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By Hunsaker R. D

The description, characteristics, advantages and application of a new bulk explosive for medium to large diameter dry blasthole conditions is described. A brief outline of the delivery system for the product is also included. This explosive has been designed to provide an alternative to ANFO, currently the most common bulk dry hole product available to the mining and quarrying industry. The selection of the optimum explosive for any blasting operation is of prime importance. It is a major factor contributing to the production of the desired results in terms of muckpile fragmentation, shape and diggability. The optimum explosive can be defined as the most cost-effective in producing satisfactory breakage and displacement of the material. ANFO satisfies this prerequisite for a significant proportion of dry hole applications. This unique, low density and low velocity of detonation explosive has been developed to provide the industry with a cost competitive alternative to ANFO. Typical loading or average inhole densities nominally range between 0.40 g/cc to 0.70 g/cc, depending on the application. Characteristics of this explosive allow for specific and common applications in open cut coal and metalliferous operations. These include ore/waste control operations, prestripping and presplitting applications, sites confronting cap rock problems, and large hole diameter quarries.

Jan 1, 1995

At the treatment plant of the Broken Hill South Limited, Broken Hill, the zinc concentrates, with water, are pumped out to a more or less level area, and stored in dams to dry by drainage and evaporation.In-the construction of these dams a clay bank is first thrown up around the proposed dam site. The concentrate and water mixture are then run in from the perimeter, the solids being continuously shovelled up to increase the bank height, while the clear water is drained off at the centre and returned to the treatment plant.These dams vary in size up to 57,000 sq. ft. in area; when completed the banks are about 12 it. high, and the capacity for the largest dams is about 350,000 cub. ft., say, 20,000 tons.The survey office is called upon for a monthly survey of these dams, generally three of which are in process of building or refilling. The puggy nature of the material prohibits walking beyond the bank of the dam, therefore the following method of estimating concentrates was evolved. No originality is claimed, but as the need is for a true survey, and the results have shown the accuracy of the method, a description is warranted. The dam site is first laid out into 10-ft. squares with a theodoliteand 150-ft. steel tape, the outside lines being placed about 15 ft. from the clay bank - 15 ft. is the maximum convenient distance from the bank for working with the levelling staff mentioned later.As the dam is rarely rectangular in plan, the outside points pegged out are not always the corner of a square, but are placed to give the greatest convenience in later work, that is to say, there may be triangles and irregular figures. The plan (Fig. 1) and photographs (Figs. 5 and 6) will give the general idea of the layout. At each point is driven a 3 ft. 6 in. round iron peg about 3 ft. into the ground. This peg is to permanently mark the point, and is not liable to be...

Jan 1, 1925

A programme began in 1970 to eliminate the charging of fine materials into the copper blast furnace of The Electrolytic Refining and Smelting Company of Australia Ltd. at Port Kembla, N.S.W. A disc pelletiser and drying plant has been installed as part of this programme. Feed material for the plant is a blended mixture of copper concentrates, fine copper-bearing residues, and blast furnace cyclone dust. The operating parameters for the disc have been calculated by comparing the perform- ance of three other discs on the plant. Re- search work on choice of binder, feed moisture and drying conditions has led to the production of reasonably high strength pellets. A description of the pellet plant and modifications necessary to overcome the initial performance problems is given.

Jan 1, 1974

The last decade of national water reform implementation has improved the availability and efficiency of water source allocation in Western Australia. However, it is critical to recognise that the concurrent mining boom witnessed the approach of full water allocation limits, and increasing trends in mineral processing, water infrastructure costs, and wastewater management costs. Water supplies are commonly viewed as absolutely critical to project feasibility in mining, industrial and energy generation projects, even if considered 'non-core business'.   An increasing density of mining projects and industrial estates in Western Australia (WA) creates an opportunity for water infrastructure cost sharing and synergies. The WA government and its agencies have given preliminary consideration to the establishment of independent water utilities in the goldfields (Kalgoorlie), the Pilbara, and Collie regions, and in the Kwinana Industrial Area. The impending Oakajee industrial area and Mid West regional development, and Anketell port in the East Pilbara, could also be considered for common non-municipal water supplies.   The critical issue of apparent commercial risk due to the large scale of water demands and the low customer numbers in the minerals sector relative to other water markets is expected to mandate government partnership in any non-municipal water utility ownership. The commercial feasibility risk is observed as a risk to water supply security for potential mining and industrial customers. Absence of proper water infrastructure planning and governance has the potential to create infrastructure access issues as observed for Pilbara rail developments under the Trade Practices Act 1974.   Other aspects of water cycle management which could be addressed by a non-municipal utility include resumption of mine dewatering water (required changes to WA legislation that are progressing) and consolidated wastewater management for maximising synergy or reuse opportunities and minimising cumulative environmental impacts.   Address of water infrastructure planning for non-municipal water demands must cover commercial and environmental sustainability outcomes to successfully progress minerals sector growth in the State.

Jun 1, 2010

By I M. Platten, Y Xie

Sampling protocols that are designed to suit the mineralisation style will result in a reduction of the nugget effect and hence resource risk. The a priori need for all sampling programs is the effective characterisation of the mineralisation type(s) to support optimisation. This requires a program of sampling for sampling followed by holistic characterisation. At each end of the coarse-gold to fine-gold spectrum, the samplability of a deposit ranges from relatively simple for fine-grained disseminated gold particles, through to extremely difficult for coarse nuggety mineralisation. Many deposits contain a proportion of both particle size types. The proportion and size of coarse gold particles has a direct impact on the effectiveness of sampling, where coarser particles will require larger samples and more specialised protocols. The nature of mineralisation geology/mineralogy and associated gold particle sizing can only be determined by sampling to facilitate optimised protocols. Mineralogical studies, focusing on particle size, particle clustering and distribution in host minerals, are required as part of wider paragenetic and metallurgical investigations. This paper discusses the role of mineralogical studies in the characterisation of gold ores for sampling optimisation through a series of case studies.

Jan 1, 2008

By W Pytel

A special model of vertically loaded pillar behaviour is introduced to the general, multi-plate based, floor-pillar-roof system interaction analogue. This permitted analysing room-and-pillar mine systems in any geological conditions, including the effect of pillar elastic-plastic behaviour with strain softening. In the model, pillar instability is one of the important phenomenon, which may be expected to occur, and which the operator has to be prepared for. Thus the entire systemÆs safety is determined mainly by strong roof strata behaviour and therefore they have to be examined in actual stress-strain conditions utilising the appropriate strength theories. It was assumed that the so-called safety margin, representing the relation between load intensity and material strength, might serve as the basic indicator of possible roof instability development. Therefore, the safety margin may be estimated by comparing the actually computed components of stress-strain tensor with ultimate values characteristic for a given material determined in laboratory. In order to illustrate the effect of technological pillar size on roof strata stability, two different mining systems (methods of mining) in one of the æPolkowice-SieroszowiceÆ Mine districts was modelled using the finite element method formulated in three dimensions, assuming different materials within different rock mass strata, as well as a number of horizontal planes of discontinuity within the model.

Jan 1, 2003

By J C. Macintosh

Capcoal Mine has modified its water use practices over the past 15 years. Two issues have changed the way water was managed:an economic review of water supply options for a planned expansion of the coal handling and preparation plant (CHPP) in the early 1990s, and increasing neighbour concerns about discharge of worked water from the mine into the local streams. These issues resulted in commitment by the site General Manager to cease discharge of worked water from site and to convert from using raw water to worked water in the CHPP. Operational needs, societal demands and continuing dry weather are again demanding change to the siteÆs water management strategy. This paper outlines the drivers for past and future operational change.

Jan 1, 2006

By Richmond AJ, Allan J

The use of long-hole in-seam drilling techniques for seam gas drainage ahead of mining was introduced to the Australian coal industry by ACIRL in mid-1981. ACIRL's research program has involved the development and demonstration of drilling and borehole survey technology in addition to evaluating the gas drainage potential of long-hole in- seam boreholes. This paper presents the results of the long-hole drilling carried out to date in the Illawarra District of the New South Wales coal fields. Drilling experience in relation to both vertical and horizontal directional control of the drill string, drill performance and borehole survey techniques are discussed. In addition, results of gas drainage effected by the long boreholes are presented. Future potential and requirements for further development of this technology are Reviewed.

Jan 1, 1982

By R Dimitrakopoulos, I Minniakhmetov

Geostatistical simulation techniques are used to quantify uncertainty of spatial attributes of interest describing mineral deposits, petroleum reservoirs, hydrogeological horizons, environmental contaminants and so on. The majority of existing methods consider second-order spatial statistics and Gaussian processes, while the more advanced multiple point-based simulation approaches are algorithmic and do not consistently account for the high-order spatial relations in data. Recently, simulation techniques for complex and non-Gaussian spatially distributed variables have been developed, based on high-order spatial cumulants, and make no assumptions on data distribution or require data transformations. In this paper, the previous developments are extended and a new approach for the joint simulation of multiple correlated variables using high-order spatial statistics is proposed. The technique is based on a new algorithm for the decorrelation of correlated variables into factors, using the so-termed diagonal domination condition of high-order cumulants. The decorrelated factors are then simulated using high-order simulation and back-transformed into the initial correlated variables. The decorrelation using diagonal domination of high-order statistics is tested with a data set from a multielement iron ore deposit, and then a fully known two-dimensional data set with two correlated variables is used to demonstrate the practical intricacies of the proposed method.CITATION:Minniakhmetov, I and Dimitrakopoulos, R, 2014. Joint simulation of correlated variables using high-order spatial statistics for orebody modelling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 53–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Meakins R. L, Talaska A, Kenny D, Haycraft J. A, Dickson B. L

A vehicle-mounted radiation detector interfaced to a microprocessor called PRAM (programmable radioactive analyser mobile) has been developed to provide grade control for selective mining of a soft rock uranium ore. The grade of ore over which the vehicle passes is determined and indicated by several coloured lights to a pegman who walks behind the vehicle. Coloured pegs are then laid out to mark the uranium grade ranges on the floor of the mine pit. Comparison between grade ranges determined by the PRAM and by prior drilling and downhole logging at the Yeelirrie deposit, Western Australia indicate good agreement. Use of the PRAM decreases the cost, manpower and time required to grade extensive areas of a mine pit floor.

Jan 1, 1982

By Chitombo GPF

The dilution of blasted ore with cemented backfill materials has been recognised as a significant factor influencing the economics of some underground metalliferous mining operations. Several mechanisms have heen identified as possible causes of fill failures. The purpose of this study was to determine the possibility of damage as the result of one mechanism, that of production blasting adjacent to bodies of cemented hydraulic fill (CHF). A vibration amplitude transfer function has been developed to model the transmission of blast vibrations from the source, through ore, across the ore to CHF interface and into the CHF mass. The model may be applied in the near field. The model has permitted estimation of vibration amplitude at a point in a CHF mass, to which damage criteria may be applied. A number of assumptions and simplifications have been made to render the problem relatively tractable. Ore and CHF material characteristics recorded by a number of authors were utilised to formulate preliminary damage estimations. A simple application of the amplitude transfer model indicated that a zone of plastically deformed CHF would be produced, and would extend to a distance of approximately 0.5 metres from the interface into the CHF. A sensitivity analysis was also conducted, that indicated that the zone of plastic deformation would be more extensive given appropriate conditions. Recommendations for further model development and future laboratory and field investigations have been made.

Jan 1, 1998

By S Januszewski and, G Dirom, D Christensen

Four field test plots were constructed in 1998 on a sloped waste rock surface at the Myra Falls Operations of Boliden Westmin (Canada) Limited to evaluate hydraulic performance of alternate cover system designs. The field test plot cover systems were designed to control oxygen ingress and water infiltration to the underlying waste rock while providing a medium for a grass and legume vegetation cover. The test plots consisted of a bare waste rock surface (control plot), and three additional plots consisting of native compacted till placed directly on the waste rock surface, overlain by non-compacted till. Two of the test plots included a compacted till layer ameliorated with flyash and bentonite, respectively, to improve moisture retention and reduce permeability. The third test plot consisted of a compacted layer of native till overlain by non-compacted till. A performance monitoring system was installed in each test plot to evaluate net percolation and oxygen ingress to the underlying waste rock. In addition, each test plot has profiles of matric suction, water content, and temperature sensors installed at up-slope and down slope locations. A review of four years of monitoring data shows that the compacted till/bentonite cover system has been most successful in limiting the infiltration of meteoric waters and oxygen ingress to the underlying waste rock material. The compacted till/flyash and compacted till cover systems have produced similar net percolation results and neither have functioned well in maintaining an oxygen ingress layer throughout the year. The amelioration of bentonite with till to produce a compacted barrier layer shows promise in reducing water and oxygen ingress at the MFO site, while the incorporation of flyash with the till did not result in a significant increase in performance. The field performance data clearly demonstrates the need for developing field trials prior to full-scale construction, as opposed to relying solely on an un-calibrated numerical modelling to design the full-scale cover system.

Jan 1, 2003

By T Higuchi, L Lu

The quality of iron ore fines have been deteriorating, which has affected sinter quality and productivity adversely. New pretreatment and sintering technologies are therefore required to tackle the gradual change in the quality of iron ore fines. In the sintering process, iron ore fines are first granulated with fluxes such as limestone and coke breeze, and are then loaded and fired in a sinter machine. Sinter productivity and quality are heavily influenced by the reactions occurring in the sintering bed. Hence fundamental understanding of these high temperature properties of ores is urgently needed.Formation of initial sinter melt, penetration and assimilation of nucleus particles by the initial melt, and consolidation and final solidification of final sinter melt are believed to be the key sintering reactions. The assimilation and penetration phenomena have been studied separately in the literature with model particles and diffusion couples and are therefore difficult to relate to sinter quality. In addition, the effect of ore mineralogy has not been studied in detail.In this study, tablets consisting of coarse particles from various iron ore fines as nucleus particles and chemical reagents as adhering fines were made and fired under various sintering conditions to investigate the penetration and assimilation behaviour simultaneously. The degree of assimilation, pore structure, compressive strength of the resultant analogue sinters were evaluated and the relationship between sinter strength and ore characteristics was further discussed. The nucleus particles from Ores A and B were found to be more porous and assimilated more readily with sinter melt, resulting in a viscous melt and a macro-porous sinter structure. The nucleus particles from Ores C and D on the other hand, assimilated less readily with sinter melt, resulting in a fluid melt and a denser sinter structure. This is consistent with the results reported in the literature, suggesting that the present evaluation method can be utilised for studying sintering reactions and predicting sinter quality.CITATION:Higuchi, T and Lu, L, 2017. Evaluation of sintering behaviour based on ore characteristics, in Proceedings Iron Ore 2017, pp 303–308 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Ellis WK, Greenwood-Smith R

A nuclear technique for the analysis of copper in bulk materials has been developed and successfully field tested at Mount Isa Mines Limited. The technique utilises the gamma-ray resonance scattering process. A bulk analyser based on this technique gives a rapid and accurate measurement of the percentage by weight of copper or nickel aver- aged over a large mass of sample, typically 20 kg. The only sample preparation required for accurate analysis is crushing to -2.5 cm. At Mount Isa over 100 mineral samples covering a wide range of rock types and copper contents were analysed. Bulk analyser assays and chemical laboratory assays agreed closely for underground pillar-extraction and geolog- ical chip samples, conveyor belt samples, and finely ground samples from the ore concentrator. For the concentrator samples, the root mean square deviation between bulk analyser and chem- ical laboratory assays was 0.06 wt.% copper. The chemical assay errors for these samples were about 0.06 wt.%

Jan 1, 1975

By R A. Pax

Heavy machinery such as AG and SAG mills generate a significant amount of noise due to the processes that are occurring inside them. From an environmental perspective, the level of noise generated is a significant occupational safety hazard. However from a technical perspective the noise presents an opportunity to determine some details of the processes occurring inside the mills. The noise generated is not random and can be attributed to a range of events that occur inside these mills, consequently non-contact acoustic determinations of in-mill behaviour provide powerful insights into the operation of the primary comminution tumbling mills. Traditionally, the use of perfect mixing has been assumed when modelling the operation of AG/SAG mills. If this were true then the acoustic emissions from AG/SAG mills would be uniform along the length of the mill. Experimentally this has been found not to be the case. From another perspective it should not be the case because of the different conditions existing at the feed end compared to the discharge end. This paper presents the results determined by non-contact acoustics and their analysis in terms of understanding of the mechanisms occurring inside a mill.

Aug 8, 2011

Structural geological modelling is a process which results in a 3D computer model that represents the essence of the geological and structural understanding of an area and is presented in a way that is directly useable, typically by internal customer groups. BHP Iron Ore operates a number of open cut iron ore mines in the Pilbara Region of Western Australia. The largest mine is the Mt Whaleback Mine located at Newman close to the southern margin of the Pilbara Craton. The structurally complex Mt Whaleback Mine is the largest metalliferous single pit open cut mine in Australia with over 1.6 billion tonnes of original iron ore resource. Additional to the Mt Whaleback Mine, a number of satellite open cut iron ore mines are operated by BHP Iron Ore (BHPIO) in the Newman area. BHPIO also operates the Yarrie mine approximately 400 km north of Newman at the northern edge of the Pilbara Craton Most of the BHPIO mines are located in the Archean- Proterozoic Hamersley Province that overlies the Archean granite-greenstone terrain of the Pilbara Craton. The orebodies are considered to be the result of supergene enrichment of the approximately 2.5 Ga Brockman Iron Formation and the slightly older Marra Mamba Iron Formation. Folding represents the most prevalent and penetrative structural element in the Newman area. Four folding phases have been identified regionally (Fj, F2, F3, F5), while a more local folding deformation (F4) developed mainly in the Mt Whaleback and Orebody 29 mine area. A northeast trending, southeast dipping, 45 km long, high angle, normal fault zone, the Whaleback Fault Zone, cuts through the Mt Whaleback mine resulting in an approximately 1400 in gap in stratigraphy. Additionally, two large, low angle, normal faults, the East Footwall Fault and the Central Fault, are present at the Mt Whaleback Mine. During the formation of supergene orebodies, up to 40 - 45 per cent volume loss occurred resulting in local non-tectonic deformation in the orebodies.

Jan 1, 1997

By P Hartlieb, M Noeger, M Varelija

Rock bolts are important in underground mining as they provide support to the rock mass around the excavation. They are the most common reinforcement method in mining and civil engineering excavations. The length of the bolts, types and spacing between them can be varied, depending on the reinforcement requirements and the use case (Kolapo, Onifade and Praise, 2022). The rock bolt provides safety and stability for the rock mass in the excavation area and they can be mechanically anchored, grouted, or friction anchored. They normally don’t have a measurement option and there is a possibility that it failed without showing visible signs on the surface, especially in grouted rebar bolts where they can still have some residual strength. Therefore, support functionality can be lost without recognising it. To overcome that, sensors can be installed on all three previously mentioned bolt systems. Intelligent bolts with implemented measuring systems have a function of showing changes and indicating if there is some damage on the bolt. So, it can be said that intelligent rock bolts are regular bolts equipped with additional instruments which are helping us detect potential instabilities inside of the rock mass or malfunction of the bolt itself. Changes in rock mass can be tracked, by measuring rock bolt reaction concerning the excavation response. Rock mass damage and instabilities are therefore measured in terms of rock mass deformation. Moreover, other additional information depending on the type of the sensor device could be collected. Based on such measurements, information about rock mass state can be derived. Different rock bolt types work at different reaction principles. Therefore, limitations on sensor application and information that can be extracted must be considered.

Sep 1, 2024

By M G. Aylmore

Thiosulphate is an attractive alternative reagent to cyanide for processing gold ores. It is relatively cheap and non-toxic, forms relatively strong gold and silver complexes, and readily leaches gold ores in ammoniacal solutions, catalysed by Cu(II). It is particularly suited to carbonaceous ores where the recovery of gold by cyanide is poor. However research over the past 20 years has identified a number of issues and impediments that must be understood or overcome before an overall process can be demonstrated as practical and economic for typical oxidised gold ores. This paper reviews our current understanding of thiosulphate chemistry and mechanism of gold dissolution, and discusses the stability of thiosulphate and polythionates. It then reviews the results of leaching various gold ores that have been reported in the literature, discusses gold recovery options, and considers environmental and toxicity issues. Some of the issues that require further research include decreasing the oxidation of thiosulphate by Cu(II) or other oxidants, increasing the extraction of gold compared to cyanide, and understanding the variation in gold recovery between ores. More work is also required to minimise the effect of polythionates on gold recovery using resins or alternative absorbents, to improve the elution of copper and gold from resins, and to recycle or minimise the concentration of reagents.

Jan 1, 2002

Innovative and Resource-Preserving Washing Processes for Primary and Secondary Raw Materials

Sep 13, 2010

The mostly submerged New Zealand sub-continent has a complex geological history and an active oceanographic regime that provides opportunities and challenges for offshore mineral exploration. Known deposits include polymetallic Fe-Mn nodules and crusts, polymetallic massive sulfides, phosphatic nodules, titanomagnetitie ironsands and placer gold deposits. Currently exploration interest is high with some 3.5 per cent of the EEZ under prospecting permit or application.   Article 76 of the UNCLOS convention allows coastal states to have sovereign rights over areas of the seafloor that are natural prolongations of the landmass that constitute submerged parts of the continental margin as extended continental shelf. New Zealand has substantial areas of elevated ridges and plateaux beyond the 200 M EEZ that form extended continental shelf. New Zealand has nearly completed a ten year, $44.4 M programme to define its outer extended continental shelf. New Zealand will lodge its outer limits of the extended continental shelf with the UN-appointed Commission on the Limits of the Continental Shelf in 2006, which if accepted, will enclose ~1.8 million km2 beyond the existing EEZ. Ocean Survey 20/20 is a follow-on marine mapping programme to underpin resource exploration and environmental management of the EEZ and extended continental shelf.

Jan 1, 2005