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Seven papers included in Session 8 of the Third International Mine Water Congress under the heading "Achievements in Mine Water Management & Research" have been reviewed. Only one paper, a case study by Masters on biological treatment of inorganically polluted effluent, has any connection with research in the sense of seeking new, generally applicable knowledge which would advance the frontiers of mine water management. The remainder deal with various aspects of the management of mine water ranging from investigation of the geology of a specific aquifer system through operating dewatering systems to the management of specific effluent disposal problems.

Jan 1, 1988

Zircon producers are often required to lower impurity levels to meet customer specifications as most of these impurities adversely effect the end use. For example, zircon sand in foundry applications needs to be free of any surface impurities (eg clay, gibbsite and goethite) which otherwise could cause sintering or fusion between cast metal and the zircon mould. Light coloured ceramic grade zircon, typically low in iron oxides and titania, is preferred in ceramics applications. The presence of impurities in zircon sands is a problem in the magnetic and electrostatic separation stages of their concentration. Previous work (Aral et al, 1997) showed that impurities in zircon sand concentrates occurred in the form of stains on grain surfaces, discrete gangue minerals and in the mineral grains. The gangue minerals such as rutile, garnet, xenotime, monazite, spinels, ilmenite, and aluminium silicates in the concentrate in some cases (Aral et al, 1997) contribute significantly to the impurity content of the concentrate. A careful hand picking of the impurity grains from a Western Australian zircon sand showed that the impurity content of the concentrate could be lowered significantly as a result of the removal of the surface stained grains and gangue minerals. The hand-picked ædirtyÆ fraction, comprised about eight per cent by weight of the concentrate, and consisted mostly of iron-oxide/hydroxide-stained zircon, silica grains and rutile, and occasionally ilmenite, monazite, gahnite and other (unidentified) coloured grains. The chemical analysis of the remaining æcleanÆ fraction showed that the major impurities (Fe and Ti) were reduced significantly (Table 1). The reduction in the uranium content was about 30 per cent. The other measured impurities, P, Mg, Al, Th, and Ca remained mostly unchanged as shown in Table 1. The contribution of ilmenite to the overall iron content of æcleanÆ zircon was insignificant as it comprised about 0.1 per cent weight of the æcleanÆ zircon. Rutile was the major source of titanium contamination (about one per cent by weight). Recent work (Aral and Calle, 1999) on zircon sand concentrates from the Murray Basin showed that, under the electron microprobe, the bulk of the impurities occurred in the dark back scattered electron (BSE) regions of the zoned zircon grains. The impurity contents of the light BSE regions and unblemished (unzoned) grains were low. The impurity content in zoned zircons has been investigated on single, relatively large, crystals (McLaren, Gerald and Williams, 1994; Smith et al, 1991; Romans, Brown and White, 1975). These studies generally aimed to investigate the incorporation of U in zircon as zircon is used extensively for U-Pb geochronology owing to its relatively high content of uranium. Smith et al (1991) identified a striking difference in composition between the areas of lower (dark BSE) and higher (light BSE) average atomic number in the zoned zircon. Their work showed in particular that the zones of lower atomic numbers contained very significant amounts of trace metals such as Y, REE, Nb, U, Al, Fe, Ca, Ba and, by difference H2O. In this paper the impurity distribution in zoned zircon grains was investigated on statistically significant number of grains before and after a leach treatment. The distribution of impurities was also measured in unblemished areas to compare the results.

Jan 1, 2000

By Cunningham J. C

JUST prior to the war the Broken Hill South Ltd: raised, on the average, 6628 tons of ore per week, all of which was crushed and treated in the 4-section gravity mill and the slime flotation plant, for the recovery of lead concentrate carrying silver. The sandy residues from that treatment were railed to the treatment plant of the Amalgamated Zinc (De Bavay's) Ltd. for the recovery of zinc concentrate by flotation, on the joint account of both companies. Subsequent to that-since 1916-approximately 1000 tons of old dump slime were also treated weekly for the recovery of lead and silver as slime-lead concentrate.PLANT CAPACITYUnder this programme the Babcock and Wilcox boiler plant of 8 boilers was taxed to such an extent as to call for the installation of two additional boilers, each of 2690 sq. ft. of heating surface and 55 sq. ft. chain-grade area.The electric generators and the air compressors of the old powerplant were also loaded to their maximum capacity. In view of the fact that the old power-plant had been added to from time to time since 1901, and that further extension was notpossible, and as it was not, moreover, an economical arrangement, the whole question of power generation was reconsidered. The considerations that determined the installation of entirely new plant were as follows:(1) The need for more compressed air for underground work and more electric current for the extension of the slime-flotation plant for the recovery of zinc, as well as lead, as slime concentrates. Provision of additional power was also deemed advisable for the...

Jan 1, 1921

The epizonal Ag-Pb-Zn vein deposit at San Bartolome is characterised by a base-metal sulphide assemblage containing the spectacular development of interpenetrating, bladed networks of pyrrhotite which have been replaced by marcasite and pyrite. A similar assemblage displaying the same crystal habits and textures are also a diagnostic feature of the Sn and SnAg deposits ofBolivia. On this basis, it is reasonable to conclude that both deposits were formed from fluids of similar nature and origin. Although no economic accumulation of Sn is known in San Bartolome, further comparison of the geologic setting, age, mineralogy, fluid inclusion data and magmatic association of this deposit with the Bolivian systems has highlighted additional similarities consistent with a hypothesis that more extensive Sn mineralisation might exist in the San Bartolome area.

Jan 1, 1995

Mining in Guyana dates back into antiquity and a brief history of gold and diamond mining and of the small-scale miner, the pork-knocker, is given. The gold and diamond deposits found on the beds and in the flats of old and present rivers and the current methods of investiga- ting these deposits are briefly described. Methods of mining these deposits including the small-scale hand methods of pitting and diving with or without helmets are also briefly described. 'The small-scale method of dredging using a suction dredge in conjunction with a diver is described in more detail, from its develop- ment to current practice, without giving too much mechanical and technical details. The organisation of the industry and the mining titles, laws and policy relating thereto are reviewed. A brief account is given of the socio- economic role of the industry. Conclusions are made regarding the need for improvements in existing equipment and financing and for incentives to stimulate production. The future outlook of the industry is con- sidered.

Jan 1, 1986

Key blocks occur on the surface of excavations and on the walls of the ornamental stones and limestone quarries due to the formation of joint planes, fissures, microfaults and quarrying operations. Movements of these key blocks have produced numerous important failures and are responsible for routine overbreak and rock falls accounting for great costs. The thrust of this work is to demonstrate how to delimit zones of poten- tial key blocks (danger zones) in the wall of Bani-Khalid quarry of lime- stone by using the block theory technique (stereographic projection). The final result of this study indicated that, there are three potential key blocks, the most critical one has been determined. To treat the problem, we sug- gest either to provide timely support to prevent the movement of this block, or to analyze it further in hopes that available friction on the faces will hold it safely in place.

Jan 1, 1989

By Dixon CA

In the early 1970s, Jim Walter Resources, Inc. (JWR) embarked on a coal mine expansion program that was unparalleled in the history of the United States. With a small nucleus of people then operating two rapidly depleting captive mines, action was initiated to develop four of the deepest mines in the United States. Because of the depth of these mines, operational and technical problems were anticipated. However, because of the high quality of the coal (Blue Creek Seam), the financial risks involved were acceptable. The total investment to get the expansion program completed (to get the new mines to full capacity) would represent an investment of over US$ 500 million.By the end of the decade of the 1970s, the Company had grown to 2100 employees who were producing 1640,000 tonne of saleable coal per year, a productivity rate of 3.9 tonne per man-shift. This productivity rate was not sufficient to maintain a profitable, viable organisation. Therefore, if the operations were going to survive, it would be necessary to improve productivity tremendously, a task which would tax the resources and imagination of all employees.

Jan 1, 1991

By Kellerwessei H, Oberheuser G

A major breakthrough in extending the life of the wear material of high pressure roll crushers when treating moist, highly abrasive material has removed the last impediment to the widespread acceptance of high pressure comminution in the minerals industry. The system is very energy efficient. It has been demonstrated that in the cement industry energy savings of up to 50 per cent have been achieved compared to conventional hall milling. Besides being energy efficient, the process provides some remarkable and useful effects; ò better liberation of mineral constituents (as proven for diamond liberation). ò preferential comminution where induced micro fissures follow grain boundaries. ò higher reactivity of the product due to micro fissures. All these points will be described here together with a review of current flowsheet design and incentives for the use of this method of Comminution.

Jan 1, 1993

Over the past five years, dedicated tertiary mining engineering programs have become financially unsustainable in Australia on the basis of undergraduate enrolments alone. The situation is worse in other minerals related disciplines and extends to the technical minerals education sector. This paper reviews the causes for the current situation. Indicators are presented which suggest that enrolment trends can no longer be attributed only to business cycles in the minerals industry but are also reflective of a fundamental shift in student interest in the sciences and resources based engineering disciplines. Reactive responses to changing trends are diluting and compromising the quality of mining engineering education. It is unlikely that the trends can be reversed or resisted. Tertiary minerals educators need to position themselves so that they can be responsive to on-going change. Two proposals are offered which aim to anchor mining engineering in a long-term sustainable manner. The proposals have a common educational component which is concerned with restructuring how mining engineering programs are presented and providing more flexible access to such programs. However, the two proposals have significantly different commercial components. The commercial component of first proposal is concerned with working within the traditional education framework of universities to endow a critical number of core staff positions. It effectively equates to fund raising. The second proposal is concerned with developing a stand-alone commercial operation around the education and research advantages of the global and multi-disciplinary university system. As a shareholder in this business, a university department would earn dividends that it could then use to support its education initiatives. This proposal provides a performance-based mechanism for supporting university minerals programs and has the potential to be cost-neutral. Both proposals are suited to resource sharing with a select number of international mining schools and to the incorporation of the other tertiary minerals disciplines under threat.

Jan 1, 2000

By D Garcés, M Meléndez, R Castro, E Viera

Enhancing the understanding of gravity flow in caving operations is a key factor in the design, operation and success of caving methods. Consequently, much research has been performed to increase knowledge about gravity flow. Many valuable theories have been gained from different research approaches, which include physical modelling, numerical modelling and a limited number of full-scale tests. Recent advances in technology have allowed Codelco Chile to carry out trials using Smart Markers technology. This technology was used in Esmeralda mine’s Block-2 at El Teniente mine from August 2012 to January 2015. This paper aims to determine the characteristics of the extraction zone and obtain the data that will allow greater understanding of gravity flow for design and draw control purposes.The collected data from recovered markers were analysed using a linear interpolation of both the initial position of the markers and drawbell accumulated drawn tonnage. For each drawpoint in the trial, the regularity or irregularity of flow was analysed based on the recovered markers and the drawn tonnage. Correspondingly, the relationship between flow characteristics and observed fragmentation in drawpoints was analysed. The gravity flow of the Smart Markers revealed that current drawpoint spacing provides the interaction conditions of adjacent flow zones. However, it is possible to increase the drawpoint spacing while allowing caved rock to be extracted from the major and minor apexes.The results of this research also verified that full-scale test data are the predominant factor in the production level design and production control at El Teniente mine.CITATION:Garcés, D, Viera, E, Castro, R and Meléndez, M, 2016. Gravity flow full-scale tests at Esmeralda Mine’s Block-2, El Teniente, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 349–358 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By R Wynn, N Stoitis, R A. Lauten, H Liang

At the Century mine in North West Queensland, MMG produces lead and zinc concentrates. The current production rate is close to 500 000 t of zinc per annum. Graphite is the main gangue in the orebody and a substantial quantity of chemicals are used to achieve an acceptable depression of graphite and other gangue materials in the current operation. In the future, it is anticipated that the content of graphite in the orebody will increase while the zinc grade will gradually drop. This scenario illustrates the importance of an optimised suite of flotation chemicals to maximise concentrate grade and recovery. As an alternative to the current reagent suite where dextrin is used to depress graphite, laboratory test work and subsequent plant trials were conducted with alternative depressants. These depressants facilitated both graphite depression and elevated zinc grades in the rougher concentrate. As an added benefit, it was also observed that the silica content in the zinc concentrate was reduced in the presence of the biopolymer selected for the plant trials. Results from both laboratory tests and plant trials will be discussed to illustrate how this change of reagent suite improved flotation yield at the MMG Century Mine.CITATION:Wynn, R, Lauten, R A, Liang, H and Stoitis, N, 2014. A change in graphite depressant to improve the recovery of zinc at MMG Century mine, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 179–186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By Y Xie, D Willingham

Predictive maintenance (also known as ‘condition/health monitoring’) refers to the intelligent monitoring of equipment to avoid future failures. In contrast to conventional preventive maintenance, the maintenance schedule is not determined by a prescribed timeline; instead, it is determined by analytic algorithms, such as machine learning, using data collected from equipment sensors and/or via simulation.Predictive maintenance offers the following benefits for operators and equipment manufacturers:- reduces equipment downtime by identifying issues before failure, thereby enabling convenient scheduling of equipment service and extending equipment lifetime- determines the root cause of the failure, enabling appropriate service to be performed without utilising resources to determine a diagnosis- avoids the unnecessary costs of maintenance and unexpected failures- improves safety and product quality.Algorithms and data are critical to predictive maintenance success. Sensor data is first preprocessed using advanced statistical and signal processing techniques; it is then combined with predictive modelling techniques, such as machine learning, to estimate equipment health.Once tested, predictive maintenance algorithms may be used in an operational setting within an IT environment, such as a server or cloud. Alternatively, algorithms may be implemented in an embedded system directly on the equipment, allowing for faster response times and significantly reducing the amount of data sent over the network.CITATION:Willingham, D and Xie, Y, 2017. Predictive maintenance modelling for bearing-based equipment, in Proceedings Iron Ore 2017, pp 627–630 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Skinner A. J, Thoman B. C

The general structure of microprocessors and their method of use is described, and de- tails given of their application in two parti- cular examples of instrumentation for mineral concentrators. One is in a pulp density gauge, and using this example, the way in which a microprocessor-based unit can be made to be self-calibrating is described. The other is in an on-stream analysis detector for uranium in solvent, where a microprocessor is used to re- place a mini-computer.

Jan 1, 1977

Economic evaluations of mineral projects are based on discounted cash flow analyses, followed by sensitivity and risk analyses. However, the global macroeconomic and political environment in which the mineral industries operate have a profound effect on the viability of individual projects. Since the oil crises of 1974 and 1980, demand patterns for minerals have become much more variable and prices more volatile. Significant changes in the geographical distribution of world mineral supply and demand are underway, and the mix of minerals used is also changing. Social and political factors are as important as economic and technical factors in determining the viability of mineral ventures. Economic evaluation of mineral projects have to be undertaken in a more uncertain and risky environment. They can no longer be reduced to a number crunching exercise.

Jan 1, 1987

By V Lishchuk, C Lund

"Geometallurgy aims to improve resource efficiency by creating a spatial model of an orebody in order to forecast ore processing behaviour. This enables calculation of the economic value of each ore block and the use of this information for production optimisation and hence an improved economic return. Modelling uses different approaches to link geological information with mineral processing: traditional approach uses chemical elements; proxy approach – small-scale geometallurgical tests; and mineralogical approach – minerals.A geometallurgical model is obtained during execution of a geometallurgical program encompassing the entire value chain of ore processing. Available methods for establishing a geometallurgical model are in many cases limited and not yet comprehensively validated. Some of the limitations include: sampling density, assaying methods and quality, forecast accuracy block model content, geostatistical solutions for non-additive components, blending and assessment of positive impact of geometallurgy on the project. Synthetic ore models combined with process simulations and production scheduling, based on strong case studies, present a viable way to address these shortcomings. Such synthetic ore models will have realistic elemental and mineral distribution, textural attributes and 3D variability for input into the design of an appropriate geometallurgical program.A synthetic orebody was created for an apatite-bearing iron deposit. Variability in modal mineralogy was described by geostatistical parameters combined by a set of linear and trigonometric functions. The generated synthetic deposit model was used to develop a mine production plan to generate a simulated process feed. The process feed had detailed information required for beneficiation process simulation: modal mineralogy, chemical composition of minerals, grain size and specific gravity. The synthetic system was used to measure benefits that a geometallurgical program developed for real cases could provide, compared to production where only head grade is optimised. These include a reliable sampling strategy and confidence in the feed-quality forecast for economic evaluation.CITATION:Lishchuk, V, Lund, C and Lamberg, P, 2016. Development of a Synthetic Ore Deposit Model for Geometallurgy, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 275–286 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

Gold mineralization belt of eastern China in the adjacent part of the northwestern Pacific rim is orientated NE to NNE and as-sociated with Mesozoic faults and igneous intrusives and Mesozoic to Cenozoic volcanism and subvolcanism extending more than 3000 km in length and 300 to 800 kni in width affected by the movement from the Pacific Plate subducted against the Asian Plate.The relative movement between the Pacific and the Asian plates give rise to two types of fracture zones, the tensional ones providing the space for the formation of fissure-filling type of auriferous quartz veins and the shear zones providing the space for the formation of hydrothermal replacement type of gold de-posits in Shandong Peninsula. The fissure filling type of quartz vein, is represented by Linglong gold deposit which is hosted in Mesozoic Linglong Granite and consists of hundreds of quartz veins filling fractures trending NE to NNE and the hydrothermal replacement type is represented by Sanshandao gold deposit which is hosted in crushed and hydrothermally altered Mesozoic Linglong Granite in contact with Archaean metamorphic complex of Jiaodong Group along a Mesozoic upthust fault zone trending NE.

Jan 1, 1990

The addition of a thallous salt to the cyanide leach of a calcined pyritic concentrate causes a marked increase in the"rate of extraction of gold. This probably is due to the activation of passive gold by.th,e. thallous ions'.''Lea'd, bismuth, and mercury salts, which should produce ' a, similai effect, fail to do so. It is postulated that'this latter result, together with'the reprecipitation of silver at low cyanide levels, is due to the presence of soluble sulphide. The use of thallous salts to reduce leaching time is discussed briefly.

Jan 1, 1964

This paper describes the oil engihe plant owned and operated by Gold Mines .of Kalgoorlie Limited, and gives some details of installation, operational, and maintenance experiences which have arisen during the years of service, the last 5 years of which have been under the writer's control. Nos. 1, 2, 3 and 4 alternator units have run 50,276, 48,006, 49,677 and 25,930 hours respectively, and much knowledge has been obtained of their performances and faults. During the war years, it has not been easy to obtain spare parts; this, coupled with the loss of No. 4: alternator unit to the Commonwealth Government, made operation and maintenance a very difficult problem.All engines are of the enclosed vertical, single acting, 4-stroke cycle, airless injection type.The electrical power plant originally consisted of four 6-cylinder Belliss & Morcom heavy oil engines, direct coupled to Bruce Peebles alternators, running at 375 r.p.m., and generating 3-phase electric power at 3,300 volts, 50 cycles.No. 1 unit, installed in 1936, is a 6-cylinder 450 b.h.p. standard 12A Belliss & Morcom heavy oil engine, direct coupled to 280 kw. 0.8 p.f. alternator. The remaining three units are 6-cylinder, 660 b.h.p., lSA oil cooled piston type Belliss & Morcom heavy oil engines, direct coupled to 410 kw. 0.8 p.f. alternators, making a total capacity of 1,510 kw.No. 4"alternator. unit, an 18A Bellis.& Morcom set, was taken over by the Commonwealth Government in June 1943.

Jan 1, 1945

By Gillies A. D S, Just G. D

The advancement of computer applications in the coal industry is focusing interest on the presentation of washability data by mathematical functions.The normal method of presenting washability data is in the form of five curves, usually filled by eye or by cubic spline functions. It has been shown that coal washability can be characterised by two basic relations: the instantaneous ash vs relative density relationship and the instantaneous yield vs relative density relationship. In a new approach to the mathematical modelling of the instantaneous ash vs relative density relationship, theapplication of the algorithm to a data set from a mine in central Queensland was successful.

Jan 1, 1991

By Vassiliev P

Cut-off optimisation, based on the work of Lane (1988), can be used to maximise the NPV (Net Present Value) of a mine by the judicious manipulation of cut-offs and the use of stockpiles. Apart from maximising NPV, cut-off optimisation will ver

Jan 1, 1998