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A computer programming language known as GPSS is described and possible applications for the mining engineer are presented. The language is continually being upgraded with improved versions appearing about every three years. The tremendous power of the language is considered by comparing it with standard engineering programming languages, such as Fortran or Basic. Sample problems that can be solved using the language are indicated. The advantages and disadvantages of the languages are also discussed.

Jan 1, 1987

A short study showing how first dry fill and later hydraulic sand fill has allowed mining to continue immediately adjacent to worked out areas in a mine 75 years old. This paper is a case study of filling in an old mine where for 30 years filling was not important until ground troubles were experienced after a series of parallel shrink stopes were pulled empty., Dry fill was distributed from the surface via a system of passes and conveyor belts. With the stabilization of the ground it then became possible to continue mining beside and above the old stopes using totally sealed and decanted hydraulic sand fill. A brief description of the dry fill is given and then more technical details of the hydraulic fill. The necessity for a well trained and experienced hydraulic fill crew is discussed along with the problems of filling small stopes in broken ground.

Jan 1, 1973

Incremental sampling is defined as a solution to fight segregation, the theory is demonstrated and theoretical and practical aspects are discussed. The number of increments necessary for successful sampling is discussed. As an application, riffle splitter division is reviewed.

Mar 1, 2010

By P Mavros, K A. Matis, N K. Lazaridis

A large number of techniques are in use today to limit membrane fouling, among them certainly is air bubbling (which constitutes the transport medium in flotation) as applied in wastewater treatment; meanwhile, dispersed-air flotation is suitable as a pretreatment stage for microfiltration. The invented and investigated hybrid cell combines the advantages of both flotation and membrane separation, while overcoming their limitations, producing clean water from industrial wastewater. Metals recovery from dilute aqueous solutions is a promising application of this innovative hybrid process of flotation and microfiltration, further to solid/liquid separation. In this study, ceramic flat-sheet membrane modules were inserted inside a typical flotation cell in the laboratory tests, using multichannel geometry, combining flotation with microfiltration by submerged membranes; the latter requiring periodic backflushing. The specific objective was to apply this process for the efficient separation of effluents containing metal cations (here, zinc). The main examined parameters were: the initial metal concentration, flotation surfactant applied and air flowrate. The successful contribution of precipitate flotation was highlighted, while the observed metal removals were of the order of ~100 per cent.

Jan 1, 2005

The integration of economic, cultural, social and environmental decision-making has increasingly become globally recognised as the only acceptable way of doing business consistent with sustainable development. This concept requires a move to a new economy, where environmental, cultural and social issues are accounted for and integrated in business decisions and practice. There has been much discussion on sustainability and sustainable development, but organisations are still grappling with what this means in reality for their business and how they should respond. The challenge is to take the way we do business to a new paradigm and make solutions relevant to business. This paper will look at some of the strategies and programs being adopted or considered by resource companies as they move towards a more sustainable future. These include defining a sustainability framework for their organisation, developing the business case and planning approach. Also included is a brief overview of some of the new approaches to environmental management, such as reducing materials and energy intensity, minimising or eliminating impacts through better waste and emissions management and process control, taking a whole of life approach to products and conserving resources. The concepts of Product Stewardship, Eco-efficiency and Cleaner Production will all be discussed.

Jan 1, 2002

By H Aral, L Malishev

The carbothermic chlorination of titaniferous materials such as rutile, synthetic rutile (SR), upgraded slag and ilmenite in a fluidised bed is an established commercial process. In this work, ilmenite sourced from the Murray Basin area of South Eastern Australia was chlorinated and an assessment of the chlorination characteristics of the ilmenite, in terms of pre-treatment, type of reductant and reaction time was made. Selective chlorination of Murray Basin ilmenite to remove Fe and Mn was achieved in this work. A synthetic rutile sample containing around 93 per cent TiO2, one per cent Fe2O3 and 0.5 per cent MgO was produced at a chlorination temperature of 1000¦C with around 25 per cent loss of Ti as TiCl4. Raising the reductant to ilmenite ratio in the chlorination reactions increased the amount of Ti chlorinated. However, complete chlorination of Murray Basin ilmenite to produce FeCl3 and TiCl4, was not achieved under the conditions used in this work. Pre-oxidation of Murray Basin ilmenite before chlorination had little affect on its reactivity, compared with æas receivedÆ ilmenite. In contrast weathered West Coast ilmenite chlorinated appreciably better than West Coast primary ilmenite, in terms of bed residues remaining and amounts of elements removed. The presence of large amounts of Mg and chrome spinel grains in the Murray Basin ilmenite used in this study are likely to make it difficult to chlorinate directly in a commercial chlorinator. However, this is not to say these ilmenites will be unsuitable for chlorination applications. Further work is needed in the separation of Mg and chrome spinel grains from Murray Basin ilmenites and the products resulting from these tests could then be assessed in terms of chlorination performance, so that further processing options can be explored.

Jan 1, 2000

A major problem with many items of underground equipment is that they have either been converted or adapted from surface equipment, or that they have been designed and assembled in comfortable offices and factories with adequate lighting, specialised tools, and ample space. As soon as they are in use underground in cramped spaces maintenance frequently becomes difficult, parts are awkward to change, and a whole range of accidents can happen.Similarly, ingenious operators discover a whole range of uses for which the equipment was not designed, such as using a loader bucket for a work platform, or scaling backs with it.Design modifications of equipment and removal of hazardous components that can trap limbs is expensive when the dangers are discovered in operation, sometimes posthumously, and it is not surprising that workers compensation insurance premiums are high. The cheapest place to ensure that equipment is safe is in the design office, where the operator should be considered first, rather than being added to a purpose built machine as an afterthought.

Jan 1, 1992

This short paper outlines the authorÆs views regarding the progress we have made as an industry in managing mining assets over the past 500 years. It represents a personal view û but one founded in fact-based observations of mining companies and of the mining industry in general. There is no doubt that AgricolaÆs views as expressed in De Re Metallica (1556) were visionary. There is also little doubt regarding another issue û that whilst a great deal has been learnt about the management of mines since AgricolaÆs time, observations suggest that best practice management is the exception rather than the rule across our industry. Although insights regarding the successful management of mines have become apparent, we still witness unnecessary errors in our industry that lead to the loss of shareholdersÆ funds. By highlighting some aspects of current best practice, particularly in the arena of operations management, it is hoped that this short paper contributes a small step along the next 500-year-long learning curve. The paper concludes with a brief description of the progress and impact of continuous improvement initiatives at Kalgoorlie Consolidated Gold Mines (KCGM). Located in the Kalgoorlie Goldfields, KCGM is currently AustraliaÆs largest gold mine producing over 800 000 ounces of gold per annum. Improvement initiatives at KCGM look set to deliver some $100 million in value over life-of-mine.

Jan 1, 2004

Zinc produced by pyrometallurgical processing techniques suffers the disadvantage of restricted market potential because of its impurity contents, typically lead and cadmium. Market zinc to the Special High Grade (SHG) standard can only be produced by reflux distillation refining, which is costly in terms of energy and equipment, and potentially capacity limiting. Recent published laboratory work suggested that molten salt electrorefining of zinc metal is a potentially much cheaper alternative to the reflux distillation refining. The extrapolation of the laboratory results to an industrial configuration, however, resulted in an estimated power consumption for electrorefining and associated costs offering no advantage over current reflux distillation practice. A review of this estimate now shows that a serious error in calculation was made, and that the energy consumption for the electrorefining of molten zinc would be an order of magnitude lower than that for reflux distillation refining. While this is a promising indication, further research is required before development towards an industrial scale operation is warranted. This would particularly relate to the extent to which adverse electrolyte deterioration may take place and its potential effect on the anode and cathode efficiencies of the process. This paper considers the laboratory investigations required to explore the industrial potential of the molten salt electrorefining of zinc and foreshadows some of the practical problems to be solved in further development.

Jan 1, 2000

While there is reasonable agreement on the basic chemistry of the slag fuming process, there has been an on-going debate for nearly 50 years as to the nature of the rate controlling factors in its industrial application. There have been advocates in the technical literature for thermodynamic limitations on the one hand or kinetic limitations on the other. The different viewpoints result in very different predictions as to the technical and commercial potential of the process. A resolution of the debate becomes of importance as pyrometallurgical processes are advocated as a means of extracting environmentally deleterious elements from metallurgical wastes. The present paper reviews the arguments in favour of both equilibrium and kinetic control and puts forward the view that much of the evidence for limitation of the process by kinetic factors under all conditions is unconvincing. It is maintained that the process can approach thermodynamic equilibrium under industrial conditions and that this determines the ultimate limitation on its technical performance. It is acknowledged, however, that kinetic considerations may cause the batch process to fall well short of performance predicted on thermodynamic grounds. The strong process limitation arising from the influence of chemical thermodynamics on the likely outcome of a hypothetical continuous fuming process is contrasted with optimistic forecasts resulting from the extrapolation of process models based only on kinetic considerations.

Jan 1, 2000

By M P. Schwarz

A major issue presently faced by companies producing and processing iron ore is the need to maximise throughput while minimising capital expenditure. While present high demand means this is of prime importance, the perennial issues of maintenance, operating costs, reliability, quality and environmental sustainability are also critical to profi tability. Attempts to address these issues generally require modifi cations to existing equipment, or trials of new equipment when designing plant for new projects.The risk involved can be substantially minimised by testing equipment improvements using advanced computational models prior to implementation. Examples of application of Computational Fluid Dynamics (CFD) and Discrete Element Method (DEM) modelling to sampling, cyclones, conveyor transfers, classifiers, dust control, banana screens, comminution and smelt-reduction will be given to illustrate the benefi ts of such an approach. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

Various factors influence the exploration geologist or geochemist in his choice of.an analytical method for gold and other elements which may help him find the elusive gold deposit. One of the first decisions the geologist must make is the nature of sample media to collect for his survey. Needless to say there are many media available depending on the situation. These include rocks, soils, heavy mineral concentrates (from overburden drilling and panned concentrates), humus, vegetation, water, lake bottom sediments, stream sediments, etc. The choice of the sample media will depend to a large degree on the state of development of the particular project from grassroots to mine feasibility. The nature of the geological information required will affect which media and which analytical technique should be chosen for the analysis. Valid sampling from the initial sample collection, preparation and subsampling aspects may also help to determine which analytical procedure is best. Cost and turnaround time are of prime. importance to the explorationist, as it should be, however, these aspects should not be detached from receiving accurate and reliable results.

Jan 1, 1987

Just as Australia is part of the Pacific Rim, so the Pacific Rim should be viewed as part of the whole world. That applies in particular to that scarce commodity û money. There are five main factors of production in any mining development û mineralisation, materials, manpower, management and money. LetÆs focus on the upstream input û mineralisation, and the downstream input û money, especially in the area of communications. Unknown to many, the Competent Person reporting on Mineral Resources and Mineral Reserves has a direct and unavoidable impact on the companyÆs financial statements û the profit and loss account and balance sheet. With respect to reporting of the major asset of most mining companies û the resources/reserves û investors are getting a better deal now than at any time in memory as regards flow and adequacy of information. Australia has been a world leader in this regard. The outlook is for even more informative and useful reporting. The more rigorous reporting requirements for Exploration Results and Mineral Resources/Reserves, which have become a worldwide phenomenon over the last five years, will continue. This will be positive for the mining industry as a whole and for Australia in particular. However competition for the scarce investment dollar will also increase. Put simply, mining has many competitors, unconnected with mining, for the capture of the investment dollar. It behoves all participants to recognise that there are three investment factors which influence strongly the willingness of investors to put money into mining. These are Confidence, Credibility and Consistency. AustraliaÆs investment image stands high in these three respects, but the competition will continue to grow. AustraliaÆs lead must be maintained. However, some investment decisions should not necessarily be based on fundamental, quantifiable facors. Some of these are outlined.

Jan 1, 2004

The phrase "Total-Energy" has, during the past few years, become widely used to describe a wide range of very different operations. However, if accurately described they all have one basic factor in common - energy usage is optimised with the prime mover being powered by gas or oil to generate shaft horsepower and the products of combustion being put to some use. The item which distinguishes a Total Energy system from any other engine or turbine driven project is that orate pains are taken to utilize the waste heat, whether this be in the form of exhaust gases and/or engine jacket ling water. n areas where grid supplies of electricity are readily available, the economics of most projects undoubtedly hinge upon the successful application of waste heat. However, there has been a growing awareness of other benefits, such as reliability of supply, which can be incorporated into the system. In particular these factors sway managements of hospitals and companies with complex computer facilities to examine closely the feasibility of Total Energy, Consequently, in America for example, where many systems have proved themselves the list of applications is wide - shopping centres, apartment blocks, office buildings, airline terminals, universities, schools, motels. And these do not cover the industrial sectors where the range is wider. The total number in North America is now approximately 500 and this to some extent-speaks for itself. In Australia, the real work involved in carrying out feasibility studies for Total Energy is only just beginning. 'in some quarters, the concept is not well received in that it is too new. Therefore, a typical approach is to play safe and wait until some other company has proved its operation "under Australian conditions". This is certainly a realistic approach when considering something revolutionary but as far as Total Energy.is"concerned all the individual components and sometimes combinations, (engines, generators, boilers, air-conditioning units) have been in operation for many years. The only innovation is that they are now all being brought together under one roof. This should not be forgotten when the question "where can I see something like this operating?" is asked.

Jan 1, 1970

A universal grinding circuit model suitable for an arbitrary structure of flowsheet has been suggested. In this model classifiers and mills are described in a most general form. What puts the model in a class by itself is the automatic mass balancing in all streams of the circuit. In order to provide this a special classifier model is adopted. A previously published continuous steady state process model is used as a grinding model. Non-linearity of classifier model leads to a resultant circuit model which is equivalent to a non-linear integral equation. It complicates somewhat calculation algorithm in comparison to that of linear model, but provides a physically meaningful solution.

Jan 1, 1993

The metallurgical testwork program is generally the most important critical path item for the completion of a bankable feasibility study and hence can become the critical parameter for financing of potential mining projects. This paper presents generic detailed testwork programs suitable for bankable feasibility studies for a gold leaching and polymetallic flotation study. The design of the metallurgical testwork program for each of the two differing processes is discussed and the critical factors that effect the selection of the testwork programs are highlighted. The importance of the metallurgical testwork results in predicting the metal recoveries and cash flow prediction for the project is presented. The detail of the testwork programs costing is broken into activity based methods based on the laboratory and management hours/costs, such that generic rule of thumb costing guidelines can be generated. The scheduling, costing and importance of the metallurgical testwork program to process feasibility studies are discussed in this paper.

Jan 1, 2000

Before exploration programmes or minerals developments are formulated, a mining company ought to assess how capital can be returned if the project is successful. A fact not well appreciated by the minerals community is that it is often difficult to get money out of many Pacific Rim countries due to special foreign exchange controls or restrictions on dividend or capital repatriation. On top of this risk are factors such as creeping expropriation through administrative, fiscal, or corruption pressures; environmental regulations; terrorists; and organised labour and political activists. Political risk is much more than just expropriation or nationalisation.Political risk factors can make or break a project in many PacRim countries and just the cost of delays and negotiations can insidiously affect project economics. This unpalatable thought, however, can be readily addressed by either legal structuring e.g. offshore proceeds accounts, offset/back-to-back currency hedges, or political risk insurance for the equity as well as any subsequent project development debt.

Jan 1, 1990

By Jefferson CB

Adaptive optimisation is the adjustment of operating conditions to maintain optimum process performance as the feed quality varies. This strategy has the potential to be economic- ally better than the maintenance of a constant optimum performance with a blended feed. Application of the strategy is hindered by practical difficulties and economic risks. A computer simulation of leaching processes has been used to identify ore-process systems which have the greatest potential benefits from adaptive optimisation. They are systems with low value feed materials and a broad distribution of reactivities, in pro- cesses which are sensitive to the operating variable that is being manipulated (e.g. residence time). Improvements of up to 13% in throughput and 5% in the economic operating margin can be achieved. The results are sen- sitive to the precise model which is used for the process kinetics. It seems that the kinetics of the last few per cent to react are particularly relevant. A realistic situation has been identified where a synergistic inter- action occurs in blended feeds which makes adaptive optimisation disadvantageous.

Jan 1, 1984

Poorly designed sampling protocols generally result in high project risk by artificially increasing grade variability (ie the nugget effect). Sample collection, preparation and assay protocols that suit the ore type, together with QA/QC systems, will reduce this risk. All reporting codes (eg JORC, 2004) require the Competent Person to consider the quality and implication of sampling and assaying programs. High sampling errors beget higher project uncertainty; despite this fact, sampling does not receive the attention it deserves. The case studies presented show that many sampling issues frequently go unrecognised or unaddressed, resulting in poor project decisions during exploration through to feasibility and production. The overall conclusion is that correct sampling is critical to mining project success and that there is often a need for its optimisation.

Jan 1, 2007

We have been exploring for minerals in Australia for over 100 years and our methods are constantly improving - but why do we pros- pect? Is the effort justified? Obviously the main motive is economic gain. It is now and always has been but conditions are changing rapidly. Once it was the prospector who could cash the nugget. Then it was the syndicate, the small company, an amalgamation of small companies, the large company, the corporation; the multinational corporation - where do we go from there? Early there was personal satisfaction and excitement in out-door activity which gave scope for individual energy, hope and in some cases reward. There still remains the satisfaction, either individual or corporate that a mineral discovery creates new wealth and makes a contribution to the nation's well being. Parallel with developments has always been the growth of restraints on exploration, frequently out of phase with the current mineral developments - miners' rights, licences, titles, royalties, mining laws and regulations, taxation etc. As the operations have become more complex so the restraints have become more confining until it is now very necessary to question whether the chances of economic gain justify the risk and responsibility of mounting costly mineral exploration leading-to extensive capital development.

Jan 1, 1974