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Mary Kathleen Uranium Ltd. recommenced operations in early 1976 following a twelve year period of care and maintenance. Several sections of the plant were modified or completely changed for the second operation. The most important change was the replacement of ion exchange with solvent extraction as the means of purifying and upgrading uranium rich Isolutions Most of the problems experienced in the solvent extraction system originate from the leach liquor which has a strong tendency to form stable emulsions. This has been countered by some careful control of leaching conditions and by closer observation of operations in the solvent extraction area. Most problems have now been resolved and plant recoveries are quite Satisfactory.

Jan 1, 1978

Classifications of Ni-Cu deposits are based on petrology, geochemistry and the geotectonic setting of host igneous bodies (Naldrett and Cabri, 1976; Besson et al, 1979; Nadrett, 1989). The four major classes in Naldrett's (1989) division rest on the geotectonic setting of the igneous complexes and the classes are further subdivided on the basis of the petrology and geochemistry of the intrusion. A more common subdivision of mafic and ultramafic igneous rocks is based on the environment of rock-forming processes, endogenic or exogenic, intrusive or extrusive, and this subdivision has been applied, in practice, to the classification of sulphide Ni-Cu deposits, too. The extrusive deposits, Class I in Naldrett's (1989) classification, are directly related to volcanic processes whereas all the others refer to the intrusive environment. This paper looks at the differences between the extrusive and intrusive groups of Ni-Cu deposits and presents generic, genetic and structural features of the intrusive group.

Jan 1, 1996

By Gelding P. W, van Herk H

The Cattlegrid copper orebody is a concealed thin, tabular sheet localised near an unconformity between two sub- horizontal Precambrian sandstone units. It extends over an area of 1,000 m by 500 m within a wider area of mineral- isation. The ore consists of complex sulphides and is neither massive nor disseminated. It consists mainly of irregular fillings in pore space developed between clasts in sandstone breccias, in fault zones and joints and along stratification planes. Its habit is unique amongst Australian base metal ore bodies. During the pre-development period ore was outlined by percussion holes but in studies leading to investment decisions ore reserves were manually calculated from intercepts and assay results of cores from diamond drill holes. The methods used for estimating reserves in the pre-production and production periods are described and evaluated by comparing mine production during the first five ore production years with the forecasts made.

Jan 1, 1979

By S Porter, R Woodall, N Weeks

Nelsen, Porter and Wilson (1996) provided some preliminary concepts for the design of the Melbourne City Link tunnels. At that time, the City Link project was in the early design phase whereas now it is nearing completion. This paper provides details of the actual design adopted for the various sections of the tunnels as well as some commentary on the design process. The tunnels form a critical element of the project and the design of both driven and cut and cover tunnel sections is a significant factor contributing to successful project execution. Geology, hydrogeology, site constraints, traffic management and program were important design inputs. Design for the cut and cover sections in particular varied significantly in response to these differing inputs.

Jan 1, 1999

The paper examines the possibility of applying the monolithic packing technique developed in the UK to the division of wide development drivages in Australia, so enabling double entries for longwall retreat panels to be created from shortwall units. The monolithic pack of the UK therefore becomes a monolithic partition in this proposed Australian application. A method developed for the analysis of the load development in packs installed behind longwall advancing faces is adapted and used to predict the support performance of the monolithic partition. Conclusions are made regarding partition construction and possible rates of advance.

Jan 1, 1986

By R W. Wilson, F H. von Glehn

With ever-increasing energy costs and the modern focus on system efficiencies, the practice of æventilation-on-demandÆ is gaining momentum. Several examples, ranging from paper studies to practical examples have been recorded and another recent case study is presented here to encourage the practice. In comparison, æcooling-on-demandÆ has received far less attention. This paper explores the possible merits of this practice by investigating the theoretical response of cool intake airways and the thermal interaction between the air and the rock, in order to gain a better understanding of the system behaviour and to quantify the possible savings. A case study is presented that demonstrates the improvements that can be achieved. Recent developments that allow live interaction between ventilation network models and on-line monitoring systems, have the potential for intelligent active control and alarming of ventilation and cooling networks. This will facilitate and maximise the benefits to be derived from ventilation and cooling-on-demand.

Jan 1, 2005

The crushing and concentration of ores, as Herbert Hoover commented in a footnote in De Re Metallica, stretches back at least 6000 years. During those years there have been continuing changes and improvements in mineral processing technology. It has expanded greatly in its ability to handle different types of minerals, and lower grade and more complex ores. Australia will be dependent on the mineral industry for the fore- seeable future and there will be continuing demands on the mill opera- tors to improve the technology with regard to efficiency, flexibility and costs. These demands will be met successfully in the future as they have been in the past. This Mill Operators' Conference is an important forum for assessing our present position and planning for the future.

Jan 1, 1988

By Craw D

The Southern Alps in the South Island of New Zealand are currently rising rapidly as a consequence of continental collision along the Pacific-Australian plate boundary. Rapid uplift has resulted in a major thermal anomaly in the shallow crust beneath the alps. Alpine topography and associated intense precipitation, coupled with the thermal anomaly are responsible for vigorous combined topographic/convective circulation of water through the shallow crust.

Jan 1, 1995

Maximising margins in highly competitive international markets demands superior productivity. A key to superior productivity is using a process approach to enable rapid, ongoing improvement of production, commercial, administrative, marketing

Jan 1, 1998

By Murray G

This paper outlines the processes involved in acid generation from sulphides and the key factors in identifying and predicting time dependent changes in the nature of acid mine drainage (AMD). The initial characteristics of mine water; whether drainage from exposed mining faces, runoff and seepage from waste dumps or seepage from process tailings; do not necessarily reflect the long term potential for AMD. The ultimate quality of mine drainage is a function of the interaction of many chemical, physical, biological and engineering (operational) factors. Techniques are available that can predict the qualitative nature of acid generation and mine drainage quality but accurate quantitative predictions are essentially impossible at the present time. As more and more mining operations exploit sulphide ore, the AMD and acid waste issue will become a. far greater concern. The significance of time dependent factors in the production of acid mine drainage-.is not just restricted to particuL.ar mine sites but needs to be recognised by the mining industry as a whole.

Jan 1, 1988

By Luck D

Current methods of mucking out small development tunnels are a major limitation to improved efficiency and high rates of advance. This is particularly true in the deep metalliferous mines of South Africa, where the harsh environment, remoteness of operations and the hard abrasive rock conditions mitigate against the use of the tunnel borer type of equipment. The Loader Distributor Train was designed to overcome the special problems of hard rock tunnelling. It combines advanced innovative technology with proven simple methods of operation and maintenance. The system aims at taking advantage of new, efficient and cost effective power sources in South African mines based on replacing compressed air with electro hydraulics and the new concept of hydropower. It also introduces electronics and computer technology, for both automatic control and fault finding, into the production environment. The system is designed to permit sophisticated equipment to be operated and maintained by a semi skilled labour force. Although still undergoing trials it is believed that the Loader Distributor Train will prove highly effective, and that the new concepts offer considerable potential in areas other than flat tunnels, in particular the cleaning of inclined shafts.

Jan 1, 1986

Reconnaissance geochemical exploration in the vicinity of low angle detachment faults which bound the core of the Paparoa metamorphic core complex yielded Au up to 14 ppm, with 35% of greywacke, granitoid and quartz vein samples in the northern range exceeding the 0.01 ppm detection limit. Au is associated with Ag, As, Sb and Cu anomalies consistent with epithermal-type mineralisation. The Ag and Cu anomalies also distinguish this mineralisation from older, mesothermal Au deposits widespread in the Ordovician 'slate belt' greywackes, which comprise much of the upper plate of the core complex. Baryte, molybdenite, fluorite and stratiform U mineralisation in the northern Paparoa Range may also be related to hydrothermal activity along the detachment fault zones.

Jan 1, 1995

Although the flotation cell has been under continuous development over the past 80 years, an understanding of the precise roles of a cell in produc- ing the flotation result had evolved slowly. In fact, detailed studies of cell dynamics began only in the 1940s when flotation practice had almost reached the half-century mark. The earliest generalizations related cell capacity to power intensity (hp/vol- ume) (Rose, 1946), and specific operating features such as aeration and power ' consumption to impeller submergence and operating speed (Read, 1933). In the 1950s hydrodynamic characterization of cells through power coefficients and air flow numbers began (Arbiter and Harris, 1961) and has continued to the present, with increasing industrial use of these concepts (Degner, 1982; Degner and Treweek, 1976). Liquid flow measurements in Wemco cells (Degner, 1982) made liquid flow numbers and turnover frequencies available for more complete under- standing of cell dynamics. The present overview of flotation technology is a critique of cell design. The cell process represents the interactions between cell dynam- ics, cell geometry, and ores, with the latter prepared for that interaction through size reduction and reagent treatment. While previous invest- igations of flotation cells have accepted all cell designs uncrit- ically, the present study considers the physical process components that an effective cell must provide, and then compares a limited number of

Jan 1, 1984

By Hall S. F, Quast K. B Newell R, Ketteridge I. B

For the past six years research funded by the State Energy Research Advisory Commit- tee of South Australia has been conducted at the South Australian Institute of Technology, School of Mining and Metallurgy on South Australian lignites. A major part of this work has been a study of the potential bene- fication of Bowmans lignite using hydrometal- lurgical techniques. The Bowmans lignite de- posit is the largest of its type in South Australia and is a major energy reserve for the state. The utilization potential of this deposit is reduced by its very high insitu NaCl content which presents serious problems for any process. Previous research conducted by Readett and co-workers (1984a & b) has shown that NaCl is amenable to extraction using simple batch water leaching operations. This leaching has been successfully described using a two stage diffusion model derived from first principles based on a simple diaphragm cell.

Jan 1, 1987

Low tonnage quartz vein-hosted stibnite lodes are widely distributed in rocks of the Tasman Fold Belt System in eastern Queensland, with particular concentrations in the Hodgkinson - Broken River Fold Belt and to a lesser extent in the Gympie Province of the New England Fold Belt: Higher grade deposits have been worked intermittently on a small scale since 1873, resulting in the production of about 5500 tonnes of antimony ore/concentrate with an estimated grade of about 55% Sb. Future production of antimony may be as a by-product from deposits, currently being explored/mined for gold in the Hodgkinson/Mitchell River area and the Amanda Bel goldfield. Establishment of an antimony processing plant in Queensland using the Quelar Process would provide a more reliable market for small producers and could stimulate future exploration and production.

Jan 1, 1990

By G Harbort, C Sola

The rapid development of geometallurgy in the mining industry has occurred in relatively recent times. Its importance as an independent discipline in the mineral processing world has been emphasised and recognised. To a large degree, this is the result of a growing understanding of the ore type being processed and their application to provide better metallurgical responses in different mineral processing techniques. The development has matured from early progress through to geological knowledge and into the realm of the metallurgist and mining engineer. Working together, they have developed a powerful framework that will interpret a body of mineralisation into measurable properties.The integration of geometallurgy and operations has become of increasingly important due to improvement in understanding of an orebody as a natural system formed by a number of processes and with a definite fabric of mineralisation within different geological domain. These have to be taken into account when creating techniques that will enable operations to extract the valuable components from a distinct type of ore. Incorporation of such knowledge at an early stage of development, such as the feasibility stage significantly reduces the project risk.This paper is written from the unique perspective of a process engineer embedded within a geological team. It discusses issues such cross discipline communications and misconceptions and details the numerous tricks, traps and treasures of geometallurgy encountered during defining of the Seminco and Taysan resources.CITATION:Sola, C and Harbort, G, 2012. Geometallurgy - Tricks, traps and treasures, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 187-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

The Permo-Triassic Bowen Basin developed during the final stages of the Tasman Orogenic Phase in eastern Australia. The basin has considerable economic value as a source of coal, natural gas and precious metals. The basin, which is of controversial origin, is preserved as a north-south trending, asymmetrical syncline bounded in places by faults. It is here interpreted as a retroarc foreland basin which developed on the landward (west) side of a continental arc associated with continent-ocean plate convergence. Initiation of the basin occurred via back-arc extension in Early Permian times, coincident with a phase of talc-alkaline arc volcanism. Early Permian, mostly marine sedimentation gave away to extensive coastal and alluvial plain depositional systems in Late Permian times, coincident with a resurgence of arc volcanism. Triassic sedimentation was almost entirely alluvial and coeval with westward propagation of thrust sheets from the eastern basin margin. Compressive tectonics climaxed in Middle to Late Triassic times, terminating sediment accumulation and uplifting the entire area.

Jan 1, 1990

By T Ross, S Cameron

The requirement to use explosives in ground temperatures exceeding 50¦C is becoming more common as mines work to maximise the recovery of their resources. Orica Explosives was requested to assist in the development and implementation of æhot blastingÆ safe working procedures at Liddell Coal Open Cut in the Hunter Valley. The mine operator, Hunter Valley Earthmoving (HVE), had to contend not only with elevated temperatures in their overburden resulting from burning coal beneath, but also old underground workings which tended to exacerbate the problem. The paper discusses the following issues:the consultative process that was used to develop the procedures employed to ensure the process could be carried out safely; the technical issues surrounding blasting in hot ground, including temperature monitoring, product selection, application and design to ensure safety and performance were maintained; the need for confidence and trust in the team that was working together in a potentially hazardous environment, the emotive issues that were encountered and how they were addressed; the value of a regular review process combined with open and honest communication to ensure the procedures represented best practice and that all stakeholders understood the process; and the value delivered to Liddell Coal when sterilised areas of coal became accessible with little disruption to the mining process. The paper also discusses the challenges that were encountered in the Reservoir Block where proximity to major power lines and rail infrastructure meant that hot blasting procedures had to also consider vibration limits and the need for Energy Australia to disconnect the power.

Jan 1, 2001

By Swann CA

In order to meet export sales requirements from 1983 onwards, Amcoal developed a new underground mine in the Witbank area of the Transvaal. The mine was required to produce 5 million tons of run of mine coal per annum giving rise to 4 million tons of saleable products. A description of the coal processing plant is given with comments on design philosophy and design parameters. Main features of the coal processing plant are the raw coal handling facilities, centralised control and data capture and the loadout station. The management systems applied during the commissioning period are described. The difficulties experienced and their solutions are discussed. Commissioning was concluded with an independent plant performance test.

Jan 1, 1986

By Jaczkowski B. M, Cox T. J, Domfeh I. A, Stalker I

Mining and treatment of gold ore in the Ashanti region at Obuasi, Ghana has been continuous for more than 100 years. Earlier production from this world class deposit can be traced far into the history of West Africa's gold trade. As part of a general development and expansion program, Ashanti Goldfields Corporation (Ghana) recently undertook a program to heap leach oxidized near surface ore. Kappes, Cassiday & Associates was given a major role in the design, equipment supply, installation and start-up management of the 3000 tonne/day heap leach. Unusual conditions included a high annual rainfall and an ore which could be characterized as a soft, decomposed, water saturated schist. Production began in March 1990. Startup problems and their solutions are discussed.

Jan 1, 1991