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By Q Zhou, J Pan, D Q. Zhu, C C. Yang

Oxidised pellets have become an indispensable high-quality charge for blast furnaces (BF) due to their uniform particle size, high iron grade, high mechanical strength, good metallurgical performance, as well as relatively low energy consumption and gaseous pollutant emissions in pellet production. Nevertheless, due to the rapid development of the global steel industry, highquality pellet feeds are becoming more and more scarce. In order to broaden the source of pellet feeds and reduce the production cost of pellets, more and more steel mills are going to use coarse iron ore fines with relatively low iron grade and low impurities for preparation of desirable pellet feeds through a typical wet grinding-settling-filtering process. In this work, the grinding, settling and filtering behaviour of Brazilian and Australian iron ore fines are studied and compared, aiming at finding out the internal relationship between the mineralogical characteristics of different iron ore types and their grinding-settling-filtering performance. The results show that the grindability is heavily dependent on the hardness of iron ores, which is governed by the mineralogical characteristics of the raw materials. Usually the higher the hardness, the more grinding energy is required. Except for Brazilian specularite, Australian hematite-goethite type iron ore fines and Brazilian hematite ore fines exhibit good grindability with a Bond Work Index of about 10–15 kW•h/t. In addition, the settling and filtering performance of ground iron ores are largely affected by the density, mineralogical characteristics of iron ore fines (eg, quantity of clay minerals and goethite and porosity of ore particles), grinding fineness, etc. Generally, iron ore fines with higher density, lower quantity of soft minerals (clay and goethite) and larger particle size give superior settling and filtering performance. For iron ore fines with inferior grinding, settling and filtering performance, applying more energy-efficient grinding techniques, blending with ore types with good settling and filtering performance can reduce grinding energy consumption and improve settling and filtration rates to maximise the productivity of equipment and lower the operational cost

Sep 18, 2023

By T Baumgartl, B Richards

The association of specific plants and plant communities with soils developed over underlying superficial orebodies and mineralisation has been long recognised. It has given rise to the use of plant indicators for geobotanical exploration as a regular component of primary minerals reconnaissance where there is an undisturbed vegetation cover. That the chemical composition of indicator plants is a measure of their soil environment has further led to biogeochemical prospecting methods for minerals and its use in the mapping of underlying ore deposits. Where there is a strong surface expression of metal and metalloid anomalies, concentrations of potentially phytotoxic elements may reach a level at which they have strong selective impacts on plant populations. In such circumstances, natural selection has operated in the development of a unique flora composed of plant species and individuals with genetically-based tolerances to the stressed environment in which they continue to survive. These plants are called metallophytes. Metallophytes occur globally on all metalliferous sites, both in pristine undisturbed environments and in areas of mineral workings, ancient and modern. However, the best-developed primary metallophyte vegetation is found in the most ancient areas where there has been a long-term evolutionary impact of the underlying geology through ore weathering and dispersion of metals into the rhizosphere zone. Natural selection of metal-tolerant races of plants in these largely undisturbed areas can eventually lead to speciation and the development of an endemic regional metallophyte flora (Baker et al , 2010). Mineral wastes resulting from mining activities also allow colonisation by metal-tolerant individuals leading to the establishment of metallophyte communities. The distribution and extent of such communities is determined by regional and local factors relating to climate and substrate conditions and the availability of suitable plant resources on which natural selection can operate (Baker, 2009).The ability of metallophytes to tolerate extreme metal concentrations commends them as the optimal choice for ecological restoration of mineral wastes and metal-contaminated sites. Metallophytes have recently also spawned several novel phytotechnologies, including phytoremediation and phytomining (Chaney et al, 2000, 2005; Baker and Whiting, 2008). Action towards conserving the global metallophyte resource base is imperative because many species are under threat of extinction from new and extensive mining activities (Whiting et al, 2004). This has been identified as a priority in the Mining, Minerals and Sustainable Development (MMSD) Project of the Global Mining Initiative in 2002 but positive responses from the minerals industry have been slow. The last decade has, however, seen an ever-increasing interest in metal-tolerant and metal-accumulating plants, both from an academic standpoint and their use in revegetation and phytostabilisation (Tordoff et al, 2000; Baker and Whiting, 2008; Baker, 2009). Few studies have highlighted the need to conserve and develop these unique plants (Whiting et al , 2004). This presentation identifies future research needs for the conservation and exploitation of the global metallophyte biodiversity and its potential in sustainable mine closure. CITATION:Baumgartl, T and Richards, B, 2012. Evaporation and salt transport under variable climatic conditions, in Proceedings Life-of-Mine 2012 , pp 179-186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By V Pfannenstiel

The United States (US) coal mining industry has been working under comprehensive planning, operating and rehabilitation regulatory requirements for nearly 35 years. The public desire for environmental protection during mining and rehabilitation following mining to achieve post-mining land use and sustainability goals has been a major factor and continues to influence the process. Mining companies have evolved operations to achieve outcomes that address the desired goals and regulatory requirements cost-effectively and successfully. Over the 35 year regulatory period, requirements for more diverse topography, specialised revegetation communities, landform stability and assured sustainability have increased and become more complex. These challenges are effectively met by maximising integration of mine planning and operating with the rehabilitation process. Rehabilitation is then implemented in a more timely and efficient manner and with effective results that achieve desired outcomes, commonly with added value. Peabody Energy (Peabody) has taken this approach in its US operations and this paper discusses an integrated approach and illustrates learnings and results with examples from several of its western US operations.CITATION:Pfannenstiel, V, 2012. Integrated planning, mining and rehabilitation for effective results and sustainable land use - A western United States perspective, in Proceedings Life-of-Mine 2012 , pp 219-232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By J Herrmann, J Richards, B Hutchison

An extensive trial of laser-based survey and monitoring systems at Hillgrove Resources Kanmantoo Copper Mine in the Adelaide Hills, South Australia, has proved the capabilities of the system in monitoring rock movements on open pit walls. Initially, the trial involved deploying a Maptek I-Site 8820 laser scanner and the proof-of-concept Maptek Sentry software in the Nugent Pit to monitor ductile rock movements located up to 260 m away. The system was proven to be capable of monitoring various rock movements from 1.5 tonne rockfalls up to a 40 m high toppling wall failure. Data collected from smaller rockfalls was used to help build a database for Hillgrove’s rockfall management program. As part of the trial, the laser scanner was deployed to monitor a ramp movement event, as well as the toppling failure, adjacent to an IBIS slope stability radar. Both devices monitored the slump and the slowly developing toppling movements, with similar results. Although the radar was used as the successful ‘critical alarm’ device for the toppling failure, post-failure analysis showed the laser-based system to be capable of performing a similar role in the ductile rock regime; albeit over much shorter distances than the radar capability. A second laser scanner was deployed to monitor Kanmantoo’s Emily Pit in early December 2014, where it successfully provided critical alarm warnings for a block topple event. Sentry software, which takes advantage of Maptek I-Site 3D spatial imaging technology, was first released in November 2014 to meet industry demand for a cost effective, flexible system to detect movement. Sentry has now been re-launched as a fully transportable monitoring system. Deployed in a custom trailer, the system offers a power and communications module, cellular and Wi-Fi networking and a stable bollard for the I-Site laser scanner and Sentry software. This paper will present rock wall movement data from the Sentry trial and a subsequent two years of monitoring of the open pit walls at the Kanmantoo Copper Mine, at distances out to 750m. In addition, examples of remote geological mapping and small rockfall detection, using the laser scans, will be described. The Sentry system has proven to be beneficial for the continual improvement of slope monitoring and risk management at hard rock mines. CITATION:Hutchison, B, Richards, J, Richards, J and Herrmann, J, 2018. Mine rockfall and rock wall failures – proven digital laser-based approach for monitoring slopes at the Kanmantoo Copper Mine, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 463–472 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

By L Nagy, K P. Juhasz

The authors were engaged to optimise a traditional rebar cage reinforced concrete segmental lining by means of finite element analysis (FEA) using macro synthetic fibres for the Shanghai metro extension. The aim of this study was to reduce or entirely replace the original steel reinforcement of the segmental lining, in order to make the precast production process faster and more economic. The outer diameter of the tunnel was 6200 mm, the thickness of the segments was 350 mm.The numerical calculations were performed by Atena Finite Element software, which is based on the combination of Menétrey-William and Rankine failure surfaces on the compression and tension sides respectively. The effect of the macro synthetic fibres was modelled as tension stiffening on the tension surface.A one-to-one full scale model of an assembled tunnel ring using the original reinforcement cages was tested at Tongji University in Shanghai, July 2013. The ring was tested to differing load levels where load and displacement were measured until failure. The author’s first step was to calculate the real displacement characteristics of the original reinforced concrete (RC) ring, then calculate the numerically modelled version, so as to compare them. The material parameters of the concrete and rebar used had been determined through basic material tests conducted at the Tongji University. (Bi, Liu and Wang, in press).The numerical modelling undertaken has shown good correlation with the full-scale physical test results. Optimisation of the lining reinforcement was achieved through the addition of fibres, resulting in a substantial reduction of the steel rebar cages. Several results have been computed with the numerical model using different dosages of macro synthetic fibres, showing that the mass of steel reinforcement could be reduced by 50 and 75 per cent respectively.CITATION:Juhasz, K P, Nagy, L and Winterberg, R, 2014. Full-round numerical modelling of a macro synthetic fibre reinforced tunnel boring machine tunnel in the Shanghai Metro extension, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 477–484 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By J Purandare, D Murdoch

The goal of the life-of-mine plan is to ensure that while the site is left safe, stable and non-polluting, the landscape is such that optimal use can be made of the site post-mining and closure. However, in the face of evolving shareholder expectations and the current international economic climate, numerous mines are ceasing operations and moving into a care and maintenance phase. These changes bring with them a high degree of community concern, not only about the potential legacy of closed operations, but also those mines that continue to operate.While mines across Australia are committed from the earliest planning stage to develop clearly defined post-mining land use and landform objectives, broader expectations related to these objectives may change and evolve during the life of the operation. This is especially the case where a mining operation has a project approval where the land use objectives are aligned to land capability and land use commensurate to that which occurred premining. CITATION:Murdoch, D and Purandare, J, 2016. Optimising land for beneficial use during and after mining, in Proceedings Life-of-Mine 2016 Conference, pp 166–167 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By K Cameron, S Strohmayr, J Wallace

In 2012, a single module heavy medium cyclone plant (HMP) was installed at the Glencore Zinc’s (then Xstrata Zinc) McArthur River lead zinc mine. The HMP formed the first part of the MRM Phase 3 Project to increase run of mine (ROM) capacity from 2.4 to 5.5 Mt/a.The purpose of the HMP is to remove liberated gangue from the crusher product at minimal loss of valuable mineral. The McArthur ores are very finely disseminated requiring a fine primary grind size prior to rougher flotation. Rejecting waste prior to grinding therefore offers significant power and grinding media savings. The plant was designed to treat only those ores with a reasonable upgrade ratio at the target zinc recovery across the HMP of 95%.On this basis, a 1.8 Mt/a single module plant was built based on 250 t/h feed rate and 82% availability. In contrast to existing base metal heavy medium plants in Australia, the MRM Flow sheet utilised the principles in modern coal heavy medium cyclone plant design. Since commissioning, the plant feed rate has been significantly increased and is now normally operated up to 540 t/h (dry basis).Although this throughput increase is partially due to debottlenecking work, it is also attributable to the conservative design parameters for base metal heavy medium cyclone circuits in comparison to those used in equivalent coal circuits.This paper discusses Flow sheet design and compares traditional base metal design parameters with those achieved at MRM and those of modern coal plants. It provides information on plant capital and operating costs and the net savings realised by its installation. In addition to power and grinding cost savings, the paper also highlights the savings in water through rejection of near dry waste and reduction of tailings pumped to the storage dam.CITATION:Wallace, J, Strohmayr, S and Cameron, K, 2015. McArthur River Mine heavy medium plant – the benefits of applying modern coal plant design principles to base metal heavy medium separation, in Proceedings MetPlant 2015, pp 311–323 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

Although mining, particularly of gold and coal, played a significant role in the development of New Zealand, from the time of the spectacular gold rushes of the 1860s its economic importance to the country as a whole has decreased substantially since that time. Gold, coal and non-metallic agricultural and industrial minerals have been found in economically significant quantities, however, the search for base metals has not been successful.

Jan 1, 1982

By R M. Lonsdale, M D. Goodz

"With an ever-increasing dynamic business environment, successful stakeholder engagement is becoming more fundamental to achieving desired outcomes in today’s mineral resource industries. It is imperative to be proactive in correctly identifying all stakeholders and initiating early contact. This builds trust relationships, which are essential to ensure future decision-making processes are streamlined.Often neglected is a company’s obligation to select the correct team to represent its values and mission. The company requires representation that demonstrates an understanding and commitment to its operations and people, the safety and health of the community and environment, and most importantly, represents the decision makers. Stakeholders need to believe that the engagement process is genuine and that the company representatives are aligned towards targeted outcomes that will benefit all stakeholders in some way.Among others, stakeholders include shareholders, staff, families, community, service and supply providers, regulators, land managers and the political/financial framework. Depending upon the mineral product, stakeholders may include ports, international offtake clients and those along the route. New stakeholders continually evolve during mine life, and the engagement process requires an investor–community–public relations (IR/CR/PR) team to anticipate change and actively scan perception and chatter.Successful communication is more than delivering a message; it is about engaging stakeholders and confirming the feedback loop to ensure the correct message is communicated and the relationship is strengthened.The nature of the mining company’s branding and the public’s perception of company intentions will dictate whether there is willingness to allow the company to follow its desired path. This in turn controls the company’s most scarce resource – time. Timing is fundamental to achieving targeted outcomes with minimal cost and delays, marketing in a peak cycle and acquiring critical capital for development and growth.Branding and stakeholder engagement effectively controls and extends to the company its social licence to operate.CITATION:Goodz, M D and Lonsdale, R M, 2016. Stakeholder engagement – who are you, what do you stand for and why? In Proceedings International Mine Management Conference, pp 239-248 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 22, 2016

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

By E Hondros

Innovation and Business Skills Australia (IBSA) commissioned The Boston Consulting Group (BCG) to undertake a study into how the role of AustraliaÆs senior managers is likely to change between now and 2020 and to identify the skills and attributes that will be needed to respond to those changes. This report builds on a previous study prepared by BCG in the early 1990s for the Industry Taskforce on Leadership and Management Skills (Karpin Committee), which provided a snapshot of the Senior Manager in 2010. The following powerpoint slides summarise the 2020 Vision û The Manager of the 21st Century û outlining how the role of AustraliaÆs senior managers is likely to change between now and 2020 and to identify the skills and attributes that will be needed to respond to those changes. The presentation is summed up in the following quote from Jon Nicholson û Senior Vice President of BCG: We believe that to succeed in the years up to 2020, executives will need to master a range of hard and soft skills. Amongst other things, they will require to manage multi-generaional teams, the creativity to measure staff performance on outputs rather than inputs, and a high degree of technical and functional expertise in addition to their general management credentials. This paper is available as a PowerPoint presentation only.

Jan 1, 2006

By J J. J Chen, J C. Zhao

A water/air model was developed to simulate the refining of molten aluminium by the sparging of gas through an impeller. The optimal gas dispersion depends upon selecting the correct gas rate for a given impeller rotational velocity to prevent flooding or channelling. Correlations illustrating this flooding behaviour exist for standard impellers within standard tank geometries. However the validity of these correlations has not been substantiated for gas dispersion in high temperature molten metals with non-standard tank and impeller dimensions. Metal refining is most efficient when fine bubbles are generated and uniformly distributed within the treatment tank. The application of some measuring technique able to detect this distribution within a non transparent operating treatment tank would be invaluable, enabling the optimisation of gas flow and impeller speed.   A technique has been developed to measure the pressure fluctuation levels at specific points in the water model. Comparison of these pressure fluctuation data with photographic evidence obtained in the water model suggests that the flow regime in the metal treatment unit may be determined using this technique.

Jan 1, 1995

By E Nik, A Manzoori, H Namavari, P Witt

The smelter building at Sarcheshmeh Copper Complex, Iran, houses two reverberatory furnaces and five Pierce-Smith converters. Under normal operating conditions SO2 emissions fill the building, posing a major health problem for all workers in the building, and reducing their ability to maintain the plant. The converter fume extraction system was analysed using plant measurements, engineering modelling of the entire system and CFD modelling of the extraction hoods. By applying fundamental engineering concepts, a user-interactive computer program was developed that enabled plant engineers and operators to gain a detailed understanding of the system. In conjunction with plant measurements, the model quantified the amount of inleakage throughout the system, identifying it as a significant contributor to the poor extraction performance. Furthermore, it enabled investigation of the effects of hood gates, converters on line, hood dampers, flue insulation, electrostatic precipitator (ESP) operation, and inclusion of an acid plant. The model gave unprecedented insight into the operation of a counterintuitive buoyancy-driven extraction system.

Jan 1, 2004

By M Hassall

There is a plethora of activities that have been, and continue to be, performed to improve the health, safety and well-being of workers involved in resource industry activities. These activities include implementation of risk management systems, performing risk assessments, constructing bow-ties, implementing critical control management systems, undertaking personal, process and functional safety initiatives, implementing psychological and physical health as well as industrial hygiene programs. Despite the significant work that has occurred over the last several decades, unacceptable levels of fatalities, injuries and illnesses continue to persist as evidenced by Safe Work Australia statistics.

Apr 16, 2024

By J J. L du Plessis, S Viviers, G Ratner

Escalating electricity costs are one of the biggest operational cost drivers in mining. The trend to use high-powered auxiliary fans delivering increased airflow to meet the dilution requirements of diesel equipment, together with the reliance on ducted systems rather than traditional flow-through systems to ventilate areas, increases the overall energy requirements of ventilation systems. To manage and reduce electricity costs energy management systems can be implemented, inefficient operating units can be replaced and the operation of energy-consuming components of ventilation systems can be optimised.This paper describes the process followed to design and develop an energy-efficient axial flow auxiliary fan. The fan-targeted design was based on static pressure and volume flow rate requirements incorporating higher overall fan efficiencies. A brief overview of the results is given, including the aerodynamic design procedure using computational fluid dynamic (CFD) analysis. The mechanical design criteria used, including stress analysis on the rotor and designs to improve the vibration levels of the fan, are also presented. Through this study it was demonstrated that the aerodynamically designed rotors using profiled and twisted blades improve the total fan efficiency considerably when compared with some of the older-generation fans using cambered plates. The latter were typical in the mining sector in South Africa at the time of the study where average overall fan efficiencies of standard cambered fans less than 63 per cent and some of the older-generation cast aluminium blades have peak overall fan efficiencies of about 65 per cent. Peak overall fan efficiency of more than 80 per cent was achieved by using the described design and development process. Additional benefits are that the fans are quieter due to the better aerodynamic design and have a longer operating life due to reduced vibration levels.In conclusion, the use of CFD to develop fans to deliver the required volume flow at the required pressure allows quicker design turnaround time. It furthermore allows the ventilation engineer the option to specify a specific fan and is not limited to an off-the-shelf catalogue fan. It thus allows engineers to purchase a fit-for-purpose energy-efficient fan. The introduction of reliable fan control systems may, however, still result in the biggest cost benefit for underground mines.CITATION:du Plessis, J J L, Ratner, G and Viviers, S, 2015. Design and development of energy-efficient secondary axial flow fans, in Proceedings The Australian Mine Ventilation Conference, pp 337–344 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By T Christie

Tertiary volcanic rocks make up a significant proportion of the surficial cover rocks of New Zealand, especially in the Taupo Volcanic Zone. Industrial minerals that are associated with or derived from the volcanic rocks include: amorphous silica, allophane, bentonite, diatomite, ignimbrite building stone, illite clays, halloysite clay, obsidian, perlite, pumice, sulphur, titanomagnetite ironsand and zeolite. Of these: bentonite, ignimbrite building stone, perlite, pumice and titanomagnetite ironsand have been mined and processed for 20 to 30 years, but many of the others require further characterisation of the resource and/or development of markets.   We have compiled interim mineral deposit models for halloysite clays in rhyolite and for zeolites in altered vitric tuffs. These models include geological and mineralogical attributes, which are linked to the underlying volcanic and geothermal processes that have produced the minerals and their source volcanic rocks. Halloysite clay deposits at Matauri Bay (Northland) have formed from hydrothermal alteration and weathering of rhyolite. Clinoptilolite + mordenite zeolite deposits in the Ngakuru area (Rotorua district) have formed from hydrothermal alteration of volcanic glass in lacustrine sediments and ignimbrite. Further refinement and application of these models will result in a better understanding of the mineralogy, localisation and origin of the deposits, with consequent applications in exploration and resource assessments.

Jan 1, 2001

By R Marchant, D Willingham

"Predictive maintenance (also known as PHM or equipment ‘health monitoring’) refers to the intelligent monitoring of equipment to avoid future equipment failures. In contrast to conventional preventive maintenance, the maintenance schedule is not determined by a prescribed timeline; instead, it is determined by analytic algorithms, such as machine learning, using data collected from equipment sensors and/or via simulation.Predictive maintenance offers the following benefits for operators and equipment manufacturers:reduction of equipment downtime by identifying issues before failure, thereby enabling convenient scheduling of equipment service and extending equipment lifetimeautomatic determination of the root cause of the failure, enabling appropriate service to be performed without utilising resources to determine a diagnosis avoidance of costs of unnecessary maintenance and unexpected failures improved safety and product quality.Algorithms and data are critical to predictive maintenance success. Sensor data preprocessing is performed using advanced statistical and signal processing techniques. In the case that data isn’t available for the full range of operating modes, operating scenarios can be simulated. Machine learning techniques are then used to estimate equipment health. Once tested, predictive maintenance algorithms may be operationalised in an IT environment such as a server or cloud. Alternatively, algorithms may be implemented in an embedded system directly on the equipment, allowing for faster response times and significantly reducing the amount of data sent over the network.In this paper, we use both historical and simulated data of the plant under various modes of operation including run to failure, and we then leverage machine learning techniques in MATLAB to estimate degradation and remaining useful life. This technique, of combining both simulation models and machine learning, in the areas of predictive maintenance and equipment health monitoring has been adopted by Safran, makers of aircraft jet engines, since 2007. They now have over 160 modules developed (Lacaille and Aurelie, 2015).Citation:Willingham, D and Marchant, R, 2016. Predictive Maintenance Using Simulation and Machine Learning, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 279–284 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

The Barmac autogenous crushing mill is one of the most successful new comminution technologies to become available to the mining and industrial minerals industries in this decade.   The Barmac autogenous crushing mill is an innovative Vertical Shaft Impactor which operates in essence like a high intensity dry ore centrifugal pump with the reduction occurring primarily as a result of high velocity rock to rock impact in a fully rock lined crushing chamber.   With applications in a wide range of mining and industrial minerals operations the Barmac autogenous crushing mill presents an opportunity to enhance reduction and liberation whilst providing many cost savings and production increases in new and existing plants.   This paper briefly describes the operation of the Barmac autogenous crushing mill and reviews its benefits.

Jan 1, 1990

By X Qiu

According to the temporal and spatial distribution of regional metallogenesis, thePacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinental metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly related to S-type granite of crustal source that was generated by collisional orogeny combined with oceanic subduction in intracontinental and continental margin settings. Based on the concept of metallogenetic series, there is a group of mineralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metallogenetic series are widely distributed in the Asia-Australia W-Sn metallogenetic belt, and are well developed in Southeast China. Five metallogenetic series and two petro-minerogenesis evolution models have been established according to their tectonic settings, various types of granitoids and metallogenetic evolution.

Jan 1, 1995

By Colston M. B, Johnson I. D

The importance which matters of social welfare and environmental quality have assumed recently is the underlying theme of this paper. Demands for infrastructure reflect the change in emphasis from economic and technological development to those issues which affect the total well-being of the community. To put the importance of social change in perspective, examples are cited and a theme is developed which underlines the relevance of changes in public attitude and in government policies on mineral exploitation and related development and on the regimen of associated infrastructure sought. Planning on a long term or strategic basis and on a broad scale is put forward as an effective means of identifying changing social attitudes for the purpose of framing government and corporate policies. As a prelude to a section in which a description is given of a novel 'services baseline' concept and its use in the assessment of the current backlog of services

Jan 1, 1977