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By Buisman C. J N, Koch R. O

Soil and groundwater beneath the Budelco zinc production plant at Budel-Dorplein (The Netherlands) are contaminated with metals and sulphate. To avoid contamination of nearby drinking water aquifers in the very distant future, a geohydrological containment system (GCS) and a microbial treatment plant for extracted contaminated groundwater have been developed. As a first step in the design of the system groundwater data from over 150 wells and geological profiles were used to model geohydrological conditions beneath the site. Several configurations of water-extraction wells were deduced from the model. Data gathered during additional fieldwork were then used to improve the model. Finally results that were calculated for the various configurations were used to select an optimal groundwater containment system. Currently some 5000 m3/day groundwater are extracted from a combination of 12 shallow and deep wells. Heavy metals and sulphate have to be removed from the extracted water before it can be discharged into the river system or used as process water. Several water treatment methods have been studied and pilot-tested at the site. The preferred and selected process is based on the activity of sulphate reducing bacteria (SRB) and combines sulphate removal and heavy metal removal in one single step. The anaerobic bacteria reduce the sulphate to sulphide resulting in the precipitation of metal sulphides. A pilot plant gave promising results and a commercial-scale plant has been designed. The proposed design has been tested in a demonstration plant which included all main process units. Test results for all process units are presented. The collected information was then used to optimise the design of the commercial-scale plant. Special attention was paid to automation and safety items. Construction of the plant was finished in May 1992. Start-up, commissioning and operational experience are reported. The concentrations of metals and sulphate in the effluent of the SRB water treatment plant are well within the limits set by the authorities for discharge to public waters.

Jan 1, 1993

By Thirnbeck M, Sione T, Petrie P, Leach TM, Mori W, Digan K, Harry K

Gold and lesser copper mineralisation are associated with porphyry-related vein systems periph-eral to two separate inferred intrusive centres north of Kainantu, Papua New Guinea (PNG). The intersection of NW trending structures, formed parallel to the Markham Fault, with NE trending transfer structures localise porphyry intrusions, and control vein distrib-ution.The Arakompa veins intrude pre-existing fractures in Akuna granodiorite, located proximal to an inferred porphyry. These veins are characterised by early quartz and later pyrite-chalcopyrite. Gold mineralis-ation is associated with Bi-Te phases in the sulphide veining. At Maniape, en echelon gash veins occur within the imbricate portion of a regional structure. Maniape is a high level carbonate-base metal gold system formed distal to the same porphyry source as Z ?-;4 kmmna

Jan 1, 1994

By N Khalili, J Zhao, G F. Zhao

Toppling failure of a jointed rock slope was studied by using the distinct lattice spring model (DLSM). Compared with the classical discrete element model, the DLSM has the advantages of free calibration of micro-mechanical parameters and easy to represent discontinuities, and is more computationally efficient. In this work, the DLSM was used to investigate the toppling failure of jointed rock slopes. The numerical simulation was verified against experimental data from a centrifuge model test on a jointed rock slope. Both the horizontal deformations and failure pattern observed in the centrifuge test were reasonably reproduced using the DLSM. Then, the mechanism of the flexural toppling failure was studied numerically by using a parameter analysis. Finally, some insights were derived that may be useful for practical engineering.CITATION:Zhao, G F, Khalili, N and Zhao, J, 2014. Application of the distinct lattice spring model on toppling failure of a jointed rock slope, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 207–214 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By Harvey T, Kizil M, Bride J

Hydrogen sulphide (H2S) as a seam gas has occurred in several locations in the German Creek seam at Southern Colliery. This paper overviews the techniques developed to quantify the H2S content of the seam, overviews research into controlling and reducing H2S emissions from the seam, and details the procedures used to mine through the HZS zone in 702 longwall panel. Learning points from research and mining experience are reviewed for application in the next longwall block.

Jan 1, 1998

Most text books on rock blasting claim that the relationship between burden and borehole diameter is linear. The statistical calculation presented here with real values from one hundred open pit and underground mines indicates that the relationship is exponential. For underground mines the burdens are consistently lower than those for open pit mines because of higher ore densities, greater confinement in blasting, and finally greater demand for well fragmented rock. The results shown in this paper are recommended to be considered in basic teaching of rock blasting technique. The formulas can be used for a first rough estimation of practical burden and spacing. The formulas do not however give any information about the fragmentation. For that purpose it is necessary to use other formulas not described in this paper.

Jan 1, 1990

By Kato Y

As a direct result of the Mining Industries need to improve efficiency and production in Open Pit type operations, the size of haulage units have increased dramatically. This trend has continued such, that the majority of dump trucks operating in Open Pit operations are in the 170 ton class. Continued mining in existing locations has meant that the increase in vertical lift and resultant grades, and increases in hauling distances are making electric drive systems unsuitable. This is largely due to the electric drive systems heat limitations on major propulsion components. With these mining requirements in view and the present limitations on electric drive systems in mind, Komatsu have been developing the Komatsu HD1600M. A diesel powered mechanical drive dump truck capable of operating in deep pit operations. This presentation introduces: Komatsu HD1600M Dump Truck

Jan 1, 1982

The discovery of copper and nickel sulphides in the Riwaka Complex in 1967 led to considerable exploration activity by a number of companies. Various exploration techniques used by these companies are summarised and discussed. Activity of these companies shows that mineralisation is mainly confined to the southern, ultramafic section of the Riwaka Complex where geological mapping recognised sixteen units within, or associated with the Riwaka Complex. Significant pyrrhotite, pentlandite chalcopyrite mineralisation is restricted to biotite feldspar pyroxenites and to clinopyroxenite units. Lesser and more erratically distributed pyrite chalcopyrite pyrrhotite mineralisation occurs in poikilitic pyroxene hornblendites, melanocratic gabbros, and in marginal diorite lenses. It is suggested that a linear belt of layered ultramafic and mafic rocks described in Fiordland by Williams (1974) may be a southern extension of the Riwaka Complex. The Riwaka Complex has been classified as belonging to the Picritic subtype, (Tholeiitic suite), of Naldrett and Cabri, (1976), and as such it is concluded that it exhibits substantial potential for the discovery of economic copper and nickel deposits. It is considered that the complex is a multiphase differentiated intrusion emplaced in a major tensional fracture zone that developed in a relatively stable tectonic environment, namely a succession of middle Paleozoic shallow water shelf sediments. Based on sparse available evidence it is suggested that the Riwaka Complex was intruded in the lower to middle Permian. It is further suggested that the tensional fracturing was initiated by the onset of subduction process which were responsible for the development of the Permian volcanic arcs and ophiolite belt in the north west Nelson area.

Jan 1, 1977

Cyanide-extractable gold is far more meaningful in the definition of ore, and control of extraction, than fire- assayable or aqua regia digestible gold. The use of cyanide- extractable gold addresses the significant problems of over- as well as under-assaying by fire and aqua regia digests. The problems of conventional control or diagnostic cyanidation extractions: lengthy extraction, and masking by pregrobbing in cyanidation extractions for assay purposes; are surmounted with a novel activator - Leach WELL. Full extraction of liberated gold, insignificantly affected by preg-robbers, can now be achieved within 30 minutes. This can assist in reducing common gold losses presently often hidden by inappropriate mine call factors, and/or high grade cut values. This paper includes a discussion of fundamental mechanisms of cyanidation, preg- and assay-robbing, which underlie the phenomena Involved.

Jan 1, 1992

LOCATIONThe property of the Mount Isa Mines Ltd. is situated in Western Queensland, 603 miles by rail west of Townsville, the nearest seaport. All supplies and the bullion are railed between Mt. Isa and Townsville. The climate is semiarid, and operations are conducted throughout the year without difficulty.WATER SUPPLYThe mill make-up water is obtained from the mine, and also from Rifle Creek reservoir, which is situated 20 miles from Mount Isa. The domestic supply of water is obtained from a series of bores on the company's leases.POWER SUPPLYElectric power at 3300 volts, 3-phase, 50 cycles, is supplied from the company's steam power plant, consisting of two units, each unit comprising one Babcock & Wilcox boiler, supplying steam at 300 lb. pressure per sq: in. to one 5000 kW. turbo-alternator. Pulverized coal is used as fuel, and power is being generated at a cost of 0.45d. per kilowatt hour. The coal used is supplied from the State Coal Mine, Bowen, costing 42/- per ton delivered at Mt. Isa.

Jan 1, 1933

By Howell M. W

The purpose of this paper is to outline the main points in the construction of the various types of wire ropes more commonly used for winding in Australia; and the maintenance of the ropes, and cage and skip safety gear as practised at the South mine, Broken Hill.It should be mentioned that both of the shafts at present in use are dry, and both downcast with or without the assistance of the two exhaust fans normally in use: Night shift and week.-end overtime are practicaly non-existent.Thus, during night shift, the cages in No. 7 shaft are landed on the chairs at the surface, providing efficient covers for the· shaft, and allowing the maximum amount of rope to be wound on to the drums. This also applies to the cages of both No. 7 and No. 4 shafts during the week-ends.These factors, combined with electric winding and skip haulage, are calculated to obtain the best use of the ropes when properly attended.WINDING ROPES-TYPE AND CONSTRUCTIONThese ropes may be divided into four main types which will include the more commonly used constructions(a) One-size strand.(b) Warrington strand.(c) Flattened strand.(d) Locked coil.1. One-size strand as the name implies, is a rope the strands of which are constructed 9f wire of the one size.Usually the strands are of 7, 19 or 37 wires.

Jan 1, 1940

By P Bonniwell

As a part of the Newcrest, Telfer Expansion Project, a consortium of Australian, Canadian and South African Mining Contractors in joint venture have been contracted to develop the hoisting shaft. The parties namely; Byrnecut Mining Pty Ltd, Murray and Roberts RUC and Thyssen Mining Construction of Canada Ltd have combined their individual expertise to excavate the shaft. There is a particular emphasis on the use of proven shaft sinking techniques from North America and in particular integrating electric hydraulic drilling equipment and personnel from the Canadian Mining industry. The Telfer hoist shaft when completed will have a finished diameter of 7.1 metres and extend to a depth of 1170 metres below the collar. The shaft will be fully concrete lined and will later be equipped for hoisting ore from the Telfer deeps at a rate of five million tonnes per annum. The shaft when completed will be the largest shaft ever completed in Australia on a volumetric basis. This paper will examine the technical aspects of the shaft sink, as well as exploring the integration of personnel and equipment from the frozen prairies of Saskatchewan, Canada into an operation in the Great Sandy Desert of Western Australia. What are the spin-off benefits for the development of other shafts within Australia?

Jan 1, 2005

By B Mennie, R Poedjono, G Coad

PT Freeport Indonesia operates a large copper and gold mining operation near Tembagapura, Papua (formerly, Irian Jaya), Indonesia. This is a remote location with its own set of unique operational characteristics. The mining and concentrating operations typically produce a concentrate containing 2500 tpd of copper and 6000 oz of gold per day from the combined mining of a 45 000 tpd (ore) block cave operation (DOZ Mine) and a 190 000 tpd (ore) open pit mining operation (Grasberg Open Pit). The Grasberg Open Pit mine will be exhausted in 2015 at which time FreeportÆs operations will entirely underground mining methods. The Common Infrastructure Project (CIP) incorporates the elements required for the shift to underground mining at a production rate approaching 200 000 tpd. The AB Adit portion of the CIP will provide deep level access to the Grasberg Block Cave (below the Open Pit), Kucing Liar, Big Gossan, and the Mill Level Zone orebodies. Commencement of the project was September 2003. The Grasberg Block Cave is planned to start production in 2014. This paper provides details on the project scope, innovative contractual framework, advancement of mining methods throughout the life of the operation, equipment selection, manpower selection, training, geological, and socio-political conditions related to the project.

Jan 1, 2005

The effects of process variables such as solution chemistry, flocculent type and dosage, intensity and duration of mixing, and solids type and concentration, on the performance of flocculation/clarification/thickening processes are described. System response is evaluated in terms of the specific effects on floc settling, supernatant clarity and sediment compressibility. The implications of these results with respect to industrial practice are discussed and general guidelines for direct application to plant design and operation are suggested.

Jan 1, 1993

By Trudinger JP

Mt. Newman Mining Company Pty. Ltd.3 oper ates the Mt. Whaleback iron ore mine in the Ham- ersley Iron Ore Province of Western Australia. The present rate of production of high grade hematite iron ore is 33 million tonnes per year. Mining is by open cut quarrying,with 15m high benches. The present quarry operations will be extended to a large oval pit to win over 1400 million tonnes of iron ore. The pit slopes will extend up to 500m in depth and the perimet- er of the slopes will exceed 15km. Sixty per- cent of the ore is below the water table, which presently lies 45m below the general plain level Dames & Moore, rock mechanics consultants designed the pit slopes during early mine devel- opment to ensure an economic and safe operation.

Jan 1, 1975

A biological column leach testwork program was undertaken on a chalcocite ore. Three tests were conducted in all, using 65 in x 100 mm columns in three sections. The tests were started with varying acid strengths and inoculated with bacterial solutions from previous column testwork. The leaching of Cu was found to occur in three stages. These stages consisted of direct acid leaching, bacterial oxidation and ferric iron leaching. These leaching stages can most easily he described through the examination of not only Cu dissolution but also Fe dissolution and its subsequent oxidation and precipitation. The p11 of the system was found to he critical in establishing and maintaining the bacterial leaching system. The oxidation potential was seen to he influenced by the leaching system as the oxidation states altered. Test variables such as, 02, COz, and temperature were all found to influence the system. Final copper recoveries were in excess of 90 per cent in each column test over a leach time ranging from 211 to 328 days. Given similar leach conditions are applied, the application of this technology to site is expected to give comparable results.

Jan 1, 1994

By Nemcik JA, Gale W. J

The magnitude and orientation of the in situ stressfield has been determined as a key factor in controlling the stability of openings for both coal mine development and extraction. Monitoring of roadway and pillar behaviour in conjunction with numerical analysis has identified specific stress control measures that have been successfully applied to improve productivity in underground coal mining operations. The influence of the major horizontal stressfield on the stability of openings has been identified at a wide range of sites including mines in Australia, Britain, the USA, New Zealand and Japan. Stress mapping, stress measurement and stress monitoring techniques have been applied to define the in situ stress regime and, together with the correlation of measurements of rock deformation and rock reinforcement behaviour, has enabled appropriate stress control measures to be developed. Stress control measures for development headings have required the selection of roadway orientation, roadway sequencing, reinforcement density and pillar size. The monitoring of behaviour at a range of trial sites has confirmed significant improvements in development stability. Stress control measures for longwall extraction have required rational selection of longwall orientation and extraction direction. Where a mine layout design incorporating the optimum longwall layout design has not been possible, the use of sacrificial roadways has been successfully applied to protect key roadways from stress concentration effects. Comprehensive in situ

Jan 1, 1992

By Mutmansky J. M, Organiscak J, Qin J, Bhaskar R

The results of a two-year research study into the relationship between quartz dust levels in host material and in respirable dust in continuous mining sections are presented in this paper. The experimental design and sampling procedures for underground data collection are outlined. The sample analysis procedures for quartz determination, the analysis results and conclusions of the study are discussed.

Jan 1, 1988

Comparatively recent Tasmanian legisla tion established a series of rigid control standards for environmental protection just as ma spectacular expansion of the mining industry was nearing completion. Upgrading existing protection to obtain the necessary licence to operate under these new regulations required further major works and involved a considerable outlay of non- productive capital at a time when escalating costs and falling metal prices were straining economic efficiencies to the limit. Late in 1974 a major environmental protection scheme was commissioned by the Electrolytic Zinc Company of Australasia Limited at Rosebery on the West Coast of Tasmania. This 4 million dollar project was specifically developed by the Company ahead of and to meet the new standards for control of total effluents discharged from its zinc-lead -copper-pyrites mine and concentrator.

Jan 1, 1977

Longwalling has reached a high standard both in Germany and Australia and most improvements should be expected in planning, monitoring and control. Double drum shearer have electric drives to 1000 kW and automatic height control is under development. Conveyor pans to 40mm thickness and chains to 2300 kN breaking load are in use with controls for pretension and load compensation under test.Trends in support are towards two leg shields with loads to 3850 kN per leg and electrohydraulic controls. Expert systems have been devised for planning and diagnosis tasks. With increases in technical standards, staff qualification standards at rising too, drawing attention to training requirements for modem personnel.

Jan 1, 1991

By Aziz N

The objective of the paper is to develop an understanding of the influence of caving on powered support rating by examining the geology and support performance at two sites which represent the current extremes in support rating, ie 6/240 Ton supports operating in the Hirst Seam at Solsgirth Colliery, Scotland, and 4/900 Tonne supports operating in the Bulli Seam, West Cliff Colliery, Australia. A conceptual model is introduced which considers the coal ahead of the face, the powered support, and the caved waste to be three yielding foundations which interact to control the subsidence of the roof strata. Different caving mechanisms are identified for the strata of the Hirst and Bulli Seams, ihese mechanisms being related to rock properties, ie to the palaeogeography and depositional conditions at each site, producing caved wastes with different yield characteristics. The results obtained for convergence and support reaction during production cycles at both sites are analysed to show the manner in which support reaction is developed, indicating the importance of high setting load densities in the Bulli Seam. Evaluation of the work done on the subsiding roof strata during typical production cycles by two of the yielding foundations, ie the powered support and the caved waste immediately behind the powered support, is used to further demonstrate the influence of caving mechanisms on support rating.

Jan 1, 1986