Search Documents

By Liu H, Chen S

Natroalunite is one of colouring minerals in kaolin. In this investigation, natroalunite, on which Ca(II) was adsorbed, was flocculated by HPAM and kaolin was depressed in suspension. The adsorption of Ca(II) on the natroalunite surface was studied by zeta-potential measurement and Auger Electron Spectroscopy analysis. Ca(II) was adsorbed more on the natroalunite surface than on the kaolin surface. The mechanism of Ca(II) adsorption was considered to be chemical adsorption on natroalunite and to be physical adsorption on kaolin. It has been found that Na6P6O18 and Na2Si04 can strongly affect Ca(II) adsorption on the surface of kaolin, but weakly on the surface of natroalunite. The effects of degree of hydrolysis and the molecular weight of HPAM, the effect of pH and the effect of Ca(II) have been studied. The kaolin ore, containing SO3 1.05 per cent has been processed with this method. The products only containing S03 0.36 per cent and the weight ratio of concentrate 52.27 per cent were Obtained.

Jan 1, 1993

The paper presents the results of laboratory blasting and grinding experiments on a low-grade iron ore, investigating how blasting will influence the subsequent crushing and grinding operations. Increased blasting energy will lead to a reducti

Jan 1, 1998

By J White

The Eyre Peninsula (EP) has been known for its iron ore for more than a century. Edward John Eyre noted the ironstone outcrop at what is now Iron Knob in the 19th century. Sir Douglas Mawson visited and reported on the geology of the lower EP in 1906, noting the widespread presence of iron stone and the likelihood of copper being associated with the iron stone. Despite this knowledge there has been only one successful iron ore mining region developed on the EP and that is Iron Knob and the Middleback Ranges which have been mined continuously since 1899. The Middleback Ranges can justly lay claim to be birth place of the Australian iron ore and steel industries.The discovery of large scale haematite resources in Western Australia meant that there was no need to seek out iron ore that needed benefi ciation. The low price of iron ore precluded further development of the EP and many other areas in Australia and overseas. This situation changed rapidly in the mid-2000s with the emergence of China as the world’s industrial power house and the soaring demand and price for many resources including iron ore. This triggered a flurry of activity across Australia and led to the rapid exploration and drives to develop the EP iron ore. A brief examination of the magnetic maps of the EP shows the wide spread presence of magnetite and associated smaller haematite deposits. A closer look reveals the magnetite deposits to vary in formation style and host rock lithology as well as being significantly altered by regional metamorphism. *This is an abstract only. No paper was provided for this abstract.*

Jul 11, 2011

By C Smith, J Cilliers, K Hadler

Unstable flotation froths, that burst before they overflow, produce no concentrate. Increasing the froth stability to improve recovery is therefore an obvious control strategy. Froth stability can be measured readily as the fraction of air entering the flotation cell that overflows as froth, rather than bursting on the surface; the ‘air recovery.’ Air rate is one of the most significant variables affecting froth stability. It is interesting that froth stability (air recovery) is maximised at a specific air rate, above or below which it decreases. It is important for metallurgists to realise that this maximum froth stability also produces the maximum mineral recovery, without compromising concentrate grade. Flotation cells must be operated at the air rate that produces the highest air recovery. The peak air recovery (PAR) to maximum mineral recovery relationship was first demonstrated by Hadler and Cilliers in 2009. Since then, the relationship between PAR and flotation performance has been widely explored; varying air rate, froth depth and particle size. Industrially, reducing the flotation bank air rate to achieve PAR yielded better mineral recoveries than other down-the-bank air rate profiles. In this paper, we present an overview of these key developments and findings in flotation optimisation based on PAR. Furthermore, using new industrial data, we show that PAR is not just applicable to rougher-scavenger cells, but also to flotation columns. Finally, we consider the future application of such an optimising control concept. CITATION:Smith, C, Hadler, K and Cilliers, J, 2018. Flotation control using froth stability: past, present and future, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 441–454 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

The mining industry has expanded significantly in the Pacific Region over the past two decades through a mix of new developments and brownfields expansions of existing operations. Despite this overall success there are also a number of well publicised examples of less than successful minerals ventures. These problem developments highlight the fact that success cannot be taken for granted and that rigorous planning and attention to detail is essential. The dominant growth has come through expansion of existing businesses, notably alumina, iron ore and coal, achieved through both efficiency gains on existing plant and step change capacity additions such as new mines and/or expanded processing plant. This expansion has largely been linked to increased market opportunities. The major issues are the quality and extent of the host resource, achieving the market targets, and the efficiency of the expansion effort. There can be also a range of site specific issues which need to be addressed. The development of new greenfields operations is often more complex as it can bring a wide range of new issues. Depending on the nature of the development, and the companies involved, these can extend from initial financing through to obtaining a market position. Incorporating major new technology and/or establishing infrastructure and attracting staff to remote locations can also add significant challenges. This paper outlines many of the critical factors which need to be considered prior to proceeding with major expansions or greenfields developments. These will be linked to a number of developments in the region over the past decade.

Jan 1, 2004

By B G. Blacka, O Salisbury, K W. Mills, R G. Jeffrey

Whitehaven Coal Limited operates an underground longwall mine near Narrabri, New South Wales. The mining horizon in the Hoskissons Seam is overlain by a 16–20 m thick unit known as the Digby Conglomerate, a unit that is sufficiently massive to have potential to cause a windblast during first caving at the start of each longwall panel and periodic weighting throughout the panel. A program of hydraulic fracturing has been successfully used to precondition the conglomerate strata to increase its caveability at the start of each panel. This paper presents a system of temperature monitoring that was used successfully to measure hydraulic fractures at Whitehaven confirming their rate of growth, orientation and interaction with previously placed hydraulic fractures.CITATION:Mills, K W, Blacka, B G, Jeffrey, R G and Salisbury, O, 2014. Temperature monitoring of hydraulic fractures used for preconditioning massive conglomerate strata to reduce windblast, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 189–194 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By L Chaffey, M Buckland

The minerals industry has enormous potential to positively contribute to sustainable development and many leading companies have concluded that their long-term success is directly linked to their ability to leave a lasting positive legacy. While there are many examples of success, there have been failures as well and much work has been done in recent years to define the role of the minerals industry in sustainable development and identify the key elements for success. In the past, our sector could point to the taxes and royalties it paid, the exports it generated and employment it created and felt confident that its contribution would be recognised and duly acknowledged. This is no longer the case. Critics of the industry have highlighted resource-rich countries that have failed to capitalise on their resource wealth and have arguably lower standards of living than their resource-poor peers û the æresource curseÆ hypothesis. Recent research has done much to clarify the factors that contribute to a countryÆs success or failure and all stakeholders in the industry now need to include these learnings in their approaches going forward. We know that our long-term success relies on embedding a company- wide approach to sustainable development into all aspects of our business operations. In this paper we highlight BHP BillitonÆs experience in the development and implementation of policies and systems designed to enhance our contribution to sustainable development. We detail the business drivers for excellence in this area and the key external codes and initiatives that have shaped our approach. The values-based BHP Billiton Charter, Sustainable Development Policy and associated Health, Safety, Environment and Community (HSEC) Management Standards are central to our approach. Implementation is reviewed through our HSEC audit program. One area in which we have placed particular emphasis is our approach to community development. BHP Billiton has a corporate target to contribute one per cent of its pre-tax profit on a three year rolling average to voluntary community programs. As our profit stream has increased with the minerals boom this is approaching an A$100 million commitment. In our paper we detail how we are working to ensure we maximise the value of this contribution for our communities and our shareholders.

Jan 1, 2006

By C K. McKenzie, P Popov, B E. Papillon, I Kharitonenko

Flyrock produced by blasts in surface mining and quarrying is a major hazard that can result in serious injuries or property damage. This paper presents a fully integrated and automated approach for reviewing blast outcomes from a wide variety of rock blasting environments from the perspective of flyrock safety associated with blasthole collar ejections. The process is applied at a corporate level for an explosives service provider handling up to 100 blasts per day from mines, quarries and construction sites throughout the US.Flyrock risk minimisation has inspired research and the associated development of a reliable flyrock model to estimate flyrock ejection velocities and the resulting maximum projection distances of fragments. In spite of significant achievements in this area, flyrock incidents continue to occur, mostly due to implementation mistakes. An efficient preventive measure is continuous blasting process improvement that relies on on-site video recording, storage, automatic analysis and classification of the recorded blasts followed by the automatic generation of reports.In this paper, a novel blasting video analysis system that is capable of processing a large quantity of video records is presented. Blast analysis and parameter measurement are fully automated and are carried out using videos recorded with a conventional consumer camera. The blast video recording process does not require the use of surface markers, range poles or objects of a predefined size for scaling purposes.Although automatic video analysis is commonly used in many application areas, such as video surveillance, traffic monitoring and robotics, the algorithms that have been developed to recognise and track solid objects with well-defined shapes, textures and colours are not efficient at dealing with blasts, which, by their nature, have dynamically changing parameters. Moreover, very strong camera vibration caused by blasts that cannot be totally compensated by camera image stabilisers may cause conventional computer vision algorithms to fail.This paper presents novel computer vision methods developed for automatic tracking of the trajectory from a blast ejection point to the highest point reached by blast particles and the ejection velocity. The system also uses colour and motion analysis to detect the emission of toxic fumes during a blast. The solution is vibration tolerant and can differentiate foreground and background data, even in the presence of camera vibration. Moreover, the blasting video analysis method can automatically categorise correctness of the measurements and therefore indicate cases when additional visual inspections may be required to verify reports generated automatically.CITATION:Kharitonenko, I, McKenzie, C K, Papillon, B E and Popov, P, 2015. An automated system for flyrock and fume monitoring of blasts, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 417–424 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By A Campbell

Open pit blasting at Ernest Henry Mining has the potential to cause damage to nearby underground workings. This paper is a case study of the blast vibration management project that was conducted to ensure open pit blasting did not adversely affect the stability of upper production levels or cause damage to the underground primary fan units. The two upper levels of the underground mine surround the lower portion of the open pit mine. The remaining underground mine workings are directly below the open pit mine. This paper details the process developed to prevent open pit blasting causing excess vibration in the underground mine. Measurement of test blasts combined with historic blast monitoring data was used to determine site specific blast vibration parameters. Threshold vibration levels for blast-induced damage to underground drives and the fan chambers were developed from benchmarking and non-linear numerical modelling. A Monte Carlo simulation model was used to predict vibration levels in critical underground areas. Blasts predicted to exceed maximum vibration levels could then be redesigned to avoid damage.A scale distance law for determining peak particle velocity (PPV) from the distance and charge weight of blasts was developed. Underground observations were used to develop a site-specific relationship between PPV and ground support/rock mass damage. A Monte Carlo superposition prediction model was developed and compared to measured data to refine input parameters. Standards for redesigning open pit blasts in order to reduce blast vibrations whilst minimising impacts on productivity are described. Non-linear numerical modelling was used to establish the dynamic capacity of the fan chambers, and set a PPV of 250 mm/s as a threshold for damage. The numerical model captured the full dynamic behaviour of the fan chambers and installed support, including transient stresses, strains and induced damage, when subjected to a simulated open pit blast.This case study also outlines a procedure for monitoring and predicting blast vibrations at other mine sites where open pit blasting has the potential to impact on a nearby underground mine.

Nov 8, 2011

By Childs G, Ritchie IC

This paper describes the principle and operation of small hydrocyclones for use in the coal, minerals and other process industries. The principles for selecting a hydrocyclone for an application are also discussed. Typic- al uses and installations in various industries are described.

Jan 1, 1984

Designing and constructing OxianaÆs Sepon gold and copper operations in one of the most remote areas in Laos has been a great achievement; one which was recognised by the engineering industryÆs highest accolade û the Australian Engineering Excellence Award in 2005. The developing nation of Laos has no previous mining or heavy industrial experience, but the support of the Lao Government and a remarkable Lao workforce has enabled the project to be developed and operate as well as it would anywhere else in the world.When making a decision to invest offshore, several geophysical and jurisdictional criteria need to be considered. Laos offers unparalleled prospectivity, a central location with growing infrastructure, a ready workforce and a developing but supportive regulatory regime. In addition, the Sepon copper project has exceptional characteristics, including its high grades, location near the surface, leachable qualities, access to hydropower and the ability to produce cathodes on site. These attributes and its location in the centre of a region hungry for resources contributes to the projectÆs excellent economics.

Jan 1, 2006

By P J. Howard, P Darvall, J H. Mainwaring

In less than a year, Atlas Iron’s Corunna Downs Project has moved from a new discovery to a substantial resource of high quality in an underexplored greenstone belt. Located approximately 170 km south-east of Port Hedland and 40 km south-west of Marble Bar, in the Pilbara Region of Western Australia, Atlas Iron Ltd (Atlas) has conducted extensive exploration work at Split Rock, Razorback, Runway and Shark Gully, consisting of geophysical surveying, field mapping, 464 reverse circulation and 16 diamond drill holes resulting in a current resource of 51 Mt at 57.3 per cent Fe (Atlas, 2014b).The Corunna Downs Project is interpreted to be hosted within the Cleaverville Formation of the Archaean Gorge Creek Group. Within the project area these rocks outcrop as subvertically dipping banded iron-formations (BIFs) and jaspilites, cherts, minor shales and meta-sediments forming a north–south trending plateau.Primary hematite-martite iron mineralisation is overprinted in the near surface environment by supergene goethite, and frequently capped with a thin laterite cover. The strongest enrichment areas have been discovered within topographic lows, proximal to fault zones, which coincide with a geophysical anolmaly. These characteristics were targeted, and the subsequent areas mapped in greater detail, allowing for efficient resource definition.Although first explored for iron in the late 1960s, it wasn’t until Atlas’ acquisition of the project in October 2012, that major strides were made to defining an economic resource. At present, Corunna Downs is Atlas’ best greenfields exploration discovery, both in terms of the potential scale of the resource and its blending capacity.The Corunna Downs prospect is emerging as a major new iron ore province in the Pilbara and includes 80 km of potential host stratigraphy. Corunna Downs sits strategically between Atlas’ Mt Webber and McPhee Creek tenements, and can play an important part in Atlas’ growth strategy as iron ore market conditions become more volatile and challenging.CITATION:Mainwaring, J H, Howard, P J and Darvall, P, 2015. Discovery of the Corunna Downs deposits, in Proceedings Iron Ore 2015, pp 305–312 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By K J. Ward, C N. Hatton, J Scalia IV, C A. Bareither, D L. Spencer

The mining industry is experiencing change in the governance of tailings facilities (TFs). Guidance and regulations across many jurisdictions contribute to this amorphous change. The Canadian Dam Association, Mining Association of Canada, Australian National Committee on Large Dams, and the Global Industry Standard on Tailings Management, produced by the International Council on Mining and Metals, are establishing guidelines for more rigorous industry governance. Evolving guidance regarding TFs is developing concurrently with a shortage of experienced tailings engineers, which adversely affects the resource base available to support new governance. This paper presents an updated semi-quantitative estimate of the impending resource shortage of qualified tailings professionals. Updates are provided herein for the estimated number of TFs worldwide, which included available data on active and inactive TFs, as well as the estimated labor resources required to service these facilities. The tailings labor shortage is discussed in the context of academic and professional training currently available to increase the quantity of trained personnel. This paper represents a discrete moment in time as contributions to the available information and inventories accessed continue to improve, but as of today are incomplete. However, the data and information included provide insight into the resource deficiencies currently within our profession, training and education opportunities to address those resource deficiencies, and a snapshot of a recent professional training course offered on mine tailings.

Jul 1, 2021

The paper discusses the characteristics of Be-zymianny activity during the last 2500 years. Three periods of increased activity have been identified which are the eruptive cycles lasting for 100-400 yrs. The periods of high activity fall on the fol-lowing time intervals: 2400-1700 yrs ago, 1350-1000 yrs ago and from 1955 ixp to the present time. The 1955-1956 catastrophic eruption after a long period of repose (about 900-1000 yrs) opened a new cycle of activity of the volcano which is continuing to-day. Several decades are distinguished in activity which differ in character and intensity of eruptions.

Jan 1, 1990

Computer simulation of the control systems for the heavy media coal washing process have been presented in this paper. The simulation model applies the Simulink module of the Matlab 5.1 software package and allows monitoring of variations of a

Jan 1, 1998

By A E Reschke

The high-shear colloidal mixer is generally recognised as the most efficient method of mixing cement based grouts. Only recently however has this technology been applied to the production of cemented rockfill (CRF) for use in underground mines in North America. Traditionally, paddle type mixers have been used to produce the cement based slurries required for the preparation of CRF. While considerable success has been achieved with these mixers, tremendous advantages are attained with the colloidal mixer. The combined effect of the highly efficient mixing action and the ability to mix low water/solids ratios, allows for reductions in the cement content for a given strength requirement. Cement can also be replaced by cheaper fillers such as flyash, resulting in further cost savings. Although large-scale dedicated CRF hatching plants are typical, there is a growing need for mobile plants capable of operating anywhere underground. The compact size and rapid hatching speed of high-shear colloidal mixers has allowed them to be incorporated into skid mounted systems capable of producing and discharging cement based slurries onto rockfill aggregate for the production of CRF. In many cases run-of-mine development waste can be used as CRF aggregate with these slurry plants thereby reducing the cost of waste rock removal. These relatively low cost portable plants have now allowed several mines to economically rccmer isolated pillars and realise positive returns on their investment.

Jan 1, 1998

By C Aldrich

In this paper, the use of topology preserving projections (Sammon maps) and neural networks are considered as a basis for the construction of multivariate statistical process control charts for a semi-autogenous grinding circuit on a gold plant. Comminution circuits are often operated in a quasi-steady state mode, where the mills tend to move rapidly from one state to another. This makes them difficult to monitor by conventional means designed for continuous steady state processes. As a first step, process data reflecting normal operating conditions are mapped with SammonÆs algorithm. Only one feature is extracted at a time and each mapping is captured by a neural network model to allow online application. Reverse neural network models are used to reconstruct the data prior to the extraction of subsequent features from the data residuals. The ensemble of neural network models can then be used for both fault detection and identification. The approach compared favourable with both linear and non-linear principal component models. It was able to detect two simulated fault conditions both with a reliability of 100 per cent, as opposed to 57.8 per cent and 95.2 per cent detected by an approach based on the use of linear principal component analysis and 84.1 per cent and 98.0 per cent detected by an approach based on non-linear principal components extracted with auto-associative neural networks.

Jan 1, 2007

By Beeforth C. G

The use of Non-Linear Programming to obtain improved schedules of future activity in two specific cases of mining and treatment of minerals is described. The two cases were (i) reclamation of gold, uranium and sulphur from old surface tailings dams and, (ii) underground mining of gold. The method used an augmented Lagrangian device to reduce a constrained Non-Linear Programme to a sequence of unconstrained hill- climbing procedures. The main advantages of the method appear to be those of (a)flexibility of modelling of industrial characteristics and constraints and, (b) reasonably modest computation times.

Jan 1, 1977

By G Anderson, V Lawson, P Voigt

Glencore operates zinc concentrators at both Mount Isa and McArthur River. Both orebodies have a history of complexity and required the development of new technologies to maximise the value from these long-life assets. The Mount Isa orebodies were plagued since operations started in 1931 with complex mineral textures making separation challenging and many areas uneconomic. Examples are given in Figure 1 with different grain sizes from the same orebody in different areas. The McArthur River deposit, located in the Northern Territory, was discovered by Mount Isa Mines geologists in 1955 (Logan, Murray and Williams 1990). The extremely fine-grained nature of the ore was quickly recognised and the difficult separation of the minerals was soon obvious. The geographical, metallurgical and economic factors resulted in the orebody not being developed until the technologies for the mineral separation had been developed. The development of the IsaMill allowed for an economic mineral separation flowsheet to be developed and ore treatment commenced in May 1995 (Nihill, Stewart and Bowen 1998). CITATION: Lawson, V, Anderson, G and Voigt, P, 2018. Developing technologies for a complex orebody, in Proceedings Complex Orebodies Conference 2018, pp 116–118 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The fragmentation of whole rock by blasting has an influence on the subsequent loading, hauling and crushing operations. However, no method of calculating the frag- mentation has yet been developed. This paper gives a method of calculating the fragmen- tation for the simplest form of blasting, i.e. cratering. Cratering consists of the detonation of a spherical charge of explosive in a blasthole breaking to one free surface. This paper gives a method of calculating the extent of the system of radial cracks generated by the explosive in the rock. This system of radial cracks is then used to calculate the fragment size distribution curve from blasting. The calculated curves are shown to be in good agreement with experiment.

Jan 1, 1977