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By L McCallum, G Dale, B Silverwood, T Roscoe, A Costin

The introduction of Progressive Closure and Rehabilitation Plans (PCRPs) in Queensland from 2019 places greater importance on planning and implementation of mine rehabilitation activities. The progress and outcomes of progressive rehabilitation activities is monitored and reported upon to demonstrate success in achieving progress towards the approved post-mining landform, and to inform corrective action where required. The requirements of PCRPs place additional emphasis on mine sites to quantify the risks of successfully achieving planned outcomes. This is particularly challenging given mined-land rehabilitation is a complex process involving decisions on multiple inter-acting management interventions, climatic conditions and spatially variable site characteristics.

Aug 2, 2023

"Cash flow modelling during project evaluation is enhanced when probabilistic methods are applied to the inputs. One of the important inputs is the quarterly production profile. Typically, the steady-state production profile provided to project evaluation practitioners is deterministic, with each quarter the same as every other quarter. This is unrealistic as actual production profiles from existing mines exhibit a range or quarter-on-quarter variance. Monte Carlo stochastic simulation of the production profile can be used to provide a range of possible outcomes, but how are these ranges selected? This paper describes the use of quarterly production variance from a large database of mines worldwide as a benchmark to inform the appropriate selection of ranges. The coefficient of variation is used to rank the production from mines, with quartile analysis applied to indicate industry best, median and worst variation. Due diligence of existing mines and evaluation of future production performance can be quantitatively assessed using this approach. Examples of the effect on value are provided.CITATION:Stewart, C A, 2016. Production variance benchmarks and their use in project evaluation and due diligence, in Proceedings Project Evaluation 2016, pp 201–213 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By B Murphy, N Strong, J Albrecht

Rio Tinto’s Argyle Diamond Mine has a history of underperformance with delivery of ore from the underground operation to the surface for processing with no real clarity in sources of loss and value. In order to increase underground production performance, the basic concepts of the Theory of Constraints model were applied to the Argyle underground production system. This prompted a revised view on bottlenecks and contributors to value loss and ultimately leading to record breaking mine performance. System loss reporting to demonstrate the best opportunity to drive value, departmental detail to develop tools to identify improvement opportunities and clarity across the team to ensure alignment and clear lines of communication were critical to the project success.

Mar 15, 2021

By Chaves AP

This paper describes an investigation on the surface properties and mechanisms involved in the agglomeration of iron ore. For this purpose, an organic binder (carboxyl-methyl-cellulose (CMC)) was used in substitution of bentonite, the classic binder in iron ore concentrate agglomeration. Recently, a renewed interest of the iron ore producers in Brazil to replace bentonite for an organic binder, because of the economy that can be achieved in the, blast furnace operation. These savings are mainly due to the lower aluminum silicate addition which decreases slag volume and the improved pellet metallurgical properties which have the potential for lowering hot-metal production costs. Also organic binders are effective at lower addition levels, which results in lower storage and transportation costs. It is very important in Brazil because of the vast geographical area since transportation is made mainly by truck. Another advantage of organic binders is that they have low ash contents, and therefore most of the binders bum. off during the pellet firing operation. Previous studies have demonstrated the possibilities of the use of CIVIC, but in addition to its high cost, the pellets presented improper behavior at high temperatures or when prepared with high moisture levels. In the investigation here described, these problems have been solved through the addition of other reagents to CMC.

Jan 1, 1993

Gunpowder Copper Limited processes 1,000 tonne/day of Mammoth ore in a conventional flot- ation concentrator. Run of mine ore is prepared for flotation by three stages of crushing and two stages of ball milling. The concentrate, in which the primary copper mineral is chalcocite, is solar dried and exported to Japan. The history of operation is summarised, and plant practice and metallurgical problems are discussed.

Jan 1, 1974

By Thompson AG, Cadby GW

The New Austrian Tunnelling Method (NATM) is a proven concept for the safe and economic construction of underground facilities. This is especially true for tunnelling activity where changing ground conditions are often encountered. However, the principles central to the NATM have gained only limited use within Australia, presumably due to the measurement process inter- fering with tunnel driving and the cost associated with instrumentation and interpre- tation expertise. The design and operating principles of two basic instruments are explained together with laboratory simulated test results and suggest- ions for use in an integrated NATM style approach to underground excavation and construc- tion. The two instruments monitor load in rock reinforcement and deformation in rock or primary and secondary linings. The instruments may be fitted with a miniature display module which outputs the measured parameter in engineering units directly. The design of the sensing components allows the instruments to be installed in various configurations suitable for routine performance monitoring, quality control, support element testing or detailed investigations. The display module which reduces the need for instrumenta- tion expertise should suit contractors and allow performance data to be obtained which quickly may be used to modify support procedures to suit ground conditions. When complemented by convergence measurements the devices enable most facets of the NATM to be implemented.

Jan 1, 1987

By J Moffatt, T Payten, N Spooner, L Teixeira, L A. Balzan, G Wilkie, G Tsiminis

Fluorine is a penalty element due to its reactive nature. In acidic environments many fluorine minerals dissolve to form hydrofluoric acid (HF), changing processing conditions. When smelted HF can be released, causing negative effects to nearby people and the environment, as well as potentially damaging the smelter. Sale of ore with high fluorine levels elicit a financial penalty or are banned outright. Real-time sensors create the opportunity for instantaneous decisions on ore processing due to changing conditions. A fluorine sensor would allow rises in fluorine concentration in a processing stream to be flagged, and decisions on processing conditions or diversion to stockpile before processing could be undertaken. As fluorine is a light element, it is difficult to detect with in-field XRF devices and does not work well with PGNAA. There are currently no existing sensors to quantify the presence of fluorine in real-time, and thus decisions based on fluorine grade cannot be made at minute- or even hour-scales. Sensors designed to measure the presence of minerals that contain fluorine are a possible avenue to enable the real-time detection of this element. Mineral-based sensing may also give an added advantage of additional information about how the fluorine will react under different processing steps. The authors were given a grant under CRC ORE II (project number P1–005) to search for mineralspecific signatures suitable for real-time analysis. The work focused on novel regimes and applications of fluorescence as a means to detect specific minerals. The aim was to exploit fluorescence responses unique to minerals of interest in mining systems in order to produce sensors that address gaps in existing capability. After the successful discovery of signatures specific to two major fluorine minerals an additional grant (P1–014) was funded to develop the research into a prototype on-belt sensor, in partnership with Scantech International Pty Ltd. This paper details the development of a sensor package through multiple Technology Readiness Levels (TRLs) through collaboration with government/industry grant schemes, academics from university, and a sensor-focused Mining Equipment and Technology Services (METS) company. We give a brief description of the new sensor technique and provide a case study of multi-disciplinary collaboration.

Aug 24, 2022

By D Johansson, A Nordqvist, D Mihaylov, N Petropoulos, M Wimmer

The flowability of the caved rock masses in the sublevel caving (SLC) mining method is of great importance. During the blasting process of a SLC-ring, the caved rock mass in front of the ring is compacted. As a result of this compaction, the mechanical properties of the fractured rock masses change, for example void ratio, angle of internal friction and structure of the compacted material. The changed mechanical properties of caved rock mass and recent blasted material can influence the mobility of the material, which could result in blockage of the flow path of the material. The identification of the involved mechanisms in this process can be done after a series of tests in different scales. However, there is no available equipment for dynamic measurements during blasting, ie velocity and displacement of the burden and in the caved masses. This study focuses on the development and laboratory evaluation of a measuring system that can be installed in a borehole. The first trial was carried out in a pillar, where two blastholes had been drilled (9.5 m) parallel with the drift and two measuring holes (16.5 m) were perpendicular to the drift. Two measuring systems were installed in the measuring holes. Some preliminary tests were carried out to find suitable initiation procedures for the emulsion explosive. Applicability and robustness of the developed measuring system were also evaluated. In addition to these tests, an expandable cement mixture was developed to firmly anchor the measuring systems in the boreholes. The measuring system consists of an anchor, armoured cable in a pulling tube and a protective case. The anchor is equipped with uniaxial and triaxial accelerometers. A potentiometric measuring system for displacement up to 2 m is installed at the end of the pulling tube and connected to an extendable spiral cable. All sensors are connected to a data acquisition system (DAS). Both measuring systems have their own DAS to acquire data in case of failure of one of the systems. The measuring system was tested in laboratory conditions with impact velocity up to 10 m/s. It was proven to be functional and gave reliable results.CITATION:Petropoulos, N, Mihaylov, D, Johansson, D, Wimmer, M and Nordqvist, A, 2015. Design of equipment for dynamic burden measurements, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 493–500 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

The Health Tracking project is one of five projects being undertaken as part of the Minerals Industry Cooperation Initiative (MICI) û a national initiative sponsored by the Minerals Council of Australia. The aim of the Health Tracking project is to assess the practicality of ways to demonstrate the monitoring of hazardous exposures and the occurrence of related occupational illness and disease and development of management systems and strategies at a national level. This second stage of the project will be completed in 2005 and will cover four areas: pilot development of a comprehensive job exposure matrix (JEM) for the minerals industry; development of both proactive and reactive occupational illness and disease metrics; recommendations regarding appropriate health tracking models; and provision of best practices guidelines for management of occupational health. The synergies between these areas will establish the path towards an effective national occupational health surveillance system and the development of effective prevention strategies and policies.

Jan 1, 2005

By G P. W Suyantara, Y Tanaka, T Hirajima, Y Aoki, K Sasaki, H Miki

The effect of sodium sulfite (Na2SO3) on the flotation behaviour of bornite and tennantite is reported in this work. Flotation tests were performed using pure minerals of bornite and tennantite under various concentrations of sodium sulfite at pH 9. The flotation results indicated that sodium sulfite exhibited a depressing effect on the floatability of bornite in the presence of 0.1 mM PAX. However, tennantite remained floatable after the addition of sodium sulfite in the presence of 0.1 mM PAX. The flotation tests using mixed bornite and tennantite confirmed the flotation results of single minerals. Surface characterisation using X-ray photoelectron spectroscopy (XPS) was performed to explain the flotation results. A mechanism is proposed based on the XPS analysis results.

Aug 24, 2022

By N Power, R Hassell, E Jones

Wiluna Mining Corporation are progressively re-entering the old Wiluna underground mining complex. The existing underground was abandoned in 2013 by previous owners and left to flood with water levels reaching above the East Pit portal and Happy Jack Pit portal and up to 300 m below surface in the Bulletin underground. Re-entering the mine commenced in 2017 with dewatering of the Bulletin decline. The underground development had been previously supported with friction bolts, with weld mesh in places. Until mid-2021 rehabilitation requirements were based on an external visual inspection of the installed ground support scheme. However, several incidents involving falls of ground due to corroded bolts have occurred during this time, showing that this approach was inadequate. The challenge the operation faced was should the entire decline be rehabilitated, the implication being not only a large rehabilitation cost but also the impact of severe delays to the mining schedule. The question was asked can the operation better understand the level of corrosion damage and potentially optimise rehabilitation requirements. A proposal to use a systematic approach to assess corrosion by environmental condition mapping, visual external corrosion assessment, and internal corrosion assessment via borehole camera inspections was provided and accepted by Wiluna Mining Corporation. The objective of this work was to produce a three-dimensional map showing the degree of corrosion on the reinforcement systems in the capital infrastructure, this would then be used to risk assess and prioritise rehabilitation requirements. This paper summarises the approach, methodology and results that provided the Wiluna mine planning team with information to enable planning of resources and budget to justify priorities of rehabilitation.

Nov 29, 2022

By R Thompson, D Tulloch

"Wet-weather or 24×7 wet-trafficability is a commendable design objective for unpaved mine haul roads, but practically often difficult to achieve, due both to the road sheeting material selected, and also its breakdown under the action of traffic and environment. Accidents allied to wet-trafficability issues, either due to rain or often more commonly, over-watering of mine roads, is increasing and especially the loss of control or uncontrolled vehicle movements categorisation. The dominant system failure is that once vehicle control is lost, control cannot be regained.The friction supply, or ‘skid resistance’ of a mine haul road sheeting is critical to the safe operation of the road and data has to be collated concerning the variation of friction supply with sheeting material engineering or indicator properties. In the light of the paucity of data existing in this field, this paper presents the contributory research that informs the development of improved and validated unpaved mine road friction supply estimates, based on a number of mine site evaluations across a range of sheeting material types and characteristic parameters, leading to improved predictive models of friction supply.Results from this preliminary review will enable operators to assess their road sheeting materials, improve and validate unpaved mine road friction supply estimates. This will contribute to improved road design, management and 24×7 operability decisions and contribute to a reduction in heavy vehicle loss of control incidents on gravel-surfaced mine haulage roads.Citation:Thompson, R and Tulloch, D, 2016. What's Stopping You? The Role of Sheeting Material Selection in Safe Haulage Operations, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 253–264 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By T Walkemeyer, R Elliott, D Chang-Martin

Over the past decade, discrete element method (DEM) simulations have seen increasing adoption by the resources sector to inform the design of materials handling equipment such as transfer chutes, bins and hoppers. But, if ‘all models are wrong, but some are useful’ (Box, 1979) what approaches are available to check that a DEM simulation is useful? How to avoid garbage in equals garbage out. This work considers what properties of bulk solid flow behaviour are important to transfer chute simulation. Cohesive bulk solids (such as sticky iron ore fines) can develop sufficient strength to form a stable cohesive arch, this phenomenon is not well predicted by measurements of angle of repose. This work presents a two-part approach to the development of a useful DEM model that can be used to add value to the design and optimisation of bulk materials handling equipment. Part 1 is the calibration of not just one, but a range of material models chosen to envelope the range of anticipated materials that will be handled. This work describes the DEM simulation of a batch of direct shear cell tests to develop material models that can be measured by the same metrics routinely used to characterise the flowability of cohesive iron ore fines. Part 2 of this work describes systematic methods for validation of the transfer chute DEM simulations. The DEM model is only useful if it can adequately represent the typical problems observed within a transfer chute, such as blockages due to build-up and cohesive arching. Proper validation requires good observations. Validation examples of site observations are shown side-byside with simulations to demonstrate the adequacy of the DEM model and calibration approach. DEM simulations have the potential to add significant value by allowing engineers and designers to predict material flow-through equipment based on a range of material properties, allowing for stress testing designs and making iterative improvements.

Sep 18, 2023

There is no doubt that the mining sector is considered to be the backbone of many countries. Furthermore, it has played an important role in the prosperity of nations, whether developed or developing. Saudi Arabia is one of these countries that has a large variety of metallic and non-metallic mineral resources that range in size and value occurrences of limited potential to deposits large enough to sustain profitable exploitation. Therefore, the Saudi government needs to reinforce the capacity of the sectoral institutions to better regulate and promote the sustainable development of the sector. The ability to overcome the administrative and legal complications that constrain private sector participation in the minerals sector, through new mining code which will streamline the procedures for obtaining licenses and will add more predictability and transparency to the application process, are proposed for increasing the sustainable development. This paper will outline how the Saudi government is tackling the major challenges that face the minerals industry. This paper provides the background to the Saudi Arabian mineral sector and its industrial base. Finally, the paper identifies the problems and constraints that face the minerals sector in Saudi Arabia and provides an assessment of the effects of government policies and planning efforts in the minerals sector, particularly during the period of the development plans which started in 1970.

Jan 1, 2009

By D Atheis, S Williams, A Dance, D Taplin

"Resurrected from its former life at the Big Bell operation, the grinding circuit at Evolution Mining’s Edna May operation in Western Australia has many a story to tell. The task of optimising a plant designed for another orebody provides as many challenges as opportunities. Initially faced with a blend of primary and oxide ore, the circuit achieved in excess of 320 t/h until the oxide was depleted, leaving only the much harder primary feed.The 2.0 MW semi-autogenous grinding (SAG) mill and 3.7 MW ball mill were assisted by a 150 kW pebble crusher, but the power limitation of the SAG mill resulted in a drop in throughput. Edna May personnel have been involved in a number of progressive improvements to restore the design capacity of the concentrator and work towards 3 Mt/a or even higher ahead of the gravity and leach recovery circuits.These improvements include: a crush forward configuration of the SAG mill scats partial to full secondary crushing variable speed drive upgrade of the SAG mill lifter and grate design changes ball mill circuit grinding efficiency.This paper summarises the chronology of events that has resulted in significant improvements in throughput by conventional (and in some cases, novel) methods of reconfiguring the existing grinding mills. Lessons learned and hindsight perspectives will be summarised, sharing this educational experience with other operations in a similar situation.CITATION:Dance, A, Atheis, D, Williams, S and Taplin, D, 2014. Grinding circuit improvements at Evolution Mining’s Edna May operation, in Proceedings 12th AusIMM Mill Operators’ Conference 2014, pp 63–70 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 1, 2014

By C McIntosh, M van Dam, N Whetter, R Lane, M McCulloch

Mine geology is understood through synthesising large amounts of structural, lithological, geochemical and geophysical data derived from the original topographic surface, drilling and surfaces exposed and removed during open cut and underground excavations. Computer- generated 3D geological models of any mine environment need to incorporate large amounts of information but also should be regularly updated with typically frequent influxes of new data. Geologists with the local knowledge should also be involved in the model construction, enhancement and interpretation, placing ease-of-use functionality high on modelling software requirements. Implicit-style modelling is a fast-growing area of 3D geological software development where interpolated surfaces such as lithology boundaries and bedding orientations are defined mathematically as functions rather than explicitly through coordinate meshes. The functions are constrained only by the data and not by an artificially imposed grid; therefore, implicit 3D modelling can process a lot of information quickly and routinely operate on original data (such as observed contacts and structural data) rather than on evolved iterations and interpretations. 3D mine geology models can be readily updated with new data, which can be automatically reprocessed to test ideas in near-real time. Implicit, function-based 3D modelling software has been applied to the Globe-Progress mine in West Coast, New Zealand. This structurally- hosted gold mine has some geometrical conundrums that are in part being resolved as excavation of the open pit proceeds. The relationship of the Globe-Progress ore shoots to hanging wall and footwall structure is still not fully understood, however, and 3D geological modelling is assisting with visualisation and testing of structural hypotheses. The modelling is also capable of predicting areas of bedding defect slope failure in yet-to-be excavated parts of the mine.

Jan 1, 2009

The Ore Reserve System implemented at Mount Isa for Mount Isa Mines Limited is a comprehensive' computer system designed to process assay, geological, structural and survey data for Isa and Hilton Mines. This paper outlines the achievements of this system to date and by example, discusses the various reports and plotted output available. __ The impact of the ore reserve system particularly within the-Geology and Mine Plan ning Departments is reviewed in terms of new approaches to ore reserve calculations, evaluating the economics of various mining methods and reviewing preliminary stope designs. The compilation of metal distributions for both copper and lead orebodies at varying cut offs and reducing the involvement of skilled personnel in preparing non-standard plots of borehole paths are discussed. Options available through the system and their applications are outlined together with the planned future development of the system.

Jan 1, 1974

By Laffin N. W

Invariably when a new plant is cammissioned operations personnel on takeover look at ways and means of reducing certain restrictions and improving process conditions. These improvements are generally of a mechanical/engineering nature with minor metallurgical alterations to fine tune and maximise recovery. Most operations are continually reviewing and updating existing equipment and equipment spares to gain the maximum performance hereby reducing operating costs. Design of current carbon-in-pulp/carbon- in-leach (CIP/CIL) plants has evolved to such a high degree that many of the medium sized plants can have a "blue printed" design from one to the next if the same engineering designer is used.

Jan 1, 1989

By Jones KW, McClelland RA, Denholm WT, Taylor RN, OÆShea J

Associated Tin Smelters, Sydney, are developing tin smelting operations in a prototype commercial SIROSMELT plant comprising two furnaces of 5 to 8 tonnes capacity. Features of the plant and its operation are discussed and results of its application to tin slag reduction and high-grade tin concentrate smelting are presented. Development work is still in progress but experience indicates that the technology has potential for lowering the costs of tin smelting and relieving constraints on grade and iron content of concentrate imposed by conventional technology.

Jan 1, 1984

By Cooper P. G

I he Electrolytic Refining and Smelting Company (ER&S) has oper- ated a copper smelter at Port Kembla, NSW since 1908. The feasibility of modernising the smelter was recently studied and external influences were shown to have a substantial impact on the project economics. Profita- bility is determined by the relative magnitudes of treatment charge income earned from processing raw materials and the operating costs incurred. Treatment charges are usually denominated in U.S. dollars and are deter- mined by market forces in the world copper industry. ER&S is no different from other Australian manufacturing industries in that it must maintain its competitive position by controlling costs. The modernisation project seeks to achieve this through new technology and improved labour Productivity.

Jan 1, 1988