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By R Jaine, D Strang, M Fowler

"This paper presents a case study demonstrating active geotechnical pit slope management at the now completed Carina Iron Ore Project operated by Mineral Resources Ltd (MRL). The site is located 105 km north-east of Southern Cross, Western Australia. The paper is primarily focused on the slope stability failure modes and the remedial measures employed to maintain mining.Between a quarter and a third of the excavated slopes were impacted by some form of instability that was beyond expectations of the intended slope design criteria and common practice. Ongoing mining was supported by intensive geotechnical pit slope management including close cooperation between geotechnical, mine planning and operations staff to achieve timely and practical mining solutions.Mining encountered varied slope failure mechanisms which required a combination of remedial solutions comprising: horizontal depressurisation holes, deferral of excavation, unloading, buttressing and catch berms.The root cause of the challenging slope performance was a mismatch between the predicted and encountered geotechnical model, resulting from a failure to recognise the critical mechanisms that control slope stability.Despite the extensive zones of instabilities at completion of mining, full ore recovery was achieved without major delays and in a controlled and safe manner.Citation:Fowler, M, Strang, D and Jaine, R, 2016. Adapting to Geotechnical Change - a Case Study of the Carina Open Pit Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 150–161 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By R C. Owen, M A. Ward

The paper describes the application of New Zealand's environmental impact assessment procedures to a proposed gold and silver mine in the North Island of New Zealand. The project is described and a summary is provided of the statutory permits or consents that are required prior to operation of the project. Emphasis is given to the requirement for environmental impact assessment and the preparation of a formal environmental impact report. The company's approach to impact assessment is described, with examples of how this assessment and the identification of management alternatives influenced the engineering design of the project. This paper was prepared as a contribution to a working session of the International Association of Impact Assessment VII Annual Conference, July 1988.

Jan 1, 1988

Nuclear power stations to be installed in Australia will be fuelled from Australian resources of raw materials.This will require the establishment of new manufacturing industries and the eventual expansion of established activities, especially in uranium mining and the preparation of precision metal products.This paper presents some predictions of the possible growth of nuclear power installations in Australia.These might amount to 4000 MWE by 1985 and 11,500 MWE by 1990 and towards the end of the century, about 50 per cent of new generating plant might be nuclear.Predictions are given of the demands for materials (uranium and zirconium) and fuel manufacturing services for four reactor systems which might be considered in the programme.The availability of raw materials and technical capability place Australia in a particularly good position to undertake the manufacture of nuclear fuel; in addition to satisfying the domestic demand we should actively seek export markets for these products.

Jan 1, 1971

In the time since the first trials in the mid-1980s, the Rare-Earth Magnetic Separators (REMS) are presently (year 2001) found in many heavy mineral sands plants around the world. Both the roll and the drum type are used from ilmenite concentration to cleaning high-purity zircon products. Chromium-bearing materials are removed from ilmenite more selectively than with electromagnetic separators. Greater flexibility and higher grades in ilmenite circuits are achieved. Cleaner rutile and zircon products, even with respect to levels of radioactive materials, are the result of superior magnetic force optimisation. Tailings from roaster plants can be reprocessed effectively, which is encouraging some operators to look at replacing old equipment in order to process roasted material plant feed or implement use of the new generation drum separators in new plants. Wet separation of ilmenite by using powerful wet REMS drum separators is now a possibility. This may be an alternative to at least a portion of the Wet High-Intensity Magnetic Separators (WHIMS) process for ilmenite preconcentration. A dry plant process flowsheet can often be modified by displacing a portion of high-tension separators with new high-temperature tolerant REMS.

Jan 1, 2001

Coal exploration and mine planning now use all the modem techniques to indicate geological hazards to a new or developing coal mine. Drilling, seismic and other sophisticated geophysical methods aim to increase the reliability of prediction of features which will inhibit mine development. But do they?. During the past 40 years, geological investigations for coal mines in New South Wales have ranged from the general observations of Eric Rudd, in the Southern Coalfield in the late 1940s to the very detailed examinations of roof strata by John Shepherd and others in the 1980s. Then, the large scale regional relationships between sedimentary and structural features often were ignored as the minute examination of seam roof strata became fashionable.

Jan 1, 1991

By Luck D

Current methods of mucking out small development tunnels are a major limitation to improved efficiency and high rates of advance. This is particularly true in the deep metalliferous mines of South Africa, where the harsh environment, remoteness of operations and the hard abrasive rock conditions mitigate against the use of the tunnel borer type of equipment. The Loader Distributor Train was designed to overcome the special problems of hard rock tunnelling. It combines advanced innovative technology with proven simple methods of operation and maintenance. The system aims at taking advantage of new, efficient and cost effective power sources in South African mines based on replacing compressed air with electro hydraulics and the new concept of hydropower. It also introduces electronics and computer technology, for both automatic control and fault finding, into the production environment. The system is designed to permit sophisticated equipment to be operated and maintained by a semi skilled labour force. Although still undergoing trials it is believed that the Loader Distributor Train will prove highly effective, and that the new concepts offer considerable potential in areas other than flat tunnels, in particular the cleaning of inclined shafts.

Jan 1, 1986

By J Wiklund

The impact of non-ferrous smelters on their local surroundings is well monitored and guarded by various actors: the owners looking for profitability, the villagers looking for employment, the consumers asking for ever cheaper products and services, the government collecting taxes and all cherishing the environmental impact. Recent challenges facing the industry are various new doomsday projections: that we will be running out of base metals, that the ground we dwell on will be contaminated by the use of products. Smelters, such as BolidenÆs R÷nnskSr Smelter have a long history of increasing non-ferrous resources by recycling. It is shown that extraction and recycling of metals together with energy recovery can be integrated in a modern, profitable and clean smelter. Examples of efforts to further improve the business will be discussed such as flowsheet rationalisation, environmental investments, new feed from recycling and energy utilisation.

Jan 1, 2000

By T Hodgkin

The WA Goldfields is a highly productive gold and nickel mining area, but is arid with highly saline groundwater. Groundwater is widely used to supply process water to mines in the region but high groundwater salinity, commonly exceeding 50 000 mg/L TDS, tends to increase processing costs, limit end uses for the water, cause problems with disposal and potentially increase impacts on a sensitive arid environment. The area has low rainfall (200 - 270 mm/year) but run-off, particularly during cyclonic events, is high. Our experience suggests that stream flow from catchments in the area can produce a divertible yield of 8 - 17 ML/km2/year. An evaluation of stream flow harvesting using AnglogoldÆs Jubilee Pit predicted that 1000 ML/year of good quality water could reliably be supplied to the Sunrise Dam Gold Mine. Because of high rainfall variability, it is likely that an alternate source of water supply will be necessary when operating a surface-water harvesting scheme in the WA Goldfields. However, a combination surface/groundwater supply could have substantial cost, operational and environmental benefits compared to traditional supply systems that utilise groundwater only.

Jan 1, 2003

By S MacKinnon, J Kok

Potential areas for improvement in flotation performance were identified during JKTech model development surveys in October 2003. Subsequent implementation of the JKTech recommendations in consultation with flotation cell manufacturer Outokumpu have resulted in gold flotation recovery increases of more than four per cent over a two-year period. One of these recommendations was the installation of High Shear Stators in the Cleaner and Recleaner flotation cells. The High Shear Stator installation project was justified based on simulations completed using JKSimFloat. Bubble size measurements completed before and after installation of High Shear Stators showed a reduction in mean bubble size of approximately 50 per cent in the Cleaner cells. Both Cleaner and Recleaner banks showed a significant narrowing of the bubble size distributions following the installation. Plant gold recovery increase resulting from the installation of High Shear Stators was 1.1 per cent, with a 1.9 per cent increase in flotation gold recovery and 5.4 per cent increase in flotation sulfur recovery. Based on the 1.1 per cent recovery increase and total project cost of less than $200 000, the High Shear Stator Project NPV was $8 200 000 with a 0.25 year payback period.

Jan 1, 2006

By K Nakashima, K Aya, T Sumita, N Saito

Electro slag remelting (ESR) is one of the methods used to produce high-cleanliness steel. In the ESR method, the product steel electrode is immersed in flux, and the electrode is melted by the Joule heat of the flux generated by high current. CaF2-based melts are mainly used as fluxes, but the electrical conductivity of CaF2-based melts varies widely among researchers and measurement methods. Therefore, this experiment aims to measure the electrical conductivity of CaF2-based melts based on the van der Pauw-Ohta method, which does not require the cell constant that is a fundamental error factor in electrical conductivity measurement at high temperatures. The measurement temperature was set at 1450–1600°C, and dehydrated Ar flowed through the furnace at 200 mL/min. Electrodes were fabricated by Pt-30mass per cent Rh alloy, and the electrodes were connected to an impedance analyser using a four-terminal probe. The electrodes were immersed in the melt, and the impedance and phase angle were measured by AC frequency sweep (50 Hz to 200 kHz). The electrical conductivity was then calculated by utilising the impedance’s real part values when the impedance’s imaginary component was zero. The electrical conductivity showed a positive temperature dependence. The electrical conductivity of 60(CaO⋅Al2O3)-40CaF2 melt increased with increasing temperature but was found to be roughly one-third of those of the previous studies. In the conductivity measurement of 60(CaO⋅Al2O3)-40CaF2 melt, the AC frequency with a phase angle of 0° was found to be different depending on the temperature and immersion depth. By sweeping the frequency, the impedance at the phase angle of 0° can be obtained, which enables us to measure the electrical conductivity more accurately.

Jun 19, 2024

By I Chan

The Wambo Rail Spur located near Singleton, New South Wales, Australia, runs for 14 km linking the Mt Thorley rail loop and running north-west alongside Jerrys Plain Road to the Wambo Coal Mine at Warkworth. A portion of the project is a 260 m long tunnel located where the rail line passes under Jerrys Plain Road. The tunnel has a low cover and is mostly within highly weathered to fresh laminated siltstone interbedded with coal seams, sandstone and conglomerate. This paper presents the design basis and construction methods used to achieve the 100 year design life of the tunnel required by Wambo Coal while also satisfying settlement and vibration limits imposed on Jerrys Plain Road. 

Jan 1, 2008

The equipment and general smelter layout for the Mount Isa Copper Smelter were designed by engineers associated with the American Smelting and Refining Company and by Mount Isa staff engineers. The final notice of site was dictated by the need for 'building the smelter near the existing Mount Isa power house to enable full use to be made of the steam from the waste heat boilers. Although much excavation work was necessary before concrete foundations could be poured, the location lends itself to further expansion should it become necessary. The plant is designed and constructed to involve straight line smelting operations which include the following major steps in the overall scheme.1. Charge make-up.2. Roasthig.3. Reverberatory smelting.4. Converting.5. Refining.6. Casting.CHARGE MAKE-UPA system of proportioning bins is provided for preparing the feed mixture for the roasters, Sulphide concentrate containing 24% copper wiil be delivered by belt conveyor from the filter plant to the smelter storage patio. This is a large roofed concrete floor that provides a maximum storage capacity of 8,000 tons of concentrate. Eight proportioning bins located below but adjacent to the south end of the patio will be used for actual charge make-up from which concentrate, ore and flux will be proportioned to the feed belt and conveyed to the roaster feed hoppers. Four of the proportioning bins, 80 tons capacity each, will receive...

Jan 1, 1953

By B Hall

In feasibility studies the choice of optimum cut-off grade is typically based on an evaluation of tonnage grade curves and manual design of stopes at one or two cut-off grades. In the industry these stope designs are usually based on break-even cut-off grades, but there is little consensus on what cost and price assumptions ought to be included. A new tool for automated stope design has been developed that generates sets of stope shapes for a nominated range of cut-off grades, or depending on the nature of the mineralisation, cut-off values based on net smelter return calculations in the block model. The stope design procedure includes constraints in stope and pillar geometry for the selected mining method and can be used to evaluate sublevel interval and sensitivities to other design parameters in the specific geological and geotechnical environment. These ænested stopesÆ are analogous to ænested pitsÆ in open cut design, and can be used as a key input in the æhill of valueÆ methodology for the evaluation of the optimum cut-off grade in underground design. The results of many consulting studies indicate that a break-even cut-off grade will not be the optimum cut-off grade. A particular benefit of the new stope design tool is that the design rules used to establish stope shapes in the feasibility study can then be used in mine production, in an optimal and repeatable method. This methodology is being advanced in the AMIRA P884 PRIMO project, which is a new research collaboration coordinated by AMIRA International. The project has brought together active research groups in Australia and Canada, with the goal of developing a flexible framework and set of software tools for optimisation in underground mine design.

Jan 1, 2009

By D A. Collins

The floatability methodology developed by the AMIRA P9 project through research contributions by the Julius Kruttschnitt Minerals Research Centre (JKMRC, Brisbane, Australia), University of Cape Town (UCT, Cape Town, South Africa) and McGill University (Montreal, Canada) has been successfully commercialised through JKTech. The methodology involves detailed flotation plant campaigns which require large quantities of data to fit models that can be used in JKSimFloat (a steady state simulator for the flotation process). The methodology to date, although widely accepted as the best flotation optimisation technology available, is limited to existing circuit optimisation and requires full plant or pilot plant data to calibrate new models. The floatability of new ore types cannot be characterised using this method unless a pilot campaign is undertaken. After reviewing a large database of existing industrial floatability data, a new methodology is proposed that involves a laboratory based flotation test procedure and review of the floatability database to characterise the floatability of new ores. The full methodology is labelled the floatability index test procedure (JKFIT). This paper outlines the JKFIT procedure and the results of applying this methodology to pilot plant data from a copper ore. JKFIT was applied to two different feed sizes (namely a P80 of 180 microns and 212 microns) of this copper ore. The results of applying JKFIT to this case showed that the metallurgical response (in terms of grade and recovery) from the full pilot plant survey data could be predicted well. Further validation of this methodology was conducted on a separate copper ore. The results from this validation also showed that the JKFIT test was able to be used to predict the full plant performance. The JKFIT test has the potential to become the 'drop weight' test of flotation which will improve the confidence in plant design flow sheet layouts, allow full orebody characterisation and prediction of key grades and recoveries before the ore enters the plant, and will provide an improved methodology for chemistry impact analysis on different ores.

Jan 1, 2008

By Lin Bin, Minggao Qian, Zhiyi Yang, Fullan He

There are no efficient methods and instruments available in China at present for diagnosing the leakage problem for a hydraulic support system in underground coal mines. A new method has been developed to solve the problem. It is proposed that

Jan 1, 1998

The MIMDAS geophysical data acquisition system developed and tested by the former MIM Exploration Pty Ltd (MIMEX) is now commercially available worldwide through Geophysical Resources and Services Pty Ltd (GRS). The system implements several new features in its design that give it significant advantages over conventional systems and allows for new approaches to electrical exploration. In particular, the achievable signal to noise levels permit exploration to depths once thought beyond the range of electrical exploration. The flexible multi-channel configuration lends itself to truly 3D surveys in the style of modern seismic techniques. Each of these aspects is illustrated with a number of case histories from both Australia and South America.

Jan 1, 2004

By E Broers, J Goh, S Davies

With recovery being important in optimising the business performance of a laterite and sulfide plant and with water being a precious resource in Australia, there has been increased pressure for companies to improve their methods of improving liquor recovery and improving water recovery in both laterite and sulfide plants. This has resulted in new control technologies such as the Manta Cube being applied on countercurrent decantation (CCD) and thickening circuits which is necessary to improve stability and optimise the liquor and water recovery in these processing plants. This paper describes the benefit of applying these new control techniques on CCD and thickening circuits in some of the mineral processing plants in Australia.

Jan 1, 2009

By M P. Schwarz

A major issue presently faced by companies producing and processing iron ore is the need to maximise throughput while minimising capital expenditure. While present high demand means this is of prime importance, the perennial issues of maintenance, operating costs, reliability, quality and environmental sustainability are also critical to profi tability. Attempts to address these issues generally require modifi cations to existing equipment, or trials of new equipment when designing plant for new projects.The risk involved can be substantially minimised by testing equipment improvements using advanced computational models prior to implementation. Examples of application of Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) modelling to sampling, cyclones, conveyor transfers, classifiers, dust control, banana screens, comminution and smelt-reduction will be given to illustrate the benefi ts of such an approach. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

By I H. Jung, W O. Choe

Gallium (Ga)-containing compounds such as Gallium Arsenide (GaAs) and Gallium Nitride (GaN) are widely used in electronic devices due to their superior electro-optical properties and their usages increase rapidly. For the sustainable supply of Ga to electronic industry, therefore, the recycling of Gallium becomes essential. Pyrometallurgical Ga recycling process involves the complex chemical reactions between slag, matte, liquid metal, gas, refractories, etc. Therefore, the accurate thermodynamic information and phase diagram data for the oxide system containing Ga2O3 is important. In the present study, new phase diagram experiments for binary SiO2-Ga2O3 and ternary CaO-SiO2-Ga2O3 system are carried out using Differential Thermal Analysis (DTA) and quenching experiments followed by Electron Probe Micro-Analyser (EPMA) and X-Ray Diffraction (XRD) phase analysis. Based on new phase diagram data and available literature data, the thermodynamic modelling of the entire CaO-SiO2-Ga2O3 system is performed for the first time.

Jun 19, 2024

By Peck WH

For many years it was realised that the methods used for unloading concentrates at Port Pirie were inefficient and labour intensive, therefore, when a decision was reached to standardise the east-west rail link from Sydney to Perth, the opportunity was taken to consider entirely new schemes for the handling of concentrates at Broken Hill and Port Pirie. After considerable testing and investigation, it was decided to install a completely new concentrates handling plant incorporating a tippler at Port Pirieòto replace the previous long established methods of unloading and dis- tributing concentrates to the operating plant.and the shipping berths. To achieve this, wagons of concentrates from the various mines are marshalled in a set order at Broken Hill and conveyed to Port Pirie in 56-wagon trains. On arrival at Port Pirie, the wagons are checked and moved to a position where they come under the control of the automatic wagon marshalling equipment.

Jan 1, 1975