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The 3.5 million tones per annum Enterprise mine is the newest underground copper mine at Mount Isa in northern Australia. At a depth of up to 2000 metres, it is the hottest and deepest mine in Australia. In situ rock temperatures sometimes exceed 60¦C requiring the installation of substantial amount of refrigeration to provide safe working conditions for mine workers. The latest refrigeration project at the mine, R67, required the design and installation of the worldÆs largest bulk air cooler and AustraliaÆs largest chilled water plant. The plant is mounted on the surface of the mine and provides 25 MW of refrigeration to cool some 580 kg/sec of ambient air to 11.4¦C. This is equivalent to the production of 6300 tonnes of ice per day. The plant was designed for high availability, as any downtime would result in substantial production losses to MIM, and also had the potential to quickly result in unsafe levels of heat stress within the underground workplaces. The bulk air cooler has been designed for a capacity of 34 MW(R), the expected ultimate carrying capacity of the 7 m vertical intake shaft. Being located well inside the tropics, technical issues such as control of thermal pulldown required special consideration. Also, the bulk air cooler had to be designed to handle whatever demand for fresh air was imposed by the mine below, with over 100 per cent variations in airflow expected, and without loss of thermal efficiency. A substantial program of risk assessment and HAZOP studies was used to protect underground miners from leaks of ammonia into the air or water circuits. Fully automatic control systems result in a totally unmanned plant that is supervised remotely. To improve efficiency, the plant is controlled by the outlet air temperature from the bulk air cooler û the first in the world to be controlled in this fashion. Engineering solutions to address environmental considerations were incorporated at the design stage through features such as the use of ammonia (a greenhouse-friendly gas) as the refrigerant, zero atmospheric discharge and a wastewater collection and re-use system.

Jan 1, 2002

By Kelsall D. F, Trahar W. J

The size by size batch flotation behaviour of copper activated sphalerite from synthetic mixtures with quartz was determined. In terms of recovery of sphalerite, the size fractions could be grouped into coarse, intermediate, and fine ranges. The behaviour of the coarse and fine ranges was significantly poorer than that of the intermediate range in both the extent and rate of flotation.Each size fraction had a fast and a slow floating component.The main effect of changing the copper sulphate addition was to alter the proportion of any size fraction which was fast floating. No correlation could be found, between the amount of copper on the spha:lerite andeither the flotation rate of the mineral or the amount of copper added to the system. It was found that fine particles did not appear to consume greatly disproportionate amounts of copper sulphate during conditioning. A modified conditioning procedure was found to lead to a higher rate of flotation and recovery of coarse sphalerite and to make poss1ble substantial savings of copper sulphate.

Jan 1, 1975

The dissolution of gold in cyanide has been studied, using both chemical and electrochemical techniques. The electro-chemical studies have confirmed that gold may become passive in cyanide solution if its potential becomes more positive than -O· 5 V v. saturated calomel electrode (S.C.E.). The results of the conventional solution rate tests suggest that, although the solution rate is controlled by the rate of diffusion of oxygen at low oxygen and agitation levels, when these are increased the gold may become passive and its solution rate approach a steady value, or even decrease with increasing oxygen level. The passivity of gold has been shown to be of importance in the solution of small spheres of this metal, and in the extraction of gold from a calcined auriferous pyrite concentrate.INTRODUCTIONAlthough it has been appreciated for many years (McLaurin, 1893, 1895) that dissolved oxygen is a necessary adjunct to the solution of gold by the cyanide process, attempts to quantitatively assess its effect have led to conflicting results. For example, Barsky, Swainson, and Hedley (1934) reported that an increase in oxygen concentration improved the solution rate, but Beyers (1936) claimed that such an increase would reduce the rate at which the gold dissolved.By using an electrochemical approach Kudryk and Kellogg (1954) showed that the diffusion rate of either the cyanide or the oxygen was a controlling factor, and that, if the mole ratio of cyanide to oxygen concentration was greater than 10, the solution rate was proportional to oxygen concentration.These results, although they represent some of the most careful work available, were in direct contradiction to the findings of Mills (1951), who found that gold may become passive in cyanide solution, with a resultant decrease in solution rate.

Jan 1, 1963

By J Harding, S Munro, R A. Bearman

Despite the importance of the primary crushing stage, performance optimisation is not well analysed with sufficient focus to give improvement opportunities. At the Newcrest owned Telfer operation, liner life plays an important part in scheduling planned maintenance. Major consideration is given to monitoring crusher performance, as the highly abrasive nature of the feed significantly impacts the liner wear life. A study was undertaken by the lead author which focused on establishing a strong baseline of accurate data pertaining to the performance of the crusher, in terms of, operating parameters, liner life and key machine design factors. As part of the study, mining feed materials were examined for a particular set of liners and this revealed that improved methods should be pursued. Due to the competitive nature of the mining industry, the business solution to complex problems with long shutdown cycles should be streamlined to incorporate a non-operational modelling approach that is significantly more efficient than traditional online trial and error methods. In order to dramatically reduce the time and business risks, it was decided to engage services to model and simulate the liner life by varying main operational and mechanical factors. The key to all simulation work is gathering high quality baseline data. Such data allowed deployment of the Kinematic Crusher Model and validation of the model against worn 2D wear liner profiles. The proven model was then successfully deployed to predict operational values that defined crusher performance. To enhance the study, further investigation into a set of mechanical and operational simulations generated a sensitivity matrix measuring key performance parameters throughout the wear life of the liners. The study revealed throughput as a highly sensitive parameter and a change in eccentric throw provided the greatest improvement in extending liner wear life.

Aug 24, 2022

By McLennan R. G

The principle of personal safety is as old as the human race. The application of this principle to industry is of much more recent origin, and may be said to be almost exclusively the product of the twentieth century. The enormous strides in technique and production mode prior to the turn of the century had been achieved without any real regard for the crippled human by-products of that expansive era. It was accepted that. accidents were inevitable and formed part of the price that must be paid for production. It was not until 1885 that the first Workmen's Compensation Act was passed in Germany making the employer financially liable for injuries suffered on his plant.With awakening social conscience came the first organised efforts to reduce accidents in industry. Early 19th century literature dealing with the development of powerdriven machinery and the growth of industry in Europe contains many references to the unsafe and unhealthy working conditions that accompanied the change-over from the home workshop to the industrial plant. By the year 1900, there were in Germany - and a little later in England governmental regulations dealing with the guarding of hazardous machinery. American industry, now the acknowledged leader in industrial safety, admits freely that when an organised safety movement commenced in that country, there was already a considerable amount of information available to them from European experience. The steel industry was well to the fore in this work, and in...

Jan 1, 1957

ABSTRACTMechanised cut and fill stoping in the Racecourse orebodies between II and 9 levels was started in 1964.Five stopes are in progress over the two level interval, extracting the full strike length (600-2,000 ft) of each orebody without transverse pillars.Each stope is served by a central 10 ft by 12 ft service intake ventilation raise and an 8 ft by 8 ft return air raise at each end of the stope. Each stope is divided into two sections for drilling. firing. mucking, and fillingto maintain steady production. All equipment is kept in the stope for one level lift stoping. Gardner-Denver 2 boom jumbos are used for uphole drilling and Wagner ST 5 Scooptrams for loading and transport to ore passes located in the footwall of the orebody. A Wagner PTIO is used for materials handling and scaling of the stope backs.Mill tailings, after one stage of cycloning are used to fill the stope, one section at a time. About 80 per cent of the water is removed by decantation while the remainder percolates through hessian-covered pipes and boxes.The ore is passed to 11 level where it is hauled by the 3 ft 6 in. gauge train to the tipple at the shaft area. The ore is crushed underground before hoisting to the surface.A performance of about 100 ton/manshift is achieved by the drilling, blasting, and mucking crews in the stopes.

Jan 1, 1968

Improving Pelletisation of Pyrite Cinder by High Pressure Roller Grinding As an important secondary resource for ironmaking, pyrite cinder is characterised by coarse particle size, low specific surface area, high porosity and poor surface activity, which leads to high bentonite dosage, low strength and too high moisture of green balls and high roasting temperature. In this paper, a study of improving the pelletisation of pyrite cinder containing feed by using high pressure roll grinding (HPRG) was presented, which aimed to improve the quality of green pellets and reinforce roasting performance pellets. It is shown that pyrite cinder is characterised by complicated mineral compositions dominated by haematite and metal sulfides, porous surface and middle class ballability, leading to higher balling moisture, higher bentonite dosage and higher firing temperature for pellet hardening. The pelletisation of pyrite cinder can be improved by high pressure roller grinding and blending with magnetite in the pellet feed. The former is probably ascribed to the increase in specific surface areas of pellet feed from 850 cm2+g to 1690 cm2+g when the pellet feed passes through roller twice. Good quality green balls and fired pellets can be made from feed comprising 40 - 60 per cent pyrite cinder and 60 - 40 per cent magnetite concentrate at small scale under the following conditions: 1.2 per cent bentonite, feed passing through roller twice at 7 per cent moisture at 1.5 ton pressure, balling at 13 per cent moisture for 13 min, preheating at 1050¦C for 12 min and firing at 1300¦C for 8 min. Green balls possess such properties as drop numbers of 6.5 times, compressive strength of 19.1 Newton and thermal shock temperature of 533¦C. Fired pellets are imparted high compressive strength of over 3000 Newton per pellet. Small scale tests have been proven by pilot scale tests that high grade fired pellets are made, assaying 63 per cent Fe and minor other impurities, such as sulfur and phosphorus except for copper content. The fired pellets made of three blends possess excellent metallurgical performance, such as reducibility index higher than 65 per cent, reduction swelling index lower than 15 per cent and low temperature reduction degradation lower than2 per cent. Especially the compressive strength after reduction is higher 719Newton per pellet.

Sep 13, 2010

Significance of Ion Interactions in Flotation in Saline and Brine Solutions

Sep 13, 2010

By J Jackson, E Sellers

Blasting related indices were developed to quantify variation in rock strength and structure for each stope, and for each lift of each stope, as part of a Mine to Mill study at an underground open stope mine. The indices were derived from combinations of data from underground diamond drilling because the simplifying assumptions contained in the block model prevented sufficient differentiation in rock mass characteristics to enable adjustments to the blast design.Application of combinations of blasting related indices enabled the identification of stopes with a high potential for inconsistent and oversize fragmentation, underbreak and overbreak. The indices also fragmentation outcomes to deliver increased material flow within stopes, better digability and predict indicative mill throughput. The stopes with issuesCalibration of the results enabled adjustments to the blast design based on the rock mass conditions and accordingly improved the blast outcomes. This enabled improved productivity by reducing underbreak and overbreak, having a more appropriate fragmentation, which reduces unplanned rock handling and improves bogging. The reduction in recovery drilling creates huge opportunities to improve output by reducing production delays and decreasing the overall cost per tonne. By understanding the explosive performance and blast energy distribution in relation to rock mass blastability poor, performing designs in blind upholes and convex stopes were identified.The conclusion of the work is that value improvement, regarding increased revenue and reduced costs, can be achieved across the whole underground Mine to Mill process chain by developing stope based indices from the existing geological information to correctly tailor the blast design to the rock within, and surrounding, the stope.CITATION:Jackson, J and Sellers, E, 2017. Blasting related indices as the key to underground blasting improvements in a challenging rock mass, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 23–32 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

Factual data about the sedimentation in the Newcastle Coal Measures are presented. Data concerning the total coal measure sequence (isopachs, sand/shale ratio, and total coal thickness variation), data about three coal seams (Borehole, Dudley, and Victoria Tunnel) and data about interseam conglomerate units are discussed.From this data conclusions are drawn about the coal measure environment. The western edge of the coal basin, the Lochinvar Dome, although a high feature, was apparently stable during coal measure time. Despite its height it apparently supplied little sediment to the basin.The northern and north-eastern edge, which was unstable, supplied most of the coarse detritus (including the conglomerates) to the basin. The conglomerates show patterns of fluvial origin but after a period of "normal" variations in pattern they become restricted to two parallel zones evidently tectonically controlled. Deposition of conglomerates is episodic and separated by periods of coal formation when deformation was apparently slight. Formation of each of the three seams considered followed a rather similar pattern- each show development of thick coal around the basin edge and poor thin coal in the "axial" region of the present synclinal structure.Evidence of ill situ formation of some areas of the seams is discussed and periodic deformation of the basin during coal measure time is postulated.The unusual character of this coal basin, in particular the very coarse units, is stressed, despite the presence of many "normal "coal basin features.

Jan 1, 1970

In 1976 the Pitjantjatjara Council was established under the Associations Incorporation Act 1985 (SA), for the initial purpose of organising and bringing together three similar Indigenous groups. These members of the Pitjantjatjara Council of Central Australia were demanding land rights and to legally protect their traditional lands. The Land Rights movement was more focused on the South Australian Government that became more receptive to the general notion that Aboriginal freehold land could be attainable.For almost five years, Pitjantjatjara CouncilÆs intense negotiations took place with the Dunstan and Tonkin Governments culminating in the final passage of legislation by 1981. A bi-partisan approach by Government and opposition applauded by all South Australians for its mature and socially responsible actions, in line with the Aboriginal Land Rights (Northern Territory) Act 1976 (Cth). Despite the similarities between South Australian and the Northern Territory Land Rights legislation, there still remains one obvious distinction. In the Northern Territory case, its legislation established æLand CouncilsÆ as statutory authorities that are responsible for the management and use of designated Aboriginal lands. On the other hand, South Australian legislation fails to include any reference to æLand CouncilsÆ as defined in the Northern Territory Act. The intention of establishing such æLand CouncilsÆ in the Northern Territory was, and is to provide legal, anthropological and other expect advisers that respond to the wishes and opinions of Traditional Aboriginal Owners. Negotiations between mining companies and Land Councils, will, after the granting of mining leases, monies are then transferred to those Councils being a percentage of royalty entitlements. While the Pitjantjatjara Land Rights Act 1981 (SA) (Act) does provide royalty arrangements to Anangu Pitjantjatjara (AP), a body corporate pursuant to the Act as a Landholding Body (and not as a æLand CouncilÆ), it does not provide any royalty payments for the legal and anthropological services by the Pitjantjatjara Council for providing essentially similar services as the Northern Territory Land Councils. The limited services by AP do provide complimentary services from other organisations û including the Pitjantjatjara Council. There are approximately 4000 Anangu members who reside on AP Lands and more than 1000 other Anangu members live near AP Lands in Western Australia and the Northern Territory. These people are defined as APÆs æTraditional OwnersÆ by virtue of their affiliation to portions of AP Lands. As a result, the depth and understanding of spiritual beliefs and customs are strongly present as it relates to the whole of the Lands. Most of these members reside at permanent communities that spread unevenly about the northern and south-western parts of AP Lands. In addition, there are numerous æHomelandsÆ where families and extended families have establish homes, with electricity and water supplies on those Traditional Lands (see Appendix 1 and 2 of this paper depicting the map showing AP Lands and also showing stunning photographs taken during late last year). All roads and airstrips are unsealed between communities and Homelands and the essential services to all communities are limited and costly to provide, and require continuous upgrading. Capital expenditure on infrastructure is sorely needed and alarming levels of unemployment is of serious concern. Tjilpi (older) Anangu members have continually discuss the urgency to provide employment and education for the future of their children and grandchildren while balancing the needs of maintaining cultural and spiritual considerations. It is thus a growing realisation by many Traditional Owners that long-term benefits occur as a result of exploration and production of oil or minerals. There are promising results from Primary Industry and Resources of South AustraliaÆs (PIRSA) Aero-magnetic Surveys on the Musgrave and Mann Ranges and soon to be completed surveys of the remaining southern half of AP Lands (see Appendix 3). PIRSA and mining companies û such as Rio Tinto Exploration Pty Ltd and Delta Gold NL û have been more conscious of the necessity for improving the dissemination of information to Traditional Owners and to AP members. With recent findings of large nickel deposits just over the border in Western Australia, there is a strong indication that discoveries may occur on AP Lands as similar geological information is present on the east Musgrave Block. Consequently there are concerted efforts by the legal and anthropological services of the Pitjantjatjara Council to arrange Workshops and Summit meeting to give extra information û particularly information concerning the true effect of large-scale mining operations û to members to properly consider these proposals. Pitjantjatjara Council will play a major role in any decisions effecting Traditional Owners and AP, and will ensure orderly and professional services when dealing with legal, cultural and sensitive matters. This paper addresses the historical and current relationship between Pitjantjatjara Council and AP, with an emphasis on mining operations on AP Lands. It argues that future economic and social development on AP Lands hinge predominantly on the legal recognition of the Pitjantjatjara Council for its ongoing role, responsibilities and protection afforded to AP and its Traditional Owners.

Jan 1, 2002

This technical note describes a problem with WANG82, a ventilation network analysis programme. The problem was highlighted by Renison Ltd when using the programme on large, complex networks. Under certain circumstances the programme produced incorrect results or failed to converge to a solution.

Jan 1, 1986

By R B. Stewart

Where pasture production is the intended land use of the areas to be reclaimed, the creation of a suitable growing +medium is a major objective. To achieve this land reclaimers require a sound understanding of the proposed mining plan and a knowledge of the physical, biological and chemical properties of materials intended for resurfacing disturbed areas. Where the original soil is not being replaced in its natural state, research is usually required to determine an alternative growing medium. Results from field research conducted on waste material from the Waihi Gold mine are reported with emphasis on the significance of soil depth in relation to pasture production in this environment.  Problems in extrapolating field research to large scale operations are also considered.   Essentially the requirements for successful pasture production, on surrogate growing medium, are akin to conventional approaches used in New Zealand in the development of unimproved agricultural land. High inputs of fertiliser are initially needed, especially where volcanic soil is used, and careful management of pastures and soils is required to minimise soil erosion and create a sustainable system. In the first three to five years of pasture production, grazing use of the land requires to be dictated by pasture availability and soil conditions and not by animal feed requirements. The use of light stock (young dairy or sheep) is recommended.   Successful land restoration requires a team approach by a range of cooperative specialists including engineers, soil scientists, farm managers, agricultural contractors, landscape architects and environmental officers.

Jan 1, 1991

An account is given of experimental apparatus for generating a short duration high velocity water jet and the effect of its impingement on various rock samples under air or water cover. The penetration was found to be highly dependent upon the rock structure; in general material with closely interlocking grains was resistant.The damage sustained by a stationary sample held close to the jet did not vary greatly whether the sample was in air or confined under a water layer; but when the sample was translated under the jet there was a marked increase in the damage sustained.Some consideration was given to the possible practical application of a water jet for deep hole drilling and an estimate made of the power requirements and transmission losses for such a system.

Jan 1, 1969

ABSTRACTOperations Research and associated techniques have wide application in the Mining Industry and have been used in Mount Isa since 1961.Typical of the projects undertaken by the OperatIons Research staff are1. the development of a complex computer programme for use in economic evaluation of mineral deposits,2. development of a production scheduling and control system for a complex mining operation,3. SImulatIon of a metallurgical plant operation to test the adequacy of design specifications and4. analysis of vehicular accident data to valuate alternative courses of insurance action.

Jan 1, 1968

By P W. Wypych, D Curry, A P. Grima

The market has become highly competitive for engineering and equipment vendors, who are challenged to reduce costs while improving efficiency and productivity of mine operations through plant improvements and expansions. Although conveyor transfer systems account for a small percentage of the infrastructure cost of a mine, they form an integral part of the process supply chain. Malfunctions or suboptimal performance can result in substantial financial cost from delayed start-up, unscheduled downtime, reduced throughput and increased maintenance costs.Discrete element modelling (DEM) is a powerful simulation method used to virtually prototype and test the performance of transfer equipment throughout a design cycle. When developed and applied correctly, DEM can provide insight into performance that exceeds the traditional analytical methods, especially when dealing with complex ore properties, behaviour and/or situations.Using case studies sourced from the authors’ recent research and industrial project work, this paper will address the industry goal to increase efficiency and productivity as well as the methods available to the engineers responsible for delivering designs that meet the aims of this strategic approach.The main focus of the paper will be the new calibration technology, which has been developed by the authors to generate DEM material models that are linked to real-world properties and flow behaviours via unique dynamic testing and innovative parameter calibration methods. These calibrated DEM material models can be deployed by engineers into their existing workflows, whether it be for feasibility studies, concept or final design, plant troubleshooting or optimisation.This new technology allows engineers to gain greater insight than that provided by traditional approaches to the design of transfer chutes and other process equipment and also allows informed design decisions to be made that meet industry efficiency and productivity requirements.CITATION:Grima, A P, Curry, D and Wypych, P W, 2015. New discrete element modelling calibration technology to facilitate the increased efficiency of ore handling and processing operations, in Proceedings Iron Ore 2015, pp 449–464 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Most mining operations have been happy to live in blissful ignorance of what their equipment is really capable of. Shareholders have been shown increasing tonnes output per employee (due to rationalising employee numbers). It is now known that the best practice for large mining trucks is 52 per cent higher than average or best practice for excavators is 41 per cent higher than average, or 38 per cent in shovels or 35 per cent with draglines, etc. The data is available. The bell curve of performance is flat. Substantial underperformance is rife. If you are working in or supplying equipment or services to one of the majority of operating mines that donÆt achieve best practice surely you want to know why. Or maybe you donÆt? For many mining people this sort of knowledge could be dangerous to their career so keeping the MD or CEO in the dark is a good option. Many suppliers donÆt want the performance of their equipment benchmarked? Mining consultants donÆt have the data so they are happy to keep guessing. Unfortunately, many Business Improvement or Business Excellence projects are about ticking the participantÆs æcareer boxesÆ. The first step to capacity utilisation is knowing what the capacity is. Even then people and culture will get in the way. People are the biggest hurdle to capacity utilisation. This paper will discuss what the mine of the future (and today) will need to do to utilise the productive capacity of its assets. It is not just benchmarking. It is not just automation. It is not just technology. It is about engaging those people who impact on equipment performance; right from the operator up to the Mine Manager. Doing it better involves a process to facilitate change and a culture which says it is OK to try even if you are wrong.

Jan 1, 2009

By R Soong

The Wharekirauponga (WKP) epithermal gold-silver deposit is located about 10 km north of Waihi in the Hauraki Goldfield east of Auckland. WKP is notable for its sheeted to stockwork quartz veins hosted in rhyolitic rocks, that have attracted exploration interest as a low grade, bulk tonnage exploration target. Exploration between 1978 and 1993 included 23 diamond drill holes totalling 5505 m. The mineralisation occurs in a rhyolite dome complex (Miocene), consisting of flow-banded rhyolite and rhyolitic pyroclastic rocks, with minor andesite. Fifty four drill core samples were collected from six exploration drill holes and analysed by semiquantitative XRD techniques. Hydrothermal alteration of the rhyolitic and andesitic rocks has developed secondary mineral assemblages of quartz, adularia, albite, chlorite, illite, sericite, interlayered illite-smectite, carbonate, halloysite and pyrite. The main zone of mineralisation is characterised by quartzadularia alteration, which grades oiItward to quartz-clay (illite, local halloysite and/or interlayered illite-smectite) alteration. Propylitic alteration is present at the southern end of the drilled area of the prospect. Depth-related changes in mineralogy include a decrease in illite and appearance and increase in quantity of chlorite with increasing depth, and the localisation of halloysite and interlayered illite-smectite in the shallow parts of some drill holes.

Jan 1, 2001

This paper summarises the development t,) date for the Hidden Valley Gold (HVG) Project. It starts with the original exploration work, covers the detailed feasibility study activities and concludes with the current phase of extra exploration drilling. A brief technical summary has been made from the various mining, process and environmental studies that were undertaken as part of the project approval process. A discussion of the influential non-technical factors is included, as well as a view of the future prospects for an operating mine. The project was always seen as marginal, given the low grades, small resource and short mine life. However the capital and operating costs were lowered with aggressive design and it was regarded an acceptable development by CRA. The opportunity was taken to review the project when delays in start-up were encountered. An updated financial evaluation showed a subeconomic resource in 1990 terms and this resulted in a new exploration phase to identify a larger deposit.

Jan 1, 1991

By R B. Turner

The authors have studied and analysed many mineral resource and related projects in Australia. These studies have lead them to conclude that the past performance of many project developers does play a major part in any external financial investment for new or expanding resource based projects. In this paper the authors look particularly at the influence of parties outside the direct control of developers and the effect of' these parties on projects and conclude with a number of points as guidelines for potential project developers.

Jan 1, 1980