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Explosives have been an important tool for unlocking minearl wealth from the earth's crust for several countries. In'the past, innovation in explosives technology, spurred on by industry needs has assisted the Mining Industry to improve productivity and reduce costs. A symbolic relationship exists between Explosives and Mining. Australia has vast mineral wealth. Our Mining Industry is of major importance to the Economy., The value of mineral produc- tion in 1987 was $25 million or 10% of GDP. Australian Mining is a business depending on international markets. The Mining Industry is our leading export earner, generating 44% of all export income. 60% of mineral production is exported. About half of these minerals are extracted using explosives. Explosives rank as one of the top three consumable expenditures for a mine. For example: A major open-cut iron or coal mine can spend $6 million dollar per annum on explosives.

Jan 1, 1988

By T Harding, T Riggs, D Taylor

High-grade hematite ores in the Hamersley Province of Western Australia are associated with hydrothermal magnetite-apatite and magnetite-hematite-carbonate-apatite proto ores below the modern weathering surface. In addition, hydrothermal alteration of country rocks, once believed to be absent, is now recognised widely in shales and dolerites up to several hundreds of metres away from the ores. Both observations appear to exclude a simple supergene model for ugrading the host iron formations to high-grade hematite ore. Similar hydrothermal proto ores and country rock alteration are now being recognised in other high-grade hematite deposits worldwide, or have been recognised in the past.

Jan 1, 2002

By M Swart, H Ståhlbröst, P Toor

Development of SAG liners has always been a strong focus and interest in mineral processing as SAG liners significantly impact on plant performance (throughput and grind size), material costs and plant downtime. SAG shell relines typically determine the frequency and duration of plant shutdowns. Early SAG shell liner designs relied heavily on practical experiences and were limited in their size due to weight restrictions. Significant developments in Discrete Element Method (DEM) modelling, material and manufacturing technologies and larger reline machines have resulted in new and improved liner designs. This paper discusses the evolution of SAG shell liner design and its progression to the Skip Row design. Case studies have been provided for the Skip Row design in a variety of applications such as Single Stage SAG (SSS), SAG and Ball (SAB), SAG and Ball with Crushing (SABC) and Pre-Crush at a variety of mill diameters ranging from 24 foot to 34 foot. A detailed assessment has also been carried out comparing liner service life, ease of reline and performance (throughput, power and grind size) for a large 34 foot SAG mill when compared to the previous design.CITATION:Toor, P, Swart, M and Ståhlbröst, H, 2017. The evolution of SAG shell lining and introduction of the skip row design, in Proceedings MetPlant 2017, pp 158–184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By L O. Filippov, A Piçarra, I V. Filippova, N P. Lima, K Silva

The reverse cationic flotation using the starch as depressor of iron oxides is the most efficient upgrading process when is applied to the simple systems composed by hematite/magnetite and quartz. The fundamental studies performed with iron ore samples from different deposits over the world (Brazil, Russia, Mexico) confirmed the inefficiency of starch when the silica content in the concentrate is controlled by Fe/Mg-bearing minerals. The main approaches for solving these issues focused on using new collector formulations or new depressants. However, the alternative depressants tested inhibited flotation of quartz or were less efficient as iron oxide depressant. In this work, a comparison between new amidoamine collector with conventionally used etheramine and oleate collectors in the flotation of pure minerals and actual iron ore samples was performed. The electrophoretic mobility, contact angle and infrared spectroscopy measurements allowed to deduce the hindrance effect as main mechanism of selective adsorption of the amidoamine on the quartz surface compared to hematite and kaolinite. Molecular modelling studies revealed that this steric hindrance effect can be explained by the combination of the "shield" formed by the coordinating water molecules on the (001)-D2 hematite surface and the large volume of the amidoamine head group. The amidoamine tested as collector without use of a depressant showed excellent flotation selectivity allowing the total flotation of quartz from a mixture with hematite. High collector performance and selectivity were confirmed during reverse flotation of quartz using continuous flotation column (D = 500 mm; H = 4000 mm) and allowed to produce the iron concentrates with more than 60 per cent of iron from the rejected slimes samples of Vargem Grande 2 processing plant (Iron Quadrangle, MG, Brazil). The new collector allowed to develop flexible flotation flow sheets to process the iron ore with a complex gangue mineralogy and unlock the old altered tailings and slimes product as new resources

Aug 24, 2022

This paper presents a resume of the likely profitable mining areas in New Zealand. It covers the main 'minerals' û gold, coal, oil and gas, ironsands, silica sands, clays, lump silica, perlite, sulphur and limestone. The potential mining projects are depicted on a map of New Zealand together with the associated works involved in hydro-electric and geothermal power development requirement for industries such as aluminium, nickel ferro-silicon or silicon carbide production. The political need for mining development to relieve unemployment and reverse emigration is stressed. A case is made for exploration and development assistance by government in labour re-training, energy supply and transportation, if the tremendous losses through lack of use of human and industrial resources are to be rapidly reduced. These losses are currently estimated at $10 000 000 000 per year. The need for protection of the sanctity of contract and security of tenure of all mining operations is touched on briefly as is the need for a reasonably balanced view on conservation. However, as both of these are more properly covered in papers on the legal and environmental aspects of the mining climate, they are presented here only as they affect the economy of the mining operation. Finally, there is a brief comment on the mining climate in New Zealand relative to Australia and South Pacific mining operations.

Jan 1, 1990

Amongst the unavoidable studies of the mining engineer who desires to reach the maximum efficiency, is the subject of patents. With the fundamental principles of the patent laws of this and other leading countries he should of course befamiliar, but still more should he keep abreast of that practical knowledge which will enable him to act or advise wisely when the patenting of a new invention, or the sale, purchasing, or adoption of a new patented machine or process becomes amatter for consideration. As every engineer worthy of the name is an inventor and more particularly every mining engineer he has a direct interest in watching the progress of legislation and administration concerning patent monopolies.His worldly prospects may indeed, to a considerable extent, depend upon the defeat of bad patent laws and the removal of incompetent officials, or the appointment of better ones. Better patent administration is always in Australia a valid requirement, and until engineers generally take up and press the demand, bad administration is likely to continue. Even though every engineer is not a patentee, nevertheless his interests in patents must always be direct and powerful, and ignorance or apathy in regard thereto must inevitably injure either his own interests or those of his employer. When we consider the tens of thousands of mines scattered through Australia alone, on everyone of which there is expensivepatented machinery, and when we consider the thousands of...

Jan 1, 1901

Three methods of gold analysis are briefly described highlighting some of the problems and advantages of each. The variation of results between samples and splits and due to method of preparation is illustrated. The mean per cent difference of the fire assay values from the means of sample split values for three cases is 15 per cent.Finally, a comparison of the aqua regia leach atomic absorption spectroscopy (AAS) and fire assay fusion AAS techniques is made.This shows that the mean precision, the ability to obtain the same value, of the methods at 98 per cent confidence is ± 30 per cent and ± 15 per cent respectively. The fire assay fusion AAS method is relatively more accurate than the aqua regia one.

Jan 1, 1984

By B Belle

Dust sampling is pivotal in estimating the ‘dose’ of dust exposure and in deriving dose-response curves in epidemiological studies. Over the last half century, gravimetric sampling has been the fundamental means for dust exposure monitoring using recognised respirable size-selective standards. In Australia, a gravimetric sampling technique has been followed since 1983 using the Higgins-Dewell (HD) type cyclones (AS2985). The re-emergence of ‘Black Lung’ or Coal Workers Pneumoconiosis (CWP) in Queensland, Australia has re-kindled the need for better understanding of personal dust monitoring, compliance determination, accuracy, timeliness of sampling results and dust control systems. Reporting dust levels in real time empowers miners and operators to take immediate action to avoid being exposed to excessive airborne dust. Two decades of intensive research in the USA has led to the introduction of gravimetric based continuous personal dust monitors (CPDMs) called PDM3700 as compliance tools. The new real-time mass based sensor is a continuous mass based dust monitor using the Tapered Element Oscillating Microbalance (TEOM) principle and is regarded as significantly superior to the current gravimetric sampling methodology.Recently the overall respirable dust standard in USA coalmines has been reduced from the historic 2.0 to 1.5 mg/m3. This paper provides the results of a comparative pairwise study of an existing gravimetric sampler and the PDM3700 carried out in 3 different Australian underground mines. The field results consistently suggest that there is a significant ‘measurement bias’ between the current gravimetric HD sampler and the PDM3700 monitor operated using a similar HD type cyclone. The results show that the currently used cyclone measurements are approximately 59 per cent higher than the ‘auditable’ PDM3700 monitor data at the current compliance limit of 3 mg/m3. Based on a review of the extensive data collected, the differences can in part be attributed to the aerosol size selectivity of the samplers with the current gravimetric sampler used in mines, collecting more larger sized particles (D90 of 15 µm). This finding has significant consequences for historic exposure results and their use in medical surveillance programs, as well as the current approach to non-compliance determination.CITATION:Belle, B, 2017. Pairwise evaluation of PDM3700 and traditional gravimetric sampler for personal dust exposure assessment, in Proceedings Australian Mine Vent Conference 2017, pp 87–92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

The excavatability of the rock mass in a proposed open pit mine at Globe-Progress has been assessed. The rock mass was initially evaluated by determining variations in seismic velocity and by using the Revised Size-Strength Chart. These two assessments should be performed during the feasibility or early investigation stages of a project. A complete rock mass excavatability assessment using a suite of geological and geotechnical properties was then performed using three methods: RMR System; Modified Rippability Rating; and a productivity estimation method. These three methods should be applied during the investigation and design stages of a project. The preliminary assessments show that most of the open pit rock mass is expected to be rippable. The complete assessment differentiates weak, fair and good rock masses within the open pit. Weak rock mass exists along the Globe-Progress Shear zone, located along the northern and eastern pit walls and also in the western pit wall where the Chemist Shop Fault is located are both regions are expected to be diggable. Relatively weak rock mass also exists along the Globe-Progress Shear axial hinge. The Globe-Progress Shear limbs are generally fair to good rock where moderate to hard ripping should be expected.

Jan 1, 1996

The modern Golden Cross mine entered the production phase in January 1992. The project is designed to produce over 100 000 oz/yr of gold and over 300 000 oz/yr of silver during a mine life of eight years. An open pit and an underground mine are operated producing around 850 000 t/yr of ore, to feed a conventional carbon-in-leach processing plant. Golden Cross is owned in joint venture by Coeur Gold New Zealand Limited (80%) and Viking Mining Company Limited (20 %).   Since the start of production several major aspects of the design have altered. The underground mine began as a mechanised cut and fill operation. The cut and fill stoping progresses in 3.3 m flatback lifts with maximum stoping width of 6 m. Where the ore zone is wider than 6 m a post pillar cut and fill method is used. In 1993 a new bench mining plan was introduced between the 270 and 260 levels. Flatbacking continued in the footwall drives in anticipation of variability of the ore width and orientation. The development of levels below the main service 200 level has indicated a possibility of bulk mining the ore block rather than flatbacks. This could lower mining costs but also introduce higher dilution rates. Development is in the advanced stages for trialing this method.

Jan 1, 1994

The dynamic response of holdup in a continuous ball mill has a direct influence on the rate function of grinding kinetics and is useful for predicting the variation in the size distribution of the finished product with time.A model was proposed involving three interacting, completely mixed chambers and this was used to derive analytically the transfer function of the system, from which the unit impulse response and the unit step response of the holdup with feed rate were obtained.The theory was confirmed by comparing it with previously published experimental data for the residence time distribution of particles passing through a ball mill.

Jan 1, 1975

The Effect of Bulk Iron Concentration on the Copper Activation of Sphalerite at pH 9

Sep 13, 2010

Improving the Sustainability of Primary Metal Production - The Need for a Life Cycle Approach

Sep 13, 2010

This paper describes the new legislative regime that will apply to the regulation of the minerals industry in New Zealand. The reform of New ZealandÆs minerals legislation was initiated in January 1988 when the Minister for the Environment, Rt Hon Geoffrey Palmer, announced the Governments intention to review all the major laws governing New ZealandÆs resources. The Resource Management Bill is scheduled for introduction to the House in December 1989 and its date of enactment is scheduled for June 1990. With some matters still to be determined (at the time of writing), this paper cannot be a definitive review and description of the new legislation, it is instead an attempt to outline the major features of the Bill, to date, that are seen as important to the mining industry.

Jan 1, 1990

By J R. Manuel, J M. F Clout

The importance of goethite to Australian iron ore production is steadily increasing as the proportion of goethite-rich, martite-goethite bedded and channel iron deposits increases at the expense of declining production from high-grade microplaty hematite deposits. For this reason, an improved understanding of goethite in iron deposits, its genesis, goethite types and their physical and metallurgical properties is vital to maintaining optimum sintering and blast furnace performance in Asian steel mills.The terminology used to describe goethite in Australian iron deposits is currently highly variable. The discredited mineral name ‘limonite’ is still in widespread use as a field term for goethite and there are many misconceptions concerning goethite chemical grade and downstream physical and metallurgical properties. The goethite classification proposed here is based on geological and physical properties from which three types are recognised including brown goethite, dark brown-black vitreous goethite and highly microporous, friable yellow ochreous goethite.In practice, typical vitreous goethite with highly reflective surfaces and conchoidal fracturing, characteristic of the hard cap zone appears from X-ray fluorescence (XRF) and electron microprobe analysis to be significantly higher in Si (up to 18.7 wt per cent), Al (up to 3.5 wt per cent) and S (up to 0.14 wt per cent) compared to the generally very low (<1 wt per cent for Si and Al) levels of these elements in ochreous goethite and brown goethite. The data dispels the common misconception that friable earthy or yellow ochreous goethite is high in Al and Si and other chemical impurities. However, P was found to be consistently higher (mean of 0.112 wt per cent and up to 0.296 wt per cent) in ochreous goethite than brown goethite (mean of 0.011 wt per cent) or vitreous goethite (mean of 0.031 wt per cent). The highly porous microstructure of ochreous goethite is thought to have a much higher surface area, which may aid in preferential adsorption of P onto the ochreous goethite mineral surface.CITATION:Manuel, J R and Clout, J M F, 2017. Goethite classification, distribution and properties with reference to Australian iron deposits, in Proceedings Iron Ore 2017, pp 567–574 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By B E. Hall, J Poniewierski, A J. Hills

Following a review of life-of-asset work at MMG’s Rosebery mine in which a proposal to increase production from 0.8 Mt/a to 1.2 Mt/a was mooted, questions were raised as to the seemingly arbitrary reasoning for the production increase. They included: Did the proposal actually add value? Was the production rate from the mine sustainable? Was it the best identifiable value-adding configuration?A multiple scenario analysis study commenced to model how various cut-off grade values against mill throughput, along with associated capital expenditure, would impact on the potential value of the operation. This was carried out utilising the ‘hill of value’ approach promoted by AMC Consultants.The traditional approach to these studies uses a constant cut-off value (NSR – net smelter return) for the whole mine analysis. This was thought to potentially introduce a large amount of variability to the model as different ore types were thought to have different processing costs and different underground lenses were thought to have different mining costs. With the aim of developing a consistent value measure that would be comparable between the lenses, an alternative measure was suggested for all ore block values in this model, irrespective of lens location.The new measure used was a mine variable value (MVV). This allowed for the variable factors of final metal concentrate production to be removed from the ore value. From a mining point this was the haulage distance from ore source to run-of-mine (ROM). For the mill it was the amount of reagents required, varying based on grade together with the amount of power required for crushing, grinding and tailings handling.From the initial run of the model, preliminary results lead to a conclusion of increased value being gained by either increasing cut-off grade or increased mill throughput rate. The validity of the result was tested using alternative price scenarios, which although changed the absolute value achieved did not significantly change the identified value-adding strategies. The realisation of these value increases identified are however contingent on higher sustainable development rates being able to be achieved mine-wide, higher backfilling rates being able to be achieved and overcoming recognised ventilation constraints. Further detailed studies are being put in place to identify the practicality of overcoming these recognised constraints and achieving the higher-value strategies identified.The ongoing objective of the hill of value model built is to keep the model alive as a life-of-asset planning tool and to continue refining the foundation data, such that various mining strategies can be analysed with increased confidence.CITATION:Hills, A J, Hall, B E and Poniewierski, J, 2014. Mining scenario analysis and mine variable value, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 111–118 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By Bodnaras G. E, Sceresini P. A

The Filblast Cyanidation Process incorporates the advantages of intense high shear mixing, high dissolved oxygen concentration and high pressure to achieve extremely rapid gold dissolution rates. This is made possible by the unique design of the Filblast gas shear reactor. The reactor is a rugged and compact in-line device. The outer casing is protected by a polyurethane coating and the internal parts are of wear resistant polymer. The largest unit built to-date has overall dimensions of 1200 mm length by 300 mm diameter and has a capacity of 150 dry tonnes per hour at 40 - 45 per cent solids. Service life at this throughput is at least three months. The process may further be applied to high temperature leaching of refractory gold ores or other metals. Wear resistant metal or ceramic materials would be employed for this duty. Four mines are currently employing the Filblast Process for treating a variety of ore types ranging from highly reactive, almost impossible to treat, pyrrhotite/arsenopyrite to deeply weathered clay ore which forms a highly viscous pulp. The effect of shear thinning has resulted in improved adsorption kinetics resulting in higher carbon loading and reduced soluble gold loss. Total tonnage treated is approximately four million. Operating costs which include leasing and maintenance charges for the Filblast and pump power costs are about 16 cents per tonne. This is equivalent to about ten per cent of savings. Laboratory scale units having capacities up to 30 litres/min are available for test work but laboratory testing techniques so far developed do not accurately reflect the oxygen and cyanide savings which have been achieved in the plant.

Jan 1, 1994

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

By M Colwell

The Coal Mine Roof Rating (CMRR) is a rock (roof) mass classification (RMC) system/index that was originally developed by the United States Bureau of Mines (USBM) for aspects of underground coalmine geotechnical design and was first introduced to Australia as a part of the original Analysis of Longwall Tailgate Serviceability (ALTS) project conducted in 1997/1998. In subsequent years further refinement to its calculation was undertaken, such that the CMRR is now an industry standard for quantifying the structural competence of the primary bolted roadway roof interval and has been routinely/widely used by Australian collieries over the last 25 years with great success for roof support/chain pillar design. There have been many publications discussing the use and calculation of RMC systems and this paper also provides an important update and recommendations in how best to calculate the CMRR. However, it is rare to find an explanation as to why and how a RMC system/index satisfactorily takes account of the mechanics and rock mass behavioural issues associated with ground reinforcement. This paper provides such an explanation and insight with respect to the CMRR so it is: 1) better understood, 2) to allay any concerns, and therefore 3) will continue to be confidently used by and for the collieries’ benefit.

Nov 29, 2022

The sulphide ore occurring in the North Mine at Broken Hill is of a complex nature, consisting of an intimate mixture of argentiferous galena, marmatite (zinc-iron sulphide), and gangue minerals. A typical analysis of the ore is:Lead 15.2%Zinc 12.0%Iron 5.3%Manganese 0.8%Copper 0.1%Alumina 0.3%Lime 0.9%Sulphur 11.1%Insoluble 53.8%Carbon dioxide 0.3%Undetermined 0.2%Silver 9 oz. per tonTotal 100.0%The metallurgical practice for the recovery of the lead concentrate and zinc concentrate from the crude ore is briefly described in the following pages.(1) COARSE CRUSHING AND FINE GRINDING OF THE CRUDE OREThe crude ore from the mine, containing lumps to the size of, roughly, 10 in. x 8 in., is tipped over grizzlies with the bars spaced 3 in. apart; the oversize gravitating to a...

Jan 1, 1933