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By Russell P

Polyurethane resin (PUR) is extensively used in almost all coal producing countries. On the local scene, PUR components suitable for underground application were selected and subsequently, trials were carried out at several coal mines. This paper describes the work at Pikes Gully Colliery (B.P.3Coal), where water flow rates of up to 4.5 m (1000 gallons) per minute, were reduced to 1-1.5 m /minute at the tirst stage of application. Subsequent trials were carried out at West Cliff Colliery (Kembla Coal and Coke). A variety of PUR chemical mixtures were tested in coal ribs and in the roof of intersections and roadways. The trial results are presented with all particular details. Using the PUR injection method, the roof, at the most difficult intersection, was stabilised and 'de-bonded' roof bolts were re-sealed. At Pikes Gully and West Cliff Collieries, 2 tonnes and 3 tonnes of PUR chemicals were injected, respectively. The technique, primarily based on German experience (Bergwerksverband), was used by Delta Control Systems Pty. Ltd. ACIRL was closely associated with the trials, which were monitored by installation of the measuring Stations.

Jan 1, 1986

By B Howard, M Jones, D Pershke

"Current closure objectives and criteria are often difficult to achieve and are not delivering value for money outcomes at closure. Current mine closure processes tend to focus on rehabilitation and revegetation of landform structures to as close to premining condition as possible, rather than focusing on the functions of those structures and values they provided. Because mining has highly disturbed the environment, premining conditions and vegetation are often not achievable and objectives and criteria aimed at achieving close to these conditions have been shown to be very costly.The authors have developed a broader approach to developing mine closure plans that is based on environmental risk and gaining post-closure social, environmental and economic value. We think the focus should shift from trying to return the original landscape to returning functions and values provided on- and off-site. If it is not possible to return values on-site in a cost-effective manner, investment should be provided to deliver equivalent values elsewhere.This process can provide better stakeholder acceptance, deliver better environmental outcomes on the tenement and within the catchment and significantly reduce costs, whist fulfilling closure obligations.This framework should enable closure teams to: focus on the functions and services that are important to achieve as outcomes post-closure, rather than a focus on revegetation and replacing the premining biophysical structure engage meaningfully with stakeholders regarding closure outcomes and link outcomes to stakeholder values conduct transparent option evaluations that enable stakeholders to clearly understand the costs and benefits associated with each option and to participate in dialogue on option selection.We present examples of how the framework could be applied to identify alternate closure options that achieve equivalent value outcomes while reducing the costs of closing the mines.CITATION:Howard, B, Pershke, D and Jones, M, 2014. Achieving better mine closure outcomes for less money, in Proceedings Life-of-Mine 2014, pp 615–620 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 16, 2014

By DV Boger

Rheology is the science which deals with the deformation and flow of matter. Thus nccology is concerned with the flow of any material. The mining industry is concerned with digging things out of the ground, extracting the good stuff and throwing away the had stuff. In the upgrading processes associated with mining, is mineral processing, wet techniques are used where the primary material being handled is a particulate fluid, ie a suspension. After the processing operation, with the concentrates extracted, what is left behind generally is a wet material in suspension form, which may or may not contain reagents harmful to the environment. The amount of waste generated in any of the mining processes is large, in fact, the mining industry is the largest generator of solid waste in Australia. In order to minimise the waste generated within the industry it has become of interest to handle the particulate fluid wastes, or suspensions, at high concentrations, thus removing water and some of the reagents which may be harmful to the environment. The resultant highly concentrated suspension is a non-Newtonian hold Rheology deals with the flow of non-Newtonian fluids; therefore i combination of rheological understanding of high density suspensions. ill conjunction with an understanding of the environmental problems hero' faced by the mining industry, can and has led to improved methods of waste disposal in the industry, ie waste minimisation. This paper describes the progress that has been made in the development of dry disposal technology in the mining and minerals industry in Australia.

Jan 1, 1998

By I Lourel

In evaluating the installation of an in-pit crushing and conveying (IPCC) system for any mine, a number of options are available for each of the dig side, transport and dump side operations. Some of them are moreappropriate than others; given the pit arrangement, the material being handled and the rates at which it needs to be moved. This paper seeks to document the options that might be employed, and to rank them in terms of their applicability at any mine and their practicality overall, with a view to nominating those that would be most suitable for further study.

Jan 1, 2009

By Carthew J

For more than 30 years shearer loaders have been the most important winning machines for,longwall mining. While the machines of the first generation had a driving power of only 100 or so kW, the present day shearer loaders may be powered by more than 1000 kW. Daily outputs of 24000 tonnes have now been reached, but this still does not set a limit. If the deposit conditions allow, further increases are possible. This requires the optimum coordination of all system components. For this paper the use of coal plows has been of little import as plows have found no favour, and nor are they likely to do so in today's economics in Australian coal mining.

Jan 1, 1988

By Miller JD, Ye Y

The Air-Sparged Hydrocyclone (ASH) has been developed for the fast and efficient flotation of fine mineral particles in a centrifugal field during the past decade at the University of Utah. Over the years, the air-sparged hydrocyclone unit has shown promising potential for the flotation of copper porphyry ore, low-grade placer gold and auriferous pyrite ores, various industrial minerals, and fine coal cleaning. Many fundamental studies including the X-ray computed tomography (CT) analysis have been carried out in order to understand the multiphase fluid flow phenomena associated with ASH flotation. With data available from these studies, it is now possible to construct more accurate ASH flotation models for different applications in order to analyse the behaviour of the system and to optimise design and operating variables. The ASH flotation model developed in this paper is based on the data given in `Air-Sparged Hydrocyclone/Advanced Froth Flotation Fine Coal Cleaning', Final Report, DOE Contract No DE-AC-88PC88853, submitted by Pennsylvania Electric Company (PENELEC), December 1989. Data from several hundred experiments with the two-inch ASH-2C air-sparged hydrocyclone (capacity 0.1 - 0.3 tph dry coal) are available from the report and have been used for this analysis. In the past, a preliminary model based on limited data had been developed. The current study, however, emphasises the global behaviour of the ASH system by utilising almost all the data from the report for the purpose of scale-up and industrial application. There are two parts in the current modeling and analysis effort for ASH flotation of fine coal. The first part is the modeling/analysis of dimensionless ratio of overflow opening area to underflow opening area, A*, and the dimensionless ratio of air flowrate to slurry flowrate, Q . The second part involves the modelling/analysis of all other variables in the system and an expert system for operation and control is introduced.

Jan 1, 1993

By Wang SS, Frattaroll DR

In the development of novel sulfide collectors, especially for the low-lime and acid circuits, flotation of chalcopyrite, chalcocite, covellite and pyrite was studied with both new and commercially available S- containing collectors. The natural float- ability of sulfides, water quality, and redox potentials - all of which were considered im- portant in assessing collector strength and selectivity - were also investigated. Chalcopyrite exhibited the highest natural floatability. The response to most collectors, however, was chalcocite > covellite > chalcopyrite > pyrite. Water quality had a very significant effect on both natural and collector-aided floatability. De- ionized water and tap water had a flotation suppression effect compared with doubly- distilled water. Flotation results with single minerals are correlated with those for copper and pyrite from natural ores. Several novel collectors have now been developed for sulfide flotation in acid, neutral or mildly alkaline circuits. The results for four of these collectors, which have shown promise in commercial applications, are discussed in this paper.

Jan 1, 1986

By Pina P, Pereira MJ

The increasing exhaustion of raw materials entails the exploitation of poorer orebodies where the target mineral occurs frequently in a very fine dissemination. Consequently it is necessary to grind more and more fine to achieve an adequate mineral liberation. In other words, it is of fundamental importance to know what size one should grind in order to avoid the following detrimental situations: 1. Excessive grinding - giving rise to the generation of ultra-fine slime particles which may be lost in the ulterior concentration process and simultaneously leading to higher energy consumption. 2. Incomplete grinding - giving rise to insufficient liberation and consequently leading to considerable losses of the valuable components in the tailings. Although this issue constitutes one of the most important steps in mineral processing, little research has been done compared to other processes, mainly due to the fastidious experimental work required. This paper describes a complete and integrated system of image analysis, where some algorithms to determine automatically the degree of li beration, for different levels of grinding, are proposed. These algorithms, mainly based on mathematical morphology theory were tested with images obtained from polished sections of different grain size fractions. Cases studies on a complex sulphide ore from an important copper and tin deposit located in the South of Portugal are discussed. Samples of the unbroken ore are also studied by image analysis to predict the degree of liberation obtained according to the fineness of grinding.

Jan 1, 1993

By Koppe J. C

This study presents the procedure of mine modelling and reserve evaluation by means of statistics, computer interpolation methods and aerophotography interpretation. All data are from Carbonifera Treviso, Laura Muller City, Santa Catarina State, southernmost Brazil. From 22 bore holes and nine trenches opened in the coal seam outcrops, a data base including level references and thickness of all rock formations was created.Using this information, basic statistic analysis was carried out, showing that there are three different populations (three modal distribution). These populations defined three geological blocks with different characteristics of overburden removal and mining methodology. This mathematical approach for analysing geological data is very important for correct mine planning and complementary prospection.

Jan 1, 1993

On Monday, October 25th, 1971 at approximately 12.15 a.m. the night shift proceeding underground discovered smoke at No.1 and No-3 cut throughs on the eastern side of the belt heading and in close proximity to the upcast shaft. Attempts to control the fire continued throughout the morning; as the position underground altered various procedures were adopted in an effort to contain and control the fire. Despite these efforts at approx. 12.40 p.m. a sudden change occurred which made it necessary to withdraw all workmen from underground, the vicinity of the Tunnel entrances and upcast shaft. Sealing of the mine at the entrances was the only remaining alternative. Several boreholes were put down to enable sampling of the atmosphere and air temperatures to be taken. This was essential as a guide to determining when conditions were suitable to allow exploration of the area using mine rescue self contained breathing apparatus.

Jan 1, 1972

The Government Mining Engineer of South Africa has decided to legislate that Self Contained Self Rescuers (S.C.S.R.) become a mandatory piece of equipment for all those persons proceeding underground. It is envisaged that: * employees in underground coal mines will be fully equipped with S.C.S.R.s during 1988; * those persons employed in gold mines during 1988/89; and * personnel in all other mines by the end of 1990. It is the intention of this paper to discuss the introduction of these auxiliary life support systems, and to give an update on current market developments.

Jan 1, 1988

By Sengstock G. W, Spathis A. T

Benchmarks of mine equipment involved in the excavation process of coal mines would suggest that such equipment is not always operating at an optimum level. Dragline operations and truck/shovel operations rely on efficient use of their plant in order to maintain high mine throughput. The first process which affects the material to be excavated is the drilling and blasting process. Drilling and blasting delivers a fragmented material with a given disposition ready for excavation by mine equipment. As mine operators demand more productivity from their major excavating equipment, many sites are considering the use of productivity monitors to measure their outputs. Some of these productivity improvements will be directly related to the drilling and blasting process, so that as the monitoring systems improve, the opportunities to evaluate all drilling and blasting variables will also improve. This paper reviews current and newer methods for monitoring equipment productivity in mines. These include simple time and motion studies obtained by either manual timing of processes or by automated data collection equipment being adopted by the industry. Case studies for truck/shovel operations are discussed and the productivity improvements are compared with typical industry standards. These improvements relate specifically to parts of the load, haul and dump cycle and the potential for significant improvements are identified. Particular opportunities for drilling and blasting improvements are also presented.

Jan 1, 1995

By Ulvelin K, Antila K

Large scale cut and fill mining in narrow silver-lead-zinc orebodies began at Mount Isa in 1964. Initially each orebody was one stope and access was via raises from the level above. Upholing was the principal mining method, although flatbacking was employed where ground conditions were more difficult. Developments since have included access via footwall inclines and connection of all stopes with major crosscuts. Flatbacking is the principal method. The most recent cut and fill operation is now fully mechanised using drilling jumbos, rockbolting jumbos and load-haul-dump units. Improved ground support and drilling and blasting practices have enhanced safety, recovery and productivity in all cut and fill operations.

Jan 1, 1988

By W J Fisher

Northern Australia leads in world-class mineral deposits' is a bold statement. First there must be a starting point. Land north of the Tropic of Capricorn (23¦ 26' 5") will be regarded as Northern Australia covering nearly 40 per cent of the land surface of Australia. As opposed to land south of the Tropic of Capricorn, it should be regarded as Tropical Northern Australia and for the sake of brevity, (TNA) Refer Figure 1. Apart from the tyranny of distance from centres of power and population in the temperate zone, it suffered in the past from the belief that the tropics are unsuited for European workers and from the lack of infrastructure. Outstanding mineral deposits of iron, base metals, gold and diamonds, discovered and developed in the past three decades, provided the substance for the title. There are many world-class mines producing and there are mineral deposits neutralised through Government policy. TNA can maintain its lead in world-class mineral deposits provided Government policy will stop partitioning the land and decreasing that available for exploration. Let's look at what we have that is world-class. In Western TNA iron ore deposits at Paraburdoo, Mt Tom Price, Marandoo, gold at Telfer, diamonds at Argyle. In central TNA uranium at Ranger and Jabiluka, lead-zinc-silver at McArthur River, gold at the Tanami, manganese at Groote Eylandt and bauxite at Gove. In eastern TNA Mt Isa, Hilton, Century zinc-lead, bauxite at Weipa, gold at Kidston, Mt Leyshon, magnesite at Yamba and coal mines in the Bowen Basin. Those mines or deposits stand out yet are only an indication of the numerous lesser mines and of mineral deposits depending for development on market demand and/or changes in Government policy, eg 'The Three Mines' policy. Very large areas of mineral rich structures in the western, central and eastern parts of TNA are concealed below flat lying comparatively young unmineralised sediments. The Great Artisan basin sediments in eastern TNA can and do host oil shale and non metallic minerals. Nearly 40 per cent of western TNA is covered by the Great Sandy Desert. The Canning Track, with a series of 54 wells, was constructed by surveyor Alfred Canning in 1908 - 1910 with great difficulty. It extends 1700 kilometres from Halls Creek in the north to the gold town of Wiluna in the south, through the Great and Little Sandy Deserts. Gold explorers are following favourable structures extending to the north east below the sediments and sand hills covering the track. Half of central TNA's mineral structures are concealed by the Tanami desert and the Cretaceous sediments covering the pastoral regions of the Barkly Tableland and the Daly Waters to Top Springs pastoral areas. The Georgina Basin in the south eastern section is part of the concealment.

Jan 1, 1994

By A Manzoori, M T. Shadloo

This paper describes a CFD modelling study which was carried out to investigate possible improvements in the design of an alumina precipitator tank at the Jajarm plant of Iran Alumina Company. In particular, the tank has an impeller located very close to the tank bottom, such that it quickly becomes covered with settled solids after a shut-down of the agitator, making it difficult to restart. A CFD model was firstly set up in which the existing design was evaluated in terms of flow pattern, off-bottom suspension and distribution of solids, and power consumption. Further simulations were then carried out to test alternative designs, leading to a recommended design, which maintains good mixing, with the same power consumption and without the use of a low-clearance impeller.

Jan 1, 2006

It is no longer adequate in running mines and quarries to simply select the best equipment. Today's competitive international commodity markets demand superior efficiency. This requires efficient production and commercial processes together with systematic involvement of people in continuous improvement of processes. True Total Quality of Management (True TQM) principles provide an operating philosophy for maximising productivity and minimising unit costs of output. Unfortunately, even though these principles are proven in all industry sectors worldwide, they have not always been used correctly. This paper describes basic methodology for correct use of these principles to successfully improve the productivity of rock breakage production processes.

Jan 1, 1995

By Smele J. S, Dawes W. D

In recent years there has been a trend among mining companies to diversify exploration and development away from the countries that have dominated mining activity for the latter half of this century. With some exceptions, this trend is accelerating and is a function of the recognition that many parts of the world, with no previous exposure to modern exploration, are endowed with considerable mineral potential. In addition coincident with changing political and economic circumstances, many countries have recognised the benefits of attracting international mining investment and have radically changed policies, fiscal and legal regimes so as to encourage exploration and mining. Some countries, however, have not readily accepted mining for cultural or social reasons and have yet to make effective changes to mining legislation. For historical reasons, other countries may have little or no direct experience of western economics, nor may they fully recognise the need for stability and competitive fiscal and legal systems to attract foreign investment. Not all ventures in new countries have been commercial successes and there have been some lamentable and recent lapses from grace. Company strategies, company standards and management objectives can also vary widely from company to company. What may be an acceptable risk or rate of return for one may be completely

Jan 1, 1997

By Blain CF

For all mineral resource-based companies, it is important to reach the right balance of investment between acquisition and exploration to allow the best chance of achieving long-term corporate goals. The Broken Hill Proprietary Company Limited (BHP) provides an excellent example of success from generative exploration and supports the belief that exploration can be justified, not only in terms of investment criteria, but also because it is essential to a company wishing to build a dynamic profitable growth path based on world-class deposits as cheaply as possible. BHP was incorporated in 1885 to mine a lead/zinc/silver discovery at Broken Hill. The Company has since gone through a steel development phase (1911-1965) and is now in a major phase of growth partly based on exploration success. This third phase was marked by decisions taken in the 1950's to search actively for mineral and energy resources above and beyond the requirements of the steel industry. The commercial successes of this period have been Bass Strait oil and gas, Groote Eylandt manganese, Deepdale iron ore, Gregory coal and Carnilya East nickel. In total at least 22 new resource discoveries have been made in the last 25 years, of which 11 have been developed and several are undergoing feasibility studies. A financial analysis shows that the real value of the returns seeded by discovery covers the real exploration cost many times over. Moreover, the major discoveries have had a spectacular impact on the growth and development of the Company. BHP's present exploration effort is directed towards geological targets which most frequently meet attractive financial criteria and also promote diversification from steel-related earnings.

Jan 1, 1986

By L L. Kuhar

The AMIRA International P843A Geometallurgical Mapping and Mine Modelling (GeMIII) project is an interdisciplinary research collaboration between 17 global mineral companies and four research organisations aimed at providing support for the emerging industry trend of geometallurgy. The main aim of the project is to develop predictive geometallurgical indices which can be incorporated into a resource block model to maximise the commercial value of an orebody and to minimise the social and environmental impact of mining operations.Researchers at the Parker Centre/CSIRO have been focusing on the development of predictive hydrometallurgical indices for the GeMIII project via rapid, small-scale, cost-effective tests and protocols for comparative ranking of attributes relevant to leach performance. The focus of the small-scale leach tests has been to determine the leach index (relative indication of leach performance), recovery, impurity deportment, reagent consumption, effect of size/degree of liberation and mineralogy of samples for their relative ranking. Predictive tests for heap leach hydrology (related to agglomerate characteristics) and slurry rheological behaviour are also being developed.

Sep 5, 2011

By D Timms

The Kempfield deposit is located in the Hill End Trough, one of several intracratonic basins developed during Silurian–Devonian time, in the eastern province of the Lachlan Orogen, Eastern Australia.The deposit contains an oxide resource of 5.8 Mt @ 58 g/t Ag and a sulfide resource of 14.4 Mt @ 45 g/t Ag, 1.7 per cent Zn and 0.6 per cent Pb, classified and reported in compliance with the JORC Code. The deposit has been previously explored by a number of companies, including INCO, Shell, Jones Mining, Golden Cross Resources and recently Argent Minerals Ltd (Argent). Argent is currently completing a definitive feasibility study with a view to mining the deposit.The deposit is hosted at the boundary between the Molong High to the west, comprising Ordovician sediments and volcanic rocks and the Hill End Trough to the east, interpreted as a back-arc basin containing Silurian sediments and siliceous-feldspathic volcanic rocks. The boundary between these two strato tectonic units is an imbricate thrust fault zone known as the Copperhannia Thrust.The Kempfield deposit is hosted in felsic volcanic rocks known as the Kangaloolah Volcanics. These have been in-faulted and folded into the Middle Ordovician meta-sediments of the Coombing Formation of metasediments along the Copperhannia Thrust. The Kangaloolah Volcanics belong to the Late Silurian Mumbil Group, comprising submarine carbonate-shale facies interspersed with extensive felsic volcanic piles, which grade conformably upwards into turbiditic sandstone and siltstone sequences (interpreted to represent a deeper depositional environment). These turbiditic rocks are known as the Campbells Formation, comprising siltstone, sandstone and andesitic tuff. The rocks at Kempfield are metamorphosed to lower greenschist facies, reflected through the different type of schists.Silver, gold, lead, zinc mineralisation is hosted in barite-rich horizons, near the boundary to quartz-phyric tuffaceous rocks in submarine, immature, reworked felsic ash tuffs. Barite appears to be hosted in greatest concentrations by the coarser grained volcanoclastic sandstones and grits, whilst intercalated siltstones are volumetrically minor and tend to return low barite and silver. Mineralisation is hosted in stratiform and probably stratabound barite-rich horizons. A northeast-trending, steeply dipping, metamorphic cleavage (S1) occurs throughout the project area.

Aug 22, 2011