Search Documents

By M W. N Buxton, M T. Bootsma, J Benndorf, C Alford

Research in the field of cut-off grade optimisation has shown a relationship between cut-off grade, project life and net present value (NPV). Lane’s theory demonstrates that cut-off grades can be optimised in order to maximise project profitability. Although the theory forms the basis for many open pit mining projects, application of the theory in underground mining remains limited to-date. The main reason for this is the complex interaction between all processes in underground mine planning, which makes it difficult to apply Lane’s mathematical optimisation approach.Recently a new stope optimiser product was released. The AMS Stope Optimiser automates the design of underground stopes at user-defined cut-off grades and allows for rapid evaluation of mine designs at different cut-off grades. Using this software, an optimisation approach was developed and validated on an underground gold deposit in northern Sweden. Potential project NPV increased by approximately 30 per cent when using this new approach.Spatial grade uncertainty in mineral resources was identified to be a major risk in underground stope design. The optimisation approach was further extended to account for grade risk using estimated and stochastic simulated resource models. The resulting optimisation process accounts for grade risk early in the design process and reduces the risk of a stope not meeting the cut-off grade with subsequent financial loss.CITATION:Bootsma, M T, Alford, C, Benndorf, J and Buxton, M W N, 2014. Cut-off grade-based sublevel stope mine optimisation – introduction and evaluation of an optimisation approach and method for grade risk quantification, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 281–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By G R. Power

A useful way to assess potential productivity of SLC mines is by quantifying tonnes/drawpoint/day to be extracted from the mine. However limited industry information has been published to help mines benchmark this number. This paper assesses industry data which can be used to support estimates of potential productivity from new mines based on tonnes/drawpoint/day. The information used has been extracted from historical production schedules which indicate what was achieved, rather than what was planned. It has been assessed using an algorithm created for the purpose and is presented with discussion of varying definitions of active drawpoints, analysis of the data and inquiry into some of the underlying contributing factors.

Mar 15, 2021

A 1991 survey of 48 mining companies, employing more than 24 000 employees, showed that disabling injury and disease rates continue to be the most common measurements of safety management effectivness in the Australian mining industry.Of the companies surveyed, 22 claimed to be making regular safety audits. Of these only two listed the improvement of audit scores among their goals for 1991.Influenced by loss control management thinking, some managers have expanded the scope of their safety programs to include all accidental operational losses adversely affecting mine profitability.Learning from their new experience with total quality management some managers are now recognising that successful safety management outcomes depend on the effective management of program inputs. They are thus turning away from measurements of accident consequences - the failures of the management system - to measurements of management control.The new focus of safety management attention is now on corrective actions before accidents happen.

Jan 1, 1992

Intrusion related Cu/Au mineralisation is localised in Pacific Rim island arcs by arc parallel, termed accretionary structures; or arc normal, termed transfer structures. In Papua New Guinea, NE trending transfer structures, evident on Landsat imagery, represent deep crustal fractures which have facilitated dextral rotation of the mainland during oblique plate collision. Major structures localise intrusion centres, and by rotation, develop ore hosting dilational environ-ments in subsidiary structures. While transfer structures localise the Porgera, Wafi and Yandera porphyry centres, the Frieda Porphyry and associated Nena high sulphidation Cu/Au mineralisation are localised by accretionary structures. The Bulolo Graben, which hosts the Morobe Goldfield, developed during intra arc rifting aided by movement on transfer structures. Crustal thinning has initiated magmatism with which diatreme breccias and fracture controlled mineralisation are associated.

Jan 1, 1994

By Whitworth N, Anderson P

New plant has been commissioned to treat off-gases from the Fluo-solids Reactor in the Copper Smelter. The new section of plant was built onto an operating system and commissioned with minimum disruption to production. Under construction is a 270 m tall stack for Lead Smelter gases. Additional items for the Lead Smelter will include a new gas cooler, a central baghouse to replace Sinter Plant wet gas scrubbers, a new exhaust fan on the main baghouse, and ducting of drossing gases to the main baghouse. Emphasis is given to discussing improvements the new plant has made to working conditions, the general environment and increased production capability. Total expenditure in the two smelters is in the order of $25 million.

Jan 1, 1978

By M Lovitt, T Hewitt

The extraction of drawbells in Lift #2 at Northparkes Mines E26 orebody was achieved by single shot blasting, enabled through the use of electronic detonators. This paper discusses the designs considered at the time of the feasibility study and the various changes made to these designs prior to and during the construction phase of the Lift #2 block cave. Operational issues encountered are highlighted, as are ways in which these were overcome. The amount of personnel utilised to mine the drawbells is also covered. Lists of design and operational considerations to be used for drawbell extractions have been included.

Jan 1, 2005

Mineral deposits in New Zealand whose origin can be ascribed to primary magmatic segregations are associated with mafic-ultra- mafic complexes related to two orogenic episodes which took place during Paleozoic and Mesozoic times. These mafic-ultramafic complexes are essentially of two types. One is ophiolitic and has podiform chromite mineralisation presumably formed below a spreading ridge. The other type occurs as intraplate layered intrusions in which Fe-Cu-Ni sulphides and Fe- Ti-V oxides have formed as a result of liquid immiscibility with the host magma, and have subsequently accumulated by gravity means. Generalised descriptions are given for some deposits in NW Nelson, Fiordland and Marlborough districts.

Jan 1, 1980

By A-M Fleury

There has been much progress on the issue of acid drainage over the past 20 years; however, significant challenges remain. The International Network for Acid Prevention (INAP) is attempting to address them by globally coordinating acid drainage information sharing and research. INAP pursues three branches of activities: it links AD research, practice, and people; it organises, sponsors, and participates in regional workshops as a forum for technology transfer; and it instigates and funds key acid drainage research projects. Through these activities INAP is helping the industry deal with what is arguably its most serious legacy issue.

Jan 1, 2003

By S Strong, L I. Sanz Vivanco, T Brown

One of the most significant technical and practical challenges facing the tunnel construction team on the Legacy Way road tunnel project in Brisbane, Australia was how to erect the prestressed precast concrete slabs to form the smoke duct in the tunnel boring machine (TBM) tunnels.An essential part of the tunnel ventilation system, the smoke duct extends the full length of the 4.6 km-long twin two-lane tunnels. The vast majority of the tunnels (approximately 4.3 km) were constructed using two 12.4 m diameter double-shield TBMs. The refurbished Herrenknecht machines broke several world records on the way to completing the tunnel excavation works in just over nine months. With the excavation complete the focus turned to solving the complex civil tunnel fit-out challenges. A key component of the civil fit-out of the tunnels was constructing the smoke duct in the TBM tunnels, which was designed as a precast solution.The slabs, which each measure 8.62 m long × 2.0 m wide × 200 mm thick and weigh close to 9?t, need to be erected above cast in situ corbels whilst other tunnel finishing works continue. The space-proofing clearance offered by the design to the support corbels below and the precast segmental lining above was in the order of only 100 mm.This paper tells the story of how the Transcity Joint Venture (JV) tunnel fit-out team comprising some of Europe and Australia’s leading tunnel construction specialists drew upon the global strengths of the existing JV member companies and the global reach of leading TBM manufacturer Herrenknecht to develop an innovative system in solving this challenging problem. This globetrotting story, which starts in Australia, visits Europe and mainland China before returning to Brisbane where it all began.CITATION:Brown, T, Strong, S and Sanz Vivanco, L I, 2014. How the global experience and reach of tunnelling’s true multinationals helped solve a road tunnel fit-out challenge, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 507–512 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By M Edhammer

In 2007, Atlas Copco introduced an integrated tunnel scanner/profiler. The tunnel scanner, which is integrated into the control system, is mounted on the drill rigs, and replaces the previous variants of non-integrated scanner equipment. The Atlas Copco Tunnel Profiler, which is the name of this system, is currently being used by several contractors and mines on various projects in Scandinavia, Finland and Australia. Atlas Copco Tunnel Profiler can scan a tunnel of 65 m2 in just five minutes and is integrated with the computerised control system for the drill rig. This integration means that the results of scanning are immediately available for analysis on the computer screen both in the drill rig and in Tunnel Manager; a software for tunnel and drift planning.In 2008, a method was introduced for locating the drill rig with a total station navigation (TSN) system, integrated into the control system. TSN systems are used by a number of contractors in Scandinavia and Finland, as well as elsewhere in the world. Using a TSN for navigation is in itself not new, but when this is integrated with the control system it provides the opportunity for individual drill rig operators to use this method, without the direct assistance of a surveyor. TSN gives a very precise indication of the drill rig’s position in relation to the tunnel design. An accuracy of ±1 cm compared with the ±10 cm which is normally obtained with the traditional method using tunnel laser and sight plates on the drill rig’s feeder. The closer a tunnel is blasted to its planned profile, potentially the more is saved in terms of less shotcreting, extra rock bolting and other corrective work. A better quality tunnel is the key to better overall economy and today’s technology makes it possible to achieve that goal in every type of tunnelling and mining project.In addition to total station’s ­navigation and Tunnel Profiler, the concept of ‘high precision tunnelling’ also includes:•Software tunnel planning: Tunnel Manager, Tunnel Manager Pro and Tunnel Manager Measure while drilling.•Measurement While Drilling (MWD)collects the various drilling data and the interpretation of these for the early identification of variations in the rock.•Rig Remote Access (RRA) is a support for wireless or wired communication between drill rig and planning office. The result is being able to send planning data to the drill rig and to simultaneously have the facility for logged files to be sent from the rig to the office. There is an option of an external computer logging in to the drill rig’s control system to view menu screens and settings, and remotely troubleshoot and plan appropriate action.

Mar 21, 2011

By G Fahey, S Rose

"Mining geology as a defined profession is only about 100 years old. The successful modern mine geologist needs to be a multidisciplinarian, but also needs to maintain a focus on the key outputs of the role. The technical skills needed in the role have increased as mining methods move to increasingly mechanised techniques. As well as being the guardian of the orebody and ensuring minimal dilution to expected ore grades, the mine geologist should be competent in the 12-point mine geology process. The mine geology process should include:a statement of purpose (a ‘mission statement’)geological mapping/logging system that supports consistent and regular geological data collection, storage, and interpretationsampling system that can produce representative samples and fits in with the mining scheduleassay database with relevant controls to ensure only ‘clean’ data is loadedsimple quality assurance / quality control (QA/QC) system for samples and assays, with a response process to react to out of specification resultsconsistent method of exporting, visualising, processing and interpreting assay data to create mining blocksdevelopment sign-off system so that all development and stoping is controlledproduction tracking system to monitoring and reporting what ore and waste volumes have been moved from the face, to any intermediate stockpiles, the run-of-mine (ROM) pad and into the crusherreporting system for daily, weekly and monthly reporting of tonnes and gradesdocumentation so that the grade control system has simple, but effective descriptions of how it works, who has responsibilities, and authorities, and be easily maintainedreconciliation system to compare resource and reserve to grade control and to mined and milledtraining system so that the geology team can quickly become competent.In this paper, the authors discuss the requirements of each point, and comment on common shortfalls observed by them over several years’ experience on producing mines worldwide.CITATION:Rose, S and Fahey, G, 2014. Modern mining geology, in Proceedings Ninth International Mining Geology Conference 2014 , pp 461–466 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

Many young mining engineers do not consider consulting as a possible job, believing that many years of working on-site is required to achieve practical experience, develop expertise and acquire industry contacts. However, mining consultancies employ engineers with varying levels of experience, including part-time university students, graduates and engineers who are relatively new to the industry. This paper outlines the role of a young engineer in a large mining consultancy and the benefits to both the consultancy and the client of having a mix of consultants with a diverse range of experience. From the authorÆs perspective, the work experience, lifestyle and rewards of mine consulting are compared to site based work, including a discussion on whether consulting is able to offer the professional development that a young engineer needs.

Jan 1, 2009

By Grano S. R, Lauder D. W

Investigations on the oxidation behaviour of chalcocite and its rejuvenation by hydrogen sulphide ion have been undertaken. Chalcocite oxidation was measured using X-ray photoelectron spectroscopy (XPS), zeta-potential and by dissolution in et

Jan 1, 1997

By G R. Hancock, S Grant, T Whiteside, J B. C Lowry, J Boyden, T J. Coulthard

Physically-based landform evolution models (LEM) provide a spatial framework to forecast the long-term geomorphic stability of post-mining landscapes. When used to test the relative stability of different landform designs, LEMs may assist with the development of optimal closure designs for rehabilitated mines. However, in order to reduce prediction error, factors controlling landscape evolution must also be accurately represented by models. This requires that the correct sets of processes are represented and that driving parameters used in LEMs are, if necessary, calibrated to the landscape of interest.Vegetation exerts strong controls on the hydrologic and geomorphic processes that drive landscape evolution. Hence, the spatial and temporal scales over which typical patterns in vegetation are represented in different landscapes are important considerations in LEM calibration. However, vegetation is rarely accounted for in LEMs and even when integrated is often represented simply, without representing spatial dynamics of vegetation cover that may impact landform development.This study focuses on characterising vegetation patterns to calibrate a new vegetation module of the The Cellular Automaton Evolutionary Slope and River (CAESAR)-Lisflood LEM to be applied to a conceptual rehabilitated landform of the Ranger uranium mine located in the Alligator Rivers Region (ARR) of northern Australia. In the ARR the spatial dynamics of vegetation over time are largely driven by monsoonal rains and topography. Extensive dry season fires are also common in the region, temporarily reducing vegetation cover where they occur. Hence, hydrology, topography and fire disturbance interact to shape a distinct, yet dynamic, mosaic of different vegetation types of varying cover density. As a basis for calibrating the new vegetation function, the distribution and dynamics of vegetation are characterised for this savannah landscape by remote sensing, in conjunction with ground data.CITATION:Boyden, J, Lowry, J, Coulthard, T, Whiteside, T, Hancock, G and Grant, S, 2016. Accounting for vegetation dynamics in landform evolution modelling, in Proceedings Life-of-Mine 2016 Conference , pp 63–66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By T Wang, D Wang

Photogrammetry-based techniques supported by traditional mapping tools are more frequently used for open pit geotechnical mapping. It fundamentally involves the collection of geological, structural and rock mass data from pit batters when safe to do so. These are essential components for refining and implementing continuous improvements to geotechnical models. The geotechnical model is used to review bench performance, optimise geotechnical design parameters, interpretation and analysis of pit slope stability. This paper is a case study of implementing different pit mapping methods at Mount Carlton gold mine, North Queensland. It critically reviews the tools required, including the Brunton compass, mobile application Clino, geotechnical data mapping software CloudCompare (2015) and Sirovision software. The review compares the image precision, structural measurements and data analysis. The review also underlines mine site management philosophy for safe geotechnical data collection to identify in-pit geotechnical hazards and the mitigation of potential slope instability. Sirovision is a remote sensing system for site geology mapping and interpreting geotechnical characteristics of exposed mining faces. The system utilises off-the-shelf digital SLR cameras to capture stereo photographs of the rock face and uses the latest image processing technology to generate accurate 3D models. These 3D models are digitally analysed using computational geometry to extract unbiased and accurate geological and geotechnical data. CloudCompare processes high accuracy 3D dense cloud rock surfaces reconstructed with photogrammetry software to extract the geological planes using the FACET or Compass plugins. The major discontinuity sets can be observed and the orientation (dip/dip direction) obtained from the algorithm is accurate and reliable for geotechnical assessment, including kinematic and rock slope stability analysis.

Nov 29, 2022

By B Y. Luan, Y Tian, W Zhou, X Lu, Q X. Cai

The unmanned driving technology in open pit coalmines is an important technology that relies on innovation to drive the development of the open pit coal mining industry in China’s transformation of growth drivers and industrial structure upgrading. It is an important path to solve the shortage of mine truck drivers in the future mining, an important way to improve the working environment of open pit mining personnel, and an important foundation for achieving flexible production capacity in open pit mining to cooperate with the coordinated development of new energy. The communication rules at intersections are key to ensuring the safety and efficiency of unmanned driving in open pit coalmines. This paper proposes a collaborative traffic strategy between unmanned trucks for the single bucket unmanned truck intermittent process system in open pit coalmines. Based on the gap theory, this paper analyses the conflict characteristics and establishes a coordinated traffic strategy for the common intersection and merging conflicts of unmanned truck trucks in open pit coalmines, A multi-agent system simulation platform was built to evaluate the coordinated traffic efficiency under different initial average gap sizes of vehicles, with intersection traffic density, vehicle speed, and gap changes as key indicators. The results show that under the simulation conditions of this article, when the initial average gap of vehicles reaches three (four) times or more of the safe distance, the coordinated traffic performance of intersection conflicts (merging conflicts) is better, and the traffic capacity of intersections is close to the traffic capacity without conflicts.

Sep 1, 2024

By P Craig, I Canbulat, J Naylor, J Emery, A Sykes

Longwall mining is by far the most common method of underground coal extraction in Australia. Industry trends and expectations are placing increasing emphasis on the reliability and productivity of these operations. Longwalls are becoming wider and longer while retreat rates are continuously increasing due to significant improvements achieved in longwall equipment reliability and automation. This increased longwall productivity is placing significant emphasis on the reliability of longwall panel development.Although there have been significant improvements in the reliability of continuous miners and hydraulic drill rigs, the traditional resin-encapsulated bolt installation is still the principal method used in all major coal producing countries around the world. Anglo American realised that an opportunity existed to introduce an alternative roof bolt installation technique called ‘spin-to-stall’ (STS) into Australia. STS was first introduced by Anglo American Coal in South Africa, where it has been successfully used for over a decade, though implementation of South African STS resin in Australia has proven to be near impossible. Therefore, a new STS development project was initiated between Anglo American Coal and Jennmar Australia. This paper summarises the journey of this project, the results achieved and the successful implementation of STS at Grasstree mine.CITATION:Emery, J, Canbulat, I, Craig, P, Naylor, J and Sykes, A, 2014. Development and implementation of spin-to-stall resin at Anglo American’s Australian Underground Coal Operations, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 287–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

In 1948, it became clear that the ventilation system of The Zinc Corporation Limited and New Broken Hill Consolidated Limited mines, would be inadequate for future operations. The,paper describes in detail the process of designing an entirely new ventilation system for a large underground mining operation. The system was based on a single new upcast airway to be located on the boundary of the two properties, which were to be ventilated in parallel as two separate ventilating districts.From calculations of resistance, and assessments of future air requirements, the duties of a new exhaust fan to be located on the collar of the upcast airway were specified as 700,000 cubic feet per minute at 2·6 in. w.g. total pressure for initial operation in 1953 increasing to a maximum of 900,000 c.f.m. at 3·6 in. w:g. total pressure ten years later. The economic size of the new airway was calculated from a consideration of the first thirty years operation of the system, and it was decided to provide a 20 ft. diameter concrete-lined shaft.The new system went into operation five years after the initial planning, and the effect of the difference between actual and predicted rates and distribution or production are discussed. The final result was entirely satisfactory.INTRODUCTIONThe first proposal for an investigation of The Zinc Corporation Limited-New Broken Hill Consolidated Limited ventilation system with a view to putting it on a proper technical basis was made in 1938. A new Main Shaft was then being sunk, and it was decided to postpone the enquiry until this had been completed to No. 14 Level, when operations would be temporarily suspended and the shaft commence to operate as a major airway. The investigation was completed early in 1940, when Z.C. Ltd. upcast fan was...

Jan 1, 1956

Japanese pig iron production in 1973 registered about 90 million tons. As clearly seen from the productivity (2.04 t/m3/D), and fuel ratio (494 kg/t-pig), the Japanese steel industry has maintained quite high levels of efficiency in blast-furnace (BF) operations. Among the many factors which have contributed toward these high levels of efficiency, the use of high quality coke is very important. The Japanese steel industry imports about 85% of its metallurgical coals from various countries of the world, including Australia. The effective use of these metallurgical coals of various origins in accordance with their re- spective properties is most essential for maintaining coke quality. This paper describes coking properties of various metallurgical coals and blending techniques based on these coking properties, in relation to the specifications of coke quality required for efficient BF operations. This paper also describes briefly new technology for expanding the scope of the use of coking coals.

Jan 1, 1975

By Mogi G, Akaike A, Yamaguchi U

A new algorithm has been investigated for three-dimensional open pit designs to improve the dynamic cone approach which utilises the dynamic programming technique. The conventional dynamic cone method was improved by introducing examination processes: 1. whether any negative blocks are included in a unit cone or not; and 2. whether it is possible or not to leave the negative blocks unmined in the unit cone without disturbing the geometric condition imposed on the slope angle of the cone. The newly developed algorithm was applied to a large-scale open pit copper mine in a planning stage and the results have been compared with those obtained by the conventional methods.

Jan 1, 1995