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By J Planner

As Australia’s coal and iron ore export volumes increase to meet international market growth, port terminals, mining operations and rail transport systems can be the source of increased dust emission. Current and future sustainable expansion must minimise dust emission from bulk handling and transport operations located in close proximity to residential areas. Lower level dust emissions can be controlled by operational measures such as water addition to products, and use of water spray on stockpile surfaces. Recent research has shown that higher levels of dust emission can be more effectively controlled by understanding and treating the dust characteristics of each individual bulk product. Application of this research, progressively being applied at Australia’s coal and iron ore port terminals and rail transport systems, is achieving compliance with health standards and minimising dust nuisance effects to an acceptable level.

Nov 22, 2011

By J Paradis, K Dudgeon, M Topping

At Newmont’s Jundee Operation, exploration and resource geologists collaborated to produce an open pit resource model. Using a variety of modelling and estimation techniques but no new data, an uneconomic underground target was converted into a potentially economic open pit evaluation. During an industry downturn, it is more important than ever to efficiently share expertise, ideas and resources to problem solve and produce meaningful project outcomes. The two departments brought together different methods and ideas, and the process showed that certain methods worked better than others in different situations, thus the appropriate method was applied to each part of the evaluation. The results were used to create new procedures and improved lithology modelling and resource model estimations. Adaptability of the geology departments and collaboration such as this are key to ongoing improvements and future mine life at Jundee.CITATION:Dudgeon, K, Paradis, J and Topping, M, 2014. Cook open pit model – the hurdles: how we leapt, lunged, stumbled and overcame them, in Proceedings Ninth International Mining Geology Conference 2014 , pp 169–174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

The mechanisms of fragmentation in homogeneous materials and structured rock mass are reviewed. A method previously used to predict vibration damage to the remaining rock is extended and shown to be valid for the prediction of fragmentation in the rock mass removed by blasting. The effectiveness of different explosives in different types of rock blasting is discussed.

Jan 1, 1990

In a country richly endowed in mineral wealth, Climax Arintco Mining Corporation's ICAMC) Dinkidi porphyry Au-Cu deposit in Nueva Vizcaya, Philippines, represents the most significant mineral discovery in this country in recent times. The deposit is located within a belt of young intrusive and volcanic rocks in the Sierra Madre mountain chain of north Luzon, a region previously unassociated with porphyry -style mineralisation.Since 1989, drilling of the Dinkidi deposit has outlined a resource of 124 million tonnes of 1.0 g/t gold and 0.4 per cent copper. Regional exploration throughout CAMC's 37 000 hectare FTAA has identified a further 16 potential porphyry-related deposits.

Jan 1, 1997

By S Thomas, S Ricketts, R Hassell

Northern Star Resources (NSR) operates several operations utilising narrow vein stoping operations in the Kundana area. Stope dilution performance is variable across these operations, with unplanned dilution reducing individual stope economic viability, increasing risk to personnel and machinery operating in and around the stope and delaying the overall stoping sequence. Technical investigations were undertaken to objectively understand the variables which had the largest impact on stope performance and then use the findings to help develop mining strategies to reduce dilution. A stope reconciliation process was developed to compile key stope performance information such as stope design parameters, geotechnical and drill and blast factors. These were compared against the measured dilution. Production targets necessitated a high turnover of stopes in the operations, and hence a requirement for an expeditious process and mine design software with automated tools. The output of these results, together with numerical variables from geological, geotechnical and drill and blast data were analysed via multivariate regression. The analysis identified the factors with the greatest influence over stope dilution, and a forecast model was consequently created. Confidence was gained in the model when the subsequent stopes performed in line with prediction. Different drill and blast designs were subsequently trialled and found to reduce dilution. The model was then updated with the new practices, facilitating further regression analysis to identify revised key controlling factors. The subsequent production results however, displayed a poor correlation with the prediction from the revised model. Inconsistencies in drill and blast designs and execution were identified as key factors in the dilution performance. This was an important finding as the correct implementation of the design is critical and this has become a key focus for future stoping. Overall the technique presents an objective process to identify causal factors of stope dilution resulting in improved economic metrics for stope production. The process will be applied to other similar Northern Star operations.

Mar 15, 2021

By G Swayn, J Harpley

Spent Pot Lining (SPL) is an unavoidable waste product of the electrolytic process in the smelting of aluminium. SPL is considered to be a hazardous waste in various countries because it contains significant quantities of absorbed fluoride along with traces of cyanide. The disposal of SPL has been primarily in landfill because of difficulties in the development of a successful techno-economic SPL treatment process. Increasing concern about SPL landfilling practices is resulting in regulations in some countries to ban this form of disposal. As a consequence stock piling of SPL is occurring in an increasing number of countries pending the development of a successful treatment process. In 1992 Portland Aluminium investigated a SPL treatment process based on pyrometallurgical technology and approached a company called Ausmelt in Dandenong, Victoria, Australia, to ascertain if their submerged lance technology furnace process would be suitable to treat SPL. This approach resulted in Portland Aluminium, Alcoa and Ausmelt personnel working together on trials during 1992 - 1994 in Ausmelt's demonstration furnace to produce a slag and off gases containing hydrogen and sodium fluoride. The trials also evaluated the effect of oxygen enrichment to increase the concentration of hydrogen fluoride and the ability to recycle sodium fluoride particulate produced as the furnace off gases cooled. Other separate developmental work by Portland Aluminium, using CSIRO, resulted in the production of aluminium fluoride from the offgases from the pyrometallurgical process. The results of these projects influenced Portland Aluminium and Alcoa to authorise up to $A26 400 000 in December 1995 to construct a Research and Development processing facility to treat SPL at Portland. The Portland Aluminium unique gas treatment process converts hydrogen fluoride in the furnace offgases to aluminium fluoride in a multistage fluidised bed reactor, designed by Portland Aluminium. The aluminium fluoride produced in the reactor has been trialed successfully in Alcoa's aluminium smelting process as a replacement for imported aluminium fluoride. The installation in mid-2001 of a slag granulation system has enabled the production of a granulated vitreous slag having leachability qualities that conform to Victorian EPA criteria for the unrestricted use of the granulated vitreous slag from 'The Alcoa Portland SPL Process'. The unrestricted use of the granulated slag successfully completes 'The Alcoa Portland SPL Process' which treats the hazardous waste material SPL and converts it into non hazardous useful products.

Jan 1, 2002

By Green S, McKernan, Skrypniuk

In November 1996, Boddington Gold Mine (BGM) began the implementation of an expert system. The objective of the expert system was to improve plant efficiency by developing an `operator best practice' control philosophy for the grinding circuit

Jan 1, 1997

By Das S. C

A detailed study was undertaken on the effect of Fe+3 in combination with LIX64N during copper electrowinning from sulphate electrolytes. The results show that the presence of Fe+3 not only affects the current efficiency during copper electrowinning but also affects the cathode quality. The effect is enhanced by electrolysis parameters like temperature, circulation rate, current density, etc. No significant effect was found from the presence of Fe+2. The presence of Fe+3 along with LIX64N causes a synergistic effect and results in a drastic fall in current efficiency. Moreover, cathode quality is also affected. A pyramidal structure is favoured in the presence of Fe+3 but the presence of LIX64N along with Fe+3 promotes a ridge structure. Addition of thiourea not only causes modification of cathode deposits, but also a rise in current Efficiency.

Jan 1, 1992

THE filter-press, which has done so much for the successful-treatment of the sulpho-telluride ores of Kalgoorlie, has a serious rival in the vacuum process, and this paper is written with a view to arousing more interest in the cheaper working of the press, it being doubtful whether its efficiency in extraction can be improved upon. Before proceeding with the actual working of the press, it may be as well to make brief mention of the character of the ore treated at the Associated Northern Blocks, where these notes were compiled. A sample from several weeks' run was taken of the raw ore, with the following analysis...

Jan 1, 1911

Cable bolts are being used more extensively by the mining industry for many different rock reinforcement applications. The configuration of these bolts has evolved over the last 20 years to meet the immediate needs of industry at the particular time. Most improvements to date have focussed on increasing the mechanical performance with little attention given to issues such as ease of handling, matching response to that of the rock mass or corrosion protection. Ultrastrand has been designed and being developed with this broad perspective in mind so that it will satisfy the ground reinforcement needs of today's and tomorrow's mining industry.Laboratory tests on Ultrastrand prototypes have confirmed that mechanical performance is superior or equivalent to Standard and Birdcage Strand respectively. Preliminary discussions have been held with an installation equipment manufacturer with a view to conducting a trial at a mine site by early-1992.

Jan 1, 1992

By J Pan, T Chun, D Zhu, Z Guo, J M. Young, T C. Ooi

With the rapid development of the Chinese steel industry, the strong demand for iron ores has led to huge imports of various iron ores from all over the world. As a relatively new force in the iron ore world and an important raw material supplier, Fortescue Metals Group (FMG) has achieved an annualised production rate of 100 Mt of iron ore fines. Typical blends were designed to simulate sinter blends employed in Chinese steel mills, and to determine sintering properties and metallurgical performance of blends comprising FMG Rocket fines in pilot sinter pot. It is shown that the sinter of typical blends comprising 15 - 20 per cent rocket fines possesses excellent sintering properties and metallurgical performance. With Rocket fines substitution for competitor ores in a typical customer mill blend comprising fully imported fines, the sinter productivity and tumble index increased from 1.45 t/m2h and 62.0 per cent to 1.54 t/m2h and 64.0 per cent, respectively, while attaining similar reducibility index and reduction degradation index at lower solid fuel consumption.CITATION:Zhu, D, Guo, Z, Ooi, T C, Chun, T, Pan, J and Young, J M, 2013. Sintering and metallurgical performance of blends comprising Fortescue Metals Group rocket fines, in Proceedings Iron Ore 2013 , pp 519-524 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Buoyant levels of world economic growth and recovery in intensity of metals usage suggest that demand for minerals will remain relatively strong into the 1990's. Supply constraints, low stock to use ratios, financial and political factors imply lower elasticities of supply for minerals in the future. The outlook for minerals and metals prices from a pro-ducers viewpoint is, accordingly, promising.The recent recovery in world minerals prices, following strong growth in the world economy over the last few years, makes it appropriate to consider the structural forces at work in the formation of world demand and supply of minerals. This paper will review past trends and consider some of the main economic issues facing the mining industry in the 1990's.

Jan 1, 1990

In the five years since Great Central Mines Limited (GCM) commenced exploration in the Jundee and Bronzewing areas of Western Australia's Yandal greenstone belt, the Company has been transformed from a junior explorer into Australia's fourth largest gold producer with annual production of approximately 440 000 ounces and mineral resources of seven million ounces of gold.The growth in resources has been driven by a high quality geoscientific approach, supported by a substantial budget for drilling and strong management commitment. In 1997, the Company expects to spend US$30 million on exploration in the Yandal greenstone belt.

Jan 1, 1997

The basic methods to remove material from underground mines are to: convey continuously, batch in trucks, or batch in a shaft hoisting system. A critical aspect in shaft hoisting is accurately batch loading the conveyance or skip. During the 20th century, the almost universally accepted method of loading was via a measuring flask. A measured quantity of material was filled into the flask as the conveyance traveled through the shaft and then, when the conveyance arrived at the loading position, it was ædumpedÆ into the skip for hoisting. Two skip loading conveyor systems have been developed in Australia: BHP BillitonÆs Cannington Hoisting System, installed in 1996, is believed to be the first conveyor loading system designed for two skips. Two parallel conveyors were installed with a two-way gate controlling feed onto each belt. Cannington was ideally suited to conveyor loading as the very high ore density and relatively low production rate required a relatively small volumetric storage capacity on the weighed belt. Newcrest MiningÆs Telfer Hoisting System, which is to be commissioned in 2005, consists of a single slewing conveyor loading each skip with 32 tonnes of ore. The development of this system eliminates the two-way transfer, improves the accessibility and minimises the excavation required. While every hoisting system must be considered on its merits, conveyor loading offers significant advantages to the Mining Industry in the 21st century.

Jan 1, 2005

Carbonate-hosted massive sulfide ores of the American cordillera compose a distinctive genetic class. Discordant fea-tures of occurrence together with measured high-temperatures of formation indicate their essential epigenetic character and close spatial association with centers of thermal activity during evolution of the cordillera. Their metallogenic character is complex from region to region: Cu-Zn-Pb-Ag, Pb-Zn-Ag, and Cu-Zn-Ag-Au represent extremes of composition and each may be identified with specific terranes of occurrence, notwithstand-ing an inferred common process of formation. Beyond the presence of a thermal center, other controls that may be identi-fied include apparent but obscure properties of primary perme-ability or chemistry of hosting strata, and secondary controls are imposed by stratigraphic differences in which permeability is strongly contrasted. Structures that act as channelways may be identified in some instances. Notwithstanding their intrinsic value, search for these ores is difficult and requires the solution of complex geochemical and three-dimensional geometric problems.

Jan 1, 1990

With the recent increase in the number of underground secondary sulphide dust explosions in Canada, Australia and elsewhere in massive sulphide ore mining industry, establishment of quantitative and realistic methods of analyzing the mine dust is of paramount importance. This paper examines and analyses dust samples from a mine area that has very recently experienced sulphide dust explosions. Also, it attempts to evaluate the physical and chemical characteristics of the dust. Explosibility of the dust samples was determined by quantifying the oxidation reaction of the sulphide dust particles in a 1.2 L, Lindenberg open horizontal tube furnace. Percentage sulphur', % S oxidised during ignition of a dust sample of known assay, % S and dust concentration (g/m3) were determined by the quantitative chemical analysis of SO2 gas produced during the oxidation reaction. A dust sample with high sulphur content, 22.3% S (assayed) and mean particle size 9.82 pm, was found to exhibit a low degree of oxidation compared with a sample of low sulphur content, 15.44% S and mean particle size 21.7 tcm, at the same Temperature.

Jan 1, 1988

By A Mirzaghorbnali, D Gilbert, R Burton, J Nemcik, N Aziz

Glass-reinforced polymer bolts, commonly known as fibreglass dowels and fibre-reinforced polymer or plastic bolts or plastic dowels are increasingly applied for strata reinforcement in mines as well as in concrete reinforcement in civil engineering. The most popular dowels used in coalmines are the 22?mm diameter fully threaded type. Fibreglass and plastic bolts are cuttable, easy to handle, lightweight and corrosive resistant. A series of tests were undertaken to evaluate various strength properties of fibreglass dowels. These included tensile failure tests by the double-embedment method, a single guillotine shear test and a double shear test, carried out on dowels installed in concrete blocks, and with punch shear tests. Punch shear tests were used to evaluate the dowel shear strength parallel and perpendicular to the fibreglass strands or elements direction of extrusion. The study found that the tensile strength of the 22?mm diameter fibreglass dowels was in the order of 30?t. In the shear testing, the peak shear load was influenced by the encapsulation grout type and the level of fibreglass axial pretension. Also, there was a nearly fivefold difference in the shear strength value of fibreglass dowels tested parallel as against perpendicular to the dowel axis.CITATION:Aziz, N, Gilbert, D, Nemcik, J, Mirzaghorbnali, A and Burton, R, 2014. The strength properties of fibreglass and other polymer-based dowels for strata reinforcement in coalmines, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 263–268 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

The Cadjebut Mine is located 80 km southeast of Fitzroy Crossing. Cadjebut is owned 58 per cent by BHP Minerals and 42 per cent by Billiton Australia. Cadjebut is a 'Mississippi Valley Type' (MVT) deposit. Minerals present are sphalerite, galena and marcasite in a sedimentary host of dolomite and siltstone. The ore contains few deleterious impurities and no silver. The mill was commissioned in the first half of 1988 at a rate of 320 000 tonnes per annum. An expansion in the latter half of 1989 has since increased production to 550 000 tonnes per annum. The initial geological resource at the commencement of mining was 3.8 million tonnes at 13.5 per cent Zn and 4.4 per cent Pb. There is sufficient ore left to sustain operations to 1995 at a grade of 11.2 per cent Zn and 3.9 per cent Pb. The ore from underground is stockpiled on the surface via a drift conveyor and from the stockpile is fed into a grinding circuit consisting of a SAG and ball mill. Cyclone overflow at a Pgp of 90 pm gravitates to the flotation circuit. Lead and zinc are sequentially floated to produce an 80 per cent Pb grade at 90 per cent recovery and a 61 - 62 per cent Zn grade at 96 per cent recovery. The concentrates are thickened and filtered before being trucked to the port of Wyndham 600 km away. From Wyndham the concentrates are shipped to smelters in Asia, Europe and Australia.

Jan 1, 1992

By D Martin

The Rio Tinto (Mount Bruce Mining Pty Ltd) Koodaideri Iron Ore Project is located approximately 110 km north-west of Newman in the Pilbara region of Western Australia. During detailed ecological studies of the project area, a significant maternity roost (containing around 430 individuals) of the Orange Leaf-nosed Bat (OLNB) (Rhinonicteris aurantius) was discovered within the boundaries of the proposed mining area. The OLNB is listed as Vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 and is listed as a Schedule 1 species under the Western Australian Wildlife Conservation Act 1950.With a good understanding of blast vibration attenuation in the Pilbara’s different geologies and in the absence of other known studies, it was considered that appropriate buffer distances between mining and bat colonies were not scientifically determined. Therefore, to inform the environmental approvals process that was underway, a series of seismic blasts was planned to assess and measure the sensitivity of the OLNB to trial-sized seismic blasting activities to develop a more scientifically based buffer zone for the protection of the OLNB. This was to be achieved by testing ground attenuation of the site and measuring any response from the OLNB to the firing of seismic charges. Rio Tinto sought the independent expertise of ecological consultants to evaluate and participate in the work to quantify the level of sensitivity of the bat colony and to outline the proposal to government authorities.After detailed risk assessment and project mapping, the seismic blasts were implemented, with the aim of firing individual charged and measured vector peak particle velocity (VPPV) at the OLNB roost cave, combined with monitoring OLNB disturbance activity within the roost that was invoked by the blasts. A series of six charges were fired with the VPPV ranging from 0.66 mms-1 to 18.70 mms-1. The OLNB activity was monitored using high frequency microphones, which detect bat calls emitted during flight. Under daytime conditions, the bats would normally be dormant, so the null hypothesis was for no calls to be detected if the bats displayed no disturbance behaviour. This work has improved understanding of mining activities (blasting) on the OLNB species, assisting in establishing mining exclusion zones that are based on scientific data, contributing to a sustainable future for both the environment and the mining industry.CITATION:Martin, D, 2015. Scientific evaluation of fauna sensitivity to blasting, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 519–526 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Yamada K, Abe H

Magnetic scanning type mass spectrometers have been given improved sensitivity with a large dynamic range and considerable resolution by the addition of a computer-controlled electric equipment. A mass spectrometer equipped with this newly developed electric system was applied to studies of the activities of liquid iron-silicon alloys and of liquid iron-phosphorus alloys at 1600¦C. The range of silicon concentration was 5.8at%-51.1 Si= at%, and values of ySi -3.1+0.15 and es 11.5 +1.5 were obtained. The concentration range of phosphorus was 1.3at%-5.7at% and a value of eP=7.3+0.1 was obtained.

Jan 1, 1980