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The short review of hydrogeologic conditions in the three Polish coal basins have been presented as the background for the prevention measures against water inrushes being underta- ken in coal mines. The Polish mine safety regulations concerning water inrush prevention have been discussed, namely: - classification of sources of the potential water inrushes, - levels of water inrush risk and conditions of mining operation in the mines facing particular risk levels, - determination of the -di.mens.ons.of protecting pillars to prevent water inrush to mines, protection of surface water reservoirs and their earth embankments in regions submitted to mining deformations. Three examples of coal mining being carried out under water bodies have been presented.

Jan 1, 1988

Many aspects of best practice resource evaluation do not create value, but poor practice can certainly destroy value. Generally companies prefer to present how their good practice adds value and for this reason few publications exist on examples of how poor practice can destroy value. However in big and small companies there are many previous and current examples of poor practice destroying value. The incremental expenditure required to move from poor practice towards best practice can be looked upon as insurance against destroying shareholder value. Examples of how poor practice in geology has destroyed value are presented as well as the improvement model used by BHP Billiton to add value and insure against destroying value.

Jan 1, 2002

Hilton Mine is located 20 km north of the city of Mount Isa and Isa Mine in far north west Queensland. The sealed road used by the 500 employees to commute from the city is part of the Barkly Highway linking Mt Isa to the Northern Territory.Although discovered in 1947, major underground development did not start until late-1982 and first cut-and-fill production in mid-1987. The J53 exploration shaft was sunk in 1970-73 and the main P49 shaft in 1973-75. Since January 1990, most of Hilton ore production has been treated in the Hilton Concentrator, and concentrates trucked in slurry tankers to Isa for smelting or shipping.

Jan 1, 1993

The curbing of expansion in tertiary level education in Australia and the question- ing of its objectives which are now occurring are likely to have important effects on mining and metallurgical education. Student enrol- ments are low but the serious shortage of specialised minerals industry graduates pre- dicted during the boom of the late 60's has not eventuated. Other manning problems of a less quantitative but possibly equally import- ant kind have been identified. They point to a need for a full and deep review of the education and training programmes available to Australian graduates planning to enter product- ion areas of the minerals industry. An alter- native educational structure providing greater flexibility is suggested.

Jan 1, 1977

Mary Kathleen Uranium Ltd. recommenced operations in early 1976 following a twelve year period of care and maintenance. Several sections of the plant were modified or completely changed for the second operation. The most important change was the replacement of ion exchange with solvent extraction as the means of purifying and upgrading uranium rich Isolutions Most of the problems experienced in the solvent extraction system originate from the leach liquor which has a strong tendency to form stable emulsions. This has been countered by some careful control of leaching conditions and by closer observation of operations in the solvent extraction area. Most problems have now been resolved and plant recoveries are quite Satisfactory.

Jan 1, 1978

By Grace NC, Lightfoot BW

Small scale trials of the smelting of a copper concentrate in the Sirosmelt submerged lance reactor are described. Pellets of concentrate were dropped into the reactor while injecting air-rich mixtures of oil and air through a lance into a bath of matte overlain by slag. This produced a discardable slag and a matte which was converted in sequential stages in the same reactor to white metal and blister copper. Difficulties were encountered in determining the end points of the converting stages but control techniques were developed to allow successful operations producing blister copper. Deportments of minor constituents of the concentrate to slag, matte,metal and fume for the three stages are reported and possible applications are Discussed.

Jan 1, 1980

By S N. Nyoni, K C. Corin, C T. O’Connor

Considering future water scenarios, as influenced by the increasing scarcity of water and the move towards sustainable process engineering etc, the closed water circuit becomes an important point of study in metallurgical operations, such as in milling and flotation. However, a deterrent in the use of recycled process water is often a lack of understanding of the effects of the accumulation of dissolved ions and other process chemicals. Recovery of the valuable minerals may be impacted by the concomitant complex mineral-pulp chemistry interactions. Literature indicates that these interactions are not necessarily antagonistic to process outcomes. Wet milling using steel media results in the dissolution of Fe from the media, the rate of which is dependent, inter alia, on the type of media and the chemical conditions of the aqueous environment in the mill. The pulp-phase interactions of dissolved ions with sulfide minerals may result in significant changes to the chemical conditions in the mill, which may subsequently impact negatively on the flotation recoveries. To understand the effect of these interactions in the context of the processing of sulfide minerals, this study seeks to consider the effect of three factors, viz mineral type – pyrite (Py) and galena (Gn) -, milling media of different compositions – forged steel (FS), 21 per cent high chrome and ceramic media -, and water chemistry, viz, deionised water (DI) and synthetic plant water (SPW). Ceramic media and galena are used for the respective control cases where the milling media and sulfide mineral contribute no Fe species. Using DI as a control case, a high ionic strength case is used to mimic the changes in water chemistry for a closed water circuit. Batch flotation tests are used as a diagnostic tool to determine the effects of these media-water-mineral interactions to investigate correlations between the chemical reactions occurring and chemical species present during the milling process and the ultimate flotation performance.

Aug 24, 2022

By P Cameron

Many products and technologies have been developed from outcomes of research projects carried out by the Julius Kruttschnitt Mineral Research Centre (JKMRC). When these products and technologies are applied to the design and optimisation of blasting, comminution and separation, improvements in profitability can be realised. In 1970 Alban Lynch promoted two practical ideas to improve plant operations: Ore and equipment properties can be separated allowing experience with one type of ore or equipment to be transferred to other types of ore and equipment. If this experience was encapsulated in a mathematical model, then these properties could be combined and used to simulate (ie to design and to optimise) complete mineral processing circuits. Many problems associated with scale-up from laboratory to industrial equipment could be eliminated by experimental work on full-scale equipment in the plant. Many JKMRC research projects have focussed on the development of models of unit operations in mineral processing and their application to process simulation. Models of comminution and classification developed at the JKMRC have been used since the early-1980s. Ore characterisation techniques developed to support these models are licensed world wide through JKTech. The application of comminution modelling techniques to blasting, which optimises the process feed size distribution is used in Mine-to-Mill? projects. The advances in the understanding and modelling of froth flotation over recent years have provided the opportunity for integrated ore characterisation and process optimisation from resource to product. JKMRC project outcomes often provide proven opportunities for the mineral industry to improve performance and productivity. JKTech was established in 1986 to commercialise and market the most promising outcomes and thus ensure their continuing availability to the mineral industry. These include: commercial software (JKSimMet, JKSimBlast and JKMetAccount); monographs (Comminution and Blasting); technologies (Mine-to-Mill? and flotation optimisation); and hardware products (JKFrothCam, JKJetLift? and the Mineral Liberation Analyser). This paper summarises these technologies and their benefits.

Jan 1, 2002

The Callie Underground Mine is located in the Tanami Desert 560 km Northwest of Alice Springs in the Northern Territory and is currently operated by Newmont Australia Limited with all mining activities carried out by Henry Walker Eltin. Callie was discovered in the region in 1991 with the box cut portal commenced south of the pit in 1995 and underground ore production commenced in 1998, after completion of the profitable Callie Open Pit. Development is currently occurring at depths of over 700 m with the decline currently below the 640 Reduced Level (RL) level (surface RL of 1400) with production haulage from 600 m below the surface. The combination of auto compression, a moderate geothermal gradient of 2¦C/100 m and diesel heat transfer causes the wet bulb temperature of intake air at the bottom of the mine to be typically 5¦C higher than on the surface. Wet Bulb temperatures can be up 5¦C higher again in active areas under secondary ventilation. During the 2002/2003 wet season many activities in the lower levels of the mine were stopped due to miners experiencing adverse heat related symptoms or the temperatures exceeding the Underground Heat Management Procedure stop job criteria of 32¦C wet bulb. To improve the working environment, combat the heat related illness and improve operational efficiency, a temporary 1.8 MW refrigerated cooling plant consisting of three 600 kW modules were installed underground to provide bulk air cooling for the lower levels of the mine during the 2003/2004 wet season. Several studies have been conducted in relation to future ventilation demands at Callie and all came to the conclusion, that some mine cooling will be necessary for Callie to meet the high production and development demands. This paper will describe the ventilation network at the Callie Underground operation focusing on the installation, operation and effectiveness of the temporary underground refrigeration plant.

Jan 1, 2005

By Li G, Dean-Jones G. L, She T

Highwall mining is a specialised and largely automated mining method developed in the United States for the extraction of coal left under a shallow overburden cover after cessation of economical open cut mining operations. As the name indicates, coal is extracted from the seam exposed along a highwall by a remotely controlled continuous miner operating in a single unsupported opening and brought to the surface by a string of conveyor segments. The single entries are separated by coal .pillars and driven normal to the highwall, over areas where the thickness of cover and volume of recoverable coal is insufficient to allow or justify conventional underground mining. An additional highwall mining method is augering. The success of high wall mining operations depends significantly on geological features, notably the stability of the working roof, determined by the type and mechanical properties of the immediate roof strata. Stability of the ribs, absence of floor heave, faults and dykes are further important prerequisites for profitable highwall mining. The geometric relationship between the spatial attitudes of existing joint systems, the direction (azimuth) of the single entry opening and its vertical profile determine the unimpeded depth of penetration into the coal and thus its economic success. The mechanical implications of the lithological transition zone from a coal seam to either primary or original roof strata, compared to an interface between the coal seam and overlying strata, characterised by a sharp erosional boundary between coal and a secondary immediate roof stratum, are very significant. The compatibility between the response to mining by the geological system (floor-seam-roof) and the capability of the mining equipment to prevent the development of instability are essential requirements from a mechanical viewpoint. The minimisation of vibrations, very good horizon control, an ability to vary the profile of the opening, and the maintenance of consistently high advance and retreat rates, are also important aspects of profitable highwall mining.

Jan 1, 1995

Kumba Iron OreÆs Sishen Mine is one of the worldÆs largest iron ore mining operations situated in the Northern Cape, South Africa. It produces 29 million tonnes of iron ore products per annum using a dense medium separation (DMS) beneficiation process. Kumba is currently commissioning the Sishen Expansion Project (SEP) which will produce a further 13 Mtpa product through a jigging beneficiation process. The products from the Sishen Mine are highly sought after and consumed by domestic and various European and Asian customers. During beneficiation iron ore slimes are generated and discarded as waste material to the slimes dams. A study was initiated in 2005 to investigate processes to beneficiate these slimes to saleable products û prompted by the current high demand for iron ore products and the high grade in the Sishen slimes thickener underflow of approximately 54 per cent Fe. Initial laboratory scale test work indicated that a 66.5 per cent Fe iron ore concentrate could be produced from the Sishen slimes thickener underflow through a process of classification, two stage wet high intensity magnetic separation (WHIMS) and five stage flotation. This process, however, did not produce the desired results during pilot plant testing and numerous alternative process routes were investigated. The process that did achieve the desired product grade of 66.5 per cent Fe at economically feasible product yields consisted of two stage WHIMS using SLON magnetic separators. Results achieved indicate that the thickener underflow slimes can be upgraded from 54 per cent Fe to 66.5 per cent Fe at a product yield of ca. 40 per cent. Product yield could be increased through the further beneficiation of the SLON tails. The Sishen slimes thickener underflow production rate is ca. 3 Mtpa û resulting in a potential concentrate production of ca. 1.2 Mtpa. The slimes concentrate will be fed to a pelletising plant that will produce 66 per cent Fe pellets destined for domestic and or export markets.

Jan 1, 2008

The impact of computers on the mining industry has increased for the past twenty years in most parts of the world. The application of computers in the mining industry has been demonstrated in areas such as geological data analysis, ore reserve estimation, mine planning, and manpower training. There is also a general concern in this country regarding the computing background of graduating mining engineers from the Australian higher institutions of learning. This paper describes specific steps which have been taken at the Department of Civil and Mining Engineering, The University of Wollongong to provide adequate computing background to mining engineering graduates. Specific topics discussed include hardware and software available to students and how "computers" have been integrated into the mining engineering course.

Jan 1, 1986

By Q Xin, X Shengming, C RuÆan, Z Zhigeng a

The optimum defluorinating conditions for Sichuan bastnasite crude ore were determined by orthogonal experiments. Over 95 per cent fluorine in the crude ore was stripped by roasting 30 minutes of the crude ore with Na2CO3/ore =0.25 at 650oC. The stripped fluorine crude ore was further treated by NH4 Cl to recover rare earth. Above 95 per cent rare earth can be leached by water after the stripped fluorine crude ore mixed NH4Cl(NH4Cl/ore =1:1) roasted 1 h at 325oC. At the same time, the rare earth leaching solution contains little Fe, Si and Al. Therefore it is propitious to further purify the solution and recover rare earth.

Jan 1, 2000

Poorly designed sampling protocols generally result in high project risk by artificially increasing grade variability (ie the nugget effect). Sample collection, preparation and assay protocols that suit the ore type, together with QA/QC systems, will reduce this risk. All reporting codes (eg JORC, 2004) require the Competent Person to consider the quality and implication of sampling and assaying programs. High sampling errors beget higher project uncertainty; despite this fact, sampling does not receive the attention it deserves. The case studies presented show that many sampling issues frequently go unrecognised or unaddressed, resulting in poor project decisions during exploration through to feasibility and production. The overall conclusion is that correct sampling is critical to mining project success and that there is often a need for its optimisation.

Jan 1, 2007

Comalco Aluminium Limited uses a computer system for cost, supply and maintenance reporting and control at its bauxite mine in Weipa, North Queensland. The system collects data on a daily basis at a high level of detail on both cost and maintenance history. This allows useful reporting to all levels of management from the shop floor to the General Manager. The most successful aspect of the system is that the information is available in all workshops on visual display units. This allows the real spenders of the Company's money, Foremen and Tradesmen, to make well informed decisions. The system has also decreased the time taken to find parts and information which gives the Foremana greater opportunity to do his real job of supervision and quality control.

Jan 1, 1983

By Warren R. P

When the original Mount Gunson joint venture, between CSR and United Uranium ceased operations in December 1971, an intensive ex- ploration campaign was launched to prospect for more ore in the Mount Gunson region. This campaign resulted in the discovery of the Cattle Grid deposit. A comprehensive sampling programme proved the existence of 4.6 million tonnes of ore, at a mean grade of 2.4% Cu, calculated at a 1.0% Cu cut-off. The planning and development programme that followed this discovery included not only the mining and metallurgical aspects of the exploration of the deposit, but also the en- vironmental aspects. Preliminary work included data collection with respect to meteorology, soil types, and existing flora and fauna.

Jan 1, 1976

By Jaczkowski B. M, Cox T. J, Domfeh I. A, Stalker I

Mining and treatment of gold ore in the Ashanti region at Obuasi, Ghana has been continuous for more than 100 years. Earlier production from this world class deposit can be traced far into the history of West Africa's gold trade. As part of a general development and expansion program, Ashanti Goldfields Corporation (Ghana) recently undertook a program to heap leach oxidized near surface ore. Kappes, Cassiday & Associates was given a major role in the design, equipment supply, installation and start-up management of the 3000 tonne/day heap leach. Unusual conditions included a high annual rainfall and an ore which could be characterized as a soft, decomposed, water saturated schist. Production began in March 1990. Startup problems and their solutions are discussed.

Jan 1, 1991

By A C. Robertson

Over the past decade there has been continual change in the way that mines have been managed and the component roles of those people who make up the total mine management system. Major issues have included the change in the business structure of mining companies, the change in on-site infrastructure, increased personal liability of managers for the safety and health of employees and increasing social and environmental pressures on managers and their staff. This paper looks at the changing roles of two of the many groups of professionals associated with the mining industry - the equipment supplier and the mining consultant. The profiles of the ACME Group Pty Ltd, suppliers of ventilation equipment and ancillary canvas and plastic products to the mining and construction industry, and Tennent, Isokangas Pty Ltd, Consulting Mining Engineers, are presented.

Jan 1, 1998

By A Radici, S Russell

The Dampier Port Upgrade was completed in 2007 and is the largest project in Rio Tinto Iron Ore's expansion program. The project doubled Dampier Port's iron ore shipping capacity over a five year period. Sinclair Knight Merz (SKM) was appointed by Rio Tinto as the Engineering, Procurement and Construction Management (EPCM) contractor to manage Phase A and Phase B of the Dampier Port Upgrade. The aim of the project was to increase the Dampier Port capacity from 74 to 140 million tonnes per annum (Mt/a). This increase in shipping capacity tripled the capacity of the Parker Point facility from 34 to 94 Mt/a, whilst the East Intercourse Island facility increased from 40 to 46 Mt/a. The Dampier port remained fully operational throughout construction and achieved record yearly export tonnages over the period of the project. The $US1.4B project was completed ahead of schedule, on budget and with an outstanding safety record. Significantly the project team set an industry benchmark by achieving five million man-hours Lost Time Injury (LTI) free. The project has been recognised by the Engineers Australia 2008 Western Australian Engineering Excellence awards as category winner in resources and the overall winner in WA, and went on to win a National Engineering Excellence award. This paper provides an overview of the EPCM project management and an insight into some of the key drivers that have delivered this outstanding project.

Jan 1, 2009

A useful sampling device can be constructed using three movable flaps. One is moved between its two extreme positions as material is flowing past it; the other two are only moved while no material is flowing past them. Material commences to flow into a sample container as the primary flap is moved from right to left, continues to flow into the sample container as the primary flap is moved from left to right, and the flow is terminated as the primary flap is next moved from right to left. As for several other sampling devices, an argument that there is no delimitation error can be made on the basis that the sampler conceptually divides the stream up into discrete portions and takes a set of equally-spaced portions as a sample.

Jan 1, 2008