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By Lama R. D

The Australian underground coal mining industry is undergoing major changes. This paper analyses the technologies presently being researched in mines, and discusses their utilisation as major contributors in the underground mining of coal in Australia over the next 20 years. It describes the problems that underground mining of the year 2000 will face and the possible solutions to those problems based upon results of present day research. Methods, equipment and organisational requirements are outlined. Developments in micro-electronics, computerisation and monitoring will require a new look into human resource development, education and training, and organisation to meet the challenges of the 21st century. The mining system's philosophies of the future are Outlined.

Jan 1, 1986

The phosphatic overburden of Christmas Island is a lateritic soil and consists dominantly of crandallite and millisite. These minerals are polymorphs of general formula, (Na,K)x Ca2-x (Al, Fe)6 (PO4)4 (OH)10-x (2+x) H2O. Iron occurs only in millisite. Both minerals exhibit similar thermal transformations, dehydroxylating near 600¦C and recrystallizing above 800¦C. Dehydroxylation results in crystal structure collapse but retention of crystal morphology. Ggethite, boehmite and apatite are minor constituents of some-of the phosphatic Soils.

Jan 1, 1971

A simple production technique has been initiated and implemented at Oaky Creek open cut coal mine to optimise recovery of coal from the relatively thin geological seams. The production technique is based upon minimising coal dilution through careful dragline operation and the selective use of mine mobile equipment to clean the top of coal. In addition, recovery of coal from the pits has been increased by refining blasting and dragline methods.The implementation of the recovery optimisation programme at Oaky Creek has provided significant economic benefits from increased yield through the preparation plant by the reduction in dilution, and from increased raw coal tonnage through improved pit recovery methods.

Jan 1, 1990

By Robbilliard K. R, Floyd J. M

The problems facing the metallurgical industry from the viewpoint of the range of unacceptable residues, flue dusts and slags currently produced from the electrolytic zinc process, electric arc furnace scrap treatment, and blast furnace operation in lead smelting and the Imperial Smelting Process (ISP) are addressed. The application of the Ausmelt technology is discussed and analysed for the pyrometallurgical treatment of zinc plant residues, steel plant flue dusts and lead blast furnace and ISP slags, as well as the more complex issue of smelter modernisation to avoid production of zinc plant residues in the future. Processes developed from pilot work are described and indications of the economics of treatment of electrolytic zinc plant neutral residue and jarosite are given.

Jan 1, 1993

By Nichol R

- PART A The Hoppers Crossing Pumping Station is one of the principal components of the Western Trunk Sewer Project which replaces the 90 year old Main Outfall Sewer and will convey 60% of Melbourne's sewage flow from Brooklyn to the Board's Farm at

Jan 1, 1987

By Wood CJ, Davis JJ, Askew H

A dynamic model of a dense medium circuit has been developed and tested against plant data. The model shows the response of the circuit to both controlled (changes in specific gravity set point or changes in circuit coal feed rate) and uncontrolled changes (changes in raw coal moisture, loss of raw coal feed) in operating conditions. The model is built up from dynamic models of the individual sumps, pumps, pipes, splitters, magnetic separators and automatic controllers in the circuit. The model can be used for design of automatic control loops and for investigation of possible process modifications such as changes in water addition points. This paper describes the model construction, the testing of the model against actual plant data and gives some examples of its use in investigating plant response to changes in operating conditions.

Jan 1, 1978

How do you initiate closure planning for a mine site that is on the doorstep of a major community without generating the extremes of panic or complacency? That is the question that is faced by Australia's largest gold mine, the Kalgoorlie Consolidated Gold Mines (KCGM) Super Pit in Kalgoorlie-Boulder. KCGM's Community Relations Manager, Danielle van Kampen, will reveal the lengthy closure planning process that is in train to alert yet not alarm the community about the future of the Super Pit and to generate discussion on issues of importance. What will happen to the 'big hole' that generates both mining and tourism dollars for the City of Kalgoorlie-Boulder as its anticipated closure date of 2021 comes closer? How do you communicate a constantly evolving closure date? Although the process may generate more questions than answers, the project will be discussed at length and with the added benefit of independent community recent research in the form of the public 2009 Closure Consultation and the KCGM 2010 Social Impact Assessment. This is an ABSTRACT ONLY no paper was prepared for this presentation.

Jun 1, 2010

By Wood P. D, Pettifer G. R

In the upper coal surface in the Latrobe Valley, craters known locally as fireholes have developed due to prehistoric coal fires. They can be several hundred metres across and up to fifty metres deep, and are now filled with overburden materials varying from hard baked clays to very soft lacustrine clays. In addition to reducing coal reserves, continuous mining operations are seriously affected by fireholes. Large undulations in the upper coal surface result in a mixture of coal and overburden on the upper mining levels. The very soft lacustrine clays are unstable in the mine batters and the overburden dump, are difficult to handle on the bucket wheel excavator/conveyer system, and have insufficient bearing capacity for the large bucket wheel excavators. Early identification is essen- tial and both drilling and dynamic core penetrometer have been exten- sively used. However, this has not proved adequate in locating and defining the extent of all fireholes, due largely to their irregular shape. To overcome this a range of geophysical techniques has been trialled with very promising results. A trial area has been covered on a twenty metre grid using gravity and Geonics EM34 conductivity measurements and the same area has been covered at a closer spacing with high resolution magnetics. Image processing of contoured magnetic, EM34 conductivity and residual gravity data has resulted in very good correlation with drilling data.

Jan 1, 1989

DURING the four years, 1922, 1923, 1924, and 1925, China produced the following quantities of non-ferrous metals and ores: Antimony Products - 67,869 (long) tons. The production for 1925 was 20,869 tons, of which 80% was regulus, 14% crude,and 6% oxide.Arsenic (White) - 4200 tons. The production for 1925 was 1200 tons, but only 90 tons were exported, some 25% of which to Hong-Kong, France, and U.S.A. each, and the rest in small lots to other countries. Domestic consumption was 1110 tons, and thelocal price for "cake" was around £47 per ton on 1925 exchange.Arsenic Ore (Realgar) - 1400 tons.Lead Ore (Galena) - 44,853 tons. The production for 1925 was 10,853 tons, of which 16%, produced in Korea, went to Japan, and 84% produced in Hunan, went to Europe.Manganese Ore (Pyrolusite) - 142,567 tons. The production for 1925 was 42,567 tons, of which 94.3% went to Japan.Tin Ingot - 33,480 tons. In 1925 the exports to Hong-Kong were 8880 tons of usual rough tin of 94% to 96%. Most of this was refined to No. I Chinese quality of 99.3% and exported to U.S.A. and Europe, owing to the good price ruling.Sulphur - 12,000 tons. Sulphur is included in this list in order to explain how its production led to the discovery of some other ores.Wolfram - 19,668 tons. The production in 1925 was 5868 tons, most of which came from the Quee Mee mountain district in South Kiangsi, from the detrital deposits. Civil disturbances prevented the usual output from Hunan border.Zinc Ore (Blende) - 134,190 tons. Exports for 1925 were 34,190 tons of low-grade ore, averaging 30% zinc, 14% lead, and 7% silver...

Jan 1, 1927

By Frew J. A, Harris M. C, Manlapig E. V

The recovery achieved in a flotation process is a function of both the characteristics of the feed stream and the operating conditions within the flotation cell. In this paper, the flotation characteristics of the streams within the Red Dog le

Jan 1, 1997

By Reeves I. And Farquhar J, Pearce S

The irregular shape of the Rosebery orebody, coupled with the inconsistencies in grade over short strike lengths, has meant stoping blocks have had to be small to combat dilution and stability problems. In the past, each lens was divided into regular block sizes and developed up to five years before production commenced. There were two major drawbacks to this practice; firstly, existing development deteriorated over time therefore requiring rehabilitation prior to production. Secondly, the pre-determined blocks could not be easily changed to incorporate changes in mining technology or economic circumstances. Bearing these problems in mind, it was evident that any new lens development had to be designed to allow maximum flexibility. The lens being currently developed is J lens. It represents approximately 50 per cent of the current reserves tonnes, and 65 per cent of the zinc metal. Its importance to the mine's future cannot be over emphasised. At its core the lens is up to 25 m thick at grades of over 30 per cent zinc. The practice of dividing the orebody into levels and sublevels, with consequent crowns was no longer acceptable because of restrictions in stope design and potential loss of ore. To assist in the development planning of J lens, a geostatistical block model was applied in long section to graphically represent the lens. Areas of high zinc concentration, as well as zones of uneconomic material were identified by using the model. This has meant that the development could he targeted, enabling stope delineation to occur in the lens without significant ore loss. Because of limited development resources, and the need to bring J lens on-line in the near future, the development strategy has had to focus on 'just-in-time' principles, rather than accessing the whole lens from bottom, and progressing upwards. Tight development schedules have required individual stoping block to be developed on such factors as grade and available tonnes rather than as a vertical sequence.

Jan 1, 1993

Mineral sands are different to almost any other commodity; however, it shares similarities with other commodity types, such as the importance of quality constraints of iron ore and coal or the importance of physical properties of diamonds. The mineral sands industry consists of two principal product streams; titanium dioxide minerals û in the form of rutile, ilmenite and leucoxene, and zircon. The principal valuable heavy minerals (VHM) include ilmenite, leucoxene, rutile and zircon. Variations of other titanium minerals occur between the end members of ilmenite and rutile, including pseudo rutile and anatase. Most mineral sands deposits are found in unconsolidated fossil shorelines several hundreds of metres to tens of kilometres and occasionally hundreds of kilometres inland from the present coastline. Mineral sands orebodies essentially fall into two categories based on the mode of deposition: alluvial or aeolian. Alluvial deposits are further split into marine beach placers (or strandlines) and lacustrine heavy mineral (HM) accumulations. Exploration for mineral sands involves the positive identification of key criteria leading to the focus of exploratory surface sampling, augering and drilling. Assaying is primarily focused around determining the percentage of HM contained within a given sample. Other results of interest include clay fines, sand and oversize. Metallurgical/mineralogical assessment is often undertaken via laboratory scale bench tests that replicate the wet concentration and dry mill processing routes. The most critical component in resource assessment for mineral sands is about quantifying HM grade, then mineralogical assemblage and then quality of those mineral species. This will determine whether a mineral sand final product is marketable or not. Mining of mineral sands is conducted either wet or dry. Wet methods are generally preferred for large tonnage, unconsolidated and low clay orebodies. Where ground conditions are hard and orebodies are small, high grade and discontinuous, dry mining techniques are generally employed. Concentration of mineral sands from the primary ore is carried out in two sections; wet, utilising sizing and gravity differentiation between HM, VHM, clay and quartz, and dry, exploiting the magnetic, electrostatic and to a lesser extent specific gravity (SG) properties of the minerals of interest. Mineral sands exploration, mining and processing faces the same operating challenges as the rest of the resource sector. Added to this are the issues that are unique to mineral sands and to which the industry devotes considerable resources to developing solutions.

Jan 1, 2009

By Gupta A, Fung C. C

The hydrocyclone parameter d5Oc is estimated by the application of Artificial Neural Network (ANN). Results indicate that ANN performs equally well as compared to statically derived analytical formulae. Results also show that ANN will also be convenient in the on-line control of hydrocyclones.

Jan 1, 1996

By Morrison RD, Peberdy NJ

Simulator training provides a cost effective method of training operators in both the process and control aspects of a metallurgical plant. The components and requirements of a training simulator are described along with the benefits to be gained from simulator training. A table summarizing some applications of metallurgical training simulators is Given.

Jan 1, 1991

By Thompson D, Somerville JM, Brock DA

The development of a softwood alternative to the hardwood chockpiece used to build the waste-edge breakers commonly incorporated in gateroad packs is described. The results of laboratory tests on softwood prototypes and two underground trials are presented. The results of the last trial suggest that a viable alternative chockpiece has been designed, offering advantages over availability of wood, weight and given reduced wood content, price.

Jan 1, 1992

By Myers I. A, Peters S. G, Bultitude R. J, Dowling K

Gold-quartz and antimony-gold-quartz veins in the Hodgkinson Province are hosted by subgreenschist to greenschist facies metasediments and show no spatial association with granitic rocks. They commonly parallel axial plane foliations or occur in brittle to brittle-ductile shear zones. Detailed mapping in the Hodgkinson goldfield indicates that vein systems are isolated in distinct structural and lithologic domains by post-mineralization faulting. Gold-quartz and antimony-gold-quartz veins have distinctive mesoscopic textures characteristic of the mesothermal vein environment. Some of the antimony-gold-quartz veins are located on domain boundaries which truncate the gold mineralization. In. some areas, tin and tungsten-tin mineralization which are spatially related to Late Palaeozoic granitoids appear to postdate the gold-quartz and antimony-gold-quartz mineralization.Oxygen and hydrogen isotopic studies of vein and alteration assemblages associated with these diverse ores provide constraints on fluid sources and have implications for the origin of mesothermal gold mineralization. The available isotopic data are consistent with a dominantly magmatic source for tin and tungsten-tin mineralization although there is evidence of a late-stage meteoric component in some tin-mineralizing systems. Although a distal magmatic contribution cannot be entirely discounted, the gold-quartz and antimony-gold-quartz veins were probably deposited from deeply

Jan 1, 1990

By Radmuller H

The proposed underground mine at Porgera forms an integral part of the Porgera Joint Venture project in Enga Province in the remote Highlands of Papua New Guinea. The total in-situ reserves are approaching 400 tonnes of gold making the Porgera deposit one of the largest in the world. The remote, rugged and inhospitable terrain, recent unstable geological environment and primitive yet socially complex nature of the densely populated local community, combine to make the Porgera project very different to developing mines in Australia. The Porgera project is a challenging and exciting mining exploration venture in the final stages of feasibility study submission and negotiations with the National Government of Papua New Guinea. A 1476 m exploration adit was driven in the footwall of the high grade mineralisation for diamond drilling purposes as part of the evaluations necessary for the feasibility study. Ground conditions encountered have ranged from weak mudstones with high water content, requiring immediate steel set support, to competent intrusives.

Jan 1, 1988

By Corrans I. J

A wide variety of copper-bearing gold ores exist throughout the world which have yet to be processed economically for gold recovery. The copper minerals present in these ores can be many and varied and usually result in high cyanide consumptions and problematical levels of copper in leach solutions. The copper content is often assessed as being of nuisance value as the ores are generally of the grade or type which can support neither a copper project nor a straight gold project, due to the interference of copper. Many of these problematical gold-copper ores could possibly be processed economically for gold recovery using a novel ammoniacal cyanide leaching system which utilises a copper-ammonia-cyanide complex as an effective lixiviant for gold, yet limits copper dissolution and conserves cyanide. Results from recent testing have promoted a re-evaluation of the economics of treating some gold-copper ores. This paper describes the novel leaching process and discusses the conditions employed to treat a variety of gold-copper ores.

Jan 1, 1992

By Ypma PJM

The Westmoreland uranium deposits occur on the northern flank of the Murphy Tectonic Ridge in the upper member of the Westmoreland Conglom- erate. Uranium mineralization is spatially associated with the contact of the overlying basaltic Siegal Volcanics and the margins of in- trusive dolerite dykes which are geochemically similar to the Siegal Volcanics. Thermoluminescence (TL) measurements on 800 samples from within the orebodies and surr- ounding host rock (up to 8 kilometres away from the deposits) have indicated that all of the Westmoreland Conglomerate has suffered major radiation damagg attributable to at least 10 ppm uranium over 10 years. The underlying rhyolitic Mid Proterozoic Cliffdale Volcanics have distinctive TL glow curves indicative of radiation sensitization caused by high uranium contents. These vol- canics are part of the Mid Proterozoic volcanic event known to be enriched in uranium. The Westmoreland Conglomerate has been derived by erosion of the uranium-rich Cliffdale Volcanics and associated Nicholson Granite Complex which makes it likely that the Westmoreland Conglom- erate had a high inherent uranium content.

Jan 1, 1984

Proceeding from statistical data on the development of waste volume, an endeavour was made to characterise waste materials with regard to the applicability of treatments based on mineral processing. Many types of waste are characterised by a high heterogeneity. The separation processes used for processing raw minerals can also be used for separation of various waste mixtures. For some waste mixtures, differences in properties can be utilised for separation which are mostly less distinctive for raw minerals. State-of-the-art technology is illustrated with selected Examples.

Jan 1, 1993