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An empirical kinetic model is discussed that enables the number of stages in a carbon-in-pulp plant and the amount of carbon in each stage to be calculated for any desired metallurgical performance. It is shown that a knowledge of the kinetics of gold extraction by activated carbon in each stage assists plant operators in the important' areas of process control and optimization. Factors such as mixing efficiency, concentration and distribution of carbon through the plant, bypassing of pulp through a stage, and carbon poisoning are examined. The resin-in-pulp process for the extraction of gold cyanide is also discussed, and the chemistry of absorption and elution on strong- and weak-base resins is examined. In addition, operating results from a small-scale resin-in-pulp pilot plant are presented, and various applications in which resin-in-pulp may be preferable to carbon-in-pulp are discussed.

Jan 1, 1982

Zircon is extensively used as moulding sand in the production of steel and high-duty iron castings. To achieve a satisfactory grade of zircon concentrate, the zircon particles may need ,to have surface coatings removed, as such coatings can hinder electrostatic and magnetic separation of zircon from associated minerals. Xn addition the presence of surface coatings on the zircon. particles can cause sinterins and fusion of the zircon to the east metal resulting in "burnt-on" sand or fritting of the casting. "Burnon" necessitates cleaning of the casting by grinding or chipping, which is expensive and results in loss of definition on the casting face.Hudson (1966) has pointed out ,that some coatings on mineral sands are lightly-adhering clays which can be removed quite readily by agitating the sands in water for a few minutes-thus their removal constitutesno problem. However, the heavy gingery coloured coating which adheres strongly to the surface of the particles in some deposits, and which has generally been considered to be a form of iron oxide (Baker, 1962; Hudson, 1966), cannot be removed effectively by attrition cleaning in water (Hudson, 1966). Such coatings limit the usefulness of these concentrates in the foundry industry.An investigation of strongly-adhering coatings on "ginger zircon" concentrates from the Yoganup deposit of Westralian Sands Ltd has shown that the stain consists of a cemented mixtvre of hydrated iron and aluminium oxides and kaolin minerals, and that it can be removed by a relatively low cost treatment.IDENTIFICATION OF THE STAIN BY XRDX-ray powder diffraction (XRD) patterns were obtained from small samples of stain scraped, individually, from the surface of hand-picked zircon and ilmenite crystals. These scrapings were mounted on quartz fibres and exposed to CoKa radiation in a 57 mm Debye camera. To avoid heavy fogging of the x-ray films, a substantial amount of the iron oxides was preferentially leached from the scrapings (before mounting) with an ammonium oxalate-oxalic acid solution (Rooksby, 1961). The residual material gave a fairly well resolved powder pattern (Table 1). A...

Jan 1, 1975

By R N. Lamb, A N. Buckley

Experiments have been carried out to establish whether time-of-flight secondary ion mass spectrometry (ToF-SIMS) is able to differentiate monolayer and multilayer coverage of thiol collectors on sulfide minerals. The systems investigated were those for which x-ray photoelectron spectroscopy is able to provide an independent determination of the extent of coverage, and included diethyldithiophosphate (DTP) and 2-mercaptobenzothiazole (MBT) on chalcocite, DTP on Ag2+MS prepared by sulfidising metallic silver, and isobutyl xanthate (BX) and MBT on galena. For monolayer adsorption of MBT on chalcocite, peaks from MBTû but not Cu(MBT)û ions were evident. For multilayer coverage, Cu(MBT)2û ions were clearly present, notwithstanding the fact that other data had identified the principal multilayer species as Cu(MBT). For adsorbed DTP on copper and silver sulfides, DTPû and metal(DTP)Hû peaks were observed for monolayer and multilayer coverage. Although the multilayer species was expected to be predominantly metal(DTP), metal(DTP)2û ions were evident for multilayer (but not monolayer) coverage. For the PbS/BX system, intact Pb(BX)2 or Pb(OH)BX ions were not detected for multilayer coverage, although Pb-containing ions heavier than PbBX were. Indeed, for all the systems studied, ToF-SIMS was able to differentiate monolayer from multilayer coverage. In general, however, the SIMS evidence alone might not be sufficiently definitive to effect the differentiation. In the case of collector adsorption on copper and silver sulfides, if the multilayer species detected had been the metal monothiolate only, and had not involved the formation of some metal dithiolate, then ToF-SIMS might not have been able to provide an unequivocal differentiation of the two coverage conditions.

Jan 1, 2005

The Gj0vik Olympic Mountain Hall is the world's largest underground cavern for public use and was created primarily to facilitate the ice hockey tournaments for the 1994 winter Olympics in Norway. The cavern has a span of 61 m, is 91 m long and is 25 m high. Ordinarily, rock caverns have a span width of 15 to 25 m, however, temporary mining caverns of up to 60 m have been excavated and natural caves with even greater dimensions occur. The Gj0vik Olympic Mountain Hall is unique as it is for public use with a capacity for 5800 spectators. Blasting was conducted with a high production rate at normal costs due to detailed planning and strict supervision of each round. The initiation system and vibration monitors were the main tools to control vibration levels and to facilitate a high production rate. It was of utmost importance that the rock remaining in the roofs and walls was of high quality after blasting to avoid rock fall, rock slides and excessive maintenance work.

Jan 1, 1995

By V Novoselov, R Sabirov

Flotation processing technology of water-soluble minerals has made it possible to realise, since the 1960s, the wide scale industrial processing of potash and potassium-magnesium ores (about 200 million tonnes per year) as well as to create the multi-tonnage worldwide production of sylvite (KCl) for industrial and agricultural application. In this paper the particularities of the effect of reagents (blinders, collectors and frothers) during cation flotation in saturated saline solutions are outlined. New reagent modes for activating the effects of alkylamines during the flotation of KCl and the perfecting of technological flow sheets for processing potassium ore have been developed. The results of research on the reverse flotation of carnallite ore, with the help of alkylmorpholine û a new developing technology for benefication carnallite as raw material for the production of metal magnesium and fertilisers are listed. Examples are given of the industrial applications of processed reagent modes at potash flotation factories in Russia.

Jan 1, 2005

By M Kuruppu

The paper explores the sustainability of the Australian mining industry, and the potential for application of a substitute fuel into existing mining operations. This alternative fuel biodiesel is produced from biological oils and not from refined hydrocarbons like the transport fuel diesel (petrodiesel). The fuel is compatible with all current diesel equipment with little to no modification and has many superior properties. As biodiesel is derived from biological sources it is æcarbon neutralÆ meaning there is no net carbon addition to the atmosphere when the fuel is burned. The current fuel, petrodiesel releases long stored carbon dioxide (CO2) and is of concern to Australian government targets which seek to reduce these emissions. The mining industryÆs unique reliance on petrodiesel is of particular interest when assessing the substitution of biodiesel into underground and open cut operations. The underground benefits of biodiesel see a reduction in the noxious emissions of carbon monoxide and diesel particulate matter, both contaminants which require extensive diluting ventilation to ensure safe levels. As biodiesel is both safer to store due to its higher flash point and produces less exhaust emissions, its occupational health and safety benefits in underground mines is clear. The use of biodiesel in open cut mines benefits the environmental sustainability aspects of the project. The formulation of national targets relating to carbon dioxide emission reductions promotes any measure to reduce CO2 within the mining environment. As the diesel engine is one of the least emission efficient (kWh/tonne CO2) energy sources on-site, its potential for reduction in CO2 at minimal cost is the greatest. By substituting the fuel, significant quantities of site emissions are reduced, thereby achieving the goals of improved site sustainability and the governmentÆs targets to reduce emissions. This aspect of gauging mutually beneficial relationship regarding government interests and mining industry profitability is the underlying outcome for this paper.

Jan 1, 2009

By B Ellis

Brunswick Mine is one of the largest underground zinc/lead mines in Canada, producing 3.4 million tones of ore annually. As mining activities advance to deeper levels, ground pressure also becomes greater. To cope with the highly stressed ground, the mine has taken some strategic measures to ensure the targeted production level. Such measures include the implementation of a pastefill system and transferring the mining method from primary/secondary stoping to pillarless pyramid stoping. With the pillarless mining method, stope sizes become smaller and the number of active stopes is also less than before. In addition, mining sequence and cycle time have to be strictly followed according to production schedule. The blasting project described in this paper tackles one of the steps in the mining cycle aimed at shortening the blasting cycle time in a stope. Furthermore, this project was conducted and managed with the Six Sigma initiative in Noranda which was implemented in the fall of 1999. Like a typical process review, the blasting operation was examined by breaking it down into many steps that can be quantified and measured. Each activity was then correlated with different factors associated with blast design as well as blast operations underground. It was found that the utilisation of voids plays a key role in the blasting cycle time. With improved void utilisation ratio, blasting cycle time has been reduced from an average of 12 shifts to ten shifts per stope. This improvement translates into approximately 180 000 tonnes of ore being blasted without any increase in manpower. This paper presents the technical aspects of the study, as well as some operational issues and improvements made during the project.

Jan 1, 2001

By M Henderson, M Hudyma

Mining-induced seismicity at Junction Gold Mine became a serious operational problem in the late-1990s. Assessing the local seismic hazard is an important step in assessing the risk associated with potential rockbursting. This paper discusses the qualitative and quantitative means of assessing seismic hazard used at Junction. In qualitative hazard assessment, the role of the primary factors contributing to mining-induced seismicity and rockbursting are identified. These factors include: rock mass properties, geological structures, mine development, and stoping. A qualitative seismic hazard map has been developed considering these factors. In quantitative hazard assessment, seismic source parameters from an Integrated Seismic System are used to assess seismic hazard. The seismic source parameters found to be relevant to seismic hazard assessment at Junction are discussed.

Jan 1, 2002

By B Morey, J Gordon, P Mackenzie

Mount Tom Price Mine is peerless amongst Rio Tinto iron ore resources around the world. It has provided Hamersley Iron with premium quality, high lump yield haematite ore over the last four decades. The Brockman type bedded ore, containing bands of haematite and shale of varying thicknesses has been traditionally bulk mined to either high-grade or low-grade based on alumina cut-off grades. As open pit mining has progressed deeper into the orebody approaching the keels of the megastructure, increased structural complexity, chemical and physical variations in the ore, unfavourable ore presentation and reduced blending options have become an issue for grade control and may have serious impacts on product stockpiles. The grade blocks and boundaries must be accurately defined according to geological contacts and where identified, selective mining may be applied. Therefore in-pit geological mapping is the definite and ultimate guide to achieve target grades and grade predictions. Under this scenario, it is absolutely vital that the mine geology team ensures this geological knowledge is passed onto the related departments including mining crews as well as to the short- and long-term planners.

Jan 1, 2002

By N Takamatsu

The environments surrounding the iron and steel industry have changed greatly in recent years. Reported in this paper are the technologies adopted by the Japanese iron and steel industry to fititself to change in global steel demands, degradation of iron ore and coal, prolonging service life of the facilities and requirements of energy saving. In addition, innovative technologies for CO2 emission control in iron making processes are also discussed.

Jul 11, 2011

By Kuganathan K, Potvin Y

Enterprise Mine at Mount Isa is to expand ore production from the current 1.4 to 3.5 mtpa by mining the 3500 Orebody, from which production is scheduled to start in February 1998 making this the deepest underground mine in Australia with its lowest mining horizon at nearly 1.6 km below surface. The following fill requirements were defined for the 3500 Orebody during the feasibility study: 1. a minimum filling rate of 250 ma/h, 2. a curing time of 28 days, and 3. minimum free fill water. This paper mainly describes the investigation of high density and paste fills for the 3500 Orebody. The investigation covered all the key issues relating to fill option selection, including design criteria, material supply and demand assessment, drainage modelling, tailing dewatering method, mix design and a pump loop test. Results of the investigation indicate that both high density fill and paste fill are technically feasible. The investigation has led to the selection of a blended tailing paste for the 3500 Orebody as the paste option has significant advantages over high density fill in stope filling rates and fill reticulation. The blended tailing for paste fill is finer than Isa deslimed tailing but coarser than full plant tailing. The paste fill selected has minimum binder and tailing dewatering requirements while a relatively high filling rate is achieved.

Jan 1, 1998

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

Precipitation of inorganic compounds or metals from aqueous solutions can either be physical (crystallisation) or chemical in nature. Chemical processes are varied; they may be due to hydrolytic action, due to ionic interaction, or due to reduction (ie transfer of electrons). Transfer of electrons in reduction processes may take place homogeneously or heterogeneously. In the first case it may be ionic or nonionic in nature. Heterogeneous processes may be electrochemical or electrolytic. Examples of interest to hydrometallurgy are given.

Jan 1, 1993

By Robinson BW, Walker RK

Using a new highly stable automated electron microprobe analyser, detection limits for gold in arsenopyrite have been improved. Using the AuLA emission tine at 40kV and 500nA, a limit of approximately 10gpt is attained in 10- lSmins. Some unusual features of the background need to be taken into account. Several ores containing different levels of gold in arsenopyrite have been examined, and it has been shown that gold is not evenly distributed between grains (some may contain more than 1%, invisible optically), and that the grains containing gold are often zoned. Gold may be released from the arsenopy rite by weathering or by heating in an inert or slightly oxidising atmosphere.

Jan 1, 1989

In Australia 'there are hidden deposits of gold, copper, tin, lead and zinc which can be found by drilling at reasonable expense in view of the imp9rtance of the objectives. Exploration of the prospects in mind would mean about a million feet of drilling. The purpose of this paper is to outline, in a technical way, some of the geological thinking that has been given to this matter. To do this, it is necessary to unify the wider ranging thoughts into some sort of coherent perspective and also into some sort of logical sequence. This will be done by treating first the geological subject material which is in fact, at the foundation of the exploratory scheme. With this base, the argument will be continued through a sequence of prospect thinking and brought to a conclusion in regard to the practical employment of geology in the drilling planning. In this knitting together of ideas, the discussion will be given substance by welding into the argument the reasoning that has been applied to the Cobar prospect. The New Occidental Gold-Mines are operating three mines at Cobar, and the writer is indebted to the Company for allowing the reference to be made. It is intended, as opportunity permits, to furnish further examples in later publications.FOUNDATION OF EXPLORATIONThe deposits under consideration are derived from igneous rocks, chiefly granite or porphyry. In and following the emplacement of the intrusives, the rocks have been...

Jan 1, 1946

Eleven years ago I addressed delegates to the Whyalla Meeting of this Institute on the subjects 'Oil in Australia?' -- a title which was followed by a large question mark.My purpose at that time, which was before Rough Range, was to interest members of this Institute in the possibility of oil in this country because I considered that exploration for mineralwealth was our concern.I doubt if I made much impression.but.I recall that the Chairman at that Meeting, Mr Ian McLennan, asked me pointedly to name the areas I-would select and I nominated the Northwest of Western Australia,'Gippsland and the Roma District

Jan 1, 1962

Geophysics is playing an increasingly important role in the exploration industry. In the soft rock scene the application of seismic techniques is basically mandatory prior to any drilling program. Simply, this is because, in a majority of situations, the seismic method is ideally suited to mapping accurately relatively flat lying strata and displaying structures that may host oil or gas. It is worth stressing that seismic methods do not delineate oil or gas but they map well in two or three dimensions. In the base metal arena, geophysical methods used are generally focussed on direct detection methods with the mapping application not often used except in potential fields (magnetics and gravity). The success rate in the last decade has not been good but this does not only apply to the application of geophysics; it really applies across the board of exploration techniques. Both geological and geochemical exploration have not had a success rate commensurate with the funds injected. Basically in the last ten years we have failed as explorers! As explorers we have been negligent in mapping. As geoscientists we have let the basic mapping and observation skills diminish û the old adage æboots on the groundÆ is still applicable but are we doing enough of it? The answer is clearly no. As explorers the huge burden of bureaucracy, eg Government Acts û local, state and federal, safety compliance, environmental compliance, etc has reduced the ægeologicalÆ time dramatically. This has culminated in an over-reliance on quick fix solutions, eg spot the bump geophysics or geochemistry. This obviously simplistic scenario is arguable but there is no doubt in the geoscientific areas we have failed in the last decade to provide adequate geoscientific maps to assist in exploration. This failure could partially be responsible for the current demise of the industry resulting in a reduction in exploration dollars and, hence, people. This trend is seen acutely in the geophysical area where the head count in comparison with the geological fraternity is low. Other trends during this downturn are inevitable as explorers maximise the use of the dollar in exploration and diminish spending on advances in geophysics. Improvements are being seen however in geophysical equipment, although it is considered that the main improvement will be in the interpretation of data. Specifically, the trend will be towards integrating geophysical data into geological, geochemical and spatial data sets producing quality interpretation and providing low risk drill targets. Examples of the current trends in hardware and future directions are discussed below. In interpretive schemes there are very few examples of integrated interpretation but the possible trends will be discussed with limited examples.

Jan 1, 2000

There are two main areas of application of geology in quarrying: (i) In regional planning for industrial mineral requirements.(ii) In direct quarry management. The regional planning requirement has recently become more evident because of greatly increased land demand conflicts around cities. The direct quarry involvement is a reflection of both the economy and the greatly increased sophistication of the quarry industry. Here, professional planning and development expertise by a geologist is required, to ensure continued supply of raw materials at the best price to the consumer with sufficient profit to the producer. Today, geological insurance safeguards capital investment in plant and assures economical development plans.

Jan 1, 1978

Although most N.S.W. coal mines contain large amounts of combustible materials such as coal and timber, the introduction of mechanisation has extended the range of combustible materials now found underground. The role of combustible material in a fire is not clearly understood and as a result the assessment of these materials for flammability by small and large scale tests is doubtful. Extensive research has been carried out on the toxic and irritating gases evolved during the combustion of plastics. However, most autopsies report death due to carbon monoxide inhalation because the combined toxicity of smoke and fire gases is unknown.

Jan 1, 1981

By Twemlow GL

The accounting profession in Australia and overseas has taken up the responsibility of setting standards specifically relating to the minerals and energy industries. Australia led the way with AAS7 Accounting for the Extractive Industries. This statement was issued in 1976 and amended 1977..It largely deals with accounting for preproduction expenditure and uses the term "economically recoverable reserves". It does not require disclosure of reserve quantities or values in balance sheets or as supplementary information in financial statements. The United States accounting profession in 1982 finally resolved an accounting standard in the same area as AAS7-SFAS69 Disclosures About Oil and Gas Producing Activities. It applies only to oil and gas producers, but has extensive disclosure requirements, including proved oil and gas reserve quantities. Current developments indicate that Great Britain is about to follow the US example. At this time in Australia, AAS7 or some other statement relating to the extractive industries has not been issued as an approved accounting standard by the ASRB. Standards issued by the ASRB are binding in law.

Jan 1, 1987