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I have been asked to speak today on the topic of Project Finance in the Mining Industry. Through this presentation, I hope to give you a broad outline of the concept of project finance. The first half of the presentation covers the principles involved in project finance and the second half moves to aspects more specific to the mining industry. I have worked for 3 years at Rothschild Australia. Rothschild provide finance for projects in the mining industry, world wide. We finance both large and small projects, with facilities varying from $2m to $100m.

Jan 1, 1990

One of primary causes of poor blast performance is the improper relief of explosive energy. Under or over-confined blasts modify the explosiveÆs path of least resistance, which changes where and when the explosive energy is applied resulting in less than optimum blast performance. During the research for this paper the overbreak characteristics of five full-scale blasts were quantified using high speed cinematography and borehole cameras. The effectiveness of various overbreak control methods was also evaluated to guide design refinement. The results of this research along with general recommendations for reducing excessive damage are included with this paper.

Jan 1, 1999

The major incentives for developing continuous processes for the production of formcoke are to achieve a wider range of coals which can be used, greater operating flexibility enabling the production of various coke qualities, and environmental improvements. The characteristics of a formcoke which must be considered when assessing its performance in the blast furnace are compressive strength, abrasion resistance, volatile matter, reac- tivity, porosity, density, size, shape, ash yield and sulphur content. Lurgi's development work in attempting to pro- duce a formcoke which meets the specified requirements has resulted in most current efforts being concentrated on the Bergbauforschung/Lurgi hot briquetting process. This process blends hot char produced from a non-caking coal with small quantities of caking coal in a special mixer in the plastic range of the caking coal. The material is subsequently briquetted hot, then subjected to a thermal after-treatment to produce a strong abrasion resistant formcoke. A 650 tonne per day plant for British Steel Corporation is now under construction. A study of the equipment requirements and the operating costs indicate that the economics of large scale formcoke plants compare favourably with those of conventional coke-making plants.

Jan 1, 1975

By Ritchie IC

Spiral separators have been used to treat heavy mineral sands in Australia for some thirty-five years. They were used as the primary treatment method until the advent of the Reichert cone, which largely replaced them, due to its compact design and relative ease of operation. Spirals continued-to be used as the final cleaning stage before dry separation of the heavy minerals as they remained the most efficient separator for this purpose.

Jan 1, 1986

By C R. Sundberg

Despite nearly a half-century of continuous production, the low-grade iron ore (taconite) deposits of North America remain economically competitive sources of raw materials for the domestic steel industry. The continued viability of these mature integrated mining-concentrationagglomeration complexes requires highly efficient utilisation of assets, especially the mineral resource. At Cleveland-CliffsÆ five North American managed operations, enhanced ore characterisation techniques are playing a critical role in their continued success. Due to the low-grade nature and complex mineralogical composition of these deposits, ore characterisation cannot solely rely on assay grades. Historically, taconite ore characterisation has augmented assay grades with bench-scale concentration tests to quantify recoverable mineral. The economic necessity for improvements in mill efficiencies and final product quality has mandated significantly greater knowledge of ore-related impacts. Cliffs Technology Center has met this challenge by developing a variety of novel iron ore characterisation techniques. The applications developed include both in situ and laboratory procedures, plus unconventional data integration methods uniquely suited for these deposits. This paper details the evolution of these novel ore characterisation techniques and their application to each phase of the operation: mining-concentrating-and pelletising. The improved ore characterisation techniques have contributed to successes at individual Cleveland-Cliffs managed operations including mineral recoveries exceeding 95 per cent and productivity increases exceeding ten per cent while consistently achieving customer product quality objectives.

Jan 1, 2002

Caving is the lowest cost underground mining method, provided that drawpoint spacing, drawpoint size and ore handling facilities are designed to suit the caved material and that the drawpoint horizon can be maintained for the draw life. In the near future several open pit mines that produce in excess of 50 000 tons per day will have to examine the feasibility of converting to low cost, large scale underground operations. Several other large scale, low grade underground operations will experience major changes in their mining environments as large dropdowns are implemented. These changes demand a more realistic approach to mine planning than has occurred in the past, where existing operations have been projected to increased depths with little consideration of the change in mining environment that will occur. As economics force the consideration of underground mining of large, competent orebodies by low cost methods, the role of cave mining will have to be defined. In the past caving has generally been considered for rock masses that cave and fragment readily. The ability to define cavability and fragmentation, the availability of large, robust LHDs, a better understanding of draw control requirements, improved drilling equipment for secondary blasting and reliable cost data have shown that competent orebodies with coarse fragmentation can be exploited by cave mining at a much lower cost than with drill and blast Methods.

Jan 1, 1995

THE following notes simply sum up the writer's experience, which extended over a very busy period of some three years, dealing with wolfram ores and concentrates. The three methods for the estimation of tungsten that are discussed below are well known, but these results of their trials and comparison under technical conditions may be interesting. Method I. The routine procedure for the assay of rich wolfram ores or concentrates was as follows: Take 1 gram of finely-ground sample; digest with HCl and HNOs for about 2 hours, evaporating down to near dryness. To the remaining 5 cc., say, of liquid, add water, warm or boil for 1 to 1.5 hour, filter through a small filter paper, and wash the beaker and the insoluble matter with hot dilute HCl. It is best to keep the bulk of the insoluble matter (WOs, Si02, etc.) in the beaker at this stage. Then plaee a weighed porcelain dish under the filter funnel and wash the beaker and the filter paper with successive small quantities of strong NHOH, finally bringing all the insoluble matter on to the filter paper, and collecting the ammoniacal filtrates in the porcelain dish (S). Then place the filter paper with the insoluble matter in a porcelain crucible, dry and burn off the paper, cool, and brush the contents of the crucible on to an agate mortar, grind it to flour, and brush this back to the original beaker without loss. In the absence of draughts this can be done safely. Re-treat this residue with' acid and ammonia as above, running the second ammoniacal filtrate into the previous porcelain dish, which in the meantime has been heating on a water-bath.Finally evaporate to dryness on the water-bath the combined ammoniaeal filtrate, and then heat gradually to a red heat over a Bunsen burner, cool, and weigh. Then the contents of the porcelain dish give the WOs (tungstie aeid) direcvly (5).The final filter paper and insoluble matter may be ignited in a porcelain crucible, thus giving the "insoluble matter." If the ore...

Jan 1, 1922

First of all, I should like to thank you for theopportunity to be with you tonight and tocongratulate the Kalgoorlie and Perth branchesof the Australasian Institute of Mining andMetallurgy in initiating this most importantConference.It could not have been better timed.Gold is riding a crest of the wave, leading theresurgence in the State's mining industry.The strong and stable economic policies whichhave been pursued both by the Burke LabourGovernment in this State and by the HawkeGovernment in Canberra, whilst they have ofcourse only been part of the reason for thestrong recovery in the mining industry - a l o tof it being due t o international factors - havecertainly assisted and ensured that the miningindustry in this state has been able to takefull advantage of the changed world situation.

Jan 1, 1984

This paper addresses the unique environ- mental programmes which prevail at Ranger and their importance in the future profitability, of Ranger Uranium Mines Pty Ltd. (RUM) Industrial relations, general safety, and occupational health have long been regarded as part and parcel of the concept to 'manage for profits'. More recently, the need for environmental protection has also become an important management consideration. This is particularly so at the Ranger Uranium Mine where environmental protection is very closely and continuously regulated. Since the commencement of operations at Ranger some three years ago the company has operated within these regulations and demonstrated clearly that yellowcake can be produced efficiently, economically and safely. The company also recognises that in order to ensure continuity of production, it will have to continue to operate within these strictly supervised Regulations.

Jan 1, 1984

By Brown P. L

A study has been made of the geochemistry of the Ronneburg mine district as input to the overall management strategy for the rehabilitation of the mine site. The study drew on the geological data and information store developed over the 40 years of mineral exploration and mining at Ronneburg, and on chemical data from the literature which described the chemical processes of weathering, oxidation, dissolution and precipitation of minerals. The geochemical processes were divided into three groups based on their rate of reaction. Fast processes were assumed to proceed to equilibrium and were modelled using equilibrium chemistry equations; slow processes were assumed to be proceeding at a quasi-steady state rate and were modelled using chemical rate equations; very slow processes were assumed to have no role in describing the geochemistry for rehabilitation purposes.

Jan 1, 1995

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

Pipe Jacking has been a recognised method of tunnelling in the U.K. since the early 1950's, although I understand that pipes were pushed blind by the soldiers in the first World War from trenches on the Allied side to, or adjacent to, trenches on the German side, thus allowing explosives to be used with a certain element of surprise! 'However, on its more conventional to the U.K. in the 1950's, Pipe Jacking made considerable inroads into the tunnelling market place as an alternative to timber supported headings. This success was, unfortunately, fairly short lived because, owing to its simple method of operation, contractors paid insufficient detail to the engineering (or surveying) aspects and as such the system soon had a bad reputation for unreliability and lack of accuracy. Due to these failings, the market was not exploited and, therefore, there was a lack of investment by contractors, pipe manufacturers and also by any client, or research organisation, which is client associated. The effect of this meant that the system stagnated for a number of years and was used generally only for short crossing work (i.e. railways, canals and motorways), and then only in good homogeneous ground. Albeit, a limited number of full scale sewage disposal contracts were carried out, but with the lack of knowledge and experience of the clients, contractors and suppliers, (particularly the pipe suppliers), no reasonable success, either physical or financial, was achieved on any such contract.

Jan 1, 1987

By Misra VN

The carbon-carbon dioxide reaction is the rate determining step in industrial processes such as the rotary kiln direct reduction process for iron ores. The use of brown coal as a reductant in the rotary kiln process has been shown to result in higher throughputs and lower kiln temperatures. No experimental data has been reported on the effect of coal type or the use of brown coal chars. Methods of carbon-carbon dioxide reacti- vity measurement are discussed. None of the methods have been related to direct reduction practice. No standard test has been developed to assess the reactivity of brown coal chars to carbon dioxide. For routine comparative work the gas analysis method of Okstad and Hoy appears to be the most suitable although some modification to the experimental conditions is required. For detailed kinetic studies direct weighing techniques are to be preferred. The factors affecting the reactivity of brown coal char to carbon dioxide are reviewed. Numerous factors such as the origin of the coal, pretreatment and ,physical and chemical differences have been found to affect the reactivity of brown coal chars but no data has been reported on the effect of coal type on reactivity to carbon dioxide.

Jan 1, 1980

By Brien RT, O&apos

The work reported in this paper extends,-bhsb on the "Heat Hardening of Artificial Magnetite ;Pellets"., which was described at the- International Symposium on Agglomeration ;-sponsored by the American Institute. of Mining, Metallurgical and Petroleum Engineers at Philadelphia; U.S.A. in April, 1961. Whereas- that work was of a.,more basic nature, -serving to illustrate the suitability of artificialòmagnetites with various.admixtures, to the application of heat hardened pellets, on: this occasion the aim-is to illustrate the procedures-which were used-to- establish the dimensions of commercialòrecuperativ strands for Australian raw materials,The nature of the pellet feed, i.e. relatively uniform :spheres of4 3/8 in. - 7/16. in. diameter, makes it possible to use small scale static pots for test work. By the use of a closed system and the measurement of suctions, gas f lows, and temperatures through beds, the speed and heat requirements of the various stages of heat hardening can be measured, so: that for a specified quality of product estimates can be made of the broad design characteristics of a moving grate system. In practice of course it is .usual to correlate the data from this type-of :experimental 'apparatus with . existing production units upon which good operating data, in the statistical sense, are available.

Jan 1, 1963

The history of the discovery. and successful development of the offshore Gippsland Basin oil and gas fields has been well docu- mented in contemporarary and more recent industry and profes- sional literature. The various articles, papers and books record fairly balanced views and comments as to the nature and results of the explora- tion effort, and factual data concerning the subsequent develop- ment of the fields and facilities concerned with petroleum production in the Bass Strait and Gippsland environment. Recommended reading for those interested in the scientific and technical aspects of the Gippsland Basin developments and the search for petroleum in the Bass and Alway Basins includes the available library contained in the publications of The Australasian Institute of Mining & Metallurgy The Commonwealth Mining Congres since 1960 The Australian Petroleum Exploration Association The Geological Society of Australia The American Association of Petroleum Geologists Various Commonwealth and Victorian Government instrumentalities Trade Journals

Jan 1, 1988

By C M. Côte, P Bolz, R Chrystal

The design of final landforms is an integral part of mine closure plans in Queensland and aims to ensure the rehabilitated land is safe, stable and non-polluting. Landform stability in this context is commonly assessed using Landscape Evolutions Models (LEM) which are physical models simulating sediment erosion and deposition around individual landforms over long timespans (up to thousands of years). The most used LEM for assessment of rehabilitated landforms in Queensland is SIBERIA (Willgoose, Bras and Rodriguez-Iturbe, 1991; Tucker and Hancock, 2010). SIBERIA models are complex, require very detailed input data and simulate erosion and deposition over time frames that extend decades beyond closure. They are not suitable to assess erosion risks during the operational phase of a mine and to support the development of erosion and sediment control plans. Other types of erosion models, such as the Revised Universal Soil Loss Equation (RUSLE, Wischmeier and Smith, 1978) or Water Erosion Prediction Project (WEPP, Nearing et al, 1989) calculate soil loss on a monthly or yearly basis and are much better suited to erosion management during the operational phase. They are simpler to implement and can support the design of control measures. For instance, designing a sediment basin requires quantification of sediment loads, which can be produced by these models. In Queensland, the legislation around sediment and erosion control for open cut mines is currently tightening. Soil erosion remains a major concern due to potential impacts on the receiving environment. It requires management during operation and for closure consideration alike and it is critical that erosion and sediment control plans are developed with the most appropriate tools. Globally, RUSLE is the most widely used soil loss model (Borrelli et al, 2021). This is because it is an empirical model with relatively simple input requirements: biophysical data such as soil properties, vegetation cover, topography and rainfall variability, which can be directly measured or derived from regional or national databases and/or spatial data sets that are available in most parts of the world. The second most used model is WEPP (Borrelli et al, 2021) but compared to RUSLE, there is a large drop in the frequency of its use. This is because WEPP is physically-based and has more complex data requirements. WEPP integrates hydrology, hydraulics, erosion mechanics and land cover to predict soil erosion and sediment transport on hill slope profiles and small watersheds (Stolpe, 2005). It requires some biophysical parameters in formats different from those of RUSLE, as well as detailed hydrologic and catchment data. Nevertheless, it has been used in landform design for mines across Australia to determine final landform stability (eg Howard and Roddy, 2012; Costin, 2020). In this study, we assess which tool would be the most appropriate to support development of erosion and sediment control plans from operation to closure. We use RUSLE and WEPP to predict soil loss from a mine site, compare the results from both models and outline the advantages of each method.

Aug 2, 2023

Computerisation of mine planning activities, specifically in the areas of geology, design and surveying, has been in progress for a number of years in underground metalliferous mines. The combined capabilities of hardware and software have only recently reached the levels necessary to fully support integrated mine planning computer systems in a graphical three dimensional environment. Despite the apparent capabilities of systems now on the market, many sites retain significant parts of their older paper based systems, and employ a mix of two or more software packages. This paper examines what underground metalliferous sites are doing in this area in Australia, and discusses the factors which are inhibiting full implementation of fully integrated computerised systems. Future directions for further developments in the field are also briefly discussed.

Jan 1, 1995

By Bailey S, Avraamides J, Jayasekera S

The anodic dissolution of iron from three different Western Australian reduced ilmenites was investigated using the carbon paste electrode technique. A characteristic current-potential diagram, called a cyclic voltammogram (CV), was obtained for each of the reduced ilmenites. The shape of the CV measured for all three reduced ilmenites was strongly time dependent. The effect of electrolyte composition and temperature on the CV of one reduced ilmenite was also investigated. The results suggest that the initial surface of iron in reduced ilmenite is slow to dissolve and that chloride ions and higher temperatures accelerate the dissolution of this initial surface layer. However, after removal of this layer, the dissolution rate was essentially independent of the electrolyte composition and the temperature.

Jan 1, 1996

By Hoskings AD

Bolting forms a prestressed elastic layer of rock which is capable of supporting loads at right angles to the bolted surface. Investigations on rock bolting made with a number of different models give rise to empirical and theoretical prin- ciples for the formation and action of the layer. In the models, flat and arched layers of many materials were used simulating rock conditions ranging from closely interlocked blocks to fragments of various shapes. Results of observations made in the underground works of the Snowy Mountains Scheme are related to the mode of action of bolted surface layers of rock. There is abundant experimental, theoretical and practical explanation for the well-demonstrated capability of bolting as a means of rock support.

Jan 1, 1971

By A Califice, E Pirard, M Benzaazoua, R Mermillod-Blondin

Image analysis is more and more considered as a powerful tool for quantitative analysis of ores and concentrates. Apart from being very much dependent upon the quality of the imaging principle and the adequacy of the imaging sensor, quantitative image analysis is also the result of a long chain of material, image and pixel sampling strategies. The most reliable way to demonstrate the accuracy and the precision of modal analysis obtained from images is probably to use a blended material with known proportions of pure minerals and confront the results obtained from different analytical tools. This operation has been performed on a series of mineral blends mimicking the tailings of a flotation operation in a plant operating on massive sulfide mineralisation. The intention was to be able to better predict acid mine drainage potential from direct mineralogical observations. Selected sulfide minerals: pyrite (Py), pyrrhotite (Po), chalcopyrite (Cp) and sphalerite (Sp) were mixed as variable amounts within gangue minerals (quartz, calcite, dolomite and siderite). Typical blends contained six to ten per cent (Py); one to three per cent (Po); 0.5 to one per cent (Cp, Sp); 15 to 40 per cent carbonates and 40 to 75 per cent quartz by mass. The 1000 gram blends were carefully sampled and prepared for X-ray diffraction, chemical analysis by ICP-AES and optical microscopy image analysis (OMIA). Results obtained for the different analytical techniques are compared and discussed revealing the limits and strength of each method in the accurate quantification of sulfide and gangue minerals.

Jan 1, 2008