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By H Haghighi

Haul roads are often permanent unsealed access roads used by heavy haul trucks to transfer minerals. These roads can deteriorate rapidly which results in potholes, deformations and dust. Downer EDI Works has successfully provided efficient solutions to the mining industry to maintain their haul roads. HaulPac as a solution package is a process in which a bituminous emulsion is used to create a stable and durable pavement. The emulsion penetrates the road and binds the particles together, creating a stable base. It also seals the surface and prevents water from penetrating the underneath layers. Bituminous emulsion can increase the strength of the pavement material and decrease the road surface degradation which results in dust suppression. However, the everincreasing price of commodities, the necessity of reducing carbon emissions and the increasing use of autonomous haul trucks have made it vital to invest in novel maintenance solutions that can meet the needs of the mining industry in a cost-effective manner. This paper outlines the benefits of bituminous emulsion in terms of productivity, safety and environment followed by Downer’s approach to evaluate the suitability and to optimise the amount of product. The potential for changing the colour of the treated surface is explored and an initiative that incorporates end-of-life tyres of haul trucks into the pavement is introduced. And finally, an innovative method using artificial intelligence to estimate dust emission is presented.

Sep 18, 2023

By S M. Stewart

Building and Maintaining Community Relationships   In mining terms, the town of Waihi is distinctive with the Martha mine situated right in the heart of the town. MarthaÆs central location and other mining activity nearby means there is an increased community focus on the happenings at the mine and the effects and impacts of mining. While WaihiÆs proximity to the mine is unique, all mines have a community context that they operate within.   Issues of proximity simply heighten awareness and emphasise the need for building and maintaining good community relationships. In the three years we have been working alongside the Waihi community, we have worked together with concerned and supportive residents, representatives of Newmont Waihi Gold and representatives of Hauraki District Council, to develop a collaborative framework for addressing the economic, social, environmental, cultural and spiritual wellbeing of the people of Waihi. This could not have occurred without the genuine commitment of all participants.   This collaborative focus has resulted in some tangible progress in Waihi which, in part, stems from people taking an interest in the town because the town is taking an interest in itself. As we have worked and learned within the process of building and maintaining a collaborative and sustainable community environment, we have tried to adhere to a philosophy and a set of basic principles. We believe that this approach, combined with a teachable skill set, helped to create the opportunity to develop a truly collaborative community environment which continues to grow. Our paper will describe this philosophy, these principles and the skill set that we have applied.   The application of the process in Waihi has resulted in a series of outcomes unique to Waihi. These outcomes include formation of the Waihi Community Vision committee, the Vision Waihi Trust and the subgroups set up to further the interests of particular groups, for the collective benefit of all the community.   Based on our experience of other situations, and on the way the Waihi process has developed, we believe that the identified principles and skills can be transported and used in other cultures and contexts. While the resultant outcomes may differ, the underlying principles will still apply. Progress will come from creating a sustainable environment within which the community (including residents, industry and regulatory authority) can determine its own internal relationships and the vibrant growing sense it has of itself.

Jan 1, 2006

The Horn Island gold and mineral field produced 194 kilograms of gold in the 4 years subsequent to its discovery in 1894, from an area of shallow workings 1.5 kilometres x 0.5 kilometres. Gold deposits in the adjacent Prince of Wales, Hammond and Possession Islands also drew attention at that time.These islands form part of a Carboniferous sequence of ignimbrites (Torres Strait Volcanics) intruded by the Badu Granite and minor volcanics within the Cape York-Oriomo Ridge. Gold is associated with the epithermal stages of igneous activity. Recent exploration has defined sub-horizontal zones of disseminated gold mineralisation in the sub-surface, as well as reserves in the outcropping sub-vertical structures mined in the past. Released estimates of 170,00 tonnes proven ore and 550,000 probable ore at 4 grams per tonne gold, have been established.Gold is mostly contained in quartz vein stockworks and hydrothermal breccias within the intensely propylitised medium grained granites which form the local host rocks within the coarse grained Badu Granite. Associated vein minerals are sulphides (primarily of lead, zinc and iron) and calcite. Various intrusions of porphyry, aplite and granodiorite occur through the prospect area.

Jan 1, 1986

Confirmation that acid drainage (AD) was a significant environmental issue for the Australian minerals industry came in 1992 with the first national workshop on the topic. Subsequently the extent of AD was documented in a national survey published in 1997. The recommendations arising out of that survey served as a platform for actions by government, industry and industry-support organisations such as the Australian Centre for Mining Environmental Research (ACMER) to enable more effective prevention and management of AD. This paper briefly documents the extent of AD in the industry, the government regulations and guidelines for AD management, industry initiatives, the role of ACMER and other organisations in assisting industry through research and technology transfer, and the efforts being made to deal with AD at derelict mines. Future management of AD in the industry will be assisted by the linkage of Australia (through ACMER) into the International Network for Acid Prevention (INAP) which is facilitating the interchange of knowledge on AD as well as coordinating global research on the topic.

Jan 1, 2003

By T Baumgartl, R I. Maczkowiack, O White, P D. Erskine

Queensland legislation, industry codes and policies relating to mine rehabilitation and closure create the expectation of successful progressive rehabilitation and that the post-mining environment is being returned to a condition suited to a pre-agreed, beneficial end use. Yet none of the rehabilitated mined land in the Bowen Basin has been certified as successful by authorities suggesting there is a gap between current rehabilitation and the full environmental outcomes that the legislation could deliver. We tested the veracity of this perspective and reflect on where responsibility for any discrepancy lies.We first reviewed current Queensland legislation and industry codes relating to stakeholder engagement, rehabilitation, closure planning and post-mining land use. We tested the accessibility of the documentation trail for several recent coal-mining projects in the Bowen Basin and examined the level of detail in approval documentation. We then assessed the rehabilitation performance reports of these mines in relation to the contents of their approval documents. Legislation, guidelines and codes repeatedly emphasise the need to plan for closure before mine operations begin and to progressively perform rehabilitation with an agreed end-use in mind. Early stakeholder involvement in these processes and transparency of actions and outcomes are also encouraged by government publications. Overall, in terms of transparency, we found that relevant documents are generally available to the persistent enquirer. However, the rehabilitation and closure undertakings given in both mine company and regulator documentation were commonly generic and rehabilitation obligations were not explicitly incorporated into rehabilitation plans. Rehabilitation reporting was also weak in that no distinction is required between successful and unsuccessful revegetation, nor to closure objectives and mine completion criteria. Responsibility for the apparent disconnect between regulatory intent and actual performance appears to begin with the regulator too readily allowing generic information and in not requiring performance reporting to correspond with approved post-mine conditions. As a result, companies may have a much greater rehabilitation and closure risk than mine management expects. More poignantly, the checks and balances that are in the legislation are not yielding the environmental outcomes of which they are capable.CITATION:White, O, Maczkowiack, R I, Erskine, P D and Baumgartl, T, 2012. Walk or talk - Is the current mine approval process in Queensland delivering rehabilitation and closure success?, in Proceedings Life-of-Mine 2012 , pp 59-68 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

Permeability and fluid pathways in fracture-controlled hydrothermal systems are governed by a dynamic competition between permeability-creation processes and permeability-destruction processes. Permeability evolution is coupled with the evolution of fluid pressure and stress states. Key permeability-creation processes are micro-scale to macroscopic fracture growth, and the generation of damage zones during co-seismic slip on faults or aseismic creep on faults and shear zones. The competing permeability-destruction processes include crack-healing and sealing, compaction and pore cementation. High rates of permeability destruction in hydrothermal systems require ongoing permeability enhancement to sustain high fluid fluxes and ore genesis.   In aseismic regimes, competition between permeability-creation processes and permeability-destruction processes can lead to continuous flow in deep level hydrothermal systems. However, in seismogenic regimes, rapid co-seismic permeability-enhancement is followed by progressive permeability-destruction in the intervening interseismic periods, and leads to episodic flow. The results of high pressure experiments are used to illustrate how pore fluid factors and stress states are dynamically coupled with permeability evolution in hydrothermal regimes. Particularly in the seismogenic mid- to upper crust, large changes in permeability during the seismic cycle govern relative rates of change of fluid pressure around active faults and shear zones. Rapid, post-seismic recovery of pore fluid pressures, relative to rates of shear stress recovery, leads to growth of hydrofracture networks prior to successive fault rupture events.   Pre-rupture hydrofracture networks do not develop where post-rupture fluid pressure recovery is modest relative shear stress recovery. At elevated temperatures, low rates of pore fluid pressure recovery relative to shear stress recovery promote ductile shear failure and grain-scale permeability enhancement within shear zones prior to rupture events.   The influence of pore fluid pressure cycling, shear stress cycling, and deformation processes in controlling the evolution of permeability, flow localisation, and flow anisotropy at the deposit scale are illustrated for mesothermal and epithermal lode gold systems.

Jan 1, 2005

This paper describes a mine truck hauling process called "Truck Jigging" which is currently the subject of a process patent application.The investigation explores the production and cost advantages of using the potential energy available in a descending haul truck to assist in elevating an ascending vehicle. Applications are studied for both strip cut mines and open pit operations. Various mechanical connections between the two vehicles are considered, based on a pulley mounted rope system. Fifteen year operating cost estimates show savings of up to 26.5 percent over conventional mine truck operations.

Jan 1, 1989

By L Abrahamsson

This paper describes results from a gender study for a new mine in Pajala, a small community in northern Sweden. Using a gender perspective, the study examines migration, education, local culture, the labour market, and work organisation as problems and opportunities in the regional context for the planned mine. The most obvious ‘gender issue’ for the Swedish mining industry is the very low percentage of employed women, which is even lower among mining workers. To recruit the best people, a company actively needs to attract both women and men; however, the mining companies find it difficult to recruit women as cultural, labour market and educational traditions as well as the mining companies’ own cultures often make it difficult for women to find work in the mining industry.The Torneå river valley, the region surrounding Pajala, has a gender-segregated labour market and gender-stereotyped culture and few young women live in this traditional and oldish region. Many young people leave the region and this is especially true for women. Compared to the rest of Sweden, there is a low educational level, especially among the men. In the mining companies, as in many other male homosocial workplaces, the workplace culture has strong connections to a certain type of traditional masculinity (laddishness, a kind of ‘macho-style’) and for a long time this has excluded women. ‘Gender’, however, is not only a question of recruiting women to a male-dominated industry. An organisation that discriminates according to gender can become inflexible, hindering communication, learning, innovations and change processes. In mining companies, this can manifest itself in hesitant attitudes among the miners about safety as well as organisational and technological development.This study found that companies establishing a presence in this region should develop a strategy for how to deal with and manage the risks and opportunities in the surrounding society (the regional culture) as well as inside the company (the mining culture). This need to be strategic will also be required of future mining companies as they will face higher demands on safety, gender equality, and technology to become modern, efficient and lean organisations.

Nov 22, 2011

By R Cunningham

The E26 Lift 1 North Project took 37 months from the approval on 1st January 2019 to the commencement of production on 1st March 2022. This was five months ahead of the feasibility plan. When compared to the previous E48 Block Cave construction 12 years prior, which was of a similar size and design with ten extraction drives, crusher and conveyors, the E26 Lift 1 North project has been delivered at 29 per cent less capital cost. Key metrics achieved by the project include 12.7 km of development, 240 km of production drilling for drawbells and undercut blasting, 107 drawbells fired ready for production as well as only three Lost Time Injuries compared to 16 during E48 construction. The Lift 1 North Project Team has established a significant point of difference with the delivery being completed by the ‘Owners Team Model’ not Lump Sum or Turn-key. E26 Lift 1 North is now supplying the Northparkes processing plant for the next eight years. This paper discusses major milestones achieved throughout the process, modifications to processes from previous block cave construction at Northparkes as well as novel approaches to work to achieve the successful delivery of the project.

Mar 29, 2023

By Francis R. S, Campbell J. J

Aberfoyle's Hellyer Division has filtered very fine flotation concentrates using two different makes of pressure filter. At the Luina concentrator a Larox pressure filter was used to treat a combined Pb + Zn or bulk concentrate. At the Hellyer concentrator two Lasta pressure filters are being used to filter copper/silver, lead, zinc and bulk concentrates. Operating parameters and performance at both operations are described. In both concentrators it was found that correct cloth selection was critical and that cloth failures contributed significantly to downtime. Thorough preventative maintenance progammes were required to ensure adequate availability of both makes of filter.

Jan 1, 1989

The long-term production schedule of open pit mines that maximises the net present value (NPV) of a given project relies on the proper design of phases (pushbacks) within the ultimate pit limits. There is not a phase design algorithm applied in the mining industry today that gives yearly production schedules that are optimum.The majority of phase design algorithms currently in use by the mining industry aims at grouping the blocks that fall within the ultimate pit limits into phases such that the average value of the blocks within each phase decrease as the size of the phases increase. Current phase design methods are typically based on a pit limit optimisation algorithm, originally introduced by Lerchs and Grossmann (LG) in 1965. To obtain multiple pit shells to be used for the phase design, the LG pit limit algorithm successively applied to economic block models by changing the price of the commodity or some other factor that properly parameterises the size of the pit. These modified economic block models are developed by predetermining the destination for each block in the model based on a breakeven analysis and highest economic outcome between alternative destinations. Phase designs determined by these existing algorithms may be suboptimal if a given project utilises multiple processing facilities for metal recovery and particularly if these facilities have restrictions (constraints) that require blending of attributes in the feed. To overcome these problems in obtaining phases that optimise overall production schedules, a new algorithm is developed at the Colorado School of Mines. The algorithm determines the phases of an open pit mine by taking into account multiple process options for the blocks and period by period blending requirements. This algorithm has been implemented within a software program (the software) and is being prototyped successfully in the design of improved pushbacks at a copper mine in South America and on a gold mine in Nevada. This presentation will demonstrate the shortcomings of the traditional phase design methodologies based on comparison of results coming from the new approach versus the traditional.

Dec 6, 2010

By W Baguley

Attritioning has been a method of improving mineral extraction for over 60 years, however it is only recently that an understanding of the mechanism employed and the improvement in efficiency that have been achieved.The paper will discuss these improvements and how to overcome the problems that have been raised. At present there is a dearth of information on the correct design and operation of these machines.The paper will address these issues as well as fluid on the Zeta potential, micro shear, retention residence time and pilot plant operation.A study on the hydrodynamics of attritioner operation has been identified and will be discussed.Surface chemistry, clean lines of attrition material and the treatment of fines significant advances in the understanding of attritioning highlighted.CITATION:Baguley, W, 2013. Attrition scrubbers, in Proceedings MetPlant 2013 , pp 229-246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By Secis R

Northparkes Mines is located 27 km northwest of Parkes in central west New South Wales. The E26 deposit is the largest of all defined to-date in the area, containing over 50 per cent of Northparkes' resources and reserves. The combination of orebody geometry and geotechnical characteristics provide ideal conditions for the block cave method of mining of the first lift of the E26 deposit. Although this method of underground mining has been used for decades in other countries, E26 is the first example of its use in Australia. Copper-gold mineralisation at Northparkes is related to quartz monzonite porphyries that have intruded coeval Ordovician volcanics. Sulphide mineralisation (dominantly bornite and chalcopyrite) occurs principally within quartz veins associated with the porphyry intrusions. Veining and mineralisation occurs within both the porphyries and volcanics. To optimise the recovery of a resource within a block cave mine, a good understanding of the rock mass and ore flow characteristics is essential. These have a significant effect on the fragmentation size and range and on parameters such as the drawzone spacing, height of interaction zone and dilution entry. As ore within a cave column moves and mixes when material is extracted from below and beside it, the total reserve extracted is unique for a particular draw strategy/production history. Until recently, reserve estimates and production schedules were based on the application of a uniform dilution factor to the tabulated resource. However, given the complicated flow and mixing within the cave column, such a simplistic approach can produce erroneous results. Northparkes Mines purchased and sponsored the upgrading of a commercially available software package specifically developed for modelling removal of resource blocks under caving conditions. This Gemcom software package, PC-BC, has been used for mine planning, reserve reporting and production scheduling. Blocks within it resource block model are converted into a mineable reserve taking into account mixing and dilution during depletion of drawcolumns (by horizontal and vertical redistribution of insitu tonnage and metal). As PC-BC gives individual drawpoint reserves, it can be used during the planning stage to determine whether or not a drawpoint is economic. For E26 Lift I an optimal layout containing 130 drawpoints has been developed based on a nominal 14 m x 14 m drawpoint spacing and a 0.8 per cent equivalent copper (eCu) cut-off grade. Annual production schedules for the depletion of material above this layout are based on: I higher tonnage removal from higher grade drawpoints in the early years of production; and 2 drawpoint production rates proportional to the total tonnage of orr remaining in the drawcolumn up to the optimal height of draw tier subsequent years. The reserve is tabulated from the combined annual production schedules over the life of the lift. The pre-mining reserve for Lift I of E26 is 26.6 Mt at 1.43 per cent copper and 0.39 g/t gold, of which approximately 23.4 Mt will be extracted under caving conditions. By scaling down the annual production schedule, weekly drawpoint tonnage calls can be given for short-tern production scheduling.

Jan 1, 1997

By Alichurch P. D

Perseverance nickel deposit is located at latitude 27¦ 491S, longitude 1200 42'E, 330 km north of Kalgoorlie, Western Australia. Gossanous outcrops were discovered in April, 1971, and after further detailed surface investigations, percussion drilling led to diamond drilling by June, 1971. Up to December, 1972, 127 diamond holes totalling 45,590 m were drilled to indicate 33 million tonnes averaging 2.2% Ni using a 1% cut-off grade. The deposit occurs in a lenticular ultra- mafic unit emplaced in metasediments locally forming the eastern flank of the Archaean green- stone belt trending NNW from Leonora to Wiluna. To the east a major strike fault separates the metasediments from gneiss; westwards there is a sequence of metavolcanics with further ultra- mafic units. Length of the lens is 3500 m and it attains a maximum width of 800 In. The eastern contact is moderately regular, but the western contact is prominently embayed. Local strikes are NNW, and dips are steeply W. A set of strike faults cuts the ultramafics and enveloping quartzites. These are normal faults, parallel to the major eastern fault, dipping 65-70¦W. They impart a serrated pat- tern to the sub-outcrop of the western contact. Massive serpentinite is the dominant rock in

Jan 1, 1973

By I Thomson, L D. Black, R G. Boutilier

The social license to operate (SLO) began as a metaphor for the ability of communities to stop mining projects. Soon people began to speak of levels of social license and the ability of communities to raise costs without completely stopping exploration or mining activities. Today the concept has spread to other industries and is evolving towards becoming a general management perspective on the socio-political rights and responsibilities of the corporation. The business case underpinning the SLO perspective on management is the need to assess and manage socio-political risk. For mining companies, socio-political risk has been steadily rising for several reasons, including the efforts of non-government organisations (NGOs) to pre-empt government policy options; the entry of mining companies into jurisdictions weak in the rule of law; and the weakness of global economic and financial regulation. In this perilous world beyond the comfort zone of effective government, mining companies must build their own socio-political stability by engaging directly with stakeholders to develop a strong SLO. In order to become a practical management perspective, the SLO needs to be measurable, which amounts to measuring the socio-political risks and opportunities presented by stakeholders. We present the results of efforts since 2009 to develop a globally reliable and valid measurement tool at the project and industry levels, validated in studies in Australia, Bolivia, Mexico and the USA. A factor analysis suggested four factors that mine management can address to raise their SLO level. The most chronically neglected factor involves the political right of the corporation to foster more equitable social contracts locally and regionally in both developed and developing countries. We conclude with recommended steps to earn and maintain the social license at the project and industry levels.CITATION:Boutilier, R G, Black, L D and Thomson, I, 2012. From metaphor to management tool - How the social license to operate can stabilise the socio-political environment for business, in Proceedings International Mine Management 2012, pp 227-238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By Hale Y. M

Multielement reconnaissance geochemistry coupled with ground scintillation gamma ray measurements has been used to investigate the dispersion patterns of uranium and other major and trace elements in the arid Palmyrides region of central Syria. This region occupies an interplatform depression in the northern part of the Arabia Plate, upon which sediments up to 10 km thick have accumulated. Outcrops of strongly fractured Mesozoic and Cenozoic rocks form two major mountain belts, the northern and southern Palmyrides, between which is located the closed Ad-Daww basin, with a thick Neogene and Quaternary clastic cover. Among the various lithologies, phosphorites are well represented. Uranium and associated elements have been incorporated into the Upper Cretaceous and Lower Palaeogene sediments, especially the phosphorites, which are well represented in the region. These elements are derived from three possible sources, namely, sea water, Lower Cretaceous volcanism and metalliferous fluids leaking along taphrogenic lineaments. In and around the phosphorites, numerous traces of secondary uranium mineralization occur. Over 500 geochemical samples of outcropping rock, wadi and playa sediments, overburden and groundwaters were taken over an area of approximately 9000 sq km. Most samples were analyzed for 25 major and trace elements by nebulization ICPAES; for As, Sb, Bi and Se by hydride generation and ICPAES; and for U, Th and La and other REE by neutron activation analysis.

Jan 1, 1988

Both here and in Australia, the unique commercial and tax features of joint venture are finding favour in forestry, fishing, technology and infrastructure projects. For New Zealand mining companies, joint ventures provide a means of access to foreign know how and investment funds, while retaining their corporate independence and their hard-earned tax losses.   This paper discusses some of the practical income tax and GST considerations where a joint venture structure is contemplated. The first part of the paper considers income tax, and in particular how joint ventures enable companies to access and carry forward tax losses. It explains why a joint venture may be advantageous relative to a jointly owned company.   The second part of the paper concerns GST and the focus is on two aspects: 1.   Joint ventures may be registered for GST. In some instances they have no choice and are required to do so. Where a joint venture is registered in respect of a taxable activity, the members are not permitted to register in respect of the same activity. This may be problem where the member has incurred its own expenses and the member wishes to register in its own right to claim back the GST on those expenses. This paper explores the issue and possible solutions. 2.   It is not uncommon to see joint ventures claiming GST on the costs of production, and the production being sold (and GST is being charged) by the members. In this paper we consider whether these arrangements have a tax risk, and what can be done to make them technically sound.

Jan 1, 2005

By S Watson, L Martinez

Mine projects are complex opportunities that demand a constant assessment of uncertainty, ie risk and upside potential. This is because the value of a mine project is typically influenced by many underlying economic and physical uncertainties, such as metal/mineral prices, metal/mineral grades, costs, schedules, quantities, and environmental issues, amongst others, which are not known with much certainty at the beginning of the project. But, is uncertainty an enemy or an ally of the mine planner/analyst? To answer this question, this paper first assesses and elaborates upon the general concept of uncertainty. It then looks at the different sources of uncertainty in a mining project, such as the orebody, costs and product price uncertainties, and their effect on the final project value. Next, a general?review?of current mine evaluation techniques highlighting their limitations when dealing with uncertainty is made. Finally, an extended evaluation and risk management framework that addresses the existing uncertainty in the (greenfield/brownfield) mine evaluation process is proposed. One important characteristic of this framework is that it uses and manages uncertainty in order to generate additional value to the project; this is done through operational and managerial flexibility, which allow mine planners to minimise/maximise project risk/upside-potential giving a more realistic estimate of the projectÆs market value - this is shown in practical and simple examples occurring at different stages of a mine project, such as exploration and operation. Final conclusions are provided at the end.CITATION:Martinez, L and Watson, S, 2012. Uncertainty - An important source of (additional) value for mine projects, in Proceedings Project Evaluation 2012 , pp 131-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By J Nell, J Petersen, X C. Goso

The feasibility of increasing the deportment of titanium species and the stability of the pseudobrookite solid solution (M3O5) in a titaniferous slag was investigated, to facilitate the valourisation of titaniferous slags. Thermochemical simulations using FactSage™ software, ver 8.3 (by Thermofact/CRTC and GTT-Technologies), and equilibration-quench experiments were conducted using an appropriate synthetic titaniferous slag composition in an oxygen partial pressure (pO2) ranging from air to 10-16 atm under non-isothermal conditions. The temperature-pressure phase stability diagram for the synthetic slag containing 37.19 per cent TiO2, 19.69 per cent SiO2, 13.12 per cent Al2O3, 16.00 per cent CaO and 14.00 per cent MgO showed that the spinel solid solution (M3O4) was the primary phase until a pO2 of 10-10.5 atm, thereafter M3O5 was the primary phase until a pO2 10-13.2 atm. M3O4 again was the primary phase between a pO2 10-13.2 and 10-16 atm. The changeover of the primary phase coincided with an increase in the liquidus surface. When cooling the slag in a pO2 of 10-16 atm, M3O5 crystallised as a ternary phase that showed a rapid increase in mass while that of the primary M3O4 phase decreased and that of the secondary perovskite (CaTiO3) phase increased at a slower rate. At 1300°C under sub-liquidus conditions, the contents of M3O5, M3O4 and CaTiO3 were about 20 per cent, 15 per cent, and 11 per cent, respectively. Experimental results showed that the Ti3+/Ti4+ mass ratio in the M3O5 phase, ie a measure of the reduction of titanium species, is not considerably sensitive to equilibration temperature in the reviewed range. Slow cooling and minimum/no oxidation during cooling of titaniferous slag would increase the deportment of titanium species to, and the growth and stability of the M3O5 phase.

Jun 19, 2024

By T J. M Harvey

This paper gives an overview of the ASHRAE LibHuAirProp, CoolProp and REFPROP software packages. These packages were predominantly developed for heating, refrigerating and air conditioning engineers and the refrigeration and steam power industries, although CoolProp and REFPROP also cover combustible gases. The main aim of this paper is to highlight the existence capabilities and status of the different packages and where they can be used. The paper gives typical examples of the use of these software packages, specifically as Excel add-ins, and provides a comparison of results of typical mine psychometric and gas drainage calculations using the packages and more traditional ventilation and gas drainage calculation methods. The paper also introduces a hybrid method that improves accuracy compared to traditional methods. In typical mine situations, the use of software packages is probably not required; however, with the increasing accuracy of instruments, potential greenhouse emission costs and the sale of mine gas, more accurate measurements and calculations can potentially save (or make) significant sums of money.CITATION:Harvey, T J M, 2015. The use of psychometric, thermodynamic and transport property software in mine ventilation and gas drainage calculations, in Proceedings The Australian Mine Ventilation Conference, pp 201–210 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015