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The application of new and currently practised mining techniques in new areas and at greater depths necessitates considerable and immediate research effort. This effort is aimed at identifying the factors which make a particular method suitable and economically viable in a given geological, structural and operational environment. These factors, together with greatly enhanced knowledge of a deposit at the exploration and planning stage, allow selection of the most appropriate and efficient mining method in a new area such that coal resource recovery is maximised in a cost effective manner. Current research and future requirements for research into mining methods and associated equipment and mine services are reviewed.

Jan 1, 1981

By Carter J. P

A two year study into the effects of coal mining induced subsidence on cliff lines was undertaken by the Department of Mineral Resources with the support of a grant under the National Energy Research, Development and Demonstration Program. A new monitoring technique, using an Electronic Distance Meter and acrylic reflectors attached to the cliffs, provided safety for the surveyors and extensive and accurate three dimensional displacement data on the movement of the cliffs as they were being undermined. The study report included many graphs showing the measured vertical and horizontal displacements, differential subsidence, tilts and strains and included analysis of these movements with various parameters, such as, seam thickness, depth of cover and distances between the reflectors, longwall face and the edge of the chain pillar. Some of these graphs are presented in this paper and could be used, with caution, to predict subsidence movements around other cliff lines, after allowing for differences in geology and mining layout. A mechanism is suggested as an explanation for the observed high horizontal movements around the cliff lines. Sixteen percent of the overall lengths of cliffs that were undermined during the monitoring study fell and the contributions of various factors that appeared to influence the cliff falls are discussed. It is concluded that no single factor dominated as the major cause of the cliff falls and, often, many factors combined to cause cliff face instability.

Jan 1, 1992

By Griffith L, Lama RD

West Cliff Colliery mines Bulli Seam occurring at a depth of approximately 480 m. The Seam is intersected by a number of small shear zones and faults. While the faults have caused displacement of the seam, the shear zones are strike-slip structures with small apparent displacement of seam. Outbursts at West Cliff Colliery occur while driving through these shear zones. Few outburst wave occurred where faults have been intersected. In the last 3 years, over one hundred outbursts have occurred at West Cliff Colliery. The size of outbursts varies from a small bump to exceeding 140 tonnes of coal. A number of studies have been undertaken at West Cliff Colliery to control outbursts and predict Outbursts in advance of workings. These include: geological investigations, microseismic techniques, gas adsorption studies and gas drainage. The investigations to date suggest that outbursts of gas at West Cliff Colliery are more a gas phenomenon similar to what occurs in overseas mines. The results of various investigations are reported. West Cliff Colliery is located in the mid- west of the southern coal fields of N.S.W.

Jan 1, 1980

Despite the research interest on non-cyanide gold lixiviants over the past three decades all the non-cyanide gold processes are still at the developmental stages with limited understanding on solution and pulp chemistry in some cases. This is partly associated with:the difficulties in measuring reliable equilibrium data for various gold(I/III) complexes with non-cyanide ligands; the lack of knowledge on mixed-ligand complexes; and different kinetic stabilities of gold(I) complexes with respect to disproportionation. This paper presents reliable equilibrium data for complex formation, dissolution, precipitation, hydrolysis and disproportionation reactions of gold(I/III) compounds with a range of non-cyanide ligands: S2-, HS-, S2O32-, SO32-, SCN-, SC(NH2)2, OH-, NH3, Cl-. Solubility of gold(III) compounds with non-cyanide ligands follows the order: Cl- > NH3 > OH-. In the case of gold metal the solubility order at a given temperature is MgS > Fe(III) or Cu(II) / Cl- > Cu(II)/NH3 > NaOH, but the solubility increases with increasing temperature. Rate of gold oxidation with different non-cyanide lixiviants depends on the oxidant, ligand and temperature and follows the general order of oxidants: Fe(III) or Cu(II) > X2 or OX- > O2 (X = halogen). In the case of metal ion oxidants oxygen is required to reoxidise Cu(I) or Fe(II). Some of the reported data on chloride and thiosulfate leaching of gold are presented to highlight the effect of additives and the copper, silver and sulfur contents of the starting material on the success of non-cyanide leaching processes.

Jan 1, 2004

By M Wen, J Gerit, C A. Pelletier, D Muggli

On-land waste rock dumps at BHP Billiton Base MetalsÆ Island Copper Mine (ICM) near the northern end of Vancouver Island, B.C. continue to discharge ARD. These waters, which amount to approximately five million cubic metres each year, are injected into a three-layer, meromictic pit lake for treatment. The top layer is brackish water, replenished by each yearÆs rainfall (amounting to nearly 2 m/year). This top layer of water must meet effluent permit limits for heavy metals. This water eventually exfiltrates through a æbeachÆ waste rock dump, which is 93 per cent submerged along the north shore of Rupert Inlet. The middle and bottom layers of the Pit Lake are saline and currently oxic (2 mg/L dissolved oxygen) and anoxic (0.03 mg/L dissolved oxygen), respectively. Spreading of a liquid fertilizer every ten days throughout the top layer results in plankton and bacterial blooms that scavenge zinc, copper and cadmium out of this layer eventually to become mineral sediment in the bottom of the pit lake. Adsorption on planktonic skeletons and mineral precipitates also scavenges these dissolved metals from the middle and bottom layers to form bottom sediment. Sulfate reduction has recently begun in the bottom sediments. Diagenetic processes in the bottom sediments will eventually transform most of the dissolved heavy metals into insoluble sulfides. Cycling of ferric iron between the sediment and the water column and back seems to contribute dramatically to the biogeochemical metal removal processes. This biogeochemical system serves to maintain the top-layer water well within permit limits for discharge to the environment.

Jan 1, 2003

The Lower Proterozoic metasediments of the Pine Creek Geosyncline form a chrono- stratigraphic sequence of mainly greenschist- and amphibolite-grade shallow-marine to supratidal pelites, psammites, carbonate rocks, and volcaniclastics which in places rests unconformably on Archaean basement. Granite and later dolerite intrude the sequence, and are associated with the major orogenic 1800-m.y. event which regionally metamorphosed the sediments. Most mineralisation is stratabound, and can be related at least partly to volcanic activity. Uranium mineralisation is mainly confined to particular carbonate-rich horizons near basement. Other metals are mainly in small hydrothermal deposits near intrusive granite. Specialist studies indicate that uranium was leached from its source rock, and probably carried as carbonate complexes in highly saline fluids at between 100 and 3500 C. Precipitation took place by redox reactions in breccia zones in carbonate rocks; these zones were formed by carbonate solution or diapiric movement of evaporites which preceded the carbonate. Extensive chloritisation in the ore zones suggests metasomatism by Fe- and Mg-rich fluids which may have evolved during dewatering of the evaporites. The main mineralising event took place after the 1800 m.y. metamorphism, and was probably

Jan 1, 1979

From depths of 400 - 600 m, coal is transported by a conveyor in a drift or a bulk winder in a shaft, whilst men and/or materials are transported by a slope hauler or a cage winder. Assessment of the effect of alternative combinations on the key cost factors - output, capital, labour cost and construction time - allows the optimum choice for particular circumstances, there being no uniform solution.

Jan 1, 1976

By Thompson AG, Cadby GW

The New Austrian Tunnelling Method (NATM) is a proven concept for the safe and economic construction of underground facilities. This is especially true for tunnelling activity where changing ground conditions are often encountered. However, the principles central to the NATM have gained only limited use within Australia, presumably due to the measurement process inter- fering with tunnel driving and the cost associated with instrumentation and interpre- tation expertise. The design and operating principles of two basic instruments are explained together with laboratory simulated test results and suggest- ions for use in an integrated NATM style approach to underground excavation and construc- tion. The two instruments monitor load in rock reinforcement and deformation in rock or primary and secondary linings. The instruments may be fitted with a miniature display module which outputs the measured parameter in engineering units directly. The design of the sensing components allows the instruments to be installed in various configurations suitable for routine performance monitoring, quality control, support element testing or detailed investigations. The display module which reduces the need for instrumenta- tion expertise should suit contractors and allow performance data to be obtained which quickly may be used to modify support procedures to suit ground conditions. When complemented by convergence measurements the devices enable most facets of the NATM to be implemented.

Jan 1, 1987

By Braaksma M, Dudley K

The Girilambone Copper Mine is located in central New South Wales and has been operational since May 1993. Girilambone is operated by the Girilambone Copper Company (GCC) which is a joint venture between Straits Resources (60 per cent) and Nord Resources (40 per cent). The mine complex consists of an open cut pit, ore crushing and stacking, heap leaching, solvent extraction (SX) and electrowinning (EW) allowing for the recovery of 14 600 tpa of LME grade A cathode copper. The leaching and SX-EW plant have been described previously by Rear, Taylor and Busby (1994) and Miller (1994).

Jan 1, 1996

The planned extraction of deeper copper ore at Isa Mine has necessitated a review of existing equipment and methods to contain costs and improve working conditions. Mining is in progress for a crushing-conveying system to serve the deeper southern areas of the 1100 Orebody. This system will permit direct tipping of ore to the crushers and conveying of the crushed ore by cable belt conveyor to existing shaft loading facilities, a distance of about 2 km. To develop part of the conveyor drive a new machine will be used, the Robbins MM120 Mobile Miner, a joint development project between The Robbins Company and Mount Isa Mines Limited. The Mobile Miner uses a rotating cutting wheel to excavate headings 3.7 m high and from 4.7 m to 7.5 m wide. To ventilate the deep crusher complexes and associated development at high virgin rock temperatures, a refrigeration plant will be built on surface to reticulate chilled water underground. Bulk cooling of air to the 3000/3500 Orebodies and the southern crushers will be combined with the reticulation of chilled service water to the lower workings of the mine.

Jan 1, 1984

By Martin C. H, Met B

INDEX OF CONTENTS:1. Introduction, Explanatory; and Reasons for Coal Cleaning.2. Principles on which Coal Cleaning is based.3. Location of Broken Hill Proprietary Co. Ltd. Plant.4. Description of Processes Selected Barvoys Bath Process; Barvoys Medium Preparation and Treatment; Static Dry Cleaning Plant.5. Detailed Description of Plant.6. Typical Results of Cleaning Operations.INTRODUCTION, EXPLANATORY, AND REASONS FOR COALCLEANING:The Institute proceedings have not previously published any matter on coal cleaning and the reasons thereof; in consequence it has been deemed advisable to allot a part of this paper to explanatory matter, prior to entering into a detailed explanation and description of the Newcastle plant.At the outset it would be as well to consider briefly the kinds of materials from which coal has originated. All coals represent some stage in the decomposition and transformation of vegetable matter laid down in prehistoric times, the vegetable matter undergoing numerous geological changes, such as submergence, overlaying by sediment, with subsequent pressure and re-elevation; these processes may...

Jan 1, 1946

By Wilson R. G

The Bulli and Wongawilli Seams, the two principal sources of coking coal for the Port KKembla steelworks of Australian Iron and Steel Pty. Ltd., vary in rank and in type over the Southern and -South Western Coalfields. The Bulli Seam, ranging widely in type, produces coke varying from weak to strong. The Wongawilli Seam, more consistent in type, produces coke of more consistent strength, but considerably less strong than that from the best Bulli Seam coal. Plans of seam variation show the regional trends in rank and type for each sear. The strongest coke is derived from coal containing between 45 and 55 per cent vitrinite, m.m.f. This is obtainable from the Bulli Sean in a zone embracing Bulli and Appin Colleries.

Jan 1, 1969

A form of wet pelletization is described where the bridging of the individual particles is achieved by a second liquid phase that pref- erentially wets the suspended solid particles. The phenomenon can be used to obtain efficient separation of solids from carrier liquids, to form spheres from finely divided solid materials, and to separate selected constituents from a body of mixed solids. Typical examples of each of these applications are presented.

Jan 1, 1974

By Propster M, Choudhry M

THIS note gives comments on the paper by Kitaev et al on p. 68 of this book and compares results with those obtained by ourselves. We wish to say that the authors are to be congratulated on their sophisticated approach to an important problem and that it complements our efforts on flow maldistribution.1-5 It is our view that Eqs. (1)-(5) on p. 69 are impressive, but unfortunately with present day computers and computational facilities, it would be quite impractical to contemplate the numerical solution of these. Eq. (8) in the authors' paper, on p. 70, does provide the logical starting point for tackling flow maldistribution problems and strictly speaking this equation is more accurate than Eq. (1) in our paper in this book. We note in passing that there is direct experimental evidence to support the contention that our Eq. (1) is at least a reasonable approximation and one may question in a practical sense whether the refinement afforded by Eq. (8) in the paper by Kitaev et a/ is justified. While one must readily accept the appropriateness of Eq. (8) of Kitaev et al as a starting point, the subsequent mathematical manipulation by the authors is open to serious criticism. In order to solve this complex, non-linear equation Kitaev et al postulated irrotational flow, which afforded considerable simplification. One can argue simply on physical grounds that the assumption of irrotational flow is inappropriate, a fact which should be readily apparent on inspection of the flow fields shown in Figs. 2 and 3 of Kitaev's paper. It follows that while the starting point through the use of Eq. (8) is correct the results derived from this starting point may be suspect because of the erroneous nature of the irrotational flow assumption.

Jan 1, 1975

Carbonate-hosted massive sulfide ores of the American cordillera compose a distinctive genetic class. Discordant fea-tures of occurrence together with measured high-temperatures of formation indicate their essential epigenetic character and close spatial association with centers of thermal activity during evolution of the cordillera. Their metallogenic character is complex from region to region: Cu-Zn-Pb-Ag, Pb-Zn-Ag, and Cu-Zn-Ag-Au represent extremes of composition and each may be identified with specific terranes of occurrence, notwithstand-ing an inferred common process of formation. Beyond the presence of a thermal center, other controls that may be identi-fied include apparent but obscure properties of primary perme-ability or chemistry of hosting strata, and secondary controls are imposed by stratigraphic differences in which permeability is strongly contrasted. Structures that act as channelways may be identified in some instances. Notwithstanding their intrinsic value, search for these ores is difficult and requires the solution of complex geochemical and three-dimensional geometric problems.

Jan 1, 1990

By Marshall B, Gee R. D

Geological data processing by machine enables'an increased rate of coverage, better supervision and control of field programmes, increased effectiveness of field operators, and vastly improved access to old and new field data. Even a system of restricted felxibility enables a mapping programme to be organ- ized and conducted independent of personnel changes, whilst elimination of much compilation time increases the rate of cover- age such that it relates to mode of transport and geological complexity rather than to personality factors. A machine is useful only if applied to tasks suited to its capabilities, and must be aimed at those types of mapping in which a limited number of attributes adequately define the problem, and the data is of a form suited to coding and is normally collected in sufficient abundance to make compilation wearisome. Machine systems are therefore unsuited to most types of lithological mapping and to most types of exploration in new areas, but have proved useful in many branched of cartographic geophysics (e.g. gravity and magnetics), and in cartographic Geochemistry.

Jan 1, 1969

By Mathew P. J

The CSIRO Division of Mineral and Process Engineering in Melbourne has been developing on-stream analysis sensors based on neutron and gamma radiation for better control of quality and process operations. This has resulted in the development of Ironscan, an on-stream analyser that measures the iron content of both lump and fine iron ore on conveyor belts. It can be mounted under existing conveyors with minimal modifications to the conveyor structure and can cope with steel cables in the belt. An interface gauge and an on-stream coal ash analyser have also been developed, both based on measurement of natural radioactivity. The interface gauge monitors the interface between liquor and mud in thickeners and washers, provided the natural radioactivity of the mud is sufficiently high to detect it above background. The natural-gamma ash gauge is a valuable addition to the Coalscan range of ash gauges. It is applicable to heavily laden coal conveyors or bins where the coal bed thickness exceeds 30 cm, and also to lightly laden conveyors, provided the coal is profiled on the conveyor.

Jan 1, 1991

By Kelley BC, Filmer AO

The chemical oxidation kinetics of sphalerite by Fe(III) was studied at various temperatures and size fractions in sulphate media. The kinetics of Zn extraction followed a pore diffusion control mechanism with an apparent activation energy of 54-58 kJ mole. This figure, although high for a pore diffusion control process, is consistent with other studies carried out in sulphate media. An empirical statistical model, relating the extraction time to % Zn extraction, average particle size and temperature, is described by log 1 = 12.22 - 0.017% Ext. - 1.76 log D Av t - 2954 T Parallel studies were also carried out investigating the biological oxidation of sphalerite utilizing the acidophilic autotrophic bacterium Thiobacillus Ferroxidans. The effect of such kinetic parameters as pulp density, particle size and Fe(III) on bacterial growth rate and consequently zinc extraction rate, were studied and where appropriate, optimum conditions for bacterial growth were specified. Based on the results of chemical and biological leaching studies, it was apparent that rapid zinc extraction from sphalerite was predominently due to oxidation by Fe(III). The biological oxidation process catalyses the oxidation and regeneration of Fe(III). The proposed combined chemical-biological leach system was simulated in semi continuous fashion. The sphalerite oxidation rates obtained in this system were similar to that predicted by the chemical leach empirical model. 1. Senior Research Metallurgist, CRA Research, Boolaroo, N.S.W. 2. Group Leader-Hydrometallurgy, CRA Research, Boolaroo, N.S.W. 3. Senior Research Scientist, Biotechnology Australia, Roseville, N.S.W. 4. Senior Experimental Officer, Biotechnology Australia, Roseville, N.S.W.

Jan 1, 1986

By R Schlueter, H Mischo

The mining industry is facing a variety of geological, technological and social challenges. Future deposits show a general tendency towards increasing depth with complex ores and decreasing grades. One promising approach to deal with low-grade ores is bioleaching in the form of heap and dump operations. Bioleaching is already a state-of-the-art technique, especially for the extraction of copper from sulfide ores. The next step in the development of this technology will be its application as an in situ technology. First attempts to adapt this technology in underground mining in the form of stoping and block caving have already been made. Both methods have to be carried out adjacent to conventional mining operations and therefore require much effort regarding drift development as well as extraction and transport. The adaption of bioleaching as a borehole mining method is the next step to establish an innovative in situ technique to meet future challenges.The Freiberg University of Mining and Technology established the Biohydrometallurgical Centre for Strategic Elements (BHMZ) to foster interdisciplinary research along the whole biohydrometallurgical process chain. In general, 13 different university institutes and several associated groups with about 30 PhD students are mainly focusing on the extraction of indium and germanium from deposits, tailings and recycling material. One of the core projects within the BHMZ is the design and implementation of an underground in situ bioleaching testing facility.This paper demonstrates the potential of in situ bioleaching under technological aspects. Furthermore, different conditioning methods to increase the permeability of the orebody will be explained, and the BHMZ’s underground testing facility will be presented.CITATION:Schlueter, R and Mischo, H, 2015. Potential and applications of underground in situ bioleaching, in Proceedings Third International Future Mining Conference, pp 205–212 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

This paper briefly discusses the negotia- tion of the more important provisions in agree- ments for exploration and mining rights with Pacific countries. LAND RIGHTS Land rights are complicated and sometimes controversial in many of the Pacific countries. In some countries, a company will have to deal with land owners directly; in others, the government will act as intermediary. Inevit- ably, a company will have to deal with both. Mining companies need to be sensitive to the culture and particular interests of the land owners and of their history in defending their rights. The issues are too complicated to be dealt with here. Some mining companies have spent, and will continue to spend, considerable time trying to understand them. It will " require patience, perseverance, sensitivity and unflagging optimism. The better advised companies will ensure that their local repre- sentatives get to know the land owners, under- stand their concerns, and will pursue a policy of keeping them informed on a regular basis of all of the company's activities and proposed activities. Good community relations are the keystone for good mining operations in the Pacific. Most countries will require the submission of an environmental impact statement so that they will know in advance what effects a pro- posted mining operation are expected to have on the environment and how it is intended to deal with them. They will also want to approve the company's environmental reclamation and rehabilitation plan. Let's face facts right away - mining, by its very nature, is not going to improve the environment. There will be waste discharges, emissions and deposits. They will affect the land, air and water and hence human, marine and animal life and vegetation. There will be sounds and odours and the esthetics of mining operations, though perhaps pleasing to geolo- gists and mining engineers, will not please Others.

Jan 1, 1987