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By Delahey G, Dunne R

At New Celebration Gold Mine the advent of treating primary sulphide ores resulted in decreased gold recoveries of four to ten per cent. The grind coarsened due to an increase in ore hardness and gold in the residue was found to be associated with pyrite. Finer grinding improved recoveries but was impractical as production rates would have decreased to unacceptable levels. An alternative approach that has proved to be viable combines both gravity separation, to recover the coarse gold bearing sulphides, and then regrinding the concentrate in a tower mill prior to releaching in the cyanide leach circuit. The tailings treatment plant was commissioned in December 1990 and details of the first 18 months' operations are Provided.

Jan 1, 1993

By Baczynski NR, Fagan MJ

A 3050m long section of a 1.65m internal diameter tunnel is presently under construction in the Brisbane area by means of the pipe-jacking method. The soils along the alignment had been deposited in a deltaic/estaurine environment and rapid changes in soil type occur. The tunnel passes beneath several extensive bodies of surface water. Groundwater problems have been experienced with tunnelling through alluvial sands and gravels. Details of the ground conditions, the pipe-jacking method used and tunnelling experience are discussed in this Paper.

Jan 1, 1987

By Nairin J. D, Hayes P. C

Detailed studies of the microstructures and compositions of zinc and lead blast furnace sinters have been undertaken. An analysis of the results obtained has indicated that in many cases the microstructures of these complex materials can be explained by the solidification of melts from pseudo-ternary phase systems. Further laboratory studies have been carried out to more accurately determine the extent of primary phase fields and the liquidus temperatures in the appropriate binary and ternary systems. This approach shows considerable promise in simplifying the descriptions of slag systems used in oxidising and reduction smelting processes for lead and zinc recovery.

Jan 1, 1992

By A Black, J H. Youngson

At least 85 000 tonnes of mine tailings were discharged into Deepdell Creek, east Otago between 1890s and 1940s. The tailings contained about 1 wt % arsenic, so about 850 tonnes of arsenic in the form of arsenopyrite was discharged. Annual floods have removed nearly all tailings within c. 60 years. Small amounts of arsenic-bearing sediments (<250 ppm) remain in Deepdell Creek. About 7 kg/year dissolved arsenic was discharged in groundwater from mineralised Hyde-Macraes Shear Zone rocks in the vicinity of the historic mine sites. Adsorption of this arsenic on to iron oxyhydroxides in the stream sediments may have contributed to the elevated As content of those sediments. Even less arsenic remains in the main Shag valley below the Deepdell Creek confluence (15 - 25 ppm As). Rare relict arsenopyrite grains are trapped in bedrock crevices 25 km from source. No tailings deposition is detectable in theShag River estuary, and the tailings have presumably been discharged into the sea. Natural rehabilitation of the Shag catchment has been rapid and effective.

Jan 1, 2004

By Hinrichsen H. D, Rathburn D. R, Stieger W

The present situation in the field of iron ore pelletizing is briefly described with particular view of the Lurgi/Dravo travelling grate process. To meet todays pellet quality requirements with regard to physical and metal- lurgical properties it is often necessary to add basic fluxing materials. It has been de- monstrated that for certain ores, basic addi- tives provide a considerable improvement in fired pellet quality. The production of self- fluxing pellets is becoming increasingly attractive. One Lurgi/Dravo plant is now in operation and another is under construction which were designed for the production of self- fluxing pellets. Self-fluxing pellets may be considered as the primary or exclusive blast furnace burden and the installation of a sinter plant is not necessary if the pellet plant-can handle all in-plant fines. Reference is made to the first pellet plant utilizing iron ore concentrate, in-plant fines and basic flux. The use of solid fuel for pellet indura- tion is discussed because of the increasing prices and possible shortages of heavy oil and natural gas. Since there is a strong tendency to increasing plant capacities, the design fea- tures of travelling grate pelletizing plants for productions up to 6 million tonnes are Discussed.

Jan 1, 1974

The elements of consistent structural de sign models for underground structures are explained. Such models should comprise at least ground properties, excavation and support methods, computational models for analysis, failure hypotheses, and in-situ monitoring. The fundamental characteristics of the interaction between ground and support are investigated. Then, plane strain models for soft ground tun- nelling and design models for rock tunnelling employing stress release at the tunnel face are elaborated. Some numerical evaluations are gi- ven in diagrams, comparing approaches of dif- ferent authors. Comments are presented on nume- rical three-dimensional models (visualized by structural models for mining in rock salt), on the interaction of in-situ monitoring and design, on structural safety for underground structures, and finally on the general develop- ment of structural design models in geo- Techniques.

Jan 1, 1987

Both as an energy source and as a raw material, natural gas is playing an increasingly important role as a catalyst for the development, continuation and rebirth of mining projects in Australia. Pipelines are the vital link in making natural gas available to a region and to individual mines. This paper will cover the role of pipelines in supplying mining projects in Australia, the development and status of the Ballera to Mount Isa gas pipeline and the future prospects for gas pipelines in the Carpentaria Mineral Province.

Jan 1, 1998

By J J. Campbell, G J. Wilkie

The ores of the Golden Mile exhibit considerable complexity. As a consequence, the operating company, Kalgoorlie Consolidated Gold Mines (KCGM), considered it important to develop a coherent database of information describing the nature of the many ore lodes in terms of (1) rock properties and mineralogical content, including relative proportions, grain size, associations and deportment of key elements between minerals, (2) the relative behaviour of consituent minerals in various stages of processing and (3) the nature of the final products and key intermediate streams. The paper describes a sequence of metallurgical tests covering comminution, flotation, gravity concentration, leaching and calcining, carried out on three lodes of the Golden Mile. Key samples generated by the testing were subjected to comprehensive size-by-elemental assaying and QEM*SEM mineralogical determinations of sulphide and precious metal associations. Significant differences between lodes were identified, and the impact of these differences on processing is discussed.

Jan 1, 1998

Alluvial gold exploration is aimed at recognizing areas of anomalous gold content as evidenced by the nature of the drainage system, its age, geomorphic history and other features of the geological environment including the provenances. Subsequent studies to quantify the findings are governed by the need for accurate data based upon precise measurements. Computerization allows the use of more complicated mathematical procedures than are feasible manually, thus promoting the development of more advanced technological aids. Data banks provide the means of storing vast quantities of information for instant recall.Sample representivity is a major problem and a clear understanding of both sampling and analytical requirements is essential for dealing with problems arising from variations in sample size and particle size distribution. Field samples must always be large enough to ensure adequate representivity or the sampling has failed in its purpose.

Jan 1, 1984

THE filter-press, which has done so much for the successful-treatment of the sulpho-telluride ores of Kalgoorlie, has a serious rival in the vacuum process, and this paper is written with a view to arousing more interest in the cheaper working of the press, it being doubtful whether its efficiency in extraction can be improved upon. Before proceeding with the actual working of the press, it may be as well to make brief mention of the character of the ore treated at the Associated Northern Blocks, where these notes were compiled. A sample from several weeks' run was taken of the raw ore, with the following analysis...

Jan 1, 1911

By M McCarthy

Over the last six years Mandalay Resources has increased production rates and improved safety outcomes at its Costerfield mine in Victoria, Australia. This mine is an underground operation utilising narrow mining techniques to extract vertical veins, and produces up to 80 000 equivalent ounces of gold per annum, in both gold and antimony value.The operational challenges of narrow vein mining include controlling overbreak when veins being mined are only 300 mm wide. The mine has developed methods and modified equipment to suit extraction of these veins. Productivity improvements over the period have involved development of a stoping method and equipment to suit 1.8 m wide development drives. Over the last five years and during a skills shortage, recruitment, training and retention of personnel has been key to keeping corporate knowledge and skills to execute a careful efficient mining technique to minimise overbreak.Managing an underground operation close to nearby residents has unique challenges. Historically Victorian residents had family members work as underground miners; however, in the current day with few underground operations in this jurisdiction, community knowledge of mining has decreased. The Costerfield Operations are only 100 m from the nearest residence and the company values community engagement, partnership and investment with local Heathcote organisations.The mine has invested substantially in executive coaching of its leadership team early, which has paid dividends in problem solving potential of that team and ensuring the operation delivers on its promises to all stakeholders. The operation has become safer and employees are now more aware of their individual contribution in producing safe, efficient gold and antimony that benefit the whole operation, community and the region.CITATION:McCarthy, M, 2016. Costerfield – a narrow vein case study, in Proceedings International Mine Management Conference, pp 331-338 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

By Rigby D, Gould K. W, Hart G. H

The variation in chemical and isotopic composition of hydrocarbon gases generated from humic source rocks in the Cooper Basin, the orth West Shelf, the agoorin oil shale deposit. ollinsville and the southern Sydney Basin is reviewed, discussed and interpreted.The primary composition of gases generated in and released from such source rocks appears to be very largely controlled by the degree of dispersion of the organic material. For example in eoaly shales, where the degree of dispersion may be high, products as generated may escape into surrounding inorganic structures where further maturational reactions may proceed. On the other hand, when the organic materials occur in massive form, as in coal seams, the hydrocarbons generated tend to be retained within the coal. Further cracking to the stage of methane generation is usually required before release of hydrocarbon products is significant.Secondary factors of importance in determining seam gas composition in the Bowen (Collinsville) and southern Sydney Basins are the invasion of coal measures by carbon dioxide from external magmatic sources and/or the vertical diffusion and loss from the surface ofgases generated at depth.Isotopic measurements of gas composition have been particularly valuable in determining the origins and histories of the gases examined, in demonstrating when gases are of mixed origins and in the prediction of gas quality in exploration.

Jan 1, 1985

Our ultimate resources come from the Sun and the Earth System. At this time we face a world crisis in energy, water and soil resources. Global pollution problems are increasing in almost all nations. There is an urgent need to use our vast knowledge with a new wisdom and this requires new integrated teams of experts to provide the best alternatives for the needed new development problems. These teams must include economists, engineers and a broad spectrum of scientists. Today it is possible to produce clean energy, stop soil erosion, clean water and reduce and use wastes of many types.

Jan 1, 1995

Having provided basic data in the main paper I would now like to move on to discuss these areas in broader terms and to examine the various coalfields in terms of their tectonic setting and depositional environment and ultimately to make some brief comments on the factors which may have controlled deposition.

Jan 1, 1975

In the first half of 1987 two four metre diameter raise bore holes were drilled at the Olympic Dam Project for ventilation purposes. The first hole, 476 m x 4.0 m diameter was completed in 96 days, 35 days longer than scheduled. The second hole, 407 m x 4.0 m diameter was completed in 39 days, 2 days ahead of schedule. Both holes were drilled with a Robbins 121R rig using a Wirth head that consisted of 23 face cutters and 5 side cutters, supplied by a contractor. After the sites were located a grouting program was carried out to help seal off an aquifer between 160 and 180 m below the surface. Cavities discovered in the Andamooka Limestone were filled with concrete. Because of the overlying dune sands and clay both sites were pre-sunk to the competent Andamooka Limestone.

Jan 1, 1988

When lying over 200-250m depth, many seams and surrounding strata are gassy enough to create mining difficulties , particularly in highly productive longwalls as well as in their development headings. In addition to the gassiness of seams or stra- ta in the outgassing volume around working, the shape expansion and limits of this one influences much the intensity of gas emission. These charac- teristics of outgassing volume differ very much ac- cording to the permeabilities of the seams and strata encountered by their fracturation due to mi- ning. Moreover, the shape of the outgassing volume is very much modified by the rate of advance of the face. In nearly impermeable deposits, gas flows from a limited outgassing volume. When the rates of advance of a face are medium or low, the shape and dimensions of this volume do not change very much and outgassing volume is translated progressi- vely with the face advance. This explains why, in the past, it was observed that there was for each seam an average steady specific emission of gas, round which the volume of gas evolved per mined ton or per mined unit area, calculated over a cer- tain time, was oscillating. Combined with a statisti- cal irregularity coefficient, this allowed prediction gas of emission and thus to take decisions for air ventilation, drainage, and eventually production.

Jan 1, 1988

Various software packages are discussed. These are components of an Integrated Planning and Scheduling System developed by MVM with the aim of providing up-to-date information for the Whaleback operation on: 1. Mine Topography. 2. Status of equipment in the mine. 3. Material moved from and within the mine. 4. Volume and density of same. 5. Quality of same.

Jan 1, 1986

Blasting is a common practice in mining whereby solid rock is fractured, using explosives, to a more manageable size. The effectiveness of blasting influences a number of downstream activities such as shovel digability, crusher throughput and mill throughput. As the cost of explosives is relatively low compared to milling costs (mainly due to power consumption), blasting practices can be optimised so that the downstream processes are made more efficient, and an overall cost saving made. This is the basis of the Mine to Mill approach. The effectiveness of the blasting is influenced by two main factors, the blasting practices used (eg explosive amount and type) and the geology of the area. As the geology cannot be altered, the blasting practices must be refined to create optimum blasting. Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston operation, located in the heart of the Kalgoorlie Goldfields is the largest gold mine in Australia. Mine to Mill at KCGM has had varied success, with initial positive indications being lessened by a number of factors, including the increase in the amount of voids.

Jan 1, 2003

Gunpowder Copper Limited processes 1,000 tonne/day of Mammoth ore in a conventional flot- ation concentrator. Run of mine ore is prepared for flotation by three stages of crushing and two stages of ball milling. The concentrate, in which the primary copper mineral is chalcocite, is solar dried and exported to Japan. The history of operation is summarised, and plant practice and metallurgical problems are discussed.

Jan 1, 1974

Introduction.History of Stope Filling at Mount Isa.The Need for a Systematic Fill Programme.Reasons for Filling.Fill Materials and Tonnages.Rough Mullock Fill.Quantities Readily Available.Fill Pass Development.Stope Preparation.Drainage.Hydraulic Sand Fill.Initial Experiments with Mill Tailings.Surface Layout.Operation Procedure.Underground Pipe Lines.Life of Sand Pipes and Cones.Drainage.Old Tailings Dam Sands.Quantity of Fill Placed.Pillar Tonnages.Conclusion and Acknowledgment.INTRODUCTIONFilling practice outlined in this paper refers exclusively to the Black Star section of the mine. The stope filling necessary early in the life of the Black Rock and portions of the Rio Grande sections is not to be confused with the current filling programme.

Jan 1, 1953