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By A M. Wala, H W. Wu

A research project incorporating a number of mine site exercises to reduce the effects of fire incidents and possible consequent health and safety hazards has been undertaken focused on the application of mine fire simulation software packages for contaminate tracing and fire modelling in coal and metalliferous mines. This paper examines aspects of introduction of inert gases to underground workings to aid recovery of a mine following a fire. Broad conclusions from work undertaken at individual Australian coal mines are discussed as examples. The effort is built around the introduction of the fire simulation computer program æVentgraphÆ to the Australian mining industry and the consequent modelling of fire scenarios in selected different mine layouts. Case studies have been developed to examine usage of inertisation units and particularly application of the GAG jet engine unit. One example has focused on selection of the best surface portal location for placement of the GAG for most efficient suppression of a fire. A second has examined a situation with significant seam gas being emitted on the face. This has shown that under certain face dip angles stopping the mine surface fan to reduce dilution of GAG exhaust gases will cause reversal of face air and consequent mine explosion as gas laden air is drawn across a fire. A third examines inertisation and dilution issues in mains headings. mains headings present a complex ventilation network with often numerous parallel headings, hundreds of cut-throughs and a variety of ventilation control devices. In such a complex system (with additional interference from a fire), maintaining control of the movement of inert gas is more difficult than elsewhere in the mine. Some illustrations of this issue are given.

Jan 1, 2005

Boring of a 7.5Km long tunnel under the city of Stockholm commenced in January, 1987. The 3.5m diameter tunnel will pass under the buildings and as no ground settlement is allowed, the regulation for water leakage into the tunnel is very strict. Probe drilling will be carried out continuously ahead of the boring and when water is encountered the rock has to be grouted before passing with the TBM. The tunnelling system enables probe drilling to be carried out during boring with the TBM. This has earlier been a capacity reducing factor as the whole operation has been stopped during probe drilling. The project is using a new generation TBM especially developed for hard rock formations which require higher thrust per cutter to get a high penetration rate.

Jan 1, 1987

This paper discusses the recently com- pleted TBM-driven pressure tunnel at the Sand Bar Hydroelectric Power Project. The Sand Bar Project is a diversion scheme situated on the middle fork of the Stanislaus River in the Western Sierra Nevada, California, U.S.A. As part of the project, a 5.6 km long and 3.71 m diameter unlined pressure tunnel was bored by a Jarva TBM at the average rate of .37.5 m/ day. This report deals with construction aspects of the tunnel, including TBM performance, lining design, and remedial support measures. Correlations between TBM performance, geologic conditions, and rock properities are made, and the Contractor's mode of operations are discussed. Advance rate prediction, and the impact of these excellent advance rates attainable in hard rock using the new machines are discussed.

Jan 1, 1987

By Siemon J. R

It is possible to use compacted anodes formed at low pressure for the direct electrowinning of lead from sulphide concentrates. An anode containing 5.5 per cent graphite, formed into a compact at 34 MN m-2, enables lead to be won at a current efficiency of about 80 per cent; the power consumption .at 150 A m-2 current density being 0.4 kWh per kg lead. It would be necessary to use diaphragm cells to obtain a sufficiently pure product. A conceptual design for a full-scale plant is presented, together with a cost estimate for the production of lead by a process based on direct electrolysis of compacted concentrates. It is unlikely that the proposed process will be economically competitive with the conventional lead smelting.

Jan 1, 1976

By Quayle J. E

This paper covers period from 1973 through to 1988 and the mines of West Coast Mines, Elur Mine, North Mine and Risdon Zinc Smelter, now all part of the Pasminco Group. During this period, optimisation started with one mine (West Coast Mines) producing four Product concentrates with constant steady feed to the smelter and progressed to three mines producing eight products and a smelter varying feed inputs to maximise benefits. The initial optimisation was done manually using a desk top calculator and hand drawn graphs. This ultimately advanced to the use of PC plus linear programming software and spreadsheet generating relevant graphics. The financial benefits were achieved with no capital expenditure and increased from an initial $0.5 to $1.0 M/year (1973 $'s) to $5 to $10 M/year (1988 $'s).

Jan 1, 1991

Prefeasibility planning and cost estimation of conveyor systems has historically been undertaken by comparing fi xed plant transport requirements to that of similar systems in service. This paper describes the development of a prefeasibility conveyor technical design and cost estimation application using Microsoft Excel Visual Basic for Applications (VBA) platform. The application tool known as D-Convey (Dachshund Convey) was developed with the goal enabling the end user: to develop a technical model for conceptualised conveyor systems, to perform economic analysis on the developed technical model, and to conduct a comparative and risk analysis. An Excel VBA based platform was utilised to draw upon both the analytical and graphical capabilities of a spreadsheet. Some of the features of D-Convey system include a revolutionary dynamic graphical help system, known as the 'information pane' in lieu of traditional help fi les as well as the use of familiar graphical user interface elements such as the MS Offi ce 2007 task ribbon. The D-Convey system incorporates material database allowing for mass handling prefeasibility estimation in other industries; it has been validated at a local quarry.

Dec 6, 2010

Both the miner and the Regional Water Board have legal obligations to ensure that all discharges of water from a mine site are free of harmful wastes, and that proper authorisation is obtained to abstract, divert, or discharge water. This requires long-term planning of water management for the whole of the mine site. Guidance is given in the paper on the issues which must be covered in water right applications.

Jan 1, 1986

By S Q. Liu, E Kozan

This paper proposes a new multiresource multistage scheduling problem for optimising the open pit drilling, blasting and excavating operations under equipment capacity constraints. The flow process is analysed based on the real-life data from an Australian iron ore mine site. The objective of the model is to maximise the throughput and minimise the total idle times of equipment at each stage. The following comprehensive mining attributes and constraints have been considered: types of equipment; operating capacities of equipment; ready times of equipment; speeds of equipment; block-sequence-dependent movement times of equipment; equipment-assignment-dependent operation times of blocks; distances between each pair of blocks; due windows of blocks; material properties of blocks; swell factors of blocks; and slope requirements of blocks. It is formulated by mixed integer programming and solved by ILOG-CPLEX optimiser. The proposed model is validated with extensive computational experiments to improve mine production efficiency at the operational level. The model also provides an intelligent decision support tool to account for the availability and usage of equipment units for drilling, blasting and excavating stages.CITATION:Kozan, E and Liu, S Q, 2014. An Open pit multistage mine production scheduling model for drilling, blasting and excavating operations, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 329–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By Faidel VV, Yushina TI, Yagodkina NG, Yatsimirsky AK, Chanturiya VA

Among the problems of the flotation of sulphides by the thiol collectors is the dependence and varieties of the flotation starting with the time and oxygen contents in the slurry. For sulphides, the flotation stage follows after the electrocatalytic oxidation of the collector with oxygen on the surface of the conductor minerals. The necessity of the oxygen for sulphide flotation (Plaksin and Bessonov, 1957) is in accordance with a corrosion model of a collector surface sorption (Salamy and Nixon, 1954). As Golikov and Nagimyak (1961) showed, the sulphides possess catalytic activity which provides the autoxidation of the xanthates in the sluny to the dixanthogen. This stage can be rather protracted, which limits the speed of the total process. Disulphides constitute important collectors for the sulphide flotation and the optimal degree of the xanthate oxidation is about 20 per cent for different ores (Abramov, 1978) or, following Chanturiya and Nazarova (1977) the surface compositions for various sulphide ores are different and an optimal oxidation degree is variable from five to 25 per cent according to the ore nature. The optimisation of the surface composition is possible by application of the dixanthogens, or by a partial chemical, electrochemical, or catalytic oxidation of xanthates (Desains, 1847; Schall, 1896; Vigdergauz, 1989). According to Rand (1977) and Vigdergauz (1991) sulphides possess different catalytic activities for oxygen electroreduction. In neutral solutions, for example, the following decrease in the order: FeS2 (Fe,Ni)9S8 CuFeS2 FeS; Cu5FeS4 Cu2S; PbS (Vigdergauz, 1991). For the cases of low catalytic activities of the sulphides, the preflotation oxidation of xanthate could be useful to optimise the process kinetics.

Jan 1, 1993

By C Li, S Wang, L Qiao

Jinchuan nickel mine is the largest nickel mine in China. Cut-and-fill mining method with high density cementing materials is used in the mine. The original mining design divided the mining operation into two steps. The first step stopped the mining rooms and the second step stopped the pillars. Because the two-step method made big trouble for finally mining pillars and strongly limited the mining speed and production, it was successfully changed to a continuous cut-and-fill method without pillars. However, the mining operation in the mine has been down to 800 m and the mining condition is getting worse and more complicated. Through systemetical field investigations and 3D FEM analysis, it is proved that the mining method without pillars is feasible for mining deeper orebodies in Jinchuan nickel mine.

Jan 1, 2000

The Sishen iron-ore-mine produces 3 pro= ducts with size gradings of 25 to 8 mm, 11 to 5 mm and 5 to 0,2 mm and has a product capacity of 20 Mtpa. Ore is produced at an average Fe content of 66,2 % Fe for the two coarser pro= ducts and an average of 65,3 % Fe for the fine ore product. Three stage crushing is practised to re= duce the run-of-mine ore to -90 mm after which it is screened into five different size frac= tions of which four are heavy media beneficiated in static baths and cyclones and the fifth frac= tion discarded to slimes dams. A final three stage crushing and screening process is employed to produce the final three Products which are homogenized by means of blen=ding systems nrinr to despatch.

Jan 1, 1987

By G J. Harbort, V Lawson, L Reemeyer

The Jameson Cell is a high intensity flotation device, which utilises induced air from the atmosphere. It was developed jointly by Mount Isa Mines and Professor Graeme Jameson of the University of Newcastle in the 1980s. It is proven to generate fine bubbles, in the order of 300 to 500 ¦m, in a high intensity, high shear and compact zone contained in the downcomer. This aerated mixture exits the downcomer into the pulp zone, which is the quiescent mineral and gangue separation zone. A number of Australian base metal flotation circuits feature a reverse flotation stage at the head of the circuit. Testwork and plant operating data has shown that the use of a Jameson Cell in the prefloat cleaner application has further improved prefloat gangue recovery and selectivity. Operation of a Jameson Cell in a carbonaceous/pyrite prefloat cleaner duty at the Mt Isa copper concentrator increased copper recovery and reduced pyrite in the copper concentrate. Testwork at Zinifex Century Zinc Mine showed a decrease in zinc losses by the utilisation of Jameson Cell prefloat cleaner. Appraisal of a Jameson Cell in a scalping role within the Mt Isa Copper Concentrator indicated significant benefits could be achieved.

Jan 1, 2005

By G B. Smith, D Hillier, T Gibbons, D B. Donato, M D. Adams, S Davies, R S. Schulz

Responsible management of cyanide solutions and tailings on gold processing plants worldwide is an important aspect to these operations and is regulated via guidelines provided by the International Cyanide Management Code, an industry initiative designed to minimise cyanide risk to operators and the environment. Here we demonstrate the unprecedented causal relationships surrounding the saline (>14 000 mg/L total dissolved solids - TDS) and hypersaline (>50 000 mg/L TDS) cyanide solutions in gold plant tailings in the Central Goldfields of Western Australia, resulting in zero wildlife mortalities on three sites over the study period of almost one year. Wildlife interaction and ingestion is significantly lower than that experienced at other gold mine sites, with more rapid degradation of weak-acid dissociable (WAD) cyanide within the tailings storage facility (TSF). A rigorous chemical sampling using a novel æminimal accessÆ robotic sampler device and wildlife observation exercise was carried out at two hypersaline mine sites: Barrick Kanowna Belle (BKB) and Gold Fields St Ives (GSI) and one saline site, Barrick Granny Smith (BGS). The data was compared with available reported chemical sampling and wildlife observation data from a previously operational fresh water site (<2000 mg/L TDS) that had experienced wildlife mortalities, Case Study D (CSD). The comprehensive body of work, along with cyanide degradation test work carried out in the laboratory, was analysed via hypothesis development and testing, causation analysis and dynamic chemical modelling. The non-mortality effect on these sites appears to hold over a further four years of routine wildlife and cyanide monitoring by site personnel. This study has helped these three mine sites achieve and maintain full Compliance Cyanide Code status over a significant period while removing the need for operating the detoxification plants they would otherwise have required.CITATION:Adams, M D, Donato, D B, Schulz, R S, Smith, G B, Gibbons, T, Davies, S and Hillier, D, 2013. Hypersaline-induced reduction in cyanide ecotoxicity at gold operations, thereby obviating detoxification plants, in Proceedings World Gold 2013, pp 489-502 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

In order to fully understand why Amax Coal puts such extreme emphasis on the drilling and blasting programs at each of our mines, we must review the past. This paper will discuss the drilling and blasting techniques we used in the 1970s and their evolution to current practices. As time progressed, major changes influenced the surface mining of coal through new more restrictive governmental controls and local communities organising into groups with two goals in mind, one to shut down the mines and the second to try and get rich by making false and unjust damage suits against the mines. In virtually all of our midwest surface operations we have at one time or presently are facing litigation that has reached into the millions of dollars. Amax Coal has worked in co-operation with the United States Bureau of Mines in the areas of blast vibration, shot design, highwall safety, blast casting studies and many more. Today we are continuing to work with Dr David Siskind and his expert staff seeking answers to old and new problems addressing the blasting of overburden and parting seams.

Jan 1, 1995

By Kewu W

Kaolin used as an industrial mineral, especially that in the paper-manufacturing industry, must be of fine size, with high brightness, a low impurity content, and good crystal shape. However, in most kaolin deposits there are various impurities which have a very bad effect on the quality of the kaolin. Therefore, it is necessary to remove these impurities from kaolin ore. Owing to their similar surface properties, the separation of kaolin and iron oxide minerals, especially microkaolin and iron oxide minerals, has been regarded as difficult. The iron oxide minerals often intergrow with kaolin in fine and complicated forms, such as thin films, which make separation difficult. In order to overcome this difficulty, many workers have suggested various treatment methods and obtained great success. Based on research work by Fuerstenau (1980), Huang, Li and Hu (1984), Hui and Wei (1991), Shergold (1978), and Zambrana et al (1974), we have investigated a two-liquid flotation technique for iron removal from kaolin and obtained some success.

Jan 1, 1993

By P B. Hills

A simple algebraic method of aligning large scale underground excavations such as a crusher station or workshop or indeed any large cavern or mine layout to the optimal stress condition is outlined. The method uses the stress transformation law to determine how the component stresses vary as the stress tensor is rotated around its axis. The aim is to define the orientations at which the maximum and minimum horizontal stresses occur such that the excavation can be aligned with its long axis paralleling the trend of the maximum horizontal stress leading to the minimum potential for overstressing of the side walls. The physical environment in which the stress field is acting is unchanged. At the design location, the trend and plunge of the major principal stress is unchanged. However, the coordinate system by which the location of the stress field is described is arbitrary and the stress transformation law allows that coordinate system to be rotated to a more convenient orientation and for the component stresses to be calculated within the alterative coordinate system. The stress field is typically described in terms of normal and shear stresses aligned to a north–south, east–west, vertical, coordinate system. In this scenario, there are two orientations in the 360° horizontal plane defined by the coordinate system where the horizontal normal stresses are equal, and at 45° to those orientations, two orientations where they diverge to the maximum extent. Those orientations of maximum divergence correspond to the trend of the maximum and minimum horizontal stresses, usually designated σH and σh, and that is what the algebraic manipulation seeks to determine. This technique is a first pass assessment which relies on a knowledge of the full stress tensor. It is not a replacement for numerical modelling or detailed design, but a tool to guide planning.

Nov 29, 2022

As the worldÆs population and global standard of living increase, the role of metals in the economy will not diminish in the 21st century, despite substitution and dematerialisation trends. Industrial Ecology is an emerging science that attempts to bring together physical, biological and social scientists and develop the tools for good management of the planet in the long run. In engineering terms, Industrial Ecology is defined as the reconfiguring of industrial activities with full knowledge of their environmental consequences. Production and use of materials must take into account the needs of both market and environment. Dispersive uses of metals will be phased out, as is being done with lead in gasoline, and post-use recovery of materials and energy will increase. This will result in an advantage for metallurgical processes that can use as feed materials concentrates as well as metal scrap and waste streams, such as bath smelting processes and slag resistance electric furnaces. The paper also discusses how metal extraction technologies, developed in the 20th century to provide essential materials to humanity, can be applied for the benefit of both mankind and environment in the 21st century.

Jan 1, 2000

Continuous improvement in environmental management assists in the achievement of sustainability goals for the mining and processing of minerals. The use of regular internal environmental audits (scored or unscored) which form an integral component of an Environmental Management System (EMS), provide demonstrable evidence of this improvement. The audits described in this paper involve working with site personnel to develop and implement major improvement projects, providing advice on how to improve environmental practices and facilities, and disseminating innovative ideas and practices across the site and to other operations within the same group. Essentially the lead auditor assumes the role of a æskills coachÆ as opposed to a æpolicemanÆ, which is quite often the case for many audits. The audit process has been developed from involvement with a number of major coal mines in the Hunter Valley, where regular internal environmental audits have been undertaken every two to three months, over periods varying from 18 months to five years and more recently, with a metalliferous mine in the Northern Territory. Examples of the benefits of improved environmental performance (driven by the audit process) to sustainable development are provided. The auditing process as described is applicable to metalliferous mines, the processing of mineral ores, coal mines, coal handling and preparation plants, quarries, and oil and gas projects.

Jan 1, 2004

Alcoa of Australia's Del Park mining op eration is centred 9 km. east of the Pinjarra alumina refinery, and is centrally locatedwith- in the 10, 000 sq. km. lease which the Company holds for bauxite in the Darling Ranges. An- other mining operation is situated near the township of Jarrahdale, and supplies bauxite to the Kwinana refinery. Definition of the bauxite ore, development works and mining to the ore haulage stage, are identical for both mining operations. Exper- ience, and production cost figures, obtained from the Jarrahdale mine, where 100 tonne trucks are used to haul ore to a fixed crushing plant, led to the development of the Del Park mining concept with increased mobility of op- erations. The crushing-conveying-stockpiling arrangement at Del Park consists of a 1200 t. p. h. mobile crusher feeding bauxite to an overland conveyor system which transports the ore approximately 6. 66 km. to the stockpile area in the refinery. In the refinery raw mat- erials area the bauxite is distributed into 200, 000 tonne stockpiles by means of a travel- ling boom stacker.

Jan 1, 1973

The Japanese Government promulgated the æLaw Concerning Special Measures Against DioxinsÆ on 16 July 1999 and it was enforced on 15 January 2000. This is a unique law specialised to protect the environment by the control of dioxin emissions from waste incinerators and several industrial processes. In this law, a few metallurgical processes other than waste incinerators are designated as æspecified facilitiesÆ emitting certain dioxins. Thus, emission standards for dioxins to the air were set for electric arc furnaces (EAF) for steelmaking, iron ore sintering, zinc recovery from EAF dust and aluminum recycle processes. In this paper, the inventory of dioxin emissions for Japan and the recent research and development to reduce emissions from those processes are introduced. Further, some details on the formation mechanism of dioxins and future subjects for effective control of their emissions are discussed.

Jan 1, 2002