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By Chen B

In recent years great efforts have been made in the optimisation of ball mill operation. This paper describes a methodology developed for modelling and optimising the steady-state grinding process. Thirteen basic similarity numbers of the process are derived. Based on these similarity numbers, we build a group of mathematical models which give a full description of the relation between dependent and independent variables. The parameter estimation and multi-objective optimisation of the grinding process have been done using these models, and validated with experiments in a continuous laboratory-scale ball mill.

Jan 1, 1993

By A Mortazavi, M Akhmedya

Mining is recognised as being one of the most dangerous industries in the world due to the difficult working conditions. Working in such hazardous circumstances in an underground mine often results in a variety of accidents. The working conditions at Kazakhstan’s underground mines have deteriorated owing to a lack of a risk-reduction plan and methodology. This paper evaluates different underground mines in Kazakhstan and demonstrates the employed mining method and the observed failure modes. Risk assessment has long been recognised as a valuable technique for preventing accidents. In the underground mining sector, risk assessment tools play an important role in avoiding work-related accidents. However, geotechnical uncertainty is a significant source of severe incidents like stress-induced roof collapse, wedge failure, seismicity etc, which result in human and financial losses. A geotechnical risk assessment performed early in the mine design process might assist justify a different mine design component, such as different support systems for a dangerous location within the mine openings during mining. The goal of this research is to create a damage/failure database aiming at the development of a geomechanical risk assessment methodology. This work identifies a thematic structure linked to risk assessment and management for the examined Kazakhstan mining sector. As part of the developed database, the dominant modes of failure within the Kazakhstan underground mining conditions were investigated. The study will provide opportunities to establish future research objectives for Kazakhstan’s mining industry where there are significant gaps between state-of-the-art research and mining operations in practice.

Nov 29, 2022

The introduction of legal certification of mine managers is a matter of history. It was introduced as part of legislation for mine safety. It has been said that such legislat- ion was written in blood. Like all legislation this legislation is divided into three sections; commands, obligations and sanctions. While legislation in all States on this subject is similar, the differences are great enough to have prompted the preparation of a Uniform Code by the Annual Conference of Chief Inspectors of Mines. This Uniform Code has not been adopted fully by any State to date. Legal certification of mine managers has made managers more aware of the requirements of the legislation covering their industry, legislation that reads as a summary on past accidents and methods of preventing them. While budding managers spend considerable' time in their early years in the preparation for certification, history has shown that the industry has benefited from their efforts. A better knowledge of the safety acts by the managers has produced safer operations, and a higher standard of management has raised the technical standards of mining operations to a stage where Australia can be proud.

Jan 1, 1980

By R Cox, S Pandey

The coal seam gas (CSG) industry is expanding rapidly in the Surat and Bowen basins. CSG production involves pumping water from the coal seams to release the gas adsorbed to coal particles. The reduction in water pressure in the coal seams will cause some reductions in water pressure in overlying and underlying aquifers because there will always be some interconnectivity between the formations. The Surat Basin is a sub-basin of the Great Artesian Basin, which contains aquifers of high economic, environmental and cultural value. The Condamine Alluvium is also an important water resource, which overlies parts of the eastern margin of the Surat Basin.Under the Queensland (Qld) regulatory framework, an area of intensive CSG development involving multiple CSG operators can be declared to be a cumulative management area. For such areas the Office of Groundwater Impact Assessment develops assessments of future impacts on aquifer water pressures and develops and manages arrangements. The results are published in underground water impact reports.The Surat underground water impact report (QWC, 2012) was approved in December 2012. This paper summarises the place of the report in the Queensland regulatory framework, the content of the report and progress in its implementation.CITATION:Cox, R and Pandey, S, 2013. Managing groundwater impacts in the Surat Basin, in Proceedings Water in Mining 2013 , pp 169-174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

The development of the Ballarat goldfield and of the city of Ballarat are a significant part of the history of the Australian mining industry. Important developments in technology, legislation and labour relations made their first Australian appearance in Ballarat. The growth of the city and its survival after the closure of the mines provide an interesting case study in the benefits flowing from a vigorous mining operation. The failure of the mines can be attributed to rising costs of materials and labour and declining manpower productivity at a time when the price of gold was not free to respond to changing market conditions. The curtailment of exploration programs and increasing labour unrest resulted from this situation, and made the closure of mines inevitable.

Jan 1, 1982

This paper looks at the various stages of development of open stope drilling techniques. Due to the structural nature of the orebodies mined by open stoping it has been necessary to review mining methods. In-the-hole hammer drilling proved to be the solution to many problems encountered in horizontal percussion drilling.

Jan 1, 1977

By Morandini AF, Occella E, Clerici C, Mancini R

This contribution presents the first results of an experimental research aimed at finding an unified description of the first stages of a rock comminution process. With reference to the case of the jaw crushers and to the specific subject of the comminution law, the tests reviewed and analysed in this contribution have been carried out, at a laboratory scale, on five different materials (limestones, quartzite, serpentinite) at different reduction ratios and feed rates, and accurately recording both total power and idle running power. The analysis of the results has shown that: ò the grain size distribution of the products complies with a modified form of the Rosin-Rammler equation, already found to be well suited to representing the grain size distribution of blasted rock in previous works by the authors; ò observed trends of the consumed power at increasing reduction ratios is steeper than predicted by the classical Rittinger, Kick and Bond laws, Rittinger law representing however a closer approximation of the experimental results; and ò a more accurate description of the experimental results is provided by a modified form of the Rittinger law. Accuracy of the semi-empirical expression has been found to be usually better than ten per cent by comparing actual results with expected Results.

Jan 1, 1993

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

Access to land for exploration, development and mining purposes is extremely critical to the viability of the mining industry and subsequently the well being of society.The mining industry has been subject to environmental controls and considerations for the past 20 years. Today there is greater land use competition and more debate as to its use. To retain reasonable access the mining industry must comply with the rules and regulations by which it is governed.A new set of rules and regulations have been approved for use in Queensland, known as the Mineral Resources Act 1989. This Act clearly outlines the titles available and the requirements to obtain access.There are three main titles of interest to mining companies. These are an Exploration Permit, Mineral Development Licence and a Mining Lease.The Exploration Permit (EP) is for exploration purposes. Applications for EP's are assessed on their content and past performances. An EP is granted subject to a security deposit and conditions. Prior to entry the EP holder is required to inform the land owner of the proposed activities and times of entry.

Jan 1, 1990

Kinetics of bubble-particle interaction, surface hydrophobicity and interfacial phenomena in sulfide mineral flotation are discussed in this paper. Results of the measurements of a bubble and mineral induction time (IT) and detachment force (DF), vacuum of bubble evolution (VE) and mineral floatability are discussed for pyrite, galena, chalcocite and chalcopyrite. Natural wetting and wetting induced by xanthates with different lengths of alkyl chains are examined. Experiments show the existence of several maxima of hydrophobicity on dependences of pH and electrochemical potential. These maxima are attributed as the reflection of mineral surface heterogeneity due to xanthate adsorption and the presence of cationic and anionic centres with uncompensated positive and negative charges. These charges can be neutralised by both regulation pH and applied potential. The aim of this paper is to evaluate a thickness of the rupturing film and to estimate how long the bubble-mineral interactions are according to the experimental values of IT, in order to develop a procedure for comparing of the results of DF and atomic force measurements in the same dimensionality, and to compare the results of the experimental studies on the wettability of sulfides with those predicted by the models of physics of capillarity.

Jan 1, 2005

By D Matthews

With a brownfield project comes control integration challenges. The Khumani Iron Ore Mine’s second phase expansion posed a number of challenges as there was substantial brownfields work conducted. The fi rst phase was the compilation of the modifi ed process functional specifications for the project. The second phase was an audit on all of the operational sequences; this included a comparison between the SCADA sequences, sequential starts analysed from the historian data (with the potential for improvements made by the plant operators in manual start-ups) and what was proposed in the process functional specification. Differences, inclusions and missing equipment were highlighted. The third phase was the comparison of interlocking and control in the PLC with the updated process functional specification; this was done during the coding process. Running parallel to the three phases was the SCADA integration; tie-ins to the existing SCADA were conducted on maintenance days and shutdowns, in many instances with ‘dummy’ equipment to get the operational staff accustomed to the new interface. This paper details each of the phases, the success of this methodology as well as the pitfalls experienced.

Jul 11, 2011

By D Stephenson, N R. Steward

“TerraFlowingTM” is a dewatering process that addresses both the value proposition of Tailings as a Resource™, and the safe storage of tailings. “TerraFlowingTM” incorporates two stages of cyclone dewatering followed by centrifugation of the final dilute tailings stream. In this process three dewatered tailings streams are produced; a primary cyclone underflow, a secondary cyclone underflow and a centrifuge pulp. These three streams can be combined, or used, in various configurations to achieve different outcomes. The ability to vary the cyclone and centrifuge operations and configuration enables this process to deal with tailings feed variations in particle size distribution and mineralogy and deliver consistency, or design variations, in particle size distribution, tailings solids concentrations and recoveries. Water recovery can be up to 85% of the total water in the tailings with a stackable final tailings product achieved if the three tailings streams are combined in the maximum solids concentration configuration. The primary cyclone can be operated to deliver a particle size distribution suitable for tailings storage facility embankment construction or alternatives such as concrete structures or shotcrete for support. The secondary cyclone underflow and centrifuge pulp is suitable for beaching deposition within the tailings storage facility.

Jul 1, 2021

Mine Dewatering for reoccupation of a flooded mine requires rehabilitation and recommissioning of shaft and sane level functions to provide safe efficient access, services and logistics, as well as securing connections with all exposed workings. The objective is the earliest secure reoccupation of the target depth horizon for minimum water pumping, consistent with an appropriate investment and optimum schedule of operating inputs to the dewatering, redevelopment, services and consolidation processes. Strategy must focus on recommissioning of relevant functions in the shaft and at stage pumping horizons, advance of logistics close to pumping and rehabilitation, management of the secured exposed workings. The progress must be systematic, sustained and integrated, and must be secured against risk and uncertainty. There must be a strategic capability to respond effectively, and manage interruptions to processes, conditions requiring higher or different resources, and contingencies which affect schedule, budget or risk profile for the continuing programme. Planning must aim to reduce or contain risk or uncertainty elements and contingencies, limit interruption frequency and severity, identify and provide the capability for efficient responses. It is appropriate to model and simulate the reoccupation analogous to a mine initial development production programme. Only minor changes to relationships and relativities of models for Capital works, Operations (Production and Development) and Services/Logistics are needed but the model for management of workings is more relevant than that for depleted workings in an operating mine because of the water and other transfers. An important difference is the unsteady state of operations which requires probabilistic modelling of availability and utilization of equipment and processes.

Jan 1, 1988

By Paine GG

The Kidston Gold Mine commenced mining in 1984 and current annual production is 12 million tonnes, increasing in 1990 to 18 million tonnes. Mill throughout per year is 4 million tonnes with the balance of material being waste. The operation is a conventional hard rock open pit truck and shovel operation mining 12 metre benches. Buffer blasting is utilized to minimize post blast movement of the broken rock to maintain grade control.

Jan 1, 1988

Automatic sampling and weighing of copper sulphide concentrate produced on Bougainville Island (PNG) is described. Contained metal weights gave satisfactory agreement with buyer's results after the introduction of polyethylene lined sealed aluminium foil bags for transport and storage of assay samples. Paper bags used previously for this purpose permitted oxidation of the sulphide concentrate and thus caused lower assay values.

Jan 1, 1976

By McGill RA

The Ranger Uranium Mine is surrounded by a World Heritage National Park. The strict environmental controls under which the mine operates are based on scientific and social requirements. Release of non-process storm runoff water to the Magela Creek during flood discharge and under controlled conditions has been identified as Best Practicable Technology for the operation of the water management system. Social and political factors have limited this release to a wet season with an Annual Exceedance Probability of one in ten. The first-generation trigger mechanism was based on a percentile analysis of monthly rainfall. The second-generation trigger is based on cumulative monthly volume increase in the retention ponds and is considered to be more applicable to the operation of the mine water management system.

Jan 1, 1988

The treatment of nickel ores and concentrates and the subsequent processing to recover separate products of nickel and cobalt is one of the major interests at present in the mining industry. The increasing demand for nickel, and more recently also cobalt, has led to increased exploration for ore sources. Major discoveries have resulted in Canada and Australia. These deposits, as well as others already known, are presently being developed and the process technology tested and evaluated for applicability to the different mineralogical types - mainly sulphide, arsenide and oxide laterites. Concentrates may be treated by either hydro- or pyrometallurgical processes, while the nickel laterites are best suited to hydrometallurgical processing. However, if hydrometallurgy is used, once the ore or concentrate is leached the resultant solutions are then amenable to similar separation technologies for purification and recovery of high purity nickel and cobalt products. Solvent extraction, together with other separation processes such as precipitation, can produce high purity solutions of nickel and cobalt. The final products of these solutions may be nickel and cobalt cathodes, metal powders precipitates or salts, depending on the final process of electrowinning, hydrogen reduction, precipitation, or crystallisation Respectively.

Jan 1, 1996

It is no longer adequate when starting a new mine to simply select the best equipment. Today's competitive international commodity markets demand superior efficiency which requires systematic involvement of people in continual improvement of production and commercial processes. True Total Quality of Management (True TQM) principles provide an operating philosophy for maximising productivity and minimising unit costs of output. The presentation will show the practical and successful use of these principles. This paper will introduce the case study and provide background material on True TQM.

Jan 1, 1995

By Floyd JM

Conventional smelting reactor systems were designed to recover only one main element from their feedstocks. They did not possess sufficient flexibility to allow optimisation of co-production of multiple values from a complex feed.New reactors such as Sirosmelt and Top Blown Rotary Converters are providing new possibilities for making separation between components and this is of great significance for the complex feeds which are becoming prevalent in the metal extraction industry.Process routes using chemical procedures which take advantage of the flexibility of these reactors will be discussed in relation to a number of possible feedstocks.

Jan 1, 1985

By K Myers

Since the mid-1990s, the Chino Mine Facility (Chino) located near Silver City, New Mexico has been developing a closure plan with financial assurance to protect water quality, as required by State regulations. In February 2002, Chino and the New Mexico Environment Department (NMED) reached agreement on a closure plan; a closure cost amount of approximately $US 394 million ($A 591 million) was finalised in April 2003. Both the New Mexico Water Quality Act Regulations (1977) and the New Mexico Mining Act Regulations (1993) guided development of the closure plan and financial assurance amount. The process incorporated many years of correspondence, studies, negotiations and administrative hearings. The major technical issues focused on regrading slopes of the leach ore stockpiles and waste rock piles; cover systems; water treatment systems; and abatement of ground water contamination. The proposed financial assurance amount covers all closure costs and provides for perpetual water treatment.

Jan 1, 2003