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In December 1997, a series of new environmental legislation was enacted including:ò Environmental Planning andAssessmentAmendmentAct 1997; ò Contaminated Land ManagementAct 1997;ò Protection of the Environment (Operations) Act 1997; ò Native Vegetation Conservation Act 1997; andò Pollution Control (Load Based Licensing) Act 1997.These new Acts will have varying degrees of impact on the coal mining industry in New South Wales when they commence later this year.

Jan 1, 1998

Roadheader tunnelling machines have been used in Australia by both mining companies and contractors involved in the mining and con- struction industries since the early 1970's. They have both advantages and limitations, and this paper discusses machine excavation from the point of view of a contractor who has both reaped the benefits and suffered the conse- quences of using roadheaders. The paper also includes brief descriptions of three projects tackled by roadheader, all the projects being Declines.

Jan 1, 1987

The coastline is. an incomparable stretch of sea coast known as Ninety Mile Beach. Two gas pipelines and two oil pipelines carrying hydrocarbons from thb'Bass Strait fields to the markets of Australia cross this beach. They cannot be seen as they are laid in trenching stretch- ing many miles out to sea and the beach was restored to its natural state. Even where the dunes were disturbed, suitable grass was sown thus consolidating the sand and preventing erosion. Ninety Mile Beach is but one of the many key.wildlife and recreational areas that our operations must be concerned with. Others include Westernport and Corner Inlet, but the one discussed in this paper in particular is the platform area of the Bass Strait itself. Never was the old adage "an ounce of prevention is worth a pound of cure" more meaningful than in offshore oil production. All are well aware of some of the events of the past several years that resulted in large and costly oil spills. Far less is known, seen or publicised about the measures and developments that are undertaken to ensure that such events do not occur. We also have well developed plans for response in the event of an emergency situation, which can be initiated with great rapidity. Our responsibility is to ensure that with the best of engineering technology and operating procedures, spills do not occur.

Jan 1, 1971

By Torres F, Cerda I, Gimenez P, Gonzalez G, Castelli L

Slurry density measurement, specially in cyclone feed streams, is fundamental to grinding circuit control. With the purpose of increasing the availability of such a measurement, the design of a soft-sensor in an actual grinding plant is addressed in this paper. The system is designed to substitute the momentary unavailability of the real density sensor, either because it has failed or because it has been removed for any other reason. The ARMAX model structure is determined using the stepwise regression method. Starting with a list of the candidate variables, the method selects, one by one, and in a systematic manner the variables which best model the measurement to be replaced, choosing them from the set of presumably correlated candidate variables. In this paper not only the single measurements are included in the list of candidates, but also combinations of such measurements having physical significance. A phenomenological model has been built with the purpose of determining these combinations. It turned out that in most of the cases the components of combined measurements having physical significance were selected by the stepwise regression method, instead of the single measurements. Actual grinding plant data is used to determine the model structure, to estimate the model parameters and to test the predictive capability of the developed soft-sensors. Good results are shown to be obtained during periods of up to 30 hours of the density soft-sensor operation.

Jan 1, 1995

By Rashchenko AF, Voiloshnikov GI, Elshin VV, Khomutov VV

The sorption method for the precious metals recovery fromsolutions and pulps are a perspective trend of modernhydrometallurgy. Russian gold mining industry uses thesemethods, anion-exchange resins being applied as sorbents. Theanion exchange resins allow effective recovery of preciousmetals, however, they have several drawbacks as compared withactivated carbons: high cost of sorbents; difficulties arisingduring treatment of pulps with complex ion composition;necessity of using titanic equipment and thiourea for gold elutionfrom loaded anion-exchange resin and its regeneration.

Jan 1, 1993

Australian continental crust has accreted and consolidated by thirds: 1/3 during Archean time, 1/3 during Early to mid-Proterozoic time, and 1/3 during latest Precambrian to mostly Paleozoic time. The progression of orogenic systems and the crustal consolidations they represent seem not fundamentally different in basic orogenic processes from better known Mesozoic-Cenozoic examples in that accretionary, continental margin, collisional, and intraplate intracratonic inverted and/or reactivated systems are all recognizable in the tectonic evolution ofAustralia.

Jan 1, 1995

By Taylor GP

Mining Lease SML 57 was registered to Mount Kasi on 5 January, 1995. The Mount Kasi gold mine is located in Vanua Levu, Fiji's second largest island and operated from 1932 to 1946 producing 261,000t of ore at an average grade of 7.5g/t Au. The deposit represents a structurally controlled style of high sulphidation copper gold mineralisation with peripheral low sulphidation mesothermal vein type gold mineralisation. The resource consists of 1,048,000 tonnes of residual soils (eluvium) containing 1.9 g/t Au at 0.5 g/t Au cut off and 1,240,000 tonnes of hard rock at 3.0 g/t Au and 1.0 g/t Au cut. 94 drill holes, 298 auger holes and 85 pits were modelled to outline the resource. 29% of the pits bottomed in mineralisation and it is likely the full thickness of eluvium has been understated. The pit is scheduled to produce 500,000 tonnes of ore per annum to yield 35,000 ounces of gold with an initial 2 years of eluvial ore followed by a further 2 years of hard rock ore. Total capital costs are estimated to be less than 10.0 million dollars with construction planned to commence in 1995. The likelihood of locating further ore is high.

Jan 1, 1995

By M W. I Visser Æt Hooft, R C. Schimmel

Until recently the Corus IJmuiden pellet plant produced approximately 4.5 Mtpa of pellets. Corus IJmuiden is currently running a program to increase its pig iron production to 6.4 million tonnes HM per annum. The burden of the Corus IJmuiden blast furnaces consists of approximately 50 per cent high basicity sinter and 50 per cent acid pellets, both produced in-house. To accommodate the increased pig iron production, the capacity of the pellet plant needed to be increased to 5.0 Mtpa. The productivity was increased by modifications to the plant layout, which were implemented during the 2006 cold maintenance stop. In addition, the composition of the ore blends is optimised to gain productivity.

Jan 1, 2007

By Jacobs M

After a methane explosion in a coal mine a pre-determined crisis management procedure is instigated. As the process rapidly evolves the inevitable question arises - are personnel trapped underground, are they alive and can they be rescued without putting the lives of the rescue crew at risk? This is a very emotive question with many sub-questions such as; could anybody have survived, is there the potential for a secondary explosion and is there a `window of opportunity' before that secondary explosion occurs?To determine if that window of opportunity exists two fundamental elements must be in place; a method of determining the atmosphere at key points in the mine and a method of predicting the course of change of that atmosphere with respect to time. The first element can be achieved if the tube bundle system is intact and drawing samples from known points, alternatively boreholes can be drilled from the surface. The second element can be realised by utilising a sequence of computer generated control charts which have a time axis, a percentage combustibles axis, the upper and lower explosive limits of the current atmosphere and a prediction option which allows the user to look at the potential changes in the atmosphere over a set period of time. These control charts would be part of the mines on-going crisis management system rather than a tool to be used after an explosion had occurred.

Jan 1, 1998

For the mineral industry, sustainability seems to mean socially positive and ecologically neutral mineral extraction. Mines are financed and developed in response to demand for their products. The purpose of my paper is to indicate the potential dimension of demand. As part of an unrelated study which I undertook ten years ago, it became apparent that there is a persistent relationship within communities between infant mortality and mineral use; greater mineral use corresponds to a lower rate of infant mortality. This comes as no surprise; sufficient potable water, a reliable supply of food, hygienic waste disposal, hot water and refrigeration all improve the chances of survival of the more vulnerable members of any community. The predictable provision of these facilities requires the application of minerals. This relationship is supported by a table (Appendix 1) included in the UNICEF publication, æThe State of the WorldÆs Children 2001Æ. This table lists regional infant mortality rate (IMR) statistics from around the world, including a listing for æindustrialised countriesÆ. Such countries experience an IMR lower by an order of magnitude than any other region. æIndustrialisedÆ inevitably involves the use of metallic and energy minerals. The principal use of copper is in the generation and distribution of power; it is fundamental to any industrialisation. IMR is a valuable connection because it quantifies caring for the young, a vital strategic driver of human behaviour independent of time, place, fashion or economic circumstances. I have tabulated the population, IMR and the copper demand per head of population for countries containing over 99 per cent of the population of the world in the years 1950, 1960, 1970, 1980, 1989, and 1999. These countries have been consolidated into four groups, Very High, High, Medium and Low rates of infant mortality (UNICEF has used this terminology; the Low group includes all the æindustrialised countriesÆ). The purpose of this consolidation was to reduce the volume of work, to dampen out the impact of regional wars and business cycles, and to dampen out the variable quality of information. Based on the pattern of the copper demand, population and IMR over the last 50 years, I have projected the likely copper demand in 50 years time. A dominant feature of my tabulation is the increase per decade in copper use per head and a corresponding reduction of the IMR. The word æuseÆ is preferred to æconsumptionÆ because it is estimated that over 80 per cent of all the copper ever mined is still in circulation There are two major influences at work; one is the absolute increase in population (UN estimates for 2050 are updated periodically) and the second is the movement of countries into a higher pattern of use and lower IMR. For example the Medium group in 1989 had an infant mortality rate approximating that of the Low group in 1960. With the population of the Medium group (which includes Russia and China) forecast to reach 2.6 billion in 2050, the world copper demand in that year will be significantly greater than the present figure. Nevertheless it will not be as great relatively as the increase of over 300 per cent in the last 50 years.

Jan 1, 2002

By P Gilroy

In recent technical investigations that were triggered from ore for rail shortfalls at Yandi, BHP Iron ore has identified a gap in resource knowledge relating to geo-metallurgical characteristics that predict materials handling performance and throughput. Within these investigations BHP has learnt that this lack of resource knowledge has translated to a lack of predictability associated with mine planning inputs which has resulted in poor compliance to plan and deviation management practices. A business value chain was developed in an attempt to identify the best possible solution to unlock this resource knowledge in the short, medium and long term planning horizons. A fast fail approach was taken with the implementation of hyperspectral blasthole analysis, which was chosen to deliver the best possible value driver for the asset. This report will detail the Yandi journey in expanding the hyperspectral and geo-metallurgical value chain, unlocking resource knowledge along the way. CITATION: Gilroy, P, 2018. Development of an empirical geo-metallurgical model that unlocks value of the mineral resources at Yandi Mine, in Proceedings Complex Orebodies Conference 2018, pp 85–87 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

By Quayle J. E

This paper covers period from 1973 through to 1988 and the mines of West Coast Mines, Elur Mine, North Mine and Risdon Zinc Smelter, now all part of the Pasminco Group. During this period, optimisation started with one mine (West Coast Mines) producing four Product concentrates with constant steady feed to the smelter and progressed to three mines producing eight products and a smelter varying feed inputs to maximise benefits. The initial optimisation was done manually using a desk top calculator and hand drawn graphs. This ultimately advanced to the use of PC plus linear programming software and spreadsheet generating relevant graphics. The financial benefits were achieved with no capital expenditure and increased from an initial $0.5 to $1.0 M/year (1973 $'s) to $5 to $10 M/year (1988 $'s).

Jan 1, 1991

Chromite ores have a long history of low pricing and for AustraliaÆs only chromite mine this has been a particularly tough challenge, especially as the mine is located nearly 400 km from the nearest port at Port Hedland. A stockpile of chromite fines (-16 mm) has been built up since 2003. The opportunity to develop a facility to treat this material to produce a chip (-16 + 1 mm) product and a sands (-1 mm + 45 micron) product was taken when the price increased to above US$140/t. A simple add-on plant containing a heavy media cyclone circuit for the chips and a spiral circuit for the sands was designed and developed. During construction of the fines plant the price of chromite reached a level where the payback for the entire project was less than eight weeks. Soon afterwards the price and the demand for chromite plummeted and the site was put on care and maintenance, except for the commissioning of the fines plant. This put considerable pressure on whether to continue to operate the plant or to place it in care and maintenance. Times of boom and bust provide management with almost totally opposite views. By not taking a conservative view on prices and costs, the effect of extremely low prices and minimal demand can be devastating to a good project. Designing and building plants with conservative costings in boom times gives a greater chance of keeping projects alive during the bust periods that tend to follow.

Jan 1, 2009

By S Khadhraoui, T Yusuf, C Kirmse, E Hecker, R Degel, A Akouch, N Borowski, M Reuter

For an optimal design and control of metallurgical processes, a deep understanding of the thermodynamics of the governing reactions is required. Modelling the thermochemical behaviour of those reactions is complex, as it involves multi-component and multi-phase systems. For this purpose, thermodynamic computing systems such as FactSage™ (Bale et al, 2016), which combine Gibbs energy minimisation routines with large databases of optimised thermodynamic data of solutions and compounds, have been used within the SMS group GmbH. Recently, the successful integration of those thermodynamic computing systems into the digital platforms of SMS has been achieved through ChemApp, which made running complex thermochemical calculations in Python-integrated development environments possible. ChemApp is a programmer’s package for thermochemistry and incorporates the Gibbs energy minimiser of FactSage™ as reported by Petersen and Hack (2007) as well as by Zietsman and Petersen (2018). The digital platforms link the fundamental and the industrial aspects together and can be applied as a process advisor, or for the evaluation of the environmental footprint and the economic implications of different process routes, as discussed by Reuter (2023). Two examples illustrating the progress of the developments in this regard will be introduced: 1. The Tilting Refining Furnace (TRF) for copper scrap recycling and refining to anode copper (the BlueControlApp). 2. Dephosphorisation control for the oxygen steelmaking process (Basic Oxygen Furnace (BOF)).

Jun 19, 2024

By Tsuchida N

The history of world nickel production has been affected significantly by the supply and demand situation and fluctuation of LME price of nickel metal. In the beginning of the 1980s, the decline of price and demand lead to the withdrawal of un-competitive producers and the shrinkage of the production capacity. During the same period, Sumitomo Metal Mining maintained the production level with continuous improvement of the traditional matte electrorefining process. However, Sumitomo has recognised that the continuous improvement alone does not promise us the ability to catch up with rapid changes in the world. In the meantime, Sumitomo intensively researched chloride hydrometallurgy and has developed the chloride process for the nickel refining. This includes the solvent extraction and chloride electrowinning in the mixed sulphide process and the chlorine leach of the anode slime arising from matte electrorefining. In the late-1980s, Sumitomo Metal Mining decided to develop a new nickel refining technology based on chloride hydrometallurgy. The new process was designed from the comprehensive aspects involving safety and the environment. Construction of the plant for the matte chlorine leach electrowinning (MCLE) process was commenced in 1991. The MCLE plant with a capacity to 2000 tonnes per month has been commissioned at Niihama since 1992. The process has provided high productivity, overall good economics and high quality of electrolytic nickel produced. After the establishment of the process, Sumitomo has maintained continuous improvement of the new process and has attained the best practice of the work classification.

Jan 1, 1996

By Yoshii Y

Many kinds of shield machines are being driven in the soft ground of Tokyo metropolitan area. Tunnel alignments for underground power transmission lines are generally planned to pass under public roads where facilities, especially life-line facilities, are densely located. Therefore, it is frequently required to drive the shield machines along very sharply curving routes. This paper reports on the performance of the new shield machine - the Sharp Curve Excavation Shield Machine - developed by Tokyo Electric Power Co., Inc., which can freely drive along a much sharper curve than conventional machines. Some of features of the developed devices of this machine are, maximum flexing angle of 6.5 degree in all deirection at the middle of shield body, maximum bending angle of 3.5 degree in all direction at the cutter disc, and so on. This shield machine can there- fore drive along curve of minimum radius 15m. The machine was confidently applied to the const- ruction of tunnel in soft clay strata at N values 2 to 5. Outer diameter 3.7m. Length 202m. Horizontal curve; radius 15m, length 20m x 2. Vertical curve; radius 30 m, inclined driven up 29%. The behaviors of the shield machine, segments and surrounding ground were monitored during construction for safety and efficiency check of this machine.

Jan 1, 1987

The Rotary Kiln at TeKumi was commissioned in February 2002. The process involves burning limestone at 1000 - 11 000¦C to produce a burnt lime (CaO) product. This paper describes the design and installation of a trifoil system to improve the energy efficiency of the kiln. An energy balance showed that 32 per cent of the energy was being lost through the flue gases, compared to 5.8 per cent in shell losses and 2.5 per cent lost as heat in the product. The trifoil proved to be the best way to tap the energy from the flue gases. Drying tests showed that a trifoil improved the drying time of limestone by 37.5 per cent, compared to only 25 per cent for a lifter system. The trifoil system increases the surface area for heat transfer in a Rotary Kiln by 180 per cent. The overal energy efficiency of the Rotary Kiln was improved by 15 per cent, resulting in a 15 per cent increase in production and an 80¦C reduction in flue gas temperature. This has reduced dust build up in the ducting while reducing maintenance costs through a reduced fan speed. The trifoil hub was designed with tooths at the centre to prevent shifting. Each trifoil leg has an anchor block on the down side to prevent downward movement of the trefoil legs.

Jan 1, 2003

In the introduction to a recent paper dealing with, the relationships of magnetite and hematite in the banded iron formations or "jasper bars" of the Western Australian pre-Cambrian(17)t the author made a brief mention of these interesting rocks, of the principal series in which they occur and of a few of the rock and mineral types to be found within them.He drew attention to the essential shnilarity of these Western Australian banded iron formations to those of the pre-Cambrian of such other countries as the United States Lake Superior region, Sweden, South Russia, India, South Africa and Brazil, and gave a brief summary of his views as to the origin of the formations in Western Australia. Furthermore he stated that the banded iron formations have proved of considerable direct economic importance in the goldfields and other' regions of Western Australia, and he referred to the assistance they have provided the field geologist in geological mapping and the determination of geological structures.It is in elaboration of this last statement that the present paper has been written. In the following pages will be found some examples of the use to which the jasper bars have been put in the determination of the geological structure of critical areas in the goldfields of the State.Firstly, however, it may be as well to recapitulate the features of interest in these rocks. The true jasper bars or banded iron formations including the types jaspilite, banded hematite quartzite and banded magnetite quartzite or chert, together with their higher grade metamorphic derivatives such as banded magnetite-gruneri~ quartzites, magnetitegrunerite schists, fayalite ,and hedenbergite bearing handed magnetitegrunerite quartz rocks and' to 'a lesser extent magnetite-hypersthene grunerite quartz rocks, are abundant in the older series of the Western Australian pre-Cambrian. They are best developed in the older Greenstone or Kalgoorlie series of the goldfields districts, interbedded with metamorphosed basic lavas, tuffs and sediments. The mineralogy andpetrology of these rocks, the history of their metamorphism and their origin have been discusseq elsewhere in some detail by the author(19), (20). In one of the papers(20) it was clearly demonstrated that in the light of the true facts the old silicified shear zone theory of the origin of the jasper bars is quite untenable and that the formations undoubtedly represent sedimentary horizons as was recently pointed out by McKinstry(14).It has also been shown that banded ferruginous cherts, quartzites and cherty carbonate rocks of much lower metamorphic grade are well developed...

Jan 1, 1943

By Woodcock JT, La Broody SR

As part of a project on the application of thiourea leaching to a variety of Australian ores, the systematic variation of pH, redox po- tential, and thiourea concentration were in- vestigated on an oxidized gold ore from the Nevoria mine, WA. Stirred open beaker tests were conducted with a pH-stat and Eh-stat system to automati- cally control pH and redox potential at selected values, while thiourea concentration was main- tained manually. Increasing the acidity of the leach liquor from pH 3.6 to pH 1, increased the gold extrac- tion from 37 per cent to over 90 per cent in S h, but there was only a limited improvement below pH 1.5. Silver extraction and thiourea consumption increased as the acidity was in- creased. Increasing the redox potential from 150 to 200 mV (i.e. potential of Pt electrode vs SCE) increased the initial rate of gold and silver extraction, but the effect on cumulative gold extraction by 5 h was slight. Thiourea consump- tion was greatly increased as the redox poten- tial was increased. An increase in thiourea concentration from 1.2 to 4.8 per cent increased the initial rates of gold and silver extraction, but, as for the change in Eh, the improvement in cumulative ex- traction by 5 h was marginal. Thiourea consump- tion increased with thiourea concentration.

Jan 1, 1984

By H Indirawati, R Ayres, A Nur Kasnanto, S Konopa

As a project moves through the mine life cycle, the quantity of data available increases and the understanding of the orebody matures. Incorporating new information quickly and efficiently in current 3D models, is essential for adding value across the life-of-mine value chain. At the Martabe Gold Mine, the resource development group manages 14 drill rigs on six resource projects, including three operating mines. The Martabe deposits are geologically complex and the volume of new information that becomes available each day is substantial. It is imperative that new geological and assay information is integrated into the 3D models as soon as possible, so that drill planning and targeting can be modified accordingly. Martabe uses Leapfrog<sup>®</sup> 3D software to update and interrogate the 3D models on a dynamic basis as data becomes available. This results in faster and more effective changes to drill planning and schedules. The impact of this is better drill productivity and cost savings due to optimal drill targeting, and availability of up-to-date models incorporating the most current data. CITATION: Konopa, S, Ayres, R, Nur Kasnanto, A and Indirawati, H, 2018. Optimised drill targeting using dynamic 3D modelling, Martabe Gold Mine, Indonesia, in Proceedings Complex Orebodies Conference 2018, pp 99–101 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018