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By G M. T, M Zh Bitimbayev, F K. Shadiyev

In the paper a complex problem was formulated for studying and establishing an effective and safe technology of selective underground leaching of useful components from polymetallic ores. Solving this problem will allow increasing technical and economic efficiency, technological and ecological safety of mining of useful minerals of polymetallic deposits.

Jan 1, 2003

The recommendations of a recent American report on "Better contracting for Underground Construction" are considered in relation to Contracting practices on major Australian projects by representatives Of the "classical trilogy" - the Owner, Engineer and Contractor.

Jan 1, 1976

By Rubisov DH

This paper is related to the problems of the mathematical modelling of vibrating screening process and to predicting the screening operation results. The authors propose a model of screening based on the interpretation of granular material segregation on a screen surface as an instantaneous process. Results show an agreement with laboratory and pilot plant tests. Derived formulae can be used for screen sizing and screening result estimating.

Jan 1, 1993

By Conley R, Payne I

The Vickery Coal Mine commenced open cut mining operations in May 1991. All overburden and interburden is drilled and blasted for excavation by dragline or hydraulic excavator. The mode of operation adopted from the feasibility studies requires that throw blasting of the overburden be used to assist dragline productivity.This paper reviews the development of the drilling and blasting practices with particular emphasis on the throw blasting of the overburden and optimisation of costs. This review includes analysis of the pre-production drilling and blasting feasibility studies by comparison with actual results.

Jan 1, 1992

By Lewis RW, Wilson GI

An ore reserve estimation is only as meaningful as the quality of the data used. All required information needs to be collected in a careful and systematic manner, and be rigorously checked and verified before estimation commences. In addition to geological, assay and location data, a large variety of other information is required for the estimation process. This includes mining, metallurgical and environmental parameters. Though outside their usual area of responsibility, geologists should be involved in the selection and collection of this additional Information.

Jan 1, 1987

By D C. Laurence, J Holden

Seafloor massive sulfide deposits contain bonanza grades of gold, silver, copper and zinc metals. The deposits are often found at depths of one kilometre or more. They are characterised by active chimneys or smokers venting fluids at over 300¦C, with extremely low pH values. Mining of these deposits presents risks for both industry and governments at orders of magnitude higher than terrestrial mining This paper briefly discusses some of the core risks concerning the development of SMS mining including: technical, economic, environmental, legal, social, and research and development. Until and unless these risks are eliminated or minimised, the embryonic deep sea mining industry will remain just that, and these deposits will remain a fascinating, unexploited geological curiosity.

Jan 1, 2003

By Hosking JW, Muir DM, Ruane M, Smith I. Hinchliffe WD

Maintaining carbon activity is critical to the satisfactory recovery of gold in the Carbon-in-Pulp (C.I.P.) process. Reduced activity can lead to gold losses in tails and lower tonnage throughput.Carbons from a number of W.A. C.I.P. circuits have been examined for the extent of fouling by inorganics such as calcium, magnesium, copper, nickel and silicon. Many of these carbons have exceedingly low activity leadingto low gold loading and excessive contact times. The relative importance of these fouling agents and cyanide levels on carbon activity is discussed. Mathematical modelling shows that relatively small improvements in kineticactivity lead to much lower tank volume require-ments and carbon residence times.

Jan 1, 1984

By W F. Bawden, J T. Paynter

This investigation involves laboratory testing and stability analysis of paste fill at the Golden Giant Mine. Site-cast samples are tested in unconfined, confined, and consolidated-undrained triaxial compression. Pore pressures during shear and consolidation characteristics are measured to determine both drained and undrained shear strength parameters and assess the potential for undrained loading. Liquefaction potential is also considered. A limit equilibrium solution is used to obtain factors of safety against failure of the fill during mining of adjacent stopes.

Jan 1, 1998

By Carlie JC

Many low sulphidation epizonal gold and zinc-lead vein deposits within magmatic arcs are situated on basement highs, and post-date both the main volcanic episode and porphyry copper (gold) mineralization. These features are best explained by emplacement of a flat batholith a few kilometres beneath each mineral district, as recently demonstrated by geophysical data in the Baia Mare district of Romania. The batholith provides heat for the hydrothermal system, and results in extensional faulting both through up-doming of the overlying rocks, and in some arcs through incipient collapse of the thermally weakened crust under regional extensional stress. More water-rich magmas emplaced at greater depths could explain some deep epizonal and mesothermal gold deposits situated outside magmatic arcs.

Jan 1, 1995

By K Steamy, D Lesmana, K Yulia

Effective selective mining relies heavily on high quality geological data and assay data. Such assay data is dependent on effective sampling protocols, sample preparation techniques, assaying practices and well founded quality assurance/quality control (QA/QC) procedures. This paper describes recent developments in grade control sampling at PT Nusa Halmahera Minerals high-grade Kencana gold mine at Gosowong Indonesia and presents a case study in identifying, minimising and monitoring random and systematic sampling error including the use of duplicate sampling and the Thompson Howarth technique for quantifying random sampling error.

Jan 1, 2009

By Thompson IR

This paper describes a Client Consultant Relationship and shows how an engineering team created an environ- ment which fosters the development of good, economical and sometimes unique solutions. A major factor in establish- ing this environment was the Client's instruction to the Consultant to "propose solutions which, in the Consultant's considered opinion, best satisfy the needs of the project - not necessarily solutions which reproduce methods adopted elsewhere in the past." The Consultant's experience in other projects and disciplines outside mining has contributed by providing a cross- fertilisation of ideas. The team approach also allows the Client's expertise to be applied positively throughout the design process. These factors and the Client's foresight in providing adequate time for planning, allow the Client-Consultant Team to apply sound fundamental engineering in developing effective solutions.

Jan 1, 1975

By Kepplinger W

The COREX process is a technology for production of liquid hot metal on the basis of coal (without the use of a coking plant) developing by VOEST- ALPINE AG, Austria and its subsidiary company Korf Engineering GmbH, Federal Republic of Germany. CORED is a registered trademark of VOEST-ALPINE AG and Korf Engineering GmbH. The COREXW process is based on the idea of separating the process steps realized in the blast furnace (gene- ration of reduction gas, reduction of iron oxide and melting of the reduced iron) and including partial coking of the coal.

Jan 1, 1987

A methodology is described to integrate heap leaching into a CIP operation. The paper firstly describes what is meant by a 'systems approach'. A broad view of the objectives of integration of heap leaching into CIP is given, followed by the components of the system, and then a description of the methodology for integration. The seven stages of integration are given as determination of distribution of gold, sampling, metallurgical testwork, conceptual study, pilot heap operation, pit modelling and pit optimisation. The final result is a series of optimised curves which determine the maximum value of the orebody, and the optimum cut-over grade from CIP to heap leaching.

Jan 1, 1992

By P Heppner, J Schell, R Newell

The effect of various methods of conditioning on subsequent flotation performance was reviewed, where complex interactions involving attrition, aggregation, dispersion and surface cleaning were discussed. The present study focussed on the influences of standard laboratory cell conditioning, ultrasonic dispersion and high intensity conditioning on copper mineral flotation characteristics. The effect of substituting demineralised water for the WMC plant water was also examined. It was found that higher copper concentrate grades were often obtained using demineralised water, however the use of high intensity conditioning in mill water gave the highest copper recovery and highest flotation rate constant. This process should be considered if copper grade and recovery in this section of the plant drops, especially if the drop is due to surface oxidation of the copper minerals. Other methods of conditioning (cell and ultrasonic techniques) improved the rate of copper flotation above that obtained in the virtual absence of conditioning, showing the importance of conditioning on subsequent flotation operations.

Jan 1, 2000

An international raw material partnership, a $164 million 900,000 long ton per year aluxAna plant; an ideal location at Gladstone, Queensland, Australia - this is Queensland Alumina Limited, on stream in 1967 expanded 50 per cent by the end of 1968. Queensland Alumina Limited is the world¦s most modern alumina refining operation which is owned by an international consortium of four companies; Kaiser Aluminum & Chemical Corporation of the United States with 52 per cent; Alcan Aluminium of Canada with 20 per cent; Pechiney of France with 20 per cent; Conzinc Rio Tinto of Australia, 8 per cent. Q.A.L. operates as a co-operative -- the partners do not draw profits from the venture. Instead, each member of the consortium draws alumina in proportion to his share of the ownership. The method of disposal of this alumina is for the partner to decide.

Jan 1, 1969

The implementation of the Mining Further Amendment) Act, 1970, and later the Coal Mining Act, 1973, placed a requirement on the Department of Mines to accept an initiative in relation to coal exploration and coal mine development which does not apply in the case of other minerals. It is necessary to consider the exploration of the total coal resources of the State when considering exploration rather than one individual basin or deposit. If the level of knowledge of the coal resources in these basins is considered in relation to their potential for development it is possible to allocate broad scale priorities to their assessment. Due to the enormity of the task which involves a conservative estimate of in excess of 400 000 m of drilling to reach a broad reconnaissance level of understanding the involvement of industry with the Department in the exploration programme is necessary. The development of the coal deposits by mining operations must give consideration to a number of constraints apart from the simple availability of the resources. Principal among these are aspects

Jan 1, 1976

The resource sector is conservative industry and people are resistant to change. The methods and procedures used to implement changes in process plants ultimately determine the success of such changes. The financial managers have a large say in where money is spent and the technical personnel must justify the cost and benefits for any expenditure. There are also others who believe it canÆt be done û æwe tried thatÆ. Implementing change needs a æChampionÆ who can assess the risks, plan, define the objectives and scope, set the goals, determine the key performance indicators (KPIs) and stay focused. This also requires preparing a budget and schedule and measuring against this. Contract management, reports and reviews are part of the implementation. Several case studies are given as examples of the implementation of process design changes to highlight the critical aspects involved.

Jan 1, 2009

The Burra Burra Aline is in complexly folded Torrensian dolomites and limestones forming the faulted axial region of a major anti cling. The orebody mined was largely of secondary origin and confined between two faults, Kingston's on the west and Tinline's on the east. The orebody occurred at the junction between cherty dolomites and a clastic limestone with a large mass of marble breccia along its western margin. Secondary ore consisted of carbonates and oxides in the breccia and the ore bed and detrital copper minerals deposited. As part of a clastic breccia in sink holes and solution cavities in the dolpthites and ore beds.Primary sulphides occur disseminated in the marble breccia and in stratiform habit in the ore bed. Kingston's so-called 'Lode' may be mineralised marble breccia.The marble breccia appears to be of diapric or sedimentary origin and there is evidence to support a sedimentary origin for some 'of the copper sulphides. No igneous rocks have been discovered within 20 miles of the mine and any hydrothermal activities were probably at comparatively low temperature. The possibility of extensive stratiform and disseminated copper sulphide mineralisation in the marble breccia and ore bed requires testing by further drilling and geophysicalsurveys.

Jan 1, 1963

The efficient development and exploitation of an orebody relies on an understanding of the mineral characteristics of the deposit. This information is valuable throughout the mining cycle - during exploration, assessment, testing, design, operation and rehabilitation. Problems can arise at each stage if there is an inadequate appreciation of the mineralogy involved and its effects on the treatment process. Modern image analysis systems now permit a more quantitative understanding of the mineralogy of an ore to be gathered. Where previously the metallurgist had to rely on qualitative information to guide technical decisions, it is now possible to give numerical estimates to the compositional and textural properties which govern the mineral concentration processes. Ore samples can be characterised according to modal abundances, mineral grain size parameters and mineral associations, all of which affect the liberation and concentration of the values. The paper will discuss the application of quantitative process mineralogy by considering a number of case studies. These include: ore characterisation to assist in exploration, assessment and mine planning; modal analysis of complex mineral suites to assist in the evaluation of ores, the deportment of values between products and the recovery or loss of these values; liberation analysis for ore testing, plant optimisation and performance monitoring; and characterisation of tailing to guide estimates of leachability, stability and rehabilitation options.

Jan 1, 1998

By A D. Bugarski, B R. Conard, G H. Sc

The objective, of the Diesel Emissions Evaluation Program (DEEP)-sponsored project at IncoÆs Stobie mine, was to conduct a long-term field evaluation of selected diesel particulate filter (DPF) systems, available to the underground mining industry. Nine state-of-the-art DPF systems were retrofitted to heavy-duty and light-duty vehicles and were subjected to extensive long-term in-mine evaluation. Periodic efficiency tests were conducted at various stages of the study (in 2001, 2002 and 2004) to establish in-use efficiencies and durabilities of the tested DPF systems. During efficiency tests, the vehicles/engines were operated over several steady-state operating conditions. Various instruments were used to measure particulate and gaseous emissions upstream and downstream of the filter systems. The results were used to assess the effects of the filter systems on the concentrations of diesel particulate matter (DPM), nitric oxide, nitrogen dioxide and carbon monoxide in the vehicle exhaust. Experience with the operational issues related to deployment of the filter systems on underground mining vehicles, coupled with the assessment of the filtration efficiencies, were the primary objectives of the study. The variety of filtration systems and regeneration concepts used in this study offered the opportunity to investigate the advantages and disadvantages of the various types. Some of the major issues studied were criteria for selecting the filter media, means of regeneration, the long-term operational reliability, and the occurrence of unwanted secondary emissions.

Jan 1, 2005