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Commissioning is one of the many phases of a project, it has inter-dependencies with the other phases, as they have amongst themselves, and has its own terminology and distinctive features. Commissioning time and cost can severely affect project economics, especially through unrealistic estimating, and requires a separate management team to ensure full control is. maintained. Targets to be achieved in commissioning are identified, together with the necessary policies to achieve them. Factors which have to be taken into account in applying these policies are Discussed.

Jan 1, 1986

By Conochie DS

SIROSMELT is a successful new pyrometallurgi- cal furnace system using a top-entry lance which can be submerged in both slag and matte. The lance is of simple construction, and is cooled by process air. Pilot plant work commenced in the CSIRO Division of Chemical Engineering in 1972 using a 50 kg batch reactor. This paper traces the development of the technology through various slag cleaning and smelting processes up to a scale of 5 tonnes per hour continuous feed. Strong co- operation between CSIRO and the Australian smelting industry has contributed greatly to the success of SIROSMELT.

Jan 1, 1984

By B Oostendorp, R van der Merwe, P

In order to assess whether polysaccharide depressants are strongly or weakly and reversibly bound to the surface of talc, a series of experiments was conducted on New York talc in which the floatability of the talc in a microflotation cell was determined. The talc was conditioned in solutions of carboxymethyl cellulose (CMC) or guar gum in 10-2 ionic strength Ca(NO3)2 or Mg(NO3)2. The talc was then washed with four successive aliquots of water, or cation solution, to try to remove the polymer and the flotation response of the talc was assessed. CMCs of different charge (DS) were used to assess the effect of charge on the strength of bonding. The results show that CMC and guar gum could be removed to a large extent from the talc surface by washing with water (the floatability was restored), however very little could be removed from the surface by washing with cation solution. The higher charge CMC was easier to remove from the talc planes in the absence of cations than the lower charge CMC. Thus CMC bonding to talc has been shown to be irreversible or very slowly reversible only if cations are present, implying that cations are necessary to keep the polymer bound to the surface of the planes to effect depression. The presence of ions in solution also had the effect of maintaining surface coverage of the talc by guar gum.

Jan 1, 2005

By D Craw

Interactions between structure and lithology in the Hyde-Macraes Shear Zone controlled the style of gold mineralisation at the Macraes mine. Large volumes of rock in some mine pits have most gold disseminated in hydrothermally altered schist, rather than in quartz veins. Mineralisation was initiated in the latter stages of metamorphism. Pods of massive schist rich in quartz and feldspar are surrounded by more fissile schist consisting of interlayered micaceous and quartzofeldspathic schist. Later shears have been partly controlled by the micaceous schist, and anastomose around pods of more massive schist. Micaceous schist was replaced by pyrite and arsenopyrite, accompanied by recrystallisation of phengitic muscovite under lower greenschist facies conditions. Gold occurs in sulfides and with microcrystalline quartz formed during minor silicification. Massive schist is locally mineralised along sulfidic microshears which have phengitic muscovite largely illitised under sub-greenschist facies conditions. Mineralised massive and micaceous schists were overprinted by cataclastic shears, with addition of graphite and more sulfides. Mineralisation occurred during a transition from ductile to brittle deformation regimes as the schist was uplifted in the late Jurassic.

Jan 1, 2004

By Espinosa-Gomez R, Johnson NW

The Copper Concentrator at Mount Isa Mines Limited treats on average 18 000 tonnes/day of chalcopyrite ore containing typically three per cent copper. The main gangue minerals are iron sulphides (-13 per cent) and non sulphide gangue (-78 per cent). In August, 1991, the comminution flowsheet was changed from a conventional circuit (crusher/rod mill/two stage ball milling) to a modem circuit (fully autogenous grinding/one stage ball milling). The 80 per cent passing size of the flotation feed with the conventional circuit was 125 microns. The Copper Concentrator has two parallel grinding lines, two roughing and scavenging flotation lines, and common cleaning, recleaning and retreatment sections. During the first six weeks of the installation phase, one of the two flotation lines was fed by the conventional grinding circuit and the other by the autogenous grinding circuit. Data from parallel surveys and historical data are used to analyse the rougher/scavenger flotation performance before and after the change. The solid and mineral distributions of the flotation feed, the pulp chemistry and the reagent requirements are compared. The mineral liberation before and after the installation of autogenous grinding is compared on a sized basis using data from the 14 consecutive months before, and the seven months after the change. Liberation was measured using the QEM*SEM(*) instrument. The overall effect of the new grinding circuit on the plant metallurgy is also assessed using the copper recovery values, the dilution of the final concentrate and the distribution of copper losses in the final tailings. (*) Quantitative Evaluation of Materials by Scanning Electron Microscopy

Jan 1, 1993

The design and construction of a 2.5 million tonne per annum ship unloading system at the PWCS export coal terminal in Newcastle, NSW, has further increased the flexibility and sophistication of Australia's largest coal export facility. The system comprises a new unloading wharf serviced by a self unloading vessel, conveyor stream and multi compartment ground level storage shed. Coal is reclaimed from this shed by the largest portal scraper ever installed under cover. The system also provides additional flexibility by receiving coal from the existing PWCS road receival to improve scheduling. The PWCS can now simultaneously handle 11 coal types and receive from rail, road and sea at almost 15000 tonnes per hour.

Jan 1, 1987

Optimisation of capital in the development process is critical to the profitability of any new mining venture. The process of optimisation should apply to all aspects, that is the financing, management, revenue, reporting and, of course, the development of the project. Unfortunately, too much emphasis has been placed on the optimisation of the financing or reporting aspects and too little on the project itself. This paper addresses the latter.

Jan 1, 1991

By J Rostami, D Tadic

While hard rock tunnel boring machines (TBMs) have an established track record in the tunnelling industry, accurate estimation of TBM performance for each specific project remains critical. Machine performance prediction is required to assist planning activities, including costing and schedule preparation, machine specification and effective planning of maintenance and repairs. In addition, monitoring machine performance during the construction period is required to assess and manage excavation progress, and to achieve optimal advance rates based on specific geotechnical conditions exposed during excavation. TBM performance analysis can also contribute to the development of more accurate performance prediction models for future applications. Rock mass characteristics play a dominant role in machine performance. This paper offers a review of the impact of rock mass characteristics on TBM penetration rates for two specific tunnelling projects. A discussion is provided on the results of statistical analysis of available field data, including geological back mapping, rock properties and measured rates of penetration (ROP). The analysis offers a comparison of the achieved and predicted ROPs to provide a better understanding of the influence of rock mass properties on the performance of hard rock TBMs. A new rock mass adjustment factor is introduced to enhance the accuracy of an existing prognosis model for use in jointed rock masses.

Jan 1, 2008

Environmental leaching methods such as the toxicity characteristic leaching procedure (TCLP) test or the ASLP test are used to assess wastes including mining and mineral processing by-products. These tests were initially designed as regulatory tests simulating conditions in a co-disposal municipal landfill waste facility and do not allow leaching performance to be predicted in site specific scenarios. Further, the assumptions underlying these tests tend to define worst-case scenario leaching conditions for by-products from the mineral industry disposed of outside a co-disposal scenario.   Recently some characterisation leaching test methods have been issued as ISO/TS standards (ISO/TS 21268-3:2007 and ISO/TS 21268-4:2007) that aim to define the leaching performance of soil type wastes and to predict the leaching performance of these wastes over long time frames. In this preliminary work these standards are trialled for by-products from the mineral industry and the quality of information that can be obtained from them compared to TCLP/ASLP tests.   Where clear comparisons were possible, the TCLP/ASLP tests were typically found to extract a similar, or often greater, amount of component than (i) tests conducted at the same pH but without the acetate buffer or (ii) for test conditions aimed at simulating long-term leaching in an eluate defined by the waste type. While further work is required, the preliminary results indicated that the tests may provide reliable long-term estimates of leaching performance of wastes in soil types of variable pH and provide a suitable basis for long-term planning for optimal waste handling, treatment or even re-use.

Jun 1, 2010

By S Saydam

Professional engineers need to be able to apply university learning to practice. In particular, they have to take responsibility for interactions between technical systems and the complex social environments in which they operate. The most effective way of building this competency is through active experiential learning. We have been developing an advanced educational integrated simulation system to provide mining engineering students with an interactive and immersive learning experience that is not otherwise possible. This will give students an authentic experience in working with industry software packages, while also contextualising the learning in terms of the broader and longer-term impact of technical decisions. We have been piloting the system, in undergraduate courses in order to establish its effectiveness in building systems thinking competencies for mining engineering. For postgraduate students and professionals, the same tools and methods can support studies of more challenging and complex scenarios where mining engineers have to place their decisions within complex global industry contexts.

Nov 22, 2011

By C A. Fleming, C J. Ferron, P T. OÆ

A new process is described which allows for direct recovery of base and precious metals (Au and PGMÆs) from sulphide concentrates or other feedstocks. The process was developed initially for application to ores or concentrates that are too low-grade for economic treatment by the conventional smelting and matte leaching process (for PGMÆs). It is now believed that the process may be widely applicable to a variety of materials including PGM concentrates containing high amounts of chromium or magnesium. Operating conditions have been identified under which gold, the PGMÆs and the base metals dissolve simultaneously in a pressure leaching autoclave. The product of this leaching process can then be treated by one of several flowsheets, of which the preferred will likely involve solid/liquid separation, followed by precipitation (or adsorption on activated carbon) of gold and the PGMÆs, followed by copper solvent extraction/electrowinning. Depending on the concentrations of nickel and cobalt, the copper raffinate would either be partially recycled to the autoclave to allow Ni/Co concentrations to build up, or it would proceed directly to a Ni/Co refinery. This paper deals with the pressure leaching process and the recovery of gold and the PGMÆs from the pressure leach product.

Jan 1, 2000

By Johns D. R

The producers of mineral sands on the East Coast of Australia might be regarded as having a simple task of selling Rutile and Zircon. Such is not the case. Differing quality and grain size requirements plus the dramatic increase in the percentage of mineral sold in a processed form have meant a large increase in the number of different end products handled. The resulting sales control problems are compounded by the need to be able to deliver against a large number of separate contracts which may relate to spot or long term sales in small quantities or in bulk shipments. Methods of helping management control this situation have been devised and incorporated into a suite of computer programs. Experience with the approach has been very satisfactory. The effect of changes to shipping schedules, commitment to new or changed orders, or proposed changes to production can be evaluated as and when necessary with little bother. Confidence in decisions taken is high since the process of data collection has been designed to involve

Jan 1, 1977

This paper traces briefly the reasoning which led to the decision to extend the existing internal shaft at the Rosebery Mine and to instal underground a larger winder (No. 2 Hoist) with capacity to handle all hoisting requirements to a depth of approximately 2,500 ft. on an incline varying from 83" to 55" to the horizontal. It then covers the specifications and selection of the winder, the design of the winch chamber, rope raise and bins, the excavation, support and lining of the chambers and the transport to site and installation of the machinery. Finally a brief description is given of the mechanical and electrical parts of the winder.INTRODUCTIONThe existing shaft winder on the internal inclined shaft situated on No. 8 Level of the Rosebery Mine had reached the limit of its capacity. Hoisting 21-ton capacity skips in balance, with a 13/16-in. diameter rope, it required four layers of rope on the 3 ft. 6 in.drums to reach the loading station under No. 12 level at a depth of 864 ft. (Fig. 1). This entailed heavy wear on the multi-layered rope and heavy stresses on the cheeks of the drums. Continuous working on three shifts was necessary to handle ore, men and materials, and a hold-up from any cause whatever meant an interruption to production on the lower levels of the mine. The maximum output of the hoist whilst hoisting from the No. 12 level loading station was 50 tons per hour. It was obvious therefore, that a larger winder was required if output was to be maintained.Diamond drilling had proved the existence of sufficient ore at depths well below No. 12 to warrant exploitation and a decision had to be reached on the means of hoisting this ore.

Jan 1, 1958

Research and Technical Services, Department of Mines Western Australia The nine papers received for this technical session cover a very wide range of hydrological problems in various parts of the world. Three of these papers deal with hydrological predictions for new mines, while three are concerned with the prediction of water chemistry. The three remaining papers deal with gas injection as a dewatering tool, discharge formulae verification and the use of a physical model to predict subsurface strata movement and fracture development due to longwall mining. Hydrological problems in mine planning represent a major risk in many mining operations, booth as a potential life or equipment hazard and a major financial risk. The initial paper selected to review was therefore one by the president of a gold mining company, rather than by one of the specialist scientists, to remind us all that the main reason problems are faced and overcome in the mining industry is usually a commercial one. In one commercial undertaking, the ability to accurately assess future risk is a highly desirable planning tool and hence in mining, the ability to predict the nature and magnitude of hydrological problems is n i-an varxi imnnrfant

Jan 1, 1988

By Perring CS, Barnes SJ

The nickel exploration boom of the late-1960s and early-1970s led to the discovery of numerous komatiite-hosted nickel sulphide deposits, associated with variably serpentinised bodies of olivine-rich cumulates. Subsequent research has shown the importance of volcanological processes to understanding the genesis of these deposits. Crucial developments have come through consideration of the fluid dynamics of magmas and magma-crystal mixtures, through observation of the dynamics and geometry of modern day basaltic lava flows, through application of theory and experimentation on the kinetics of crystal growth from magmas, and most importantly from extensive detailed field mapping of komatiitic sequences in the Yilgarn Block and elsewhere. From these studies has emerged a new integrated view of the volcanological setting of komatiite-hosted deposits, and a recognition that a complete continuum of deposit types exists. Nevertheless, komatiite associated magmatic nickel deposits generally fall into two overall types based on the nature of the sulphide ore. In the first type the bulk of the ore is either massive Fe-Ni-Cu sulphide or a variable mixture of massive sulphide and an ore characterised by olivine crystals in a continuous matrix of sulphide occupying between 30 and 75 per cent by volume of the rock (called Matrix Ore). Nickel grades of massive sulphide ore range from 2 - 20 wt% and those of the matrix ore generally fall in the range 1 - 5 wt% (average 2.5 wt%) Ni/Cu ratios of the sulphide fraction are generally >10.

Jan 1, 1996

Hamersley Iron Pty. Limited mines and pro cesses iron ore from two orebodies at Tom Price and Paraburdoo, situated in the North West of Western Australia. Conventional open pit mining methods are used at both sites in that material is drilled and blasted in benches, loaded by shovels and hauled to the Primary Crushers or dumped on waste or low grade material stockpiles. The present drilling fleet, consisting of eight high capacity Bucyrus Erie Rotary drills has evolved from an initial fleet of a large number of small percussion rigs. There are significant physical differences between the ore types encountered at both mines which nec- essitate the drilling of smaller diameter blast holes at Paraburdoo than those at Tom Price. The drilling practice at each site is dis- cussed, with examples of performance achieve- ments under varying drilling conditions.

Jan 1, 1978

Extensive geophysical exploration and drilling operations have been: conducted in, South Central Queensland by Phillips Petroleum Company and Sunray DX Oil Company since late 1959. The main outlines of subsurface geology are now known, but many problems must be solved before a comprehen sine. picture can be presented of the geology and petroleum prospects e Interpretations to date suggest that -fiddle Paleozoic sedimentary rocks, probably, related to the Tasman belt of geosynclines, once extended. over. most. of the area An oro;eny 2.n late Paleozoic time, succeeded by deep pre-Pexmian erosion, removed the older sediments over large. areas, but Paleozoic sediments, were preserved from erosion in the Adavale and ancillary structur-a.l basins. Marine sediments of Devonian age are con-sidered prospective source beds for petroleum. Current work is directed toward finding favorable structure and reservoir beds to test the oil prospects of the area.

Jan 1, 1962

By Gregg PEH, Stewart RB

Reclamation field trials commenced in 1985, two years before the granting of the Mining Licence. The level of pasture production on varying soil depths (0 cm, 5 cm, 15 cm and 25 cm) overlying both tailings and oxidised waste overburden was assessed. After seven years, the rate of increase of N, C, P and S, losses of S and P and pH changes were investigated on the plots where grass seed was sown into bare tailings. It was determined that on these plots it would take approximately 24 years to reach the original carbon and nitrogen levels at the mine site.

Jan 1, 1995

The Department of Mineral Resources is the lead agency in mine site environment management and control in New South Wales. The Department introduced a Mining, Rehabilitation and Environmental Management Plan (MREMP) process several years ago in order to integrate the activities of other government agencies who may have a material interest at the mine site. The MREMP process has resulted in a spirit of trust and co-operation between agencies and between agencies and mining companies. The spirit of co-operation has been reflected in greater public confidence that mining is environmentally responsible.

Jan 1, 1995

By C Slaughter, J C. Tien

Commonly held ideas about effective training have long emphasised the importance of realism. Realistic training builds better experience among the trainees and a better perspective on the training material, making training more effective. While great strides have been made in this realm for mine safety and mine rescue training there are still areas that can be improved. One possible area is the expanded use of a mine fire simulation program where the migration of gases and smoke can be realistically displayed in an emergency, and outcomes varied as different conditions are being simulated. The use of mine fire simulation software potentially allows for the creation of more realistic scenarios in that smoke advance rates can be measured and recreated in evacuation scenarios, or that gas readings in mine rescue training can be dynamically and realistically changed to show the effect that time has on the fire scenario.CITATION:Slaughter, C and Tien, J C, 2015. The potential use of mine fire simulation software as an enhancement for mine safety and mine rescue training, in Proceedings The Australian Mine Ventilation Conference, pp 285–290 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015