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Australia, with its fast-growing economy and high standard of a~ living, has a high and rapidly increasing per capita consumption of energyIn total terms, Australia's energy requirements are doubling every 15 years, and among mature Western economies Australia ranks behind only Italy-and Japan in the rate of increase of energy consumption.The use of energy is often accepted as a yardstick of development and on this basis Australia might well congratulate itself on its high energy consumption. However, it is less well recognised that the resources absorbed in the production of energy represent a real cost to the* community, and that just as we strive for industrial efficiency or farm productivity we should strive for economy in the use of energy fuels.Australians spend annually an estimated ú500 million.on all forms of energy, a sum which represents about seven per cent of the Gross National Product. In all, energy production and distribution absorb the employment of more than 100,000 persons. In addition, the annual capital investment by.the oil industry amounts to some E55 millions, by the coal industry about ú12 millions, and by electrical and gas authorities some E108 millions, in total representing more than ten per cent of annual investment in other than private motor cars and housing,

Jan 1, 1962

The proportion of coal production from underground operations in Queensland, is likely to increase in the future. A portion of this increase will come from mines working under farming areas. The degree of compatibility between underground coal mining operations and farming is examined. Two case histories are considered in detail. These relate to farming areas in the Moura and Emerald districts. Mining the Moura, area has been undertaken for the last two and half decades, while in the Emerald area, large scale underground coal mining is currently being planned. Interference to watercourses and water harvesting programmes, damage to crops, and ponding in cultivated areas have been experienced in mining areas. With expansion of underground mining in farming areas, the principle areas of likely conflict are the effects of surface subsidence on irrigation and erosion control structures. Other potential problems that may arise in particular circumstances include reduction in availability of water for harvesting, pollution, surface cracking and damage to surface structures. Finely textured soils and erratic and violent rainfall patterns make farming in central Queensland particularly vulnerable to severe soil erosion unless strict precautions are taken. Soil erosion control is an essential part of farming. Contour banks are used to ensure that runoff velocities are suitably low. Where steep slopes are encountered, grassing is the most effective way to prevent erosion.

Jan 1, 1987

By S Wasi, J Tobiczyk, J Roszkowski

Methane and fire hazards have a vital effect on work safety and continuity of mining plant operation. In the 1990s, the SMP hazards monitoring and ventilation control systems, based on continuous measurement of air parameters, were put into operation at nearly 30 Polish mines. These systems provide continuous measurement of methane concentration within the range of zero to 100 per cent with automatic switching off of electrical energy immediately after detection of potentially explosive conditions. Early detection of coal spontaneous combustion and open fires is made by continuous measurements of CO, CO2, smoke and O2 content in mine air as well as temperature changes in air and rock mass. The essence of the system is intrinsic safety of all underground instrumentation and uninterrupted central power supply from the surface. All abnormal and critical states are signalled to the mine control room. These trigger alarm and emergency procedures. The computer based ventilation monitoring and control system also performs the function of an expert system for fire detection and underground fire fighting. The mine control operator (dispatcher) makes use of stored data in computer escape route schemes and procedures for the safe withdrawal of miners from hazardous areas. The operator can put in motion intrinsically safe alarm signalling units and banners with programmed messages indicating escape routes.

Jan 1, 2005

After the minim operation, most raw materials that occur in the earth's crust require some form of processing or refining before they can be converted into a final end product. In the mineral industry these remarks apply to materials such as iron ore, bauxite, limestone, copper ore and many others that are found in Australia in large quantities. Processing plants for these raw materials operate more efficiently, however, if the feed to them is consistent in both physical and chemical characteristics. Such uniformity rarely occurs in nature so that some form of homogenisation, or blending, is required ahead of the processing plant. Bending also assists the mining operation itself by reducing; the need for selective mining and, by combining high and low grade materials, a more uniformly graded, commercially acceptable product can be obtained, thereby increasing the commercial life of a mine or quarry. Bed blending is the most efficient of the processes available, and following its development in the United States in 1905, over 100 plants have been installed, or are under construction, all over the world. The original process, the Robins--Nessiter system, has been the subject of continued improvements and refinements, so that economical capacities are possible from less than 100 l.t.p.h. up to 10,000 l.t.p,h. and beyond.

Jan 1, 1969

By S Youds

The backfilling operation at Olympic Dam mine supports a 9.8 Mtpa underground Long Hole Open Stoping (LHOS) operation. It involves a combination of Cemented Aggregate Fill (CAF), surface rockfill and underground rockfill. The fill material is introduced from the surface via boreholes into the top of the stopes. Due to the deleterious effects of the dust and the thickness of the atmosphere in the stope it is not possible to view the filling process either at optical or infrared (IR) wavelengths. The need for a means to measure the filling process is driven by the placement of both rock and CAF fill in the stopes. The large volumes and high relative cost of CAF makes the minimisation of CAF fill a business priority. Incorrect filling can lead to the sterilisation of ore reserve. The use of millimeter wave radar to view through the haze to give real-time data on the relative positions of the different fill masses is being developed as an in-stope fill monitoring device. This paper reviews the salient points of the technology and its potential use in the backfilling operation at Olympic Dam. The broader potential of this technology for use in the mining industry by æseeingÆ through water and dust laden environments such as that found in stopes and ore passes is also discussed.

Jan 1, 2002

By Young D. R, Webb I. D

The hydro-chlorination of Fe2O3 and Fe304 has been investigated in the range 850-950¦C in order to elucidate the role of iron in the segregation process for nickeliferous laterites. The kinetics of Fe203 chlorination using 20% HC1 - 80% N2 gas mixtures is consistent with a single-stage structure control model, whereas Fe3O 4 exhibits a two-stage reaction mechanism. Oxygen potential measurements using a CSZ probe located above the bed and X-ray powder diffraction results confirm the proposed reaction scheme. When a serpentine nickeliferous laterite (1.03% Ni - 11.7% Fe) was chlorinated at 900¦C with a 20% HCl - 80% N2 gas mixture it was found that the iron oxide in the ore was extracted in a similar manner to the synthetic iron oxides. Also, it was found that the nickel extraction from the ore paralleled that of the iron and the tests indicated that for the major part of the extraction, the solid nickel species were in equilibrium with the gas phase. The recovery of nickel from laterite ores by the segregation process has been investigated by a number of workers and several extensive reviews of the literature associated with this field have been published (Iwasaki, 1972; Canterford, 1975; Wright, 1973).

Jan 1, 1987

The distribution of p(~rphyt1 copper deposits, in time as well as place, is used to propose an occurrence model based on the genesis models of Sillitoe and Rona. A magmatic source of the metals is accepted. The characteristic metallogenic epoch and the migration of the mineralization event along an elongate metal province are explained as the result of subduction of an obliquely- oriented strip of mineral-enriched material on the oceanic plate. Two mineral-enriched trails emanate from a hot-spot source of high-intensity hydrothermal activity in an oceanic rift. Because the whole plate system moves relative to hot spots, the hydrothermal source appears to migrate along the rift, and the two trails are not parallel to transform faults, but form a broad "V" centred on the hotspot. Source loci are spaced at intervals of about 3000 km, resulting in the possible repetition of metallogenic epochs, in a subduction zone province, at about 100 m.y. intervals. The position of the mineral-enriched strip can be found graphically, given ages of a series of deposits in a province, and the plate convergence vectors. This knowledge provides an exploration tool at regional scale and, by reflection across the rift, the potential for exploration is extended across oceans. The model has implications for commodities and deposit types other than porphyry coppers.

Jan 1, 1987

By Okura T, Hino J

Coal utilization for copper flash smelting in Japan was initiated due to the sudden upheaval in the price of oil in the last ten years. A major portion of the heavy fuel oil has already been replaced by coal resulting in a corresponding decrease in energy costs. In addition to energy cost savings, an interesting metallurgical phenomenon was observed in flash smelting operations. Unlike oil combustion, coal is not burned completely in the shaft. A considerable fraction of coal particles remain on the surface of slag and are burned at the settler. Chemical investigation has shown that oxygen potentials at the settler have consequently decreased, bringing the slag and matte phases into reducing conditions, thus oxidation and reduction can coexist in one flash smelting unit. As a result, a decrease in magnetite and copper contents in the slag, elimination of furnace hearth build-up and dissolution of intermediate layer between matte and slag have been observed. In general, these led to improvements of furnace operations. However, thermodynamic investigations have shown that some minor elements such as As, Sb, Bi and Pb concentrate from slag to matte. Results evaluated on the basis of thermodynamic data relatively agree with practical observa- tions. Consequently, for coal utilization in flash smelting operations it will be necessary to control oxygen potentials from the stand- points of copper loss in slag and minor element Distributions.

Jan 1, 1987

THE power requirements of the Mount Lyell Mining and Railway Company at Queenstown, Tasmania, have, since the inception of smelting operations in June, 1,,896, been derived continuously from the extensive forests in the watershed of the Queen River, adjacent to -the works, the firewood being of good quality, mainly composed of myrtle or beech (Fagus Ounninghami), eucalypts, and manuka (Leptospermum ericoides).The country is very rugged and mountainous, indented by numerous ravines and gullies, and intersected by many creeks, which are subject to periodical floods, under the influence of a heavy and persistent rainfall. The areas so far exploited aggregate a total of about 42 sq. 'miles, and this denuded country gives promise of ultimately becoming very valuable pastoral ground for cattle-raising. The tonnage of wood yielded per acre varies from 40 to 100 tons on stack measurement of 80 cub. ft. per ton, 60 tons per acre being considered a good average yield. The gross amount of firewood handled during the past 13 years approximates 1,200,000 tons, the greater portion of which has been obtained by ordinary tramming methods. The company's main line of railway, 3-ft. 6-in. gauge, has served as a trunk line for all supplies derived from the Queen River valley, south of the reduction works, while the northern and western areas have been exploited by means of...

Jan 1, 1911

By Brinkmann J. R

The relative effects of the two basic mechanisms contributing to rock breakage during blasting, shock and gas penetration, are neither well understood nor well characterized, and need further clarification. Blasthole liner (BHL) tests separate the two effects, and by enabling direct measurement of borehole expansion give insight into the shock/gas energy partitioning in rock confinement. The hydrodynamic code DYNA2D is used to simulate the shock effect of the detonation of emulsion in a stainless steel lined hole, and the predicted expansion is compared with experiment. Workers in the past have neglected near-blasthole phenomena and have calibrated models based on stress measurements remote from the blasthole. Extrapolation back to the blasthole has inherent limitations, and indeed, one of the deficiencies of these models is that they have not been able to predict correct borehole expansions, as observed in BHL experiments. DYNA2D has been enhanced by the ICI group with a detonation model which resolves the explosive reaction zone. As a preliminary step towards the ultimate goal of devising a practical damage model, simulations are used to predict the maximum expansion that would take place if the rock were to remain undamaged. Various material parameters are investigated and it is shown that calculated liner expansions are appreciably lower than measured values for high rock yield strengths, while greater than values for low yield strengths.

Jan 1, 1990

A laminar-flow furnace technique was used to study the combustion of 37-53 µm size fraction of Woodlawn copper concentrate containing 7.4 per cent zinc, 5.0 per cent lead and 22.5 per cent copper. Factors studied included the effect of time, temperature and the distribution of volatile elements between the panicles and the fume. Air was used for most of the work but a few tests were carried out using 1 per cent oxygen in nitrogen. Chemical analysis, X-ray diffraction, and scanning electron and optical microscopy of polished sections were used to characterize the reaction products.When the concentrate was combusted at low temperatures (800-900°C), the fume was rich in lead. At higher temperatures, this was diluled by increasing amounts of zinc and copper. 70 per cent of the zinc, 60 per cent of the lead and 40 per cent of the copper were found in the fume after oxidation at 1400°C. Lead, zinc and copper were present in the fume as anglesite (PbSO4), zincite (ZnO) and cuprite (Cu2O) respectively. The major phases present in the panicles were magnetite (Fe3O4) and/or cuprospinel (CuFe2O4), with some zincite and cuprite.Elemental copper was found in the particles oxidized in 1 per cent oxygen. Possible vapour species responsible for the vaporization are discussed.

Jan 1, 1985

Underground measurements, observations and computed simulations, started a long time ago were concerning the study of : - occurence of typical rockburst, - inducing, stretching of main fractures in the roof of caved longwalls. They made obvious a foundamental phenomenon of inducing of strata fractures involving contact be- tween two layers quite different in their elastic characteristics : coalseam and rocklayer.. The start of primary cracks in maximum abutment zone takes place in the rock near the contact surface. It is opening of crevasses induced by traction stress component resulting of difference of rigidity of both materials and no sliding on in- terface. Occurence and stretching of these crevas- ses are a rheological phenomenon so that the rate of advance and stops of the face influence the distance between the crevasses and the stretching of these ones. The characteristics of these cracks in space and time affect mining conditions. So it is for fractures proximity and expan- sion inducing eventual blocks formation in longwall roofs in front of faces, for depth and delay of road- ways ribsides fracturing, inducing some rockbursts. In longwalls roofs, cracks initiated in front of a face can be either quite close or quite distant each from the other one, according to the depth of crushed coal in front of the face, which af- fects also extension of the cracks.

Jan 1, 1988

Vatukoula is credited with the second largest population in the Colony of Fiji. Within an area comprising 550 acres are living approximately 4,500 people. Of these, about 1,150 Fijians, 90 Rotumans, 90 Europeans, 180 Part-Europeans, 180 Indians and 30 Chinese and miscellaneous Pacific islanders are employees of the Associated Mining Companies.The remainder is made up of employees dependants with a small minority of tradespeople and Government servants, such as storekeepers, school teachers, police and post office officials.To appreciate fully the work involved in the administration of this unusual community it is necessary firstly to know something about the various types of people which compose it.The FijiansAlthough the Fijians are of Melanesian stock their physical characteristics indicate a Polynesian strain. Natives from all provinces in the Colony are to be found in Vatukoula and their varied types point to this MelanesianPolynesian intermixture. For example, there are people from Lau** and Kadavu who are tall and well built with good features and comparatively fair skins contrasting with the dark, broad featured and generally short people of the hill tribes of Ra and the coastal tribes of Bua.The Fijians, particularly the older people, are noted for their dignity, courtesy and hospitality. The young Fijians of the present generation, large numbers of whom are...

Jan 1, 1953

By J Hadjigeorgiou

The stability of open stopes in underground hard rock mines is influenced by several factors including the shape and size of the excavation, surrounding stresses as well as the degree of jointing. This paper presents a design methodology for stope analysis in jointed rock masses. The proposed approach relies on geological structural data to construct realistic three-dimensional joint network models. The stability of an open stope is determined based on a limit equilibrium analysis.

Jan 1, 2000

The economic valuation of mineral prospects usually involves DCF analysis of expected revenues and costs. Traditional approaches deal with price uncertainty by considering different price scenarios and may even consider cases where prices drop sufficiently for production to be suspended temporarily. This paper outlines recent extensions to the methodology derived from finance theory. We present a simple analytical model that focuses on the value of operational flexibility where future prices are uncertain.

Jan 1, 1988

By Schulz R. S, Staunton W. P, McGuire J

The increased activity in the Australian gold industry over the last decade has resulted in a concomitant increase in the use of sodium cyanide, with a projected consumption of 80,000 tonnes per annum by 1991. Growing environmental awareness by government, industry and the public has generated increased interest in the fate of cyanide near gold mine tailings dams and has highlighted the lack of basic knowledge in this area, particularly for Australian conditions.

Jan 1, 1991

It is argued that the capture of par- ticles by bubbles is primarily caused by hydrophobic ("structural") attraction forces. Neither dispersion forces nor double-layer forces can account for hydro- phobicity, though the latter are known to influence the kinetics of capture. The recent experiments of Israelachvili and Pashley (Nature, 300: 341-342, 1982) with hydrophobic mica plates provide the first measurements of the range and magni- tude of hydrophobic interaction forces.

Jan 1, 1984

Evaluation of tyre chains has been taking place at King Island Scheelite for several years. Results indicate that tyre life has been greatly improved in all cases. Good cost sav- ings are resulting on small loaders. The worth of chains is difficult to prove on larger loaders under the conditions at King Island Scheelite. However, the dramatic decrease in the number of punctures has convinced the Company that chains are worthwhile on some larger loaders.

Jan 1, 1977

A computer programming language known as GPSS is described and possible applications for the mining engineer are presented. The language is continually being upgraded with improved versions appearing about every three years. The tremendous power of the language is considered by comparing it with standard engineering programming languages, such as Fortran or Basic. Sample problems that can be solved using the language are indicated. The advantages and disadvantages of the languages are also discussed.

Jan 1, 1987

The title of my address today is "Oil and Gas Valuations - A Simplistic View of Some Critical Issues". Alternatively I could have called this address "Pitfalls for investors' and corporates in accessing Independent Experts Reports" 'as in this brief 12 minute talk I will briefly comment on some common misconceptions with regard to the valuation of exploration areas and production interests, and comment on how the draft release guidelines address these issues.

Jan 1, 1989