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Production of oic at BHP Minerals Pty Ltd's Cannington Mine commenced in May 1997. The initial sloping blocks at the [nine are located in the upper part of the Footwall Lead lode, and the Hangingwall Lead and Glenholme Breccia lodes. This paper discusses the geological investigations, interpretation and modelling that was undertaken for the Footwall Lead lode production block at Cannington Mine, as well as providing a basic geological introduction to the Cannington deposit.

Jan 1, 1997

By Fisher WJ

The'treatment of the South Alligator valley uranium ores passed through three phases dictated by economic circumstances during the years 1956- 640 In the first phase high grade ores were treated by hand sorting and wet gravity separation for recovery of high grade concentrate to meet a United States Atomic Energy Commission (U.S.A.E.C.) contract for plus 50 per cent pitchblende concentrates. Secondly tailings from the gravity plant and some high grade ores were trucked to Rum Jungle and sold to the Australian Atomic Energy Comm- ission (A.A.E.C.). Thirdly solvent extraction plants were built at Moline (previously Northern Hercules) by United Uranium N.L. (UOU.N.L.) and at the South Alligator River by South Alligator Uranium N.L. (SOA.U.N.L.). These were the first solvent extraction plants designed in Australia, as earlier plants used the ion exchange process for recovery of uranium oxide. The plants were small, indeed the S.A.U.N.L. 15 ton per day plant was possibly the smallest commercial plant known, but they operated efficiently with good recoveries, and were placed on a care and maintenance'òbasis when contracts were filled. Sulphuric acid was supplied in bulk to both plants by the A.A.E.C. from the 30 ton a day acid plant at Rum Jungle. Gold was recovered as a by product of uranium ore from the Moline plant.

Jan 1, 1968

By Just G. D

The results of a geostatistical analysis of geochemical data obtained from field measurements are described in the paper. Q values derived from seismic signal rise times for different travel paths in the rock masses were used in the study. Cross-hole seismic measurements made at surface and underground sites formed the basis for the work. Geostatistical estimation of average l/Q values for area of the rock were compared with geological interpretions of rock type distributions. Reasonable correlations were obtained between the two methods of rock quality estimation.

Jan 1, 1988

By M Yahyaei, M S. Powell

Mineral processing plants have become large and complex, generally through progressive expansions. Addition of a pre-crushing stage to conventional Semi-Autogenous-Grinding (SAG) and ball mill - crushing (SABC) circuits has introduced a complex materials handling system coping with +200 mm particles. Application of High Pressure Grinding Rolls (HPGRs) and implementing hybrid comminution circuits (ie, HPGR-SAG mill) requires proactive control of the feed size distribution to each unit. Application of Vertical Tower Mills (VTMs) and other fine grinding equipment to achieve a finer grind size, while maintaining the throughput, requires splitting the feed evenly between parallel units. Many of the conventional comminution circuits (ie, staged crushing and screening followed by staged ball milling) must deal with the transition from open pit ore, which is generally altered and soft, to underground ore, which is intact and hard, requiring existing crushers to produce a finer product to unload the ball mills.This paper presents common process improvement opportunities which have been identified during a number plant process reviews conducted by the authors in Australian and international operations. The operation of comminution circuits to known and accepted standards, which is explained in this paper, could improve the performance of circuits by between 5 and 10 per cent, generally at no capital cost and often at a lower operating cost. The performance improvement can be realised as throughput increase, a finer product size, or reduced operating costs (ie, energy saving, low maintenance, less consumables).Process optimisation opportunities presented in this paper include: enhancing materials handling and storage to avoid segregation; standard operation of screens to reduce misplaced materials; proper feeding arrangement and control of crushers to increase their utilisation; preparing proper feed for SAG mills to reduce grind size; splitting the feed evenly between parallel equipment to improve utilisation, and controlling operation of classification units to improve energy utilisation.CITATION:Yahyaei, M and Powell, M S, 2018. Production improvement opportunities in comminution circuits, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 233–248 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By I D. Hair

A numerical groundwater model was used to predict the nature of interactions between heavy mineral sands mining operations and the groundwater regime at North Stradbroke Island, Southeast Queensland. North Stradbroke Island is formed mainly of massive vegetated Cainozoic aged dune sands. Since the 1950s, a number of operations have mined rutile, zircon and ilmenite on North Stradbroke Island. In such mining operations, a dredge and an associated processing plant are floated in a pond either above or below the prime groundwater table The numerical model was based on the North Stradbroke Island Groundwater Management Model, developed in 2001 by the Department of Natural Resources and Mines (NR&M). This model was constructed using the modular, cell-centred, finite-difference groundwater flow model, MODFLOW, developed by the United States Geological Survey (USGS). The NR&M model was refined to improve model resolution and detail for simulating dredge mine paths. Of particular interest were: water table fluctuations induced by mining for the identification of slope stability risk; the optimisation of sand spear arrays supplying mine make-up water requirements; inflow and outflow rates to the dredge pond for overall mine water balance; and interactions with Eighteen Mile Swamp and water supply bores controlled by the Redland Shire Council (RSC). Depending on the water level in the dredge pond compared with the surrounding groundwater table, water either flows out of the dredge pond into the groundwater regime or from the groundwater system into the dredge pond. The MODFLOW river package (RIV) was utilised for the modelling study. Dredge pond movement was simulated using specialised software developed by Watermark Numerical Computing (WNC) to interpolate pond positions and map the dredge path to the model grid both spatially and temporally. As tailings placement affects the groundwater system through increased recharge, the MODFLOW recharge package (RCH) was utilised to simulate different recharge efficiencies. Long-term model predictions were made for the period from July 2002 to May 2021. Results of the modelling showed that exchanges of flow between mining operations and the groundwater regime could be effectively managed. The study provided valuable information which was used to develop an appropriate mine water management plan.

Jan 1, 2003

The geographical and geological situations of the two mineral sand deposits currently being mined by Western Titanium Limited and the mining methods in use are briefly described. Production scheduling involving the ability to vary the proportions of the major minerals produced, together with maintaining a constant feed grade to the wet concentrator has been assuming greater importance to the company in recent years as the relative value of these minerals, due mainly to technological advances and environmental considerations, is subject to significant and rapid change. Manual calculation, even using a programmable calculator, became a trade-off between man hours and data usage. Schedules were updated infrequently and only a fraction of the avail- able data was used. In July 1975 a Data General NOVA 2/10 minicomputer with a 24K word core and three cassette drives was purchased. A suite of programmes was developed using BASIC to assist in production scheduling and these were opera- tional early in 1976.

Jan 1, 1977

By Moore R

An intensive safety campaign at Mount Isa Mines Limited from 1956 to 1966 saw the lost time accident frequency rate fall to half its original level. A review of the safety programme was carried out in 1967 and in 1968 the Five Point Safety System was introduced. The seven years since its introduction have been years of significant achievement both in production and safety. Improving safety is a fundamental part of Mount Isa Mines Limited's policy and this system has been a major tool in implementing that policy. To be successful personnel need to be prepared and trained for its introduction and subsequently counselled on its use. A carefully prepared programme is required to phase in various aspects of the system and to make use of complementary steps. The system has been a success and it is anticipated that the continued drive to improve the use of principles of the system will further improve safety. It is hoped that this paper will be of value to those personnel concerned with industrial safety in Australia.

Jan 1, 1975

By R Simonato

It is now recognised that rotary sample division is by far the best laboratory tool for extracting subsamples from a lot of material. In terms of sampling theory, rotary division, by virtue of the fact that it can extract many increments from the lot during the division process, radically reduces the variance due to distributional heterogeneity in the sample being divided. There are a number of occasions in sample preparation when it is necessary to extract a subsample of a target mass. To do this with rotary dividers taking a fixed fraction of the starting mass is a tedious task. In response to this problem, a variable split sample divider has been designed and built for the mineral industry. This paper discusses the utility of the device and presents test data showing that the machine is capable of making accurate mass split while overcoming segregation in the material being divided.

Jan 1, 2008

In those days no one worried - there were plenty of other things to do. But in'these days it is different. Everyone worries- and. because there is so much worry, emotion has entered the picture. And, worse than that, capital is being made in political circles. People who were quite unaware, five years ago, that any problem existed, have now become experts on the subject, and shout to high heaven that something should be done - and yet they go on using the leaded high octane petrol they deplore so much. And even scientists, who should know better, adduce only such evidence as fits the argument in hand. And the Press is not without blame - some of its reportings is open to serious question, whatever may be the excellence of its motives. The point is made that one should know what one is talking about. And make sure that the evidence quoted is fact - and make sure too, that all the evidence is used, not only that which suita the argument.

Jan 1, 1971

By P A Ferenczi

The Proterozoic iron oxide related Au-Cu-Bi (Tenant Creek style') deposits at Tennant Creek can be classified as syntectonic polymetallic hydrothermal replacement type mineralisation. These deposits have characteristics in common with a number of other Proterozoic iron oxide (Cu-U-Au-REE) hosted deposits in regions which include Southeast Missouri, USA; the Kiruna district, Sweden; the Great Bear Magmatic Zone, Canada; the Stuart Shelf, South Australia; and the Wemecke Mountains, Canada. Similarities between these and Tennant Creek style deposits include: 1. Tectonic Setting: Formed at shallow crustal levels (

Jan 1, 1994

Study on Preparation and Gel Performance of High Purity Montmorillonite In order to research the colloidal and thixotropic performance of the inorganic gel prepared by high purity montmorillonite, this study uses the moderate grade bentonite ores from Weifang (China) as raw material. Two-stage hydrocyclone classification was applied to obtain the high purity montmorillonite with its content of 94.8 per cent. In contrast to other methods of montmorillonite purification, two-stage purification by hydroclone has the advantages of larger throughput and easily achieving auto-control in industry, and purified products with different montmorillonite content can be obtained by this method. And then the inorganic gel was prepared by the prepared high purity montmorillonite and its colloidal and thixotropic performances by measuring the flowability and thixotropy were further studies. Research results show that the inorganic gel has plastic body liquidity, the viscosity decreases with the increase of the shear rate, the static and dynamic shearing stress values are 33.98 Pa and 91.89 Pa, respectively, and the thixotropic value is 95.2 dyne+s/cm2, which indicates that it has preferable colloidal and thixotropic performance. Montmorillonite inorganic gel prepared by bentonite with high montmorillonite content and low-layer charge has better gel performance.

Sep 13, 2010

Workplace Centred Learning, (WCL), is a learning strategy which helps organisations cope with the constant change in skill requirements that is part of business today. WCL focusses on the specific needs of the workplace and provides the structure and sets the standard whereby the required competencies can be transferred between individuals. Learning is considered part of the job and ownership is achieved by involving individuals in all aspects of the learning system. Each individual in a WCL system is considered both a learner and a teacher. A significant advantage of WCL over conventional training systems is that it responds quickly to changing requirements, and once in place, becomes self-sustaining. That is, once implemented, the system provides mechanisms to detect and respond to changes in skill requirements as they arise. WCL is a competency-based system with multiple levels of validation. It provides a flexible approach to skills development that recognises both the needs of the workplace and the needs of the individual. WCL was developed in collaboration with ALCAN Aust Ltd and is currently being implemented by companies within Australia and overseas.

Jan 1, 1995

THE manufacture of Portland cement on a commercial basis dates back to the year 1824, when Joseph Aspidin, of Leeds, patented his process. It was, however, only within the past 25 years that the cement of to-day commenced its history, and during that period manufacturers have constantly tried to improve the grade of cement.The introduction of the rotary kiln at the opening of this century was the starting point of rapid development in the process of manufacture, and in the quality of the cement produced.Following on the rotary innovation came the wet process. This at first was used only where the raw materials were of a soft nature; but to-day nearly all classes of materials can be treated by this method. Oompared with the dry process, it allows for greater refinement of raw materials, more intimate mixing, better chemical combination, and economy in fuel. Taking advantage of this, the manufacturers in England and America are in a number of cases substituting the wet for the dry process.Subsidiary machinery throughout the factories, such as crushing and grinding mills, have also been vastly improved. The chemists, too, have done their share in the work. Long and careful research has proved the necessity for accurate proportioning of raw materials, thorough mixing, and very careful burning. All these factors combined have given us the product of to-day, which is consistent within very narrow limits, and far superior to that of the beginning of this cement era.

Jan 1, 1926

IN presenting the following short paper the writer hopes to illustrate some uses of explosives in industrial work under conditions different to those prevailing on mining fields. This paper is based on experience gained at the Newcastle steel works of the Broken Hill Proprietary Company Limited. The management had decided that as soon as No. 2 blast furnace which is of an improved design was ready to be put into commission, No. 1 blast furpace was to be dismantled and reconstructed to a similar design to No. 2 furnace. This reconstruction entailed the removal of the brick lining of the furnace shaft, and, also the removal and disposal of the,"salamander" and hearth-lining. For the information of members who may possibly be unacquainted with the term "salamander," it might be explained that this term is used by iron metallurgists to denote the mass of iron and slag formed at the- bottom of the furnace, whilst in commission.The method of disposal depends upon the size and nature of the salamander, and in the case under review it was decided to bury it below the hearth of the 'furnace' to be reconstructed. A passage-way was made in the concrete walls of the cast house, and the sand-filling of the cast house removed sufficiently to allow of the concrete foundations of the furnace being reached. This passage-way was extended until the hearth was encountered. The next operation was the removal of the hearth-lining below the salamander. The removal of the concrete was not difficult...

Jan 1, 1921

By J P. Moodie

Recent trends in flotation technology are briefly reviewed. These show that considerable development has been made as the operators, suppliers and technologists have responded to the challenges of the industry. Most of these advances have been based on empirical and phenomenological methods. There is a considerable opportunity to make further advances through a more fundamental, scientific approach. Some of this work is discussed and, although progress is being made on this front, industrial uptake has been somewhat slow. A number of specific issues facing the industry are discussed.

Jan 1, 2005

The Mt Lyell Mine at Queenstown, Tasmania was re-opened in 1995 by Copper Mines of Tasmania Pty Ltd, a wholly owned subsidiary of Mt Lyell Mining Co Ltd. The re-opening followed over 100 years of copper and gold mining at Mt Lyell. Major changes in practice were implemented across the site. Preventing further damage to an already disturbed environment was a major priority. Sublevel caving, at a lower cut-off grade, replaced open stoping for the deep underground mining. Development and later stoping are handled by a contractor, National Mine Management Pty Ltd, in the largest underground contract awarded at the time. Large scale sublevel caving was new to Mt Lyell and not widely practised in Australia, requiring studies and systematic development of the method, particularly in drilling and blasting. Rehabilitation and upgrading of mine infrastructure have been and will continue to be a challenge. The mine has, since 1995, returned to being a stable producer with potential for growth.

Jan 1, 1998

The reliable estimation of ore reserves in mineral sand deposits depends on drilling methods and assay techniques that have been specially developed within the industry. Improvement of these techniques is a continuing process, as variations within and between deposits are highlighted during the actual mining operation. Constant monitoring of metallurgical losses along with mineral production allows comparison of mineral tonnages accounted for by mining, with original calculated reserves. A review of ore reserves in the Jerusalem Creek field from scout drilling in the sixties, through mining in the seventies, shows the progression from understatement prior to mining, to the present when more than two thirds of the reserves have been depleted.

Jan 1, 1979

By D Fargher

BHP BillitonÆs Cannington operation began production in 1997 and is presently the largest tonnage and lowest cost single mine producer of both lead and silver in the world. The original design capacity was 1.5 Mtpa and this has progressively increased via a series of debottlenecking projects in both the mining and milling operations. In 2003, 2.39 Mt of ore was mined, whilst 2.31 Mt of ore was milled. In February 2003 Cannington received approval to expand the project to a sustainable capacity of 2.4 Mtpa. This resulted in underground development into the northern zone, upgrades to the concentrator, increased accommodation at site and power station capacity. The Cannington project development team implemented a partnership approach to the project. Fraser Osborn Engineering and Outokumpu Technology worked closely together with the Cannington team to meet all of the project constraints.

Jan 1, 2004

By Canning RG, Uusna S, Goodheart BA

The paper outlines the development of"a process for removal of iron oxides from ilmenite, thereby upgrading the TiO2 content of Western Australian ilmenites, from 55 to approximately 90 per cent. In the first stage, the iron oxides are reduced with solid carbon (coal) to metallic iron. Experimental reduc- tions were carried out in crucibles,, a fluidised bed and a small pilot plant rotary kiln. The reduced'ilmenite is,then agitated in aerated water, in the presence of catalysts, so that the iron "rusts" away from the ilmenite'grains and the precipitated iron oxide is easily separable by decantation. The influence of variables on the rates. of reduction and oxidation are discussed, The oxidation rate was exam- ined for both - the' physical oxygen-transfer characteristics and electrochemically by reference to Peurbaix diagrams, which plot redox potential against solution 'PH, The upgraded ilmenite is expected to be an attractive material. for pigment -manufacture,, and the iron oxide has prospects of being a marketable by-product. The process may possibly be. applied, to .other..ores.

Jan 1, 1964

By M Thomas, S Lambert

The Tugun Bypass Tunnel in Gold Coast, Australia was constructed using diaphragm walls with the top-down cut-and-cover method to allow simultaneous construction of an airport runway extension above the tunnel, whilst excavation of the tunnel continued underneath. The tunnel was built in an environment of high groundwater table and deep deposits of alluvial and estuarine soils with the toes of the walls founded in soil deposits. There was a potential risk for differential settlements to occur between the diaphragm wall panels, caused by the runway fill placed over the tunnel roof during excavation. Dewatering within the diaphragm walls was required to facilitate the construction of the tunnel. The tunnel was also built in an area where environmental considerations were of great importance. Three-dimensional numerical modelling was undertaken to predict the differential settlements of the tunnel with considerations of varying subsurface profile, staged excavation and dewatering, non- uniform surface loading and complex soil-structure interaction. Field instrumentation and monitoring was implemented to confirm numerical predictions.  

Jan 1, 2008