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By D Matthews

With the increasing demand for quality-specific ores, coupled to the reality of even more complex minable iron ore reserves, there is a growing need for real-time online material analysis of plant feed and product. For a full system mass balance, the combination of conveyor weight scales, flow and density transmitters are required. This alone does not guarantee product grade. For optimal process control and material blending, real-time online elemental scans in combination with the mass weighting is becoming more than a ‘nice to have’. These elemental scans located at key positions, enable the mining and plant operators to make informed decisions timeously, therefore ensuring product outcomes and optimising operations where material grade and the control thereof are important. Typically, these units follow the mining and primary crushing circuit as well as on the product conveyors, low-grade conveyors and tailings lines. Deployed after the primary crushing circuit, an analyser acts twofold:1. guaranteeing mining production, and2. processing facility feed blends.The analysers on the product conveyors guarantee saleable product. The analysers on the low-grade conveyor and tailings line complete the elemental balance and identify the potential of the low-grade and tailings for future processing. The system losses (accumulation) are calculated to determine the amount of material ‘lost’ during the processing stage which does not report to any of the aforementioned and can be used as a measure of the efficiency of the plant. A further advantage of the real-time online analysis of material is that immediate intervention can be taken in the event that the product is not of saleable product grade requirements. In the Khumani Iron Ore mine, Northern Cape, South Africa, run-of-mine (ROM), product and control analysers were included. Run-of-mine and product stockpiles are certifi ed, low-grade material is not currently directly measured, but calculated from the internal control loops. Iron units are reconciled between product and feed material.

Jul 11, 2011

By H Park, V Sahajwalla

"Due to the increasing amount of gangues in iron ores, a beneficiation process is required more as a preliminary step for ironmaking process. However, mechanical grinding and washing of iron ore needs tremendous effort that increases operating cost. Therefore, there is a necessity of a novel approach to ironmaking which can tolerate considerable amounts of silica or alumina. In the present study, a high alumina-carbon composite pellet was examined for an ironmaking process. The effect of compositional changes in the CaO-FexOy-Al2O3-SiO2 oxide system on the reduction of carbon composite pellets was investigated in a purpose built thermo-gravimetric analyser (TGA) at 1473K (1200¦C). As a result, alumina increased the reaction rate of carbon composite pellets by increasing surface area, while silica decreased the reaction rate by lowering surface area of samples. Infrared gas analysis assisted with the reaction kinetics of carbon composite pellets through measurement of CO and CO2 in off-gases. This study will assist with establishing the new pelletising method which differs from the conventional fluxed pellets.CITATION:Park, H and Sahajwalla, V, 2013. Effect of CaO-FexOy-Al2O3-SiO2 oxide system on the reduction of carbon composite pellets, in Proceedings Iron Ore 2013, pp 467-472 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 12, 2013

INDEX OF CONTENTS.1. Historical.2. Manufacture.3. Heat Treatment.4. Fatigue, Failures.5. Consideration of the Establishment o£ a Central Testing or Proving Station.HISTORICAL.Since the introduction of improved high air pressure drilling machines in the early part of the century, efforts have been made to develop the quality of the rock drill bit, in order to take advantage of the greater increase of power output per unit weight of the machines (1). This resulted in the change from solid to hollow steel in the second decade of the present century (2).As the greatest sufferers from the dread disease of silicosis (3), it seemed appropriate that the South African gold mines should be the first to use hollow drill steel. Since then solid drills have become practically obsolete for mining purposes.Water is used with hollow steel drills not only to keep the cutting end cool, but also to assist in preventing the formation of undue dust during drilling. It is of interest to note, however, that water fed through hollow steel or sprayed into the air is only partially effective in removing fine dust particles a few microns in diameter, which particles are said to be the most potent in producing silicosis (3a).So far as the composition of "straight" carbon steel drills is concerned, a commission appointed by the Johannesburg mines carried out a very exhaustive series of tests on drill steels.These drills were manufactured from steel made by all the standard methods, including Swedish, Bessemer, crucible, openhearth, and, to a limited extent, electric furnace steel. It should be remembered that the commissioners' report was issued in 1913, when hollow drill steel had not yet been introduced. Only solid steel drills were then in use.

Jan 1, 1947

By F Faraj, M Pal, M Haest, M Bradshaw, H Lang, K Hume

MineSense Technologies Ltd. is revolutionising grade control at mining operations by installing ShovelSense® sensors on buckets that measure the grade of every load before it is dumped in the truck. This allows the mine to exploit grade variations at a resolution that was not available before, reducing the amount of ore loss to the waste stream and removing waste from material destined for processing. These changes dramatically improve the profitability and sustainability of mining operations. ShovelSense relies on X-ray fluorescence analysis of the rocks as they flow in the bucket and is integrated with fleet management to direct the trucks to the right destination. Lab simulations of ShovelSense measurements on porphyry copper ores show correlations between predictions and lab measurements at 0.98 r-squared with a coefficient of variation of 10 per cent. Visualisation of copper grade predictions in three dimensions shows a reasonable match with the dig plan, but with local changes in the ore-waste contact due to more accurate contact identification, related to blast movement and other mining factors. Correct delineation of these contacts ensures ore trucks are not sent to the waste dump and waste trucks are diverted from the crusher, creating enormous value for the operation and the environment.

Mar 22, 2022

By Mudge S. T

Tin mineralisation occurs at Renison Bell, near Zeehan in Tasmania, as a group of cassiterite-bearing massive pyrrhotite bodies in Cambrian sedimentary rocks. Mineralising fluids from the underlying Pine Hill Granite have replaced carbonate rocks with massive sulphides and cassiterite. The discrete blocks of massive pyrrhotite have high density and high magnetic susceptibility contrasts with the comparatively barren country rock. They are strongly remanently magnetised and are excellent geophysical targets. A detailed geophysical model of the mine was created from a database comprising 1:2500 scale geological mapping and geological logs of approximately 4000 drill-cores. The model comprises 93 parallel cross-sections, each 1.5 km long, spaced 20 m apart. Each cross-section is comprised of up to 150 polygons which represent all known individual rock types and orebodies. The magnetic response of the model was computed and the residual between the model and the observed response, measured by a low-level helicopter magnetic survey, revealed several anomalies unaccounted for by the model. Drill testing of these anomalies led to the discovery of several hitherto unknown massive sulphide occurrences. Surface gravity data of the mine and surrounding district were enhanced by applying digital terrain corrections. The corrected Bouguer anomaly revealed a hitherto unknown positive anomaly associated with the ore zones of the Renison mine. The gravity anomaly of the model was also computed. Unfortunately, the limited resolution of the observed data prevented the delineation of ore targets. The terrain-corrected Bouguer gravity data were also used to model the shape of the underlying non-magnetic Pine Hill Granite. A computer inversion method was implemented to build a 3D block model of the granite. Results agreed with previous conventional 3D modelling techniques but yielded improved resolution of the granite form. The project involved development of new computer software to build and edit the large and complex 3D geophysical model of the mine and to compute the model's magnetic and gravity responses. Software was also developed to build and compute the gravity response of a 3D block model of the underlying granite.

Jan 1, 1997

Through the stress synthesis of many exanples of macrostructure from eastern to western parts of China, it can be concluded that in Chinese tectonics there are two push- twisting forces, one of which ("Rl", from SE to NW) came from the Pacific Ocean plate thrusting over the Chinese continent plate in the eastern part of China; the other ("R2", from SW to NE) resulted from the thrusting of the India plate. The meeting line could be situated along the belt from 104¦-106¦E longitude in the middle part of China. To the south of Qinling the meeting line was an abyssal and giant fault situated from Longmen to the Er Inland Sea where the Tibet-Gansi fold system was intersqueezed to the Sidluan platform; to the north of Qinling, situated on the Fengxiang subsidence of the Eerduosi basin, the meeting line was located about 105¦E in Mongolia and appeared in the form of an arcuate structure, i.e. the Mongolia arcuate structure, which could extend to Beijiaer Lake towards the north. A new special type of structure named rotation-apart structure occurred from Gansu, Qinghai province to Ningxia, Neimeng autonomous region, in the west of Shandong province and in the western part of Chaidamu Basin.

Jan 1, 1987

By C M. Sennitt, M J. Spadafora

Systematic field evaluation of known gold and clay occurrences in South Korea has led to the recognition and discovery of both high and low sulphidation gold-silver epithermal systems. These are associated with Cretaceous acid-intermediate volcanic centres in the southern parts of the peninsula. The high sulphidation deposits such as Seongsan and Kohung are characterised by pervasive silica-alunite-dickite-pyrophyllite alteration with anomalous arsenic geochemical signatures. Gold mineralisation is associated with fine grained marcasite and pyrite. A low sulphidation quartz vein system observed at the Tongyoung mine comprises multistage colloform banded quartz-carbonate assemblages, with minor manganese and base metals. Gold and silver occur as electrum and tellurium minerals. Some deposits such as Gasado and Dogcheon display both high and low sulphidation alteration assemblages. Early pervasive silica-alunite-pyrophyllite alteration caps formed by acid fluids with a significant magmatic component, occur above cryptocrystalline colloform banded vein systems. The quartz vein stage hosts the precious metal mineralisation and appears to have been deposited by later neutral fluids generated in part through mixing with meteroric water.

Jan 1, 1999

By J Penman, N Turner, H Liu

This paper aims to present a snapshot of the risk profile for tailings storage facilities within Western Australia by comparing the spatial distribution of known facilities against common geohazards such as cyclonic activity, climate, and peak ground accelerations from earthquakes. The analysis also includes an assessment of proximity to populations at risk including towns and sensitive receptors including significant river systems and wetlands.

Jul 1, 2021

By Guo-Zheng J

This paper describes the risk management strategies adopted to control unstable slopes in the east open pit of the Daye iron ore mine. Extensive experience has been developed over the last 35 years in the management of pit wall instability resulting in the successful excavation and reinforcement of pit slopes over 350 m in height.

Jan 1, 1994

By P Wilson

The Mt. Wright Underground Mine is located near the town of Ravenswood in North Queensland and is operated by Carpentaria Gold – a wholly owned subsidiary of Resolute Mining Limited. The establishment of the world’s first Sub Level Shrinkage (SLS) mine from a tradition Sub Level Open Stoping operation has proven to be a geotechnical challenge which has required tailored solutions to overcome unique issues. This paper will be broken into two distinct sections that will outline: a brief overview of the mining method and how the SLS method was chosen; and how the SLS is managed and key geotechnical learnings. The story of the world’s first SLS originated from the need of a bulk mining method to ensure the viability of Mt. Wright into the future. Traditional bulk mining methods such as; Block or Sublevel Caving were originally ruled out due to the low natural ‘cavability’ of the orebody and the proximity of the orebody to existing major infrastructure (Decline, Ventilation Rises and Egresses). The first section of the paper will outline the key geotechnical information that helped decide the SLS method in addition to how continuous backfill influenced the design. The second section is intended to address issues that the geotechnical engineers encountered since the inception of the SLS. The feature topic of this section is mining induced stress. Like most bulk mining methods, Mt. Wright had success when the production front was running parallel to the stress (production front being ‘shadowed’ from the stress). This was until a design change, forced by a splitting ore body resulted in this shadowing effect becoming harder to achieve. As a result, rehabilitation and production hole re-drilling become a regular occurrence, which teamed with a strict set of access controls made the production cycle longer and harder to complete. CITATION:Wilson, P, 2018. Mt Wright – geotechnical learnings from a sub level shrink, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 119–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

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

Although giant strides have been made in the Australian mineral industry over the past quarter of a century in terms of mineral discoveries, self-sufficiency of commodities, contributions to exports and other aspects, there are unhealthy signs emerging which require attention. For instance there are 20 out of 34 discoveries of base metals, uranium and nickel which for a number of reasons await development. Some of the reasons for the standstill in the mineral industry are partly economic, partly due to competing land use, uncertainty in applying or, recognising the principle of crown ownership of minerals, and to some extent lack of appreciation of two closely related exploration activities referred to as development exploration and assessment Exploration.

Jan 1, 1979

By Kinsella B

Titrimetric studies have been carried out on the activated carbons Kintal 1105, Norit 2520 and Kuraray 2GA. Titration curves of the carbons before and after acid and water washing and gold loading indicate that the acid-base properties of the carbons are affected by both the method of treatment and also by the loading of gold. It is considered that the pKa values of the functional groups on the carbon surface are in the regions of 11, 7 and 3 respectively.

Jan 1, 1984

The green field discovery of a two million ounce high-grade refractory gold ore deposit in the Indonesian Province of Sulawesi Utara, led Newmont to utilise its proven technical expertise in dry grinding and whole ore roasting to develop a 2000 tonne per day, 160 000 ounce per year operation in this remote and picturesque location.Located at an elevation of 250 in above sea level and ten kilometres to a deep water natural harbour, the hard rock open pit mine, process plant and infrastructure facilities were built to budget at a capital cost of US$132 million. The plant was commissioned with oxide ore, with the first gold poured in March 1996 and with refractory ore in January 1997. The operation rapidly met its production targets because of extensive forward planning and training programs developed for the local workforce. The presence of steep topography, fertile coastal plains, high rainfall, high seismicity of this location led to the decision to dispose of neutralised tailings in deep water off the coast instead of impounding tailings in a dam. This paper describes the development of the project and the challenges in developing a gold operation in a remote location which lacked infrastructure, the steps taken to ensure a smooth commissioning, and the selection of the workforce to operate a technically sophisticated facility.

Jan 1, 1997

By G Hancock, J Lowry, W D. Erskine, D Jones, T Coulthard, M J. Saynor, P Lu

An 8 ha trial landform was constructed in late 2009 at the Ranger Uranium Mine, located 250 km east of Darwin in the wet-dry monsoonal tropics of northern Australia. The objective of the trial, which comprises two surface cover types on a uniform two per cent slope, is to provide long-term data to guide the development by Energy Resources of Australia Ltd (ERA) of its landform closure strategy. The scope of the work program for the landform includes many aspects; however, this paper is focusing on run-off and erosion rates. The run-off and erosion rates are used to assess the long-term geomorphic stability by comparing measured with modelled export rates from a landform evolution model.Monitoring of wet season run-off is undertaken collaboratively by the Environmental Research Institute of the Supervising Scientist (ERISS) and ERA, on four purpose-instrumented 30 m by 30 m erosion plots. Continuous measurements are made in rectangular broad crested (RBC) flumes located at the outflow of each plot, of water level, turbidity (a surrogate for fine suspended sediment) and electrical conductivity (EC) (a surrogate for solutes). Each plot has a tipping bucket pluviometer located near the RBC flume. Bed load is collected monthly.This paper reports the findings of rainfall and bed load from the first two wet seasons (2009 - 2010 and 2010 - 2011) following construction. The field measured loads will be compared with the predictions made by the Cellular Automaton Evolutionary Slope and River (CAESAR) landform evolution model. Initial results indicate that predicted rates of sediment export from the CAESAR model are similar to measured export rates. This provides confidence in the capability of the model to predict stability of the future rehabilitated mine area, especially during the critical initial years following construction. CITATION:Saynor, M J, Lowry, J, Erskine, W D, Coulthard, T, Hancock, G, Jones, D and Lu, P, 2012. Assessing erosion and run-off performance of a trial rehabilitated mining landform, in Proceedings Life-of-Mine 2012 , pp 123-132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By A Fern, A Hawkes, o

This presentation will cover: the importance of high-quality safety leadership; insights from a Safety Climate Survey that includes responses from 7903 employees working at 19 Australian mining organisations; the results of a critical control verification (CCV) coaching intervention; and recommendations for improving safety leadership in high-risk work settings. Safety climate is a representation of the deeper culture that exists in an organisation. Safety climate is predictive of behaviour, performance and reporting in organisations. Leaders play an important role in the establishment and maintenance of culture. Perceptions of safety climate were collected from 19 Australian mines (n = 7903 employees). These results indicate that the Australian mining sector is doing well in team support for safety and supervisor safety commitment. There were negative perceptions of willingness to report errors, employee involvement in safety initiatives, psychological safety and emergency readiness. Perceptions of safety leadership were in the fair range, with recognising behaviours perceived lowest, falling in the poor range. The underreporting rate was at 25 per cent indicating that 1 in 4 incidents are not being reported. Analyses exploring climate, leadership, safety behaviour and well-being will also be discussed. The integrity and success of critical risk management systems is often determined by the quality of safety leadership. Leaders need a mix of technical safety knowledge and interpersonal skills to be able to support the workforce to build critical control knowledge that invites open and collaborative discussions to find new or improved solutions. Forty leaders at a major mining operation completed training and 5-weeks of coaching focused on developing critical control verification competencies. The follow-up evaluation demonstrated significant improvements in relationship building, observation of controls and overall capability. Overall, insights from multi-organisation climate data and a prepost coaching intervention will be discussed and recommendations and practical guidance for leaders will be provided.

Apr 16, 2024

By G B. Smith

Barrick (Australia Pacific) Limited initiated a trial of Caterpillar’s Minegem autonomous loader technology in 2009 at the Kanowna Belle mine in Kalgoorlie. Autonomous loader technology offers the potential to improve loader productivity, reduce operating costs and improve safety through removing personnel from the mine operating environment. This paper discusses the implementation of the technology at the mine site, the data collected during the trial and quantifies the benefits of using automated loader technology in comparison with teleremote loader operation. The lessons learned from the trial and work planned for the future in respect of this technology is also discussed.

Mar 21, 2011

By Laros T, Schoenbrunn F

Deep paste thickeners have been proven capable of consistently producing medium to low slump material for disposal without the need for filters. However, proper design of the entire system is critical for a paste project to he successful. Some of the factors that must be carefully considered in design of a paste system include thickener sizing, tailings inipoundineni design, underflow pumping, and control system.

Jan 1, 1998

A nine-month investigation was conducted into the effect on coke quality and blast furnace operation of the addition of bentonite and southern coal to the northern coal fed to the coke ovens at the Newcastle steelworks.Additions of 0·3 per cent bentonite or 25 per cent southern coal to the northern coal increased the coke strength from 15-20 A.S.T.M. stability to 25-30 A.S.T.M. stability. It is likely that improved mixing and blending facilities would, in both cases, give a coke of over 30 A.S.T.M. stability.For the same coke strength, the use of 0 3 per cent imported Wyoming bentonite was considerably cheaper than the use of 25 per cent southern coal, but the use of Australian bentonite promises the same coke strength for still lower costs. Other additives such as coke breeze, charcoal, iron ore fines, and certain other finely divided materials, gave relatively minor improvements in coke quality.There appeared to be sufficient improvement in blast furnace operation and production to justify full scale addition of bentonite to improve coke quality, although other variables, particularly iron ore physical quality, overshadowed on many occasions the effect of coke quality. Further coke trials with southern or bentonite will be carried out when ore quality has been improved by the introduction of ore sintering at Newcastle.INTRODUCTIONDuring the period of operation of the Newcastle coke ovens and blast furnaces from April 1960 (when No. 3 blast furnace was blown in after rebuilding) to December 1960, a bentonite coke trial was carried out based on earlier research findings (Gregory, 1959a, 1959b; Felton and Gregory, 1960; Gregory, 1960) that as little as 0 3 per cent to 05 per cent bentonite clay added to northern N.S.W. high volatile coking coals gave a significant increase in coke strength. The bentonite coke trial was followed by trials...

Jan 1, 1962

By M J. Nugus, F Clark, E J. Hill, J T. Carswell, J S. Cleverley, N H. S Oliver

High-nugget gold orebodies are difficult to model in 3D because samples from diamond drill core are generally too small to provide reliable estimates of the gold content of the larger body of rock, and therefore interpolation of gold assay values between drill holes is also unreliable. As a result, gold resources are generally underestimated in areas of high nugget. In practice, proxies for gold mineralisation, such as presence of alteration, specific structures or high vein density, have been used by geologists to predict rocks which are favourable for mineralisation. However, there has been no automated method for combining the predictive capabilities of several proxies, except by human judgement.We have been developing a method to combine several different types of geological features or geochemical analyses into a single measure using conditional probability. Conditional probability provides a meaningful numerical measure for the favourability of rocks for containing high-grade gold mineralisation. This measure can be interpolated in the exploration space, providing a sound basis for a 3D model of the orebody. We have developed this technique using data from the Sunrise Dam Gold Mine, which is a high-nugget orebody hosted in a structurally complex Archaean greenstone belt and which has historically proved to be a very challenging orebody to model.CITATION:Hill, E J, Nugus, M J, Clark, F, Oliver, N H S, Cleverley, J S and Carswell, J T, 2013. Predictive three-dimensional modelling of nuggety gold orebodies, Sunrise Dam, Western Australia, in Proceedings World Gold 2013 , pp 463-468 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013