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By R A. Medower

This paper provides a glimpse into the future of minerals processing with emphasis on æAutomation InnovationsÆ for the new millennium, particularly those involving advanced process control and innovative new applications of process control technology in 2007.

Jan 1, 2000

By McKee DJ

Future mineral processing developments will be of two types. There will be a continuation of the advances of the last 20 years including major increases in equipment capacities, the development of reliable on-line instrumenta- tion, the use of digital computers for automatic control, and the greatly expanded use of in-situ leaching techniques. However, there will also be a need for innovations as the industry faces a different set of problems to those involved in cost and extraction efficiency considerations. These new problems include those relating to energy usage, environmental pressures, and the further development of large low grade deposits and small, high grade metallurgic- ally complex deposits. Present technology does not appear adequate to solve many of these new demands. New treat- ment concepts will be required, and the immediate outlook in this regard is not encouraging. A major research and development task in mineral processing over the next 20 years will be to seek out new ideas and develop them, and this must be pursued with imagination and determination. Both the continuation of the present research pro- grammes and the development of new methods will require a steady supply of highly qualified technical personnel. These people are not being produced in the numbers required, and this situation must be urgently rectified.

Jan 1, 1981

With the use of 86 rock drills of the jackhammer type at the West Lyell Open Cuts of the Mt. Lyell Mining & Hailway Co., it is of importance to determine the economic as well as the physical life of these machines. With this purpose in mind records have been kept of the footage bored and the cost of new parts placed in each machine, and the following procedure adopted.A graph is plotted for each machine showing the footage bored as a horizontal line and at each 5,000 feet of boring the total cost of new parts noted on this line. (See l"ig. 1.) Thus at a glance it is possible to see... the amount of work done by each machine and the money spent on it in new parts. However, it is difficult to visualise from this graph the increase in the cost of new parts for each machine as its life advances. To obviate this difficulty a curve is plotted with the cost of new parts as the vertical component and the distance bored as the horizontal component. As before the cost of new parts are taken at each 5,000 feet bored. (See Fig. 2.) The curves so obtained are particularly interesting for two reasons:1. Each machine has its characteristic curve.2. The curve always steepens.Some machines are found to have relatively flat curves, others flat curves for approximately 15,000 feet of boring, and others steep gradients from the begining.This demonstrates that it is not always economic to discard a drill after it has been in service for a certain length of time or after it has bored a specified number of feet. Each drill has its own characteristics and so must not be regarded as one of a class, but considered on its own performance.The following use of these curve diagrams has been made to determine whether a machine has reached the end of its economic life. Figure 3 shows...

Jan 1, 1942

By Storey AG

Following initial plant scale work on the development and performance of 'spray' oil lances, a full scale room temperature model of the blowpipe-tuyere region of a blast furnace was built to study the basic aerodynamic features of auxiliary fuel injection procedures. Mobilwax 2305 was used as a substitute for Bunker C oil fuel in view of its similar physical properties and the fact that the atomised droplets could be frozen in flight and size, distribution analyses made for various operating procedures. It was shown that secondary atomisation processes far outweighed the importance of any primary atomisation procedures in determining mean Sauter Diameters particularly at high windrates typical of current blast furnace technology. It was also found that good spray dispersions across the blow pipe could only be obtaind for liquid fuels and that the lateral rate of spray dispersion was substantially enhanced by primary atomisation procedures. Mean particle diameters of sprays were found to be predictable on the basis of elementary stability theory and fell within the size range necessary for good combustion at all liquid fuel rates studied. The possible effects of high oil injection rates on flooding phenomena in the furnace bosh were considered. Comparisons show that high oil rates can lead to significant increases in the hanging factor (e.g. 'V 10% at 135 kg oil/thm) owing to increased gas flow rates/thm resulting from the presence of hydrogen.

Jan 1, 1975

My topic for today is the Crown Minerals of the future. New work initiatives are underway and the organisational structure is being overhauled. These are not insignificant changes and in this paper briefly summarises these proposals. These new work initiatives and changes to the organisational structure will have implications for the industry as a whole and also for the way individual clients interact with Crown Minerals.

Jan 1, 2003

At 9.45 pm on Thursday, 12 July 1962 glass began to flow in an endless stream from a massive melting tank in a new Whangarei factory and a vital new industry was born û right on schedule. It wasn't good glass. It was ridged. It cracked. It rippled. It obstinately refused to emerge upstairs in the cutting room in one solid continuous sheet. But all through the night, drawing speeds were adjusted, temperatures changed. And on Friday morning, at 8:30, it finally came through as sheet û not perfect as yet, but sheet glass all the same. The rest is only a matter of time. Unfortunately, the buoyant enthusiasm displayed by the founders of the sheet glass industry in New Zealand, and the technical expertise of their European consultants, failed to bring the glass quality up to commercially acceptable standards and within six months, the company was in receivership. Taking over the role of producing New Zealand's sheet glass requirements, New Zealand Window Glass Company was formed as a partnership between two companies with long experience in sheet glass manufacture û Pilkington Brothers (NZ) Limited and Australian Consolidated Industries Limited. This paper sets out to identify the raw material requirements and controls necessary for the successful manufacture of sheet glass, and the availability and supply of suitable materials for use at Whangarei.

Jan 1, 1978

By Montagnon P, Dagois G

The use of activated carbon for gold recovery has been known for years, but came industrially on stream since the years seventies.Despite several years of experience, the criteria for selecting a carbon have not been clearly determined so far.This paper will try to highlight the user through his experience, on the most important factors which should affect his decision.We will develop:- Physical characteristics - Adsorption characteristicsand try to show that slight variations on these characteristics may have important consequences on the plant design and profitability.

Jan 1, 1984

By J Aitchison, G Clarke

A reappraisal of the stratigraphy, new regional kinematic analysis and thermobarometric data allow a new interpretation of the metamorphic zoning and tectonic structure of the Upper Eocene high-pressure metamorphic core complex of northernNew Caledonia allow a three steps evolution to be proposed: 1. subduction and understacking of previously thinned continental crust elements; 2. subduction blocking due to the crustal thickening; and 3. crustal thinning and extensional detachment during the diapir-like uplift and unroofing of the eclogitic core. Steps 2 and 3 may be partly contemporaneous. Such a model accounts for the thermobarometric and radiochronologic data, and also for the weakness of substratum deformation during the emplacement of the ophiolitic nappe

Jan 1, 1995

By M J. Cole, J Zhou, D J. Borrow, S M. Iveson, K P. Galvin, J L. Sutherland

New technologies can easily take around ten years to commercialise. Strong research support is needed in parallel with the process of innovation and commercialisation, in building a deeper understanding of the underpinning physicochemical and hydrodynamic forces that deliver the separations, in achieving improvements, in the deployment of a new technology, and in expanding the innovation platform to create new IP. External investment beyond the research, derived from the genuine value proposition of transformational change, funds the pathway for traversing the so-called Valley of Death.

Aug 24, 2022

By Ritchie I

Copper minerals are often associated with gold ores. These create processing problems since cyanide solutions are not selective for gold alone. Copper minerals are also leached by cyanide, and typically each one per cent of `reactive' copper in the ore consumes about 30 kg t 1 cyanide. Once in solution, copper cyanide species create further processing problems as they adsorb onto carbon along with the dicyanoaurate ion. These problems make conventional cyanidation of gold ore uneconomic if the ore contains too much copper. As a result, methods of economically processing gold-copper ores are becoming of increasing importance.One of the more promising methods of treating these ores is by selective leaching of the gold by an ammoniacal cyanide solution, a method first described by Hunt in 1901. This method is already in commercial use in Mauritania, treating copper/gold tailings. In general terms, the addition of I - 2 g U1 ammonia to a standard cyanide leach solution causes a significant increase in gold extraction and decrease in copper extraction. However, early testwork on this system has concluded that the optimal leach conditions are critically dependent on ore composition, and the mechanism is not well understood, making predictions of best conditions impossible.

Jan 1, 1997

By M D. Basuki Dwi Priyono

The Toguraci low sulfidation epithermal gold vein deposits are located 2 km WSW from the Gosowong mine and form part of the Gosowong Goldfield. The goldfield lies within a Neogene magmatic arc on Halmahera Island, North Maluku Province, East Indonesia. The terrain is moderate to steep, rainforested, and poorly outcropping. Exploration and mining operations are being carried out within the PT Nusa Halmahera Minerals Contract of Work (exploration tenement) jointly owned by Newcrest Mining Ltd (82.5 per cent, operator) and PT Aneka Tambang Tbk. (17.5 per cent). First pass exploration of the Gosowong area began late 1992 resulting in the discovery of weakly developed porphyry copper mineralisation (named Bora) at Toguraci in 1993. Early in the evaluation of this porphyry an overprinting epithermal Au/Ag mineralisation event was recognised, however exploration focus remained on the Bora porphyry deposit for some time. The discovery of the nearby Gosowong epithermal gold deposit and the exploration of other prospects in the area further diverted attention and funds from Toguraci. It was not until year 2000 that Toguraci was seriously reevaluated as part of a detailed appraisal of the epithermal gold potential within a 5 km radius of the Gosowong gold mine. A fly-camp based drilling campaign using man-portable rigs was undertaken between August 2000 and March 2002. All exploration at Toguraci was then stopped pending government approvals to mine. These were finally issued in May 2003 and immediately drilling restarted and pre-mine approvals (eg the environmental impact study) were sought and granted. The first Toguraci gold bar was poured in February 2004. Exploration at Toguraci and elsewhere in the Gosowong Goldfield continues today.

Jan 1, 2004

By G W. Wilson, P Ritchie, N A. Currey

The design and rehabilitation of potentially acid forming (PAF) waste rock dumps is site specific, being a function, among other factors, of the rock types, the dumping and storage method employed, and the climatic setting. The æstore and releaseÆ cover system developed to manage acid rock drainage (ARD) from mineralised waste rock dumps at Kidston Gold MinesÆ open pit operations in the semi-arid climate of North Queensland, Australia, has been monitored for seven years. The paper describes the philosophy behind the design of the PAF dump and æstore and releaseÆ cover system and the adaptation of the cover system over time to suit KidstonÆs conditions. The results of monitoring over the seven years since the first cover was constructed are presented, and the approach being taken at Kidston to ensure that the risk of impacts from any residual ARD is accommodated and to facilitate lease surrender are described. The Kidston story is a valuable case study of a successful approach to remediating an identified source of ARD in a semi-arid climate, which has actively engaged all Stakeholders.

Jan 1, 2003

By R Bose, M Bovell, G Cheong

Grinding media is a major consumable in mineral processing and therefore decreasing costs associated with its consumption is regularly considered a key goal for the minerals processing industry. Grinding media manufacturers have historically developed steels with improved wear life for their products as a way of delivering incremental media quality improvement. This has included increasing carbon levels from low-to-medium carbon steels up to the eutectoid carbon composition of 0.77% where the relationship between higher carbon and better wear performance is well understood. Producers today will regularly use grades in excess of 0.8% to further improve wear performance particularly for rolled grinding media.This paper first introduces the demonstrated relationship between this increased carbon content and improved wear resistance along with metallurgical rationale behind the high carbon production process and limitations. To test the performance improvement associated with the higher carbon steel grade, a series of Marked Ball Wear Tests (MBWT) were carried out. This paper also explores the relationship between ball properties, test methodology and wear performance and concludes by correlating increased carbon grade with a reduced consumption rate of between 3.1% and 6.1% in the tests conducted.CITATION:Bovell, M, Bose, R and Cheong, G, 2018. Improved forged grinding media performance with carbon content greater than 1.0%, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 559–570 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

Successful management is ultimately measured by return on shareholders' funds. This is the inescapable and inexorable discipline that ultimately rules every investment. Shareholders today are predominantly, and increasingly, the superannuation funds and insurance funds of almost all of us. We have already reached the situation in Australian investment history in which the best interests of employees can be very directly identified with the best interests of the owners of the capital invested.

Jan 1, 1992

Natural Gas has been available in New Zealand for twenty years. During that time the gas share of the energy market has grown and now natural gas forms a significant part of New Zealand's energy scene, helping consumers to achieve a higher standard of living, and reducing dependence upon imported oil.Natural gas is now used for petrochemical manufacture and power generation in addition to direct supply to consumers.As concern for the environment continues to build, natural gas will have an increasingly important role to fill in these markets. This paper sets out the background to the development of natural gas in New Zealand and identifies the current markets. It then looks at those matters which are likely to influence the role of natural gas in the 1990s.

Jan 1, 1990

The resources industry is unique in that the finite nature of resource deposits requires a participant to be constantly locating and developing new ones to replace those that are depleted. An effective growth strategy that enables new project developments to be brought on line in time and within budget is therefore of fundamental importance to any mineral resources company. This paper seeks to identify the role of the development project in the company's overall growth strategy and the key performance criteria that a development project must achieve in order to allow a company to meet its growth objectives.

Jan 1, 1997

By J Finlay, P Betts, D Milton, H Williams

The aim of this paper is to present an innovative method to help delineate potential target volumes for haematite-goethite mineralisation as opposed to more magnetic ores. This is achieved through interpretation and modelling (2.5D and 3D inversions) of ground magnetics and gravity surveys over the Koolanooka South prospect in Western Australia. The targets are assumed to be dense and weakly magnetic and hosted within banded iron formation (BIF) horizons. Geophysical interpretation (2D map) was performed using a variety of processed magnetic and gravity images (Betts et al, 2007) to determine the distribution of lithologies, to understand the structural architecture and to map out any anomalous areas of excess density (possibly indicating goethite alteration). The created geological map is used to build geological cross-sections (geometrically consistent) that were modelled (in 2.5 D) against both potential field datasets. The crosssections are consequently used as the framework to build a 3D geological model. The model defines 3D volumes of rocks including several BIF horizons. The distribution of densities and magnetic susceptibilities of the BIFs is inverted within the GOCAD«-VPmg environment to reduce the misfit between the response of the model and the observed gravity and magnetics. By combining the results of both petrophysical property distribution it is possible to map out (using classical GIS type queries in 3D) volumes of higher density and lower magnetic susceptibility.

Jan 1, 2009

By V P. Beskrovnaya

Tests for the development of a metals recovery technology from samples of a Russian gold-bismuth deposit were carried out. Gold, silver and bismuth assay reported 5.6 g/t, 3.0 g/t and 0.08 per cent, respectively. Two flow sheet options were pilot plant tested: gravity/cyanidation of gravity tailings with subsequent flotation of cyanidation/carbon-in-pulp (CIP) tailings, and gravity/flotation concentration with cyanidation/CIP of concentrates. Option 1 results showed lower gold, silver and bismuth recoveries (81.3 per cent Au, 55 per cent Ag and 74.0 per cent Bi) due to low flotation efficiency for cyanidation tailings. Therefore, a flow sheet involving gravity/flotation concentration to produce bismuth-gold concentrates (0.8 per cent Bi) with subsequent cyanidation/CIP was recommended. Gold, silver and bismuth recoveries obtained by this method to the combined gravity/flotation concentrate were 90.2 per cent Au, 83.3 per cent Ag and 80.2 per cent Bi of the ore, respectively. Overall gold, silver and bismuth recoveries were 83.0 per cent Au, 40.5 per cent Ag and 80.2 per cent Bi, respectively. Gold and silver recoveries to the cathode precipitate were 92 per cent Au and 48.6 per cent Ag (per operation). Reagents consumed for flotation were 0.1 kg lead acetate/t ore, 0.4 kg butyl xanthate/t ore, 0.2 kg T-80 frother/t ore, 0.02 kg sodium hexametaphosphate/t ore, 0.15 kg copper sulfate/t ore. Reagents consumption for cyanidation was 0.42 - 0.48 kg NaCN/t ore and 0.2 kg CaO/t ore. It was recommended to deliver bismuth concentrates after hydrometallurgical treatment to a smelter. Overall bismuth recovery including bismuth recovery achieved by pyrometallurgy was 60.0 per cent. However, it was obvious that delivery of bismuth concentrates to a smelter and their commercial treatment would be very expensive due to relatively high mass pull of bismuth concentrates (7.6 per cent of the ore weight). For this reason, thiourea leaching and hydrochloric acid leaching with subsequent cyanidation/CIP were investigated as alternatives to cyanide leaching. These two alternatives were proposed to enable optimal recovery of valuable metals from concentrates on-site. Recoveries obtained by thiourea leaching were 91.2 per cent Au, 90.5 - 91.9 per cent Bi and 77.0 - 78.1 per cent Ag. However, that method required considerable capital and operating costs. As an alternative, hydrochloric acid leaching with subsequent cyanidation was investigated. Test results showed improved gold, bismuth and silver recoveries, which were 94 - 95.9 Au per cent, 94 - 96 Bi per cent and 76 - 78 Ag per cent, respectively. Hydrochloric acid consumption was 100 kg/t concentrate or 7.6 kg/t ore. Current efficiency during electrowinning was about eight to 12 per cent. A recommended flow sheet involving hydrochloric acid leaching of concentrates, electrowinning of bismuth from solutions, recycling solutions after electrowinning and cyanidation of hydrochloric acid leaching cakes is described. Overall recoveries achieved by the proposed flow sheet were as follows: 84.8 - 86.5 Au per cent, 75.8 - 76.9 Bi per cent and 63.2 - 64.9 Ag per cent. Based on results from these tests, initial data for a bankable feasibility study and plant designing were developed.

Jan 1, 2007

By Segnit ER, Jensen G

The decoppering of soft and hard leads was investigated by stirring in an open pot, using sulfur or sulfur plus pyrites, or sulfur plus pyrrhotite, as reagents. Lead samples taken during the process were analysed for copper. Dross samples were examined by optical micro- scope, SEM and XRD. Soft lead containing silver can be decoppered satisfactorily by stirring with 0.1% S at low temperatures - close to 330¦C. Soft lead, whether containing silver or not, can be decoppered satisfactorily at higher temperatures by stirring with 0.1% S plus 0.4% pyrites. Then CuFeS2, Cu5FeS4 and PbS are formed, instead of Cu2S, CuS and PbS when using S alone. Hard lead containing tin can be decoppered satisfactorily by stirring with 0.1% S at temperatures from 320-400¦C. When stirring with 0.1% S plus 0.4% pyrites, reversion of copper from dross to lead on prolonged stirring does not occur. Hard lead without tin can be decoppered with S plus pyrites better than with S alone, but the presence of antimony hinders the decoppering, which is less effective on lead with 5.5% Sb than with 2.3% Sb.

Jan 1, 1980

By Bartrop S. B

Mount Isa mine has a long history of successful exploration since discovery 70 years ago. Remaining reserves, although substantial, exist in a scheduling framework which involves long-term production from new ore sources with attendant technical risk and major capital investment. Current exploration aims to incrementally increase reserve tonnage to maintain existing production levels as well as to provide a buffer for potential start-up delays from new ore sources. Exploration also aims to increase the net present value of the operation by discovering new major orebodies around the Mount Isa and Hilton mines.

Jan 1, 1993