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By E Baafi, G Brassington

Coal mining operations can impact on various types of surface infrastructure or natural features, including cliff-lines, steep slopes and natural watercourses. Longwall mining leads to a subsidence depression due to the changing geometry of the mined out area. The current regulatory process for managing subsidence in New South Wales (NSW) involves the preparation of a Subsidence Management Plan (SMP). This paper demonstrates the use of a Weights of Evidence (WofE) technique applied within a Geographical Information Systems (GIS) environment to predict potential areas for rockfalls along cliff-lines in the NSW Southern Coalfield. The WofE is a ædata-drivenÆ method that can be used to predict subsidence impacts prior to mining. The WofE method was applied to ten known rockfalls along the Cataract River to evaluate the reduced impact of not mining within 50 m of cliff-lines along the Nepean River. There is significant reduction of probabilities of rockfall occurrence when mining is avoided within 50 m of cliffs.

Jan 1, 2006

By Yavuz Ali Topkaya

Rare earth ferrosilicide is a versatile alloy mainly used to control the detrimental effects of sulfur in steel and to modify graphite structures in cast iron. The aim of this study was to determine the optimum conditions to make rare earth ferrosilicon alloy using a preconcentrate produced from a bastnasite type of ore present in the Beylikahir-Eskisehir region of Turkey. This concentrate contained 23.5%REO, 41.37% CaF2, 10.69% BaSO4, 8.50% CaCO3, 4.18%Fe2O3, 2.83% Al2O3, 2.74% SiO2, 1.20% P2O5 and small amount of other oxides. The initial metallothermic reduction of this concentrate using ferrosilicon and aluminum in a graphite crucible placed in a muffle furnace gave very low recoveries due to the difficulties encountered in adjusting the slag composition, temperature and amount of additives. Therefore, two batches of rare earth oxide concentrate containing 61.1% and 81.7% cerium oxide, respectively, that were procured from a Turkish glass producer, were used to optimize with respect to temperature, duration, slag-making additives and amount of reducers. In these experiments, smelting and reduction was done in an induction furnace with graphite crucible, and, ferrosilicon and aluminum were added after melting the charge. As a result, there was no difficulty in obtaining a rare earth ferrosilicon alloy containing 35-55% RE, 5-25% Fe and 20-40% Si, with about 80% metal recovery. When the optimum conditions were applied to the preconcentrate, alloys of similar compositions were obtained with 70-80% recovery. Experiments were also done with mixtures of preconcentrate and rich concentrate, and, recoveries as high as 95% were obtained. Only in this case, to increase the recovery, mixtures had to be charged to the empty graphite crucible after heating the crucible to the required temperature.

Jan 1, 2006

By Tim Ross

Several shear failures were observed in Shaft #1 at the Mountain Coal Company, LLC, West Elk Mine, after mining longwall Panel 23, 1,100 ft to the east of Shaft #1. It was speculated that this shear damage could be related to differential ground movement caused by in situ stress relief from the ?stress shadow? of the caved zone above longwall Panel 23. A numerical study was conducted to assess the possibility of the shaft shear damage being caused by in situ stress relief and the potential for additional damage to Shaft #1 and two other nearby shafts, due to mining nearby longwall Panel 24. Three-dimensional (3D) models were built in FLAC3D to simulate past and future mining near shafts, the estimated local anisotropic and directional horizontal stresses, and the overlying variable surface topography. The numerical analyses indicated that stress relief due to mining Panel 23 caused the shear damage to Shaft #1and that additional damage to Shaft #1 and the other two shafts, would likely result from mining longwall Panel 24. Additional shear damage was documented in Shaft #1 when longwall Panel 24 was mined, confirming the results of the numerical analyses.

Jan 1, 2006

By T Sparks

The Collie River catchment, located approximately 200 km south of Perth, covers an area of around 2830 km2 and is the source of run-off to the Wellington Dam, an important irrigation water resource for the Collie Irrigation District. The salinity of the Wellington Dam has increased due to historical clearing and irrigators currently use water with salinity levels approximately twice that of the Murray River in South Australia (Water and Rivers Commission, 2001). The Collie River Salinity Situation Statement (2001), released by the Water and Rivers Commission (now the Department of Water), identified realistic actions that could achieve the salinity reduction target. Subsequent benefit-cost analyses and prefeasibility studies recommended the diversion of the most saline flows in the Collie River away from the dam as an immediate intervention (URS, 2003). The East Branch of the Collie River above the locality of Buckingham (20 km east of Collie) contributes around half of the salt that flows into the Wellington Dam and the diversion and storage of the saltiest flows from the East Branch at Buckingham was identified as a viable option for reducing salinity in Wellington Dam. The proposal had one problem û the water could not be disposed of as quickly as it was diverted. However, in the vicinity of the diversion site were a number of coal mine voids and after preliminary discussions, the Government/Griffin Coal alliance was formed and from this the opportunities have continued. Diverted water would be stored temporarily in an adjacent mine void (Chicken Creek 4 void) and then disposed of to the sea. The disposal options included Western Power CorporationÆs saline discharge pipeline from Collie Power Station, or a new pipeline. The diverted water was also identified as a potential raw source for treatment and use in industry. This has opened up opportunities including desalination, water efficiencies in the power stations, increased reliability of water supply for the power stations, water for new industries, wastewater disposal options and extra water for PerthÆs water supply. In the process of solving the water storage problems the project introduced a range of mine water quality problems û heavy metals and pH û and the Department of Water (DoW) is now working with the mining industry and the Centre for Sustainable Mine Lakes (CSML) to develop treatment and management technologies. The project has received support and funding through the National Action Plan for Salinity and Water Quality (NAP) and it has been possible to accelerate and enhance this project as a result of NAP. The DoW has developed the proposal to an advanced stage and gained approvals for the capital diversion program to go ahead. The partnerships have expanded to include the second mining company, Premier Coal, the Water Corporation, Western Power and the Harvey Irrigation Cooperative. The proposal could feasibly result in a $90 million integrated water management initiative for Collie using the latest technology, mining operations and providing water for value adding industries in the local area. The DoW is not a mining company; however, our experience in managing water in times of shortage, environmental water quality criteria, competition for water and managing community expectations will have the same success factors:consultation and knowing your community and stakeholders, sharing issues and working in partnership can provide results far greater than the initial issue, even brackish water has value, every sector is in competition with each other and has to have a share of the water, an integrated approach can provide opportunities for development in areas of water shortage, and never think of water as wastewater.

Jan 1, 2006

Due to problems with old technologies more and more product designers have turned to liquid crystal (LC) displays, which have consequently experienced phenomenal growth. The success of liquid crystal displays has fostered continued development, to the point where full-color video displays have been realized which can rival. The details of the lens structure and of the devices fabrication and performance are described using the Jones matrix method. Director n can change from point to point and is, in general, a function of space.. The transition can be approached by changing the impurity concentration or, indirectly, by tuning the temperature since the pinning strengths of the random and crystal potential have in general a different temperature dependence. Light from the conventional light source or laser is passed through a polarizer and then incident on the specimen. The resist profile simulation is carried out using the combined data thus obtained. The nematic liquid crystal is clear only when a long range order exists, in the whole medium. At the nematic-isotropic, transition temperature, the medium becomes isotropic and looks clear and transparent.

Jan 1, 2006

By Stephen C. Tadolini

The International Ground Control Conference in Mining has always provided an open forum for the publication, presentation, discussion, and often heated debate on roof bolting systems mostly with attention to how, when, and why they work. During the last 24 Conferences at least 170 papers have been presented by International Experts on these ?simple? devices that range in length from 30-inches to 20 ft and from 5/8 to 2 inches in diameter. Roof bolts are primarily mechanically anchored, glued, cemented, or driven. Bolts are placed vertically, angled, or tied together with special fixtures (trusses and slings). They have been termed active, passive, stick-slip, and several other descriptive acronyms or mining slang expressions. This retrospective paper will present the changes in bolt types and usage, point out some of the biggest myths and hail the most significant advances (according to the authors? opinions of course).

Jan 1, 2006

By Peter Middendorp

Pile foundations are widely applied in the Netherlands because of the soft soil conditions. One of the popular pile types are cast-in-situ piles, which have to be integrity tested to get accepted. Integrity testing has been applied for more than 30 years, with the number of integrity test performed nowadays exceeding 400,000 per year and subsequently there is a substantial amount of practical experience with this testing method. This paper will deal with some basics of integrity testing and describe some of the techniques that have been adopted in the Dutch pile testing practice, like detection of pile head defects with a spike type hammer pulse, and the site average or pile group average for the qualitative interpretation of measured signals.

Jan 1, 2006

By M. B. Greyver

The results of laboratory tests on iron precipitation from non-decopperized nickel anolyte are discussed. The parameters (pH, oxygen consumption and stirring speed) for iron precipitation from the anolyte, using the oxygen in the air, were determined. In the experiments conducted under optimized conditions, the residual concentration of iron in the anolyte after precipitation was 0.7-2.7 mg/L, and the copper and nickel losses to the solid phase were 0.05-0.07% and 0.05-0.16%, respectively. The filtration ability of the iron slurry obtained was 2 to 5 times higher as compared to that after chlorine oxidation and oxyhydrolysis. The leaching of the non-ferrous metals from the iron cake made using the separate nickel anolyte purification process was possible by dissolution in sulphuric acid. It was established that after cobalt precipitation from the copper- and iron-depleted anolyte, the precipitates obtained had lower ratios of Fe:Co and Ni:Co.

Jan 1, 2006

By T Berryman

The Fimiston reserve is being depleted at the rate of one million ounces per year; most of which is processed by the Fimiston plant, with the remainder being stockpiled. As for most other large open cut mines around the world, Fimiston has an excellent dispatch and tracking system. Reconciliation is used to determine how the various models used in mine planning (such as a reserve, budget and schedule models) are tracking against production. It is also used to gauge the performance of grade control estimation against production; however, analysing the results of this can be complicated and, at times, misleading. The reconciliation process involves adjusting the monthly production data to equal the mill reported tonnes and grade, plus the change in stockpiles. This adjusted number is then compared to the grade control reported tonnes and grade, the scheduled model (monthly planning model) tonnes and grade and against budget (Reserve) tonnes and grade. This paper includes explanations of all assumptions made in the reconciliation process, including the end of month closing stocks balance, the application of adjustment factors to the dispatch data to create a new balanced set of production data and the monthly sign off to comply with the Sarbanes-Oxley requirements of the North American owners. The reserve is reconciled by proved and probable classification. This tool is used to assess the robustness of the classification scheme utilised and identify any reconciliation issues as they arise. Within the Fimiston deposit there are still issues that are clouded by the assumptions made concerning the scale of observation, poor data support and the mining of the narrow lode areas of the deposit. The declared ore mined (DOM) number (which is defined in the paper) can be significantly affected by these assumptions, and these need to be clearly stated and understood when looking at the reconciliation data. The DOM tonnes and grade is a good indicator of real mine performance as it adjusts mined tonnes and grade to take into account the milled tonnes and grade each month, and prevents cumulative errors from building up in mine predicted dispatch numbers or end of period stockpiles. This number allows monthly monitoring of the mine to mill performance and allows valid comparisons to be made back to budgets and reserves over a period of time. KCGM uses three month rolling averages to monitor performance against reserve and budget models. This ensures that monthly distortions in the figures due to stockpiling issues or over mining in a particular period do not lead to false conclusions. Reconciliation performance over a longer period (12 - 18 months) is used to adjust reserve models should significant variance be observed. By closely monitoring the reconciliation performance at the Fimiston operation, fine tuning of all aspects of the grade estimation process from reserve through to grade control can be made. This allows the most accurate data to be used when planning from reserve data for the Life of Mine Plan through to grade control data for short-term mill feed.

Jan 1, 2006

By Steve Kral

The mining industry in northern Ontario is known mostly for its huge nickel deposits. Inco’s and Falconbridge’s nickel mines in the Sudbury Basin are the best known. And with nickel prices being what they are, interest in the region continues. And how. Inco and Falconbridge want to merge. Teck Cominco wants Inco, but without Falconbridge. Xstrata made a hostile bid for Falconbridge, which Falconbridge rejected. And, in June, Phelps Dodge trumped them all when it made an approximately US$40-billion friendly offer for Inco and Falconbridge in a two-part deal.

Jan 1, 2006

By M. Hopf

The use of water-cooled copper components as sidewall elements of submerged arc furnaces and other pyrometallurgical applications has become increasingly common. The high cooling efficiency of copper has made it possible to increase the service life of furnace refractories when compared to conventional refractory linings. However, even the self-healing effect of ?freezing? worn areas of the lining does not necessarily protect the copper coolers against wear or corrosion completely. In order to avoid furnace explosions, various methods have been used to monitor the wear of coolers. Unfortunately, these have not been able consistently to identify localized wear. Thos Begbie (South African) and SAVEWAY (German) jointly developed technology to embed a line sensor into the copper cooler during the casting process. This system allows an exhaustive monitoring of the copper cooler. A SAVELINE sensor is placed inside the copper-cooling panel between the water-cooling passage and the hot face of the panel. The sensor follows the meandering shape of the cooling water channels. In the first instance, the sensor provides analogue information as the thickness of the copper reduces. Secondly, this wear signal will be confirmed by a signal of interruption if the sensor is washed away. Because of the structure of the sensor, a self-diagnosis is possible and indications can be confirmed (double proofed).Subsequent to the manufacture of some test pieces, coolers for a large submerged arc furnace were manufactured. The sensorized coolers have been installed at the intermittent surface (slag line) where the largest amount of corrosion has been encountered. The system has been operating since December 2005 in what is considered one of the largest submerged arc furnaces in South Africa. Keywords: Pyrometallurgy, furnace, copper coolers, freeze lining, monitoring, Saveway

Jan 1, 2006

By G. Mousavian, R. Bagheri, N. Dalili

Polypropylene (PP) and its composites have an increasing use in automobile and domestic industries. Since the published results on strain rate effect on yield behavior do not match, and there is a high attention paid for effect of nanometeric fillers on deformation behavior of composites, in this research the strain rate effect on yield behavior of PP and the effect of nanometeric fillers on deformation behavior of PP have been studied. Microscopic observations and tensile tests in different strain rates on neat PP samples and on samples filled with 5, 10 and 15 %wt have been used. A dramatic change in behavior for the modulus and post-yield slope curves when the strain rate is between 0.0433-0.05 s-1 has been observed. Microscopic observations on PP indicate a change in deformation mechanism from shear yield to crazing at the same strain rate that the change in behavior of curves occurs. It has been observed that in PP nanocomposites with higher amount of calcium carbonate, fracture in early stages of deformation occurs in lower strain rates. In other words for a fixed stain rate there is a critical filler percentage such that if the filler percentage is higher then early-stage fracture will occur. Similarly for a fixed filler percentage there is a critical strain rate and in higher strain rates early fracture will occur. The critical stain rate will decrease as the filler percentage increases and vice versa.

Jan 1, 2006

By Peter B. Lilly

Thank you, Syd, for the kind introduction and for inviting me to give the Keynote Address at this very prestigious gathering of some of the finest intellect and talent in the domestic and international coal industry. CONSOL Energy has been a part of this conference for its entire 24-year existence. We have presented 27 papers over that time. CONSOL employees have also been members of the planning committee for the conference, and we have been pleased to support the event both financially and with many participants. So I am honored to be here with all of you this morning, especially during such a positive period for coal. You can just feel the enthusiasm in this room for our industry, and for this conference. I can tell you, there?s also a lot of enthusiasm and excitement in CONSOL Energy?s boardroom. And our enthusiasm is mirrored on Wall Street. But there remains an ironic twist to all of this attention. Even when times are good, the coal industry seems to go largely unnoticed by the mainstream. Outside of West Virginia and other coal-producing regions, the industry still seems to lack influence and support, at least here in America. As an example, last month, an ABC News crew visited our Blacksville 2 Mine, near here, to do a feature story on increased employment in the coal industry.

Jan 1, 2006

By Gregory M. Molinda

Historically, miners have known that roof rocks originally composed largely of mud were prone to slaking and deterioration when exposed to water and humidity. Mine Safety and Health Administration (MSHA) records show that roof falls are more prevalent in summer and late fall. Field data shows higher bolt loads and increased room convergence in summer months. Laboratory data shows that very high internal pressures can be generated by significant strain in clay-rich rocks. In summer months humidities ranging from 70-100% can cause rock strains up to 7%, and rock pressures of 14,000 psi, more than enough to break apart weak shales and fireclays. The National Institute for Occupational Safety and Health (NIOSH) conducted wet/dry immersion cycling of clay-rich rocks. Results show that the rocks most prone to moisture deterioration are fireclays, claystones, and sandy shales, all of which have disrupted bedding. Of the 7 mudrocks with a weatherability index above 40%, none showed consistent fissile bedding. Black shales were surprisingly resistant to wet/dry water immersion cycling. Generally, mixed rocks (stackrock), typically susceptible to horizontal stress, are more resistant to moisture-deterioration. Mine roof rocks tested with moisture sensitivity ratings above 50% (moisture sensitivity index ranges from 0-100 with 100 being the most sensitive) all came from mines which had roof skin problems and used supplemental support to prevent rock fall injuries. Some roof rocks showed lateral variability of moisture sensitivity values, suggesting the need for more samples in highly varying roof rocks. Swelling strains of mudrocks showed that almost all of the swelling occurred in the first 24 hours after immersion. The wet/dry immersion cycling test used provides an accurate, quick and inexpensive method for estimating the moisture sensitivity of mudrocks. With this information mine operators can begin to anticipate hazardous ground and prepare appropriate roof support.

Jan 1, 2006

By G. Anger, J. Enser, H. Antrekowitsch, S. Koch

Homogeneous chemical composition and microstructure are always necessary, but not always attained in practice. As-cast aluminium alloys tend to have a segregation microstructure. Features of the cast structure, which affect subsequent processing or properties, can be altered by the homogenization. The main task of the Department of Nonferrous Metallurgy was to investigate the effect of homogenization treatment on precipitation hardening of aluminium alloys 6061 and 6082. The effect of the solution heat treatment (SHT) temperature on the mechanical properties was also analyzed. The homogenized and non-homogenized rolling slabs were produced according to the usual conditions and methods. The metallographic investigations were carried out on the as-cast samples, after homogenization, after the hot and the cold rolling mill, and after natural and artificial ageing. Then, Brinell hardness measurements and tensile tests were conducted on both alloys in order to examine the influence of the homogenization.

Jan 1, 2006

By M Haydon

How do you portray a large structurally and stratigraphically complex deposit to return a meaningful resource estimation, and produce a geological model that is useable for planning on a daily basis? The George Fisher Mine is located 22 km north of Mount Isa and forms part of XstrataÆs Zinc Group operations. It is currently a major producer of zinc, lead and silver in the region with an estimated total resource for all categories of 127 Mt at 100g/t Ag, 5.3 per cent Pb and 9.2 per cent Zn (June 2005). Production in 2005 totalled 2 647 492 wet tonnes for 317 699 kg Ag, 140 317 tonnes Pb and 230 331 tonnes Zn from underground operations. George Fisher (GF) consists of two deposits that are structurally complex on a mine scale, George Fisher North (GFN) and George Fisher South (GFS). Regional faulting has resulted in a 2 km long package of variably pyritic shale and siltstone that separates the deposits. This paper looks specifically at GFN. Distinct correlations exist between the two deposits based on stratigraphic matches; however, orebody characteristics, geometry and fault architectures differ significantly between the two. The deposits consist of multiple, sedimentary-hosted, stratiform orebodies from 2 to 25 m wide, separated by waste intervals of variable width. Each ore-waste interval is modelled as an individual geological domain. Structurally, George Fisher North (GFN) contains a series of major late-stage NE faults with dextral offset(s) of up to 130 m. Further complexity is added by NS, NW and NNE striking fault orientations that can produce either a loss or repeat of stratigraphy, local drag folding, orebody attenuation and block rotation. Due to this structural complexity and orebody offsets, domains at GFN are further divided into fault blocks (FB). The GFN model comprises eight FBs over a strike length of 1 km, all of which are modelled independently. As drilling progresses and additional resources are converted, further FBs will be added at major fault offsets to accommodate orebody and model expansion. This will be in addition to what is already a large and time-consuming data set to manage and update. For example, each FB has 18 domains each with two constraining wireframes (hanging wall and footwall). Each wireframe has several sets of point data depending on the type of data available, ie diamond drilling, mapping or interpretation points. This equates to over 1100 separate files to manage. Additional wireframes and files are also required for major structures, daily planning requirements and block model runs. In total some 1500 files are managed, updated and maintained for GFN alone. The ongoing need to expand as a business and optimise production in the current economic climate where there is a global demand for metal has led to an increase in production at GF. This has resulted in a rapidly growing data set and highlights the importance of practical and efficient modelling to achieve a meaningful resource estimate. This paper focuses on the geological modelling, modelling approaches and techniques employed for the GFN deposit.

Jan 1, 2006

By N Meadows, M Rodriguez

A 200 000 tpa heap leach demonstration plant was approved by the Murrin Murrin Joint Venture (MMJV) in December 2005 and engineering commenced in January 2006. The demonstration plant will utilise stockpiled ore reject material (æscatsÆ) and extract nickel and cobalt. Limited production from the demonstration plant is expected by the end of 2006. The demonstration plant will enable the company to fully investigate and understand all associated technical issues over the next 12 to 18 months, including the potential to expand the heap leaching operation to a commercial scale. In parallel, the MMJV will continue a research and development program to improve and expand the application of its heap leaching technology.

Jan 1, 2006

By P. Coulombe, J-F. Riverin, A. Gaboury

Cavity cleaning during anode change generates a material that consists of anode cover material and cryolite melts. This material is scooped and placed in bins for transport and further processing and recycling as fresh anode cover material. Typical processing methods in use involve cooling of the hot cavity bath in bins, with or without emission treatment systems, until it is adequate to be processed and grinded to the required particle size distribution. Handling of the hot and cooled cavity bath material can be labour intensive. It also generates significant air emissions which contain particulate and gaseous fluorides. With the advent of the Aluminerie Alouette smelter Phase II expansion, the hot cavity bath tonnage to be processed increased to 700 t/day and maintaining existing practices was not satisfactory. This article presents a novel process implemented at the Alouette smelter where cavity bath is processed as a hot material directly from the potlines ( 600-800°C range), sized, cooled and then processed in the existing cold bath treatment plant. The system is designed to process 36 t/h, is fully automated and requires limited monitoring from operations. Implementing this new system in a Browrifield environment imposed numerous constraints for space, interfaces with existing operations, commissioning and ramp-up. It is presently operating at approximately 80% availability and is easily meeting the requirements of the potlines. This system has significantly improved the workplace environment in the bath treatment area and reduced the overall particulate and gaseous fluorides emissions at Alouette. Aluminium 2006 45th Annual Conference of Metallurgists ofCIM Montreal, Quebec, Canada Edited by

Jan 1, 2006

By Ludovic Charpentier

Production of metallic wires directly from liquid jets would avoid drawbacks of extrusion (space needed, damaging, cost?) and enable recycling. But liquid jets tend to break, due to capillary instabilities, unless a solid layer (coating or start of solidification) surrounds it. We recently developed a process to produce tin wires, cooled by water flow parallel to the jet. Superficial oxidization of tin produces a glass coating around the jet. Studies showed the length of wires increased when increasing speed of tin jets, and that water average speed should be the closest possible to the jet one to have smooth fibers. Producing 1 mm diameter wires is possible. The length of wires is limited by the experimental setup, which does not provide possibilities to coil the wire. Most of other metals do not generate glass-like oxides. The lack of coatings makes it necessary to reduce the capillary instabilities to obtain fibers.

Jan 1, 2006

By R R. Lovel

In this paper, life cycle assessment methodology has been used to assess the variations in water use associated with different metal production and processing routes and provide insights into the value derived from water usage in the minerals sector. Using water consumption data derived from the literature it has been shown that the æcradle-to-gateÆ water consumption (or embodied water) for production of the various metals considered in the study ranged from 2.9 m3/t for steel up to 252 087 m3/t for gold. The results largely reflect the grade of the initial ore used to produce each metal, and can be approximated by the following equation:W = 167.7 G - 0.9039 where: W = embodied water (m3/t refined metal) G = grade of ore used to produce metal (per cent metal) The study showed that indirect water consumption in the metal production life cycle, in particular that due to electricity generation, can make a significant contribution to the embodied water value, eg aluminium production. When expressed in terms of m3/t ore, the results for all metals considered indicated that the embodied water is roughly, on average, three times the water consumption of the mining and concentration stage. It was also shown that the economic value per m3 of water consumed for the minerals industry exceeds that for the agricultural and industrial sectors, supporting the view that allocating water resources to the minerals industry has a strong underlying economic basis. Water reforms currently taking place in Australia aim to address issues such as competition for water access, reduced security of supply and increase in cost. Consequently the minerals industry, along with others, can be expected to come under increasing pressure to reduce fresh or raw water use and to integrate water use across sectors. While water recycling is an obvious candidate to help reduce water consumption in the minerals industry, issues such as water quality, among others, will influence the extent to which this can be achieved. In addition, wastewater volumes can be minimised using techniques such as pinch analysis to establish and use the minimum water requirement for the process. The use of dry or near-dry processing technologies, for which the demand for water is small or zero, may be a more radical solution to the water consumption problem; however, it is possible that the introduction of dry processing would bring with it a new set of problems, including dust.

Jan 1, 2006