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After 15 years of operation Australian Mineral Foundation is at the cross-roads: Affected significantly in its last 21 years by Australian dollar devaluation, lower mineral industry activity and severe cut backs in the petroleum industry due to the low oil price, a re-evaluation of its goals and industry support is urgently needed. Industry support, strong at the start, has not kept pace with inflation and expectations of a totally self supporting organisation have proved impossible to sustain. Nevertheless, with a change in emphasis in education programmes, continued creative development of information services and more particularly greater awareness by industry of the services available and hence greater use of the services, industry support is expected to increase. Indeed, industry, it is believed, will accept its responsibility.

Jan 1, 1986

There are two mechanisms in the flo- tation process by which particles are transported from the pulp to the con- centrate: bubble-mineral aggregation and entrainment. It is the chemical processes which occur in the pulp which are critical to the success of flotation since they control the floatability of different min- erals and the selectivity which can be obtained. However, these chemical pro- cesses are so complex that metallurgists are still limited in their ability to predict the floatability of particles in industrial circuits by consideration of the minerals present and the chemical environment. The alternative approach to understand- ing flotation is to examine the behaviour of minerals in industrial flotation pro- cesses, to recognise similarities and differences, and to define the "laws" which appear to apply. Using this ap- proach it has been found that minerals float at a rate which is proportional to their concentration in the pulp, and that the rate of flotation of different min- erals is influenced by variables which' affect the pulp or the froth phase. The ultimate application of this approach is the use of models for circuit simulation purposes. It is this alternative approach which is the theme of this paper. One of the most important problems in understanding the technology of flotation has been in defining the characteristics of the particles being floated. Particles entering flotation vary widely in size and mineral composition, and different par- ticle types float at different rates. These rates do not change uniformly as operating variables change. It has been conventional practice to assess flotation performance in terms of the metal contents of total streams because no better method has been available, and this procedure has obscured important effects which occur in

Jan 1, 1984

Mining is a high risk, high capital and potentially high reward undertaking. A large proportion of the risk comes from a lack of definition of the orebody (which also provides some of the potential) and the unpredictable nature of the market. This makes the planning process difficult but encourages the development of a robust yet flexible mining system. The system should be capable of absorbing some deviation from the anticipated concept without a significant impact on profitability. The mine planning process tends to consist of a series of related but discrete stages. For instance, the pit shells are designed, a schedule for the pit shells is created, a plant fleet is chosen to achieve the schedule and a financial analysis is carried out on that scenario. It is likely a few iterations are carried out using various mill throughputs to produce a favoured financial result. The problem is that handing results from stage æBÆ for use in æCÆ doesnÆt encourage a flexible system. æCÆ is likely to be built for exactly æBÆ. Unfortunately, in mining, æAÆ (the orebody) has the highest potential for variability and impacts everything else downstream. æDÆ the market also has high potential for unplanned variability. These variations can spread and æreverberateÆ through the whole mine process. For example an unexpected increase in ore oversize impacts all downstream mine processes to the primary crusher which may in turn create problems back æupstreamÆ by restricting throughput rate. Also an unexpected drop in demand or price could require modifications to the planned production rates. This paper looks at how mining process simulation can be used to support the development of strategies to counteract unforseen circumstances or alter production to match fluctuations in demand and price.

Jan 1, 2003

By Yeliseyev AK, Shestakov AM

Comminution is the most power-intensive process in the technology for ferrous quartzite concentration. That is why improving comminution efficiency leads to the most appreciable economic effect on the concentration process. The trend towards reducing the lump size of crushed ore before charging the mill is considered to be of major importance in improving comminution efficiency. A considerable number of investigations have been performed in this direction. At the same time, a strong interest is also maintained in the increase of comminution efficiency due to optimisation of process taking place in the mill. Recently, investigations of the power intensity of the breaking process inside the mill have been carried out at the Krivoy Rog Mining Institute. It was ascertained that the routine conditions of comminution at a low mill ball charge ratio resulted in an unnecessarily high power consumption due to the force of impact of falling and milling bodies far exceeding the power required for comminution. For example, the power value for falling balls of 60 - 125 mm in diameter reaches 0.3 kNm, and the force and stress due to ball contact with the lining reaches 60 kN and 250 MPa respectively. These values exceed the force required for comminution by a factor of ten. Analysis of the mechanism of ore particle size reduction during comminution in the ball mill indicates that the size reduction is due to impact load, attrition load, and static load. The efficiency of size reduction is very low. During comminution in the ball mill, impact loads prevail and amount to 85 - 90 per cent of the total load. In this situation, not more than 10 - 15 per cent of destruction is due to attrition.

Jan 1, 1993

By S Arthur, J Mills, A R. Penney

A key aspect of seismic management for narrow vein stoping of the west zone at the Beaconsfield Gold Mine has been the development of a fully remote extraction method that does not require personnel access to sill drives within the orebody once stoping commences. Initially, sill driving within the reef is undertaken in a conventional fashion under geological control. Sill drives are developed at a vertical backs-to-floor height ranging from 7 - 12 m. This mining stage includes all activities prior to the commencement of stoping, after which no personnel enter the unstoped section of the sill drive at any time for any purpose. The key aspect of the remote mining cycle is the use of footwall drill drives paralleling the ore drive at a minimum separation of 6 m under survey control. These drives provide the platform for fan drilling of the orebody. Up to 20 m strike panels are blasted in a single shot using electronic blasting techniques. Ore is mucked from the extraction level sill drive using tele-remote loaders. Aerials for tele-remote operation are installed through boreholes from the footwall drive, negating the need for personnel access to the sill drive. Once mucking of a stoping panel is complete, a laser scanning survey instrument is used to survey the final void for subsequent design and production reconciliation purposes. The survey instrument is mounted in the bucket of the tele-remote loader, and is also operated remotely. Finally, tele-remote loaders are used to dump waste rock fill from the upper sill drive. A system of flags and cameras installed in boreholes from the footwall drive assists the operator in locating the live stope edge during the filling cycle, again negating the need for personnel access.

Jan 1, 2008

Solar Salt, Lunar Ambitions I Bauerti The title of this paper is `Solar Salt, Lunar Ambitions'. It is largely the result of a lack of imagination and a tight deadline. I was seeking a catchy title to convey the image of being 'here' and wanting to get `there', with `there' being a long way away and our being held 'here' by powerful gravitational forces. I tried `Solar Salt, Lunar Landings', but that implied we had already reached `there' when, on reflection, we had not. A colleague suggested 'Solar Salt, Luna Park' which is a fun park in Sydney and, I must admit, there was appeal in the image of having embarked on a wild roller coaster ride with stomach-wrenching twists and turns and the only reward being a pair of sweaty palms, and a feeling of nausea. That's sometimes how it feels when you launch into change. In the end I settled for the more sedate `Lunar Ambitions'. It contained that suggestion of hope and continual striving which are central to the idea of best practice. I will discuss our experiences in this area shortly, but I would firstly like to provide some background to our business. The salt industry is steeped in history and tradition. As one learned commentator observed, common salt is 'a substance seemingly too ordinary to think about, yet it is the oldest of man's raw materials and the basis of some of his newest inventions' (Multhauf, 1978). From ancient times, salt was recognised as a key necessity of life and it has played a role in the rise and fall of governments throughout history. The Romans recognised its importance when they gave their soldiers money regularly to purchase salt, hence our modern word 'salary'. Today, while culinary use remains important, the main consumer of salt is the chemical industry (Figure 1).

Jan 1, 1995

By J Vann, S Dunham, M Job

Two-dimensional (2D) estimation approaches have significant advantages over three-dimensional (3D) approaches when dealing with a narrow vein- or layer-like geometry. The main motivation for 2D estimation is that bias due to non-additivity of grade is avoided. The various aspects of 2D estimation are illustrated by use of a case study from the 1A Shoot Nickel deposit at Leinster, Western Australia. The width of the 1A mineralisation is variable, and so are the angles of drilling intersection. Consequently, the variable of interest (in this case nickel grade) is not suitable for direct kriging because it is defined on non-uniform support. However, grade can also be defined as the ratio of two variables that are suitable for direct kriging: thickness and accumulation. In the 2D approach, tonnage equates to thickness and metal equates to the product of grade and thickness, also called æaccumulationÆ. In the simplest approach we can independently krige accumulation and thickness and derive the grade by the ratio of the two resultant estimates. The thickness and accumulation variables must be in a consistent projection orientation, for example a horizontal projection in the case of steeply inclined mineralisation like 1A. Because the density is not constant across the 1A (and most other) deposits, the issue of density weighting is also discussed. The impact of the correlation between grade and length, or grade and density are important issues in implementation of 2D estimation. The circumstances under which these correlations need to be taken into account (by co-kriging) are reviewed. Finally some comments are made on the final use of the resultant 2D estimate for mine planning purposes.

Jan 1, 2003

By G Diprose

Diamond exploration in Queensland is influenced by the South African approach modified by the discovery of diamonds in Lamproite in Western Australia. The current approach is to explore for Kimberlite and Lamproite bodies using indicator minerals dispersed by fluvial and colluvial processes. In the north-west, diamonds are derived from kimberlitic and lamproitic sources, whereas those in the coastal and subcoastal areas of eastern Queensland are associated with xenoliths included in rocks formed during Cainozoic volcanism. In these areas, sapphire is commonly associated with diamonds. In New South Wales diamonds in economic quantities occur in alkali basaltic intrusions and a subduction model has been proposed for these occurrences (Barrows et al, 1996). Exploration for diamonds in Australia increased following the discovery and exploitation of the Argyle mine. State geological surveys have produced digital information on the local occurrences of diamonds. As part of the Smart Mining Initiative (2006 - 2010), the Geological Survey of Queensland compiled a database and report on microdiamonds and diamond indicator minerals from open file company exploration data from 1968 to 2008 from the Department of Mines and EnergyÆs QDEX system. Most exploration in Queensland was conducted with exploration for other commodities. There is no commercial exploitation of diamonds in Queensland and, to date, only rare occurrences of microdiamonds. There is a regional difference in diamond occurrences with the kimberlitic and lamproitic models favoured for the north-western regions of the State and the subduction (S-type model) favoured for the eastern coastal zone linked to Cainozoic alkalic basaltic volcanism. Further diamond exploration is warranted in Cainozoic basalt provinces along the eastern coastal and near coastal regions and in the north-west of the state in conjunction with airborne geophysics flown as part of current Departmental Smart initiatives. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Mining is a high risk, high capital and potentially high reward undertaking. A large proportion of the risk comes from a lack of definition of the orebody (which also provides some of the potential) and the unpredictable nature of the market. This makes the planning process difficult but encourages the development of a robust yet flexible mining system. The system should be capable of absorbing some deviation from the anticipated concept without a significant impact on profitability. The mine planning process tends to consist of a series of related but discrete stages. For instance, the pit shells are designed, a schedule for the pit shells is created, a plant fleet is chosen to achieve the schedule and a financial analysis is carried out on that scenario. It is likely a few iterations are carried out using various mill throughputs to produce a favoured financial result. The problem is that handing results from stage æBÆ for use in æCÆ doesnÆt encourage a flexible system. æCÆ is likely to be built for exactly æBÆ. Unfortunately, in mining, æAÆ (the orebody) has the highest potential for variability and impacts everything else downstream. æDÆ the market also has high potential for unplanned variability. These variations can spread and æreverberateÆ through the whole mine process. For example an unexpected increase in ore oversize impacts all downstream mine processes to the primary crusher which may in turn create problems back æupstreamÆ by restricting throughput rate. Also an unexpected drop in demand or price could require modifications to the planned production rates. This paper looks at how mining process simulation can be used to support the development of strategies to counteract unforseen circumstances or alter production to match fluctuations in demand and price.

Jan 1, 2003

In Finland fogging in mine ramps is a common problem. Fog forms when warm and humid exhaust air moves upwards the ramp, where the skin temperature of surrounding wallrock decreases to about 10¦C. Changes in fog thickness and lengths of fog-filled parts of the ramp depend at least on climatic conditions outside, diesel equipment usage in the mine, and the length of working sequence at a time. In this study fogging problems in three different mines, namely Orivesi mine, Louhi mine and PyhSsalmi mine, with different ore types, different layouts, and different depths are presented and compared. All these mines use diesel equipment and the ramp is used as an exhaust air route. In two of these mines the ramp is used as a haulage road and in the other for supply and repairing, checking, and surveying purposes. Measurements of humidity, temperature, air velocity, and dust content were performed in these mines. The measurement results, as well as field observations are presented, compared, and discussed. The results show that fog is observed in areas with high relative humidity values when air temperature and dew point temperature are less than 3¦C apart from each other. Air velocity values were high in many areas. In addition, measured particle concentration values were mainly high in areas, where fog was observed. A short literature review of recent fog formation studies is also presented. It demonstrates the complicacy of the fog formation process. Similarities and differences concerning fog problems in the ramps are found and presented. As already a lot of new information is gained, the continuation of research is considered plausible to find more economical ways of solving and preventing this problem in the future.

Jan 1, 2005

By H Waterer, L Zheng, T Kalinowski

The Hunter Valley Coal Chain (HVCC) consists of mining companies, rail operators, rail track owners and terminal operators, together forming the worldÆs largest coal exporting facility. In 2008, the throughput of HVCC was about 92 million tonnes, or more than ten per cent of the worldÆs total trade in coal for that year. The coal export operation generates around $15 billion in annual export income for Australia. As demand has increased significantly in recent years, and is expected to increase further in the future, efficient supply chain management is crucial. The Hunter Valley Coal Chain Coordinator Limited (HVCCC) was founded to enable integrated planning and coordination of the interests of all parties, thus improving the efficiency of the system as a whole. One of the many planning challenges faced by the HVCCC is that of annual maintenance planning. Different supply chain elements, such as trains, railway track, terminal equipment and load points, must undergo regular preventive and corrective maintenance, leading to significant reductions in system capacity (up to 15 per cent). However good alignment of the maintenance tasks can reduce their impact, and the HVCCC undertakes an annual process to ensure the impact of maintenance on the supply chain capacity is as small as possible. This is achieved in an iterative negotiation process between HVCCC and individual service providers. In the past, maintenance schedule optimisation was largely manual, which for the more than 1000 tasks involved is quite labour-intensive.In this paper the authors describe an approach developed at the University of Newcastle in partnership with the HVCCC to automate this schedule optimisation process. We will discuss our experience in applying exact (mixed integer programming) and heuristic techniques from mathematics and computer science to address the problem. This work is anticipated to lead to new decision-support tools for the HVCCCÆs capacity planning team.

Sep 26, 2011

By P Scott

Kaltim Prima Coal, an open cut coal mine located in Sangatta, East Kalimantan, Indonesia, operates two deep pits and two shallow pits with a truck and shovel operation. KPC produced 17 Mt of coal in 2002 by removing 120 Mbcm overburden. Geochemical investigations have indicated 20 per cent of total waste rock is potentially acid forming; ie it has the potential to create acid mine drainage (AMD). In the early years of the KPC operation, the presence of AMD had been observed in the mined out areas and in the waste rock dumps as a result of sulfidic waste rock exposure. A strategy for management of AMD from waste rock was implemented involving: sampling, analysis, modelling, selective handling and validation of final dump covers. Samples of the waste rock lithologies are collected from exploration drill holes for geochemical analysis to determine their acid generating potential. The geochemical database is used to develop the waste rock model for the life of mine pit areas. The acid forming and non-acid forming waste rock is delineated for each mining bench area for selective handling and placement within the waste rock dump during the operational stage. Each mining bench is sampled and assessed to validate the model predictions. The final dump cover is sampled to meet strict Quality Assurance requirements to ensure non-acid forming waste material is used in the outer cover of the dump. The geochemical investigation of the waste rock is integrated with mine planning to design and construct the waste rock dump to minimise the risk of generating acid. This process links the exploration stage, operation stage, and rehabilitation stage for each Pit area. The paper briefly reports the waste rock characterisation, waste modelling and strategies used for management of acid drainage by KPC.

Jan 1, 2003

Vatukoula, the Fijian equivalent of gold rock, is the name of the community embracing the gold mines owned and operated by Emperor Gold Mining Company Ltd., Loloma (Fiji) Gold Mines, N.L., and' Dolphin Mines Ltd. It is situated in the Tavua Goldfields approximately five miles from the northern coast of Viti Levu, the largest island of the Colony of Fiji.The climate is sub-tropical, there being a definite wet and dry season. The wet season is somewhat variable in length but usually extends from December to March, during which time most of the rainfall for the year is recorded.Although the average annual rainfall is 71 in., more than twice this amount has been recorded. Precipitation at the rate of 5 in. per hour is not uncommon and 15 in. of rain has been registered in 24 hours. The mining methods adopted, therefore, had to suit these wet conditions.The occurrence of gold in the Tavua area has been known since 1872, but it was not until 1932 that discoveries were made which led to the formation of the present operating companies. In 1934 the Emperor Gold Mining Company Ltd. commenced operations, followed in 1935 by the Loloma (Fiji) Gold Mines, N.L., and later by the Fiji Mines Development Ltd., now known as the Dolphin Mines Ltd. Up to the end of 1951 these three mines had produced 2,501,688 tons of ore from which 1,277,881 oz. of fine gold and 347,429oz. of silver were obtained, realizing in Fijian currency £13,025,153.The three mines are situated close togeth.er on contiguous mining leases, and, although under common management, are operated as separate en,tities. Since 1944 all the...

Jan 1, 1953

Launching the Queensland Water Plan 2005 - 2010 in August 2005, Premier Peter Beattie compared the stateÆs water resources with liquid gold. QueenslandÆs peak industry body for the minerals and energy sector, the Queensland Resources Council (QRC), believes the analogy is appropriate. During early development of an industry water strategy, it has become apparent that water is like liquid gold, in that it is revered, hoarded, recycled, priced on purity, a magnet for speculators, both difficult and expensive to transport effectively, heavily regulated and fundamentally linked to issues of security. To date it has generally been economic and relatively straightforward for the resources sector to secure water. Although production has not been compromised, this must not be grounds for complacency as there is every indication that water will continue to become increasingly expensive, more tightly regulated and, relative to a growing demand for a finite water supply, increasingly scarce. During 2006, QRC has developed and is implementing a voluntary industry water strategy to address a range of challenges confronting the resource sectorÆs security of access to water. As a consequence of, at times, protracted community consultations over QueenslandÆs catchment-based water planning processes it has become clear that many community stakeholders have outdated perceptions of the stateÆs resources sector. Once established, QRCÆs water strategy will incorporate a community engagement campaign to present the industryÆs credentials as a leader in water resource management. The development of QRCÆs water strategy, and the challenges the strategy is designed to address, provides insight into the fundamental reforms that are occurring in how water is managed and regulated in Queensland. These reforms have implications for how government policies are designed and administered and also for how industry engages with communities during this transition process.

Jan 1, 2006

The paper describes the preparation of new rail guides, removing existing rails, and replacing with new rails in a vertical winding shaft.INTRODUCTIONThe general practice in coal winding shafts is the use of two cages, with one or more decks in which men and materials are raised or lowered. Winding speeds vary according to depth, the type of winding gear, and whether winding is done in downcast or upcast shafts. Each cage occupies a position between the centre and side of the shaft, with a clearance depending on the type of guides used. The function of the guides is to keep the cage in position throughout the entire depth of the shaft. There are three types of guides, two of which are in general use.1. Selected wood of about 6 in. square section, fixed to the side of buntons.2. Solid strand steel made up similarly to that of an ordinary wire rope, suspended from the head frame with weights attached to the lower end.3. Standard T-rail sections fixed to end or side buntons. Of the three types, 2 and 3 are in general use. The type used in the particular case, the subject of this paper, is T-rails of the standard section used in railway work.GENERAL DESCRIPTION OF SHAFTDetails of the shaft are as follow: Diameter of shaft: 22 ft. inside lining.Depth of shaft: 900 ft., including sump.Concrete lined throughout.VENTILATIONThe ventilation shaft is used for the upcast, through which all vitiated air passes to the main ventilation fan. Quantity of air passing up the shaft is 400,000 cu. ft. per minute. The air is highly saturated during the summer weather and slightly less...

Jan 1, 1947

By E Ahern

In exchange for issuing minerals rights from the Crown Mineral Estate to explorers and miners, the Crown expects a æfair returnÆ on this investment, ultimately for the benefit of all New Zealanders. In the case of mining permits, this return is in the form of a tangible asset û royalties from mining activities. But for exploration activity, the return sought by the Crown is an intangible asset û information. The information obtained serves three purposes û in helping Crown Minerals to set work programme conditions during permit allocation, for monitoring the performance of permit holders in accordance with permit conditions, and for archiving and making available for future interested explorers and other parties. Difficulties can arise during the allocation and monitoring process when either party has more information than the other that is not shared. To date not enough emphasis has been placed on the intrinsic value and content of the information generated by explorers and the importance this information can have in the exploration process leading to new mineral discoveries. For attracting exploration investment, the quality and availability of such information, combined with other geoscientific data, is a fundamental determinant for potential explorers when choosing to explore in a global market, and strongly defines the mineral prospectivity for a country. This is something the Australian States and other jurisdictions seeking mineral investment learnt long ago, and who now provide substantial amounts of cheaply or freely available packaged geoscientific datasets, increasingly over the Internet. To have a vibrant mineral exploration industry so that the benefits from the mineral estate can be realised for all New Zealanders, a shift in emphasis to the value of its mineral information base itself is required. Such an approach is befitting of a true Knowledge Economy, and would enable the Crown to make better-informed decisions regarding utilisation of its natural resources.

Jan 1, 2002

By M Fimeri, R Williamson

Sample sizing in the iron ore industry requires significant manual effort to collect, transport, and sieve the samples as well as record, process and report the data. Efforts have been made to automate this process, which essentially emulate the manual process, except that a person is replaced by a robot. Even in these cells, the sieving and sizing operation consumes a significant proportion of robot time. The proposed doubling of production from AustraliaÆs iron ore mines over the next five years will place increasing pressure on sample sizing and interest is increasing in alternative automated methods. One such method is the adaptation of computer vision technology which has been successfully introduced into the mining industry in a range of applications including feed size distribution to SAG mills and oversize detection from screening stations. The limitation of this technology is that only the top surface is visible and this is used as an indicator of total size distribution. Obviously in a sample plant, where 100 per cent of the sample must be measured for acceptable quality assurance, this approach is unacceptable. In order to capture 100 per cent of the sample using computer vision technology a monolayer must be formed either by spreading the sample across a moving surface, such as a conveyor or vibrating platform, and passing this under a camera. This will become a æsurgingÆ load which presents specific problems for some types of computer vision systems, namely those relying on a 2D approach. In this paper a 3D computer vision technology will be described which overcomes the problems associated with measuring particle size in a monolayer and experimental results will be presented which demonstrate its effectiveness for lump and fine iron ore sample size measurement.

Jan 1, 2008

An understanding of the way that solutes are transported in mining or natural environments is essential to the development of sound strategies for managing waste disposal. Research on miscible pollutant movement in unsaturated porous media is carried out both experimentally and numerically. Results of numerical modelling are obtained by solving the groundwater flow equation and the solute transport equation. The finite element method is employed and comparisons between simulation results and experimental data are found in remarkable agreement.

Jan 1, 1995

By Kister H

Hoesch HUttenwerke AG, Dortmund, West Germany, is an integrated steel work of the Estel-group. The nominal annual production capacity-is about 7 Mio tons of steel. Hoesch has along experience in operation of diffe-rent types of slag granulation plants and of utilization of the granulated product. This experience is used to granulate a large amount of blast furnace slag and to process it in own cement plants and produce blast fur-nace cement.

Jan 1, 1979

The state-owned Swedish company LKAB is one of the world's largest producers of iron ore. LKAB mines the greater part of its ore underground, and very high efficiency is vital if it is to compete successfully with open pit mines. Consequently, computers and OR are essential parts of the company's operations. This paper gives some examples of success- ful computer and OR applications at LKAB, coupled with some remarks on the costs and benefits of OR.

Jan 1, 1977