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This paper discusses some topical issues on the mining administration and legislation fields including:  1. Licensing û Administration and associated specialist functions including:Processing and volumes of mining privilege applicationsFuture organisation and possible decentralisationSpecialist staffFacilitiesGuide to the Mining Act 1971 2. Mining Amendment Act 1981 Transitional procedures 3. Planning Tribunal First hearing of objectionsPoints of principle resulted there from 4. Quarries and Tunnels Bill Currently before Parliament û implications for metallurgical mining

Jan 1, 1982

By Jarvis ST

Colliery spoil is the major constituent of colliery spoil 'rockpaste' which has been used to infill abandoned limestone mines in the West Midlands of England since the early-1980s. The other constituents of rockpasle are pulverised fuel ash, lime and water. A key property of the rockpaste is its ability to flow within the mine workings over considerable distances before setting. This paper describes the work carried out to identify suitable sites as sources of colliery spoil for making rockpaste and goes onto consider the flow properties of the material and the monitoring methods used on-site. A full-scale trial comprising mulling a 6600 nt' section of an abandoned mine was conducted prior to the mulling of the Littleton Street Mine which had a volume of about 500 000 m'. As well as describing the methods used for monitoring the movement of rockpaste material, a description is also given of a dip-meter developed specifically for the purpose of measuring the level of paste in the mine. This paper shows how a colliery spoil based paste has been successfully rued for infilling abandoned mine workings. The monitoring systems developed for use in the two case studies presented in this paper are now being used extensively for infilling other abandoned mine workings. To-date over I I mines with a total volume exceeding two million cubic metres have been backfilled.

Jan 1, 1998

By J Kuva, M Parian, B I. Pålsson

One of the main factors affecting the suitability of an ore for autogenous grinding is the ore’s competency, ie providing enough critical stones for the grinding process. Several experimental test routines exist and are used for assessing the viability of the ore for autogenous grinding. However, very little attention is given to the generation of fatigue in large stones experiencing repeated shocks in the mill. To investigate this, large pebbles sampled from an industrial autogenous grinding mill running hard and soft ores were categorised based on the grinding energy. From the pebbles, small drill core samples were prepared and went through a series of fatigue cycle tests. Both hard and soft ores showed similar average resistance to failure in compression tests, but the hard ore had a consistent resistance with lower variations. The cores were scanned by XCT before and in-between fatigue tests at the highest reachable resolution, 1.5 µm voxel size. The outcome showed that a higher number of micro-cracks were visible in the soft ore compared to the hard ore. The frequency of micro-crack development in the soft ore may be the reason for its lower specific grinding energy compared to the hard ore. It is obvious that for realistic conditions in an autogenous grinding mill, stones are pre-weakened by fatigue before they fracture. Therefore, shortcut methods focusing only on running tests on fresh and small samples may operate in unrealistic conditions by ignoring the fatigue phenomenon. This is even more important for ores that are on the borderline to be considered as competent for autogenous milling.

Aug 24, 2022

By W D. Erskine, M J. Saynor

Ranger Uranium Mine, surrounded by Kakadu National Park is located in the Alligator Rivers Region (ARR) in the wet-dry monsoonal tropics, 250 km east of Darwin, Northern Territory. A trial landform (TLF), measuring approximately 200 m by 400 m (8 ha) was constructed during late 2008 and early 2009 by Energy Resources of Australia (ERA), adjacent to the northwestern wall of the tailings storage facility at the Ranger Mine. A collaborative research program involving the Environmental Research Institute of the Supervising Scientist (eriss) and ERA, has been underway to measure long-term (five to ten year) rainfall, run-off, sediment and solute losses, seepage and vegetation establishment on the TLF (Saynor et al, 2012; Lowry et al, 2014). This paper reports on bed load losses from four erosion plots built on the TLF. These were achieved by physically isolating approximately 30 × 30 m areas from the surrounding landform on three sides with sidewalls along with an open polyvinyl chloride (PVC) pipe on the downslope side. Each plot was instrumented with a range of sensors. Two plots, 1 and 2 were constructed on waste rock material, while plots 3 and 4 were constructed on waste rock mixed with approximately 30 per cent lateritic material. Plots 1 and 4 had tube stock planted in early 2009, and plots 2 and 3 were initially planted by direct seeding in July 2009 and were infill planted with tube stock in January 2011.CITATION:Saynor, M J and Erskine, W D, 2016. Bed load losses from experimental plots on a rehabilitated uranium mine in northern Australia, in Proceedings Life-of-Mine 2016 Conference , pp 168–171 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By R G. Moreby, S Bluhm, FávonáGlehn, C Pascoe

Resolution Copper Mine in Arizona, USA, is planned to be a 2000 m deep panel cave mine with virgin rock temperatures exceeding 80¦C in rock with high crystalline silica content, resulting in a very challenging ventilation and cooling system design. This is one of the largest copper orebodies ever found and, with a planned rock production rate of 120 kton/day. The project is currently in its prefeasibility phase and the paper discusses features of the ventilation and cooling system design which includes multiple ventilation shafts with total primary ventilation flow of about 3000 m3/s and both surface and underground refrigeration plants producing more than 140 MW refrigeration capacity. The cooling system features large surface bulk air coolers chilling all downcast air supplemented by an underground secondary air cooler system and a chilled service water system. This will be a very challenging mine to ventilate and cool but this work has demonstrated that it will be technically achievable with the application of existing technology.CITATION:Bluhm, S, Moreby, R G, von Glehn, F and Pascoe, C, 2013. Life-of-mine ventilation and refrigeration planning for Resolution Copper Mine, in Proceedings The Australian Mine Ventilation Conference , pp 125-138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By R Barritt

Remedial options for a waste rock dump (WRD) were considered as part of closure planning studies at an active mine in Western Australia. To minimise the impact of any seepage from the landform it was determined that placement cover system utilising the moisture ‘store-and-release’ concept was appropriate. The purpose of the cover system was to:•Reduce net infiltration of meteoric water to attenuate peak concentrations for contaminants of concern in natural receptors to levels that can be assimilated without adverse impact to the surrounding ecosystem; •Provide a growth medium for establishment of a sustainable vegetation canopy; and •Improve current quality of surface water runoff from waste storage areas.The project comprised several phases of work: materials characterisation, numerical soil-plant-atmosphere (SPA) modelling and finally cover system construction and monitoring equipment installation.CITATION:Barritt, R, 2018. Conclusions from long-term cover system performance monitoring – a case study, in Proceedings Life-of-Mine 2018, pp 101–105 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By M Rafty, A Markham, S Atkinson

Australia contains some of the most productive mining areas and is characterised by ancient landscapes and highly variable hydrology. Historical mining of iron ore, coal and other minerals has targeted ore deposits located above water tables, and elevated above creek lines where possible to reduce cost. The downturn in mining caused by falling ore prices over recent years has triggered a drive to reduce cost, maximise yield and delay capital expenditure associated with opening new mines. So as the ore deposits with more favorable mining conditions become depleted there is an increased focus on mining ore associated with valley floors and creek lines. This is demonstrated by a regional assessment of the extent of Channel Iron Deposits (CID) and Iron Ore (Fe) Mines and Deposits in the Pilbara Region of Western Australia (Figure 1). A large proportion of these mines are, or plan to, target high grade CID ore associated with existing creek systems. Figure 2 shows outcropping and inferred sub-cropping CID extents, which suggests there are vast quantities of CID ore deposits throughout the Pilbara Region, intersected by major creeks which could be mined at some point in the future using creek diversions (Atkinson et al., 2017). A similar picture could also be produced for coal mining in Queensland, particularly in areas such as the Bowen Basin.While creek diversions provide an opportunity to maximise the utilisation of these orebodies and extend the life of mine, creek diversions can involve substantial financial, social, environmental and regulatory risks that need to be carefully managed (Markham et al., 2017, Atkinson et al., 2017). This paper discusses the key issues and opportunities associated with diversion decision making. It highlights the importance of using a well-structured assessment methodology that allows key stakeholders to be part of the assessment process and is complementary to material presented in Atkinson et al., (2017). Design considerations for operational and closure designs are presented, as well as mine planning considerations, risks, cost saving opportunities and the benefits of an integrated approach to design. The role technology plays in diversion design and performance monitoring is discussed as are the potential opportunities for the future.CITATION:Atkinson, S, Markham, A and Rafty, M, 2018. Diversion decision making with an integrated approach to design for operations and mine closure, in Proceedings Life-of-Mine 2018, pp 74–79 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By J Wen, P Hou, W Yu, M Hu, Z Jiang, C Bai

Vanadium titano-magnetite (VTM) is one of the important iron ore resources in the world. High viscosity and low fluidity are the basic characteristics of hot metal containing vanadium and titanium during the ironmaking process. Clarifying the influencing mechanism of the melt viscosity would be a significant issue for the high efficiency smelting of VTM. In this paper, a self-developed melt viscometer based on the principle of torsional vibration theory was employed to measure the viscosity of hot metal accurately. Simultaneously, the thermodynamic calculations and some modern detection methods were also used to investigate the precipitation behaviour of high-melting-point phases in hot metal containing vanadium and titanium. The measuring results show that the viscosity of molten iron gradually increases with the increase of titanium content when the mass fraction of titanium is between 0.09 wt per cent – 0.50 wt per cent. Meanwhile, the viscosity of the hot metal was affected significantly by the vanadium content. When the vanadium mass fraction was higher than 0.30 wt per cent, the viscosity of hot metal increased sharply, which will have a serious impact on the fluidity of the hot metal. Furthermore, it was revealed by thermodynamic calculations that an increase in titanium and vanadium content would result in the precipitation of high melting point phases such as TiC, TiN, VC, and VN in the molten iron, ultimately resulting in a decrease in its fluidity. Meanwhile, it was confirmed by Scanning Electron Microscope (SEM) observation that the precipitates in the hot metal were compounds consisting of V, Ti, C, and N elements, which agrees well with the thermodynamic analysis results.

Aug 21, 2024

By B Cook, M Karakus, J Light, E K. Chanda

The aim of this research is to develop a model through which the appropriate paste recipe parameters, for example solid content and cement content, can be derived given the stope specific requirements such as stope dimensions, required strength and curing time. A large number of samples and uniaxial compressive strength (UCS) tests were conducted at the Angas Zinc Mine (AZM) paste plant and testing facility. Samples were varied in tailings solids content, cement content and sand content. The results of this testing were modelled to determine the UCS relationship to each of the parameters. The output of this modelling was an easy-to-use program that outputs the design mixture given the stope dimensions and required stope backfill-curing time. This allowed flexibility within the mining schedule for curing times of cemented paste backfill stopes. The optimised schedule using the stope specific mix design, when compared to the standard 14-day curing time used previously, resulted in a smoother weekly mine production schedule. For the modelled 12-week period (one quarter) the 14-day curing time would result in an eight-day shutdown of the mill. The cost for each shutdown is in the order of $125 000/d. Due to the unique nature of each mine’s tailings, this exact outcome would not be directly applicable to another paste fill site. However, the process in this report could be followed for another site to achieve a system similar to the output of this project. This would ultimately lead to a more optimised backfill and stoping cycle and a more optimised mine.CITATION:Chanda, E K, Karakus, M, Light, J, Cook, B and Harris, A, 2014. Optimisation of the paste fill cycle at Angas Zinc Mine, Strathalbyn, South Australia, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 259–264 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

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

An intensive safety campaign at Mount Isa Mines Limited from 1956 to 1966 saw the lost time accident frequency rate fall to half its original level. A review of the safety programme was carried out in 1967 and in 1968 the Five Point Safety System was introduced. The seven years since its introduction have been years of significant achievement both in production and safety. Improving safety is a fundamental part of Mount Isa Mines Limited's policy and this system has been a major tool in implementing that policy. To be successful personnel need to be prepared and trained for its introduction and subsequently counselled on its use. A carefully prepared programme is required to phase in various aspects of the system and to make use of complementary steps. The system has been a success and it is anticipated that the continued drive to improve the use of principles of the system will further improve safety. It is hoped that this paper will be of value to those personnel concerned with industrial safety in Australia.

Jan 1, 1975

By D J. Williams

The majority of surface tailings storage facilities continue to employ sub-aerial tailings slurry deposition. Surface TSFs are typically sized and operated in a way to minimise the initial capital cost of the facility, driven largely by the net present value approach to accounting. This generally leads to too small a storage, too fast a rate of rise of the tailings, and difficulties in managing supernatant water. In turn, this results in wet and soft tailings deposits of high moisture content and low density, and the need for frequent and costly tailings dam raises. Further, such tailings deposits often do not facilitate closure and rehabilitation of the facility. Globally, there are on average over two failures annually of such tailings dams, resulting in loss of life, damage to infrastructure and environmental impact downstream, and the loss of company shareholder value and reputation. Recent high profile tailings dam failures are threatening the mining industry’s financial and social licence to operate.Among the physical processes that tailings undergo on sub-aerial deposition are beaching, hydraulic sorting down the beach according to particle size and specific gravity, settling, consolidation, and desiccation on exposure to the sun and wind. Beaching and hydraulic sorting have proved difficult to test at laboratory scale and difficult to model, and are best assessed in the field. Settling, consolidation and desiccation may be assessed at laboratory scale, but to date there has been an absence of tests to form the basis for the design and management of tailings deposition, and ultimate closure and rehabilitation. The paper describes recent advances in tailings testing methods, including a purpose-built slurry consolidometer that tests the settling and consolidation of tailings from a slurry consistency, simulating increasing tailings depth to about 50 m; and a purpose-built instrumented column that tests the settling, self-weight consolidation and desiccation of a surface layer of tailings, also from a slurry consistency. Selected test results from these two apparatus are presented in the paper, together with brief descriptions of how they may be used to better design tailings slurry deposition. In addition, planned further advances in tailings testing methods are briefly described.CITATION:Williams, D J, 2018. Recent advances in tailings testing methods, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 8–37 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By O N. Savassi

A rigorous methodology for prediction of flotation plant performance is presented, which is based on a standardised batch flotation test called the MFT. The work is part of the FLEET program, developed by MinnovEX with the support of seven large mining firms. The methodology is divided into three key steps: direct measurement of the kinetics of true flotation in the pulp, independent of hydraulic entrainment and other froth effects in the batch cell; benchmarking of the industrial plant over a broad range of ore types and operation conditions; and model calibration to describe froth effects in the plant, with a minimal number of parameters. To date, the methodology has been applied with success at several industrial plants, encompassing copper, gold, nickel, iron, lead, zinc and coal operations. This paper includes a description of the laboratory testwork procedure and scale-up to full industrial circuits. Examples of industrial application are also presented.

Jan 1, 2005

By M J. Nimmo

extremely powerful tools for building predictive and generative models. ML can be used for building highly accurate regression and classification models. But without careful data science and statistical analysis, a regression or classification model could be highly biased and completely wrong – and we may not even realise. An example rock density estimation task will be used to illustrate the potential gains and possible pitfalls in using ML and AI in Mineral Resource estimation. What could possibly go wrong? Nothing! For most simple regression or classification problems, very little. For density estimation, using the global mean may be all that is possible, but the resource classification would need to reflect the uncertainty in global estimation of tonnage. Everything! From data collection and measurement, from selecting ML and AI techniques and designing the analysis workflow to our own cognitive bias. The things that could go wrong are vast and may include but not limited to asking the wrong question, not asking questions, data bias, measurement errors, insufficient data coverage, not collecting the right variables, not collecting enough observations, collecting clustered samples, unbalanced data, filtering out data without reason (outliers), clipping data (outliers), relying on automatic feature selection, including irrelevant variables, excluding relevant variables, geological interpretation, changing context, blindly following best practice, splitting small data sets, subsetting large data sets, using the wrong tool for the task, insufficient budget to complete the analysis, not allowing enough time for testing and experimentation (the science), focusing too much on building the model (the engineering), not learning from the data, our assumptions, our preconceptions, and our skill. This paper will explore the question of how training regression models to predict rock density are affected by gaps in the data (missing observations and missing variables). What could possibly go wrong?

May 24, 2023

By D Wyborn, P A. Dowd

The characterisation of rock fracture networks is an important component of rock engineering applications involving stability assessment or fluid flow analysis. However, the derivation of a reliable rock fracture model remains a very challenging problem in practice. This paper describes a Bayesian framework, in the form of Markov Chain Monte Carlo (MCMC) simulation, for the construction of such a model. Model conditioning using different data sources is discussed including seismic events recorded during hydraulic fracture stimulation, rock face fracture mapping data and downhole geophysical survey data. The freeware FracSim3D is used for the simulations.

Sep 26, 2011

By Y Shougu

Many mine accidents will affect the mine ventilation system when they occur. At present, there is a lack of monitoring means to capture the occurrence of accidents in time by monitoring the ventilation system, so as to take emergency measures to reduce the loss of personnel and property. Pressure wave is an elastic wave existing in air. Most accidents in mine will cause obvious changes of pressure wave. It is an innovative idea to monitor the occurrence of accidents in mine by measuring pressure wave. The development and functions of the pressure monitoring device and related software are introduced in detail. The pressure wave monitoring test is carried out in San Xavier underground mining laboratory, and the D-wave and S-wave waveform data are collected. The waveform characteristics are analysed, and the main frequency distribution of the pressure wave is found to be within 1 Hz by using FFT. At the same time, the influence of the propagation distance of the pressure wave on the waveform is analysed. The propagation velocity of D-wave and S-wave are roughly calculated, and they are 279.6 m/s and 397.3 m/s respectively. S-wave is slightly faster than D-wave. Although there are errors and uncertainties in the test, the test verified the feasibility of the existence and collection of pressure waves in the ventilation roadway, and provides a method for the future study of the propagation of pressure waves in the mine ventilation system.

Oct 12, 2022

In classical drill and blast underground mining methods, especially narrow vein operations economic quantities of broken ore can be left behind following normal mucking operations on the stope floors. The ore left behind can have significant economic value and if not collected can be lost forever. This paper reviews techniques for cleaning this material from stopes that have been used in the past and reviews possible modern techniques that can be applied to ensure this valuable material is removed from the stopes.

Aug 1, 2010

By B E. De Gee, N Viviers, A Naidoo

In 2013 the Mopani Copper Mine Mufulira plant in Zambia embarked on a project that was aimed at improving concentrator recoveries. The project commenced with the automation of the milling and flotation circuits. This involved the installation of new instrumentation, namely measurement devices and actuators, and the connection of these to new programmable logic controllers (PLCs).The infrastructure changes were followed by the implementation of basic proportional-integral-derivative (PID) controllers on the PLCs. Supervisory control and data acquisition (SCADA) interfaces were also implemented to allow for switching between controller modes, inputting of setpoint variables and to provide a visual display for process monitoring. The final phase of the project involved the installation and commissioning of advanced process control (APC) solutions on the milling and flotation circuits. This work was carried out by Mintek over 21 on-site days. The APC solutions included the MillStar and FloatStar suites of advanced controllers.The MillStar control suite focused on stabilising the mill feed and mill discharge on the two primary mills as well as the flotation circuit feed. Mintek’s CyLas instruments, which provide a measurement of the hydrocyclone underflow angle, were also installed. The measurements were incorporated into the discharge stabilisation control on both milling circuits. The FloatStar level stabiliser controller provided flotation cell pulp level control on fourteen cells, including two columns.Performance tests showed that the Mintek APC system stabilised the mill feed and mill discharge while ensuring the process remained within operational constraints. The MillStar control system utilised the CyLas instrument to prevent roping on the hydrocyclone underflow. This was not always achieved under normal operation. Additionally, the flotation section was stabilised as a result of improved level control by the FloatStar control system.Performance comparisons showed that the Mintek control system improved the operation of the milling and flotation circuits resulting in a greater copper recovery.CITATION:Naidoo, A, De Gee, B E and Viviers, N, 2014. Implementation of an advanced milling and flotation control system at Mopani Mufulira copper mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 363–368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By Q Shu, T Deng, B Yan, B Song, D Wang

In view of the lack of phase equilibria data of vanadium-bearing oxide system and the desirability of them for design or optimisation of vanadium extraction process, the phase equilibria relationships of V2O3-FeO-SiO2-CaO(15 mass per cent) system were determined experimentally and then an isothermal section phase diagram of this system was constructed. Totally, 81 samples of different composition were equilibrated at 1623 K for 48 hours in iron crucible under Ar atmosphere. The equilibrated samples were quenched quickly in cold water, and then the phase constituents of all the samples were identified by X-ray diffraction (XRD) combined with electron probe microanalysis (EPMA) measurements.

Aug 21, 2024

Located 350 km west of Sydney and 20 km outside Orange, NSW, lies the Ridgeway Gold Mine û NewcrestÆs flagship Underground Gold Mine. Key to success at Ridgeway has been the fast tracked development of the 3.8 km, 1 in 5.3 conveyor decline which houses the 850 t/hr conveying system feeding the dedicated Ridgeway Concentrator, built adjacent to the existing Cadia Hill Concentrator. Eroc was contracted to develop the steep conveyor decline, drawing on its personnel and experience from past metalliferous, tunnelling and coal mining projects to complete the ambitious schedule within 12 months. This paper deals with the complexities and experiences in safely delivering what is understood to be one of AustraliaÆs steepest declines of any substantial length in a metalliferous mine.

Jan 1, 2002