisation of silo geometry, and instrumentation related to paste backfill production and transportation. The advantages to fluidisation technology are in reduced capital cost, reduced operating costs and in the environmental benefits of using full plant tailings over classified tailings or alluvial aggregates. Another major advantage is in the ability of this technology to be retrofitted to existing hydraulic backfill plants to further reduce capital cost. This paper details the development of the new technology as well as the associated cost savings over other technologies. It will also look at the research and development of unique components that make this technology work.

Jan 1, 1998

By Duniam P

Sequencing of large underground firings is a critical aspect of blast performance. Using theory developed in open cut operations, where blast results are easier to quantify, a new technique for sequencing underground mass blasts has been developed. The basis for the technique is to identify timing regimes to control fragmentation and relief then apply non-electrics to fit these criteria. The use of computer software to graphically interpret delay statistics enables the evaluation of designs in a realistic manner.

Jan 1, 1995

By A van As

This paper serves to outline the circumstances and causes of the air-blast that occurred at Northparkes Mines in November 1999. It describes the design of the mine, the geotechnical issues surrounding cave propagation and the cave monitoring systems that were in place prior to the event. A short description of the air-blast that followed a sudden collapse is given. Details of the risk assessment process that evolved during the rectification process are provided with their subsequent modification to form the core of a major hazard monitoring process. The system is in line with the recommendations given by the Coroner resulting from the inquest into the deaths of the four people who lost their lives during the air-blast.

Jan 1, 2005

By L H. Chapman, I J. Kelso, N H. S Oliver

Utilisation of modern 3D visualisation tools, can improve our ability to correlate between different datasets, and thus to produce more accurate geological models. Here, we present an application of such techniques to the Century Zinc Deposit, northwestern Queensland, Australia. This stratiform orebody is the second largest Zn resource in the world (167.5 Mt at 8.2 per cent Zn, 1.2 per cent Pb, and 33 g/t Ag). It is hosted in the Page Creek Syncline affecting Mesoproterozoic shales and siltstones of the Wide Supersequence of the Isa Superbasin. As in other deposits, (eg McArthur River, Lady Loretta, George Fisher and Dugald River), the mineralised sequence is bound by an important regional structure, the Termite Range Fault, which partly intersects the deposit along its Eastern side. This fault is thought have been active during sedimentation and probably also during mineralisation of the lowest part of the Wide Supersequence. The anastomosing geometry of this fault system and crosscutting relationships with other NE trending structures indicate that it was reactivated several times from Mesoproterozoic to at least late Devonian times (>1000 million years in total); as a result, the ore sequence is subdivided into several fault blocks.Using two different computer modeling packages (GOCAD and 3ds max), we have reconstructed and restored the stratigraphic horizon with the highest Zn content, realised a series of isopach maps for each mine scale stratigraphic unit, plotted the three-dimensional distribution of Zn, Pb, Ag, Fe and SiO2, and have begun to evaluate the degree of correlation between thickness changes and sulphide zoning. With this approach it is possible to better understand the timing of mineralisation from a genetic perspective, because the origins of the orebody are controversial. Three-dimensional reconstruction is a vital tool for identification of syn-sedimentary and post-sedimentary fault activity. In conjunction with sulphide precipitation, these are factors that greatly influence the stratigraphic thickness distribution. Post-sedimentary deformation can be recognised directly by core logging and pit mapping, but the effect of tectonic movements during sedimentation (growth faults in particular), that represents a substantial variable when we attempt to reconstruct basin evolution, is difficult to evaluate without this methodology. The 3D models improve our understanding of the local basin architecture, identifying similar grade characteristics at different structural levels and thus suggesting that much faulting and folding are post-mineralisation events. In addition, we identified several growth faults adjacent to thickened layers, representing two possible sedimentary depocentres. These thicker domains apparently relate to the highest Pb content. If further analysis of rocks, thickness and grade distributions support this preliminary correlation, then a syn-sedimentary model for mineralisation might be applied, and would contrast with the sub-surface model for mineralisation of Broadbent et al (1998).

Jan 1, 2003

By Spencer GA, Saul SJ

The flight line spacing in low level aeromagnetic surveys is the principal factor governing both the cost and the amount of geological detail which can be extracted from the data. The rate at which geological resolution diminishes with wider line spacing is illustrated by progressive subsampling of a 200 m spaced data set from the Charters Towers region in Queensland.The usefulness of high frequency type filters in enhancing shallow structural features is seen to be limited to the 200 m data.It is concluded that each data set is suited to a particular scale and style of geological investigation with only the 200 m data having sufficient detail to identify the subtle structural patterns which are crucial to mineral exploration.

Jan 1, 1976

By Blackham M

West Wallsend No. 2 Colliery is a new mine that is presently being developed in the New- castle Coalfield by J. & A. Brown & Abermain Seaham Collieries Ltd., a subsidiary of Coal & Allied Industries Ltd. It is situated near Barnsley and is some 15 miles by rail from the port of Newcastle. The mine will produce coal from both Bore- hole and Young Wallsend seams. The Borehole seam has a working seam thickness varying from 7 ft to 5 ft while the Young Wallsend seam presents a choice of two distinct working thick- nesses, i.e. 5 ft. or 8 ft, the upper 3 ft containing much high ash material. The inter- seam interval varies from 10 ft on the western edge of the area to more than 70 ft in the central portion. The Borehole seam lies at a depth varying from 550 ft to 750 ft and the overlying surface terrain is gently undulating bushland with limited surface development.

Jan 1, 1972

The Jurassic Walloon Coal Measures crop out over much of the Moreton Basin and contain numerous thin, banded coal seams which have been mined at various locations since the 1870s. Historically most mining has been by underground methods. Increased exploration during the 1970s and 1980s has led to the delineation of significant open cut coal resources and to the development of the Oakleigh, Jeebropillly and Ebenezer open cut coal mines in the Rosewood-Walloon area. Over 2 170 million tonnes in-situ of shallow, high volatile bituminous coal with a mean maximum vitrinite reflectance of between 0.5 and 0.6 have been proven in the Basin.

Jan 1, 1991

FOR some years after the erection of the first chlorination plant at Mount Morgan the ore sent to the works for treatment was mined entirely from the oxidized zone; consequently, the bullion recovered at the refinery was of unusual purity, averaging about 972 in fineness, and, as no impurity in any way detrimental to the softness or toughness of the bullion was present, there was no necessity to subject it to any refining process.The charcoal from the filters was calcined to ash in small reverberatory furnaces of the usual type. The ash was mixed with suitable proportions of soda and borax to form a good liquid slag. This' mixture was then charged into salamander cruciblesand run to metal and slag in the ordinary wind furnaces-a slow and tedious proceeding in the Mount Morgan climate. The bullion, cleaned of slag, was re-melted under borax and poured into bars weighing from 350 to 400 oz.; these bars, after being dipped while hot into dilute sulphuric acid, were packed and sent to the mint. Of late years, however, the ore coming from the deeper ground of the oxidized zone became much lower in gold values, and contained variable but increasing quantities of sulphides, sulphates...

Jan 1, 1911

By Nemcik JA, Gale W. J

The magnitude and orientation of the in situ stressfield has been determined as a key factor in controlling the stability of openings for both coal mine development and extraction. Monitoring of roadway and pillar behaviour in conjunction with numerical analysis has identified specific stress control measures that have been successfully applied to improve productivity in underground coal mining operations. The influence of the major horizontal stressfield on the stability of openings has been identified at a wide range of sites including mines in Australia, Britain, the USA, New Zealand and Japan. Stress mapping, stress measurement and stress monitoring techniques have been applied to define the in situ stress regime and, together with the correlation of measurements of rock deformation and rock reinforcement behaviour, has enabled appropriate stress control measures to be developed. Stress control measures for development headings have required the selection of roadway orientation, roadway sequencing, reinforcement density and pillar size. The monitoring of behaviour at a range of trial sites has confirmed significant improvements in development stability. Stress control measures for longwall extraction have required rational selection of longwall orientation and extraction direction. Where a mine layout design incorporating the optimum longwall layout design has not been possible, the use of sacrificial roadways has been successfully applied to protect key roadways from stress concentration effects. Comprehensive in situ

Jan 1, 1992

The carbon-in-pulp (CIP) process is now well established in the South African gold industry, with a total of over I million metric tons of material being treated each month in six large plants. This tonnage is derived from ground ore, from filtered pulp, from calcine, and from reclaimed sand-tailings dumps. With this new process and the new large plants, those concerned with CIP are experiencing a learning process, since each new plant presents a different set of problems to be overcome. The knowledge and experience gained from these plants is being shared, and will be of benefit in the design and operation of new plants. The CIP process can be subdivided into the following unit operations: prescreening at a fine size, adsorption, acid-washing and elution, reactivation, and electrowinning. Results concerning each of these unit operations, which were obtained from pilot plants and from large-scale CIP plants in South Africa, are presented. The latest developments in each of these areas is summarized. Tables that are included as an appendix contain some information concerning the equipment in these new CIP plants plus operating results from some plants.

Jan 1, 1982

By G W. Croft, L E. Krause

The current copper ore handling systems in use at Xstrata CopperÆs Mount Isa Copper Operations are up to 33 years old and have hoisted over 160 Mt at a rate of around 6 Mtpa. The mineÆs production profile is increasing in line with the optimum life of mine plan to over 6.6 Mtpa, which requires a system utilisation and reliability above that previously achieved. Copper ore is hoisted up the U62 shaft, which forms the central part of the U62 ore handling system. In theory this system can cope with the duty planned if the bottleneck is only the U62 winder. To achieve the planned production rate will require increased focus on reliability of each component in the ore handling system so that ore is available at the shaft for hoisting whenever the shaft is available, and the shaft is available for the maximum practical time. Increased availability will be achieved through the outcomes of the study of each component in the U62 system, and the internal ore handling systems that deliver ore from as far as 2 km laterally and 700 m vertically from the U62 shaft. The true capacity of each component is being determined and current performance is being measured with the aim of improving performance through root cause analysis and engineering out the causes of delays. The program began in March 2004 and this paper describes the progress achieved as of April 2005.

Jan 1, 2005

By G MacDonald, B Forsyth, D Corkery, T

An investigation was carried out at Diavik Diamond Mines Inc (DDMI) to identify and quantify the mechanisms through which ammonium nitrate (AN) was entering the mine discharge water. The goal was to develop and complete an investigation of the potential AN loss mechanisms in order to assess their contribution to ammonia in the mine water system. The initial phase of the project involved the collection and analysis of blasting and water quality data that were used to determine the mechanisms by which the ammonia enters the mine water system and to establish a baseline data set for comparison with results from future trials designed to reduce AN loss. Three potential options for reducing AN loss were identified through the first phase of the project. The second phase of the project involved conducting a series of monitored trials with changes made to the drilling and blasting process. The results of these trials were compared to the baseline data set to determine if the changes introduced for the trials had reduced AN losses while producing satisfactory blast results. This paper describes the process for the collection of the baseline data, provides an analysis of the resulting data, discusses the changes made to blasting operations in order to minimise AN loss and describes the results observed subsequent to these changes.

Jan 1, 2007

By R Valenta

Most developing projects face a range of technical and non-technical challenges, and examination of development histories can potentially provide insights into improved approaches to project development. The Kestanelik project in the Canakkale region of Western Turkey was acquired by Chesser Resources Ltd in 2008. Turkey is a significant and growing source of gold production, with sector participation by both domestic and international companies. While the broad ranges of challenges faced by developing projects is well known, there are relatively few case studies in which the range of technical, environmental, social and governance challenges are presented in a single contribution. Recent studies of undeveloped complex orebodies have particularly shown the extent to which environment, social and governance (ESG) complexities contribute to project delays and failures. The Kestanelik project faced a full range of technical and ESG complexities, and provides an illustrative example of the associated challenges. CITATION: Valenta, R, 2018. A case study of technical, social and environmental challenges for a gold project development in Western Turkey, in Proceedings Complex Orebodies Conference 2018, pp 73–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

Portfolio management tends to separate the functions of Asset Allocation and Stock Selection, so the person responsible for reviewing an expert's report on a company would typically be choosing between companies rather than between a company and cash or bonds. How these choices are made depends on the investment time horizon, philosophy and style. Two styles, momentum investing and value investing are contrasted and the role of valuation methods within the framework of each style is evaluated. Finally, pricing is distinguished from valuation.

Jan 1, 1994

Traditionally, the term ætotal systemÆ design applied to comminution conjures images of a design that addresses the usual business and operational drivers, including health, safety and environment (HSE), capital cost, operating cost, throughput and product size. In terms of the physical process, the mine to customer type studies also exemplifies an approach that satisfies a normal ætotal systemsÆ approach. As an industry there are drivers that are forcing a re-consideration of what we regard as our total system. This modification of drivers will require changes in approach and implementation to provide the best solutions. Some of the major changes that impact the drivers are shortage of skilled personnel, changing social attitudes to remote mine site work, greenhouse gas emissions (GHGE), quality of available orebodies and geographical location of new mine sites. One approach to the challenges presented by the changing business environment is to expand the system envelope around comminution to ensure that comminution, in its widest sense, helps to meet the new realities. Background to the new drivers and constraints is provided and some of the appropriate responses are examined in relation to the impact on the total system.

Jan 1, 2007

By P Hogan, M Wells

Reflectance spectroscopy has become an established technique for mineral exploration and ore characterisation. However, there are few reported cases where the technique has been applied to the Hamersley Province channel iron deposits (CID). The Bonnie Creek CID, located ÿ140 km north of Newman in Western Australia, represents one of a number of CIDs recently discovered in the Hamersley Province. Reflectance spectroscopic analysis using the CSIRO HyLoggerÖ automated scanning system, in conjunction with X-ray diffraction and compositional analysis, was used to characterise and map the ore and gangue mineralogy in CID drill core. Using CSIROÆs spectral mineral characterisation scripts, it was possible to map the downhole distribution of the Fe-oxide abundance, hematite:goethite ratio and the gibbsite and kaolinite abundance. Spectral estimates of kaolinite abundance were found to be closely related to loss on ignition measurements at 650¦C and the spectral kaolinite abundance index provided a reliable estimate of the total weight percentage Al2O3 content. In addition, downhole HyLoggerÖ scanning of diamond drill core reliably mapped the distribution of kaolinite as supported by coincidentally elevated contents of alumina and silica. Furthermore, spectrally-derived estimates of iron oxide abundance were well related to assayed Fe wt per cent contents and use of the spectral iron oxide mineral index mapped the distribution of the goethite:hematite ratio, and demonstrated that material logged as high-grade ore in the Bonnie Creek CID was predominantly goethite-rich.CITATION:Wells, M and Hogan, P, 2013. Bonnie Creek channel iron deposits ore mineralogy - insights using the HyLoggerÖ technology, in Proceedings Iron Ore 2013 , pp 321-328 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013