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Pyrite is a significant gangue sulphide mineral in the Ok Tedi copper ore. Its presence in the flotation concentrate is not entirely desirable since it lowers the grade of the final copper concentrate. Lime depression of the pyrite has been practiced with some success. However, it has been observed that at the pH for pyrite depression a significant amount of the pyrite particles still float. To obtain further insight into the problem this work has been conducted to determine the composition, natural floatability and xanthate flotation behaviour of the various types of pyrite in the ore. The flotation results show that while some types of pyrite float well at high pH values, others are readily depressed. The implications of these results for Ok Tedi flotation plant have been Considered.

Jan 1, 1997

In Australia a social impact assessment (SIA) is generally required prior to the approval of a mineral resource extraction or processing projects as a part of the Environmental Impact Assessment (EIA) process. In recent years there has been increased attention on the adequacy of the SIA process applied in major project assessment. Most applications have focused on the impact identification process with little attempt given to the community negotiating power over how impacts will be addressed. The impact assessment tends to occur at a single point in time, with no subsequent re-evaluation or ongoing social impact management and monitoring process. The assessments rarely specify how responsibilities for impacts on communities may be apportioned between project proponents and government, and have been inadequate in dealing with cumulative project impacts. In Queensland, concern about these shortfalls have led to the release of the Sustainable Resource Communities Policy 2008 and requirements for social impact management plans (SIMP) to be developed for each resource development in the State. In this paper a 'pressure-state-response' approach to impact assessment is used to develop an 'impact-response-monitoring-evaluation' (IRME) framework that can be applied to ongoing evaluation and monitoring of social impacts. The framework is applied to coal resource developments in the northern Bowen Basin in Queensland to identify core requirements in a SIMP. The IRME framework is flexible enough to be implemented at various spatial and time scales, for the wellbeing of the local and regional mining and non-mining communities in Australia. The framework can be further examined in other mine developments and could be integrated with the existing mining or environmental protection acts.

Jun 1, 2010

By Newell R

The influence of layering on the rate of heat transfer through a packed bed consisting of particles of two different sizes and heat capacities has been determined by measuring the heat front velocity through beds of quartzite particles and iron ore pellets. The heat front velocity through the layered beds was less than that through a bed consisting of a random mixture of the par- ticles. This is due to the formation of an interface in which the smaller pellets in one layer penetrate into the layer of quartzite Below.

Jan 1, 1987

By E A. Agorhom, P N. Aabulleh

The bulk of the worldÆs production of iron ore is processed into steel. The needs of the steel industry therefore demand a high exploration and exploitation of iron ore. One trend within the industry has been a great increase in the demand of iron ore and this is reflected in an increase in world steel production from 1955 to date. In addition to the high demand for steel, is ChinaÆs high appetite to feed its steel industry. It is therefore important that the iron ore potential of Ghana is showcased for eventual exploitation by potential investors to meet this enormous demand for the commodity in the industry globally. Ghana has three main iron deposits of potential industrial and commercial importance. They are: Shieni sedimentary iron ore (reserves: 1.270 X 106 metric tonnes), Pudo titaniferous-magnetiferous iron ore and the Opon-Mansi lateritic iron ore deposits. The Opon-Mansi iron ore deposit occurs in the Western region of Ghana. The ore deposits are located on top of the range of 15 hills, which extend over a distance of 24 km from Opon-valley, south of the Western region to Dunkwa. The area has an estimated 147 Mt of iron deposit, with Fe content of 52.5 per cent. This paper looks at the iron ore potential of Ghana and how it is capable of attracting potential investors to exploit this valuable mineral for global consumption.

Jan 1, 2007

By Sweet I. P

Stratigraphic correlations across the Mur- phy Tectonic Ridge are crucial to regional corr. elations between the Mount Isa and McArthur River areas. Recent work in the Westmoreland and surrounding areas has substantiated the earlier general correlations between the Mount Isa and McArthur River sequences. The Mount Isa and McArthur Groups, and their equivalents, remain prime prospecting targets for major lead-zinc deposits of the Mount Isa and R.Y.C. type. A prospective area for Redbank-type copper mineralization is suggested.

Jan 1, 1974

By Aylmore M. G

Samples have been taken from a two-stage industrial gold roaster treating a pyrite/pyrrhotite/arsenopyrite concentrate, in order to describe the mineralogy, composition and surface area of the calcines. Sulphides oxidised to produce a porous magnetite in the first stage and a porous hematite in the second; pyrite predominantly roasted via a pyrrhotite intermediate. Sulphur was eliminated in both the first and second stages whereas arsenic was eliminated in the first but retained in the second, partly as rims on hematite particles. The finer sized particles from the cyclones and electrostatic precipitator, while having the greatest surface area, were the most refractory with respect to gold solubilisation, probably as a result of incomplete decomposition (through short-circuiting) in the first stage, and through a combination of factors such as overheating and entrapment of sub-microscopic gold in the second stage.

Jan 1, 1992

By Abraham B. K, Jensen B, Gillies A. D S

The aim of the research was to investigate the feasibility of using an impedance cell and ratio-transformer bridge to measure solids content in coal slurry pipelines. It appeared that this technique could be developed to measure variations in conductance which correlate with solids content. Successful implementation of the measurement technique would have a variety of applications in existing coal wash plants and the potential for automatic process control. A small pilot plant was designed for a feasibility study. This was a closed loop system in which the coal was uniformly dispersed in a tank with a variable speed agitator and then circulated through an external pipe returning to the top of the tank. The impedance cell was located near the end of the external pipe. Slurry concentrations were varied from clean tap water to 50 per cent solids by weight with the addition of weighed quantities of dry coal dust. Ratio-transformer bridge measurements showed that variations in individual observations were equivalent to measurement errors of about two per cent. These probably reflect variations in concentration of the mixture in the pipe. Data for increments in concentration of one per cent indicate that this is about the limit of resolution of the current system. The paper discusses the principles of operation of the impedance cell and measurement system. Results from the pilot study and proposed improvements in the impedance cell design are examined.

Jan 1, 1995

Good morning and thank you for the opportunity to address this yearÆs New Zealand Minerals Conference.   As you have already heard from the Associate Minister of Energy, the Government believes that the minerals industry is an important part of our economy. In particular, our coal and lignite resources have the potential to play an important role in New ZealandÆs energy sector as both a primary fuel and as a means to produce electricity.   The Government has taken a keen interest in the primary fuel sector given the declining reserves of natural gas sector. The energy sector is a key driver of economic growth and it is therefore critical that we have a reliable supply of primary fuel as part of the energy mix.   In a global sense, New Zealand is like many other countries regarding the need to secure energy for the future. Natural gas will be a key bridging fuel in the transition from an energy market based on fossil fuels to one based on renewables over the next century.   However, natural gas as a solution to this energy transition has some pragmatic limitations for New Zealand. There is uncertainty as to when new domestic reserves of gas can be discovered and developed. And the alternative of imported LNG poses a number of costs and risks to the economy.   New ZealandÆs coal resources are vast-estimated to be enough to last hundreds of years at the current rate of extraction. The main question is can extraction be increased and sustained to meet the demand of domestic power producers and at the same time meet commitments to lucrative international markets?   At this point it is appropriate for me to place coal into context with Governments overarching policy objectives for energy. The Government has stated objectives for the energy sector emphasising energy efficiency and an increased focus of renewable energy, while still ensuring security of supply and certainty as to energy costs and risk. Coal certainly can make a contribution to these objectives going forward.

Jan 1, 2005

By MJ SMITH

For the past 150 years, drilling and blasting has been an integral part of the underground mining industry in Australia. Ever since Busby's Bore was developed using black powder to supply Sydney with water, miners have been drilling holes, filling them with explosives and blasting the rock into a manageable size. The drilling was fairly straight forward but the explosives were always a mysterious commodity. It worked, but how and why? The explosives industry is now working much closer to the mining industry to dispel these mysteries and also to aid the advancement of explosive technology. This paper looks at the results of these advances in the form of explosives, accessories and blasting systems.

Jan 1, 1992

By C R. Headley, S O. Hille, N P. Jacob

The redevelopment of the Telfer Gold Mine in the Pilbara region of Western Australia was primarily based on the construction of a 17 Mtpa dual train concentrator coupled with open pit and underground mining operations. The unique copper-gold orebody at Telfer requires the application of complex flotation conditions normally reserved for base metal concentrators, where two competing minerals are managed into separate products. This paper describes the commissioning of the flotation circuit, the process modes and the master/slave relationship that flotation has with a variable orebody.

Jan 1, 2007

By N Steenkamp, L Furstenberg, W Cele, M Richter

Managing productivity and improving efficiency for a healthy return on capital employed have become key mining industry strategies under prevailing tough global market conditions. However, achieving this in a multisystem environment such as a mining operation can be daunting. The field of discrete event simulation offers some relief, giving engineering teams insight into multivariable systems and stochastic processes. It allows for integrated system thinking and domain expertise to be woven into project thinking fibre. Directed system optimisation and therefore improved efficiency becomes possible. Furthermore, capital discipline accrues from optimal upgrade investments. This paper illustrates the practical application of this approach by reviewing a typical case study for a direct shipping iron ore operation. Dynamic simulation was used to establish maximum processing plant capacity under varying material characteristics and identify capital-efficient upgrades for increasing production.The study started with descriptive statistical analysis of existing data. Discrete equipment and system capacities were defined, followed by static plant mass balance calculations to establish bottlenecks and overall static capacity. Equipment ‘uptime’ and ‘downtime’ analyses established system and overall plant availability and utilisation. From this information, a dynamic simulation model could then be developed and initially calibrated against actual plant performance to verify its robustness. Once confirmed to accurately represent existing plant dynamics, system capacity response to variable changes could be tested to ultimately determine maximum plant capacity. Additionally, plant optimisation was incorporated to arrive at optimal upgrade points. Maximum capacity and necessary upgrades were established as a function primarily of feed size distribution. Additionally, the interfacing effects of rehandling feed material to the final product grade and potentially to life-of-mine were established as important outcomes. The results of the study illustrate the value of using dynamic simulation models to realistically and cost-effectively increase throughput.CITATION:Cele, W, Furstenberg, L, Richter, M and Steenkamp, N, 2015. Capacity evaluation of iron ore processing facilities utilising dynamic simulations, in Proceedings Iron Ore 2015, pp 597–604 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Luck D

Current methods of mucking out small development tunnels are a major limitation to improved efficiency and high rates of advance. This is particularly true in the deep metalliferous mines of South Africa, where the harsh environment, remoteness of operations and the hard abrasive rock conditions mitigate against the use of the tunnel borer type of equipment. The Loader Distributor Train was designed to overcome the special problems of hard rock tunnelling. It combines advanced innovative technology with proven simple methods of operation and maintenance. The system aims at taking advantage of new, efficient and cost effective power sources in South African mines based on replacing compressed air with electro hydraulics and the new concept of hydropower. It also introduces electronics and computer technology, for both automatic control and fault finding, into the production environment. The system is designed to permit sophisticated equipment to be operated and maintained by a semi skilled labour force. Although still undergoing trials it is believed that the Loader Distributor Train will prove highly effective, and that the new concepts offer considerable potential in areas other than flat tunnels, in particular the cleaning of inclined shafts.

Jan 1, 1986

By R Bertuzzi

Permanent rock bolts in civil engineering are taken as having to serve their design purpose for at least 50 years. In many projects the design life is specified as greater than 100 years. A review of recent Australian tunnelling projects shows that substantial differences exist in the level of corrosion protection provided for permanent steel shafted rock bolts. This paper reviews the current state of practice and sets out what the authors consider to be appropriate requirements for corrosion protection.

Jan 1, 1999

By A G. L Pratt, C Rossetti

The implementation of mass mining methods for large metalliferous deposits has led to the development and application of increasingly sophisticated automation and condition monitoring technologies in these mines. This technology aims to increase safety, equipment utilisation and monitoring of critical aspects of the underground ambient and geological environments. The communications networks required to support these aims and their associated technologies have evolved accordingly, and have done so in a demanding underground environment. The evolution of communication infrastructure for large underground mines has developed from basic analogue telephony to high-bandwidth optic fibre based systems. The latter is now the media of choice. More recently the developments in wireless broadband equipment designed specifically for underground environments have emerged to satisfy the needs of automation for mobile equipment and shaft conveyance communications. The use of internet protocols for industrial control and monitoring has led to the application of ethernet-based backbone networks as a standardised approach. There may also be a need for the integration of range of communications platforms in a mining operation to realise the full advantages offered by automation and condition monitoring technologies. As a result the design of the communications backbone networks for underground mines has started to become the domain of information technology professionals. Without these networks, the analysis of equipment utilisation is often not possible. The improvements that can be brought about by æsweating the assetsÆ and the transmission of business critical information are the most significant benefits of an integrated communications system. These benefits far outweigh the costs of strategic planning, subsequent specification and implementation of communication networks themselves. Future developments in mining systems and communications technology will continue to drive the demands placed upon communications networks as an essential mass mining infrastructure item. This paper outlines the benefits of secure high bandwidth backbone communications networks for mass mining operations and the need for a high degree of strategic thought and demand forecasting in the planning stages for these operations.

Jan 1, 2008

By A Bennett, A Peck

BHP has recently constructed a Hot Briquetted Iron Plant at Port Hedland in the Pilbara region of Western Australia. Supply of iron ore fines to the plant is by conveyor from the companyÆs existing Nelson Point stockyards. The conveyor passes under Port Hedland harbour in a concrete segmentally lined tunnel, approximately 1030 m long and with a 5.1 m external diameter. The tunnel was constructed by a Tunnel Boring Machine (TBM) which both excavated the ground and erected the tunnel lining. The tunnel was bored between cut and cover in situ concrete portal structures, the TBM being launched from the Finucane Island side towards Port Hedland town. The alignment required lengthy gradients of 1:6 on either side of the harbourÆs dredged channel, under which the tunnel is bored with a minimum clearance of 8 m.The tunnel is fitted-out with:1800 mm belt conveyor capable of 10 000 tph;walkway along which a specially designed inspection/ maintenance vehicle can run; andtunnel services including power, light, fire detection and suppression communications, water mains for wash down and sumps and pumps for drainage.This paper gives a general overview of the design and construct contract, important aspects of the design and the construction process itself.

Jan 1, 1999

By D Morris

This presentation discusses a water filtration technology termed Fabric Media that is somewhat novel to the Australian market place and reports several recent mining industry installations. Like many novel household cleaning products, the Fabric Media technology applies the science of active washable micro fibres as the means of capturing contaminant solid particles. The simple Fabric Media water filtration product offers several attractive attributes when compared to the more traditional media bed filtration processes such as sand filters, and barrier filters such as micro membranes. A micro fibre based filtration media enables both superior adsorption for the contaminant and wash ability. Stronger adsorption capture enables a much higher flux and greater solids loading density for the filtration task, meaning that lower cost and smaller footprint equipment is available. For Fabric Media water filters, a textile weave is selected that minimises the flow backpressure for a given particle size separation. Thus for an equivalent filtration performance this provides a much lower operating energy requirement, generally between 50 and 80 per cent less than for a sand filter. A Fabric Media is not abrasive to itself or to the filter tank. The filtration performance remains constant and predictable. The equipment life is much longer and the asset value of the new filtration equipment should maintain throughout the project life. Fibres are extremely mechanically robust and chemically inert. Fabric Media survives repetitive exposure to a rapid mechanical washing event providing high wash efficiency with minimum equipment off-line time for the backwash. Dislodging captured contaminants by a high-speed mechanical agitation enables a minimum off-line time during backwash events. The vigorous backwash destroys adhering flocculant and eliminates the formation of mud balls, which can permanently foul sand filters. The mechanical agitation wash of the Fabric Media water filter ensures complete removal of grease and biofilm, which can adhere and block a membrane surface. In comparison to sand filters and micro filtration membranes, the Fabric Media product is applicable to a significantly wider range of solids concentrations without permanent damage. The technology is very forgiving to excursion in plant control and is therefore considered a very operator-friendly concept.

Jan 1, 2006

By Jensen B

The investigation of the explosion characteristics of nine Bowen Basin (Central Queensland) dust samples in a suitable coal dust explosion chamber using a new dust concentration probe provides several advances in the area of coal dust explosibility testing. The 20 litre explosion chamber, of novel design, uses rotation of the main body of the chamber together with air jets for dust dispersion, and allows testing of different types of explosion initiators and analysis of the explosion characteristics of coal dust/methane mixtures of varying concentrations.A new development was a dielectric dust probe for the measurement of coal dust concentration. A capacitive micrometry technique was successfully adapted to measure dust concentration. The system uses a ratio-transformer bridge for measurement of small changes in a capacitive probe designed to sample a representative volume. The device is accurate, and is capable of operating in the hostile environment within the explosion chamber.The explosion chamber and dust probe characterise the explosive potential of coal dust samples by determination of the dust lean limit concentration in varying mixture with methane. Plots of lean limit points obtained in this way present an explosion curve for each sample which indicates the potential of the coal dust/methane to explode under the conditions of initiation in the chamber. The explosion curve obtained for each sample presents a unique signature that appears to reflect the physical and chemical characteristics of the dust.The results from this series of laboratory experiments appear to provide a useful index and indicate potential areas of interest for future research.

Jan 1, 1991

By Dip L. B

This paper describes the new legislative regime that will apply to the regulation of the minerals industry in New Zealand.The reform of New Zealand's minerals legislation was initiated in January 1988 when the Minister for the Environment, Rt Hon Geoffrey Palmer, announced the Government's intention to review all the major laws governing New Zealand's resources. The Resource Management Bill is scheduled for introduction to the House in December 1989 and its date of enactment is scheduled for June 1990.

Jan 1, 1990

By N Madani, N Battalgazy

Geostatistical simulation has been widely used in mineral resource classification of metalliferous deposits based on international standards such as JORC code which is one of the most extensively used around the world for reporting the mineral resources and ore reserves alongside with objectives of the companies (Sadeghi, Madani and Carranza, 2015). However, the modeling process becomes challenging whenever the relationship between the variables of interest is complicated and cumbersome to model. This characteristic sometimes manifests itself in complex spatial and global cross-correlation measures, deeply depending on the formation and genesis of the deposit. The objective then is to generate the models that not only reproduces these significant characteristics, but also, it leads to a better understanding of a mineral resource estimation and successive decision-makings. In this respect, there are different approaches taking into account the spatial correlation structures, for which can be classified as independent simulation, co-simulation, and factor-based methodologies. In this paper, three techniques: Turning Bands Independent Simulation (TBSIM), Turning Bands Co-Simulation (TBCOSIM) and Projection Pursuit Multivariate Transform (PPMT); from those aforementioned approaches are selected to model two cross-correlated variables (Iron and Aluminum Oxide) belonging to an Iron ore deposit located in Brazil, in order to examine which methodology better reproduces the corresponding complexity in terms of local correlation measure. CITATION: Battalgazy, N and Madani, N, 2018. Mineral resource assessment in complex ore deposits based on international standards, in Proceedings Complex Orebodies Conference 2018, pp 79–81 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

An algorithm is described which leads directly to a unique set of coal washing parameters which, in two or more parallel streams, will give maximum yield of product at a given ash. This occurs when all parallel streams are washed to the same incremental ash. This strategy is shown to offer a considerable increase in yield compared to the simpler strategy of washing each stream to the same sumulative ash.

Jan 1, 1987